FR3161074A1 - Process for purifying a leaching filtrate from the black mass of lithium-ion batteries - Google Patents

Abstract

Process for Purifying a Leach Filtrate from the Black Mass of Lithium-ion Batteries The present invention relates to a process for purifying a leach filtrate from the black mass of lithium-ion batteries, said filtrate containing lithium and at least one solubilized organic compound, said process comprising the step of adding an oxidizing agent, a Fenton catalyst, and optionally a phosphate salt to said filtrate so as to obtain a solution containing lithium and depleted in said at least one solubilized organic compound.

Description

Process for purifying a leaching filtrate from the black mass of lithium-ion batteries

The present invention relates to the general field of recycling used lithium-ion batteries or lithium-ion battery production waste and in particular the recovery of lithium and possibly other valuable metals present in these batteries or waste, such as cobalt, nickel, manganese and their mixtures.

It particularly concerns the purification of the leaching filtrate from the black mass of lithium-ion batteries in order to eliminate organic impurities and recover lithium and possibly other valuable metals.

When recycling used lithium-ion batteries, after separating the plastics, the parts containing the electrodes such as the battery cells are crushed or shredded to produce a powdery metallic fraction called "black mass".

Similarly, during the lithium-ion battery manufacturing process, semi-finished products such as active material powders or non-compliant batteries considered as production scrap may be produced and should be recycled. These products can be treated in the same way as used lithium-ion batteries and will contribute to the production of the metallic powder fraction called "black mass".

It is generally known to dissolve the black mass in sulfuric acid in the presence of an oxidative-reducing reagent in order to maximize the dissolution yield and thus obtain a leachate, the liquid part of which after the implementation of a solid/liquid separation step is called leaching filtrate.

This black mass leaching filtrate contains lithium and possibly other valuable metals such as nickel, cobalt and/or manganese which are of interest to recover, but also solubilized organic compounds which should be eliminated, the most common being ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), dimethoxyethane (DME), N-methyl-2-pyrrolidone (NMP), etc.

These organic compounds, and their degradation products, are in fact considered impurities in the process and must be removed from the leaching filtrate. For convenience, the indicator for monitoring the presence of these compounds is the concentration of total organic carbon (TOC), which groups together all the organic compounds that can coexist within a solution.

It would therefore be interesting to have a process to eliminate these organic compounds and thus reduce the concentration of total organic carbon in the leaching filtrate while avoiding the production of new polluting products.

The inventors realized that it was possible to use a "Fenton" type reaction, that is to say, the chemical degradation of these compounds in order to produce water and _CO2 in the presence of a Fenton catalyst.

In particular, the Fenton catalyst can consist of materials from the lithium ion batteries themselves when the latter are Lithium-Iron-Phosphate batteries, which is particularly interesting because it also participates in the recycling of said batteries and makes it possible to recover the lithium present in these batteries.

Furthermore, this reaction can be implemented at any point in the purification process but is particularly advantageous when it is implemented after the step of purification of the leaching filtrate by Al/Fe precipitation with lime because the pH range and temperature are favorable.

Finally, the inventors surprisingly discovered that this reaction is improved when carried out in the presence of a phosphate salt because this allows the TOC to be reduced more significantly and therefore promotes the depletion of the solution in solubilized organic compound.

The present invention therefore relates to a method for purifying a leaching filtrate from the black mass of lithium-ion batteries, said filtrate containing lithium and at least one solubilized organic compound, said method comprising the step of adding an oxidizing agent, a Fenton catalyst, and optionally a phosphate salt to said filtrate so as to obtain a solution containing lithium and depleted in said at least one solubilized organic compound.

In this application, the expressions “between ... and ...”, “from ... to ...” and “in the range ...- ...”, must be understood to include limits unless explicitly stated otherwise.

According to the present invention, the term “solution depleted in said at least one solubilized organic compound” means that the solution contains a lower quantity of said at least one solubilized organic compound than the quantity initially present before the implementation of the step, advantageously a TOC concentration lower than that initially present before the implementation of the step. The TOC concentration can be measured by a TOC meter according to standard NF 1484. In particular, the TOC concentration eliminated by the process according to the invention can be between 5% and 90%, advantageously between 10% and 90%, more advantageously between 18% and 88%.

