Hybrid Surface Modification and Bulk Doping Enable Spent LiCoO2 Cathodes for High‐Voltage Operation

at 0.2 C with excellent capacity retention of 80.9% (0.5 C) after 200 cycles at a cut-off voltage of 4.6 V, along with 96.3% of capacity retention over 100 cycles at 4.5 V. These findings may afford meaningful construction for the upcycling of commercial S-LCO into next-generation upmarket cathode materials through the elaborate surface and bulk modification design.