Method for recycling waste secondary battery electrode material

Abstract

One embodiment of the present invention provides a method for recycling a waste secondary battery electrode material by using galvanic corrosion. According to the present invention, lithium in waste secondary battery electrode material can be replenished through a simple method under room temperature and atmospheric pressure conditions, and thus waste secondary battery electrode material of various degrees of deterioration can be collected in a single distribution to facilitate the recycling of the waste secondary battery electrode material.

Description

Method for recycling electrode materials from waste secondary batteries

[0001] The present invention relates to a method for recycling waste secondary battery electrode materials, and more specifically, to a method for recycling waste secondary battery electrode materials using galvanic corrosion.

[0002] This study was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) with funding from the Ministry of Trade, Industry and Energy (20221B1010003B, Development of innovative technology for upcycling and remanufacturing waste anodes for low-carbon resource circulation).

[0003] This work was supported by the Korea Institute of Energy Technology Evaluation and Planning(KETEP) grant funded by the Korea government(MOTIE) (20221B1010003B, Integrated High-Quality Technology Development of Remanufacturing Spent Cathode for Low Carbon Resource Recirculation)

[0004] Due to the recent rapid growth of the electric vehicle market, the global waste battery processing market is expected to grow to approximately 20 trillion won by 2030, and in Korea, approximately 80,000 waste batteries are expected to be generated in 2029.

[0005] Currently, waste battery recycling primarily relies on processes to recover valuable metals. However, existing urban mining technologies suffer from high carbon emissions, very low profitability, high process costs, and low sales revenue from recovered metals, resulting in very low economic viability (approximately $6.7 / kWh in losses). Furthermore, secondary battery manufacturers are recently reducing the content of expensive metals like cobalt, which is expected to further deteriorate the economic viability of urban mining technologies.

[0006] Meanwhile, research is also being conducted on recovering cathode materials from spent batteries. One example discloses a method for recovering cathode active material from an aluminum current collector. However, the recovered cathode active material is deteriorated over hundreds to thousands of cycles due to various factors, making it unusable without additional treatment.

[0007] Therefore, to achieve self-sufficiency in battery materials, which are currently dependent on global market leadership and full imports, it is necessary to develop innovative recycling technologies that improve the problems of existing waste battery recycling processes.

[0008]

[0009] The present invention has been devised to solve the aforementioned problem, and one embodiment of the present invention provides a method for recycling waste secondary battery electrode materials by simply replenishing lithium to deteriorated electrode materials under room temperature and pressure.

[0010] The technical problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0011]

[0012] As a technical means for achieving the aforementioned technical task, one aspect of the present invention is,

[0013] (1) a step of preparing a lithium restoration solution by mixing a lithium salt and a solvent; and (2) a step of restoring lithium by immersing an electrode from which lithium has been lost in the prepared lithium restoration solution; wherein the electrode from which lithium has been lost is immersed in the lithium restoration solution while a current collector and a positive electrode active material formed on the current collector are formed. A method for recycling a waste secondary battery electrode material is provided.

[0014] It may be characterized by supplying electrons from the current collector to the positive electrode active material by galvanic corrosion between metals included in the current collector and the positive electrode active material.

[0015] The above current collector may be an aluminum current collector, and may be characterized by being in the form of any one of a film, a sheet, a foil, a net, a porous body, a foam, and a non-woven fabric.

[0016] The lithium salt of the above step (1) is LiBr, LiI, LiCl, LiF, LiPF6, LiBF4, LiBF6, LiB 10 Cl 10, LiSbF6, LiAsF6, LiSO3CF3, LiCF3SO3, LiC(SO2CF3)3, LiN(CF3SO2)2, LiN(C2F5SO2)2, LiClO4, LiAlO 4, It may be characterized by any one of LiNO3, LiOAc, LiSCN, (CF3SO2)2Nli, CH3SO3Li, CF3SO3Li, lithium chloroborane, lithium tetraphenylborate, and LiAlCl4.

[0017] The solvent of the above step (1) may be characterized by being any one of water, distilled water, acetonitrile, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethylmethyl carbonate (EMC) or methylethyl carbonate (MEC), methyl propionate (MP), fluoroethylene carbonate (FEC), fluorobenzene (FB), vinylene carbonate (VC), vinylethylene carbonate (VEC), phenylethylene carbonate (PhEC), propylmethyl carbonate (PMC), diethoxyethane (DEE), dimethoxyethane (DME), tetrahydrofuran (THF), γ-butyrolactone (GBL), and γ-valerolactone (GVL).

