HK1263105A1 - Method for recycling lithium-ion battery - Google Patents

Description

Method for recycling lithium ion battery

Technical Field

The invention relates to a method for recycling lithium ion batteries.

Background

Lithium-ion batteries (LIBs) have been widely used in various applications, such as consumer electronics, for the past decades due to their superior energy density, long life, and discharge capability. LIBs generally comprise an anode, an electrolyte and a cathode containing lithium in the form of a lithium-transition metal oxide.

In recent years, LIBs have begun to be used in a large number of automotive propulsion applications because these batteries provide reliable service for many years and are expected to be usable for about 10 years under normal driving conditions. These LIBs can then be used for utility energy storage until the end of their useful life.

Environmental issues caused by scrapping LIBs have attracted general public attention. If the usable material can be recovered from the used battery, the need to extract the raw material from the limited supply in the ground will be reduced. In addition, if the used LIB is recyclable, significant negative environmental effects from mining and processing of the ore (e.g., SO released from sulfide ore smelting processes) can be avoided_xFor example, a sulfide ore smelting process that produces copper, nickel, and cobalt).

Currently, methods of recycling waste LIBs can be divided into two major categories: leaching, and a combination roasting and leaching process. In general, the leaching process comprises the following steps: the battery is crushed or chopped, leached with acid, and the leached material is separated by precipitation, complexation and/or extraction. However, leaching involves complex leachate compositions and multiple separation steps that can produce large amounts of secondary waste.

The combined roasting and leaching process includes the following steps: crushing or chopping the battery, roasting, leaching with acid, separating the leached material, etc. However, this method has an additional disadvantage of higher energy consumption due to the use of the heat treatment process. In addition, the recovery rate of the electrode material is low because some components of the electrode material are burned to produce carbon dioxide and other harmful substances.

Various attempts have been made to solve the above problems and improve the performance of the recovery process. Chinese patent application publication No. CN 104577246A describes a method for recovering cathode and anode materials of a lithium ion battery. However, this method is time consuming and requires a lot of labor because the recycling method requires removal of the battery case.

Chinese patent application publication No. CN 103449395A discloses a method for recovering cathode materials from lithium iron phosphate batteries. However, this method requires a step of careful disassembly of the lithium iron phosphate battery to obtain an undamaged cathode plate and is limited to lithium iron phosphate batteries.

Chinese patent No. CN 101318712B discloses a method for recovering cobalt from LIB. However, the recyclates are limited to only LiCoO₂And is not suitable for recycling other cathode materials.

Chinese patent application publication No. CN 104409792A discloses a method for recovering cobalt from LIB. The method comprises the step of separating the materials of different densities based on a sink-float process, wherein the heavier fraction sinks to the bottom and the lighter fraction floats. This separation system, although conceptually very simple, has a number of disadvantages. When a solid material is wetted with water or an aqueous liquid, some of the light and heavy particles flocculate to form agglomerates. Thus, LiCoO is contained₂And carbon powder, a portion of the suspended solid particles settle and are removed in separating the heavier fraction, thereby complicating the separation process. In addition, this method is time consuming and not cost effective, since the lighter fraction, the heavier fraction and the suspended solid particles must be removed sequentially. Further, the recovered product is limited to LiCoO₂And is not suitable for recycling other cathode materials.

Thus, it can be seen that there is a continuing need to develop a LIB recovery process that has high recovery, high efficiency and low cost under mild conditions. In particular, there is a continuing need for a non-polluting method of recovering LIB to reduce air and water pollution generated in the recovery process.

Disclosure of Invention

The various aspects and embodiments disclosed herein meet the above-mentioned needs. In one aspect, provided herein is a method of recycling a lithium ion battery comprising the steps of:

a) discharging the lithium ion battery;

b) shredding the lithium ion battery into pieces to provide a mixture of a structural component, a first electrically conductive metal component coated with a cathode layer, and a second electrically conductive metal component coated with an anode layer;

c) immersing pieces of the chopped lithium ion battery into a polar solvent to form a heterogeneous mixture;

d) treating the heterogeneous mixture with mechanical agitation for a period of about 30 minutes to about 5 hours to dissolve the binder material in the cathode layer and the anode layer;

e) screening the treated heterogeneous mixture to separate the structural component, the first electrically conductive metal component and the second electrically conductive metal component from the finer electrode material comprising the cathode and anode materials to provide a suspension comprising a polar solvent and the finer electrode material; and

f) separating the finer electrode material from the polar solvent in the suspension;

wherein the polar solvent is water, an alcohol, a ketone, or a combination thereof;

wherein the cathode material is selected from the group consisting of LiCoO₂、LiNiO₂、LiNi_xMn_yO₂、LiNi_xCo_yO₂、Li_1+zNi_xMn_yCo_1-x-yO₂、LiNi_xCo_yAl_zO₂、LiV₂O₅、LiTiS₂、LiMoS₂、LiMnO₂、LiCrO₂、LiMn₂O₄、LiFeO₂、LiFePO₄And combinations thereof; wherein each x is independently 0.3 to 0.8; each y is independently 0.1 to 0.45; and each z is independently 0 to 0.2; and

wherein the binder material of each of the cathode layer and the anode layer is independently a water-based binder material or a mixture of a water-based binder material and an organic binder material.

In some embodiments, the lithium ion battery is shredded by a water jet cutter or a device with serrations or blades. In certain embodiments, the shredded pieces of lithium ion battery have an average length of about 0.5 inches to about 4.0 inches. In other embodiments, the pieces of shredded lithium ion batteries have an average length of about one-quarter inch or less.

In certain embodiments, each of the first and second conductive metal features is independently selected from the group consisting of: aluminum thin plate, copper thin plate, gold thin plate, silver thin plate, and platinum thin plate.

In some embodiments, the polar solvent is water. In other embodiments, the polar solvent is a mixture of water and an alcohol. In a further embodiment, the alcohol is selected from methanol, ethanol, isopropanol, n-propanol, tert-butanol or combinations thereof. In still further embodiments, the weight ratio of water to alcohol is from about 5:95 to about 95: 5.

In certain embodiments, the polar solvent is a mixture of water and a ketone. In a further embodiment, the ketone is selected from acetone, diethyl ketone, methyl ethyl ketone, methyl isobutyl ketone, and methyl propyl ketone, or a combination thereof. In still further embodiments, the weight ratio of water to ketone is from about 5:95 to about 95: 5.

In some embodiments, the polar solvent is a buffer solution comprising a salt selected from the group consisting of: lithium carbonate, lithium bicarbonate, lithium phosphate, sodium carbonate, sodium bicarbonate, sodium phosphate, potassium carbonate, potassium bicarbonate, potassium phosphate, ammonium carbonate, ammonium bicarbonate, ammonium phosphate, and combinations thereof. In certain embodiments, the buffer solution has a pH of about 6 to about 8.

In certain embodiments, the mechanical agitation step is performed by stirring, shaking, sonication, vortexing, or a combination thereof. In some embodiments, the mechanically agitating step is performed by a dispersion paddle mixer, an agitated mixer, a screw mixer, a conical screw mixer, a planetary agitated mixer, an air jet mixer, a high shear mixer, an ultrasonic bath, an ultrasonic probe, or a combination thereof.

In some embodiments, the heterogeneous mixture in step d) is heated at a temperature of about 35 ℃ to about 100 ℃. In some embodiments, the heterogeneous mixture in step d) is heated at a temperature of about 55 ℃ to about 75 ℃.

In some embodiments, the water-based binder material is selected from the group consisting of styrene-butadiene rubber, acrylated styrene-butadiene rubber, acrylonitrile-butadiene rubber, nitrile-butadiene rubber, acrylonitrile-styrene-butadiene copolymer, acrylic rubber, butyl rubber, fluoro-rubber, polytetrafluoroethylene, polyethylene, polypropylene, ethylene/propylene copolymer, polybutadiene, polyethylene oxide, chlorosulfonated polyethylene, polyvinylpyrrolidone, polyvinylpyridine, polyvinyl alcohol, polyvinyl acetate, polyepichlorohydrin, polyphosphazene, polyacrylonitrile, polystyrene, latex, acrylic resin, phenolic resin, epoxy resin, carboxymethyl cellulose, hydroxypropyl cellulose, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl cellulose, cyanoethyl sucrose, polyester, polyamide, polyether, polyimide, polycarboxylate, polyether, and mixtures thereof, Polycarboxylic acids, polyacrylic acids, polyacrylates, polymethacrylic acids, polymethacrylates, polyacrylamides, polyurethanes, fluorinated polymers, chlorinated polymers, alginates, and combinations thereof.

In certain embodiments, the organic binder material is selected from the group consisting of Polytetrafluoroethylene (PTFE), perfluoroalkoxy Polymer (PFA), polyvinylidene fluoride (PVDF), copolymers of Tetrafluoroethylene (TFE) and Hexafluoropropylene (HFP), fluorinated ethylene-propylene (FEP) copolymers, terpolymers of tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride, and combinations thereof.

In some embodiments, the finer electrode material further comprises a conductive agent.

In certain embodiments, the cathode material is LiNiO₂、LiNi_xMn_yO₂、LiNi_xCo_yO₂、Li_1+zNi_xMn_yCo_{1-x- y}O₂、LiNi_xCo_yAl_zO₂And combinations thereof; wherein each x is independently 0.5 to 0.8; each y is independently 0.1 to 0.4; and each z is independently 0 to 0.2.

In some embodiments, the anode material is a carbonaceous material.

In certain embodiments, the finer electrode material is screened through a screen having a mesh width of 2-4 mm. In certain embodiments, the finer electrode material is screened through a screen having a mesh width of 0.5-1.0 mm.

In some embodiments, the separation of the finer electrode material is performed by filtration, decantation, sedimentation, centrifugation, or a combination thereof.

In certain embodiments, the recovery of the finer electrode material is at least 90% or at least 95%. In some embodiments, the recovered finer electrode material has an impurity percentage of less than 2%, less than 1%, less than 0.5%, less than 0.1%, or less than 0.05%.

Drawings

FIG. 1 illustrates one embodiment of the method disclosed herein.

Figure 2 shows a schematic diagram of one embodiment of a high shear mixer.

Detailed Description

General definitions

The term "mechanical agitation" refers to the application of kinetic energy to a solid mixture in contact with a liquid to promote wetting of the solid mixture within the liquid. Some non-limiting examples of mechanical agitation include mixing, stirring, shaking, sonication, vortexing, and combinations thereof.

The term "water jet cutter" or "water jet cutter" refers to a tool capable of cutting various materials using an extremely high pressure water jet.

The term "heterogeneous mixture" refers to a mixture of two or more phases.

The term "electrode" refers to either the "cathode" or the "anode".

The term "cathode" is used interchangeably with cathode. Likewise, the term "negative electrode" is used interchangeably with anode.

The term "binder material" refers to a chemical or substance used to hold the electrode material and/or conductive agent in place and adhere it to the conductive metal component to form the electrode. In some embodiments, the electrode does not contain any conductive agent.

The term "water-based binder material" refers to a binder polymer that is water-soluble or dispersible in water. Some non-limiting examples of water-based binder materials include styrene-butadiene rubber, acrylated styrene-butadiene rubber, acrylic rubber, butyl rubber, fluororubber, polytetrafluoroethylene, polyethylene, polypropylene, ethylene/propylene copolymer, polybutadiene, polyethylene oxide, polyvinylpyrrolidone, polyepichlorohydrin, polyphosphazene, polyacrylonitrile, polystyrene, ethylene/propylene/diene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin, acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, and combinations thereof.

The term "organic binder material" refers to a binder that is soluble or dispersible in an organic solvent, especially N-methyl-2-pyrrolidone (NMP). Some non-limiting examples of organic binder materials include Polytetrafluoroethylene (PTFE), perfluoroalkoxy Polymer (PFA), polyvinylidene fluoride (PVDF), copolymers of Tetrafluoroethylene (TFE) and Hexafluoropropylene (HFP), fluorinated ethylene-propylene (FEP) copolymers, tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride terpolymers, and combinations thereof.

