Directly-regenerated LiCoO2 with a superb cycling stability at 4.6 V

The exponential growth of "3C" (computer, communication, and consumer electronics) market generates an ever-increasing demand on recycling materials from the end-of-life LiCoO2 (LCO) batteries with ecological and efficient methods. Herein, we present a direct and scalable approach to recycle the degraded LCO by healing and stabilizing their damaged structure via solid reactions. The as-proposed approach constructs a protective layer onto the regenerated LCO particles to suppress the O3 to H1-3 phase transition at 4.55 V. Benefiting from the unique design, superb electrochemical performance was achieved for the regenerated LCO, exhibiting a high specific capacity retention of 85.9% after 100 cycles with a charging cut-off voltage of 4.6 V and a superb rate capability, which are even superior to those of the pristine commercial LCO. In addition, compared with the LCO production with raw chemicals, the as-proposed healing-stabilizing strategy reduces the total energy consump-tion by 68.5%, bringing noteworthy economic and environmental benefits. This work provides not only new understandings to stabilize LCO at high voltage, but also a practical solution to the closed-loop development of LCO batteries.