[0018] The lithium restoration solution of the above step (1) may be characterized by containing a lithium salt at a concentration of 0.05 M to 0.5 M.

[0019] The above step (2) may be characterized in that it is performed at a temperature of 15 to 80°C.

[0020] The above step (2) may be characterized in that it is performed at a pressure of 0.8 to 1.3 bar.

[0021] The above step (2) may be characterized by being performed for 0.5 to 72 hours.

[0022] The electrodes in which lithium is lost in the above step (2) may be characterized by being a plurality of electrodes each having a different degree of lithium loss.

[0023] It may be characterized by further including a step of washing and drying the electrode restored by the above step (2).

[0024] The above washing may be characterized by washing using dimethyl carbonate (DMC) or acetone.

[0025] The above cathode active materials are LCO(LiCoO2), NCM(Li[Ni,Co,Mn]O2), NCA(Li[Ni,Co,Al]O-2), LLNCMO(Li[Li,Ni,Co,Mn]O2), LMO(LiMn2O4), LTO(Li 14 Ti 15 O 12 ), LFP (LiFePO4), LMP (LiMnPO4) or LCP (LiCoPO4).

[0026]

[0027] According to an embodiment of the present invention, lithium can be supplemented to a waste secondary battery electrode material in a simple manner under room temperature and pressure conditions, thereby allowing waste secondary battery electrode materials with various degrees of deterioration to be collected into a single distribution, facilitating recycling of the waste secondary battery electrode material.

[0028] The effects of the present invention are not limited to the above-described effects, and should be understood to include all effects that can be inferred from the composition of the invention described in the description or claims of the present invention.

[0029]

[0030] Figure 1 is a schematic diagram showing the process of replenishing lithium to a waste secondary battery electrode material depending on the presence or absence of an aluminum current collector.

[0031] Figure 2 shows SEM images of P-NCM, D-NCM, and R-NCM according to one embodiment of the present invention.

[0032] Figure 3 is a graph showing the XRD analysis results of P-NCM, D-NCM, and R-NCM.

[0033] Figure 4 is a graph showing the results of elemental analysis using an inductively coupled plasma optical emission spectrometry (ICP-OES) device for positive electrode active material samples extracted from P-NCM, D-NCM, and R-NCM.

[0034] Figure 5 is a graph showing the results of evaluating electrochemical characteristics for a full cell, and is a graph showing the results of discharge capacity as the reaction time increases.

[0035] Figure 6 is a graph showing the voltage measurement results according to the capacity of P-NCM, D-NCM, and R-NCM.

[0036] Figure 7 is a graph showing the relative lithium content of two samples with different lithium distributions and the amount of restoration when lithium was restored.

[0037] Figure 8 is a graph showing the results of ICP analysis performed on P-NCM, D-NCM, and R-NCM with the aluminum collector removed.

[0038]

[0039] Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement them. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0040]

[0041] Comparative example: D-NCM preparation

[0042] After a stabilization cycle, a full cell composed of an NCM622 positive electrode and a graphite negative electrode was disassembled and washed in a glove box at a 75% discharge state to prepare D-NCM with lithium loss.

[0043]

[0044] Example: Preparation of R-NCM

[0045] The D-NCM electrode was immersed in a restoration solution containing 0.2 M LiBr in acetonitrile for 24 hours. After 24 hours, the electrode was washed with acetone and dimethyl carbonate and dried to prepare R-NCM.

[0046]

[0047] Reference example: P-NCM preparation

[0048] The NCM622 cathode was prepared as a P-NCM sample.

[0049]

[0050] Experimental Example 1: SEM Analysis of P-NCM, D-NCM, and R-NCM

[0051] Fig. 2 illustrates SEM images of P-NCM, D-NCM, and R-NCM according to one embodiment of the present invention. Referring to Fig. 2, it can be confirmed that the aluminum foil was etched due to galvanic corrosion after lithium was restored from the electrode where lithium had been lost.

