Battery processing method

Abstract

The present invention makes it possible to efficiently recover valuable metal, including nickel, cobalt, or manganese, from a used secondary battery.　A battery processing method according to the present invention is for processing a lithium ion battery or an all-solid battery that includes an electrode material that includes at least one of nickel, cobalt, and manganese. The battery processing method includes a deactivation step for deactivating the contents of the battery at 80°C or below, a separation step for adding water to the deactivated contents to extract the electrode material, and a magnetic separation step for using an electromagnet to recover the electrode material.

Description

Battery disposal method

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

[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 composite of these 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 used lithium ion batteries are crushed and water is added to form a suspension slurry, and NCM contained in the suspension slurry is selectively separated and recovered by magnetic attraction.

[0004] Japanese Patent Application Laid-Open No. 2020-129505

[0005] However, in technologies related to secondary batteries, a challenge is to recover valuable metals more efficiently. For example, in the method disclosed in Patent Document 1, prior to the crushing process of used lithium-ion batteries, the lithium-ion batteries are subjected to a heat treatment by heating them to a temperature of 400°C to 600°C, thereby thermally decomposing the flammable electrolyte and rendering it harmless, and also thermally decomposing combustible materials such as separators and adhesive resins to reduce their volume. The heat treatment then converts the NCM into nickel oxide or cobalt oxide, which can be recovered using a magnetic field of approximately 1000 to 8000 gauss, which can be achieved using a permanent magnet.

[0006] However, when the valuable metals to be recovered are converted into nickel oxide or cobalt oxide as in the method described in Patent Document 1, the recovered metal oxides must be reduced for reuse. Furthermore, manganese is not oxidized by the heat treatment described above, so it must be recovered in a process separate from that for nickel and cobalt. Therefore, a method for more efficiently recovering valuable metals, including nickel, cobalt, or manganese, from used secondary batteries has been desired. In order to solve the above problems, the present application aims to efficiently recover valuable metals, including nickel, cobalt, or manganese, from used secondary batteries. This, in turn, contributes to energy efficiency.

[0007] One aspect of the present disclosure is a method for treating a battery, the target battery being a lithium-ion battery or an all-solid-state battery having an electrode material containing one or more of nickel, cobalt, and manganese, the method including: a deactivation step of deactivating the contents of the target battery at a temperature of 80°C or less; a separation step of adding water to the deactivated contents to extract the electrode material; and a magnetic separation step of recovering the electrode material using an electromagnet.

[0008] According to one aspect of the present disclosure, valuable metals including nickel, cobalt, or manganese can be more efficiently recovered from used secondary batteries.

[0009] 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. FIG. 2 is a diagram showing a battery processing method. FIG. 3 is a diagram showing an example of the configuration of a magnetic separator. FIG. 4 is a chart showing the correlation between the magnetic flux density of the magnetic separator in the magnetic separation process and the recovery rate of valuable metals. FIG. 5 is a chart showing the correlation between the concentration of the slurry in the magnetic separation process and the recovery rate of valuable metals. FIG. 6 is a chart showing the correlation between the number of repetitions of the magnetic separation process, the concentration and amount of the slurry, and the amount of valuable metals recovered. FIG. 7 is a chart showing the correlation between the concentration of the slurry in the magnetic separation process and the residual rate of impurities.

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] 1. Configuration of Target Battery 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.

[0012] The subject battery 10 is a secondary battery known as a lithium-ion battery, which has attracted attention as a high-energy-density power storage device. Examples of the positive electrode active material for a lithium-ion battery include lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, and lithium iron phosphate. Examples of the positive electrode active material include ternary cathode materials (NCMs) containing nickel, cobalt, and manganese. Examples of the negative electrode active material for a lithium-ion battery include carbon-based materials. All-solid-state batteries using a solid electrolyte as the electrolyte for a lithium-ion battery are also known.

[0013] 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.

[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 in 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 and prevents 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 plate-shaped positive electrode collector 31, and a positive electrode composite 32 is provided on both sides of the positive electrode collector 31. The positive electrode 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 that make up 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 that faces the positive electrode plate 11. The negative electrode current collector 41 is made of, for example, copper foil. 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, 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] When the target battery 10 is a lithium ion battery, the inside of the laminate material 22 is filled with a liquid or gel electrolyte. The electrolyte contains, for example, an electrolyte, a solvent, and an additive. The electrolyte is preferably lithium hexafluorophosphate (LiPF ６ Examples of the solvent and additive include carbonate esters such as ethylene carbonate, dimethyl carbonate, diethyl carbonate, and vinylene carbonate. These are just some examples, and the electrolyte, solvent, and additive can be selected and changed as appropriate.

[0022] When the target battery 10 is an all-solid-state battery, a solid electrolyte is disposed inside the laminate material 22. Although oxide-based electrolytes and sulfide-based electrolytes are known as solid electrolytes, the present disclosure may also be applicable to all-solid-state batteries using other materials. The solid electrolyte of the all-solid-state battery 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.

