Regeneration of Al-doped LiNi0.5Co0.2Mn0.3O2 cathode material by simulated hydrometallurgy leachate of spent lithium-ion batteries

Abstract

A uniform Al-doped LiNi0.5Co0.2Mn0.3O2 cathode material was prepared using a coprecipitation method to take advantage of the positive effect of Al on regenerated NCM (Ni, Co, Mn) cathode materials and ameliorate cumbersome and high-cost impurity removal processes during lithium-ion battery recycling. When the Al3+ content in the leachate was 1 at.% with respect to the total amount of transition metals (Ni, Co, and Mn), the produced Al-doped NCM cathode material increased concentrations of lattice oxygen and Ni2+. The initial specific capacity at 0.1C was 167.4 mA·h/g, with a capacity retention of 79.1% after 400 cycles at 1C. Further, this Al-doped sample showed improved rate performance and a smaller electrochemical impedance. These findings provide a reference for developing industrial processes to resynthesize cathode materials with improved electrochemical performance by incorporating Al3+ impurities produced during lithium-ion battery recycling.