Processing method for battery

Abstract

To improve collection efficiency by suppressing mixture of the other metal in the step of collecting a valuable metal containing nickel, cobalt or manganese from a used secondary battery.SOLUTION: A processing method for a battery defines as a target battery an all-solid battery which includes a cathode including a cathode mixture containing a cathode active material, an anode and a sulfide-based solid electrolyte and is configured using a copper member. The processing method for the battery includes: a deactivation step of deactivating the content of the target battery under a condition that a sulfurization reaction is promoted; a separation step of separating the cathode mixture from the material constituting the cathode; a processing step of forming a slurry including the cathode mixture which is separated in the separation step; a float selection step of removing a solid derived from the copper member from the slurry by float selection; and a collection step of collecting the cathode active material from the slurry from which the solid is removed in the float selection step.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a method for treating a battery. [Background technology]

[0002] In recent years, research and development into the recycling of secondary batteries, which contribute to energy efficiency, has been conducted to ensure that more people have access to affordable, reliable, sustainable, and advanced energy. For example, some lithium-ion batteries and all-solid-state batteries have stacked electrodes in which positive and negative electrodes are stacked with a separator between them. The positive electrode mixture in these types of batteries uses a ternary cathode material (NCM) consisting of nickel, cobalt, and manganese. Therefore, methods have been proposed to recover 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. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. WO2010 / 106618 Summary of the Invention [Problem to be solved by the invention]

[0005] Metallic materials such as aluminum and copper are used in secondary batteries, and copper foil is used as a negative electrode current collector, for example. These metallic materials are sometimes contaminated with positive electrode materials containing nickel, cobalt, manganese, etc. when they are recovered from secondary batteries. Therefore, it has been desired to suppress the contamination of metallic materials in order to improve the recovery efficiency of positive electrode materials. In order to solve the above problems, the present application aims to improve the recovery efficiency of valuable metals, including nickel, cobalt, and manganese, by suppressing the inclusion of other metals in the process of recovering them from used secondary batteries, thereby contributing to energy efficiency. [Means for solving the problem]

[0006] One aspect of the present disclosure is a battery treatment method for an all-solid-state battery configured using copper members, the all-solid-state battery having a positive electrode having a positive electrode composite containing a positive electrode active material, a negative electrode, and a sulfide-based solid electrolyte, the battery treatment method including: a deactivation step of deactivating contents of the target battery under conditions that promote a sulfidation reaction of the copper members; a separation step of separating the positive electrode composite from materials that constitute the positive electrode; a treatment step of forming a slurry containing the positive electrode composite separated in the separation step; a flotation step of removing solid matter derived from the copper members from the slurry by flotation; and a recovery step of recovering the positive electrode active material from the slurry from which the solid matter has been removed in the flotation step. [Effects of the Invention]

[0007] According to one aspect of the present disclosure, in a process for recovering valuable metals including nickel, cobalt, or manganese from used secondary batteries, it is possible to suppress the incorporation of metals originating from copper components of the batteries, thereby improving the recovery efficiency of valuable metals. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing the configuration of a target battery as an example of a battery to which the present disclosure is applied. [Figure 2] FIG. 1 is a diagram illustrating a method for treating a battery. [Figure 3] FIG. 2 is a schematic diagram showing an example of processing in a flotation step. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0010] [1. Target battery configuration] FIG. 1 is a diagram showing the configuration of a target battery 10 as an example of a battery to which the present disclosure is applied, and schematically shows a cross section of the target battery 10. The target battery 10 is a secondary battery capable of charging and discharging. The target battery 10 described in this embodiment is a laminated battery in which battery materials are encapsulated in a laminate material 22, and has an overall flat plate shape. The target battery 10 can be referred to as a pouch-type battery, a laminated battery cell, a pouch-type battery cell, a lithium-ion battery cell, a battery module, or the like.