[0023] 2 is a diagram showing a battery processing method. In the cutting step S1, a part of the laminate material 22 constituting the outer casing is cut open to make the stacked electrode 21 accessible from the outside. If the target battery 10 contains a liquid or gel electrolyte, the electrolyte is drained from the cut portion in the cutting step S1.

[0024] In the deactivation step S2, the contents of the laminate material 22 are deactivated using water. The contents of the laminate material 22 refer to the material constituting the laminate electrode 21 and may include the current collector tabs 23A and 23B. In the deactivation step S2, the cut target battery 10 is deactivated using water or steam. The temperature of the water or steam used in the deactivation step S2 is preferably a temperature that does not oxidize the nickel, cobalt, and manganese contained in the target battery 10. A particularly preferred temperature is 80°C or less. In the deactivation step S2, the nickel, cobalt, and manganese contained in the target battery 10 can be treated without high-temperature heat treatment without causing any changes in their material morphology. When using steam in the deactivation step S2, it is possible to place the contents of the target battery 10 in a high-humidity environment. However, setting the temperature of this environment to 80°C or less ensures that the amount of water vapor in the air in a high-humidity environment is appropriate. Therefore, by setting the temperature of the deactivation step S2 to 80° C. or less, the contents of the target battery 10 can be deactivated without causing problems caused by, for example, an excessive amount of water vapor.

[0025] In the deactivation step S2, for example, the target battery 10 that was cut in the cutting step S1 is subjected to treatment such as immersing the target battery 10 in water, pouring water onto the target battery 10, spraying water vapor onto the target battery 10, or filling the container or chamber that houses the target battery 10 with water vapor.

[0026] In the deactivation step S2, at least a portion of the lithium contained in the contents of the target battery 10 is converted into a lithium compound such as lithium hydroxide, which becomes easily soluble in water. In addition, in the deactivation step S2, ventilation, intake and exhaust, neutralization treatment, etc. may be performed in response to the generation of hydrogen sulfide or other gases.

[0027] After the deactivation step S2, a separation step S3 is performed. The separation step S3 is a step of separating components rich in nickel, cobalt, and manganese, which are valuable metals to be recovered, from the contents of the target battery 10. The separation step S3 includes a crushing step S31, an extraction step S32, a sieving step S33, a copper recovery step S34, a filtration step S35, a water dissolving step S36, a peeling step S37, and a filtration step S38. The crushing step S31 corresponds to an example of a cutting step.

[0028] In the shredding step S31, the target battery 10 is shredded or cut using a shredder or other cutting device. In the shredding step S31, for example, the entire target battery 10 including the laminate material 22 is shredded using the cutting device. The pieces of the target battery 10 shredded in the shredding step S31 are called shredded material.

[0029] In the cutting step S1 or the deactivation step S2, a process may be performed to remove the contents of the target battery 10 from the laminate material 22. In this case, in the separation step S3, the contents of the target battery 10 removed from the laminate material 22 are crushed or cut. When this method is employed, aluminum derived from the laminate material 22 is not mixed into the crushed material, and therefore the NCM can be recovered more efficiently.

[0030] In the extraction step S32, the water-soluble components contained in the crushed material are dissolved in water. In the extraction step S32, the crushed material is exposed to a sufficient amount of water by, for example, immersing or immersing the crushed material in water, or by washing the crushed material with water. This causes the water-soluble components contained in the contents of the target battery 10 to elute into the water. In the extraction step S32, the deactivated lithium compound, electrolyte, or solid electrolyte dissolves in the water, making the water strongly alkaline.

[0031] In the sieving step S33, the mixture containing the water and crushed material used in the extraction step S32 is sieved to collect solid matter larger than the mesh size of the sieve. The material that passes through the sieve is called the permeate, and corresponds to the mixture obtained in the extraction step S32 after removing the large solid matter. Examples of solid matter removed by the sieve include the aluminum plate or aluminum foil used in the positive electrode current collector 31 and the copper foil used in the negative electrode current collector 41. Furthermore, when the target battery 10 with the laminate material 22 attached is crushed in the crushing step S31, the solid matter removed in the sieving step S33 includes fragments of the laminate material 22.

[0032] The solid matter collected in the sieving step S33 is treated in a copper recovery step S34. In the copper recovery step S34, copper is recovered from the solid matter collected in the sieving step S33. The remainder after copper recovery contains aluminum and NCM that has adhered to the surface of the solid matter.

[0033] Meanwhile, the permeate from the sieving step S33 is filtered in a filtration step S35. In the filtration step S35, the permeate is filtered using a filter material with a finer mesh than that used in the sieving step S33, and solids contained in the permeate are collected. The solids collected in the filtration step S35 include fine particles, such as particles containing a solid electrolyte and an NCM.

[0034] Lithium is recovered from the liquid that has passed through the filter in the filtration step S35 in a step not shown in Fig. 2. For the recovery of lithium, a known method such as the Li Separation Method by Ionic Conductor (LiSMIC) can be used.

[0035] The solids collected by the filter medium in the filtration step S35 and the remainder from which copper has been removed in the copper recovery step S34 are mixed with water and stirred in the water dissolving step S36. The water dissolving step S36 is a treatment in which water is added to the solids and water-soluble components are dissolved.

