Battery processing method

Abstract

The purpose of the present invention is to improve the recovery efficiency by suppressing the mixing of other metals in a step for recovering a valuable metal including nickel, cobalt, or manganese from a used secondary battery. This battery processing method uses, as a target battery, an all-solid-state battery configured using a copper member, the all-solid-state battery comprising: a positive electrode having a positive electrode composite material containing a positive electrode active material; a negative electrode; and a sulfide-based solid electrolyte. The method for processing a battery comprises: an inactivation step for inactivating the contents of a target battery under conditions that promote a vulcanization reaction of a copper member; a separation step for separating the positive electrode composite material from the material constituting the positive electrode; a treatment step for forming a slurry containing the positive electrode composite material separated in the separation step; a flotation separation step for removing solids from the copper member from the slurry by flotation separation; and a recovery step for recovering the positive electrode active material from the slurry from which the solids have been removed in the flotation step.

Description

Technical Field

[0001] The present invention relates to a battery processing method. Background Art

[0002] In recent years, research and development into the reuse of secondary batteries, which contribute to improving energy efficiency, has been underway to ensure greater access to suitable, reliable, sustainable, and advanced energy. For example, lithium-ion batteries and all-solid-state batteries have stacked electrodes consisting of positive and negative plates sandwiched between separators. The positive electrode composite material of these batteries uses a ternary positive material (NCM) composed of nickel, cobalt, and manganese. Consequently, methods have been proposed for recovering valuable metals, such as NCM, from used secondary batteries.

[0003] For example, Patent Document 1 discloses a method in which a battery component containing a sulfide-based solid electrolyte material is immersed in a treatment liquid containing water to generate hydrogen sulfide and dissolve lithium contained in the sulfide-based solid electrolyte material.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. WO2010 / 106618 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] Secondary batteries use metal materials such as aluminum and copper, for example, copper foil as the negative electrode current collector. These metals can sometimes contaminate the positive electrode materials, which include nickel, cobalt, and manganese, when they are recovered from the secondary batteries. Therefore, to improve the recovery efficiency of the positive electrode materials, it is desirable to prevent the contamination of these metals.

[0009] To address the above-mentioned issues, the present application aims to improve recovery efficiency by suppressing the incorporation of other metals during the recovery process of valuable metals including nickel, cobalt, or manganese from used secondary batteries, thereby contributing to energy efficiency.

[0010] Means for solving problems

[0011] A proposal of the present disclosure relates to a battery processing method, wherein the battery processing method uses an all-solid-state battery composed of a copper component as the target battery, the all-solid-state battery having: a positive electrode having a positive electrode composite material containing a positive electrode active material; a negative electrode; and a sulfide-based solid electrolyte, wherein the battery processing method includes: a deactivation process, in which the contents of the target battery are deactivated under conditions that promote a sulfidation reaction of the copper component; a separation process, in which the positive electrode composite material is separated from a material constituting the positive electrode; a treatment process, in which a slurry containing the positive electrode composite material separated in the separation process is formed; a flotation sorting process, in which solids from the copper component are removed from the slurry by flotation sorting; and a recovery process, in which the positive electrode active material is recovered from the slurry from which the solids have been removed in the flotation sorting process.

[0012] Effects of the Invention

[0013] According to one proposal of the present disclosure, in the process of recovering valuable metals including nickel, cobalt, or manganese from used secondary batteries, the incorporation of metals from copper components of the battery can be suppressed, thereby improving the recovery efficiency of the valuable metals. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 1 is a diagram showing the structure of a target battery as an example of a battery to which the present disclosure is applied.

[0015] Figure 2 This is a diagram showing a method of handling a battery.

[0016] Figure 3 It is a schematic diagram showing a treatment example in the flotation separation step.

[0017] Description of reference numerals:

[0018] 2…Floatation separation system, 3, 3A, 3B, 3C, 3D, 3E, 3F…Separation tank, 10…Target battery, 11…Positive electrode plate, 12…Negative electrode plate, 13…Separator, 21…Laminated electrode, 22…Laminate, 32…Positive electrode composite material, 42…Negative electrode composite material. DETAILED DESCRIPTION

[0019] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0020] [1. Structure of the target battery]

[0021] Figure 1This figure shows the structure of a target battery 10 as an example of a battery to which the present disclosure is applicable, schematically illustrating a cross-section of the target battery 10. The target battery 10 is a secondary battery capable of charge and discharge. The target battery 10 described in this embodiment is a laminated battery in which battery materials are enclosed in a laminate 22, and has an overall flat plate shape. Examples of the target battery 10 include pouch-type batteries, laminated battery cells, pouch-type battery cells, lithium-ion battery cells, and battery modules.