The lithium-ion batteries according to the invention may comprise, and advantageously consist of, Lithium-Iron-Phosphate (LFP) type batteries in which the electrodes are made of mixed lithium and iron phosphate (LiFePO ₄ ) and graphite, or LFP/LTO (Lithium-Iron-Phosphate/Lithium-Titanium-Oxide) type batteries, in which the electrodes are made of mixed lithium and iron phosphate and mixed lithium and titanium oxide (Li ₄ Ti ₅ O ₁₂ ), or Nickel Cobalt Aluminum (NCA) batteries or Nickel Manganese Cobalt (NMC) batteries or even batteries comprising at least one of the three elements nickel, cobalt or manganese.

For the purposes of the present invention, the term "black mass" or "black mass" means the powdery fraction containing fine metal particles obtained after separation of plastic materials and grinding/processing of parts containing electrodes such as battery cells, used lithium-ion batteries and/or lithium-ion battery scrap (non-compliant lithium-ion batteries or semi-finished products manufactured during the lithium-ion battery manufacturing process). Typically, the black mass is obtained by screening to 500 µm or less. There are two main processing routes used for the production of the black mass:
- heat treatment processes at temperatures > 400°C. A black mass called “thermal black mass” or “thermal black mass” is obtained and
- high-intensity mechanical treatments. A black mass called “mechanical black mass” or “mechanical black mass” is obtained. The black mass according to the invention can therefore consist of a thermal black mass, a mechanical black mass, or a mixture of thermal black mass and mechanical black mass in any proportion.

The black mass contains lithium but may also contain other valuable metals such as nickel, cobalt and/or manganese. Despite the separation of plastics, it also contains organic compounds such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, dimethoxyethane, N-methyl-2-pyrrolidone, carboxy methyl cellulose and mixtures thereof. It may also contain many other impurities such as aluminum, calcium, iron, fluorine, phosphorus and/or copper. It may also contain magnesium. It also contains graphite. The typical composition of a black mass (thermal or mechanical) apart from the carbon content is shown in Table 1 below:

Elements % by mass [COT] ≤ 2 Li 2-6 Neither 10-30 Co 3-9 Mn 3-9 Al 1-3 That 0-2 Mg 0-2 Cu 2-6 Fe 0-3 F 1-8 PO ₄ ^3- 0-2

For the purposes of the present invention, the term "black mass leaching filtrate" means the liquid part resulting from the leaching of the black mass. In general, the leaching is carried out with sulfuric acid in the presence of an oxidizing-reducing compound and the leaching step is followed by a solid/liquid separation step (advantageously by filtration) in order to recover the liquid part, thus called the black mass leaching filtrate.

In the context of the present invention, this leaching filtrate may be the liquid part directly resulting from the solid/liquid separation after leaching of the black mass, but it may also be the liquid part obtained after one or more purification steps which follow/follow this solid/liquid separation. Thus, advantageously, this leaching filtrate corresponds to the liquid part obtained after a purification step by precipitation of Al/Fe, in particular with lime.

Thus, the process according to the present invention may comprise a preliminary step of purification by precipitation of Al/Fe, in particular with lime, and recovery of the liquid part. The recovery of the liquid part may be carried out by any solid/liquid separation methods known to those skilled in the art, such as filtration, decantation, centrifugation, etc.