[0052]

[0053] Experimental Example 2: XRD (X-ray diffraction) measurement

[0054] For the positive electrode active material samples extracted from the above examples, comparative examples, and reference examples, XRD analysis was performed using XRD equipment (X'Pert PRO Multi Purpose, PANalytical Co.). XRD analysis was performed under the conditions of Cu K α (λ = 1.5418 Å), 40 kV, and 40 mA. To confirm the structural characteristics of the positive electrode active material obtained under the above conditions, the results of X-ray diffraction analysis were observed. Figure 3 is a graph of the XRD analysis results of P-NCM, D-NCM, and R-NCM.

[0055] From Fig. 3, it can be confirmed that the XRD peak positions of D-NCM (comparative example), R-NCM (example), and P-NCM (reference example) are almost similar. However, while the peak of 18.5 degrees, which is the (003) plane of D-NCM, is located at a lower 2theta, it can be confirmed that the (003) plane of R-NCM has moved to a higher 2theta, similar to P-NCM. This is a phenomenon that occurs as lithium ions are inserted between the planes during the restoration process of the example, reducing the distance between the (003) planes.

[0056]

[0057] Experimental Example 3: Analysis of the restored electrode using ICP-OES

[0058] Figure 4 shows the results of elemental analysis using ICP-OES equipment on positive electrode active material samples extracted from the above examples, comparative examples, and reference examples. It was confirmed that the lithium content in the positive electrode active material of D-NCM (comparative example) was 0.837, while the lithium content in the positive electrode active material of R-NCM (example) was 1.087, and the lithium content in the positive electrode active material of P-NCM (reference example) was 1.045. Through this, it can be seen that the positive electrode active material of the examples is in a state where the lost lithium has been replenished.

[0059]

[0060] Experimental Example 4: Electrochemical Characteristics Evaluation

[0061] The electrochemical properties of the full cell were evaluated using a charge / discharge equipment (WBCS3000L, Wonatech). The measurements were performed under conditions of a voltage range of 4.2 to 2.5 V and a constant current density of 0.1 C.

[0062] As a result, graphs such as Figs. 5 and 6 were derived.

[0063] Specifically, according to Fig. 5, as the reaction time increases, the amount of lithium restored increases and the discharge capacity improves accordingly, but after 24 hours, the degree of anode corrosion increases and the discharge capacity decreases. Accordingly, the R-NCM of the example was allowed to react for 24 hours under the conditions of the example during lithium restoration, and as a result, it was confirmed that it exhibited electrochemical performance similar to that of P-NCM, as shown in Fig. 6.

[0064]

[0065] Experimental Example 5: Analysis of restoration of multiple electrodes with different degrees of lithium loss

[0066] Figure 7 is a graph showing the relative lithium content of two samples with different lithium distributions and the amount restored when lithium was restored. Referring to Figure 7, the relative contents of lithium lost in Samples 1 and 2 were 50% and 75%, respectively (upper left), but after lithium was restored, the relative lithium contents of restored Samples 1 and 2 were measured to be 95%, respectively (upper right). This confirms that although the degree of lithium loss differed in multiple electrodes from which lithium was lost, lithium was replenished to the initial state through the restoration reaction.

[0067]

[0068] Experimental Example 6: Analysis of the Comparative Example Restoration Electrode via ICP-OES

[0069] Figure 8 is a graph showing the results of ICP analysis performed on P-NCM, D-NCM, and R-NCM with the aluminum collector removed. When a lithium-loss electrode with the aluminum collector removed was restored using the same process, the lithium molar ratio was measured to be 0.797, while the original D-NCM was measured to be 0.868. This result can be seen as a result that galvanic corrosion occurred between the lithium-loss electrode and the aluminum collector, and lithium restoration was sufficiently progressed.

[0070]

[0071] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will readily appreciate that the present invention can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single entity may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined manner.

[0072] The scope of the present invention is indicated by the claims set forth below, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

[0073]

[0074] Hereinafter, the present invention will be described in more detail. However, the present invention may be implemented in various different forms, and the present invention is not limited to the embodiments described herein, but is defined only by the claims set forth below.

[0075] Additionally, the terminology used herein is solely for the purpose of describing specific embodiments and is not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. Throughout the specification of the present invention, the term "including" or "comprising" a component does not exclude other components, but rather implies the inclusion of other components, unless specifically stated otherwise.

[0076] Throughout the specification, when a part is said to be "connected (connected, contacted, or coupled)" to another part, this includes not only cases where it is "directly connected," but also cases where it is "indirectly connected" with another part in between. Furthermore, when a part is said to "include" a component, this does not exclude other components, but rather implies that it may include other components, unless otherwise specifically stated.