[0022] The target battery 10 is a secondary battery known as a lithium-ion battery, which has attracted attention as a storage device with high energy density. Examples of positive electrode active materials for lithium-ion batteries include lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, and lithium iron phosphate. In addition, examples of positive electrode active materials include ternary positive electrode materials (NCMs) containing nickel, cobalt, and manganese. Examples of negative electrode active materials for lithium-ion batteries include carbon-based materials. Furthermore, all-solid-state batteries using solid electrolytes as the electrolyte for lithium-ion batteries are known.

[0023] Nickel, cobalt, and manganese, used as positive electrode active materials in lithium-ion batteries and all-solid-state batteries, are known as valuable metals and are often recycled from used batteries. Therefore, in this embodiment, a highly efficient treatment method for these metals is disclosed. In the treatment method disclosed herein, the electrode material to be recycled is the valuable metal contained in the target battery 10, more specifically, a compound related to the NCM contained in the positive electrode active material of the positive electrode current collector 31. Specifically, it is a substance containing at least one of nickel, cobalt, and manganese.

[0024] More specifically, the positive electrode active material is a material that can absorb and release Li ions, and examples thereof include layered positive electrode active materials, spinel-type positive electrode active materials, and olivine-type positive electrode active materials. Examples of layered positive electrode active materials include LiCoO2, LiNiO2, and LiCoO2. 1 / 3 Ni 1 / 3 Mn 1 / 3 O2, LiVO2, LiCrO2, etc. As spinel type positive electrode active materials, for example, LiMn2O4, LiCoMnO4, Li2NiMn3O8, LiNi 0.5 Mn 1.5 O4, etc. Examples of the olivine-type positive electrode active material include LiCoPO4, LiMnPO4, and LiFePO4.

[0025] like Figure 1As shown, the target battery 10 has a structure in which a stacked electrode 21 is housed in a laminate 22. The laminate 22 is a laminate film having a base material made of a metal material such as aluminum alloy or stainless steel. The laminate 22 functions as the outer casing of the target battery 10 and as a sealant that seals the stacked electrode 21.

[0026] The target battery 10 of this embodiment has a flat plate shape formed by laminating two laminates 22 . A pair of collector tabs 23A and 23B for extracting power from the target battery 10 penetrates the outer casing and is exposed from the end of the target battery 10 .

[0027] The laminated electrode 21 is a multilayer structure composed of positive plates 11 and negative plates 12, with separators 13 disposed between each of the positive plates 11 and negative plates 12. The separators 13 are disposed between the positive plates 11 and negative plates 12 to prevent short circuits between the positive plates 11 and negative plates 12.

[0028] The positive electrode plates 11 and the negative electrode plates 12 are alternately arranged, and one positive electrode plate 11 and one negative electrode plate 12 facing each other constitute one electrode plate pair. The laminated electrode 21 is formed by laminating a plurality of electrode plate pairs.

[0029] The positive electrode plate 11 includes a rectangular positive electrode current collector 31, with a positive electrode composite material 32 disposed on both sides of the positive electrode current collector 31. The positive electrode current collector 31 is, for example, aluminum foil or aluminum plate. The positive electrode composite material 32 includes, for example, a positive electrode active material, a conductive material, a conductive additive, and a binder. The positive electrode plate 11 has a positive terminal 11A extending from an end of the positive electrode plate 11. The positive terminals 11A extending from the multiple positive electrode plates 11 that constitute the stacked electrode 21 are each connected to a collector tab 23A.

[0030] The negative electrode plate 12 includes a rectangular negative electrode current collector 41. A negative electrode composite material 42 is provided on the surface of the negative electrode current collector 41 that faces the positive electrode plate 11. For example, copper foil or copper plate is used for the negative electrode current collector 41. The negative electrode current collector 41 is an example of a copper member. The negative electrode plate 12 includes a negative electrode terminal 12A extending from an end of the negative electrode plate 12. Each of the negative electrode terminals 12A extending from the plurality of negative electrode plates 12 that constitute the stacked electrode 21 is connected to a collector tab 23B.

