Comprehensive recycling of Al foil and active materials from the spent lithium-ion battery

Abstract

Traditional methods of separating positive active materials and Al foil not only leads to the impurities entering the recovery process, but also consumes a lot of energy. Furthermore, lithium is usually recovered in the last step of traditional recovery process, which leads to a high loss rate. In this investigation, an electrolytic method is proposed to separate positive active materials from Al foil and the majority of lithium can be recovered preferentially. In this process, positive active materials are completely separated from Al foil, while the Al foil can be kept intact. Most of Li is dissolved into the solution except for Ni, Co, and Mn. The Cu impurity in active materials is firstly dissolved into solution and then deposited onto the cathode of electrolytic cell. Therefore, there are no impurities affecting the recovery of lithium by precipitation. LiNi0.6Co0.2Mn0.2O2 material with excellent electrochemical properties is resynthesized directly without removing impurities. The parameters such as supply voltage, inter-electrode distance, the concentration of Na2SO4 and the type of the electrode which affect the effect of electrolytic separation and lithium dissolution are investigated. At the same time, the separation mechanism between positive active material and Al foil is also explored.