Abstract: The present disclosure provides a direct synthesis method for making a cathode active material by utilizing used cathode active material. This method utilizes a hydrothermal process comprising mixing a black mass or a processed black mass with an acid solution to generate a first solution, separating at least a portion of undissolved particles from the first solution, generating a second solution by mixing the first solution with a base solution under a hydrothermal condition to synthesize the cathode active material, and separating the cathode active material from the second solution.

Abstract: The present disclosure provides a method for making a coated single crystalline cathode active material. The continuous hydrothermal manufacturing process may include several steps: a) preheating a metal solution, a lithium solution, and a coating solution; b) generating a first mixture by mixing the metal solution and the lithium solution at below a critical point of the first mixture; c) generating a second mixture by mixing the first mixture and the coating solution above a critical point of the second mixture to synthesize the coated single crystalline cathode active material; and d) filtering out the coated single crystalline cathode active material.

Abstract: The present disclosure provides a method for making a coated single crystalline cathode active material. The continuous hydrothermal manufacturing process may include several steps: a) preheating a metal solution, a lithium solution, and a coating solution; b) generating a first mixture by mixing the metal solution and the lithium solution at below a critical point of the first mixture; c) generating a second mixture by mixing the first mixture and the coating solution above a critical point of the second mixture to synthesize the coated single crystalline cathode active material; and d) filtering out the coated single crystalline cathode active material.

Abstract: The present disclosure provides a method for making a coated single crystalline cathode active material. The continuous hydrothermal manufacturing process may include several steps: a) preheating a metal solution, a lithium solution, and a coating solution; b) generating a first mixture by mixing the metal solution and the lithium solution at below a critical point of the first mixture; c) generating a second mixture by mixing the first mixture and the coating solution above a critical point of the second mixture to synthesize the coated single crystalline cathode active material; and d) filtering out the coated single crystalline cathode active material.

Abstract: The present disclosure provides a cathode active material. The cathode active material includes a deagglomerated single crystalline particle including layered lithium nickel manganese oxide, a metal oxide coating in contact with the layered lithium nickel manganese oxide, and a carbon coating in contact with the metal oxide coating. The cathode active material includes a deagglomerated single crystalline particle including lithium iron manganese phosphate, a metal phosphate coating in contact with the lithium iron manganese phosphate, and a carbon coating in contact with the metal phosphate coating.