The term "conductive metal part" refers to a support for coating an electrode material and/or a conductive agent. Some non-limiting examples of conductive metal components include aluminum sheet, copper sheet, gold sheet, silver sheet, and platinum sheet.

The term "conductive agent" refers to a material that is chemically inert and has good electrical conductivity. Therefore, a conductive agent is often mixed with an electrode active material when forming an electrode to improve electrode conductivity. In some embodiments, the conductive agent is a carbonaceous material.

The term "carbonaceous material" refers to any material comprising at least 50 mole% carbon. Some non-limiting examples of carbonaceous materials include soft carbon, hard carbon, coke, graphite, carbon nanotubes, carbon fibers, graphite fibers, carbon nanofibers, graphite nanofibers, carbon black, activated carbon, and combinations thereof.

The term "sonicator" refers to a device that can apply ultrasonic energy to a sample to agitate particles. Any sonicator that can be used to disperse the heterogeneous mixture can be used herein. Some non-limiting examples of ultrasonic generators include ultrasonic bath and probe-type ultrasonic generators.

The term "ultrasonic bath" refers to a device that transfers ultrasonic energy into a sample liquid via the walls of the vessel of the ultrasonic bath.

The term "probe-type ultrasonic generator" refers to an ultrasonic probe immersed in a medium for direct ultrasonic treatment. The term "direct sonication" means that the ultrasonic waves are directly coupled to the treated liquid.

The term "dispersing paddle mixer" refers to a mixer comprising a vessel and a rotatable cutting member having at least one paddle. The paddle has at least one sharp edge. In some embodiments, the rotatable cutting member has a substantially vertical axis of rotation. The rotation speed may be expressed in revolutions per minute (rpm), which refers to the number of rotations the rotating body completes in one minute.

The term "agitator mixer" refers to a mixer comprising a vessel and a rotatable member having at least one arm. In some embodiments, the arm is rod-shaped, paddle-shaped, or plate-shaped.

The term "screw mixer" refers to a mixer comprising a vessel and a vertical mixing screw placed in the middle of the vessel. The container may be cylindrical, spherical or conical.

The term "conical screw mixer" refers to a mixer comprising a vessel tapering towards a bottom region, and at least one rotationally driven mixing screw moving parallel to and along the inner wall of the vessel.

The term "planetary mixer" refers to a device that can be used to mix or stir different materials to create a homogeneous mixture, consisting of single or double paddles with high speed dispersing paddles.

The term "air jet mixer" refers to a mixer comprising a vessel having a perforated wall and a plurality of nozzles from which a pressurized gas or liquid is emitted towards the material in the vessel.

The term "impact crusher" refers to a device comprising a housing, a rotor assembly, and a plurality of anvils disposed and configured about the rotor assembly for crushing material. The rotor assembly utilizes centrifugal force to throw the material out at high speed and, upon contact with the housing wall or anvil, the material breaks. This process is repeated until the crushed material is released from the outlet. Some non-limiting examples of impact crushers include horizontal impact crushers and vertical impact crushers.

The term "room temperature" refers to a temperature of about 18 ℃ to about 30 ℃, such as 18 ℃, 19 ℃, 20 ℃, 21 ℃, 22 ℃, 23 ℃, 24 ℃, 25 ℃, 26 ℃,27 ℃, 28 ℃, 29 ℃ or 30 ℃.

In the following description, all numbers disclosed herein are approximate values, regardless of whether the word "about" or "approximately" is used in connection therewith. These values may be in1%, 2%, 5%, or sometimes 10% to 20%. Whenever disclosed having a lower limit R^LAnd an upper limit R^UTo the extent that a range of values is recited, any value falling within the range is specifically disclosed. In particular, the following values within the ranges are specifically disclosed: r ═ R^L+k*(R^U-R^L) Where k is a variable with 1% increments in the range of 1% to 100%, i.e., k is 1%, 2%, 3%, 4%, 5%, … …, 50%, 51%, 52%, … …, 95%, 96%, 97%, 98%, 99% or 100%. In addition, any numerical range bounded by two R numerical values as defined above is also specifically disclosed.

Provided herein is a method of recycling a lithium ion battery comprising the steps of:

a) discharging the lithium ion battery;

b) shredding the lithium ion battery into pieces to provide a mixture of a structural component, a first electrically conductive metal component coated with a cathode layer, and a second electrically conductive metal component coated with an anode layer;

c) immersing pieces of the chopped lithium ion battery into a polar solvent to form a heterogeneous mixture;

d) treating the heterogeneous mixture with mechanical agitation for a period of about 30 minutes to about 5 hours to dissolve the binder material in the cathode layer and the anode layer;

e) screening the treated heterogeneous mixture to separate the structural component, the first electrically conductive metal component and the second electrically conductive metal component from the finer electrode material comprising the cathode and anode materials to provide a suspension comprising a polar solvent and the finer electrode material; and

f) separating the finer electrode material from the polar solvent in the suspension;

wherein the polar solvent is water, an alcohol, a ketone, or a combination thereof;

wherein the cathode material is selected from the group consisting of LiCoO₂、LiNiO₂、LiNi_xMn_yO₂、LiNi_xCo_yO₂、Li_1+zNi_xMn_yCo_1-x-yO₂、LiNi_xCo_yAl_zO₂、LiV₂O₅、LiTiS₂、LiMoS₂、LiMnO₂、LiCrO₂、LiMn₂O₄、LiFeO₂、LiFePO₄And combinations thereof; wherein each x is independently 0.3 to 0.8; each y is independently 0.1 to 0.45; and each z is independently 0 to 0.2; and

wherein the binder material of each of the cathode layer and the anode layer is independently a water-based binder material or a mixture of a water-based binder material and an organic binder material.

The present invention is intended to overcome the disadvantages of the conventional recovery method to provide a method for recovering a lithium ion battery with higher efficiency, low cost and easy operation. According to the present invention, it is possible to provide an efficient method for recycling a lithium ion battery in a simple manner.

FIG. 1 is a flow diagram of one embodiment of a process for recycling used lithium ion batteries. The invention simplifies the recovery method of the waste lithium ion battery and reduces the operation cost.

Prior to recycling, the lithium ion battery is discharged, as charge may still be stored in the battery. In some embodiments, the charge still stored in the battery is discharged by soaking the battery in an aqueous solution containing a conductive salt. In certain embodiments, the aqueous solution is neutral or basic. The discharging operation is advantageous in that safety can be ensured.

In some embodiments, the conductive salt is or comprises an alkali metal bicarbonate, such as sodium bicarbonate (NaHCO)₃) And potassium bicarbonate (KHCO)₃) (ii) a Alkali metal carbonates, e.g. sodium carbonate (Na)₂CO₃) And potassium carbonate (K)₂CO₃) (ii) a Alkaline earth metal carbonates, e.g. calcium carbonate (CaCO)₃) And magnesium carbonate (MgCO)₃) (ii) a Alkali metal hydroxides such as sodium hydroxide (NaOH) and potassium hydroxide (KOH); alkaline earth metal hydroxides, e.g. calcium hydroxide (Ca (OH)₂) Magnesium hydroxide (Mg (OH)₂) (ii) a Or alkali metal or alkaline earth metal halides, e.g. sodium chloride (NaCl) and calcium chloride (CaCl)₂) Or a combination thereof.

The resistance of the aqueous solution can be adjusted. The resistance of the solution is too low, leading to the risk of too rapid a discharge. On the other hand, too large a resistance will make the discharge time too long. In some embodiments, the solution resistance may be in the range of about 0.1 Ω to about 10k Ω by adjusting the concentration of the aqueous solution.

In certain embodiments, the total molar concentration of the conductive salt in the aqueous solution is from about 1mol/L to about 5mol/L, from about 1mol/L to about 4mol/L, from about 1mol/L to about 3mol/L, from about 2mol/L to about 5mol/L, from about 2mol/L to about 4mol/L, from about 2mol/L to about 3mol/L, or from about 4mol/L to about 5 mol/L. Within this range, the battery can be safely and controllably discharged. In other embodiments, the aqueous solution used for discharging does not contain any conductive salts.

In some embodiments, the cell may be perforated prior to immersion in the aqueous solution. The perforations may be formed by punching the casing and housing of the battery pack by impact piercing, saw cutting, or any other mechanical perforation method.

The discharged cells are then shredded into pieces to provide a mixture of the structural member, the cathode coated first electrically conductive metal member, and the anode coated second electrically conductive metal member.

In certain embodiments, the lithium ion battery is shredded by a water jet cutter or a device having serrations or blades. The operation of the cutter can be monitored by a computer so that the speed of the cutter can be automatically adjusted to ensure that the resulting battery fragments are of the desired size. In some embodiments, the lithium ion battery is disassembled to separate the cathode electrode and the anode electrode. In certain embodiments, the lithium ion battery is subjected to a heat treatment at a temperature ranging from about 100 ℃ to about 600 ℃ prior to shredding. In some embodiments, the lithium ion battery is not heat treated prior to shredding.

The cathode of the lithium secondary battery may have a structure in which a cathode layer is formed on the first conductive metal member. The anode of the lithium secondary battery may have a structure in which an anode layer is formed on the second conductive metal member. The conductive metal member serves as a current collector. Any metal having excellent conductivity that can be used as a current collector may be used herein.

In some embodiments, each of the first and second conductive metal parts is independently selected from the group consisting of: aluminum sheet, copper sheet, gold sheet, silver sheet, and platinum sheet. In some embodiments, the first conductive metal part is an aluminum sheet. In some embodiments, the second conductive metal part is a copper sheet.

Each cell is cut into smaller pieces by a cutter. In certain embodiments, the shredded pieces of lithium ion battery have an average length of about 0.5 inches to about 4.0 inches. In some embodiments, the pieces of shredded lithium ion batteries have an average length of about one-quarter inch or less.

The process disclosed herein does not involve a disassembly step. Thus, a large amount of work can be handled without dismantling.

One of the biggest challenges of the recovery process is the pollution caused by the use of many toxic and volatile organic solvents, resulting in even more toxic chemicals generated by the recovery process itself. Therefore, there is an urgent need to develop an environmentally friendly recovery process that can be performed in an aqueous medium or water. Furthermore, the use of an aqueous medium or water as a solvent offers many advantages, such as simplicity of operation.

The recovery process disclosed herein is non-toxic and environmentally friendly. The shredded pieces of lithium ion battery are immersed in a polar solvent to form a heterogeneous mixture. In some embodiments, polar solvent refers to a solution containing water and, in addition to water, possibly alcohols and the like. In certain embodiments, the amount of water is at least 1%, at least 2%, at least 3%, at least 4%, at least 5%, at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, or at least 95% relative to the total amount of water and solvent other than water. In some embodiments, the amount of water is at most 1%, at most 2%, at most 3%, at most 4%, at most 5%, at most 10%, at most 15%, at most 20%, at most 25%, at most 30%, at most 35%, at most 40%, at most 45%, at most 50%, at most 55%, at most 60%, at most 65%, at most 70%, at most 75%, at most 80%, at most 85%, at most 90%, or at most 95% relative to the total amount of water and solvent other than water. On the other hand, the upper limit is that the solvent consists only of water, i.e. the proportion of water is 100 vol.%.

In certain embodiments, the weight ratio of water to alcohol is about 99:1 to about 1:99, about 95:5 to about 5:95, about 10:1 to about 1:10, about 10:1 to about 1:1, about 8:1 to about 3:1, about 5:1 to about 3:1, about 4:1 to about 2:1, or about 3:1 to about 1: 3. In some embodiments, the weight ratio of water to alcohol is about 1:10, 1:9, 1:8, 1:7, 1:6, 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, or 10: 1.

Some non-limiting examples of alcohols include C₂-C₄Alcohols, methanol, ethanol, isopropanol, n-propanol, tert-butanol, and combinations thereof.

Some non-limiting examples of solvents other than water include lower aliphatic ketones such as acetone, dimethyl ketone, methyl ethyl ketone, and the like; other solvents such as ethyl acetate, isopropyl acetate, propyl acetate, and combinations thereof. In some embodiments, the component of the volatile solvent is methyl ethyl ketone, ethanol, ethyl acetate, or a combination thereof.

