Method for producing regenerated material

Abstract

The present disclosure relates to a method for manufacturing a regenerated material capable of effectively utilizing carbon contained in a battery material. The method for producing a recycled material includes the following steps (a) and (b). Step (a): preparing a battery material. Step (b): carbon disulfide is generated by reacting carbon and sulfur contained in the battery material.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a manufacturing method of a regenerated material. BACKGROUND

[0002] Japanese Patent Application Publication No. 2022-147471 discloses a method of recovering metal from an electrode plate. SUMMARY

[0003] Regeneration of resources is required by recovering various materials from batteries and the like that become unnecessary. In the past, various proposals have been made for a method of recovering and a method of reusing metals. However, there is room for research on a method of recovering and a method of reusing carbon.

[0004] An object of the present disclosure is to provide a method of effectively utilizing carbon contained in a battery material.

[0005] 1. A manufacturing method of a regenerated material, comprising the following process (a) and process (b).

[0006] Process (a): preparing a battery material.

[0007] Process (b): generating carbon disulfide by reacting carbon and sulfur contained in the battery material.

[0008] In the present disclosure, carbon is recovered from a battery material simply, and carbon can be effectively utilized. That is, in the present disclosure, carbon disulfide (CS2) is manufactured from a battery material containing carbon. CS2 is a regenerated material. CS2 can become a raw material for various chemical products. For example, viscose rayon, cellophane, carbon tetrachloride, and the like can be manufactured using CS2 as a raw material.

[0009] 2. The manufacturing method of a regenerated material according to "1" described above may, for example, further include the following. The battery material contains at least one selected from the group consisting of a positive electrode plate, a negative electrode plate, a bipolar electrode plate, a positive electrode mixture, a negative electrode mixture, a black mass, and sludge.

[0010] The battery material is arbitrary as long as it contains carbon. As a component containing carbon, for example, a conductive material in an electrode mixture, a binder, a carbon-based negative electrode active material, and the like can be considered.

[0011] 3. The manufacturing method of a regenerated material according to "1" or "2" described above may, for example, further include the following. The above process (a) includes the following step (al).

[0012] Step (al): forming a powder particle by crushing the battery material.

[0013] By crushing the battery material, for example, an increase in contact efficiency of carbon and sulfur can be expected.

[0014] 4. The method for manufacturing a recycled material according to any one of the above "1" to "3" may, for example, include the following. The above process (a) includes the following step (a2).

[0015] Step (a2): carbonizing the organic matter contained in the battery material by heating the battery material.

[0016] By pre-carbonizing the organic matter (e.g., binder, etc.), an increase in the yield of CS2 can be expected.

[0017] 5. The method for manufacturing a recycled material according to any one of the above "1" to "4" may, for example, include the following. The above process (b) includes bringing sulfur vapor into contact with the battery material.

[0018] By using sulfur vapor, for example, an increase in the contact efficiency of carbon and sulfur can be expected.

[0019] Hereinafter, an embodiment of the present disclosure (hereinafter, can be referred to simply as "the present embodiment") will be described. However, the present embodiment does not limit the technical scope of the present disclosure. The present embodiment is illustrative in all respects. The present embodiment is non-limiting. The technical scope of the present disclosure includes all modifications equivalent to the recitations of the claims and within the scope thereof. For example, a scheme in which any structures are extracted from the present embodiment and combined arbitrarily is anticipated from the beginning. BRIEF DESCRIPTION OF DRAWINGS

[0020] Hereinafter, features, advantages, and technical and industrial significance of exemplary embodiments of the present application will be described with reference to the accompanying drawings, in which like numerals indicate like elements.

[0021] Figure 1 is a schematic flowchart showing the method for manufacturing a recycled material of the present embodiment.

[0022] Figure 2 is a schematic cross-sectional view showing an example of the positive electrode plate of the present embodiment.

[0023] Figure 3 is a schematic cross-sectional view showing an example of the negative electrode plate of the present embodiment.