[0011] The subject battery 10 is a secondary battery known as a lithium-ion battery, which has attracted attention as an electricity storage device with a 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. Examples of positive electrode active materials include ternary cathode materials (NCMs) containing nickel, cobalt, and manganese. Examples of negative electrode active materials for lithium-ion batteries include carbon-based materials. All-solid-state batteries, which use a solid electrolyte as the electrolyte for lithium-ion batteries, are also known.

[0012] Nickel, cobalt, and manganese, which are used as positive electrode active materials in lithium-ion batteries, all-solid-state batteries, and the like, are known as valuable metals, and there is a demand for their recovery from used batteries. Therefore, this embodiment discloses an efficient method for recovering these metals. In the disclosed method, the electrode material to be recovered is a valuable metal contained in the target battery 10, more specifically, an NCM-related compound contained in the positive electrode active material of the positive electrode current collector 31. In other words, it is a substance containing one or more of nickel, cobalt, and manganese.

[0013] More specifically, the positive electrode active material is a material capable of absorbing and releasing 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 LiCo 1 / 3 Ni 1 / 3 Mn 1 / 3 Examples of spinel-type positive electrode active materials include LiMn2O4, LiCoMnO4, Li2NiMn3O8, LiNi 0.5 Mn 1.5 Examples of olivine-type positive electrode active materials include LiCoPO4, LiMnPO4, and LiFePO4.

[0014] 1, the target battery 10 has a configuration in which a laminated electrode 21 is housed in a laminate material 22. The laminate material 22 is a laminate film whose base material is a metal material such as an aluminum alloy or stainless steel. The laminate material 22 functions as an exterior body of the target battery 10 and as a seal that seals the laminated electrode 21.

[0015] The target battery 10 of this embodiment has a flat plate shape formed by bonding two sheets of laminate material 22 together, and a pair of current collecting tabs 23A, 23B for extracting power from the target battery 10 penetrate the outer casing and are exposed from the end of the target battery 10.

[0016] The laminated electrode 21 is a multilayer body in which positive electrode plates 11 and negative electrode plates 12 are stacked, and a separator 13 is disposed between each positive electrode plate 11 and negative electrode plate 12. The separator 13 is disposed between the positive electrode plate 11 and the negative electrode plate 12 to prevent a short circuit between the positive electrode plate 11 and the negative electrode plate 12.

[0017] The positive electrode plates 11 and the negative electrode plates 12 are arranged alternately, and one positive electrode plate 11 and one negative electrode plate 12 facing each other constitute one electrode plate pair. A stacked electrode 21 is formed by stacking a plurality of electrode plate pairs.

[0018] The positive electrode plate 11 includes a rectangular positive electrode current collector 31, and a positive electrode composite 32 is provided on both sides of the positive electrode current collector 31. The positive electrode current collector 31 is, for example, an aluminum foil or an aluminum plate. The positive electrode composite 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 electrode terminal 11A extending from an end of the positive electrode plate 11. The positive electrode terminals 11A extending from the multiple positive electrode plates 11 constituting the stacked electrode 21 are each connected to a current collecting tab 23A.

[0019] 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 facing the positive electrode plate 11. The negative electrode current collector 41 is made of, for example, copper foil or copper plate. The negative electrode current collector 41 is an example of a copper member. The negative electrode plate 12 has a negative electrode terminal 12A extending from an end of the negative electrode plate 12. The negative electrode terminals 12A extending from the multiple negative electrode plates 12 that make up the stacked electrode 21 are each connected to a current collecting tab 23B.

[0020] The current collecting tabs 23A and 23B are formed from a thin metal plate such as copper or aluminum, and pass between the two laminate materials 22 and are exposed to the outside.

[0021] The subject battery 10 of this embodiment is a battery that uses a solid electrolyte, particularly a sulfide-based solid electrolyte. The solid electrolyte is disposed, for example, between the positive electrode plate 11 and the negative electrode plate 12 in place of the separator 13. In this case, the solid electrolyte not only functions as an electrolyte but also prevents short-circuiting between the positive electrode plate 11 and the negative electrode plate 12.