In some embodiments, the polar solvent is a mixture of water and a ketone. In a further embodiment, the ketone is selected from acetone, diethyl ketone, methyl ethyl ketone, methyl isobutyl ketone, and methyl propyl ketone, or a combination thereof. In still further embodiments, the weight ratio of water to ketone is from about 5:95 to about 95: 5. In certain embodiments, the weight ratio of water to ketone is about 1:10, 1:9, 1:8, 1:7, 1:6, 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, or 10: 1.

In certain embodiments, the polar solvent used to immerse the shredded pieces of the lithium-ion battery is water. Some non-limiting examples of water include tap water, bottled water, purified water, pure water, distilled water, deionized water, D₂O or a combination thereof. In some embodiments, the polar solvent is deionized water. In certain embodiments, the pH of the water is from about 6.5 to about 7.5. In some embodiments, the pH of the water is about 7.

In certain embodiments, the polar solvent is not an organic solvent or a mixture of water and an organic solvent. In some embodiments, the polar solvent is not an alcohol, acetone, or ether. In certain embodiments, the polar solvent is not N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide, tetrahydrofuran, formic acid, acetic acid, oxalic acid, or citric acid. In some embodiments, the polar solvent does not include an acid or a base.

In some embodiments, the polar solvent is a buffer solution comprising a salt selected from the group consisting of: lithium carbonate, lithium bicarbonate, lithium phosphate, sodium carbonate, sodium bicarbonate, sodium phosphate, potassium carbonate, potassium bicarbonate, potassium phosphate, ammonium carbonate, ammonium bicarbonate, ammonium phosphate, and combinations thereof. In certain embodiments, the buffer solution has a pH of about 6 to about 8. In some embodiments, the polar solvent is not a buffer solution.

In certain embodiments, the heterogeneous mixture is treated with mechanical agitation to aid in dissolution of the binder material. Any suitable method may be used to stir the heterogeneous mixture. Some non-limiting examples of suitable stirring methods may be achieved by mechanical stirring, magnetic stirring, shaking, sonication, vortexing, and combinations thereof.

In some embodiments, mechanical agitation is performed using an ultrasonic generator. Any sonicator that can apply ultrasonic energy to the sample to agitate the particles may be used herein. In some embodiments, the ultrasonic generator is a probe-type ultrasonic generator or an ultrasonic bath.

In certain embodiments, the ultrasonic generator is operated at a power density of about 10W/L to about 100W/L, about 40W/L to about 60W/L, about 20W/L to about 100W/L, about 30W/L to about 100W/L, about 40W/L to about 80W/L, about 40W/L to about 70W/L, about 40W/L to about 50W/L, or about 50W/L to about 60W/L.

One advantage of ultrasonic agitation is that it can reduce processing time. However, the problem caused by the poor penetration of the ultrasonic waves during the amplification is of great concern. The amplitude of the ultrasonic treatment should be increased when a large number of samples are treated, because the resistance of the samples to ultrasonic movement increases as the amount of samples increases. Therefore, a high amplitude (i.e., high strength) is required in order to obtain the desired mechanical vibration.

However, high amplitude ultrasonic treatment can cause rapid degradation of the ultrasonic transducer performance, resulting in poor conduction of the ultrasonic waves in the liquid medium. This problem becomes more severe when larger containers are used. On the other hand, the investment cost of ultrasonic equipment for large-scale operation is high and the energy cost is also higher than that of the mechanical agitation treatment.

In some embodiments, the heterogeneous mixture can be mechanically agitated. In certain embodiments, the heterogeneous mixture can be ultrasonically agitated. In some embodiments, mechanical agitation is performed using an agitator in the vessel or tank. Some non-limiting examples of mixers include dispersive paddle mixers, stirred mixers, planetary stirred mixers, screw mixers, conical screw mixers, and high shear mixers. In certain embodiments, the heterogeneous mixture is mechanically agitated using an air jet mixer. In some embodiments, the agitation device is not an ultrasonic generator, a dispersive paddle mixer, an agitated mixer, a planetary agitated mixer, a screw mixer, a conical screw mixer, a high shear mixer, or an air jet mixer.

The main advantage of using mechanical stirring is that it allows reliable scale-up from laboratory scale to pilot or larger scale. Other advantages of mechanical stirring include simple mechanical construction, simple maintenance and lower operating costs, especially reduced energy and cooling water costs, since the use of mechanical stirring will reduce the need for cooling water.

In some embodiments, the mechanical agitation may be performed for a period of time sufficient to peel the electrode material from the conductive metal member. In certain embodiments, the period of time is from about 1 hour to about 10 hours, from about 1 hour to about 8 hours, from about 1 hour to about 6 hours, from about 1 hour to about 4 hours, from about 1 hour to about 3 hours, from about 1 hour to about 2 hours, from about 2 hours to about 6 hours, from about 15 minutes to about 2 hours, or from about 30 minutes to about 2 hours. In some embodiments, the period of time is at least about 30 minutes, at least about 1 hour, at least about 2 hours, at least about 3 hours, at least about 4 hours, at least about 5 hours, at least about 6 hours, at least about 7 hours, at least about 8 hours, at least about 9 hours, or at least about 10 hours. In certain embodiments, the period of time is less than about 10 hours, less than about 9 hours, less than about 8 hours, less than about 7 hours, less than about 6 hours, less than about 5 hours, less than about 4 hours, less than about 3 hours, less than about 2 hours, or less than about 1 hour.

Generally, when mechanical stirring is performed by a paddle-less stirrer such as a stirring mixer, and the stirring time is less than 30 minutes, the dissolved amount of the binder material is relatively small and a large amount of the electrode material remains adhered to the conductive metal member. This will eventually reduce the amount of electrode material recovered. This is especially true when scaling up the recovery of LIB.

In some embodiments, the heterogeneous mixture is soaked in the polar solvent for a period of about 1 hour to about 5 hours prior to mechanical stirring. In other embodiments, the heterogeneous mixture is not soaked prior to mechanical agitation. It has been found that soaking alone in a polar solvent such as water is not sufficient to remove the electrode layer from the conductive metal part and soaking prior to mechanical agitation does not increase recovery.

Mechanical agitation is critical to removing the electrode layer from the conductive metal part. Shear forces generated by the mixer are required to remove the electrode layer from the conductive metal part. Collisions between battery fragments may also assist the removal of the electrode layer from the conductive metal part.

In some embodiments, the agitator is a dispersing paddle mixer. In certain embodiments, the dispersing paddle mixer comprises at least one sharp-edged paddle placed in the middle of the mixer. In some embodiments, the rotation speed of the dispersing paddles is about 1,000rpm to about 50,000rpm, about 5,000rpm to about 50,000rpm, about 10,000rpm to about 50,000rpm, or about 10,000rpm to about 30,000 rpm. In certain embodiments, the rotation speed of the dispersing paddles is about 1,000rpm, about 5,000rpm, about 10,000rpm, about 30,000rpm, or about 50,000 rpm. In some embodiments, the rotation speed of the dispersing paddles is less than about 50,000rpm, less than about 30,000rpm, less than about 10,000rpm, or less than about 5,000 rpm.

In certain embodiments, a strong transverse shear force is applied to the cathode/anode layer coated conductive metal part with the sharp edges of the paddles as the heterogeneous solution is stirred by the at least one paddle. The lateral shear forces cause fragments of the cathode/anode layer coated conductive metal parts to become smaller. Therefore, the thinner electrode material peeled off from the conductive metal member has a similar size to the conductive metal member. This makes it difficult to separate finer electrode materials from heterogeneous mixtures by sieving. A large number of structural parts and electrically conductive parts are attached to the finer electrode material.

In some embodiments, plastic beads are added to the heterogeneous mixture. Collisions between the beads and the electrode plate can enhance the peeling of electrode material from the electrode, thereby increasing recovery. Thus, a lower agitation speed may be used to reduce the amount of impurities collected from the finer electrode material while still maintaining recovery. After mechanically stirring the heterogeneous mixture, the plastic beads can be filtered so as not to contaminate the finer electrode material.

In some embodiments, the mass ratio of plastic beads to shredded battery is about 1:10 to about 1:100, about 1:20 to about 1:100, about 1:40 to about 1:100, about 1:60 to about 1:100, or about 1:80 to about 1: 100. In certain embodiments, the mass ratio of plastic beads to shredded battery is about 1:10, about 1:20, about 1:30, about 1:40, about 1:60, about 1:80, or about 1: 100. In some embodiments, the plastic beads are about 0.1mm to about 3mm, about 0.1mm to about 2mm, about 0.1mm to about 1mm, or about 0.1mm to about 0.5mm in diameter. In certain embodiments, the plastic beads are about 0.1mm, about 0.5mm, about 1mm, about 2mm, or about 3mm in diameter. In some embodiments, the plastic beads have a diameter of less than about 3mm, less than about 2mm, less than about 1mm, less than about 0.5mm, or less than about 0.1 mm.

In certain embodiments, the agitator is a stirred mixer. In some embodiments, the agitator mixer comprises at least one rod-shaped paddle placed in the center of the mixer. In certain embodiments, the rotational speed of the agitator mixer is about 50rpm to about 3,000rpm, about 50rpm to about 2,000rpm, about 50rpm to about 1,500rpm, about 50rpm to about 1,000rpm, about 50rpm to about 500rpm, or about 50rpm to about 200 rpm. In some embodiments, the rotational speed of the agitator mixer is about 50rpm, about 100rpm, about 200rpm, about 500rpm, about 1,000rpm, about 1,500rpm, about 2,000rpm, or about 3,000 rpm.

In some embodiments, the agitator is a planetary agitator mixer. In certain embodiments, the planetary agitator mixer comprises at least one single or double planetary paddle with at least one high speed dispersing paddle. In certain embodiments, the high speed dispersing paddles rotate at a speed of about 500rpm to about 2,500rpm, about 1,000rpm to about 3,000rpm, about 1,000rpm to about 2,500rpm, about 1,500rpm to about 2,500rpm, or about 2,000rpm to about 2,500 rpm. In some embodiments, the rotation speed of the planetary paddles is about 20rpm to about 150rpm, about 30rpm to about 100rpm, about 50rpm to about 300rpm, about 50rpm to about 200rpm, about 100rpm to about 300rpm, or about 200rpm to about 300 rpm.

In certain embodiments, the agitator is a screw mixer. In some embodiments, the screw is a left-handed screw or a right-handed screw. In some embodiments, the screw rotates clockwise or counterclockwise along its vertical axis. In some embodiments, the screw is rotated at a speed of about 100rpm to about 1,000rpm, about 100rpm to about 800rpm, about 100rpm to about 600rpm, about 100rpm to about 400rpm, or about 100rpm to about 200 rpm.

In some embodiments, the agitator is a conical screw mixer. In certain embodiments, the conical screw mixer comprises one screw. In other embodiments, the conical screw mixer comprises two screws. In certain embodiments, the conical screw mixer comprises at least one arm extending from the middle to the periphery of the mixer. The screw extends from the end of the arm and is inclined downwardly along the periphery of the mixer. The arm may surround the vessel of the conical screw mixer and the screw may spin. In some embodiments, the rotation speed of the arm is about 30rpm to about 300rpm, about 30rpm to about 250rpm, about 30rpm to about 200rpm, or about 50rpm to about 150 rpm. In certain embodiments, the screw is rotated at a speed of about 100rpm to about 1,000rpm, about 100rpm to about 800rpm, about 100rpm to about 600rpm, about 100rpm to about 400rpm, or about 100rpm to about 200 rpm.

In some embodiments, the agitator mixer is an air jet mixer. In certain embodiments, the air jets are emitted from holes in the mixer wall. In some embodiments, the pressure of the air jet is from about 0.01MPa to about 10MPa, from about 0.01MPa to about 1MPa, or from about 0.1MPa to about 1 MPa. In certain embodiments, a water jet is emitted from the bore.

