Li2Cu0.1Ni0.9O2 with Copper Substitution: A New Cathode Prelithiation Additive for Lithium-Ion Batteries

Li2NiO2 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 Li2Cu0.1Ni0.9O2 to address this issue. As a new cathode prelithiation additive, Li2Cu0.1Ni0.9O2 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; Li2Cu0.1Ni0.9O2 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.

Automated summary

Li2NiO2 cathode prelithiation additive has been successfully used in Li-ion batteries industry to compensate the initial capacity loss (ICL), but the lithium compensation properties during the first cycle are inferior. In this study, a Cu-substituted Li2Cu0.1Ni0.9O2 is reported to address this issue. Li2Cu0.1Ni0.9O2 shows considerably improved lithium compensation performances, with enhanced initial charge capacity and reversible discharge capacity, effectively offsetting the ICL. When applied in a graphite/NCM811 full-cell, exceptional initial charge capacity and discharge capacity can be achieved. This work provides new possibilities for cathode prelithiation additives for next-generation LIBs.