Method for recovering positive electrode active material precursor

Abstract

A method for recovering a cathode active material precursor according to an embodiment of the present invention includes the steps of preparing a cathode active material mixture containing a lithium composite oxide, separating lithium from the cathode active material mixture to form a preliminary transition metal precursor, treating the preliminary transition metal precursor with an acid to form a composite transition metal salt solution, and mixing an acidic extractant with the composite transition metal salt solution, followed by adding a basic compound to recover the composite transition metal precursor, thereby improving the extraction rate of the transition metal.

Description

[Technical field]

[0001] The present invention relates to a method for recovering a positive electrode active material precursor, and more particularly to a method for recovering a positive electrode active material precursor from a positive electrode active material mixture. [Background technology]

[0002] Secondary batteries are batteries that can be repeatedly charged and discharged, and have been widely applied to portable electronic communication devices such as camcorders, mobile phones, and notebook computers with the development of the information and communication and display industries. Examples of secondary batteries include lithium secondary batteries, nickel-cadmium batteries, nickel-hydrogen batteries, etc. Among them, lithium secondary batteries have been actively developed and applied because of their high operating voltage and high energy density per unit weight, as well as their advantages in terms of charging speed and weight reduction.

[0003] The lithium secondary battery may include an electrode assembly including a positive electrode, a negative electrode, and a separator, and an electrolyte impregnated in the electrode assembly. The lithium secondary battery may further include, for example, a pouch-shaped exterior material that contains the electrode assembly and the electrolyte.

[0004] The positive electrode active material of the lithium secondary battery may be a lithium composite oxide, which may further contain a transition metal such as nickel, cobalt, or manganese.

[0005] The lithium composite oxide as the positive electrode active material can be produced by reacting a lithium precursor with a nickel-cobalt-manganese (NCM) precursor containing nickel, cobalt and manganese.

[0006] The use of the high-cost valuable metals in the positive electrode active material accounts for more than 20% of the manufacturing cost. In addition, in recent years, as interest in environmental protection has increased, research into methods for recycling positive electrode active materials has been progressing. In order to recycle the positive electrode active material, it is necessary to regenerate the lithium precursor from the waste positive electrode with high efficiency and high purity.

[0007] For example, Korean Patent Publication No. 2015-0002963 discloses a method for recovering lithium using a wet method. However, since cobalt, nickel, etc. are extracted and lithium is recovered from the remaining waste liquid by wet extraction, the recovery rate may be excessively low and a large amount of impurities may be generated from the waste liquid. Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a method for recovering a positive electrode active material precursor from a positive electrode active material mixture with high purity, high yield and high efficiency. [Means for solving the problem]

[0009] A method for recovering a cathode active material precursor according to an exemplary embodiment of the present invention includes the steps of preparing a cathode active material mixture including a lithium composite oxide, separating lithium from the cathode active material mixture to form a preliminary transition metal precursor, treating the preliminary transition metal precursor with an acid to form a composite transition metal salt solution, and mixing the composite transition metal salt solution with an acidic extractant, and then adding a basic compound to recover the composite transition metal precursor.

[0010] In some embodiments, forming the pre-transition metal precursor can include reducing the cathode active material mixture with hydrogen to form a pre-precursor mixture, and washing the pre-precursor mixture with water to separate lithium.

[0011] In some embodiments, the step of forming the composite transition metal salt solution may involve treating the preliminary transition metal precursor with an acid so that the composite transition metal salt solution has a pH of 0.1 to 2.0.

[0012] In some embodiments, forming the composite transition metal salt solution can include acid treating the pre-transition metal precursor with sulfuric acid.

[0013] In some embodiments, the complex transition metal salt solution can include a sulfate salt of a transition metal complex including at least two or more transition metals selected from the group consisting of nickel, cobalt, and manganese.

[0014] In some embodiments, the acidic extractant may include at least one selected from the group consisting of phosphoric acid-based extractants, phosphate-based extractants, and phosphine oxide-based extractants.

[0015] In some embodiments, the acidic extractant can further comprise a diluent.

[0016] In some embodiments, the diluent may include at least one selected from the group consisting of kerosene, hexane, benzene, and toluene.