In general, satisfactory recovery rates can be obtained when a dispersing paddle mixer is used. However, the sharp edges of the paddle will cut the material in the heterogeneous mixture into small pieces. Therefore, the collected electrode material is contaminated by impurities such as the conductive metal member.

Compared with the dispersing paddle mixer, a stirring mixer, a screw mixer, a conical screw are usedA rod mixer, planetary mixer or air jet mixer can obtain an electrode material with a low impurity content. However, surprisingly, a stirring system using a planetary or stirring mixer is not sufficient to contain, for example, LiNi_0.8Co_0.15Al_0.05O₂(NCA) and LiNi_0.6Mn_0.2Co_0.2O₂(NMC622) the electrode layer of high nickel cathode material is removed from the conductive metal feature. Prolonging the stirring time has no significant effect on improving efficiency. The combined effect of stirring and ultrasonic stirring is not improved. It is suspected that the strong alkalinity of the aqueous cathode slurry caused corrosion of the aluminum current collector resulting in strong adhesion between the cathode electrode layer and the aluminum current collector. In the above-mentioned mechanical stirrers, the shearing forces acting on the material in the heterogeneous mixture do not work sufficiently.

In some embodiments, the mixer is a high shear mixer. FIG. 2 is a diagram showing an embodiment of stirring a heterogeneous mixture using a high shear mixer. The high shear mixer comprises a mixing vessel 9 having an upper portion 9a and a lower conically tapered portion 9 b. In some embodiments, the upper portion 9a is cylindrical or conical. The mixing vessel 9 contains an inlet opening 8 in the upper part 9a for the introduction of the shredded lithium-ion battery chips and an outlet opening 10 in the lower part 9b for the discharge of the heterogeneous mixture produced in the vessel.

The high shear mixer shown in figure 2 comprises a screw 1 placed vertically in the centre of a mixing vessel 9. The screw 1 includes a rotary shaft 1a and a helical paddle 1b helically wound around the rotary shaft 1a of the screw 1. The rotary shaft 1a of the screw 1 is connected to a driving device. In certain embodiments, the drive means is an electric motor 11. In some embodiments, the helical paddle 1b rotates counterclockwise about the rotational axis 1a of the screw 1 from the axial end of the screw 1. Therefore, by rotating the screw 1 clockwise (in the direction indicated by the arrow R2 in fig. 2), the mixed material M around the screw 1 is pushed upward. When the material M is pushed upward, it is centrifugally pushed at the same time. Thus, the screw 1 generates a rising and centrifugal flow near the material M.

In some embodiments, the rotation speed of the screw 1 is about 500rpm to about 2,500rpm, about 500rpm to about 2,000rpm, about 500rpm to about 1,500rpm, about 1,000rpm to about 2,500rpm, or about 1,000rpm to about 2,000 rpm. In certain embodiments, the rotational speed of the screw 1 is about 500rpm, about 1,000rpm, about 1,500rpm, about 2,000rpm, or about 2,500 rpm.

The high shear mixer comprises a rotating member 2 for propelling the mixed material M in a downward and centripetal direction. In some embodiments, the high shear mixer comprises two or more rotating members 2. The rotary member 2 includes a cylindrical rotary shaft 7 of the rotary member 2 disposed coaxially with the rotary shaft 1a of the screw 1, a pair of rotary arms 6 extending horizontally and radially from the rotary shaft 7 of the rotary member 2, a support rod 4 extending vertically from the rotary arms 6, a paddle 3 fixed to the support rod 4, and a flow regulating plate 5 connected to the rotary member 2. The paddles 3 comprise an upper portion 3a bent forward with respect to the rotation direction of the rotating member 2 to push the material downward, a middle portion 3b fixed to the support rod 4, and a lower portion 3c inclined with respect to the radial direction to push the material centripetally. The paddles 3 extend up and down along the inner wall of the mixing vessel 9.

A flow regulating plate 5 is placed between the screw 1 and the stirring paddle 3 to impart centripetal motion to the mixed material M. In some embodiments, the flow adjusting plate 5 may be replaced with a structure having the support rod 4 and the stirring paddle 3 to increase the shear friction by collision of the mixed material M. In some embodiments, the flow regulating plate 5 may be omitted. The rotary part 2 is driven by an electric motor 12.

In some embodiments, the rotational speed of the rotating member 2 is about 50rpm to about 1,000rpm, about 50rpm to about 800rpm, about 50rpm to about 600rpm, about 50rpm to about 500rpm, or about 50rpm to about 300 rpm. In some embodiments, the rotational speed of the rotating member 2 is about 50rpm, about 100rpm, about 250rpm, about 300rpm, about 500rpm, or about 1,000 rpm.

In certain embodiments, the heterogeneous mixture is stirred in the high shear mixer for about 5 minutes to about 5 hours, about 5 minutes to about 3 hours, about 5 minutes to about 2 hours, about 5 minutes to about 1 hour, about 5 minutes to about 30 minutes, about 15 minutes to about 1 hour, about 30 minutes to about 5 hours, about 30 minutes to about 2 hours, about 30 minutes to about 1 hour, about 1 hour to about 5 hours, or about 2 hours to about 5 hours. In some embodiments, the heterogeneous mixture is stirred in the high shear mixer for less than about 2 hours, less than about 1 hour, less than about 30 minutes, less than about 20 minutes, or less than about 10 minutes. In certain embodiments, the heterogeneous mixture is stirred in the high shear mixer for at least about 10 minutes, at least about 20 minutes, at least about 30 minutes, at least about 1 hour, at least about 2 hours, at least about 3 hours, at least about 4 hours, or at least about 5 hours.

By rotating the screw 1 and the rotating member 2 in opposite directions, the material in the vessel around the screw 1 is pushed upwards and outwards, and the material around the rotating paddle 3 is pushed downwards and inwards. Thus, the centrifugally and centripetally pushed materials collide with each other in the area between the screw 1 and the rotating paddle 3 to form a high pressure area. In this region, the material undergoes intense shear friction. Since the heterogeneous mixture in the mixing container 9 can be efficiently circulated by convection while causing collision between the chips, the cathode electrode layer can be efficiently removed from the aluminum current collector for a short time. Furthermore, the conductive metal member and the structural member do not become small flakes or particles due to the peeling of the cathode layer from the conductive metal member caused by the shear friction, but remain discernable flakes. Therefore, a finer electrode material with a low impurity rate is obtained. Another advantage of the high shear mixer is that high recovery can be achieved in short processing times, even during large scale processing. Any temperature at which the heterogeneous mixture can be treated with mechanical agitation can be used herein. In some embodiments, the binder material is water-based and soluble in cold water. In certain embodiments, the treatment temperature is about 14 ℃, about 16 ℃, about 18 ℃, about 20 ℃, about 22 ℃, about 24 ℃, or about 26 ℃. In certain embodiments, mechanical agitation may be performed at room temperature. In some embodiments, the mechanical agitation can be performed at a temperature of less than 30 ℃, less than 25 ℃, less than 22 ℃, less than 20 ℃, less than 15 ℃, or less than 10 ℃. After processing the heterogeneous mixture, the cathode layer and the anode layer are separated from the conductive metal part and the electrode material particles are exfoliated from the electrode layer.

Increasing the temperature can increase the separation efficiency. In certain embodiments, the mechanical agitation can be performed at a heating temperature of about 35 ℃ to about 100 ℃, about 35 ℃ to about 80 ℃, about 35 ℃ to about 60 ℃, about 35 ℃ to about 50 ℃, about 55 ℃ to about 100 ℃, about 55 ℃ to about 75 ℃, or about 55 ℃ to about 65 ℃. After the heat treatment process, the cathode layer and the anode layer may be easily separated from the conductive metal part due to a difference in thermal expansion between the cathode layer and the anode layer and the conductive metal part. In certain embodiments, the mechanical stirring is performed at room temperature. In other embodiments, the mechanical agitation is performed at a temperature of less than 20 ℃, less than 25 ℃, less than 30 ℃, less than 35 ℃, less than 40 ℃, less than 50 ℃, less than 60 ℃, less than 70 ℃, less than 80 ℃, less than 90 ℃ or less than 100 ℃.

In some embodiments, the binder material is a mixture of a water-based binder material and an organic binder material. U.S. patent publication No. US20130034651 a1 discloses that organic binder materials such as PVDF can be used in a water-based slurry for making battery electrodes, provided that the slurry contains PVDF in combination with other water-based binder materials. It has been found that the methods disclosed herein are also applicable to the above-described binder systems and that the cathode layer and the anode layer can be separated from the electrically conductive metal part.

However, pure organic binders are difficult to dissolve because of their low solubility in water. In this case, the adhesive strength between the cathode layer and the anode layer and the conductive metal member is still strong, and therefore the cathode layer and the anode layer are less likely to be separated from the conductive metal member.

The positive electrode includes a cathode layer supported by a first conductive metal member. Typically, the first conductive metal part is an aluminum or other metal/conductive foil substrate. The cathode layer contains at least a cathode material and a binder material. The cathode layer may further include a conductive agent for enhancing electrical conductivity of the cathode layer. The positive electrode may include a quantity of binder material, such as a polymeric binder, and the binder material is used to bond the cathode material to the first conductive metal component.

The negative electrode includes an anode layer supported by a second conductive metal member. Typically, the second conductive metal part is a copper or other metal/conductive foil substrate. The anode layer contains at least an anode material and a binder material. The anode layer may further include a conductive agent for enhancing the electrical conductivity of the anode layer. The negative electrode may include a quantity of binder material for binding the anode material to the second conductive metal part.

In certain embodiments, the binder material in the cathode layer and the anode layer is the same or different. In some embodiments, the binder material is or comprises a water-based binder material, or a mixture of a water-based binder material and an organic binder material. In certain embodiments, the binder material is not an organic binder material or a mixture of a water-based binder material and an organic binder material.

In certain embodiments, the water-based binder material is selected from the group consisting of unsaturated polymers, conjugated diene polymers, styrene-butadiene rubber, acrylated styrene-butadiene rubber, acrylonitrile-butadiene rubber, nitrile-butadiene rubber, acrylonitrile-styrene-butadiene copolymers, rubber, acrylic rubber, butyl rubber, fluororubber, polytetrafluoroethylene, polyolefins, polyethylene, polypropylene, ethylene/propylene copolymers, polybutadiene, polyethylene oxide, chlorosulfonated polyethylene, polyvinylpyrrolidone, polyvinylpyridine, polyvinyl compounds, polyvinyl alcohol, polyvinyl acetate, polyepichlorohydrin, polyphosphazene, polyacrylonitrile, polystyrene, latex, acrylic resins, phenolic resins, epoxy resins, cellulose, carboxymethyl cellulose, hydroxypropyl cellulose, cellulose acetate butyrate, cellulose acetate propionate, polypropylene, polystyrene, and mixtures thereof, Cyanoethylcellulose, cyanoethylsucrose, polyesters, polyamides, polyethers, polyimides, polycarboxylates, polycarboxylic acids, polyacrylic acids, polyacrylates, polymethacrylic acids, polymethacrylates, polyacrylamides, polyurethanes, halogenated polymers, fluorinated polymers, chlorinated polymers, alginates, and combinations thereof.

Some non-limiting examples of polyvinyl compounds include polyvinyl compounds consisting of or containing N-vinylamide monomers such as N-vinylformamide and N-vinylacetamide. The poly-N-vinyl compounds are characterized by good wetting properties. Homopolymers, copolymers, and block copolymers may also be used herein. In some embodiments, the polyethylene compound is a random, block, or alternating interpolymer. In further embodiments, the polyvinyl compound is a diblock, triblock, or other multiblock interpolymer.

Some non-limiting examples of rubbers include natural rubber, isoprene rubber, butadiene rubber, chloroprene rubber, styrene-butadiene rubber, and nitrile-butadiene rubber. These rubbers contain unsaturated double bonds. In some embodiments, the rubber is a random, block, or alternating interpolymer. In further embodiments, the rubber is a diblock, triblock, or other multiblock interpolymer. Unsaturated polymers are generally characterized by good adhesion properties.