[0022] The sulfide solid electrolyte material is not particularly limited as long as it contains Li and S and has Li ion conductivity. Furthermore, the Li contained in the sulfide solid electrolyte material is usually dissolved in a treatment liquid such as water. Furthermore, it is preferable that the sulfide solid electrolyte material does not leave any insoluble components when reacting with the treatment liquid. This is because this makes it easier to recover the positive electrode active material.

[0023] Examples of sulfide solid electrolyte materials include those containing Li, S, and a third component A. Examples of the third component A include at least one selected from the group consisting of P, Ge, B, Si, I, Al, Ga, and As. In particular, in the present invention, a sulfide solid electrolyte material is preferably a compound using Li2S and a sulfide MS other than Li2S. Specific examples include a Li2S-P2S5 compound, a Li2S-SiS2 compound, and a Li2S-GeS2 compound. Among these, a Li2S-P2S5 compound is preferred because of its 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. 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 Li2S-P2S5 compound can be obtained by mechanical milling or melt quenching using Li2S and P2S5.

[0024] The sulfide solid electrolyte material of the present invention may be amorphous or crystalline. A crystalline sulfide solid electrolyte material can be obtained, for example, by firing an amorphous sulfide solid electrolyte material. The sulfide solid electrolyte material of the present invention preferably has bridging sulfur. This is because the sulfide solid electrolyte material has high Li ion conductivity. Furthermore, when bridging sulfur is present, hydrogen sulfide is easily generated, which has the advantage of making it easy to dissolve Li contained in the sulfide solid electrolyte material in the treatment solution. Particularly in the present invention, the sulfide solid electrolyte material is preferably Li7P3S 11 This is because it has high Li ion conductivity. 11 is a sulfide glass ceramic of the Li2S-P2S5 compound. In the present invention, the sulfide solid electrolyte material is preferably a thio-LISICON type compound, for example, 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) is preferable. The average particle size of the sulfide solid electrolyte material is, for example, in the range of 1 nm to 100 μm, and preferably in the range of 10 nm to 30 μm.

[0025] [2. Battery disposal method] FIG. 2 is a diagram showing a method for treating a battery. In the deactivation step S1, the contents of the target battery 10 are deactivated. In the deactivation step S1, the laminate material 22 is opened or cut to expose the contents of the target battery 10 to the treatment liquid, and the contents are then deactivated using the treatment liquid. While water, methyl alcohol, ethyl alcohol, acetone, or other liquids can be used as the treatment liquid, water is used in this embodiment.

[0026] In the deactivation step S1, water vapor is used to react the sulfide-based solid electrolyte of the target battery 10 with water. For example, the target battery 10 is opened so that at least a portion of the contents is exposed, and the opened target battery 10 is placed in a water vapor atmosphere. Specifically, the target battery 10 is placed in a treatment container in which water vapor is present. In this case, the inside of the treatment container is a humid environment, with a humidity level above a predetermined level. Alternatively, the inside of the treatment container may be a high-temperature, high-humidity environment. That is, the inside of the treatment container is set to a predetermined temperature or higher and a predetermined humidity or higher. The predetermined humidity is, for example, 80% or higher. The predetermined temperature is preferably higher than room temperature and does not promote morphological changes (oxidation, etc.) of nickel, cobalt, and manganese contained in the positive electrode active material. For example, a temperature of 50°C or higher and 200°C or lower may be used.