[0031] The collector tabs 23A and 23B are formed of a thin plate-shaped metal material such as copper or aluminum, and are exposed to the outside through between the two laminated materials 22 .

[0032] The target battery 10 of this embodiment uses a solid electrolyte as an electrolyte, particularly a battery using a sulfide-based solid electrolyte. For example, the solid electrolyte is disposed between the positive electrode plate 11 and the negative electrode plate 12, replacing the separator 13. In this case, the solid electrolyte not only functions as an electrolyte but also prevents short circuits between the positive electrode plate 11 and the negative electrode plate 12.

[0033] Sulfide solid electrolyte materials are not particularly limited as long as they contain Li and S and exhibit Li ion conductivity. Furthermore, the Li contained in sulfide solid electrolyte materials generally dissolves in treatment fluids such as water. Furthermore, sulfide solid electrolyte materials preferably do not leave any insoluble components after reaction with the treatment fluid. This facilitates recovery of the positive electrode active material.

[0034] Examples of sulfide solid electrolyte materials include materials containing Li, S, and a third component A. The third component A may include at least one selected from the group consisting of P, Ge, B, Si, I, Al, Ga, and As. In the present invention, the sulfide solid electrolyte material is preferably a compound using Li2S and a sulfide MS other than Li2S. Specifically, examples include Li2S-P2S5 compounds, Li2S-SiS2 compounds, and Li2S-GeS2 compounds. Among these, Li2S-P2S5 compounds are preferred due to their high Li ion conductivity. Furthermore, when the molar ratio of Li2S to the sulfide MS is xLi2S-(100-x)MS, x preferably satisfies the relationship 50 ≤ x ≤ 95, and more preferably 60 ≤ x ≤ 85. It should be noted that the Li2S-P2S5 compound refers to a sulfide solid electrolyte material using Li2S and P2S5. The same applies to other compounds. For example, an amorphous Li 2 S—P 2 S 5 compound can be obtained by performing a mechanical milling method or a melt quenching method using Li 2 S and P 2 S 5 .

[0035] In addition, the sulfide solid electrolyte material of the present invention can be amorphous or crystalline. The crystalline sulfide solid electrolyte material can be obtained, for example, by sintering an amorphous sulfide solid electrolyte material. In addition, the sulfide solid electrolyte material of the present invention preferably has cross-linked sulfur. This is because the Li ion conductivity of the sulfide solid electrolyte material is high. In addition, in the case of having cross-linked sulfur, there are the following advantages: hydrogen sulfide is easily generated, and the Li contained in the sulfide solid electrolyte material is easily dissolved in the treatment liquid. In addition, in particular, in the present invention, the sulfide solid electrolyte material is preferably Li7P3S 11 This is because Li ion conductivity is high. It should be noted that Li7P3S 11 It is a sulfide glass ceramic of Li2S-P2S5 compound. In addition, in the present invention, the sulfide solid electrolyte material is preferably a thio-LISICON type compound, for example, preferably composed of Li a P b Ge c S d(2.8≤a≤4.2, 0.1≤b≤1.2, 0.1≤c≤1.2, 3≤d≤5) The average particle size of the sulfide solid electrolyte material is, for example, in the range of 1 nm to 100 μm, preferably in the range of 10 nm to 30 μm.

[0036] [2. Battery disposal method]

[0037] Figure 2 This is a diagram showing a method of handling a battery.

[0038] In the deactivation step S1, the contents of the target battery 10 are deactivated. In the deactivation step S1, after the laminate 22 is opened or cut to allow the contents of the target battery 10 to come into contact with the treatment liquid, the treatment liquid is used to deactivate the target battery 10. The treatment liquid can be water, methanol, ethanol, acetone, or other liquids, but water is used in this embodiment.