The method according to the present invention may also comprise, before this purification step or before the addition step according to the present invention if this preliminary purification step is not present, a step of leaching the black mass of lithium-ion batteries followed by a solid/liquid separation step in order to recover the liquid part. The recovery of the liquid part may be carried out by any solid/liquid separation methods known to those skilled in the art such as filtration, decantation, centrifugation, etc. In particular, the black mass may be a mixture of thermal black mass and mechanical black mass, in particular in a mass ratio of 50/50. Advantageously, this leaching step is carried out by a method well known to those skilled in the art, more advantageously using an acid, such as sulfuric acid H ₂ SO ₄ . Advantageously, the quantity in moles of acid is calculated to correspond to a molar ratio H ⁺ /(Li+Co+Ni+Mn) necessary for the dissolution of lithium and possibly cobalt, manganese and/or nickel present in the black mass, in particular between 90 and 150%, preferably between 110 and 130%. In particular, the pH is less than 2. More particularly, the temperature is greater than 50°C, in particular greater than 70°C, more particularly it is 90°C. Advantageously, the leaching step lasts 4 hours. Advantageously, the leaching step is carried out in the presence of an oxido-reducing compound, in particular a reducing compound, more advantageously chosen from hydrogen peroxide, SO ₂ in gas form and their mixtures, in particular, it is SO ₂ in gas form. In particular, the content of redox compound used is that necessary to adjust the redox potential in a range between 200 and 800 mV vs Ag/AgCl, more advantageously between 200 and 700 mV vs Ag/AgCl, more particularly between 200 and 600 mV vs Ag/AgCl. In an advantageous embodiment, the acid is added to a first reactor and the redox compound to a second reactor. The mass yield of lithium and optionally nickel and/or cobalt and/or manganese leaching (calculated according to the following formula: 1 - mass of the element (in g) in solid form obtained at the end of the leaching step/ initial mass of element (in g) in the filtrate before the leaching step) is advantageously greater than 90%, more advantageously greater than 95%, even more advantageously greater than 99%.

The leaching filtrate of the black mass according to the invention, more simply called “leaching filtrate” in the remainder of the application, contains lithium. It may contain at least one other valuable metal, advantageously chosen from nickel, cobalt and their mixtures. Advantageously, it is a mixture of lithium (Li), nickel (Ni), manganese (Mn) and cobalt (Co). The lithium, and possibly nickel, cobalt and/or manganese, contents of the leaching filtrate according to the invention depend on the contents present in the black mass and the contents which may have been lost during any previous purification steps.

The lithium content of the leaching filtrate according to the invention can thus be ≤ 15g/l, more advantageously between 5 g/l and 14 g/l, in particular between 9 g/l and 11g/l.

The nickel content of the leaching filtrate according to the invention, if nickel is present, can thus be in the range 10-60 g/l, more advantageously between 30 g/l and 55 g/l, in particular between 44 g/l and 48 g/l.

The cobalt content of the leaching filtrate according to the invention, if cobalt is present, can thus be in the range 1-40 g/l, more advantageously between 5 g/l and 20 g/l, in particular between 12 g/l and 15 g/l.

The manganese content of the leaching filtrate according to the invention, if manganese is present, may be ≤ 50 g/l, more advantageously between 5 g/l and 30 g/l, in particular between 12 g/l and 15 g/l.

The leaching filtrate according to the invention contains at least one solubilized organic compound, the compound which it is sought to eliminate. Advantageously, the at least one organic compound is chosen from the group consisting of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, dimethoxyethane, N-methyl-2-pyrrolidone, carboxy methyl cellulose and mixtures thereof.

The concentration of total organic carbon (TOC), in particular measured by a TOC meter according to standard NF 1484, of the leaching filtrate according to the invention is advantageously between 10 mg/l and 5000 mg/l, advantageously between 600 mg/l and 3000 mg/l.

The leaching filtrate according to the invention may contain other impurities such as aluminum (Al), calcium (Ca), fluorine (F), magnesium (Mg), iron (Fe), phosphorus (P) and/or copper (Cu). The contents of aluminum (Al), calcium (Ca), fluorine (F), magnesium (Mg), iron (Fe), phosphorus (P) and/or copper (Cu) in the leaching filtrate according to the invention depend on the contents present in the black mass and on the quantities removed during any prior purification steps.

The aluminium content of the leaching filtrate according to the invention, if aluminium is present, can thus be ≤ 20 g/l, more advantageously between 1 g/l and 10 g/l, in particular between 2 g/l and 4 g/l. Advantageously, if the filtrate is obtained after a purification step by precipitation of Al/Fe, the aluminium content will be < 100 mg/l.

The calcium content of the leaching filtrate according to the invention, if calcium is present, can thus be ≤ 0.7 g/lg/l, more advantageously between 0.2 g/l and 0.6 g/l, in particular between 0.3 g/l and 0.5 g/l.

The fluorine content of the leaching filtrate according to the invention, if fluorine is present, can thus be ≤ 20 g/l, more advantageously between 4 g/l and 10 g/l, in particular between 6 g/l and 8 g/l.

The magnesium content of the leaching filtrate according to the invention, if magnesium is present, can thus be ≤ 5 g/l, more advantageously between 3 g/l and 4 g/l.