[0036] After the water dissolving step S36, the mixture of water and solids is treated in a peeling step S37. The peeling step S37 is a process in which the solids in the water are impacted to break them into smaller particles and further peel off the NCM attached to the solids. By the peeling step S37, a slurry containing water, NCM, aluminum, and a trace amount of copper is formed.

[0037] The slurry that has been treated in the water dissolving step S36 is filtered in the filtration step S38. In the filtration step S38, a filter medium is used that is large enough to allow the NCM to pass through and capture larger pieces of aluminum foil or aluminum plate. This allows the aluminum pieces used in the target battery 10 to be recovered, and a slurry containing a large amount of NCM is obtained.

[0038] In this manner, in the separation step S3, a slurry containing NCM is obtained from the target battery 10 deactivated in the deactivation step S2.

[0039] In the magnetic separation step S4, the slurry produced in the separation step S3 is processed by a magnetic separator, and the NCM particles are magnetically collected. The magnetic separator is equipped with a magnetic filter, and the NCM are magnetically collected by passing the slurry through this filter. As an example of a device used in the magnetic separation step S4, a magnetic separator 50 will be described.

[0040] 3 is a diagram showing an example of the configuration of a magnetic separator 50. The magnetic separator 50 includes a collection unit 51 that magnetically collects NCMs, and a collection tube 52 that passes through the collection unit 51. The collection unit 51 is an electromagnet having a pair of coils 54 and 55, which are arranged to sandwich the collection tube 52. A collection filter 53 is arranged between the coils 54 and 55.

[0041] The collection filter 53 is formed by laminating, for example, plate-shaped stainless steel meshes. The collection filter 53 is fixed inside the collection tube 52 and is arranged so that the fluid flowing through the collection tube 52 passes through the collection filter 53.

[0042] The collection tube 52 is a hollow tube through which a liquid containing NCM flows. The cross-sectional shape of the collection tube 52 is not limited to a specific shape as long as it corresponds to the shape of the collection filter 53. For example, a rectangular parallelepiped collection filter 53 may be housed in the collection tube 52 made of a square tube.

[0043] The fluid to be treated in the magnetic separator 50 flows in through an inlet 52A at the upper end of the collection tube 52. In this embodiment, the slurry that has undergone the separation step S3 flows into the inlet 52A, flows downward inside the collection tube 52, and is discharged from an outlet 52B at the lower end of the collection tube 52.

[0044] An adjustment unit 56 is disposed below the collection tube 52. The adjustment unit 56 is, for example, a valve that opens and closes the collection tube 52 and can adjust the opening degree. The adjustment unit 56 can adjust the flow rate of the fluid flowing through the collection tube 52. By adjusting the flow rate with the adjustment unit 56, the flow velocity of the fluid flowing through the collection tube 52 can be adjusted. In other words, the adjustment unit 56 functions as a flow velocity adjustment device that adjusts the flow velocity of the fluid passing through the collection filter 53.

[0045] The magnetic separator 50 is installed, for example, so that the collection pipe 52 faces up and down. That is, the inlet 52A is located higher than the outlet 52B, and the slurry flows down inside the collection pipe 52 by gravity.

[0046] The collection unit 51 generates a magnetic force corresponding to the current flowing through the coils 54 and 55, magnetizing the collection filter 53. As a result, magnetic material contained in the fluid passing through the collection filter 53 is magnetically attached to the collection filter 53. After a predetermined amount of fluid has flowed through the collection filter 53, the current flowing through the collection unit 51 is turned off and a solvent such as water is flowed through the collection tube 52, causing the magnetic material adhering to the collection filter 53 to be washed away by the solvent and collected.

[0047] 2, the NCM contained in the slurry is collected by, for example, a magnetic separator 50. The slurry treated in the magnetic separation step S4 is the slurry from which most of the components other than NCM have been separated in the separation step S3, and therefore, it is possible to efficiently recover NCM with high purity in the magnetic separation step S4.

[0048] The NCM can be recovered by dehydrating and drying the material collected in the magnetic separation step S4. The water separated by dehydration can be reused as water to be added in the water dissolving step S36.

[0049] The inventors have found that the conditions under which the magnetic separation step S4 is performed affect the recovery rate and the purity of the recovered NCM in the magnetic separation step S4. Specifically, the conditions under which the magnetic separation step S4 is performed include the magnetic force of the collection unit 51, the flow rate of the slurry flowing through the collection filter 53, and the concentration of NCM contained in the slurry. The inventors have found suitable conditions for the magnetic separation step S4, which will be described below.

[0050] 4 is a diagram showing the correlation between the magnetic flux density of the magnetic separator 50 and the recovery rate of valuable metals. In FIG. 4, the horizontal axis represents the magnetic flux density in the collection filter 53, and the unit of the values ​​on the horizontal axis is T (tesla). The vertical axis represents the recovery rate of NCM by the magnetic separator 50, and the unit of the values ​​on the vertical axis is %. In this embodiment, "%" represents % by mass.