[0039] In the deactivation step S1, water vapor is used to react the sulfide-based solid electrolyte in the target battery 10 with water. For example, the target battery 10 is unsealed to expose at least a portion of its contents, and the unsealed target battery 10 is placed in a water vapor atmosphere. Specifically, one method involves placing the target battery 10 in a processing container containing water vapor. In this case, the interior of the processing container is a high-humidity environment, with a humidity above a specified level. Alternatively, the interior of the processing container can be a high-temperature, high-humidity environment. Specifically, the interior of the processing container is maintained at a specified temperature and humidity. The specified humidity is, for example, 80% or higher. The specified temperature is preferably higher than room temperature and does not promote morphological changes (such as oxidation) of the nickel, cobalt, and manganese contained in the positive electrode active material. For example, a temperature of 50°C to 200°C is possible.

[0040] In the deactivation step S1, the contents of the target battery 10 are exposed to water vapor rather than liquid water, preventing the sulfide-based solid electrolyte in the target battery 10 from deactivating quickly. Therefore, in the deactivation step S1, sulfides including hydrogen sulfide (H2S) are generated from the sulfide-based solid electrolyte. The generated hydrogen sulfide and other sulfides sulfide the copper foil or copper plate used in the negative electrode current collector 41, forming copper sulfide (including one or more of CuS, Cu2S, and copper sulfides composed of different components). Specifically, the deactivation step S1 is performed under conditions that promote the sulfidation reaction of the copper components of the target battery 10. The sulfide-based solid electrolyte generates a large amount of hydrogen sulfide and other sulfides, thereby converting at least the surface of the copper foil or copper plate of the negative electrode current collector 41 into copper sulfide.

[0041] In the deactivation step S1 , ventilation, suction and exhaust, neutralization, and the like may be performed in response to the generation of excess hydrogen sulfide and other gases that have not reacted with copper.

[0042] Alternatively, the laminate 22 may be removed from the target battery 10 to extract the contents before the deactivation step S1. This has the advantage that aluminum from the laminate 22 will not be mixed into the steps described later.

[0043] After the deactivation step S1, the cutting step S2 is performed. In the cutting step S2, the deactivated target battery 10 is broken or cut using a crusher or other cutting device. The fragments of the target battery 10 cut in the cutting step S2 are called cut pieces.

[0044] The cut pieces obtained by cutting in the cutting process S2 are processed in the extraction process S3. In the extraction process S3, a treatment liquid is applied to the cut pieces so that the soluble components contained in the cut pieces are dissolved in the treatment liquid. As the treatment liquid, alcohol or water can be used, and water is used in this embodiment. For example, in the extraction process S3, a method of dropping or immersing the cut pieces in water or a method of washing the cut pieces with water is adopted. In the extraction process S3, the water-soluble components contained in the cut pieces are dissolved in water. Here, the lithium compound contained in the target battery 10 is dissolved in water, so that the water becomes strongly alkaline.

[0045] The mixture of the cut pieces and water processed in the extraction step S3 is sieved in the screening step S4 to capture solids larger than the sieve holes. The solids captured in the screening step S4 are, for example, aluminum plates or aluminum foils used for the positive electrode current collector 31, and copper foils or copper plates used for the negative electrode current collector 41. In addition, when the target battery 10 with the laminate 22 is cut in the cutting step S2, the solids captured in the screening step S4 include fragments of the laminate 22. The portion that has passed through the sieve in the screening step S4 is referred to as a pass-through. The pass-through is a mixture of solids finer than the sieve holes and an aqueous solution.

[0046] The solids collected in the screening step S4 are processed in a copper recovery step (not shown) to recover copper from the solids. The remaining copper after recovery includes, in addition to aluminum foil and other materials, the positive electrode active material (NCM) adhering to the surface of the solids. This remaining portion can also be processed together with the pass-through material in the stripping step S5.

[0047] In the stripping process S5, the material passing through the screening process S4 is processed together with the aluminum foil containing the positive electrode active material captured in the screening process S4. In the stripping process S5, a process is performed to strip the positive electrode active material from the solid matter contained in the material passing through the screening process S4. Specifically, the process is a method of crushing or stirring the material passing through the screening process S4 or a method of applying a shock wave to the material passing through. Through this process, for example, the positive electrode composite material 32 containing the positive electrode active material can be separated from the aluminum foil serving as the positive electrode collector 31. The stripping process S5 corresponds to an example of a separation process.

