ANODE RECOVERY IN RECYCLED BATTERIES
DRIVE
December 9, 2021
A method for recycling anode materials from a comingled recycling stream derived from exhausted Li ion batteries includes receiving a precipitate quantity remaining from a cathode recycling stream. This precipitate is almost exclusively graphite used for the anode material in the recycled batteries. The precipitate results from an acid leach of charge material from the lithium battery recycling stream. A strong acid is added to the precipitate for removal of residual cathode and separator materials and the mixture heated. The strong acid removes residual aluminum oxide from the separator by transformation to aluminum sulfate. Washing the acid treated precipitate removes water soluble contaminants, such as the aluminum sulfate reacted from the aluminum oxide and sulfuric acid, to generate substantially pure graphite. Any residual material remaining from the cathode recycling phase is also removed.
Discussion in the ATmosphere