[0077] The terminology used in this specification is for the purpose of describing specific embodiments only and is not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise.

[0078]

[0079] Among the properties mentioned in this specification, properties whose results are affected by measurement temperature and / or measurement pressure are the results measured at room temperature and / or pressure, unless otherwise specifically stated.

[0080] The term "room temperature" means a natural temperature that has not been heated or cooled, and means, for example, a temperature within the range of 10°C to 30°C, or a temperature of about 23°C or about 25°C. In addition, the unit of temperature in this specification is ℃ unless otherwise specified.

[0081] The term atmospheric pressure refers to the natural pressure that is neither pressurized nor depressurized, and usually means about 1 atmosphere, which is the level of atmospheric pressure.

[0082] In the present specification, for properties where the measured humidity affects the results, unless otherwise specified, the properties are properties measured at natural humidity that is not specifically controlled at the above-mentioned room temperature and / or pressure.

[0083]

[0084] The first aspect of this article is,

[0085] A method for recycling a waste secondary battery electrode material is provided, comprising: (1) a step of preparing a lithium restoration solution by mixing a lithium salt and a solvent; and (2) a step of restoring lithium by immersing an electrode from which lithium has been lost in the prepared lithium restoration solution, wherein the electrode from which lithium has been lost is immersed in the lithium restoration solution in a state in which a current collector and a positive electrode active material formed on the current collector are formed.

[0086]

[0087] Hereinafter, a method for recycling waste secondary battery electrode materials according to the first aspect of the present invention will be described in detail.

[0088]

[0089] In one embodiment of the present invention, electrons can be supplied from the current collector to the positive electrode active material by galvanic corrosion between the metals contained in the current collector and the positive electrode active material. Galvanic corrosion occurs when two different metals come into contact with each other in an electrolyte, and this causes a potential difference to occur, resulting in the flow of current between the metals. As a result, corrosion of a metal with high corrosion resistance (anode) is suppressed and corrosion of a metal with high activity (anode) is promoted.

[0090]

[0091] In one embodiment of the present invention, the current collector is a metal current collector, and the metal may be selected from the group consisting of copper (Cu), aluminum (Al), platinum (Pt), gold (Au), nickel (Ni), titanium (Ti), iron (Fe), molybdenum (Mo) and mixtures thereof, and preferably aluminum (Al) may be selected, and the shape of the metal current collector may be various shapes such as a film, a sheet, a foil, a net, a porous body, a non-woven fabric body, etc. FIG. 1 is a schematic diagram showing the process of supplementing lithium to a waste secondary battery electrode material depending on the presence or absence of an aluminum current collector when an aluminum current collector is used as a metal current collector. When an aluminum current collector is present, the amount of lithium restored increases by a galvanic couple, and the reaction formula is as follows. (1) The reaction is Br - This is the process in which lithium is inserted to balance the charge neutrality while transferring electrons to the positive electrode material during the process of oxidation and becoming Br2. (1) After the reaction, (2) the reaction progresses, corrosion occurs in the aluminum current collector, and Al 0 This Al 3+ It oxidizes and transfers electrons to the cathode material. At this time, since the reducing power of aluminum is high, sufficient lithium can be inserted into the cathode material.

[0092] (1) Li 0.76 Ni 0.6 Co 0.2 Mn 0.2O2+ 0.1Li + 0.1e - → Li 0.86 Ni 0.6 Co 0.2 Mn 0.2 O2

[0093] (2) Li 0.86 Ni 0.6 Co 0.2 Mn 0.2 O2+ 0.14Li + 0.14e - → Li1Ni 0.6 Co 0.2 Mn 0.2 O2

[0094] In the absence of an aluminum collector, reaction equation (3) is as follows.