[0017] In some embodiments, the step of recovering the complex transition metal precursor may include mixing the complex transition metal salt solution with the acidic extractant such that an organic phase / aqueous phase ratio is 2-10.

[0018] In some embodiments, the step of recovering the complex transition metal precursor may include adding a basic compound to the mixture of the complex transition metal salt solution and the acidic extractant so that the equilibrium pH is 3.5 to 6.

[0019] In some embodiments, the basic compound may include at least one selected from the group consisting of lithium hydroxide, sodium hydroxide, and potassium hydroxide. Effect of the Invention

[0020] According to an exemplary embodiment of the present invention, after the preliminary transition metal precursor from which the lithium precursor has been separated from the positive electrode active material mixture is subjected to an acid treatment, a high purity transition metal precursor can be obtained in high yield and high efficiency using an acidic extractant and a basic compound.

[0021] Since the lithium precursor is first separated from the positive electrode active material mixture and then the transition metal precursor is recovered, the transition metal precursor can be extracted at a high equilibrium pH, thereby improving the recovery rate of the transition metal (e.g., nickel).

[0022] In addition, by extracting transition metals collectively in the form of a composite transition metal precursor rather than extracting them individually, the extraction process can be simplified, thereby improving the extraction efficiency. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] In an exemplary embodiment of the present invention, the lithium precursor is first separated from the positive electrode active material mixture, and then the transition metal precursor is recovered using an acidic extractant and a basic compound, so that the positive electrode active material precursor can be recovered with high yield and high efficiency.

[0024] As used herein, the term "precursor" is used to refer collectively to a compound containing a specific metal to provide the specific metal contained in the electrode active material.

[0025] In the method for recovering a positive electrode active material precursor according to some embodiments, a positive electrode active material mixture including a lithium composite oxide can be prepared.

[0026] According to an exemplary embodiment, the positive electrode active material mixture may be obtained from a used lithium secondary battery. The used lithium secondary battery may include a lithium secondary battery that is substantially unable to be reused (charged or discharged), for example, a lithium secondary battery whose life span has been exhausted and whose charge / discharge efficiency has been significantly reduced, or a lithium secondary battery that has been destroyed by impact or chemical reaction.

[0027] The waste lithium secondary battery may include, for example, an electrode assembly including a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode. For example, the positive electrode and the negative electrode may include a positive electrode active material layer and a negative electrode active material layer coated on a positive electrode current collector and a negative electrode current collector, respectively.

[0028] For example, the positive electrode active material contained in the positive electrode active material layer can include an oxide containing lithium and a transition metal.

[0029] In some embodiments, the active cathode material may be an NCM-based lithium oxide containing nickel, cobalt, and manganese, but embodiments of the present invention are applicable to lithium-containing cathode materials as well as cathode materials containing the NCM-based lithium oxide.

[0030] For example, the positive electrode can be separated from the used lithium secondary battery to recover the used positive electrode. The positive electrode includes a positive electrode current collector (e.g., aluminum (Al)) and a positive electrode active material layer as described above, and the positive electrode active material layer may include a conductive material and a binder in addition to the positive electrode active material described above.

[0031] The conductive material may include, for example, a carbon-based material such as graphite, carbon black, graphene, carbon nanotubes, etc. The binder may include, for example, a resin material such as vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidene fluoride (PVDF), polyacrylonitrile, polymethylmethacrylate, etc.

[0032] For example, the positive electrode active material mixture may be prepared from the recovered positive electrode. As used herein, the term "positive electrode active material mixture" refers to a positive electrode active material mixture in which positive electrode current collector components such as aluminum have been substantially completely separated and removed from the recovered positive electrode, and in which the content of carbonaceous components derived from the conductive material and binder has been removed or reduced.

[0033] In some embodiments, the positive electrode active material mixture can be obtained in powder form by processing the recovered positive electrode by a physical method such as a grinding process. The positive electrode active material mixture can include a lithium-transition metal oxide powder as described above, for example, an NCM-based lithium oxide powder (e.g., Li(NCM)O2).

[0034] In some embodiments, the recovered positive electrode may be heat-treated before the pulverization treatment. This can promote detachment of the positive electrode current collector during the pulverization treatment, and can at least partially remove the binder and conductive material. The temperature of the heat treatment may be, for example, about 100 to 500°C, preferably about 350 to 450°C.