[0027] In the deactivation step S1, the contents of the target battery 10 are exposed to water vapor, not liquid water, to prevent the sulfide-based solid electrolyte of the target battery 10 from being deactivated in a short period of time. Therefore, in the deactivation step S1, sulfides, including hydrogen sulfide (HS), are generated from the sulfide-based solid electrolyte. The hydrogen sulfide and other sulfides generated here sulfurize the copper foil or copper plate used in the negative electrode current collector 41, producing copper sulfide (including one or more of CuS, CuS, and copper sulfides with different compositions). In other words, the deactivation step S1 is performed under conditions that promote the sulfurization reaction of the copper members of the target battery 10. By generating a large amount of hydrogen sulfide and other sulfides from the sulfide-based solid electrolyte, at least the surface of the copper foil or copper plate of the negative electrode current collector 41 is converted to copper sulfide.

[0028] In the deactivation step S1, ventilation, suction and exhaust, neutralization treatment, etc. may be carried out to deal with the generation of excess hydrogen sulfide that has not reacted with copper and other gases. Furthermore, prior to the deactivation step S1, the laminate material 22 may be removed from the target battery 10 to remove the contents. This has the advantage that aluminum derived from the laminate material 22 is not mixed in the steps described below.

[0029] After the deactivation step S1, a cutting step S2 is performed. In the cutting step S2, the deactivated target battery 10 is crushed or cut using a shredder or other cutting device. The pieces of the target battery 10 cut in the cutting step S2 are called cut pieces.

[0030] The cut pieces cut in the cutting step S2 are treated in the extraction step S3. In the extraction step S3, a treatment liquid is added to the cut pieces, and soluble components contained in the cut pieces are dissolved in the treatment liquid. Alcohol or water can be used as the treatment liquid, and water is used in this embodiment. For example, in the extraction step S3, the cut pieces are placed in or immersed in water, or the cut pieces are washed with water. In the extraction step S3, water-soluble components contained in the cut pieces are dissolved in water. Here, the lithium compounds and the like contained in the target battery 10 dissolve in water, making the water strongly alkaline.

[0031] The mixture containing the cut pieces and water processed in the extraction step S3 is sieved in the sieving step S4, and solid matter larger than the mesh size of the sieve is collected. The solid matter collected in the sieving step S4 is, for example, the aluminum plate or aluminum foil used in the positive electrode current collector 31, or the copper foil or copper plate used in the negative electrode current collector 41. Also, if the target battery 10 with the laminate material 22 attached is cut in the cutting step S2, the solid matter collected in the sieving step S4 will include fragments of the laminate material 22. The material that passes through the sieve in the sieving step S4 is called the permeate. The permeate is a mixture of solids finer than the mesh size of the sieve and an aqueous solution.

[0032] The solid matter collected in the sieving step S4 is treated in a copper recovery step (not shown) to recover copper from the solid matter. The remainder after copper recovery includes aluminum foil and other materials, as well as the positive electrode active material (NCM) that was attached to the surface of the solid matter. This remainder may be treated together with the permeated matter in a peeling step S5.

[0033] The material that passes through the sieving step S4 is treated in a peeling step S5 together with the aluminum foil containing the positive electrode active material collected in the sieving step S4. In the peeling step S5, the positive electrode active material is peeled from the solid matter contained in the material that passes through the sieving step S4. Specifically, this treatment is performed by crushing or stirring the material that passes through the sieving step S4, or by applying shock waves to the material that passes through the sieving step S4. This treatment, for example, can separate the positive electrode composite 32 containing the positive electrode active material from the aluminum foil that is the positive electrode current collector 31. The peeling step S5 corresponds to an example of a separation step.

[0034] The material that has passed through the peeling step S5 is sieved in the sieving step S6, and solid matter larger than the mesh size of the sieve is collected. The sieve used in the sieving step S6 has a finer mesh than the sieve used in the sieving step S4. That is, in the sieving step S6, filtration is performed using a sieve with a finer mesh than the sieving step S4, and solid matter is collected. The solid matter collected in the sieving step S6 is, for example, relatively large solid matter that passed through the sieving step S4. This solid matter is mainly derived from the aluminum plate or aluminum foil used in the positive electrode current collector 31, and may also include the copper foil or copper plate, laminate material 22, etc. used in the negative electrode current collector 41.