[0095] (3) Li 0.76 Ni 0.6 Co 0.2 Mn 0.2 O2+ 0.1Li + 0.1e - → Li 0.86 Ni 0.6 Co 0.2 Mn 0.2 O2

[0096] In one embodiment of the present invention, the lithium salt of step (1) is not particularly limited, and any lithium salt that can be used in the relevant technical field may be used. For example, LiBr, LiI, LiCl, LiF, LiPF6, LiB 10 Cl 10 , LiBF4, LiBF6, LiSbF6, LiAsF6, LiSO3CF3, LiCF3SO3, LiC(SO2CF3)3, Li(CF3SO2)2N, LiN(C2F5SO2)2, LiClO4, LiAlO4, LiAlCl4, LiPF6, LiClO4, LiCF3SO3, LiC4F9SO3, LiAlO2, LiN(CxF 2x+1 SO2)(CyF 2y+1SO2)(x, y are 1 to 20), LiNO3, LiOAc, LiSCN, (CF3SO2)2Nli, CH3SO3Li, CF3SO3Li, lithium chloroborane, lithium tetraphenylborate or mixtures thereof can be used, and preferably, LiBr can be used as the lithium salt.

[0097]

[0098] In one embodiment of the present invention, the solvent of step (1) may be water, distilled water, acetonitrile, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethylmethyl carbonate (EMC) or methylethyl carbonate (MEC), methyl propionate (MP), fluoroethylene carbonate (FEC), fluorobenzene (FB), vinylene carbonate (VC), vinylethylene carbonate (VEC), phenylethylene carbonate (PhEC), propylmethyl carbonate (PMC), diethoxyethane (DEE), dimethoxyethane (DME), tetrahydrofuran (THF), γ-butyrolactone (GBL), γ-valerolactone (GVL), or a mixture thereof, and acetonitrile may be preferably used as the solvent.

[0099] In one embodiment of the present invention, the lithium restoration solution of step (1) may have a lithium salt concentration of 0.05 M to 0.5 M, preferably a lithium salt concentration of 0.1 M to 0.3 M, and more preferably a lithium salt concentration of 0.2 M.

[0100] In one embodiment of the present invention, the step (2) may be performed at a temperature of 10 to 80°C, preferably 15 to 45°C, and more preferably 15 to 35°C. If the temperature is below the above-mentioned range, it may become an excessively low-temperature process, and lithium restoration may not be achieved as much as necessary. If the temperature exceeds the above-mentioned range, it may be difficult to regard it as a process close to room temperature, and it may be inefficient from an energy perspective, and further, it may be difficult to regard it as environmentally friendly.

[0101] In one embodiment of the present invention, the step (2) may be performed at a pressure of 0.8 to 1.3 bar, and preferably at a pressure of 1.0 bar. In the conventional technology, the technology for replenishing lithium to a waste electrode material was performed at high temperature and high pressure, but according to one embodiment of the present invention, the technology may be different from the conventional technology in that the lithium is restored by immersing the electrode that has lost lithium in a lithium restoration solution at room temperature and pressure.

[0102] In one embodiment of the present invention, step (2) may be performed for 0.5 to 72 hours, preferably for 12 to 24 hours, and more preferably for 24 hours.

[0103] In one embodiment of the present invention, the electrodes from which lithium has been lost in step (2) may be a plurality of electrodes each having a different degree of lithium loss and different deterioration. Fig. 7 is a graph showing the relative contents of lithium in samples with different lithium distributions and the amount of lithium restored when restored. The relative contents of lithium in Sample 1 and Sample 2 were 50% and 75%, respectively, and after lithium was restored, the relative contents of lithium in restored Samples 1 and 2 were measured to be 95%, respectively. This means that even if the degrees of lithium loss are different in the plurality of electrodes from which lithium has been lost, lithium replenishment is similar to the initial state.

[0104] In one embodiment of the present invention, the method may further include a step of washing and drying the electrode restored by the step (2), preferably, the washing may be performed using dimethyl carbonate (DMC) or acetone, and the drying may be performed at a temperature of 15 to 45°C, preferably at a temperature of 15 to 25°C.

[0105] In one embodiment of the present invention, the positive electrode active material is LCO(LiCoO2), NCM(Li[Ni,Co,Mn]O2), NCA(Li[Ni,Co,Al]O2), LLNCMO(Li[Li,Ni,Co,Mn]O2), LMO(LiMn2O4), LTO(Li 14 Ti 15 O 12 ), LFP (LiFePO4), LMP (LiMnPO4) or LCP (LiCoPO4), and preferably, nickel, cobalt or manganese, and more preferably, NCM622 containing nickel, cobalt and manganese in a weight ratio of 6:2:2, respectively.