[0051] Figure 4(a) shows the correlation between magnetic flux density and recovery rate when the slurry flow rate is 0.59 m / min. Figure 4(b) shows the correlation between magnetic flux density and recovery rate when the slurry flow rate is 2.43 m / min. Figure 4(c) shows the correlation between magnetic flux density and recovery rate when the slurry flow rate is 5.65 m / min. In Figures 4(a) to 4(c), the concentration of NCM in the slurry is 50 g / L.

[0052] From Figure 4, it can be seen that the lower the flow rate, the higher the NCM recovery rate tends to be. It can also be seen that the higher the magnetic flux density, the higher the NCM recovery rate tends to be. When the magnetic flux density is 1.8 T, the recovery rate exceeds 80% regardless of the flow rate. Even when the magnetic flux density is 0.8 T, a recovery rate exceeding 90% is obtained in Figures 4(a) and 4(b). Therefore, it can be said that the magnetic flux density of the magnetic separator 50 is preferably 0.8 T or higher, and most preferably 1.8 T or higher.

[0053] 5 is a diagram showing the correlation between the concentration of the slurry and the recovery rate of valuable metals. In FIG. 5, the horizontal axis represents the concentration of NCM in the slurry, and the units of the values ​​on the horizontal axis are g / L. The vertical axis represents the recovery rate of NCM by the magnetic separator 50, and the units of the values ​​on the vertical axis are %.

[0054] Figure 5(a) shows the correlation between concentration and recovery rate when the slurry flow rate is 0.59 m / min. Figure 5(b) shows the correlation between concentration and recovery rate when the slurry flow rate is 2.43 m / min. Figure 5(c) shows the correlation between concentration and recovery rate when the slurry flow rate is 5.65 m / min. Figures 5(a) to 5(c) plot the range of values ​​and their median values ​​when experiments are performed multiple times under the same conditions. In Figures 5(a) to 5(c), the magnetic flux density of the magnetic separator 50 is 1.8 T.

[0055] As shown in Figure 5, when the concentration of NCM is 100 g / L, a recovery rate of over 90% is obtained in Figure 5(a) and Figure 5(b), and when the concentration of NCM is 50 g / L, a recovery rate of over 95% is obtained in Figure 5(a) and Figure 5(b).

[0056] From the above, it can be said that the lower the NCM concentration in the slurry, the higher the NCM recovery rate tends to be. In addition, the lower the NCM concentration, the smaller the variation in values, which means that NCM can be recovered stably at a high recovery rate.

[0057] Regarding the flow velocity of the slurry, it can be said that the lower the flow velocity, the higher the NCM recovery rate tends to be. This is because, when the flow velocity is low, the NCM stays inside the collection filter 53 for a long time, and more NCM is magnetically attached to the collection filter 53. Therefore, from the viewpoint of increasing the recovery rate, it can be said that the lower the flow velocity of the slurry, the better the results obtained. However, under conditions in which the NCM stays inside the collection filter 53 for a long time, substances other than NCM, i.e., substances considered to be impurities, also stay inside the collection filter 53 for a long time, and more impurities are recovered by adhering to the NCM. Therefore, from the viewpoint of the purity of the recovered NCM, a higher flow velocity is preferable.

[0058] For this reason, it can be said that the concentration of NCM in the slurry is preferably 100 g / L or less, more preferably 50 g / L or less, and most preferably 50 g / L. When the concentration of NCM in the slurry is 50 g / L or less, a high recovery rate can be obtained even when the flow rate of the slurry is 5.65 m / min or 2.43 m / min, and the recovered NCM can be expected to have a high purity.

[0059] Considering these factors comprehensively, the flow rate of the slurry is preferably 2.43 m / min or more, and in this case, it is more preferable that the NCM concentration in the slurry is 50 g / L or less. A more preferable flow rate is 5.65 m / min or more, and in this case, it is even more preferable that the NCM concentration in the slurry is 50 g / L or less. The most preferable conditions are a flow rate of 5.65 m / min or more and an NCM concentration in the slurry of 50 g / L.

[0060] FIG. 6 is a chart showing the correlation between the number of repetitions of the magnetic separation step and the amount of valuable metals recovered. In FIG. 6, the horizontal axis represents the number of repetitions (number of passes) of the magnetic separation step S4. The number of repetitions of the magnetic separation step S4 is the number of times the slurry is passed through the collection tube 52, and one pass is defined as a single pass of the slurry. Furthermore, if the slurry discharged from the outlet 52B is reintroduced into the inlet 52A, causing the slurry to be passed through the collection tube 52 twice, the number of passes is two. Similarly, if the slurry is passed through the collection tube 52 three times, the number of passes is three. For reference, the leftmost side of the horizontal axis shows the numerical value of the sample before the magnetic separation step S4, i.e., the initial slurry concentration.

[0061] The vertical axis of Fig. 6 indicates the recovery rate of NCM by the magnetic separator 50, and the numerical values ​​on the vertical axis are in %. Fig. 6(a) shows the correlation between the number of passes and the recovery rate when the NCM concentration in the slurry is 20 g / L. Fig. 6(b) shows the correlation between the number of passes and the recovery rate when the NCM concentration in the slurry is 50 g / L. In Fig. 6, the magnetic flux density of the magnetic separator 50 is 1.8 T.