[0035] In some embodiments, the positive electrode active material mixture can be obtained after immersing the recovered positive electrode in an organic solvent. For example, the recovered positive electrode can be immersed in an organic solvent to separate and remove the positive electrode current collector, and the positive electrode active material mixture can be selectively extracted by centrifugation.

[0036] By the above-mentioned steps, it is possible to obtain a positive electrode active material mixture in which the content of the positive electrode current collector components and the carbonaceous components derived from the conductive material and / or binder is substantially removed or reduced.

[0037] The positive electrode active material mixture may include, for example, a lithium-containing compound used as a positive electrode active material in an electrochemical device. For example, a lithium composite oxide may be used as the positive electrode active material mixture.

[0038] For example, the lithium composite oxide may include lithium and a transition metal, such as nickel, cobalt, or manganese.

[0039] In some embodiments, the lithium composite oxide can be represented by Formula 1 below.

[0040] [ka]

[0041] In Chemical Formula 1, M is selected from the group consisting of Mn, Na, Mg, Ca, Ti, V, Cr, Cu, Zn, Ge, Sr, Ag, Ba, Zr, Nb, Mo, Al, Ga, and B; <x≦1.1、2≦y≦2.02、0.5≦a≦1、0≦b≦0.5であってもよい。

[0042] According to the exemplary embodiment, a lithium composite oxide having a Ni content of 0.5 molar ratio or more can be effectively converted into a lithium composite oxide.

[0043] The positive electrode active material mixture can further include various lithium-containing compounds such as, by way of non-limiting example, lithium oxide, lithium carbonate, lithium hydroxide, and the like.

[0044] In some embodiments, lithium can be separated from a prepared cathode active material mixture to form a preliminary transition metal precursor, for example, lithium can be separated from the cathode active material mixture in the form of lithium oxide or lithium hydroxide.

[0045] In an exemplary embodiment, forming the pre-transition metal precursor may include reducing the cathode active material mixture to form a pre-precursor mixture, and washing the pre-precursor mixture with water to separate the lithium.

[0046] For example, the preliminary positive active material mixture may be reduced with hydrogen to form a preliminary precursor mixture, and then the preliminary precursor mixture may be washed with water to separate a lithium precursor containing lithium hydroxide.

[0047] In some embodiments, the hydrogen reduction treatment can be performed using a fluidized bed reactor. For example, the positive electrode active material mixture can be placed in the fluidized bed reactor, and hydrogen gas can be injected from a lower portion of the fluidized bed reactor.

[0048] The hydrogen gas may form a cyclone at the bottom of the fluidized bed reactor, and the positive active material mixture may come into contact with the hydrogen to produce the pre-precursor mixture.

[0049] In some embodiments, a carrier gas may be mixed and injected into the lower portion of the fluidized bed reactor together with the hydrogen gas, thereby facilitating the formation of a reaction layer of the pre-precursor mixture in the fluidized bed reactor by promoting gas-solid mixing in the fluidized bed to promote the reaction.

[0050] The carrier gas can include, for example, an inert gas such as nitrogen (N2), argon (Ar), or the like.

[0051] The preliminary precursor mixture may include, for example, a hydrogen reduction product of the lithium-transition metal oxide included in the positive electrode active material mixture. When an NCM-based lithium oxide is used as the lithium-transition metal oxide, the preliminary precursor mixture may include a preliminary lithium precursor and a preliminary transition metal precursor.

[0052] The reserve lithium precursor may include lithium hydroxide, lithium oxide and / or lithium carbonate.

[0053] The transition metal component of the preliminary transition metal precursor may be derived from the lithium composite oxide in the recovered positive electrode. For example, the transition metal component may be separated in a reaction in which the lithium composite oxide is converted to lithium oxide to form the preliminary transition metal precursor. The preliminary transition metal precursor may include, for example, Ni, Co, NiO, CoO, MnO, etc.

[0054] The hydrogen reduction reaction can be carried out at about 400 to 700°C, preferably about 450 to 550°C.

[0055] The water washing process can convert the preliminary lithium precursor into a lithium precursor that is substantially composed of lithium hydroxide. For example, lithium oxide and lithium carbonate mixed in the preliminary lithium precursor can be converted into lithium hydroxide by reacting with water, or can be removed by washing with water. This can produce a high-purity lithium precursor that is converted into the desired lithium hydroxide form.

