CN116154117A - A kind of preparation method of positive electrode material of water system zinc ion battery - Google Patents

Abstract

The invention discloses a preparation method of a water-based zinc ion battery anode material, which comprises the following steps: coating a conductive polymer on the surface of an anode active material by a gas phase polymerization or liquid phase polymerization method to obtain an anode material of the water-based zinc ion battery; wherein, the conductive polymer formed on the surface of the positive electrode material of the water-based zinc ion battery is ordered; the positive electrode active material is; graphene, manganese-based oxides, vanadium-based nitroxides, prussian blue and analogs thereof, metal/covalent organic framework compounds, organic electro-chemical materials, layered MXene, layered sulfides, and layered selenides. The water-based zinc ion battery anode material prepared by the method overcomes the problem of dissolution of active materials in the existing anode material, realizes high-efficiency utilization of the anode active material, enhances storage of zinc ions, and further improves the rate performance and the cycle stability of the battery.

Description

A kind of preparation method of positive electrode material of water system zinc ion battery

technical field

The invention relates to the field of electrochemical energy storage devices, in particular to a method for preparing a positive electrode material of an aqueous zinc-ion battery.

Background technique

As a high-efficiency energy storage device, secondary batteries are widely used in fields such as mobile phone communications and electric vehicles. At present, the most widely used secondary battery in commercial use is lithium-ion battery, but due to the high cost of lithium resources, low safety and supply risks, it is not suitable for large-scale power grid energy technology. Zn-based batteries are a good alternative to Li-ion batteries due to their higher capacity (two-electron reaction), lower cost, and more moderate redox potential ( -0.762V vs. H/H ⁺ ). Therefore, developing rechargeable Zn-ion batteries has become an urgent yet attractive task today.

Aqueous Zn-ion batteries based on water-based electrolytes are considered to be one of the most promising energy storage technologies due to their high safety, low cost, and excellent electrochemical performance. But at present, the development of aqueous zinc-ion batteries is still in its infancy. Among them, the positive electrode materials play a decisive role in the study of zinc storage mechanism and the construction of high-performance batteries. At present, the common positive electrode materials include manganese-based oxides, vanadium-based oxides compounds, vanadium-based oxynitrides, Prussian blue and its analogues, metal/covalent organic framework compounds, layered MXene and layered sulfides, selenides, etc. However, these positive electrode materials are all faced with the problem that the active material is easily dissolved, and the dissolution of the active material brings about a decrease in the storage of zinc ions and a decrease in the cycle stability of the battery system. Therefore, it is an urgent problem to provide a structurally stable cathode material for aqueous zinc-ion batteries.

Contents of the invention

The object of the present invention is to provide a method for preparing the positive electrode material of an aqueous zinc ion battery.

To achieve the above object, the present invention adopts the following technical solutions:

The invention provides a method for preparing a positive electrode material of a water-based zinc-ion battery. The method comprises: coating a conductive polymer on the surface of a positive-electrode active material by gas-phase polymerization or liquid-phase polymerization to obtain the positive-electrode material of a water-based zinc-ion battery;

Among them, the conductive polymer formed on the surface of the positive electrode material of the aqueous zinc ion battery is ordered;

The positive electrode active material is: graphene, manganese-based oxides, vanadium-based oxides, vanadium-based oxynitrides, Prussian blue and the like, metal/covalent organic framework compounds, organic electrochemical materials, layered MXene, One or more of layered sulfides and layered selenides.

It should be noted that, generally speaking, the growth of polymers is disordered, intertwined and interpenetrated, and the preparation method of the present invention utilizes the two-dimensional and microcavity structure of the positive electrode active material to regulate the polymerization process of the polymer, The growth of the polymer is oriented and ordered, that is, the polymer grows layer by layer along the surface of the positive electrode active material in an orderly manner and forms a coating. For example, when polypyrrole grows layer by layer in an orderly manner along the surface of the positive electrode active material, the five-membered rings of the pyrrole monomers are connected one by one and in an orderly arrangement (as shown in FIG. 1 ). In addition, it is well known that the positive electrode materials of traditional water-based zinc-ion batteries generally have the problems of easy dissolution of active materials and low utilization. The ordered framework structure of the polymer improves the structural stability of the positive electrode active material to enhance the storage of zinc ions and improve the rate performance and cycle stability of the battery.