[0062] 6(a) and 6(b), it can be seen that the correlation between the number of passes and the recovery rate tends to be higher as the number of passes increases. The recovery rate also increases as the slurry concentration increases, with the best results being obtained in the example where the NCM concentration in the slurry was 50 g / L (FIG. 6(b)).

[0063] Therefore, the conditions for the magnetic separation step S4 are that the concentration of NCM in the slurry is 50 g / L or more and the number of passes is 3 or more.

[0064] Figure 7 is a diagram showing the correlation between the concentration of the slurry and the residual rate of impurities. In Figure 7, the horizontal axis shows the concentration of the slurry used in the test in g / L. The vertical axis shows the residual rate of impurities in mass %.

[0065] Here, the residual rate of impurities refers to the proportion of impurities contained in the material recovered by the magnetic separator 50 when a slurry of a predetermined concentration is treated in one pass by the magnetic separator 50. In detail, when the mass of impurities contained in the slurry before treatment by the magnetic separator 50, i.e., the initial amount of impurities, is defined as MCS, and the amount of impurities contained in the material when the number of passes is one is defined as MC, the residual rate R can be calculated by the following formula (1): R=MC / MCS [%] (1)

[0066] 7 shows the results of a test using a combination of aluminum and copper sulfide as an index of impurities, but the impurities used in the actual treatment of the target battery 10 include copper sulfide such as CuS, CuS, and copper sulfides of other compositions. It is easy to imagine that copper sulfides of compositions other than CuS will also show a similar trend to that shown in FIG.

[0067] Plot A in FIG. 7 shows the results when the NCM concentration in the slurry (synonymous with the slurry concentration) was 10 g / L, where the initial impurity amount was 6.79 g and the impurity amount in the recovered product was 1.19 g. Plot B in FIG. 7 shows the results when the NCM concentration in the slurry was 20 g / L, where the initial impurity amount was 6.67 g and the impurity amount in the recovered product was 1.50 g. Plot C in FIG. 7 shows the results when the NCM concentration in the slurry was 50 g / L, where the initial impurity amount was 6.47 g and the impurity amount in the recovered product was 1.90 g. Plot D in FIG. 7 shows the results when the NCM concentration in the slurry was 100 g / L, where the initial impurity amount was 6.19 g and the impurity amount in the recovered product was 2.09 g.

[0068] The results in Figure 7 clearly show that the lower the concentration of the slurry, the less impurities are mixed into the recovered material. Figure 7 shows the residual rate when the number of passes is set to 1, but for example, in the second pass and thereafter, the slurry concentration is low because most of the NCM in the slurry is recovered in the first pass. For this reason, it can be said that the residual rate of impurities in the second pass and thereafter is significantly lower than the value shown in Figure 7.

[0069] 6 and 7, it was revealed that in the magnetic separation step S4, a lower slurry concentration can reduce the amount of impurities, but the lower the slurry concentration, the lower the NCM recovery rate. For example, from the viewpoint of the impurity residual rate, the NCM concentration in the slurry is preferably 50 g / L or less, and from the viewpoint of the NCM recovery rate, the NCM concentration in the slurry is preferably 50 g / L or more. Therefore, a preferable condition that can achieve both a high NCM recovery rate and a low impurity contamination rate is to set the NCM concentration in the slurry to 50 g / L.

[0070] As described above, the method for treating the target battery 10 described in this embodiment is a method for treating a battery in which the target battery is a lithium-ion battery or an all-solid-state battery having an electrode material containing one or more of nickel, cobalt, and manganese. This treatment method includes a deactivation step S2 in which the contents of the target battery are deactivated at a temperature of 80° C. or less, a separation step S3 in which water is added to the deactivated contents to extract the electrode material, and a magnetic separation step S4 in which the electrode material is recovered using an electromagnet.

[0071] This method allows nickel, cobalt, and manganese to be recovered from lithium-ion batteries and all-solid-state batteries without high-temperature heat treatment and without causing any change in the material morphology, thereby enabling more efficient recovery of valuable metals from used lithium-ion batteries and all-solid-state batteries.

[0072] In the above-described battery processing method, the magnetic flux density of the magnetic separator 50 may be set to 1.8 T or higher in the magnetic separation step S4. This allows nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries to be recovered by magnetic attraction without being subjected to high-temperature heat treatment. This allows valuable metals to be recovered more efficiently from used batteries.

[0073] In the above-described battery treatment method, in the magnetic separation step S4, a slurry containing the electrode material may be passed through a magnetic separator 50 to recover the electrode material, and the flow rate of the slurry flowing through the magnetic separator 50 may be set to 2.43 m / min or more. This allows nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries to be recovered by magnetic attraction under conditions that can suppress the incorporation of impurities. This allows valuable metals to be recovered more efficiently from used batteries.

[0074] In the battery treatment method, the concentration of the electrode material contained in the slurry may be 50 g / L or less. This allows nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries to be recovered by magnetic attraction with high efficiency under conditions that can suppress the incorporation of impurities. This allows for more efficient recovery of valuable metals from used batteries.

