Short-term and High-performance Recycling of Cathode Material from Spent Lithium Ion Batteries

Abstract

In the industrial practice of spent lithium-ion battery recycling, mechanical separation, pyrometallurgy and chemical dissolution technologies are often used to achieve the separation and recovery of cathode materials, but there are problems such as low material dissociation rate, low recovery rate, high energy consumption, serious lithium loss, and impurity ion embedding. In this paper, supercritical CO₂ fluid was used to strengthen the separation of the cathode active material from the aluminum foil in the spent lithium-ion battery to achieve direct and efficient recovery of the active substance. The analysis of charge and discharge, AC impedance and differential capacitance curves show that the electrode of supercritical recovered material has higher ion diffusion coefficient and better redox reversibility, so it has higher charge and discharge capacity and better cycle stability than the traditional high-temperature calcined recovered material.