[0048] The passed material processed in the stripping process S5 is sieved in the screening process S6 to capture solids larger than the sieve holes. The sieve used in the screening process S6 has finer sieve holes than the sieve used in the screening process S4. That is, in the screening process S6, filtration based on a sieve with finer sieve holes than those in the screening process S4 is performed to capture solids. The solids captured in the screening process S6 are, for example, relatively large solids among the solids that have passed through the screening process S4. The solids mainly come from the aluminum plate and aluminum foil used in the positive electrode collector 31, and sometimes also include the copper foil or copper plate used in the negative electrode collector 41, the laminate 22, etc.

[0049] The material that passed through the sieve in screening step S6 is filtered in filtration step S7. In filtration step S7, the fine solids and liquid contained in the material are separated using a filter material with finer mesh than the sieve used in screening step S6. The liquid separated in filtration step S7 contains lithium compounds, etc., and therefore undergoes lithium recovery processing (not shown). Lithium recovery can be achieved using known methods such as the Lithium Separation Method by Ionic Conductor (LiSMIC).

[0050] The solids collected in the filtration step S7 undergo a binder removal process in the binder removal step S8. In the binder removal step S8, the binder contained in the solids is removed in a treatment environment that does not cause morphological changes (such as oxidation) in the nickel, cobalt, and manganese contained in the positive electrode active material. For example, in the binder removal step S8, a binder-dissolving solvent is added to the solids, and the solvent dissolves the binder to remove the binder. Removing the solvent and binder from the solids can be performed, for example, by filtration or liquid separation.

[0051] In the water dissolving step S9, water is added to the solid material treated in the binder removal step S8. In the water dissolving step S9, the solid material and water are stirred to form a slurry. The water dissolving step S9 corresponds to an example of a treatment step.

[0052] The slurry generated in the water dissolution step S9 is processed in the flotation separation step S10. The flotation separation step S10 is a step of separating copper fragments from copper components from solids contained in the slurry by flotation separation. The details of the flotation separation step S10 will be described later.

[0053] Recovery step S11 is a step for recovering the positive electrode active material from the slurry separated from the copper in the floatation separation step S10. In recovery step S11, the positive electrode active material is obtained by, for example, removing moisture from the slurry. In recovery step S11, solids in the slurry are collected, for example, by filtration, and the collected solids are dried. When the solid is heated during drying, the temperature of the solid is preferably a temperature that does not cause morphological changes (such as oxidation) of the nickel, cobalt, and manganese contained in the positive electrode active material. Specifically, the temperature of the solid during drying or the upper limit of the heating temperature is preferably set to 200°C or less.

[0054] [3. Details of the flotation separation process]

[0055] Figure 3 It is a schematic diagram showing a treatment example in the flotation separation step S10.

[0056] In the flotation separation step S10, for example, multiple stages of separation are performed using the flotation separation system 2. Prior to separation using the flotation separation system 2, in the flotation separation step S10, a collector and a frother are added to the slurry generated in the water dissolution step S9. These can be commercially available flotation reagents.

[0057] A collector is a material that has the effect of making the mesophilicity of a predetermined substance in the slurry hydrophobic and causing the substances to aggregate. For example, various commercially available collectors and coagulants can be used. Examples of collectors include sulfide-based collectors. A specific example is PAX (manufactured by Al MTT Co., Ltd.).

[0058] The foaming agent may be any component that foams the slurry, and examples thereof include methyl isobutyl carbinol (MIBC). Other foaming agents may also be used.

[0059] The floatation separation system 2 is an example of a multi-stage floatation separation system using a plurality of separation tanks 3. Collectors, foaming agents and other additives may also be added to the floatation separation system. Figure 3 The slurry is added to the slurry before the slurry is put into the separation tank 3. In addition, in the separation tank 3, a collector, a foaming agent and other additives can also be added to the slurry and stirred.

[0060] The floatation separation system 2 selectively recovers hydrophobic particles and fragments from the components contained in the slurry processed in the water-soluble step S9. The hydrophobic particles are, for example, fragments of copper foil and copper plate from copper members.

[0061] The flotation separation system 2 uses separation tanks 3A, 3B, 3C, 3D, 3E, and 3F. In this embodiment, these are described as separation tanks 3 without distinguishing them.