[0075] In the above-described battery treatment method, in the magnetic separation step S4, a slurry containing the electrode material may be passed through a magnetic separator 50 to recover the electrode material, and the flow rate of the slurry flowing through the magnetic separator 50 may be set to 5.65 m / min or more. This allows nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries to be recovered by magnetic attraction under conditions that more reliably suppress the incorporation of impurities. This allows valuable metals to be recovered more efficiently from used batteries.

[0076] In the battery treatment method, the concentration of the electrode material contained in the slurry may be 50 g / L or less. This allows nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries to be recovered by magnetic attraction with high efficiency under conditions that more reliably suppress the inclusion of impurities. This allows for more efficient recovery of valuable metals from used batteries.

[0077] In the battery treatment method, the concentration of the electrode material contained in the slurry may be 50 g / L. This allows nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries to be recovered by magnetic attraction with high efficiency under conditions that more reliably suppress the inclusion of impurities. In other words, it is possible to achieve both a high recovery rate of NCM in the magnetic separation step S4 and the suppression of impurity inclusion. This allows for more efficient recovery of valuable metals from used batteries.

[0078] In the above-described battery treatment method, the slurry may be passed through the magnetic separator 50 two or more times in the magnetic separation step S4. This allows nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries to be recovered more efficiently by magnetic attraction. This allows valuable metals to be recovered more efficiently from used batteries.

[0079] The battery treatment method includes a cutting step S1 for opening the exterior of the target battery, and a deactivation step S2 for deactivating the contents exposed from the exterior in the cutting step S1 by adding steam or water at 80°C or less to the contents. This allows the contents of the battery to be deactivated without causing changes in the material morphology of nickel, cobalt, and manganese when recovering valuable metals from lithium-ion batteries or all-solid-state batteries. This allows for more efficient recovery of valuable metals from used lithium-ion batteries or all-solid-state batteries.

[0080] The battery treatment method may include a crushing step S31, an extraction step S32, a sieving step S33, and a peeling step S37. The crushing step S31 involves cutting the contents deactivated in the deactivation step S2. The extraction step S32 involves removing electrolyte from the contents cut in the crushing step S31. The sieving step S33 involves sieving the contents after the extraction step S32. The peeling step S37 involves peeling impurities from the material that passed through the sieve in the sieving step S33. The electrode material that has undergone the peeling step S37 may then be recovered in a magnetic separation step S4. This allows valuable metals, including nickel, cobalt, or manganese, to be more efficiently recovered from lithium-ion batteries and all-solid-state batteries.

[0081] Examples of the present invention will be described in detail below, but the present invention should not be construed as being limited based on the description of these examples.

[0082] Example 1 In Example 1, the correlation between the magnetic flux density of the magnetic separator 50 and the recovery rate of valuable metals was investigated. In preparing the samples, a ternary positive electrode material used in lithium ion batteries and all-solid-state batteries was used as the positive electrode active material.

[0083] In Example 1, the positive electrode active material was granulated and dispersed in water, and 1 L of slurry (1 L = 10 －３ m ３ A sample containing 50 g of the positive electrode active material in a 1 L battery was prepared.

[0084] As a condition of the magnetic separator 50 in Example 1, the flow velocity of the slurry flowing through the collection pipe 52 was set to three levels: 0.59 m / min, 2.43 m / min, and 5.65 m / min.

[0085] The flow rate of the slurry is a value obtained by measuring the amount of slurry discharged from the outlet 52B per unit time, calculating the amount of slurry per minute from the measured value, and dividing the calculated amount by the cross-sectional area of ​​the collection tube 52 in the collection filter 53. This also applies to each of the examples described below.

[0086] In Example 1, the magnetic flux density in the collection filter 53 was used as an index of the magnetic force of the collection unit 51, and was given three values: 0 T, 0.8 T, and 1.8 T. The magnetic flux density in the collection filter 53 may be an actually measured value, but in this example, the magnetic separator 50 was operated with a current when 0.8 T was measured in a test of the magnetic separator 50, and this was considered to be the condition for a magnetic flux density of 0.8 T. The same applies to a magnetic flux density of 1.8 T. Furthermore, the magnetic flux density when no current is flowing through the coils 54 and 55 was taken as 0 T.

[0087] The sample prepared by the above procedure was passed through the collection tube 52 with current flowing through the coils 54 and 55 of the collection unit 51, thereby collecting the NCM in the slurry. Thereafter, with the current to the coils 54 and 55 turned off, water for collection was flowed through the collection unit 51, and the NCM that flowed out from the outlet 52B together with the water was collected by filtration. The amount of water used for collection was 0.5 L. The collected NCM was dehydrated and dried, and its weight was measured, and the measured weight was used as the amount of collected NCM.

[0088] The recovery rate of NCM was evaluated by first calculating the weight of NCM in the slurry passed through the magnetic separator 50 as a target weight, and then determining the ratio of the recovery amount to the target weight. The target weight was calculated from the concentration of NCM in the slurry and the amount of slurry passed through the magnetic separator 50. The results of Example 1 are shown in FIG. 4.