[0024] Figure 4 is a schematic cross-sectional view showing an example of the bipolar electrode plate of the present embodiment.

[0025] Figure 5 is a conceptual view showing an example of the manufacturing apparatus of the present embodiment. DETAILED DESCRIPTION

[0026] TERMS AND PHRASES

[0027] "possess," "include," "have," and variations thereof are open-ended expressions that are intended to encompass the possibility that an element can be included, but does not necessarily have to be present. By use of open-ended language such as "possess," "include," "have," and "contain," the specification is intended to convey that the described element is an optional element, such that the described element can or can not be present.

[0028] The order of execution of the steps, acts, or operations contained in the various methods is not essential unless specifically stated. For example, the steps, acts, or operations can be performed simultaneously or in an order different from that which is described.

[0029] "battery material" means any material, member, or component included in a battery. The battery material can be a single body or a mixture (e.g., a mixture or the like). The battery material can be, for example, a composite (e.g., an electrode plate or the like), a molded body, or the like.

[0030] "black mass" means a concentrate obtained by, for example, heat treatment (calcination) of a battery, crushing of a calcination product, and sieving of a crushed product. The black mass contains, for example, metals such as nickel, cobalt, and manganese. The metals such as nickel can be, for example, components from a positive electrode active material.

[0031] "sludge" means a residue after valuable metals such as nickel, cobalt, and manganese are extracted from a black mass. In the past, the sludge was discarded. In the present embodiment, the sludge can be effectively utilized as a carbon recovery target.

[0032] Method for manufacturing recycled material

[0033] Figure 1 is a schematic flowchart of a method for manufacturing a recycled material of the present embodiment. Hereinafter, the "method for manufacturing a recycled material of the present embodiment" can be simply referred to as "the present method." The present method includes "step (a) preparation" and "step (b) sulfidation." In the present method, CS2 is manufactured. The CS2 is a recycled material. The present method can further include "step (c) recycling" or the like. In "step (c) recycling," for example, other recycled materials can be manufactured using the CS2 as a raw material.

[0034] Step (a) Preparation

[0035] The present method includes preparation of a battery material. The battery material is arbitrary as long as it is a material containing carbon. The battery material can include, for example, at least one selected from the group consisting of a positive electrode plate, a negative electrode plate, a bipolar electrode plate, a positive electrode mixture, a negative electrode mixture, a black mass, and a sludge. The battery material can be prepared by an arbitrary method. For example, various battery materials can be recovered by disassembling used batteries, defective batteries, or the like. For example, a battery material not containing carbon and a battery material containing carbon can be separated. For the battery material not containing carbon, other recycling processes can be applied. For example, a black mass, a sludge, or the like can be formed by performing various treatments such as calcination on used batteries, defective batteries, or the like.

[0036] Figure 2 This is a schematic cross-sectional view showing an example of the positive electrode plate of this embodiment. The positive electrode plate 10 includes a positive electrode current collector foil 11 and a positive electrode binder 12. The positive electrode current collector foil 11 may, for example, contain aluminum. The positive electrode binder 12 is attached to the positive electrode current collector foil 11. The positive electrode binder 12 may, for example, contain a positive electrode active material, a conductive material, and a binder. The positive electrode active material may, for example, contain lithium nickel composite oxide, olivine phosphate compound, etc. The conductive material may, for example, contain graphite, carbon black, carbon fiber, carbon nanotube, graphene sheet, etc. The binder may, for example, contain polyvinylidene fluoride, etc.

[0037] Figure 3 This is a schematic cross-sectional view showing an example of the negative electrode plate of this embodiment. The negative electrode plate 20 includes a negative electrode current collector foil 21 and a negative electrode binder 22. The negative electrode current collector foil 21 may also include, for example, copper. The negative electrode binder 22 is attached to the negative electrode current collector foil 21. The negative electrode binder 22 may include, for example, a negative electrode active material, a conductive material, and a binder. The negative electrode active material may also include, for example, graphite, soft carbon, hard carbon, silicon, silicon oxide, silicon-carbon composite materials (Si / C materials), lithium titanium composite oxides, etc. The conductive material is the same as that of the positive electrode binder 12. The binder may also include, for example, carboxymethyl cellulose, styrene-butadiene rubber, etc.