[0035] The permeate that passed through the sieve in the sieving step S6 is filtered in the filtration step S7. In the filtration step S7, fine solids contained in the permeate are separated from the liquid using a filter material with finer mesh than the sieve used in the sieving step S6. The liquid separated in the filtration step S7 contains lithium compounds and the like, and is therefore subjected to a lithium recovery process (not shown). A known method such as the Li Separation Method by Ionic Conductor (LiSMIC) can be used to recover lithium.

[0036] The solid matter collected in the filtration step S7 is subjected to a binder removal process in the binder removal step S8. In the binder removal step S8, the binder contained in the solid matter is removed in a processing environment that does not cause morphological changes (oxidation, etc.) of the nickel, cobalt, and manganese contained in the positive electrode active material. For example, in the binder removal step S8, a solvent that dissolves the binder is added to the solid matter, and the binder is dissolved by the solvent, thereby removing the binder. The process of removing the solvent and binder from the solid matter can be performed, for example, by filtration or a liquid separation process.

[0037] 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 produce a slurry. The water-dissolving step S9 corresponds to an example of a treatment step.

[0038] The slurry produced in the aqueous dissolution step S9 is treated in a flotation step S10. The flotation step S10 is a step in which copper flakes derived from copper components are separated from the solid matter contained in the slurry by flotation. The details of the flotation step S10 will be described later.

[0039] The recovery step S11 is a step of recovering the positive electrode active material from the slurry separated from the copper in the flotation step S10. In the recovery step S11, for example, the water content of the slurry is removed to obtain the positive electrode active material. In the recovery step S11, for example, the solid in the slurry is collected by filtration, and the collected solid is dried. When the solid is heated during drying, the temperature of the solid is preferably set to a temperature that does not cause morphological changes (oxidation, etc.) of the nickel, cobalt, and manganese contained in the positive electrode active material. Specifically, the upper limit of the temperature of the solid or the heating temperature during drying is preferably set to 200°C or lower.

[0040] [3. Details of the flotation process] FIG. 3 is a schematic diagram showing an example of processing in the flotation step S10. In the flotation step S10, for example, multiple stages of sorting are performed using a flotation system 2. In the flotation step S10, before sorting using the flotation system 2, a collector and a foaming agent are added to the slurry produced in the aqueous dissolution step S9. Commercially available flotation reagents can be used for these.

[0041] The collector is a material that has the effect of making the solvent-philic properties of certain substances in the slurry hydrophobic or of flocculating substances together. For example, various commercially available collectors and flocculants can be used. Examples of collectors include sulfide-based collectors. A specific example is PAX (manufactured by Air MTT LLC).

[0042] The foaming agent may be any component that foams the slurry, such as methyl isobutyl carbinol (MIBC), but other foaming agents may also be used.

[0043] The flotation system 2 is an example of a multi-stage flotation system using multiple separation tanks 3. Collectors, foaming agents, and other additives may be added to the slurry before the slurry is introduced into the separation tank 3 shown in Figure 3. Alternatively, the collectors, foaming agents, and other additives may be introduced into the slurry in the separation tank 3, followed by stirring.

[0044] The flotation system 2 selectively recovers hydrophobic particles and fragments from the components contained in the slurry treated in the water dissolving step S9. The hydrophobic particles are, for example, copper foil or copper plate fragments derived from copper members.

[0045] The flotation system 2 uses separation tanks 3A, 3B, 3C, 3D, 3E, and 3F. In this embodiment, when there is no need to distinguish between these, they will be referred to as separation tanks 3. The slurry produced in the aqueous dissolving step S9 is introduced into the separation tank 3A. As described above, a collector, a foaming agent, and other additives may be added to this slurry in advance. When a slurry to which a collector, a foaming agent, and other additives have not been added is introduced into the separation tank 3A, a collector and a foaming agent are added and stirred in the separation tank 3A. Other additives may also be added at this time.