In certain embodiments, the alginate comprises a material selected from the group consisting of Na, Li, K, Ca, NH₄A cation of Mg, Al, or a combination thereof.

In some embodiments, the water-based binder material is a monomer containing carboxylic acid groups, sulfonic acid groups, or a combination thereof.

Some non-limiting examples of carboxylic acid group containing monomers include monocarboxylic acids, dicarboxylic acid anhydrides, and derivatives thereof. Some non-limiting examples of monocarboxylic acids include acrylic acid, methacrylic acid, crotonic acid, 2-ethacrylic acid, and isocrotonic acid. Some non-limiting examples of dicarboxylic acids include maleic acid, fumaric acid, itaconic acid, and citraconic acid. Some non-limiting examples of dicarboxylic acid anhydrides include maleic anhydride, acrylic anhydride, methyl maleic anhydride, and dimethyl maleic anhydride.

Some non-limiting examples of monomers having a sulfonic acid group include vinylsulfonic acid, methylvinylsulfonic acid, (meth) allylsulfonic acid, styrenesulfonic acid, (meth) acrylic acid-2-ethylsulfonate, 2-acrylamido-2-methylpropanesulfonic acid, 3-allyloxy-2-hydroxypropanesulfonic acid, and 2- (N-acryloyl) amino-2-methyl-1, 3-propane-disulfonic acid.

In some embodiments, the organic binder material is selected from the group consisting of Polytetrafluoroethylene (PTFE), perfluoroalkoxy Polymer (PFA), polyvinylidene fluoride (PVDF), copolymers of Tetrafluoroethylene (TFE) and Hexafluoropropylene (HFP), fluorinated ethylene-propylene (FEP) copolymers, tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride terpolymers, and combinations thereof. In other embodiments, the organic binder material is not Polytetrafluoroethylene (PTFE), perfluoroalkoxy Polymer (PFA), polyvinylidene fluoride (PVDF), a copolymer of Tetrafluoroethylene (TFE) and Hexafluoropropylene (HFP), a fluorinated ethylene-propylene (FEP) copolymer, or a tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride terpolymer.

In certain embodiments, the mass ratio of the water-based binder material to the organic binder material in the electrode layer is from about 10:1 to about 1:10, from about 10:1 to about 1:1, from about 10:1 to about 2:1, from about 10:1 to about 4:1, from about 10:1 to about 6:1, or from about 10:1 to about 8: 1. In some embodiments, the mass ratio of the water-based binder material to the organic binder material in the electrode layer is about 10:1, about 8:1, about 6:1, about 4:1, about 2:1, or about 1: 1.

After dissolution of the binder material, the treated heterogeneous mixture is screened to separate the structural component, the first conductive metal component and the second conductive metal component from the finer electrode material comprising the cathode and anode materials to provide a suspension comprising a polar solvent and the finer electrode material.

In certain embodiments, the finer electrode material is screened through a screen having a grid width between 2mm and 4 mm. In some embodiments, the finer electrode material is screened through a screen having a grid width between 0.5mm and 1.0 mm.

In some embodiments, the finer electrode material further comprises a conductive agent. In this case, the above suspension contains a polar solvent and a finer electrode material containing a cathode material, an anode material and a conductive agent.

In certain embodiments, the cathode material is a lithium metal oxide. In a further embodiment, the lithium metal oxide is selected from the group consisting of LiNiO₂、Li_1+zNi_xMn_yO₂、Li_1+zNi_xMn_yCo_1-x-yO₂、Li_1+zNi_xCo_yAl_zO₂、LiV₂O₅、LiTiS₂、LiMoS₂、LiMnO₂、LiCoO₂(LCO)、LiCrO₂、LiMn₂O₄(LMO)、LiFePO₄(LFP) and combinations thereof, wherein each x is independently 0.3 to 0.8; each y is independently 0.1 to 0.45; and each z is independently 0 to 0.2.

In some embodiments, the lithium metal oxide can include NMC (Li) with various Ni: Mn: Co ratios, e.g., 1:1:1, 5:3:2, 4:4:2, 8:1:1_1+zNi_xMn_yCo_1-x-yO₂). In certain embodiments, the lithium metal oxide is LiNi_0.33Mn_0.33Co_0.33O₂(NMC333)、LiNi_0.5Mn_0.3Co_0.2O₂(NMC532)、LiNi_0.6Mn_0.2Co_0.2O₂(NMC622)、LiNi_0.8Mn_0.1Co_0.1O₂(NMC811)、LiNi_0.8Co_0.15Al_0.05O₂(NCA) and combinations thereof. In other embodiments, the lithium metal oxide is not LiNiO₂、Li_1+zNi_xMn_yO₂、Li_1+zNi_xMn_yCo_1-x-yO₂、Li_1+zNi_xCo_yAl_zO₂、LiV₂O₅、LiTiS₂、LiMoS₂、LiMnO₂、LiCoO₂、LiCrO₂、LiMn₂O₄Or LiFePO₄WhereinEach x is independently 0.3 to 0.8; each y is independently 0.1 to 0.45; and each z is independently 0 to 0.2. In certain embodiments, the lithium metal oxide is not LiNi_0.33Mn_0.33Co_0.33O₂(NMC333)、LiNi_0.5Mn_0.3Co_0.2O₂(NMC532)、LiNi_0.6Mn_0.2Co_0.2O₂(NMC622)、LiNi_0.8Mn_0.1Co_0.1O₂(NMC811) or LiNi_0.8Co_0.15Al_0.05O₂(NCA)。

In certain embodiments, the anode material is selected from the group consisting of natural graphite particles, synthetic graphite particles, Sn particles, Li₄Ti₅O₁₂Particles, Si-C composite particles, and combinations thereof.

In some embodiments, the conductive agent is a carbonaceous material. In certain embodiments, the carbonaceous material is soft carbon, hard carbon, coke, graphite, carbon nanotubes, carbon fibers, graphite fibers, carbon nanofibers, graphite nanofibers, carbon black, activated carbon, or combinations thereof.

After the screening step, the finer electrode material in the suspension is separated from the polar solvent. The cathode material and the anode material can be recovered simultaneously, thereby simplifying the recovery process. The separated electrode material can be easily collected and the recovery rate of the electrode material is high.

Separation of the finer electrode material can be accomplished by a variety of methods known in the art, including (but not limited to) filtration, decantation, sedimentation, and centrifugation.

In some embodiments, the finer electrode material in the suspension may be collected from the polar solvent by filtration. Suitable filtration methods include gravity filtration, pressure filtration or vacuum filtration.

When the number of cell fragments in the heterogeneous mixture is large, and the mechanical stirring time is too long (e.g., about 5 hours), it is observed that the exfoliated water-based binder material may form colloids, which tend to form flocs when the number of cell fragments in the heterogeneous mixture is large. In such cases, the holes of the screen tend to become rapidly plugged with glue, causing the screen to become partially or completely unusable. Surprisingly, it was found that the formation of colloids can be suppressed by using a buffer solution, and thus the time required for the relevant process can be shortened and the screening efficiency can be improved.

In some embodiments, the recovery of the finer electrode material is at least 80%, at least 85%, at least 90%, or at least 95%. In certain embodiments, the recovery of the finer electrode material is about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, or about 99%.

In some embodiments, the recovered finer electrode material has an impurity percentage of less than 10%, less than 8%, less than 6%, less than 4%, less than 2%, less than 1%, less than 0.5%, less than 0.1%, or less than 0.05%.

Typically, when the electrode coating is dried and cured, it is then compressed to a calender to increase the density of the electrode coating. The cathode electrode layer has a higher compression density than the anode electrode layer, thereby increasing the energy density. Therefore, it is more difficult to separate the cathode electrode layer from the cathode current collector.

The recovery process disclosed herein involves water-based recovery techniques that do not require high temperature or strong acid environments, which are rendered exceptionally environmentally friendly by aqueous processes. Furthermore, the methods disclosed herein are simple and easy to scale up and are low in operating costs.

The following examples are intended to describe embodiments of the invention by way of illustration, but are not intended to limit the invention to the particular embodiments enumerated. Unless indicated to the contrary, all parts and percentages are by weight. All numerical values are approximate. When referring to numerical ranges, it should be understood that embodiments outside of the stated ranges may still be within the scope of the invention. The specific details described in each example should not be construed as essential features of the invention.

Examples

The impurity rate of the separated electrode material was measured by an inductively coupled plasma mass spectrometer (from PerkinElmer, inc.).

Example 1

Assembly of full lithium ion soft package battery

Preparation of the Positive electrode

For the preparation of the positive electrode, 94 wt.% of cathode material (NMC333) (LNMC TLM 310, obtained from Xinxiang Tianli Energy co.ltd., China), 3 wt.% of carbon black as a conductive agent (SuperP; obtained from pemphigh gmbh, Bodio, Switzerland) and 3 wt.% of polyacrylonitrile as a binder (LA 132, Chengdu Indigo Power Sources co.ltd., China), were dispersed in deionized water to form a slurry with a solid content of 50 wt.%. The slurry was then uniformly coated on an aluminum foil as a current collector using a blade coater (obtained from Shenzhen KejingStar Technology Ltd., China; model MSK-AFA-III) and dried at 50 ℃ for 12 hours to obtain a cathode aluminum sheet.

Preparation of the negative electrode

For the preparation of the negative electrode, 90 wt.% hard carbon (HC; purity 99.5%, obtained from ruiflute Technology ltd, Shenzhen, Guangdong, China) was dispersed in deionized water with 5 wt.% polyacrylonitrile as a binder and 5 wt.% carbon black as a conductive agent to form another slurry with a 50 wt.% solids content. The slurry was then uniformly coated on a copper foil as a current collector using a blade coater and dried at 50 ℃ for 12 hours to obtain an anode copper sheet.

Assembly of pouch cells

After drying, the obtained cathode sheet and anode sheet were cut into square sheets to prepare a cathode sheet and an anode sheet having a size of 8cm × 12cm, respectively. The cathode sheets and the anode sheets were stacked in an alternating manner with a 25 μm thick porous polyethylene separator (Celgard, LLC, US) between the cathode and anode sheets to prepare a pouch cell. The electrolyte was a solution of LiPF6(1M) in a mixture of Ethylene Carbonate (EC), Ethyl Methyl Carbonate (EMC) and dimethyl carbonate (DMC) in a volume ratio of 1:1: 1. The cell was assembled in a high purity argon atmosphere with humidity and oxygen content <1 ppm. After the electrolyte filling, the pouch cell was vacuum sealed and then mechanically pressed using a punching die having a standard shape.

The assembled pouch cells were then subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.2V to simulate a realistic usage pattern. The actual battery capacity was about 5 Ah. After 800 cycles, the rated capacity drops below 80% of its original rated capacity.

Battery recycling

The used lithium ion battery (0.5kg) was completely discharged by soaking in 6% NaCl solution for 12 hours. After discharge, the lithium ion battery was chopped into chips by a water jet cutter (YCWJ-3038-L2015-1D, from YC industrial co, Ltd, Jiangsu, China) in Jiangsu, China. Shredded lithium ion battery chips having an average length of about 0.5 inches to about 1.0 inches were immersed in deionized water (5L) at 20 ℃ to form a heterogeneous mixture. The mixture was mechanically stirred at 20 ℃ for 1 hour with a dispersing blade mixer (10L, from Chienemei Industry co. The rotation speed of the mixing paddle was 15,000 rpm. The cathode material is separated from the aluminum foil while the anode material is peeled off the copper foil. After stirring, the structural member, copper foil and aluminum foil were removed through a screen having a 4mm mesh width, thereby obtaining a suspension comprising water and an electrode material. After removing the structural member, the copper foil and the aluminum foil, the suspension was filtered to obtain an electrode material. The recovered electrode material was placed in an oven at 80 ℃ and dried at atmospheric pressure for 5 hours to give a final yield of 90%. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 2

Assembly of full lithium ion soft package battery

Soft pack lithium ion cells were prepared according to example 1. The assembled pouch cells were subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.2V to simulate real-world usage patterns. The actual battery capacity was about 5 Ah. After 800 cycles, the rated capacity drops below 80% of its original rated capacity.

