Method of making a cathode active material

1 . A method of making a cathode active material, the method comprising:

contacting a mixed metal composition with water to form a first solution, the mixed metal composition comprising

nickel, cobalt, manganese, aluminum, or a combination thereof; and

greater than 0 to 2 weight percent, based on the total weight of the mixed metal composition, of a compound comprising Cu, Fe, Mg, Na, Ca, Zn, F, Si, Li, or a combination thereof;

adding a salt of nickel, cobalt, manganese, aluminum, or a combination thereof to the first solution to provide a second solution;

combining the second solution and a basic solution to form a precipitate,

wherein the second solution comprises a stoichiometrically-adjusted mixed metal composition, and the stoichiometrically-adjusted mixed metal composition comprises 10 to 95 weight percent of the mixed metal composition, based on a total weight of the stoichiometrically-adjusted mixed metal composition;

adding a lithium compound to the precipitate to form a mixture; and

heat-treating the mixture to form the cathode active material.

2 . The method of claim 1 , wherein the mixed metal composition is obtained by a method comprising

contacting electrode particles comprising

nickel, cobalt, manganese, aluminum, or a combination thereof; and

greater than 0 to 2 weight percent, based on the total weight of the mixed metal composition, of a compound comprising Cu, Fe, Mg, Na, Ca, Zn, F, Si, Li, or a combination thereof;

with a leaching solution;

precipitating the mixed metal composition from the leaching solution; and

isolating the mixed metal composition from the leaching solution.

3 . The method of claim 1 , wherein the mixed metal composition comprises a mixed metal sulfate, a mixed metal nitrate, a mixed metal carbonate, a mixed metal halide, a mixed metal hydroxide, a mixed metal oxalate, or a combination thereof.

4 . The method of claim 1 , wherein mixed metal composition comprises:

nickel and cobalt, and

greater than 0 to 2 weight percent, based on the total weight of the mixed metal composition, of Cu, Fe, Mg, F, or a combination thereof.

5 . The method of claim 1 , wherein the mixed metal composition further comprises lithium 50 to 300 ppm Cu, 50 to 200 ppm of Al, 5 to 100 ppm of Fe, or 5 to 100 ppm of F, each based on the total weight of the mixed metal composition.

6 . The method of claim 1 , wherein at least a portion of the mixed metal composition is obtained from a recycled feedstock.

7 . The method of claim 1 , wherein the first solution has a pH of less than 7, or wherein the second solution has a pH of less than 7.

8 . The method of claim 1 , wherein the salt of nickel, cobalt, manganese, aluminum, or a combination thereof is a sulfate or a hydroxide thereof.

9 . The method of claim 1 , wherein the mixed metal composition comprises nickel, cobalt, and manganese, and the method comprises adding a salt of nickel, cobalt, and manganese to the first solution in an amount effective to provide a molar ratio of Ni:Co:Mn of greater than 0 to 1:greater than 0 to 1:greater than 0 to 1.

10 . The method of claim 1 , wherein the basic solution is combined with the second solution in an amount effective to provide a pH of greater than or equal to 10.

11 . The method of claim 1 , wherein the precipitate comprises Ni(OH) 2 , Co(OH) 2 , and Mn(OH) 2 .

12 . The method of claim 1 , wherein the precipitate comprises 5 to 100 ppm Li, based on the total weight of the precipitate.

13 . The method of claim 1 , wherein the lithium compound comprises lithium hydroxide, lithium carbonate, lithium oxide, lithium oxalate, or a combination thereof.

14 . The method of claim 1 , wherein the cathode active material comprises Ni, Co, Mn, Al, or combination thereof in an amount corresponding to Formula 1:

Li x MO 2 ,

wherein M is Ni, Co, Mn, Al, or a combination thereof and 0≤x≤1.4.

15 . The method of claim 1 , wherein the cathode active material comprises Ni, Co, Mn, Al, or combination thereof in an amount corresponding to Formula 2:

Li x Ni y Co z Mn v O 2 ,

wherein 0≤x≤1.4 and 0≤(y+z+v)≤1.1.

16 . The method of claim 1 , wherein the cathode active material comprises Ni, Co, Mn, Al, or combination thereof in an amount corresponding to Formula 3:

m Li 2 MnO 3 ·(1 −m )LiMO 2

wherein

M is Ni, Co, Mn, Al, or a combination thereof; and

0<m<1.

17 . The method of claim 1 , wherein the cathode active material comprises 0.33Li 2 MnO 3 ·0.66LiNi 0.6 Co 0.2 Mn 0.2 O 2 .

18 . The method of claim 1 , further comprising combining the cathode active material with a virgin cathode active material.