The iron content of the leaching filtrate according to the invention, if iron is present, can thus be ≤ 10 g/l, more advantageously between 0.5 g/l and 5 g/l, in particular between 1 g/l and 2 g/l. Advantageously, if the filtrate is obtained after a purification step by precipitation of Al/Fe, the iron content will be < 2 mg/l.

The phosphorus content in the form of PO ₄ ^3- of the leaching filtrate according to the invention, if phosphorus is present, can thus be ≤ 10 g/l, more advantageously between 0.1 g/l and 5 g/l, in particular between 0.5 g/l and 4 g/l.

The copper content of the leaching filtrate according to the invention, if copper is present, can thus be ≤ 30 g/l, more advantageously between 2 g/l and 20 g/l, in particular between 9 g/l and 11 g/l.

The process according to the invention is carried out by adding an oxidizing agent, a Fenton catalyst, and optionally a phosphate salt to the leaching filtrate according to the invention. The reactants can be added in any order. Preferably, if present, the phosphate salt is added first, then the Fenton catalyst and finally the oxidizing agent.

Advantageously, the oxidizing agent according to the invention is the usual one for Fenton reactions, in particular chosen from the group consisting of sodium persulfate, ozone, air, O ₂ , hydrogen peroxide and their mixtures, advantageously it is hydrogen peroxide in particular at between 30 and 35%.

The quantity of oxidizing agent added depends on the TOC concentration of the filtrate according to the invention and advantageously the oxidizing agent/TOC molar ratio is between 1 and 50, preferably between 1 and 25, more advantageously between 2 and 10.

For the purposes of the present invention, the term “Fenton catalyst” means all catalysts that can be used to catalyze Fenton-type reactions.

Advantageously, the Fenton catalyst according to the invention is chosen from the group consisting of a source of iron, UV radiation, ozone and their mixtures, advantageously it is a source of iron, alone or in a mixture with UV radiation or ozone, more advantageously it is a source of iron alone.

Advantageously, the iron source is selected from the group consisting of iron II sulfate (FeSO ₄ ), iron II phosphate, lithium iron phosphate, in the form of the compound LiFePO ₄ as such or in the form of materials for or derived from lithium-iron-phosphate batteries, iron metal (Fe(0)) and mixtures thereof. Advantageously, this is iron II sulfate (FeSO ₄ ), iron metal (Fe(0)) or LiFePO ₄ .

In an advantageous embodiment, the iron source is lithium iron phosphate, in the form of the compound LiFePO ₄ as such or in the form of materials for or derived from lithium-iron-phosphate batteries.

Indeed, the use of materials for batteries or from LFP (Lithium-Iron-Phosphate) type batteries, in their cathodic form, pieces (scraps), or shredded used batteries is particularly interesting in the context of the present invention because it contributes to the recycling of said batteries.

The amount of Fenton catalyst added takes into account the elements already present in solution that can contribute positively or negatively to the reaction, called reactive elements. In particular, it is known that too large an excess of metallic elements such as iron or copper can have a negative impact on the reaction. Advantageously, the amount of Fenton catalyst added makes it possible to obtain a catalyst concentration (in g/l of reactive elements) in the filtrate according to the invention corresponding to between 0.1 and 10 g/L of reactive element, preferably between 0.1 and 1.5 g/l of reactive elements.

In a particularly advantageous embodiment, a phosphate salt is added to said filtrate in combination with the oxidizing agent and the Fenton catalyst.

Advantageously, it is sodium phosphate or lithium phosphate, in particular sodium phosphate. More particularly sodium phosphate dodecahydrate (Na ₃ PO ₄ .12H ₂ O).

The amount of phosphate salt added depends on the molar amount of aluminum and iron in the filtrate according to the invention.

The inventors surprisingly noticed that the addition of phosphate salt made it possible to further improve the elimination of solubilized organic compounds present in the filtrate according to the invention and therefore the depletion of this filtrate in solubilized organic compounds, i.e. the reduction of the TOC concentration.

In an advantageous embodiment, the addition step of the process according to the invention is carried out at a temperature between 10°C and 95°C, advantageously between 30°C and 90°C, more advantageously between 40°C and 80°C, even more advantageously between 50°C and 75°C, in particular it is 60°C. This temperature is advantageously maintained throughout the duration of the reaction between the reactants (oxidizing agent, Fenton catalyst and/or phosphate salt) and the leaching filtrate.