The used lithium ion battery (about 20kg) was completely discharged by soaking in 6% NaCl solution for 12 hours. After discharge, the lithium ion battery was chopped into chips by a water jet cutter (YCWJ-3038-L2015-1D, from YC industrial ltd, Jiangsu, China). Pieces of chopped lithium ion batteries having an average length of about 0.5 inches to about 1.0 inch were immersed in deionized water (25L) at 20 ℃ to form a heterogeneous mixture. The mixture was stirred by an Ultrasonic probe (NP 2500; obtained from Guingzhou Newpwower Ultrasonic electronics Co., Ltd., China) at an input power of 200W at 20 ℃ for 2 hours. The cathode material is separated from the aluminum foil while the anode material is peeled off the copper foil. After the ultrasonic treatment, the structural member, the copper foil and the aluminum foil were removed through a screen having a 4mm mesh width, thereby obtaining a suspension containing water and an electrode material. After removing the structural member, the copper foil and the aluminum foil, the suspension was filtered to obtain an electrode material. The recovered electrode material was placed in an oven at 80 ℃ and dried at atmospheric pressure for 5 hours, resulting in a final yield of 63%. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 3

Assembly of full lithium ion soft package battery

Soft pack lithium ion cells were prepared according to example 1. The assembled pouch cells were subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.2V to simulate a realistic usage pattern. The actual battery capacity was about 5 Ah. After 800 cycles, the rated capacity drops below 80% of its original rated capacity.

Battery recycling

The used lithium ion battery (about 20kg) was completely discharged by soaking in 6% NaCl solution for 12 hours. After discharge, the lithium ion battery was chopped into chips by a water jet cutter (YCWJ-3038-L2015-1D, from YC industrial ltd, Jiangsu, China). Pieces of chopped lithium ion batteries having an average length of about 0.5 inches to about 1.0 inch were immersed in deionized water (25L) at 20 ℃ to form a heterogeneous mixture. The mixture was mechanically stirred at 20 ℃ for 2 hours with a dispersing blade mixer (30L, from Chienemei Industry co. The cathode material is separated from the aluminum foil while the anode material is peeled off the copper foil. After stirring, the structural member, copper foil and aluminum foil were removed through a screen having a 4mm mesh width to obtain a suspension containing water and an electrode material. After removing the structural member, the copper foil and the aluminum foil, the suspension was filtered to obtain an electrode material. The recovered electrode material was placed in an oven at 80 ℃ and dried at atmospheric pressure for 5 hours, resulting in a final yield of 93%. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 4

Assembly of full lithium ion soft package battery

Preparation of the Positive electrode

For the preparation of the positive electrode, 92 wt.% of cathode material (LMO) (LiMn) was used₂O₄Obtained from HuaGuan constant source lite ltd, national celand island (hua guan hongyuan liech co. ltd., Qingdao, China), 3 wt.% of carbon black as a conductive agent (SuperP; available from bodie tmigh co, switzerland) and as a binder 1 wt.% of carboxymethyl cellulose (CMC, BSH-12, DKS corporation of Japan (DKS co. ltd., Japan)), 3 wt.% of styrene-butadiene rubber (SBR) (AL-2001, Japan a)&L company (NIPPON A)&L inc., Japan)) and 2 wt.% of polyvinylidene fluoride (PVDF;5130, obtained from Solvay s.a., Belgium, and spelt, respectively, in N-methyl-2-pyrrolidone (NMP; 99% purity, Sigma-Aldrich, USA to form a slurry with 50 wt.% solids content. The slurry was then uniformly coated on an aluminum foil as a current collector using a blade coater and dried at 50 ℃ for 12 hours to obtain a cathode aluminum sheet.

Preparation of the negative electrode

For the preparation of the negative electrode, 90 wt.% of hard carbon (HC; purity 99.5%, obtained from china, guangdong shenzhen ruford technologies ltd.) and 1.5 wt.% of CMC (BSH-12, DKS corporation of japan) and 3.5 wt.% of SBR (AL-2001, japan a & L company) as binders and 5 wt.% of carbon black as a conductive agent were dispersed in deionized water to form another slurry having a solid content of 50 wt.%. The slurry was then uniformly coated on a copper foil as a current collector using a blade coater and dried at 50 ℃ for 12 hours to obtain an anode copper sheet.

Assembly of pouch cells

After drying, the obtained cathode sheet and anode sheet were cut into square sheets to prepare a cathode sheet and an anode sheet having a size of 8cm × 12cm, respectively. Stacking cathode sheets and anode sheets in an alternating manner, with the cathode sheets and the anode sheets therebetweenPouch cells were prepared at 25 μm thick porous polyethylene separator intervals (seikadard LLC, usa). The electrolyte is LiPF in a mixture of Ethylene Carbonate (EC), Ethyl Methyl Carbonate (EMC) and dimethyl carbonate (DMC) in a volume ratio of 1:1:1₆(1M) of a solution. The battery has humidity and oxygen content<1ppm of high purity argon atmosphere. After the electrolyte filling, the pouch cell was vacuum sealed and then mechanically pressed using a punching die having a standard shape.

The assembled pouch cells were then subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.3V to simulate a realistic usage pattern. The actual battery capacity was about 4.2 Ah. After 1,000 cycles, the rated capacity drops below 80% of its original rated capacity.

Battery recycling

The used lithium ion battery (0.5kg) was completely discharged by soaking in a 4% NaCl solution for 12 hours. After discharge, the lithium ion battery was chopped into chips by a battery cutter (KaidiMachinery, Zhengzhou, China). Pieces of chopped lithium ion batteries having an average length of about 1 inch to about 1.5 inches were immersed in deionized water (10L) at room temperature to form a heterogeneous mixture. The mixture was ultrasonically stirred in an ultrasonic bath (G-100ST, from Shenzhen Genging Cleaning Equipment Co. Limited.) at room temperature for 0.5 hours. The cathode material is separated from the aluminum foil while the anode material is peeled off the copper foil. After stirring, the structural member, copper foil and aluminum foil were removed through a screen having a mesh width of 2mm to obtain a suspension containing water and an electrode material. After removing the structural member, the copper foil and the aluminum foil, the suspension was filtered to obtain an electrode material. The recovered electrode material was placed in an oven at 80 ℃ and dried at atmospheric pressure for 5 hours, resulting in a final yield of 93%. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 5

Assembly of full lithium ion soft package battery

Preparation of the Positive electrode

For the preparation of the positive electrode, 94 wt.% of the cathode material LiCoO was used₂(LCO) (available from Xiamen Tungsten co. ltd., China), 3 wt.% carbon black (SuperP; available from bodi tmigh, switzerland) as a conductive agent, and 3 wt.% polyacrylic acid (PAA, #181285, available from sigma-aldrich, usa) as a binder were dispersed in deionized water to form a slurry having a solids content of 50 wt.%. The slurry was then uniformly coated on an aluminum foil as a current collector using a blade coater and dried at 50 ℃ for 12 hours to obtain a cathode aluminum sheet.

Preparation of the negative electrode

For the preparation of the negative electrode, 90 wt.% of hard carbon (HC; purity 99.5%, obtained from china, guangdong shenzhen ruford technologies ltd.) and 1.5 wt.% of CMC (BSH-12, DKS corporation of japan) and 3.5 wt.% of SBR (AL-2001, japan a & L company) as binders and 5 wt.% of carbon black as a conductive agent were dispersed in deionized water to form another slurry having a solid content of 50 wt.%. The slurry was then uniformly coated on a copper foil as a current collector using a blade coater and dried at 50 ℃ for 12 hours to obtain an anode copper sheet.

Assembly of pouch cells

After drying, the obtained cathode sheet and anode sheet were cut into square sheets to prepare a cathode sheet and an anode sheet having a size of 8cm × 12cm, respectively. The cathode sheets and the anode sheets were stacked in an alternating manner with a 25 μm thick porous polyethylene separator (seikadard LLC, usa) therebetween to prepare a pouch cell. The electrolyte is LiPF in a mixture of Ethylene Carbonate (EC), Ethyl Methyl Carbonate (EMC) and dimethyl carbonate (DMC) in a volume ratio of 1:1:1₆(1M) of a solution. Battery holderHas humidity and oxygen content<1ppm of high purity argon atmosphere. After the electrolyte filling, the pouch cell was vacuum sealed and then mechanically pressed using a punching die having a standard shape.

The assembled pouch cells were then subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.3V to simulate a realistic usage pattern. The actual battery capacity was about 5.2 Ah. After 650 cycles, the rated capacity drops below 80% of its original rated capacity.

Battery recycling

The used lithium ion battery (0.5kg) was completely discharged by soaking in 6% NaCl solution for 12 hours. After discharge, the lithium ion battery was chopped into chips by a water jet cutter (YCWJ-3038-L2015-1D, from YC industrial ltd, Jiangsu, China). Pieces of chopped lithium ion batteries having an average length of about 0.5 inches to about 1.0 inch were immersed in deionized water (5L) at 20 ℃ to form a heterogeneous mixture. The mixture was mechanically stirred at 20 ℃ for 2 hours with a dispersing blade mixer (10L, from Chienemei Industry co. The cathode material is separated from the aluminum foil while the anode material is peeled off the copper foil. After stirring, the structural member, copper foil and aluminum foil were removed through a screen having a 4mm mesh width, thereby obtaining a suspension comprising water and an electrode material. After removing the structural member, the copper foil and the aluminum foil, the suspension was filtered to obtain an electrode material. The recovered electrode material was placed in an oven at 70 ℃ and dried at atmospheric pressure for 5 hours to give a final yield of 90%. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 6

Assembly of full lithium ion soft package battery

Soft pack lithium ion cells were prepared according to example 5. The assembled pouch cells were subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.2V to simulate a realistic usage pattern. The actual battery capacity was about 5 Ah. After 700 cycles, the rated capacity drops below 80% of its original rated capacity.

Battery recycling

The used lithium ion battery (0.5kg) was completely discharged by soaking in 6% NaCl solution for 12 hours. After discharge, the lithium ion battery was chopped into chips by a water jet cutter (YCWJ-3038-L2015-1D, from YC industrial ltd, Jiangsu, China). Pieces of chopped lithium ion batteries having an average length of about 0.5 inch to about 1.0 inch were immersed into 0.05M phosphate buffer solution (5L) at a pH of about 6.8 at 20 ℃ to form a heterogeneous mixture. Phosphate buffer solution was prepared by dissolving 39g of sodium dihydrogen phosphate dihydrate (NaH)₂PO₄·2H₂O, available from sigma-aldrich, usa) was dissolved in deionized water (5L). The resulting mixture was mechanically stirred at 20 ℃ for 2 hours with a dispersing blade mixer (10L, from chienemei industry co. The cathode material was separated from the aluminum foil while the anode material was falling off the copper foil. After stirring, the structural member, copper foil and aluminum foil were removed through a screen having a 4mm mesh width to obtain a suspension containing the buffer solution and the electrode material. After removing the structural member, the copper foil and the aluminum foil, the suspension was filtered to obtain an electrode material. The recovered electrode material was placed in an oven at 80 ℃ and dried at atmospheric pressure for 5 hours to give a final yield of 95%. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 7

Assembly of full lithium ion soft package battery

Preparation of the Positive electrode

For the preparation of the positive electrode, 91 wt.% of cathode material LiFePO₄(LFP) (from China building)Available from wolfram door company, inc), 5 wt.% of carbon black (SuperP; available from bosdi tex high limited, switzerland) and 4 wt.% sodium alginate as a binder (SA, #180947, available from sigma-aldrich, usa) were dispersed in deionized water to form a slurry with a solids content of 50 wt.%. The slurry was then uniformly coated on an aluminum foil as a current collector using a blade coater and dried at 50 ℃ for 12 hours to obtain a cathode aluminum sheet.