Preferably, the manganese-based oxides mainly include manganese oxides of tetravalent, trivalent and intermediate valence states according to the valence state of manganese, more preferably, manganese dioxide, trimanganese tetraoxide and dimanganese trioxide; The general chemical formula of Prussian blue and its analogues is MFe(CN) ₆ (M=Fe, Co, Ni, Cu, Mn), such as CuFe(CN) ₆ (CuHCF), Zn ₃ [Fe(CN) ₆ ] ₂ (ZnHCF), etc.; the organic electrochemical materials include conductive polymers such as polypyrrole, polyaniline, etc.

Further, the conductive polymer includes one or more of polypyrrole, polythiophene, polyaniline, poly-3,4-ethylenedioxythiophene and poly-3-hexylthiophene.

Further, the gas phase polymerization specifically includes the following steps:

Form the dispersion liquid of positive electrode active material, optionally add oxidizing agent and/or conductive agent into the dispersion liquid, dry, and then place in a closed container containing gaseous conductive polymer monomer to carry out in-situ polymerization reaction, then .

Wherein, the above-mentioned preparation method may include an oxidizing agent, and those skilled in the art know that the positive electrode active material has oxidizing properties according to different types of selection, so those skilled in the art can add additional oxidizing agents or only use the positive electrode active material as required. Own oxidizing properties for in situ polymerization. In addition, the above-mentioned preparation method may also include a conductive agent, which is commonly used as a carbon-based conductive agent. Those skilled in the art know how to select the most suitable ones for aqueous zinc-ion batteries from various conductive agents, such as conductive carbon black and acetylene black. (AB), 350G, etc.

Further, in the dispersion liquid, the concentration of the positive electrode active material is 0.01-15 mg/mL.

Further, the addition amount of the oxidizing agent is 0.0005-0.1 mol/L. Among them, the present invention finds that the concentration of the oxidizing agent and the concentration of the positive electrode active material affect the rate of the polymerization reaction, and only within a specific reaction rate range, the order degree of the synthesized conductive polymer will be higher. Therefore, no matter whether the oxidizing properties of the positive electrode active material are utilized or not, the amount of the oxidizing agent that can be added can better control the order degree of the conductive polymer only within the scope of the present invention.

According to a specific embodiment of the present invention, the drying includes, but is not limited to, heat drying, blast drying, freeze drying, and room temperature drying, and is preferably freeze drying.

Further, the conditions of the in-situ polymerization reaction are as follows: the temperature of the in-situ polymerization reaction is -30-40° C., and the time of the in-situ polymerization reaction is 1 hour to 50 days. Wherein, the temperature of the in-situ polymerization reaction is within the scope of the present invention, which can ensure the gaseous state of the conductive polymer monomer and control the rate of the in-situ polymerization reaction.

Further, the oxidizing agent includes one or more of ferric chloride, ammonium persulfate, aluminum chloride, molybdenum trichloride, ruthenium trichloride, peracetic acid, hydrogen peroxide and potassium permanganate.

Further, the liquid phase polymerization specifically includes the following steps:

Form a dispersion liquid of the positive active material, optionally add an oxidizing agent and/or a conductive agent into the dispersion liquid, and then add a conductive polymer monomer to carry out in-situ polymerization reaction.

Further, in the dispersion liquid, the concentration of the positive electrode active material is 0.03-20 mg/mL.

Further, the addition amount of the oxidizing agent is 0.00001-0.005 mol/L.

Further, the oxidizing agent includes one or more of ferric chloride, ammonium persulfate, aluminum chloride, molybdenum trichloride, ruthenium trichloride, peracetic acid, hydrogen peroxide and potassium permanganate.

Further, the conditions of the in-situ polymerization reaction are as follows: the temperature of the in-situ polymerization reaction is 0-25° C., and the time of the in-situ polymerization reaction is 0.5 hours to 50 days.

Among them, the preparation of ordered conductive polymers by liquid-phase polymerization is more difficult to control than gas-phase polymerization. Because the wide dispersion of gaseous polymer monomers is more conducive to slow layer-by-layer growth, while the polymerization speed of liquid monomers is faster, so it is necessary to control the details of the conditions in the reaction process to successfully synthesize orderly conductive polymers. . Therefore, if the various conditions of the liquid phase polymerization are not within the scope of the present invention, the order degree of the final conductive polymer is poor, or even completely disordered.