[0038] Figure 4 This is a schematic cross-sectional view showing an example of the bipolar electrode plate of this embodiment. The bipolar electrode plate 30 includes a positive electrode compound 12, a positive electrode current collector foil 11, a negative electrode current collector foil 21, and a negative electrode compound 22. For example, an adhesive (not shown) can be used to bond the positive electrode current collector foil 11 and the negative electrode current collector foil 21. The positive electrode compound 12 and the negative electrode compound 22 are in an anti-reverse relationship. Typically, the regeneration process of the bipolar electrode plate 30 begins with the separation of the positive electrode compound 12 and the negative electrode compound 22. During separation, contamination may occur from the negative electrode compound 22 to the positive electrode compound 12. Therefore, for example, when using carbon-based negative electrode active materials (graphite, etc.), there is a tendency for a large amount of carbon waste. This method is particularly effective for the bipolar electrode plate 30.

[0039] In the positive electrode plate 10, negative electrode plate 20, and bipolar electrode plate 30, the main targets for carbon recovery are conductive materials (such as carbon black), binders (organic polymers), and carbon-based negative electrode active materials (such as graphite, soft carbon, hard carbon, and Si / C materials). For example, sometimes conductive materials (such as carbon black) are coated on the surface of the positive electrode current collector foil 11. The conductive material coated on the positive electrode current collector foil 11 can also be a target for carbon recovery.

[0040] Step (a1) Crushing

[0041] This method may also include, for example, forming powder particles by crushing battery materials. The battery materials can be crushed using any crushing device. Crushing the battery materials can, for example, improve processability. Furthermore, in the "step (b) sulfidation" described later, improved contact efficiency between carbon and sulfur can also be expected. For example, the positive electrode compound 12 can be crushed after being peeled from the positive electrode current collector foil 11. For example, the positive electrode plate 10 can also be crushed directly.

[0042] Step (a2) Carbonization

[0043] This method may also involve carbonizing the organic matter contained in the battery material by heating it. For example, the crushed powder can also be heated. Any heating device can be used. For example, the battery material can be heated at a temperature above 300°C. By heating, the organic matter (e.g., binder, etc.) is expected to be carbonized. By pre-carbonizing the organic matter, the yield of CS2 can be expected to increase in the "step (b) sulfidation" described later. The carbonization temperature (heating temperature) can, for example, be above 450°C or above 600°C. The carbonization temperature can, for example, be below 900°C, below 750°C, or below 600°C. The carbonization atmosphere can, for example, be an air atmosphere, a low-oxygen atmosphere, an oxygen-free atmosphere, etc.

[0044] Process (b) Vulcanization

[0045] This method involves reacting the carbon (C) and sulfur (S) contained in the battery material to generate CS2. Figure 5 This is a conceptual diagram illustrating an example of the manufacturing apparatus of this embodiment. The manufacturing apparatus 100 may, for example, include a heating furnace 101, a recovery piping 102, a cooling tower 103, a recovery container 104, a gas inlet pipe 105, etc. For example, a workpiece 50 is disposed within the heating furnace 101. The workpiece 50 may, for example, be a mixture of battery material and sulfur powder (solid). The workpiece 50 is heated within the heating furnace 101. For example, the temperature may be raised to 850–950°C. During the heating process, since the boiling point of sulfur (444.6°C) is exceeded, sulfur powder can generate sulfur vapor. As the sulfur vapor permeates into the battery material, sulfur and carbon can come into contact. That is, this method includes contacting sulfur vapor with the battery material. It is assumed that when the battery material is a powder (fragmented material), the permeation of sulfur vapor proceeds smoothly. In the temperature range of 850–950°C, CS2 can be generated by the reaction "C + 2S → CS2". Since the environment inside the heating furnace 101 is above the boiling point of CS2 (46.5°C), CS2 can be generated in a gaseous state.