Preparation of the negative electrode

For the preparation of the negative electrode, 90 wt.% of hard carbon (HC; purity 99.5%, obtained from kunto, china, professal, rafford technologies ltd.) was dispersed in deionized water with 1.5 wt.% CMC (BSH-12, DKS corporation japan) as a binder, 3.5 wt.% SBR (AL-2001, japan a & L company) and 5 wt.% carbon black as a conductive agent to form another slurry having a solid content of 50 wt.%. The slurry was then uniformly coated on a copper foil as a current collector using a blade coater and dried at 50 ℃ for 12 hours to obtain an anode copper sheet.

Assembly of pouch cells

After drying, the obtained cathode sheet and anode sheet were prepared into a cathode sheet and an anode sheet having a size of 8cm × 12cm, respectively, by cutting into square sheets. The cathode sheets and the anode sheets were stacked in an alternating manner with a 25 μm thick porous polyethylene separator (seikadard LLC, usa) therebetween to prepare a pouch cell. The electrolyte is LiPF in a mixture of Ethylene Carbonate (EC), Ethyl Methyl Carbonate (EMC) and dimethyl carbonate (DMC) in a volume ratio of 1:1:1₆(1M) of a solution. The battery has humidity and oxygen content<1ppm of high purity argon atmosphere. After the electrolyte filling, the pouch cell was vacuum sealed and then mechanically pressed using a punching die having a standard shape.

The assembled pouch cells were then subjected to repeated charge and discharge cycles at a constant current rate of 1C between 2.5V and 3.6V to simulate a realistic usage pattern. The actual battery capacity was about 4 Ah. After 500 cycles, the rated capacity drops below 80% of its original rated capacity.

Battery recycling

The used lithium ion battery (0.5kg) was completely discharged by soaking in 6% NaCl solution for 12 hours. After discharge, the lithium ion battery was chopped into chips by a water jet cutter (YCWJ-3038-L2015-1D, from YC industrial ltd, Jiangsu, China). Pieces of chopped lithium ion batteries having an average length of about 0.5 inches to about 1.0 inch were immersed into a mixture of deionized water (6.5L) and ethanol (1.5L) at 20 ℃ to form a heterogeneous mixture. The mixture was mechanically stirred at 20 ℃ for 1 hour with a dispersing blade mixer (10L from Chienemei Industry co. The cathode material is separated from the aluminum foil while the anode material is peeled off the copper foil. After stirring, the structural member, copper foil and aluminum foil were removed through a screen having a 4mm mesh width to obtain a suspension comprising water and ethanol and an electrode material. After removing the structural member, the copper foil and the aluminum foil, the suspension was filtered to obtain an electrode material. The recovered electrode material was placed in an oven at 80 ℃ and dried at atmospheric pressure for 5 hours, resulting in a final yield of 91%. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 8

Assembly of full lithium ion soft package battery

Preparation of the Positive electrode

For the preparation of the positive electrode, 94 wt.% of cathode material LiNi was added_0.33Mn_0.33Co_0.33O₂(NMC333) (available from Shenzhen Tianjiao Technology Co. Ltd., China), 3 wt.% of carbon black as a conductive agent (SuperP; available from Bordi Mimo high Co., Ltd., Switzerland) and 1.5 wt.% of polyacrylic acid as a binder (PAA, #181285, available from Paa, Mei)Available from sigma-aldrich) and 1.5 wt.% polyacrylonitrile (LA 132, genuineness dney power technology limited) were dispersed in deionized water to form a slurry with 50 wt.% solids content. The slurry was then uniformly coated on an aluminum foil as a current collector using a blade coater and dried at 50 ℃ for 12 hours to obtain a cathode aluminum sheet.

Preparation of the negative electrode

For the preparation of the negative electrode, 90 wt.% of hard carbon (HC; purity 99.5%, obtained from chinese rapford technologies ltd.) and 1.5 wt.% of CMC (BSH-12, DKS corporation, japan) and 3.5 wt.% of SBR (AL-2001, japan a & L company) as binders and 5 wt.% of carbon black as a conductive agent were dispersed in deionized water to form another slurry having a solid content of 50 wt.%. The slurry was then uniformly applied to a copper foil as a current collector using a blade coater and dried at 50 ℃ for 12 hours to obtain an anode copper sheet.

Assembly of pouch cells

After drying, the obtained cathode sheet and anode sheet were prepared into a cathode sheet and an anode sheet having a size of 8cm × 12cm, respectively, by cutting into square sheets. The cathode sheets and the anode sheets were stacked in an alternating manner with a 25 μm thick porous polyethylene separator (seikadard LLC, usa) therebetween to prepare a pouch cell. The electrolyte is LiPF in a mixture of Ethylene Carbonate (EC), Ethyl Methyl Carbonate (EMC) and dimethyl carbonate (DMC) in a volume ratio of 1:1:1₆(1M) of a solution. The battery has humidity and oxygen content<1ppm of high purity argon atmosphere. After the electrolyte filling, the pouch cell was vacuum sealed and then mechanically pressed using a punching die having a standard shape.

The assembled pouch cells were then subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.2V to simulate a realistic usage pattern. The actual battery capacity was about 5.1 Ah. After 900 cycles, the rated capacity drops below 80% of its original rated capacity.

Battery recycling

The used lithium ion battery (0.5kg) was completely discharged by soaking in 6% NaCl solution for 12 hours. After discharge, the lithium ion battery was chopped into chips by a water jet cutter (YCWJ-3038-L2015-1D, from YC industrial ltd, Jiangsu, China). Pieces of chopped lithium ion batteries having an average length of about 0.5 inches to about 1.0 inches were immersed into a mixture of deionized water (5L) and acetone (1L) at 20 ℃ to form a heterogeneous mixture. The mixture was mechanically stirred at 20 ℃ for 1 hour with a dispersing blade mixer (10L, from Chienemei Industry co. The cathode material is separated from the aluminum foil while the anode material is peeled off the copper foil. After stirring, the structural member, copper foil and aluminum foil were removed through a screen having a 4mm mesh width, thereby obtaining a suspension comprising water and acetone and an electrode material. After removing the structural member, the copper foil and the aluminum foil, the suspension was filtered to obtain an electrode material. The recovered electrode material was placed in an oven at 75 ℃ and dried at atmospheric pressure for 5 hours, resulting in a final yield of 92%. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 9

The pouch cell was prepared in the same manner as in example 1, except that a cathode material, LiNi, was used_0.6Mn_0.2Co_0.2O₂(NMC622) (from Hunan Rui xing New Material co., ltd., Changsha, china) instead of NMC 333. The assembled pouch cells were subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.2V to simulate a realistic usage pattern. The actual battery capacity was about 5.5 Ah. After 1,879 cycles, the rated capacity dropped below 80% of its original rated capacity.

The used lithium ion battery was recovered by the same method as in example 1. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 10

The pouch cell was prepared in the same manner as in example 1, except that a cathode material, LiNi, was used_0.8Mn_0.1Co_0.1O₂(NMC811) (from Henan Kelong new energy co., ltd., Xinxiang, china) instead of NMC 333. The assembled pouch cells were subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.2V to simulate a realistic usage pattern. The actual battery capacity was about 4.7 Ah. After 1,270 cycles, the rated capacity drops below 80% of its original rated capacity.

The used lithium ion battery was recovered by the same method as in example 1. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 11

The pouch cell was prepared in the same manner as in example 1, except that a cathode material, LiNi, was used_0.8Co_0.15Al_0.05O₂(NCA) (from Hunan Rui Xiing New Material Co., Ltd., Changsha, China) in place of NMC 333. The assembled pouch cells were subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.2V to simulate a realistic usage pattern. The actual battery capacity was about 4.2 Ah. After 996 cycles, the rated capacity dropped below 80% of its original rated capacity.

The used lithium ion battery was recovered by the same method as in example 1. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 12

The pouch cell was prepared in the same manner as in example 1. The used lithium ion battery was recovered in the same manner as in example 1 except that the rotation speed of the mixing paddle was 4,000rpm instead of 15,000 rpm. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 13

The pouch cell was prepared in the same manner as in example 1. The used lithium ion battery was recovered in the same manner as in example 12, except that the stirring time was 0.16 hours instead of 1 hour. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 14

The pouch cell was prepared by the same method as example 1 except that the cathode material LCO was used instead of NMC 333. The assembled pouch cells were subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.2V to simulate a realistic usage pattern. The actual battery capacity was about 3 Ah. After 1,300 cycles, the rated capacity drops below 80% of its original rated capacity.

The used lithium ion battery was recovered by the same method as in example 3, except that a high shear mixer was used instead of the dispersion paddle mixer, and the stirring time was 0.5 hours instead of 2 hours. The rotation speeds of the screw and the rotating member were 2,000rpm and 250rpm, respectively. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 15

The pouch cell was prepared by the same method as example 1 except that the cathode material LFP was used instead of NMC 333. The assembled pouch cells were subjected to repeated charge and discharge cycles at a constant current rate of 1C between 3.0V and 4.2V to simulate a realistic usage pattern. The actual battery capacity was about 15 Ah. After 2,100 cycles, the rated capacity drops below 80% of its original rated capacity.

The used lithium ion battery was recovered by the same method as in example 14. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 16

The pouch cell was prepared in the same manner as in example 1. The used lithium ion battery was recovered by the same method as in example 14. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Examples 17 to 20

The pouch cell was prepared by the same method as in example 1 except that NMC532, NMC622, NMC811 and NCA were used instead of NMC333 in examples 17, 18, 19 and 20, respectively. The used lithium ion battery was recovered by the same method as in example 14. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 21

The pouch cell was prepared in the same manner as in example 14. The used li-ion battery was recovered in the same manner as in example 5, except that a conical screw mixer (from shuangglong Group co., Ltd.) was used in place of the dispersing blade mixer. The rotation speed of the arm is 150rpm and the rotation speed of the screw is 300 rpm. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 22

The pouch cell was prepared in the same manner as in example 15. The used lithium ion battery was recovered by the same method as in example 21. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 23

The pouch cell was prepared in the same manner as in example 14. The used lithium ion battery was recovered in the same manner as in example 5, except that a planetary stirring mixer was used instead of the dispersion paddle mixer. The rotation speeds of the planetary paddle and the high-speed dispersing paddle were 150rpm and 1,000rpm, respectively. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 24

The pouch cell was prepared in the same manner as in example 15. The used lithium ion battery was recovered by the same method as in example 23. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 25

The pouch cell was prepared in the same manner as in example 14. The used li-ion cells were recovered in the same manner as in example 5, except that an air jet mixer (from ALPA Powder Technology & Equipment co., Ltd.) was used in place of the dispersing paddle mixer. The pressure of the air jet was 0.3 MPa. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 26

The pouch cell was prepared in the same manner as in example 15. The used lithium ion battery was recovered by the same method as in example 25. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 27

The pouch cell was prepared in the same manner as in example 14. The used lithium ion battery was recovered in the same manner as in example 1, except that 30g of plastic beads having a size of 0.5mm were additionally added to the heterogeneous mixture; the speed of the dispersing paddle mixer was 4,000rpm instead of 15,000 rpm; and the stirring time was 0.5 hours instead of 1 hour. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 28

The pouch cell was prepared in the same manner as in example 1. The used lithium ion battery was recovered by the same method as in example 27. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Example 29

The pouch cell was prepared in the same manner as in example 10. The used lithium ion battery was recovered by the same method as in example 27. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative example 1

The pouch cell was prepared in the same manner as in example 15. The used lithium ion battery was recovered in the same manner as in example 1, except that the chopped battery was soaked for 1 hour without stirring. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative example 2

The pouch cell was prepared in the same manner as in example 4. The used lithium ion battery was recovered in the same manner as in example 4, except that 20kg of the used battery was used instead of 0.5kg, and the volume of water was changed to 25L. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative example 3

The pouch cell was prepared in the same manner as in example 1. The used lithium ion battery was recovered in the same manner as in example 4, except that the amount of water was 5L instead of 10L, and the heterogeneous mixture was stirred for 2 hours instead of 0.5 hour. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative example 4

The pouch cell was prepared in the same manner as in example 10. The used lithium ion battery was recovered by the same method as in comparative example 3, and the recovery conditions and formulation of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative example 5