In addition, unless otherwise specified, any range described in the present invention includes any sub-range formed by the end value or any value between the end values and any value between the end value or any value between the end values. All the raw materials in the present invention have no special limitation on their purity, and the present invention preferably adopts analytical purity. All the raw materials of the present invention, their sources and abbreviations belong to conventional sources and abbreviations in the field, and are clear and definite in the field of their related uses. Those skilled in the art can buy them from the market or obtain them according to the abbreviations and corresponding uses. Prepared by conventional methods. All percentages in the present invention are mass percentages unless otherwise specified, and the solution uses water as a solvent unless otherwise specified.

The beneficial effects of the present invention are as follows:

The positive electrode material prepared by the preparation method provided by the invention overcomes the problem that the active components in the positive electrode material of the existing aqueous zinc ion battery are easily soluble, improves the structural stability of the positive electrode material of the traditional aqueous zinc ion battery, and realizes the high efficiency of the positive electrode material Utilization, and then improve the storage of zinc ions, rate performance and cycle stability of aqueous zinc ion batteries.

The preparation method of the positive electrode material of the water-based zinc ion battery provided by the invention has cheap and easy-to-obtain raw materials, simple process and convenient operation, and is suitable for large-scale production and application.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained based on these drawings without creative effort.

Figure 1 shows a schematic diagram of the molecular structure of ordered polypyrrole.

Fig. 2 shows the selected area electron diffraction pattern of the positive electrode material of the aqueous zinc ion battery prepared in Example 1.

FIG. 3 shows the cycle performance test chart of the aqueous zinc-ion battery in Example 1.

FIG. 4 shows the cycle performance test chart of the aqueous zinc-ion battery in Comparative Example 1.

Detailed ways

In order to illustrate the present invention more clearly, the present invention will be further described below in conjunction with preferred embodiments and accompanying drawings. Similar parts in the figures are denoted by the same reference numerals. Those skilled in the art should understand that the content specifically described below is illustrative rather than restrictive, and should not limit the protection scope of the present invention.

Example 1

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

Graphene oxide aqueous dispersion (3 mg/mL) containing 0.005M ferric chloride (FeCl ₃ ) was ultrasonically dispersed for 2 hours to obtain a mixed solution, and then the mixed solution was poured into a petri dish and placed in a refrigerator (-70°C) for 2 hours to freeze , followed by freeze-drying at -60 °C for 40 h to obtain graphene oxide foam (GOF). Put the prepared GOF in an airtight container with pyrrole monomer vapor. At 10°C, pyrrole was polymerized in situ on the GOF (gas phase polymerization) for 1.5 hours. Under the lower reduction, the positive electrode material-ordered polypyrrole-coated graphene foam was obtained.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is a zinc sheet, and the positive electrode material is the graphene foam coated with ordered polypyrrole prepared in this embodiment. After first grinding the graphene foam coated with ordered polypyrrole, press positive electrode material/carbon black/PVDF= The mass ratio of 70/20/10 is slurried, coated on graphite paper, and dried to make electrodes. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: the water system zinc ion button battery of the present embodiment is charged and discharged at 1-1.8V, and the current density is 1A/g, and it is cycled 1200 times at room temperature, and the capacity retention rate is 80% (the result is shown in Fig. 3).

It can be seen from Figure 2 that the selected area electron diffraction pattern of the ordered polypyrrole-coated graphene foam prepared in this example has obvious polycrystalline characteristics, thus illustrating the orderliness of the polypyrrole chain.

Example 2

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

After ultrasonic dispersion of MXene aqueous dispersion (0.034mg/mL) containing 0.00025M ammonium persulfate for 2h, at 16°C, add an appropriate amount of aniline monomer (the molar ratio of oxidant to monomer is 2:1), and then magnetically stir After 1.5 h, the solution was collected, frozen in a refrigerator (-70 °C) for 2 h, and then freeze-dried at -60 °C for 40 h to obtain the positive electrode material-ordered polyaniline-coated MXene.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is zinc flakes, and the positive electrode material is ordered polyaniline-coated MXene. Firstly, after grinding the ordered polyaniline-coated MXene, it is adjusted according to the mass ratio of positive electrode material/carbon black/PVDF=70/20/10. slurry, coated on graphite paper, and dried to form an electrode. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: The water-based zinc-ion button battery of this embodiment was charged and discharged at 1-1.8V, with a current density of 1A/g, 1200 cycles at room temperature, and a capacity retention rate of 82%.