[0046] The manufacturing apparatus 100 may also include, for example, a stirring device (not shown). For example, the workpiece 50 may be stirred within the heating furnace 101. By stirring the workpiece 50, it is expected that the contact efficiency between sulfur and carbon will be improved.

[0047] The generated CS2 (gas) can reach the cooling tower 103 through the recovery piping 102. In the cooling tower 103, the CS2 can be liquefied by cooling it below its boiling point. The CS2 (liquid) can be recovered by the recovery container 104.

[0048] For example, sulfur vapor can be used instead of sulfur powder (solid). For example, sulfur vapor can also be blown onto the heated workpiece 50. For example, sulfur vapor can also be supplied to the heating furnace 101 through the gas inlet pipe 105.

[0049] For example, the positive electrode plate 10, the negative electrode plate 20, and the bipolar electrode plate 30 can also be used as workpieces 50. For example, in the heating furnace 101, sulfur vapor can be blown onto the positive electrode plate 10 (an integral part of the positive electrode mixture 12 and the positive electrode current collector foil 11). According to this method, while CS2 is generated, the positive electrode mixture 12 loses its adhesion and can be separated from the positive electrode current collector foil 11.

[0050] The processed residue is a carbon-reduced battery material. Further recycling processes (such as metal extraction) can be applied to the residue.

[0051] Process (c) Regeneration

[0052] CS2 is a recycled material. Various materials can be manufactured using CS2 as a raw material. For example, CS2 can also be used to manufacture viscose rayon, cellophane, carbon tetrachloride, etc.

[0053] CS2 can also be used as a solvent. For example, it can be used as a solvent for phosphorus, sulfur, selenium, bromine, iodine, lipids, resins, rubber, etc.

[0054] For example, lithium sulfide (Li2S) can also be manufactured using CS2 as a raw material. Lithium sulfide can serve as a raw material for sulfide solid electrolytes (such as Li2S-P2S5, etc.). Sulfide solid electrolytes are key materials for all-solid-state batteries. For example, lithium sulfide can also be synthesized through the reaction "4LiH + CS2 → 2Li2S + C + 2H2" or "4Li + CS2 → 2Li2S + C".

[0055] For example, carbonyl sulfide (COS) can also be produced using CS2 as a raw material. Carbonyl sulfide can be used as an etching gas in semiconductor manufacturing processes. Alternatively, carbonyl sulfide can be synthesized via the reaction "CO2 + CS2 → 2COS". As shown in the reaction equation, carbon dioxide is consumed during the formation of carbonyl sulfide, thus contributing to carbon neutralization.

[0056] Furthermore, carbon monoxide can also be produced, for example, through the contact decomposition reaction of carbonyl sulfide "COS→CO+S". Carbon monoxide can be used as a feedstock in various fuels and the chemical industry. Moreover, the sulfur generated along with carbon monoxide can be reused for carbon recovery.

Claims

1. A method for manufacturing a recycled material, comprising: Process (a): Preparing battery materials; and Step (b): Carbon disulfide is generated by reacting the carbon and sulfur contained in the battery material.

2. The method for manufacturing recycled materials according to claim 1, The battery material comprises at least one selected from positive electrode plate, negative electrode plate, bipolar electrode plate, positive electrode mixture, negative electrode mixture, black matter and sludge.

3. The method for manufacturing recycled materials according to claim 1, The process (a) includes step (a1): The battery material is broken down to form powder particles.

4. The method for manufacturing recycled materials according to claim 1, The process (a) includes step (a2): The organic matter contained in the battery material is carbonized by heating the battery material.

5. The method for manufacturing recycled materials according to any one of claims 1 to 4, The process (b) includes: contacting sulfur vapor with the battery material.

Images