[0106]

[0107] According to an embodiment of the present invention, lithium can be supplemented to a waste secondary battery electrode material in a simple manner under room temperature and pressure conditions, thereby facilitating recycling of waste secondary battery electrode materials by collecting waste secondary battery electrode materials with various degrees of deterioration into a single distribution, and thus it can be considered to have industrial applicability.

Claims

1. (1) A step of preparing a lithium restoration solution by mixing a lithium salt and a solvent; and (2) a step of restoring lithium by immersing an electrode from which lithium has been lost in the manufactured lithium restoration solution; A method for recycling a waste secondary battery electrode material, characterized in that the electrode from which the lithium has been lost is immersed in the lithium restoration solution in a state in which a current collector and a cathode active material formed on the current collector are formed.

2. In paragraph 1, A method for recycling a waste secondary battery electrode material, characterized in that electrons are supplied from a current collector to a positive electrode active material by galvanic corrosion between metals contained in the current collector and the positive electrode active material.

3. In paragraph 1, The above collector is an aluminum collector, A method for recycling a waste secondary battery electrode material, characterized in that the electrode material is in the form of any one of a film, a sheet, a foil, a net, a porous body, a foam, and a non-woven fabric.

4. In paragraph 1, The lithium salt of step (1) above is LiBr, LiPF 6 , LiBF 4 , LiBF 6 , LiB 10 Cl 10 , LiSbF 6 , LiAsF 6 , LiSO 3 CF 3 , LiCF 3 SO 3 , LiC(SO 2 CF 3 ) 3 , LiN(CF 3 SO 2 ) 2 , LiN(C 2 F 5 SO 2 ) 2 , LiClO 4 , LiAlO 4 , LiNO 3 , LiOAc, LiF, LiCl, LiSCN, LiI, (CF 3 SO 2 ) 2 Nli, CH 3 SO 3 Li, CF 3 SO 3 Li, lithium chloroborane, lithium tetraphenylborate and LiAlCl 4 A method for recycling waste secondary battery electrode materials, characterized by having any one of the following properties.

5. In paragraph 1, The solvent of step (1) above is A method for recycling a waste secondary battery electrode material, characterized in that the solvent is any one of water, distilled water, acetonitrile, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethylmethyl carbonate (EMC) or methylethyl carbonate (MEC), methyl propionate (MP), fluoroethylene carbonate (FEC), fluorobenzene (FB), vinylene carbonate (VC), vinylethylene carbonate (VEC), phenylethylene carbonate (PhEC), propylmethyl carbonate (PMC), diethoxyethane (DEE), dimethoxyethane (DME), tetrahydrofuran (THF), γ-butyrolactone (GBL) and γ-valerolactone (GVL).

6. In paragraph 1, A method for recycling a waste secondary battery electrode material, characterized in that the lithium restoration solution of step (1) contains a lithium salt at a concentration of 0.05 M to 0.5 M.

7. In paragraph 1, A method for recycling a waste secondary battery electrode material, characterized in that the above step (2) is performed at a temperature of 15 to 80°C.

8. In paragraph 1, A method for recycling a waste secondary battery electrode material, characterized in that the step (2) above is performed at a pressure of 0.8 to 1.3 bar.

9. In paragraph 1, A method for recycling a waste secondary battery electrode material, characterized in that the above step (2) is performed for 0.5 to 72 hours.

10. In paragraph 1, A method for recycling a waste secondary battery electrode material, characterized in that the electrodes in which lithium has been lost in the above step (2) are a plurality of electrodes each independently having different degrees of lithium loss.

11. In paragraph 1, A method for recycling a waste secondary battery electrode material, characterized in that it further includes a step of washing and drying the electrode restored by the step (2) above.

12. In paragraph 11, A method for recycling waste secondary battery electrode materials, characterized in that the washing is performed using dimethyl carbonate (DMC) or acetone.

13. In paragraph 1, The above positive electrode active material is LCO (LiCoO 2 ), NCM(Li[Ni,Co,Mn]O 2 ), NCA(Li[Ni,Co,Al]O 2 ), LLNCMO(Li[Li,Ni,Co,Mn]O 2 ), LMO(LiMn 2 O 4 ), LTO(Li 14 Ti 15 O 12 ), LFP(LiFePO 4 ), LMP(LiMnPO 4 ) or LCP(LiCoPO 4 ) A method for recycling a waste secondary battery electrode material, characterized by including a.

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