Li 2 Cu 0.1 Ni 0.9 O 2 with Copper Substitution: A New Cathode Prelithiation Additive for Lithium-Ion Batteries

Li 2 NiO 2 cathode prelithiation additive has been successfully applied to compensate the initial capacity loss (ICL) in Li-ion batteries (LIBs) industry due to its facile feasibility. However, it suffers from inferior lithium compensation properties during the first cycle. Herein, we report a Cu-substituted Li 2 Cu 0.1 Ni 0.9 O 2 to address this issue. As a new cathode prelithiation additive, Li 2 Cu 0.1 Ni 0.9 O 2 reveals considerably promoted lithium compensation performances: an enhanced initial charge capacity of 465 mAh g –1 and a reversible discharge capacity of 139.6 mAh g –1 are obtained; Li 2 Cu 0.1 Ni 0.9 O 2 delivers an irreversible capacity of 325.4 mAh g –1, which can effectively offset the ICL. When applied in the cathode side of a graphite/NCM811 full-cell, an exceptional initial charge capacity (277.3 mAh g –1 ) and discharge capacity (186.5 mAh g –1 ) can be achieved. This work provides a new prospect for cathode prelithiation additives for next-generation LIBs.