Example 3

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

Manganese dioxide aqueous dispersion containing 0.00001M potassium permanganate (0.034mg/mL) 0 After ultrasonic dispersion for 2 hours, add an appropriate amount of thiophene monomer at 20°C (the molar ratio of oxidant to monomer is 2:1) , and then magnetically stirred for 1.5h, the solution was collected, placed in a refrigerator (-70°C) for 2h, and then freeze-dried at -60°C for 40h to obtain the positive electrode material-ordered polythiophene-coated manganese dioxide.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is zinc sheet, and the positive electrode material is manganese dioxide coated with ordered polyaniline. Firstly, after grinding the ordered polyaniline coated manganese dioxide, the mass of positive electrode material/carbon black/PVDF=70/20/10 Slurry is prepared, coated on graphite paper, and dried to make electrodes. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: The water-based zinc-ion button battery of this embodiment was charged and discharged at 1-1.8V, with a current density of 1A/g, 1200 cycles at room temperature, and a capacity retention rate of 78%.

Example 4

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

Graphene oxide aqueous dispersion (3mg/mL) containing 0.0005M ferric chloride (FeCl ₃ ) was ultrasonically dispersed for 2 hours to obtain a mixed solution, and then the mixed solution was poured into a petri dish and placed in a refrigerator (-70°C) for 2 hours to freeze , followed by freeze-drying at -60 °C for 40 h to obtain graphene oxide foam (GOF). The prepared GOF was placed in a closed container with aniline monomer vapor, and the aniline was in-situ polymerized on the GOF for 3 hours at 0°C, then taken out, and then reduced with hydrazine hydrate at 80°C in a vacuum environment to obtain the positive electrode material- Graphene foam wrapped in ordered polyaniline.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is a zinc sheet, and the positive electrode material is the graphene foam coated with ordered polyaniline prepared in this embodiment. After first grinding the graphene foam coated with ordered polyaniline, press positive electrode material/carbon black/PVDF= The mass ratio of 70/20/10 is slurried, coated on graphite paper, and dried to make electrodes. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: The water-based zinc-ion button battery of this embodiment was charged and discharged at 1-1.8V, with a current density of 1A/g, 1200 cycles at room temperature, and a capacity retention rate of 79%.

Example 5

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

MXene aqueous dispersion (0.034mg/mL) containing 0.00025M ammonium persulfate was ultrasonically dispersed for 2h, then an appropriate amount of thiophene monomer was added (the molar ratio of oxidant to monomer was 2:1), and then magnetically stirred at 15°C for 1h, and collected The solution was frozen in a refrigerator (-70°C) for 2h, and then freeze-dried at -60°C for 40h to obtain the positive electrode material-ordered polythiophene-coated MXene.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is zinc flakes, and the positive electrode material is MXene coated with ordered polythiophene. Firstly, after grinding the MXene coated with ordered polythiophene, it is adjusted according to the mass ratio of positive electrode material/carbon black/PVDF=70/20/10. slurry, coated on graphite paper, and dried to form an electrode. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: The water-based zinc-ion button battery of this embodiment was charged and discharged at 1-1.8V, and the current density was 1A/g, and it was cycled 1200 times at room temperature, and the capacity retention rate was 76%.

Example 6

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

Manganese dioxide aqueous dispersion (0.034mg/mL) containing 0.00001M ammonium persulfate was ultrasonically dispersed for 2h, then an appropriate amount of thiophene monomer was added (the molar ratio of oxidant to monomer was 2:1), and then magnetically stirred at 15°C for 1.5h Finally, the solution was collected, placed in a refrigerator (-70°C) for 2 hours, and then freeze-dried at -60°C for 40 hours to obtain the positive electrode material-ordered polythiophene-coated manganese dioxide.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is zinc sheet, and the positive electrode material is manganese dioxide coated with ordered polyaniline. Firstly, after grinding the ordered polyaniline coated manganese dioxide, the mass of positive electrode material/carbon black/PVDF=70/20/10 Slurry is prepared, coated on graphite paper, and dried to make electrodes. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: The water-based zinc-ion button battery of this embodiment was charged and discharged at 1-1.8V, with a current density of 1A/g, 1200 cycles at room temperature, and a capacity retention rate of 73%.

