This invention discloses a method for preferentially extracting
lithium from spent
lithium batteries using
slurry electrolysis technology. The method includes: sequentially discharging and disassembling spent
lithium batteries to obtain positive
electrode sheets or a mixture of positive and negative
electrode sheets; calcining the positive
electrode sheets or the mixture of positive and negative electrode sheets, and sieving to obtain positive electrode
powder or a mixture of positive and negative electrode
powder; adding the positive electrode
powder or the mixture of positive and negative electrode powder to dilute
sulfuric acid and stirring to obtain a
slurry; transferring the
slurry to an
electrolytic cell, electrolyzing the slurry, and filtering to obtain a lithium-
ion-rich solution. This method, by adjusting the slurry of spent lithium batteries and adding a suitable
electric field, utilizes electrochemical oxidation and
electric field migration to promote the migration of lithium ions from the
crystal structure of the positive
electrode material into the solution, while simultaneously oxidizing and dissolving the
metallic lithium deposited on the negative
electrode material. This achieves selective lithium extraction under low-acid conditions, while preventing the leaching of other valuable elements besides lithium, thus achieving the goal of preferential lithium extraction.