In another advantageous embodiment, the Fenton catalyst is a source of iron and the addition step of the process according to the invention is carried out on a filtrate having an initial pH of between 2 and 5, advantageously between 2.5 and 4.

For the purposes of the present invention, the term “initial pH of the leaching filtrate” means the pH of the leaching filtrate before carrying out the addition step according to the invention.

Advantageously, the pH is adjusted at the start of the reaction (i.e. during the addition step) and/or throughout the duration of the reaction between the reactants (oxidizing agent, Fenton catalyst and/or phosphate salt) and the leaching filtrate, advantageously by adding a base, in order to obtain the desired pH, in particular a pH between 2.5 and 4. Advantageously, the base is chosen from the group consisting of sodium hydroxide (NaOH) and lime (CaO), more advantageously it is lime.

In yet another advantageous embodiment, the method according to the invention comprises an additional step of solid/liquid separation in order to recover said solution containing lithium depleted in said at least one solubilized organic compound. This step can be implemented by any solid/liquid separation methods known to those skilled in the art such as filtration, decantation, centrifugation, etc. Advantageously, it is a filtration, in particular under pressure.

Advantageously, the reaction between the oxidizing agent, the Fenton catalyst and the optional phosphate salt with the at least one solubilized organic compound lasts between 10 minutes and 5 hours, in particular between 30 minutes and 3 hours, more advantageously between 1 hour and 2 hours.

In an advantageous embodiment, the method according to the present invention may comprise one or more steps intended to reduce the TOC concentration which may be prior to the addition step according to the invention, such as upstream drying of the black mass and/or filtration of the filtrates on suitable media known to those skilled in the art and/or treatment with compounds such as activated carbon, or even subsequent steps such as filtration of the filtrates on suitable media and/or treatment with compounds such as activated carbon.

Lithium and any other valuable metals present in the liquid part obtained with the process according to the invention can be recovered and separated by methods well known to those skilled in the art, in particular by neutralization and/or solvent extraction.

The present invention will be better understood upon reading the description of the examples which follow. The examples are given for informational purposes only and are not limiting. Unless otherwise stated in the examples, the pressure is atmospheric pressure and the temperatures are indicated in °C.

EXAMPLE

Table 2 below brings together the reaction conditions and the results obtained by implementing the process according to the invention on a leaching filtrate according to the invention obtained after purification by Al/Fe precipitation. It contains a lithium content between 3 and 5g/L.

The TOC concentration is measured by a TOC meter according to standard NF 1484.

Examples 1 to 18 are carried out using hydrogen peroxide as the oxidizing agent: H ₂ O ₂ at 30% in Examples 1 to 13 and H ₂ O ₂ at 35% in Examples 14 to 18.

Examples 1 to 7 and 14 to 18 are implemented using FeSO₄as source of iron.

Examples 8 to 10 are implemented using Fe(0) as source of iron.

Examples 11 to 13 are implemented using LiFePO₄as source of iron.

Example 14 is implemented with the further addition of 1.96 g of sodium phosphate dodecahydrate (Na ₃ PO ₄ .12H ₂ O).

Examples 1 to 4 are carried out without pH adjustment, Examples 5 to 18 are carried out with pH adjustment.

Examples 16 to 18 are carried out in the presence of a base (CaO at 10% by mass in the case of examples 16 and 17 and NaOH at 25% by mass in the case of example 18) in order to neutralize the pH.

Example 9 is implemented by simultaneous addition of the Fenton catalyst (Fe(0)) and the oxidizing agent (hydrogen peroxide).