[0056] The reserve lithium precursor may react with water to dissolve and produce a substantially aqueous lithium hydroxide solution.

[0057] The pre-transition metal precursor contained in the pre-precursor mixture can be precipitated by the water washing process without dissolving or reacting in water, and thus the pre-transition metal precursor can be separated by a filtration process to obtain a lithium precursor containing high-purity lithium hydroxide.

[0058] In some embodiments, the water washing process can be performed under conditions where carbon dioxide (CO2) is excluded. For example, the water washing process can be performed in a CO2-free atmosphere (e.g., an air atmosphere from which CO2 has been removed), thereby preventing regeneration of lithium carbonate.

[0059] In one embodiment, the water provided during the water rinsing process can be purged with a CO2-depleted gas (eg, nitrogen purging) to provide a CO2-free atmosphere.

[0060] In some embodiments, the pre-transition metal precursor can be treated with an acid to form a complex transition metal salt solution, for example, a complex transition metal salt solution formed by reacting the pre-transition metal precursor with an acid, which can include a complex transition metal sulfate solution when sulfuric acid is used.

[0061] For example, the complex transition metal salt solution may contain nickel, cobalt or manganese. For example, the complex transition metal salt solution may refer to a solution of an acid salt of two or more transition metal complexes selected from the group consisting of nickel, cobalt and manganese.

[0062] In an exemplary embodiment, the preliminary transition metal precursor is placed in a sulfuric acid solution at a temperature of about 50 to 90° C., and the acid treatment can be carried out for about 60 to 500 minutes. For example, the average pH of the composite transition metal salt solution formed by the acid treatment may be about 0.1 to 2.0. When the temperature, time and pH ranges are satisfied, the acid salt solution of the transition metal complex can be more easily formed. In addition, the extraction efficiency of the transition metal can be improved.

[0063] For example, the solid-liquid ratio of the acid used in the acid treatment of the preliminary transition metal precursor may be about 140 g / L or less, more preferably, the solid-liquid ratio may be about 90 g / L to 130 g / L.

[0064] For example, the concentration of the acid used in the acid treatment of the preliminary transition metal precursor may be about 1.8 M or more. More preferably, the concentration of the acid may be about 1.8 M to 10 M.

[0065] When the solid-liquid ratio and the acid concentration are within the above ranges, a composite transition metal salt solution can be formed without adding an oxidation-reduction agent, and a high-purity transition metal composite can be recovered with high efficiency.

[0066] In some embodiments, the complex transition metal salt solution can be mixed with an acidic extractant, followed by the addition of a basic compound to recover the complex transition metal precursor.

[0067] In some exemplary embodiments, the acidic extractant may include at least one selected from the group consisting of phosphoric acid-based extractants, phosphate-based extractants, and phosphine oxide-based extractants.

[0068] For example, the acidic extractant may include at least one selected from the group consisting of di-2-ethylhexyl phosphoric acid, bis(2,4,4-trimethylpentyl)phosphinic acid, bis(2,4,4-trimethylpentyl)dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester, tributyl phosphate, and trioctyl phosphine oxide. More preferably, the acidic extractant may include di-2-ethylhexyl phosphoric acid. For example, the acidic extractant can improve the rate at which a transition metal is extracted from a composite transition metal salt solution (eg, the transition metal extraction rate).

[0069] In some exemplary embodiments, the acidic extractant may further include a diluent. For example, the diluent may be an organic solvent. For example, the organic solvent may include at least one selected from the group consisting of kerosene, hexane, benzene, and toluene. More preferably, the organic solvent may include kerosene.

[0070] In some exemplary embodiments, the composite transition metal salt solution and the acidic extractant can be mixed so that the ratio of the organic phase to the aqueous phase (organic phase / aqueous phase ratio) is 2 to 10. More preferably, the organic phase / aqueous phase ratio can be mixed so that the organic phase / aqueous phase ratio is 3 to 7. For example, within the range of the organic phase / aqueous phase ratio, the ratio of the organic phase and the aqueous phase is appropriate, and the separation efficiency of the composite transition metal precursor extracted per unit time can be further improved.