[0046] In the separation tank 3, the aggregated and suspended components are called froth and are indicated by the symbol FL in the diagram. In addition, in the separation tank 3, the liquid or slurry component below the froth is called tail and are indicated by the symbol TA in the diagram.

[0047] In the separation tank 3A, the slurry is floated for a predetermined time, causing hydrophobic particles and small pieces contained in the slurry to float, allowing separation into froth FL1 and tail TA1. The froth FL1 and tail TA1 separated in the separation tank 3A are then removed, with the tail TA1 being placed in the separation tank 3B and the froth FL being placed in the separation tank 3D described below. The separation tank 3A is, for example, a flotation machine having a stirring mechanism with a propeller and an air supply mechanism (not shown). This flotation machine performs flotation for a predetermined time by stirring the slurry with the propeller and supplying air to the slurry with the air supply mechanism.

[0048] The tail TA1 introduced into separation tank 3B can be separated into froth FL2 and tail TA2 by flotation for a predetermined time. The froth FL2 is removed from separation tank 3B and introduced into separation tank 3D. The tail TA2 is removed from separation tank 3B and introduced into separation tank 3C.

[0049] The tail TA2 introduced into the separation tank 3C can be separated into froth FL3 and tail TA3 by flotation for a predetermined time. The froth FL3 is removed from the separation tank 3C and introduced into the separation tank 3D. The tail TA3 is treated in the recovery step S11.

[0050] In this way, the slurry generated in the aqueous dissolution step S9 is separated in three stages in separation tanks 3A, 3B, and 3C, and the froths FL1, FL2, and FL3 are removed to produce a tail TA3. Since most of the components separable by flotation have been removed from the tail TA3, the purity of the positive electrode active material is high. Therefore, a positive electrode active material with few impurities can be recovered in the recovery step S11.

[0051] Froths FL1, FL2, and FL3 are fed into separation tank 3D. In separation tanks 3D and 3E, the positive electrode active material contained in froths FL1, FL2, and FL3 is separated. That is, froths FL1, FL2, and FL3 fed into separation tank 3D can be separated into froth FL4 and tail TA4 by flotation for a predetermined period of time. Froth FL4 is recovered from separation tank 3D and fed into separation tank 3F, which will be described later. Tail TA4 is fed into separation tank 3E.

[0052] The tail TA4 introduced into separation tank 3E can be separated into froth FL5 and tail TA5 by flotation for a predetermined time. Froth FL5 is removed from separation tank 3C and introduced into separation tank 3F. Tail TA4 is introduced into separation tank 3A. Tail TA4 is the portion of froths FL1, FL2, and FL3 that contains a large amount of positive electrode active material, but because it may contain hydrophobic solids, it is not sent directly to recovery step S11 but is treated again in separation tank 3A. This can improve the recovery rate of positive electrode active material.

[0053] Froths FL4 and FL5 are fed into separation tank 3F. Froths FL4 and FL5 fed into separation tank 3F can be separated into froth FL6 and tail TA6 by flotation for a predetermined period of time. Froth FL6 is removed from separation tank 3F and treated in a copper recovery process (not shown) as a component mainly containing copper, for example, similar to the solid matter collected in sieving process S4. Tail TA6 is fed into separation tank 3D and again subjected to flotation separation. Some or all of separation tanks 3B to 3F may be provided with a stirring mechanism and an air supply mechanism (not shown) having a propeller, similar to separation tank 3A. In a separation tank having a stirring mechanism, the slurry may be stirred by the propeller and air may be supplied to the slurry by the air supply mechanism, thereby performing flotation for a predetermined time.

