Sustainable recycling of LiCoO2 cathode scrap on the basis of successive peroxymonosulfate activation and recovery of valuable metals

Abstract

Increasing demand and waste of lithium-ion batteries (LIBs) has adversely affected resources and the environment. Multistage utilization of spent LIBs is essential to their sustainable development. Here, we propose a simple recycling method of LiCoO2 cathode scrap, based on the first use of the cathode scrap as a catalyst to degrade organic pollutants via peroxymonosulfate activation, and subsequent recovery of valuable metals from the used catalyst. Compared with pristine LiCoO2, the LiCoO2 cathode scrap exhibits excellent catalytic performance due to the active sites generated, such as the vacancy generation and electronic structure modulation by the degradation of LiCoO2 during the continuous lithiation and delithiation processes. The removal efficiency of cathode scrap to the o-phenylphenol exceeds 98% within 60 min, and the degradation efficiency is still above 95% after the 10th use because its unique sandwich and porous structure ensure the stability and recyclability. After multiple catalytic reactions, due to the generation of crack, the separation of the sandwich structure, and further degradation of active materials, the leaching efficiency of transition metals from the cathode scrap in deep eutectic solvent is promoted. 86% of lithium and 95% of cobalt are leached from the used catalyst respectively. This study provides a promising strategy for the sustainable development of LIBs and promotes the utilization of spent LIBs in multiaspect.