[0062] The slurry produced in the water dissolution step S9 is placed in the separation tank 3A. As described above, a collector, a foaming agent, and other additives may be added to the slurry in advance. If the slurry is placed in the separation tank 3A without the addition of a collector, a foaming agent, and other additives, the collector and foaming agent are added to the separation tank 3A and stirred. Other additives may also be added at this time.

[0063] In the separation tank 3 , the components that aggregate and float are referred to as froth and are denoted by the reference symbol FL. Furthermore, in the separation tank 3 , the liquid or slurry components below the froth are referred to as tail water and are denoted by the reference symbol TA.

[0064] In the separation tank 3A, the slurry is subjected to flotation for a predetermined period of time, causing the hydrophobic particles and debris contained in the slurry to float, thereby separating the foam FL1 from the tail water TA1. The foam FL1 and tail water TA1 separated in the separation tank 3A are removed separately, with the tail water TA1 being fed into the separation tank 3B and the foam FL being fed into the separation tank 3D described later. The separation tank 3A is, for example, a flotation machine equipped with a stirring mechanism (not shown) with a propeller and an air supply mechanism. This flotation machine performs flotation for a predetermined period of time by stirring the slurry with the propeller and supplying air to the slurry with air using the air supply mechanism.

[0065] The tail water TA1 fed into the separation tank 3B is separated into froth FL2 and tail water TA2 by flotation for a predetermined period of time. The froth FL2 is removed from the separation tank 3B and fed into the separation tank 3D. The tail water TA2 is removed from the separation tank 3B and fed into the separation tank 3C.

[0066] The tail water TA2 fed into the separation tank 3C can be separated into froth FL3 and tail water TA3 by flotation for a predetermined time. The froth FL3 is taken out of the separation tank 3C and fed into the separation tank 3D. The tail water TA3 is processed in the recovery step S11.

[0067] Thus, the foamy substances FL1, FL2, and FL3 separated in the three stages of separation tanks 3A, 3B, and 3C from the slurry generated in the water dissolution step S9 are removed to form tail water TA3. Since tail water TA3 has been freed of most of the components that can be separated by floatation separation, the purity of the positive electrode active material is high. Therefore, in the recovery step S11, positive electrode active material with low impurities can be recovered.

[0068] Foams FL1, FL2, and FL3 are fed into separation tank 3D. In separation tank 3D and separation tank 3E, the positive electrode active material contained in foams FL1, FL2, and FL3 is separated. Specifically, foams FL1, FL2, and FL3 fed into separation tank 3D can be separated into foam FL4 and tail water TA4 through flotation for a predetermined period of time. Foam FL4 is recovered from separation tank 3D and fed into separation tank 3F, described below. Tail water TA4 is fed into separation tank 3E.

[0069] The tail water TA4 fed into the separation tank 3E can be separated into a foamy substance FL5 and tail water TA5 by flotation for a predetermined period of time. The foamy substance FL5 is removed from the separation tank 3C and fed into the separation tank 3F. The tail water TA5 is fed into the separation tank 3A. The tail water TA5 is obtained by extracting the majority of the positive electrode active material as foamy substances FL1, FL2, FL3, FL4, and FL5 in the separation tanks 3A, 3B, 3C, 3D, and 3E, respectively. However, since it may contain hydrophobic solids, it is not directly sent to the recovery process S11, but is processed again in the separation tank 3A. This can improve the recovery rate of the positive electrode active material.

[0070] Foams FL4 and FL5 are fed into the separation tank 3F. The foams FL4 and FL5 fed into the separation tank 3F can be separated into foam FL6 and tail water TA6 through flotation for a predetermined period of time. The foam FL6 is removed from the separation tank 3F and processed as a component primarily containing copper in a copper recovery step (not shown), similar to the solids collected in the screening step S4. The tail water TA6 is fed into the separation tank 3D and subjected to further floatation separation.

[0071] A stirring mechanism (not shown) having a propeller and an air supply mechanism (not shown) may be provided in part or all of the separation tanks 3B to 3F, similarly to the separation tank 3A. In the separation tanks having the stirring mechanism, flotation can be performed for a predetermined time by stirring the slurry with the propeller and supplying air to the slurry with the air supply mechanism.