Example 7

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

Graphene oxide aqueous dispersion (3mg/mL) containing 0.0005M ferric chloride was ultrasonically dispersed for 2 hours to obtain a mixed solution, then poured the mixed solution into a petri dish and put it in a refrigerator (-70°C) for 2 hours, then placed it in - Freeze-dry at 60°C for 40 hours to obtain graphene oxide foam (GOF). Put the prepared GOF in a closed container with 3,4-ethylenedioxythiophene monomer vapor, and in situ polymerization (gas phase polymerization) of 3,4-ethylenedioxythiophene on the GOF at 0°C for 2 hours, then take it out , in a vacuum environment, reduced with hydrazine hydrate at 80 ° C to obtain the positive electrode material - graphene foam coated with ordered poly-3,4-ethylenedioxythiophene.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is a zinc sheet, and the positive electrode material is the graphene foam coated with ordered poly-3,4-ethylenedioxythiophene prepared in this example. First, the ordered poly-3,4-ethylenedioxythiophene-coated graphite After the olefin foam is ground, it is slurried according to the mass ratio of positive electrode material/carbon black/PVDF=70/20/10, and it is coated on graphite paper and dried to make an electrode. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: The water-based zinc-ion button battery of this embodiment was charged and discharged at 1-1.8V, and the current density was 1A/g, 1200 cycles at room temperature, and the capacity retention rate was 81%.

Example 8

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

The oxidized MXene aqueous dispersion (5mg/mL) containing 0.001M ferric chloride was ultrasonically dispersed for 2 hours to obtain a mixed solution, and then the mixed solution was poured into a petri dish and frozen in a refrigerator (-70°C) for 2 hours, then at -60 Freeze-dry at ℃ for 40 h to obtain MXene foam. Put the prepared MXene foam in a closed container with 3,4-ethylenedioxythiophene monomer vapor, and in situ polymerization (gas phase polymerization) of 3,4-ethylenedioxythiophene on the MXene foam at 0°C for 2 hours After taking it out, the positive electrode material-ordered poly-3,4-ethylenedioxythiophene-coated MXene foam is obtained.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is zinc flakes, and the positive electrode material is the ordered poly-3,4-ethylenedioxythiophene-coated MXene foam prepared in this example. First, the ordered poly-3,4-ethylenedioxythiophene-coated MXene foam After the foam is ground, the slurry is adjusted according to the mass ratio of positive electrode material/carbon black/PVDF=70/20/10, and it is coated on graphite paper and dried to make an electrode. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: The water-based zinc-ion button battery of this embodiment was charged and discharged at 1-1.8V, and the current density was 1A/g, and it was cycled 1200 times at room temperature, and the capacity retention rate was 72%.

Example 9

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

Manganese dioxide aqueous dispersion (0.1mg/mL) containing 0.00005M ammonium persulfate was ultrasonically dispersed for 2h, then an appropriate amount of thiophene monomer was added (the molar ratio of oxidant to monomer was 2:1), and then magnetically stirred at 15°C for 1.5h Finally, the solution was collected, placed in a refrigerator (-70°C) for 2 hours, and then freeze-dried at -60°C for 40 hours to obtain the positive electrode material-ordered polythiophene-coated manganese dioxide.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is zinc sheet, and the positive electrode material is manganese dioxide coated with ordered polyaniline. Firstly, after grinding the ordered polyaniline coated manganese dioxide, the mass of positive electrode material/carbon black/PVDF=70/20/10 Slurry is prepared, coated on graphite paper, and dried to make electrodes. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: The water-based zinc-ion button battery of this embodiment was charged and discharged at 1-1.8V, and the current density was 1A/g, and it was cycled 1200 times at room temperature, and the capacity retention rate was 70%.

Example 10

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

The oxidized MXene aqueous dispersion (20mg/mL) containing 0.005M ferric chloride was ultrasonically dispersed for 2 hours to obtain a mixed solution, and then the mixed solution was poured into a petri dish and frozen in a refrigerator (-70°C) for 2 hours, and then placed at -60 Freeze-dry at ℃ for 40 h to obtain MXene foam. Put the prepared MXene foam in a closed container with 3,4-ethylenedioxythiophene monomer vapor, and in situ polymerization (gas phase polymerization) of 3,4-ethylenedioxythiophene on the MXene foam at 0°C for 1.5 After h, it was taken out to obtain the positive electrode material-ordered poly-3,4-ethylenedioxythiophene-coated MXene foam.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is zinc flakes, and the positive electrode material is the ordered poly-3,4-ethylenedioxythiophene-coated MXene foam prepared in this example. First, the ordered poly-3,4-ethylenedioxythiophene-coated MXene foam After the foam is ground, the slurry is adjusted according to the mass ratio of positive electrode material/carbon black/PVDF=70/20/10, and it is coated on graphite paper and dried to make an electrode. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: The water-based zinc-ion button battery of this embodiment was charged and discharged at 1-1.8V, with a current density of 1A/g, 1200 cycles at room temperature, and a capacity retention rate of 71%.