[0054] In this embodiment, the deactivation step S1 is performed under conditions that generate a large amount of hydrogen sulfide. Therefore, many of the copper components of the target battery 10 react with hydrogen sulfide to produce copper sulfide. Therefore, at least a portion of the surface of the copper components contained in the slurry produced in the aqueous dissolution step S9 is copper sulfide. Copper sulfide is hydrophobic, and the addition of a sulfide-based collector enhances the collection effect. Therefore, the copper components contained in the slurry can be efficiently collected as froth in the flotation step S10 and easily recovered. In particular, it is difficult to increase the purity of a cathode active material containing copper. However, if the copper is sulfurized, it can be effectively separated in the flotation step S10. Therefore, solids derived from the copper components can be efficiently recovered in the flotation step S10, and a cathode active material with fewer impurities can be recovered in the recovery step S11.

[0055] In a test conducted by the inventors, a positive electrode active material with a purity of 80% was treated as a slurry with a pulp concentration of 20% in a flotation system 2, and a recovery rate of 95% or more was achieved. In this example, PAX (trade name) was used as the collector and MIBC was used as the foaming agent.

[0056] As described above, the treatment method for the target battery 10 described in this embodiment uses an all-solid-state battery configured using copper components, including a cathode having a cathode composite 32 containing a cathode active material, an anode, and a sulfide-based solid electrolyte. This method includes a deactivation step S1 in which the contents of the target battery are deactivated under conditions that promote a sulfidation reaction of the copper components, and a separation step in which the cathode composite is separated from the materials constituting the cathode. The separation step is, for example, a stripping step S5. This method also includes a treatment step in which a slurry containing the cathode composite separated in the separation step is formed, and a flotation step S10 in which solids derived from the copper components are removed from the slurry by flotation. The treatment step is, for example, a water dissolution step S9. This method also includes a recovery step S11 in which the cathode active material is recovered from the slurry from which the solids have been removed in the flotation step S10.

[0057] According to this, by performing the deactivation step S1 under conditions that promote sulfidation of the copper component contained in the target battery 10, the copper component is made easy to separate in the flotation step S10. Therefore, the copper component can be efficiently separated in the flotation step S10, and a high-purity positive electrode active material can be recovered in the recovery step S11. Therefore, when recovering a positive electrode active material containing at least one of nickel, cobalt, and manganese, it is possible to suppress the incorporation of other metals, thereby improving recovery efficiency.

[0058] In the above-described battery treatment method, in the deactivation step S1, the contents of the target battery 10 are deactivated by placing the contents of the target battery 10 in a treatment environment containing water vapor. This makes it possible to easily realize conditions that promote sulfurization of the copper component contained in the target battery 10.

[0059] In the above-described battery treatment method, in the recovery step S11, the tail separated from the solid matter in the flotation step S10 is dried to recover the positive electrode active material. This allows the positive electrode active material containing at least one of nickel, cobalt, and manganese to be easily recovered.

[0060] In the above-described battery treatment method, in the flotation step S10, a collector and a foaming agent are added to the slurry, and solids are removed by flotation. This allows the copper component to be efficiently separated from the slurry containing the positive electrode active material in the flotation step S10.

[0061] In the above-described battery treatment method, the copper member is copper foil that constitutes the negative electrode. This makes it possible to prevent components derived from the copper foil from being mixed in when recovering the positive electrode active material from the target battery 10 that uses copper foil as the negative electrode, thereby improving recovery efficiency.

[0062] 4. Other Embodiments The above embodiment is merely one embodiment of the present invention, and any modifications and applications are possible without departing from the spirit of the present invention.

[0063] In the above embodiment, an example of treating the target battery 10 having a ternary positive electrode material containing nickel, cobalt, and manganese has been described, but the subject of the battery treatment method of the present disclosure is not limited thereto. The battery treatment method of the present disclosure can be applied to batteries using materials containing one or more of nickel, cobalt, and manganese, and there are no other limitations.

[0064] Furthermore, the shape of the subject battery 10 described in the above embodiment is merely an example, and the present disclosure may be applied to cylindrical or prismatic batteries in which battery materials are housed in an exterior made of iron, aluminum, etc. In other words, the present disclosure is applicable to all-solid-state batteries other than laminated types.

