Recycling Spent LiCoO₂ for Improved 4.6 V Performance

High Resolution Image Download MS PowerPoint Slide Rapid replacement of “3C” (computer, communication, and consumer electronics) products and the limited calendar life of batteries lead to the increasing retirement of LiCoO 2 (LCO)-based lithium-ion batteries (LIBs), which makes recycling in high demand for a sustainable development. Herein, we propose a straightforward sintering process to rejuvenate the spent LCO to achieve a much-favored cycling stability at 4.6 V. The addition of Mg 3 (PO 4 ) 2 is critical for restoring the structure of spent LCO after heat treatment, enabling a synergistic effect of bulk Mg 2+ doping and surface Li 3 PO 4 decoration in the reconstructed LCO. This structural modification effectively suppresses harmful O3/H1–3 phase transitions and enhances Li + transport dynamics, thereby endowing the recycled LCO with extraordinary cycling stability and rate performance. In the 4.5 V LCO/graphite pouch cell, a capacity retention of 75% is achieved after 480 cycles. Our work provides an efficient route for recycling and reusing spent LCO cathode materials, showing promise for practical applications.