[0089] [Example 2] In Example 2, the correlation between the concentration of the slurry and the recovery rate of valuable metals was investigated. As samples for Example 2, slurries containing positive electrode active material were prepared in the same manner as in Example 1. A sample containing 150 g of positive electrode active material in 1 L of slurry, a sample containing 100 g of positive electrode active material in 1 L of slurry, and a sample containing 50 g of positive electrode active material in 1 L of slurry were prepared. The amount of each sample used in the experiment was 1 L.

[0090] In Example 2, similarly to Example 1, the flow velocity of the slurry flowing through the collection pipe 52 was set to three different flow velocities: 0.59 m / min, 2.43 m / min, and 5.65 m / min. Also, in Example 2, the magnetic flux density in the collection filter 53 was set to 1.8 T. The flow velocity of the slurry and the magnetic flux density of the collection filter 53 were values ​​obtained similarly to Example 1.

[0091] The recovery rate of NCM was evaluated using the same method as in Example 1. The results of Example 2 are shown in FIG.

[0092] Example 3 In Example 3, the correlation between the number of repetitions of the magnetic separation step and the amount of impurities mixed in and the amount of valuable metals recovered was investigated.

[0093] For the sample of Example 3, a slurry containing a positive electrode active material was prepared using the same method as in Example 1, except that the positive electrode active material added to water was artificially mixed with aluminum particles and copper sulfide to simulate impurities. Using this mixture of the positive electrode active material, aluminum particles, and copper sulfide, a sample containing 100 g of the mixture in 1 L of slurry, a sample containing 50 g of the mixture in 1 L of slurry, a sample containing 20 g of the mixture in 1 L of slurry, and a sample containing 10 g of the mixture in 1 L of slurry were prepared. In Example 3, the flow rate of the slurry flowing through the collection tube 52 was 5.65 m / min, and the magnetic flux density at the collection filter 53 was 1.8 T. The flow rate of the slurry and the magnetic flux density at the collection filter 53 were values ​​obtained in the same manner as in Example 1.

[0094] In Example 3, when the magnetic separation step was repeated, the sample was introduced into the inlet 52A, the sample discharged from the outlet 52B was collected, and the collected sample was introduced into the inlet 52A again. This operation was repeated the number of times described above.

[0095] The recovery rate of NCM was evaluated using the same method as in Example 1. The impurity contamination rate in the recovered NCM was evaluated using ICP atomic emission spectroscopy. The initial impurity contamination rate shown in Figure 6 is the contamination rate of aluminum and copper sulfide in the mixture added to water during slurry sample preparation. The results of Example 3 are as shown in Figures 6 and 7.

[0096] 4. Other Embodiments The above embodiment is merely one mode of carrying out the present invention, and any modifications and applications are possible without departing from the spirit of the present invention.

[0097] In the above embodiment, the magnetic separator 50 is exemplified, which has the collection tube 52 located between a pair of coils 54, 55 and is configured so that the slurry flows from top to bottom inside the collection tube 52. This is just one example, and there is no limitation on the device that can be used in the magnetic separation step S4.

[0098] Furthermore, the shape of the target 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 lithium ion batteries other than laminated batteries and all-solid-state batteries.

[0099] 5. Configurations Supported by the Above-described Embodiments The above-described embodiments support the following configurations.

[0100] (Configuration 1) A battery treatment method for a lithium-ion battery or an all-solid-state battery having an electrode material containing one or more of nickel, cobalt, and manganese, comprising: a deactivation step of deactivating the contents of the target battery at 80°C or below; a separation step of adding water to the deactivated contents to extract the electrode material; and a magnetic separation step of recovering the electrode material using an electromagnet. According to the battery treatment method of Configuration 1, nickel, cobalt, and manganese can be recovered from lithium-ion batteries or all-solid-state batteries by treating them without high-temperature heat treatment, without causing any change in the material morphology. This allows for more efficient recovery of valuable metals from used lithium-ion batteries or all-solid-state batteries.

[0101] (Configuration 2) The battery treatment method according to Configuration 1, wherein the magnetic flux density in the magnetic separation step is 1.8 T or more. According to the battery treatment method of Configuration 2, nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries can be recovered by magnetic attraction without being subjected to high-temperature heat treatment. This allows for more efficient recovery of valuable metals from used batteries.

[0102] (Configuration 3) The battery treatment method according to Configuration 1 or 2, wherein in the magnetic separation step, a slurry containing the electrode material is passed through a magnetic separator having an electromagnet to recover the electrode material, and the flow rate of the slurry flowing through the magnetic separator is set to 2.43 m / min or more. According to the battery treatment method of Configuration 3, nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries can be recovered by magnetic attraction under conditions that can suppress the incorporation of impurities. Therefore, valuable metals can be recovered more efficiently from used batteries.

[0103] (Configuration 4) The battery treatment method according to Configuration 3, wherein the concentration of the electrode material contained in the slurry is 50 g / L or less. According to the battery treatment method of Configuration 4, nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries can be recovered by magnetic attraction with high efficiency under conditions that can suppress the incorporation of impurities. Therefore, valuable metals can be recovered more efficiently from used batteries.