[0072] In this embodiment, since the deactivation step S1 is performed under conditions where a large amount of hydrogen sulfide is generated, most of the copper components of the target battery 10 react with hydrogen sulfide to form copper sulfide. Consequently, at least a portion of the surface of the copper component contained in the slurry generated in the water dissolution step S9 forms copper sulfide. Copper sulfide is hydrophobic, and the addition of a sulfide-based collector enhances its capture efficiency. Therefore, the copper component contained in the slurry can be efficiently captured as a foamy substance in the flotation separation step S10, allowing for easy recovery. In particular, when copper is mixed with the positive electrode active material, it is difficult to improve the purity of the positive electrode active material. However, when the mixed copper is sulfided, it can be effectively separated in the flotation separation step S10. Therefore, solids from the copper components can be efficiently recovered in the flotation separation step S10, and positive electrode active material with low impurities can be recovered in the recovery step S11.

[0073] The present inventors conducted experiments in which a slurry with a purity of 80% positive electrode active material was prepared at a slurry concentration of 20% and processed in a flotation separation system 2. The results achieved a recovery rate of over 95%. In this example, PAX (trade name) was used as the collector and MIBC as the foaming agent.

[0074] As described above, the treatment method for the target battery 10 described in this embodiment uses an all-solid-state battery constructed using copper components. The target battery 10 comprises a positive electrode comprising a positive electrode composite material 32 containing a positive electrode active material; a negative electrode; and a sulfide-based solid electrolyte. This method includes a deactivation step S1 for deactivating the contents of the target battery under conditions that promote a sulfidation reaction in the copper components; and a separation step for separating the positive electrode composite material from the material constituting the positive electrode. An example of the separation step is a peeling step S5. The method includes a treatment step for forming a slurry containing the positive electrode composite material separated in the separation step; and a flotation separation step S10 for removing solids from the copper components from the slurry using flotation separation. An example of the treatment step is a water dissolution step S9. The method includes a recovery step S11 for recovering the positive electrode active material from the slurry from which the solids have been removed in the flotation separation step S10.

[0075] Thus, a proposal is made to facilitate separation of the copper component in the flotation separation step S10 by performing the deactivation step S1 under conditions that promote sulfidation of the copper component contained in the target battery 10. Consequently, the copper component can be efficiently separated in the flotation separation step S10, allowing high-purity positive electrode active material to be recovered in the recovery step S11. Consequently, when recovering the positive electrode active material containing at least one of nickel, cobalt, and manganese, contamination of other metals can be suppressed, resulting in improved recovery efficiency.

[0076] In the above-described battery treatment method, in the deactivation step S1 , the contents of the target battery 10 are placed in a treatment atmosphere containing water vapor, thereby deactivating the contents of the target battery 10 .

[0077] This makes it possible to easily achieve conditions that promote the sulfation of the copper component contained in the target battery 10 .

[0078] In the above-described battery processing method, in the recovery step S11 , the tail water separated from the solid matter in the floatation separation step S10 is dried to recover the positive electrode active material.

[0079] This makes it possible to easily recover the positive electrode active material containing at least any one of nickel, cobalt, and manganese.

[0080] In the above-described battery treatment method, in the flotation separation step S10 , a collector and a foaming agent are added to the slurry, thereby removing solid matter by flotation separation.

[0081] Thus, in the flotation separation step S10 , the copper component can be efficiently separated from the slurry containing the positive electrode active material.

[0082] In the above-mentioned battery processing method, the copper member is a copper foil constituting the negative electrode.

[0083] Thus, when the positive electrode active material is recovered from the target battery 10 using the copper foil as the negative electrode, the incorporation of components derived from the copper foil can be suppressed, thereby improving the recovery efficiency.

[0084] [4. Other Implementation Methods]

[0085] The above-described embodiment is merely one proposed embodiment of the present invention, and can be arbitrarily modified and applied without departing from the spirit of the present invention.

[0086] While the above embodiment describes an example of treating a target battery 10 having a ternary positive electrode material containing nickel, cobalt, and manganese, the battery treatment method disclosed herein is not limited thereto. The battery treatment method disclosed herein can be applied to batteries using materials containing any one or more of nickel, cobalt, and manganese without further limitation.