[0065] [5. Configurations supported by the above embodiments] The above embodiment supports the following configurations.

[0066] (Configuration 1) A battery treatment method for an all-solid-state battery configured using copper members, the all-solid-state battery having a positive electrode having a positive electrode composite containing a positive electrode active material, a negative electrode, and a sulfide-based solid electrolyte, the battery treatment method comprising: a deactivation step of deactivating the contents of the target battery under conditions that promote a sulfidation reaction of the copper members; a separation step of separating the positive electrode composite from materials that constitute the positive electrode; a treatment step of forming a slurry that contains the positive electrode composite separated in the separation step; a flotation step of removing solid matter derived from the copper members from the slurry by flotation; and a recovery step of recovering the positive electrode active material from the slurry from which the solid matter has been removed in the flotation step. According to the battery treatment method of the first aspect, the deactivation step is performed under conditions that promote sulfidation of the copper component contained in the target battery, thereby enabling efficient separation of the copper component in the flotation step. This allows high-purity cathode active material to be recovered in the recovery step. Therefore, when recovering a cathode active material containing at least one of nickel, cobalt, and manganese, contamination with other metals can be suppressed, thereby improving recovery efficiency.

[0067] (Configuration 2) The method for treating a battery according to Configuration 1, wherein the deactivation step deactivates the contents of the target battery by placing the contents of the target battery in a treatment environment containing water vapor. According to the battery treatment method of the second aspect, conditions that promote sulfurization of the copper component contained in the target battery can be easily realized.

[0068] (Configuration 3) The method for treating a battery according to Configuration 1 or 2, wherein in the recovery step, the tail separated from the solid matter in the flotation step is dried to recover the positive electrode active material. According to the battery treatment method of the third aspect, the positive electrode active material containing at least one of nickel, cobalt, and manganese can be easily recovered.

[0069] (Configuration 4) The method for treating batteries according to any one of Configurations 1 to 3, wherein in the flotation step, the solid matter is removed by flotation by adding a collector and a foaming agent to the slurry. According to the battery treatment method of the fourth aspect, by removing solid matter in the flotation step, copper components can be efficiently separated from the slurry containing the positive electrode active material.

[0070] (Configuration 5) The method for treating a battery according to any one of Configurations 1 to 4, wherein the copper member is a copper foil that constitutes the negative electrode. According to the battery treatment method of configuration 5, when recovering a positive electrode active material from a target battery that uses copper foil as a negative electrode, contamination with components derived from the copper foil can be suppressed, thereby improving recovery efficiency. [Explanation of symbols]

[0071] 2...flotation 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 material, 32...positive electrode composite, 42...negative electrode composite.

Claims

1. A method for treating a battery, the target battery being an all-solid-state battery configured using copper members, the all-solid-state battery including a positive electrode having a positive electrode composite including a positive electrode active material, a negative electrode, and a sulfide-based solid electrolyte, the all-solid-state battery comprising: a deactivation step of deactivating the contents of the target battery under conditions that promote a sulfurization reaction of the copper member; a separation step of separating the positive electrode mixture from the material constituting the positive electrode; a treatment step of forming a slurry containing the positive electrode mixture separated in the separation step; a flotation step of removing solid matter derived from the copper members from the slurry by flotation; a recovery step of recovering the positive electrode active material from the slurry from which the solid matter has been removed in the flotation step; A method for treating a battery, comprising:

2. The battery treatment method according to claim 1 , wherein the deactivation step deactivates the contents of the target battery by placing the contents of the target battery in a treatment environment containing water vapor.

3. The battery treatment method according to claim 1 , wherein in the recovery step, the positive electrode active material is recovered by drying the tail separated from the solid matter in the flotation step.

4. 4. The method for treating batteries according to claim 1, wherein the solid matter is removed by flotation by adding a collector and a foaming agent to the slurry in the flotation step.

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

Images