[0104] (Configuration 5) The battery treatment method according to Configuration 1 or 2, wherein in the magnetic separation step, a slurry containing the electrode material is passed through a magnetic separator having an electromagnet to recover the electrode material, and the flow rate of the slurry flowing through the magnetic separator is set to 5.65 m / min or more. According to the battery treatment method of Configuration 5, nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries can be recovered by magnetic attraction under conditions that more reliably suppress the incorporation of impurities. Therefore, valuable metals can be recovered more efficiently from used batteries.

[0105] (Configuration 6) The battery treatment method according to Configuration 5, wherein the concentration of the electrode material contained in the slurry is 50 g / L or less. According to the battery treatment method of Configuration 6, nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries can be recovered by magnetic attraction with high efficiency under conditions that more reliably suppress the incorporation of impurities. Therefore, valuable metals can be recovered more efficiently from used batteries.

[0106] (Configuration 7) The battery treatment method according to Configuration 5, wherein the concentration of the electrode material contained in the slurry is 50 g / L. According to the battery treatment method of Configuration 7, nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries can be recovered by magnetic attraction with high efficiency under conditions that more reliably suppress the inclusion of impurities. In other words, a high recovery rate of valuable metals can be achieved in the magnetic separation process while suppressing the inclusion of impurities. This allows for more efficient recovery of valuable metals from used batteries.

[0107] (Configuration 8) The battery treatment method according to any one of Configurations 3 to 7, wherein the slurry is passed through the magnetic separator two or more times in the magnetic separation step. According to the battery treatment method of Configuration 8, nickel, cobalt, or manganese contained in lithium-ion batteries or all-solid-state batteries can be recovered more efficiently by magnetic attraction. Therefore, valuable metals can be recovered more efficiently from used batteries.

[0108] (Configuration 9) The battery treatment method according to any one of Configurations 1 to 8, further comprising a cutting step of opening the exterior of the target battery, wherein the deactivation step deactivates the contents exposed from the exterior by adding steam or water at 80°C or less to the contents. According to the battery treatment method of Configuration 9, when recovering valuable metals from lithium-ion batteries or all-solid-state batteries, the contents of the battery can be deactivated without causing changes in the material morphology of nickel, cobalt, and manganese. Therefore, valuable metals can be recovered more efficiently from used lithium-ion batteries or all-solid-state batteries.

[0109] (Configuration 10) The battery treatment method according to Configuration 9, comprising: a cutting step of cutting the contents deactivated in the deactivation step; an extraction step of removing electrolyte from the cut contents; a sieving step of sieving the contents after the extraction step; and a peeling step of peeling impurities from the pass-through material that has passed through the sieve in the sieving step, wherein the electrode material that has undergone the peeling step is recovered in the magnetic separation step. According to the battery treatment method of Configuration 10, valuable metals including nickel, cobalt, or manganese can be more efficiently recovered from lithium-ion batteries and all-solid-state batteries.

[0110] 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, 50...magnetic separator, 51...collection section, 52...collection tube, 52A...inlet, 52B...outlet, 53...collection filter, 54, 55...coil, 56...adjustment section.

Claims

1. A method for treating batteries, the target batteries being lithium-ion batteries or all-solid-state batteries having electrode materials containing one or more of nickel, cobalt, and manganese, comprising: a deactivation step of deactivating the contents of the target batteries at a temperature of 80°C or less; a separation step of adding water to the deactivated contents to extract the electrode material; and a magnetic separation step of recovering the electrode material using an electromagnet.

2. The battery treatment method according to claim 1, wherein the magnetic flux density in the magnetic separation step is 1.8 T or more.

3. The battery treatment method according to claim 1, wherein in the magnetic separation step, the electrode material is recovered by flowing a slurry containing the electrode material through a magnetic separator having the electromagnet, and the flow rate of the slurry flowing through the magnetic separator is set to 2.43 m / min or more.

4. The method for treating a battery according to claim 3, wherein the concentration of the electrode material contained in the slurry is set to 50 g / L or less.

5. The battery treatment method according to claim 1, wherein in the magnetic separation step, the electrode material is recovered by flowing a slurry containing the electrode material through a magnetic separator having the electromagnet, and the flow rate of the slurry flowing through the magnetic separator is set to 5.65 m / min or more.

6. The method for treating a battery according to claim 5, wherein the concentration of the electrode material contained in the slurry is 50 g / L or less.

7. The method for treating a battery according to claim 5, wherein the concentration of the electrode material contained in the slurry is 50 g / L.

8. The battery treatment method according to any one of claims 3 to 7, wherein the slurry is passed through the magnetic separator two or more times in the magnetic separation step.

9. The method for treating a battery according to claim 1, further comprising a cutting step of opening the exterior of the target battery, wherein the deactivation step deactivates the contents exposed from the exterior by adding water vapor or water at 80°C or less to the contents.

10. A battery treatment method according to claim 9, comprising: a cutting step of cutting the contents deactivated in the deactivation step; an extraction step of removing electrolyte from the cut contents; a sieving step of sieving the contents after the extraction step; and a peeling step of peeling off impurities from the material that has passed through the sieve in the sieving step, wherein the electrode material that has undergone the peeling step is recovered in the magnetic separation step.

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