Comparative example 1

1) prepare a kind of positive electrode material of water system zinc ion battery, comprise the steps:

Graphene oxide aqueous dispersion (3 mg/mL) containing 0.1M ferric chloride (FeCl ₃ ) was ultrasonically dispersed for 2 hours, then 1 mL of pyrrole monomer was added, ultrasonically dispersed for 30 minutes, and after standing for 24 hours, the mixture was poured out after the reaction was complete. into the petri dish. The petri dish was frozen in a refrigerator (-70°C) for 2 hours, and then freeze-dried at -60°C for 40 hours to obtain a disordered polypyrrole-coated graphene oxide foam. Then, in a vacuum environment, it was reduced with hydrazine hydrate at 80°C to obtain the cathode material - graphene foam coated with disordered polypyrrole.

2) Assemble the water system zinc-ion battery, including the following steps:

The negative electrode material is a zinc sheet, and the positive electrode material is the graphene foam coated with disordered polypyrrole prepared in this embodiment. After first grinding the graphene foam coated with disordered polypyrrole, press positive electrode material/carbon black/PVDF= The mass ratio of 70/20/10 is slurried, coated on graphite paper, and dried to make electrodes. The diaphragm adopts GFF diaphragm, and the electrolyte adopts 2mol/L zinc sulfate + 0.1mol/L manganese sulfate to assemble into a water system zinc ion button battery.

3) Performance test: the water-based zinc ion button battery of the present embodiment was charged and discharged at 1-1.8V, and the current density was 1A/g, 1200 cycles at room temperature, and the capacity retention rate was 41% (the result is shown in Fig. 4).

Apparently, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those of ordinary skill in the art can also make It is not possible to exhaustively list all the embodiments here, and any obvious changes or changes derived from the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims (10)

1. The preparation method of the water-based zinc ion battery anode material is characterized by comprising the following steps of: coating a conductive polymer on the surface of an anode active material by a gas phase polymerization or liquid phase polymerization method to obtain an anode material of the water-based zinc ion battery;

wherein, the conductive polymer formed on the surface of the positive electrode material of the water-based zinc ion battery is ordered;

the positive electrode active material is: graphene, manganese-based oxides, vanadium-based nitroxides, prussian blue and analogs thereof, metal/covalent organic framework compounds, organic electro-chemical materials, layered MXene, layered sulfides, and layered selenides.

2. The method of claim 1, wherein the conductive polymer comprises one or more of polypyrrole, polythiophene, polyaniline, poly 3, 4-ethylenedioxythiophene, and poly 3-hexylthiophene.

3. The preparation method according to any one of claims 1 to 2, characterized in that the gas-phase polymerization comprises in particular the following steps:

forming a dispersion of the positive electrode active material, optionally adding an oxidizing agent and/or a conductive agent to the dispersion, drying, and then placing in a closed container containing a gaseous conductive polymer monomer for in-situ polymerization.

4. The method according to claim 3, wherein the concentration of the positive electrode active material in the dispersion is 0.01 to 15mg/mL;

preferably, the oxidant is added in an amount of 0.0005 to 0.1mol/L.

5. A method according to claim 3, wherein the conditions for the in situ polymerization are: the temperature of the in-situ polymerization reaction is-30-40 ℃, and the time of the in-situ polymerization reaction is 1 hour-50 days.

6. The method of claim 3, wherein the oxidizing agent comprises one or more of ferric chloride, ammonium persulfate, aluminum chloride, molybdenum trichloride, ruthenium trichloride, peracetic acid, hydrogen peroxide, and potassium permanganate.

7. The preparation method according to any one of claims 1 to 2, characterized in that the liquid phase polymerization comprises the following steps:

forming a dispersion of the positive electrode active material, optionally adding an oxidizing agent and/or a conductive agent to the dispersion, and then adding a conductive polymer monomer to perform in-situ polymerization.

8. The production method according to claim 7, wherein the concentration of the positive electrode active material in the dispersion is 0.03 to 20mg/mL;

preferably, the addition amount of the oxidizing agent is 0.00001 to 0.005mol/L.

9. The method of claim 7, wherein the oxidizing agent comprises one or more of ferric chloride, ammonium persulfate, aluminum chloride, molybdenum trichloride, ruthenium trichloride, peracetic acid, hydrogen peroxide, and potassium permanganate.

10. The method of claim 7, wherein the in situ polymerization conditions are: the temperature of the in-situ polymerization reaction is 0-25 ℃, and the time of the in-situ polymerization reaction is 0.5 hours-50 days.

Images