[0071] In some exemplary embodiments, a basic compound may be added to the mixture of the composite transition metal salt solution and the acidic extractant so that the equilibrium pH of the mixture is about 3.5 to 6. For example, the composite transition metal salt solution can extract transition metals in a relatively high pH range because lithium has already been separated once and the lithium content has been reduced. This can improve the extraction rate of transition metals, particularly nickel and cobalt.

[0072] For example, if the equilibrium pH of the mixture of the composite transition metal salt solution and the acidic extractant is below the aforementioned equilibrium pH range, the extraction rate of the transition metal may decrease.

[0073] For example, if the equilibrium pH of the mixture of the composite transition metal salt solution and the acidic extractant exceeds the above-mentioned equilibrium pH range, side reactions such as metal precipitation may occur. In addition, as the average pH of the composite transition metal salt solution increases, the metal loading in the organic phase increases, and the density and viscosity of the solution may increase. Therefore, the high density and high viscosity of the solution may reduce the fluidity of the organic phase, and the efficiency of phase separation with the aqueous phase may decrease.

[0074] In some exemplary embodiments, the basic compound may include at least one selected from the group consisting of lithium hydroxide, sodium hydroxide, and potassium hydroxide.

[0075] For example, the percentage concentration of the basic compound may be about 10-60%. When the percentage concentration of the basic compound is within the above range, the equilibrium pH of the mixture of the composite transition metal salt solution and the acidic extractant can be smoothly adjusted.

[0076] In an exemplary embodiment, a cathode active material precursor can be provided, and the cathode active material precursor can be subjected to appropriate processing to obtain a transition metal hydroxide, which can be used to manufacture an cathode active material.

[0077] In the following, preferred examples are presented to aid in understanding the present invention, but these examples are merely illustrative of the present invention and do not limit the scope of the appended claims. It is clear to those skilled in the art that various changes and modifications can be made to these examples within the scope of the scope and technical ideas of the present invention, and it is natural that these changes and modifications fall within the scope of the appended claims.

[0078] Example 1 1 kg of the positive electrode material recovered from waste lithium secondary batteries was heat-treated at 450°C, cut into small units, and pulverized by milling. The pulverized positive electrode material was sieved through a sieve with a mesh size of 80 μm to remove the positive electrode current collector component (Al) and carbon-based impurities, and a positive electrode active material mixture was obtained.

[0079] 10 g of the positive electrode active material mixture was charged into a column-type hydrogen reduction reactor, and 20% hydrogen gas was injected and reacted at 450° C. for 2 hours to obtain a preliminary precursor mixture.

[0080] The pre-precursor mixture was reacted with 100 ml of nitrogen-purged water, filtered through filter paper, and centrifuged to obtain a lithium-containing supernatant and a pre-precursor-containing precipitate.

[0081] After removing the lithium-containing supernatant, the preliminary transition metal precursor-containing precipitate was dried. 130 g of the dried precipitate was added to 1 L of 2 mol / L sulfuric acid to form a composite transition metal salt solution. The pH of the composite transition metal salt solution formed was 0.11.

[0082] An acidic extractant containing 1 mol / L di-2-ethylhexyl phosphoric acid and kerosene was added to the composite transition metal salt solution to form a mixture of the composite transition metal salt solution and the acidic extractant. The organic phase / aqueous phase ratio of the mixture was 6. Then, 50% sodium hydroxide was added to the mixture to adjust the equilibrium pH of the mixture to 4.74, thereby extracting the composite transition metal precursor.

[0083] Examples 2 to 8 The composite transition metal precursor was extracted in the same manner as in Example 1, except that the equilibrium pH and organic phase / aqueous phase ratio of the mixture of the composite transition metal salt solution and the acidic extractant were adjusted as shown in Table 1 below.

[0084] Comparative Example 1 1 kg of the positive electrode material recovered from waste lithium secondary batteries was heat-treated at 450°C, cut into small units, and pulverized by milling. The pulverized positive electrode material was sieved through a sieve with a mesh size of 80 μm to remove the positive electrode current collector component (Al) and carbon-based impurities, and a positive electrode active material mixture was obtained.

[0085] 200 g of the positive electrode active material mixture was added to 1 L of 3 mol / L sulfuric acid, and 35% H2O2 was added as a reducing agent in an amount of 10 vol% based on the amount of sulfuric acid added to form a composite transition metal salt solution, the pH of which was 0.48.