Ex Filtrate quantity (ml) Quantity H ₂ O ₂ in g Quantity of Fe in g T reaction in °C Reaction time in h Initial pH Final pH % [TOC] removed after reaction (%) 1 30 0.5 1.5 50-75 2 0 < pH < 4 2 < pH < 5 57% 2 30 1 1.5 50-75 2 0 < pH < 4 2 < pH < 5 71% 3 30 0.5 0.75 50-75 2 0 < pH < 4 2 < pH < 5 44% 4 30 2 5 50-75 2 0 < pH < 4 2 < pH < 5 19% 5 50 4.8 1.5 50-75 2 0 < pH < 4 2 < pH < 5 71% 6 50 2.4 1.5 50-75 2 0 < pH < 4 2 < pH < 5 64% 7 50 2.4 1.5 50-75 2 0 < pH < 4 2 < pH < 5 74% 8 50 4.8 5.5 50-75 2 0 < pH < 4 2 < pH < 5 76% 9 50 4.8 5.5 50-75 2 0 < pH < 4 2 < pH < 5 83% 10 50 4.8 2 50-75 2 0 < pH < 4 2 < pH < 5 77% 11 50 4.8 5.5 50-75 2 0 < pH < 4 2 < pH < 5 69% 12 50 4.8 5.5 50-75 2 0 < pH < 4 2 < pH < 5 82% 13 50 2.4 1.5 50-75 2 0 < pH < 4 2 < pH < 5 42% 14 50 4.7 0.5 50-75 1.5 0 < pH < 4 2 < pH < 5 88% 15 50 4.7 0.5 50-75 1.5 0 < pH < 4 2 < pH < 5 44% 16 50 4.7 5.5 50-75 1.5 0 < pH < 4 2 < pH < 5 86% 17 50 4.7 5.5 50-75 1.5 0 < pH < 4 2 < pH < 5 85% 18 50 4.7 5.5 50-75 1.5 0 < pH < 4 2 < pH < 5 87%

It should be noted that the presence of a phosphate salt such as sodium phosphate makes it possible to improve the process according to the invention since the TOC elimination increases from 44% (example 15) when it is not present to 88% (example 14) when it is present. There is therefore a very significant reduction in this concentration in the presence of this agent.

The method according to the present invention is therefore particularly effective in depleting the leaching filtrate of solubilized organic compound and therefore reducing the TOC concentration.

Claims (12)

A method for purifying a leaching filtrate from the black mass of lithium-ion batteries, said filtrate containing lithium and at least one solubilized organic compound, said method comprising the step of adding an oxidizing agent, a Fenton catalyst, and optionally a phosphate salt to said filtrate so as to obtain a solution containing lithium and depleted in said at least one solubilized organic compound. Process according to claim 1, characterized in that the phosphate salt, advantageously sodium phosphate, is added to said filtrate in combination with the oxidizing agent and the Fenton catalyst. Process according to any one of claims 1 or 2, characterized in that the filtrate contains at least one other valuable metal, advantageously chosen from nickel, cobalt and their mixtures. Process according to any one of claims 1 to 3, characterized in that the at least one organic compound is chosen from the group consisting of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, dimethoxyethane, N-methyl-2-pyrrolidone, carboxy methyl cellulose and mixtures thereof. Method according to any one of claims 1 to 4, characterized in that the oxidizing agent is chosen from the group consisting of sodium persulfate, ozone, air, O ₂ , hydrogen peroxide and mixtures thereof, advantageously it is hydrogen peroxide. Process according to any one of claims 1 to 5, characterized in that the Fenton catalyst is chosen from the group consisting of a source of iron, UV radiation, ozone and their mixtures, advantageously it is a source of iron alone. Method according to claim 6, characterized in that the source of iron is chosen from the group consisting of iron II sulfate, iron II phosphate, lithium iron phosphate, in the form of the compound LiFePO ₄ as such or in the form of materials for or derived from lithium-iron-phosphate batteries, iron metal and their mixtures. Process according to any one of claims 1 to 7, characterized in that the addition step is carried out at a temperature between 10°C and 95°C, advantageously between 50°C and 75°C. Process according to any one of claims 1 to 8, characterized in that the Fenton catalyst is a source of iron and in that the addition step is carried out on a filtrate having an initial pH of between 2 and 5, advantageously between 2.5 and 4. Process according to any one of claims 1 to 9, characterized in that the filtrate is obtained after a purification step by precipitation of Al/Fe, in particular with lime. Method according to any one of claims 1 to 10, characterized in that the lithium-ion batteries comprise Lithium-Iron-Phosphate type batteries or Lithium-Iron-Phosphate/Lithium-Titanium-Oxide type batteries. Method according to any one of claims 1 to 11, characterized in that the black mass comes from used lithium-ion batteries and/or lithium-ion battery production scrap.