[0087] The shape of the target battery 10 described in the above embodiment is merely an example. The present disclosure can also be applied to cylindrical or rectangular batteries in which the battery material is housed in an outer casing made of iron, aluminum, or the like. In other words, the present disclosure is applicable to all-solid-state batteries other than laminated batteries.

[0088] [5. Solutions supported by the above-mentioned implementation methods]

[0089] The above-mentioned embodiment supports the following schemes.

[0090] (Scheme 1) A battery processing method, wherein the battery processing method uses an all-solid-state battery composed of a copper component as a target battery, the all-solid-state battery having: a positive electrode having a positive electrode composite material containing a positive electrode active material; a negative electrode; and a sulfide-based solid electrolyte, wherein the battery processing method includes: a deactivation step in which the contents of the target battery are deactivated under conditions that promote a sulfidation reaction of the copper component; a separation step in which the positive electrode composite material is separated from a material constituting the positive electrode; a treatment step in which a slurry containing the positive electrode composite material separated in the separation step is formed; a flotation separation step in which solids from the copper component are removed from the slurry by flotation separation; and a recovery step in which the positive electrode active material is recovered from the slurry from which the solids have been removed in the flotation separation step.

[0091] According to the battery treatment method of claim 1, by performing the deactivation step under conditions that promote sulfidation of the copper component contained in the target battery, the copper component can be efficiently separated in the flotation separation step. Consequently, a high-purity positive electrode active material can be recovered in the recovery step. Consequently, when recovering a positive electrode active material containing at least one of nickel, cobalt, and manganese, contamination of other metals can be suppressed, thereby improving recovery efficiency.

[0092] (Structure 2) The battery treatment method according to Structure 1, wherein in the deactivation step, the contents of the target battery are placed in a treatment environment containing water vapor, thereby deactivating the contents of the target battery.

[0093] According to the battery treatment method of claim 2, conditions that promote sulfidation of the copper component contained in the target battery can be easily achieved.

[0094] (Structure 3) The battery processing method according to Structure 1 or Structure 2, wherein, in the recovery step, the tail water separated from the solid matter in the floatation separation step is dried to recover the positive electrode active material.

[0095] According to the battery processing method of claim 3, the positive electrode active material containing at least any one of nickel, cobalt, and manganese can be easily recovered.

[0096] (Structure 4) The battery processing method according to any one of Structures 1 to 3, wherein in the flotation separation step, a collector and a foaming agent are added to the slurry, thereby removing the solid matter by flotation separation.

[0097] According to the battery processing method of claim 4, the copper component can be efficiently separated from the slurry containing the positive electrode active material by removing solid matter in the flotation separation step.

[0098] (Structure 5) The battery processing method according to any one of Structures 1 to 4, wherein the copper member is a copper foil constituting the negative electrode.

[0099] According to the battery processing method of claim 5, when recovering the positive electrode active material from a target battery using copper foil as the negative electrode, the incorporation of components derived from the copper foil can be suppressed, thereby achieving improved recovery efficiency.

Claims

1. A battery treatment method, wherein the battery treatment method uses an all-solid-state battery composed of a copper component as the target battery, the all-solid-state battery comprising: a positive electrode having a positive electrode composite material containing a positive electrode active material; a negative electrode; and a sulfide-based solid electrolyte, wherein: The battery processing method includes: a deactivation step of deactivating the contents of the target battery under conditions that promote a sulfidation reaction of the copper member; a separation step of separating the positive electrode composite material from a material constituting the positive electrode; a treatment step of forming a slurry containing the positive electrode composite material separated in the separation step; a flotation separation step of removing solids from the copper member from the slurry by flotation separation; and A recovery step of recovering the positive electrode active material from the slurry from which the solid matter has been removed in the floatation separation step.

2. The battery processing method according to claim 1, wherein: In the deactivation step, the contents of the target battery are placed in a treatment environment containing water vapor, thereby deactivating the contents of the target battery.

3. The battery processing method according to claim 1, wherein: In the recovery step, the tail water separated from the solid matter in the floatation separation step is dried to recover the positive electrode active material.

4. The battery processing method according to any one of claims 1 to 3, wherein: In the flotation separation step, a collector and a foaming agent are added to the slurry, thereby removing the solid matter by flotation separation.

5. The battery processing method according to claim 1, wherein: The copper member is a copper foil constituting the negative electrode.

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