[0086] An acidic extractant containing 1 mol / L di-2-ethylhexyl phosphoric acid and kerosene was added to the composite transition metal salt solution to form a mixture of the composite transition metal salt solution and the acidic extractant. The organic phase / aqueous phase ratio of the mixture was 6. Then, 50% sodium hydroxide was added to the mixture to adjust the equilibrium pH of the mixture to 4.7, thereby extracting the composite transition metal precursor.

[0087] Comparative Examples 2 to 4 A composite transition metal precursor was extracted in the same manner as in Comparative Example 1, except that the equilibrium pH and organic phase / aqueous phase ratio of the mixture of the composite transition metal salt solution and the acidic extractant were adjusted as shown in Table 1 below.

[0088] [Table 1]

[0089] Experimental Example: Calculation of Metal Extraction Rate The weight percentages of the transition metals present in the aqueous phase before and after extraction were compared to calculate the extraction rate. The weight percentages of the transition metals present in the aqueous phase before and after extraction and the extraction rates calculated based thereon are shown in Table 2 below.

[0090] [Table 2]

[0091] As shown in Table 2 above, increasing the organic / aqueous phase ratio increased the extraction rate of metals due to the greater number of sites from which metals present in the organic phase can be extracted.

[0092] Referring to Example 5, when the average pH of the mixture of the composite transition metal salt solution and the acidic extractant exceeded 6.0, the amount of metal extracted increased, and the viscosity and density of the extractant increased, making it difficult to separate from the aqueous phase.

[0093] Referring to Table 2, when the organic phase / aqueous phase ratio of the composite transition metal salt solution, the acidic extractant and the basic compound was in the range of 2-10, and the equilibrium pH was in the range of 3.5-6, the extraction rate of the transition metal was improved.

Claims

1. Providing a positive electrode active material mixture including a lithium composite oxide; separating lithium from the cathode active material mixture to form a preliminary transition metal precursor; treating the pre-transition metal precursor with an acid to form a composite transition metal salt solution; and mixing an acidic extractant with the composite transition metal salt solution so that the organic phase / aqueous phase ratio is 6 to 10, and then adding a basic compound so that the equilibrium pH is 3.5 to 6.1, thereby recovering the transition metal precursor.

2. 2. The method for recovering a positive electrode active material precursor according to claim 1, wherein the step of forming the preliminary transition metal precursor comprises the steps of: reducing the positive electrode active material mixture with hydrogen to form a preliminary precursor mixture; and washing the preliminary precursor mixture with water to separate lithium.

3. 2. The method for recovering a positive electrode active material precursor according to claim 1, wherein the step of forming the composite transition metal salt solution comprises treating the preliminary transition metal precursor with an acid so that the composite transition metal salt solution has a pH of 0.1 to 2.

0.

4. The method for recovering a positive electrode active material precursor according to claim 1 , wherein the step of forming the composite transition metal salt solution comprises acid-treating the preliminary transition metal precursor with sulfuric acid.

5. 5. The method for recovering a positive electrode active material precursor according to claim 4, wherein the composite transition metal salt solution contains a sulfate of a transition metal complex containing at least two or more transition metals selected from the group consisting of nickel, cobalt, and manganese.

6. 2. The method for recovering a positive electrode active material precursor according to claim 1, wherein the acidic extractant includes at least one selected from the group consisting of a phosphoric acid-based extractant, a phosphate-based extractant, and a phosphine oxide-based extractant.

7. The method for recovering a positive electrode active material precursor according to claim 1 , wherein the acidic extractant further contains a diluent.

8. 8. The method of claim 7, wherein the diluent comprises at least one selected from the group consisting of kerosene, hexane, benzene, and toluene.

9. 2. The method for recovering a positive electrode active material precursor according to claim 1, wherein the step of recovering the transition metal precursor comprises adding a basic compound to the mixture of the composite transition metal salt solution and the acidic extractant so that the equilibrium pH is 3.5 to 6.

10. The method for recovering a positive electrode active material precursor according to claim 9 , wherein the basic compound includes at least one selected from the group consisting of lithium hydroxide, sodium hydroxide, and potassium hydroxide.

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