The pouch cell was prepared in the same manner as in example 5. The used lithium ion battery was recovered in the same manner as in example 5, except that 20kg of the used battery was used instead of 0.5 kg; the volume of water was changed to 25L; and the heterogeneous mixture was stirred using a stirring mixer and an ultrasonic bath instead of a dispersion paddle mixer. The stirring speed of the stirring mixer was 500rpm and the input power of the ultrasonic bath was 200W. The heterogeneous mixture was continuously stirred and sonicated for 20 minutes. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative example 6

The pouch cell was prepared by the same method as example 5 except that cathode material NMC811 was used instead of LCO. The used lithium ion battery was recovered by the same method as in comparative example 5, except that the amount of water was changed to 5L instead of 25L and 0.5kg of the used lithium ion battery was used instead of 20 kg. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative example 7

The pouch cell was prepared in the same manner as in example 15. The used lithium ion battery was recovered in the same manner as in comparative example 6, except that the stirring time was 1 hour instead of 20 minutes. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative example 8

The pouch cell was prepared in the same manner as in example 14. Used lithium ion batteries (0.1kg) were recovered using an impact crusher (PLS-550 from luoyang dahua Heavy Type Machinery co., ltd., china) at 2,500rpm for 0.011 hours. The volume of water used was 1L. After stirring, the structural member, copper foil and aluminum foil were removed through a screen having a 4mm mesh width, thereby obtaining a suspension comprising water and an electrode material. After removing the structural member, the copper foil and the aluminum foil, the suspension was filtered to obtain an electrode material. The recovered electrode material was placed in an oven at 80 ℃ and dried at atmospheric pressure for 5 hours. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative examples 9 to 11

The manufacturing methods of the pouch batteries of comparative examples 9, 10 and 11 were the same as those of examples 15, 1 and 10, respectively. The method for recovering the used lithium ion batteries of comparative examples 9, 10 and 11 was the same as comparative example 8. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative example 12

The pouch cell was prepared in the same manner as in example 14. The used li-ion battery was recovered in the same manner as in example 5, except that a screw mixer (from shuangglong groupco., Ltd) was used instead of the dispersing paddle mixer. The rotational speed of the screw was 500 rpm. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative examples 13, 14 and 15

The manufacturing methods of the pouch batteries of comparative examples 13, 14 and 15 were the same as those of examples 15, 1 and 10, respectively. The method for recovering the used lithium ion batteries of comparative examples 13, 14 and 15 was the same as comparative example 12. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative examples 16 and 17

The manufacturing methods of the pouch batteries of comparative examples 16 and 17 were the same as those of examples 1 and 10, respectively. The used lithium ion batteries of comparative examples 16 and 17 were recovered by the same method as in example 21. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative examples 18 and 19

The manufacturing methods of the pouch batteries of comparative examples 18 and 19 were the same as those of examples 1 and 10, respectively. The used lithium ion batteries of comparative examples 18 and 19 were recovered by the same method as in example 23. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Comparative examples 20 and 21

The manufacturing methods of the pouch batteries of comparative examples 20 and 21 were the same as those of examples 1 and 10, respectively. The method for recovering the used lithium ion batteries of comparative examples 20 and 21 was the same as in example 25. The recovery conditions and formulations of the cathode and anode are shown in table 1. The recovery results are shown in table 3.

Reference example 1

The manufacturing method of the pouch battery of reference example 1 was the same as example 1. The used lithium ion battery was disassembled and 1kg of cathode electrode was separated. The separated cathode electrode was immersed in 5L of deionized water at 20 ℃ and the resulting mixture was stirred by a high shear mixer for 0.5 hour. The rotational speed of the rotating member was 250rpm, and the rotational speed of the screw was 2,000 rpm. The cathode material was peeled from the aluminum foil. After stirring, the aluminum foil was removed through a screen having a 4mm mesh width, thereby obtaining a suspension comprising water and an electrode material. After removing the aluminum foil, the suspension was filtered to obtain an electrode material. The recovered electrode material was placed in an oven at 80 ℃ and dried at atmospheric pressure for 5 hours. The recovery conditions and formulations of the cathodes are shown in table 2. The recovery results are shown in table 3.

Reference example 2

The manufacturing method of the pouch battery of reference example 2 was the same as that of example 10. The used lithium ion battery was disassembled and 1kg of cathode electrode was separated. The recovery method of the separated cathode electrode was the same as in reference example 1. The recovery conditions and formulations of the cathodes are shown in table 2. The recovery results are shown in table 3.

Reference example 3

The manufacturing method of the pouch battery of reference example 3 was the same as example 1. The used lithium ion battery was disassembled and 1kg of cathode electrode was separated. The recovery method of the separated cathode electrode was the same as in reference example 1 except that a dispersion paddle mixer was used instead of the high shear mixer. The rotation speed of the mixing paddle was 15,000 rpm. The recovery conditions and formulations of the cathodes are shown in table 2. The recovery results are shown in table 3.

Reference example 4

The manufacturing method of the pouch battery of reference example 4 was the same as example 1. The used lithium ion battery was disassembled and 1kg of anode electrode was separated. The recovery method of the separated anode electrode was the same as in reference example 1. The recovery conditions and formulations of the anodes are shown in table 2. The recovery results are shown in table 3.

Reference example 5

The manufacturing method of the pouch battery of reference example 5 was the same as example 1. The used lithium ion battery was disassembled and 1kg of anode electrode was separated. The recovery method of the separated anode electrode was the same as in reference example 3. The recovery conditions and formulations of the anodes are shown in table 2. The recovery results are shown in table 3.

TABLE 1

Note that:¹the rotation speed of the dispersing paddle mixer was 4,000rpm

²The dispersion paddle mixer was rotated at 4,000rpm and plastic beads (30g) were added to the heterogeneous mixture

³The shredded battery was immersed in water for 1 hour without agitation

TABLE 2

The yield of the recovered electrode material is shown in table 3 below. The methods disclosed herein can improve the recovery efficiency of different types of cathode materials. High nickel cathode material may also be recovered.

TABLE 3

While the invention has been described with respect to a limited number of embodiments, the specific features described in one embodiment should not be used to limit other embodiments of the invention. In some embodiments, the method may include a number of steps not mentioned herein. In other embodiments, the method does not include or is substantially free of any steps not recited herein. Variations and modifications exist in the described embodiments. It is intended that the appended claims cover all such modifications and variations as fall within the scope of this present invention.

Claims (20)

1. A method of recycling a lithium ion battery, comprising the steps of:

a) discharging the lithium ion battery;

b) shredding the lithium ion battery into pieces to provide a mixture of a structural component, a first electrically conductive metal component coated with a cathode layer, and a second electrically conductive metal component coated with an anode layer;

c) immersing the shredded fragments of lithium ion batteries into a polar solvent to form a heterogeneous mixture;

d) treating the heterogeneous mixture with mechanical agitation for a period of about 30 minutes to about 5 hours to dissolve the binder material in the cathode layer and the anode layer;

e) screening the treated heterogeneous mixture to separate the structural component, the first electrically conductive metal component, and the second electrically conductive metal component from a finer electrode material comprising cathode and anode materials to provide a suspension comprising the polar solvent and the finer electrode material; and

f) separating the finer electrode material in the suspension from the polar solvent;

wherein the polar solvent is water, an alcohol, a ketone, or a combination thereof;

wherein the cathode material is selected from the group consisting of LiCoO₂、LiNiO₂、LiNi_xMn_yO₂、LiNi_xCo_yO₂、Li_1+zNi_xMn_yCo_{1-x- y}O₂、LiNi_xCo_yAl_zO₂、LiV₂O₅、LiTiS₂、LiMoS₂、LiMnO₂、LiCrO₂、LiMn₂O₄、LiFeO₂、LiFePO₄And combinations thereof; wherein each x is independently 0.3 to 0.8; each y is independently 0.1 to 0.45; and each z is independently 0 to 0.2; and

wherein the binder material of each of the cathode layer and the anode layer is independently a water-based binder material or a mixture of a water-based binder material and an organic binder material.

2. The method of claim 1, wherein the cathode material is selected from the group consisting of LiNiO₂、LiNi_xMn_yO₂、LiNi_xCo_yO₂、Li_1+zNi_xMn_yCo_1-x-yO₂、LiNi_xCo_yAl_zO₂Nickel-rich cathode materials and combinations thereof; wherein each x is independently 0.5 to 0.8; each y is independentlyFrom 0.1 to 0.4; and each z is independently 0 to 0.2.

3. The method of claim 2, wherein the nickel-rich cathode material is LiNi_0.8Mn_0.2O₂、LiNi_0.6Mn_0.4O₂、LiNi_0.8Co_0.2O₂、LiNi_0.6Co_0.4O₂NMC532, NMC622, NMC811, NCA or combinations thereof.

4. The method of claim 1, wherein the shredded pieces of lithium ion battery have an average length of about 0.5 inches to about 4.0 inches or about one-quarter inches or less.

5. The method of claim 1, wherein each of the first and second electrically conductive metal parts is independently selected from the group consisting of aluminum sheet, copper sheet, gold sheet, silver sheet, and platinum sheet.

6. The method of claim 1, wherein the polar solvent further comprises a salt selected from the group consisting of lithium carbonate, lithium bicarbonate, lithium phosphate, sodium carbonate, sodium bicarbonate, sodium phosphate, potassium carbonate, potassium bicarbonate, potassium phosphate, ammonium carbonate, ammonium bicarbonate, ammonium phosphate, and combinations thereof.

7. The method of claim 6, wherein the polar solvent has a pH of about 6 to about 8.

8. The method of claim 1, wherein the alcohol is selected from methanol, ethanol, isopropanol, n-propanol, tert-butanol, or a combination thereof.

9. The method of claim 1, wherein the weight ratio of the water to the alcohol is from about 5:95 to about 95: 5.

10. The method of claim 1, wherein the mechanically agitating step is performed by an agitator, an ultrasonic generator, or a combination thereof.

11. The method of claim 10, wherein the agitator is a high shear mixer, a planetary mixer, or a stirred mixer, and wherein the sonicator is an ultrasonic bath or an ultrasonic probe.

12. The method of claim 1, wherein the mechanical agitation of step d) is performed at room temperature.

13. The method of claim 1, wherein the heterogeneous mixture in step d) is heated at a temperature of about 35 ℃ to about 100 ℃ or about 55 ℃ to about 75 ℃.

14. The method of claim 1, wherein the water-based binder material is selected from the group consisting of styrene-butadiene rubber, acrylated styrene-butadiene rubber, acrylonitrile-butadiene rubber, nitrile-butadiene rubber, acrylonitrile-styrene-butadiene copolymer, polybutadiene, polyvinylpyrrolidone, polyvinylpyridine, polyvinyl alcohol, polyvinyl acetate, polyacrylonitrile, cellulose, carboxymethyl cellulose, hydroxypropyl cellulose, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl cellulose, polyacrylic acid, polyacrylate, polymethacrylic acid, polymethacrylate, polyacrylamide, alginate, and combinations thereof.

15. The method of claim 1, wherein the organic binder material is selected from the group consisting of polytetrafluoroethylene, perfluoroalkoxy polymers, polyvinylidene fluoride, copolymers of tetrafluoroethylene and hexafluoropropylene, fluorinated ethylene-propylene copolymers, tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride terpolymers, and combinations thereof.

16. The method of claim 1, wherein the finer electrode material further comprises a conductive agent.

17. The method of claim 1, wherein the finer electrode material is screened through a screen having a mesh width of 2mm-4mm or 0.5mm-1.0 mm.

18. The method of claim 1, wherein the separation of the finer electrode material is performed via filtration, decantation, sedimentation, centrifugation, or a combination thereof.

19. The method of claim 1, wherein the recovery of the finer electrode material is at least 90% or at least 95%.

20. The method of claim 1, wherein the impurity percentage of the recovered finer electrode material is less than 2%, less than 1%, less than 0.5%, less than 0.1%, or less than 0.05%.