Integrating trace Ti-doping and LiYO2-coating to stabilize Ni-rich cathodes for lithium-ion batteries

Abstract

Ni-rich layered cathodes have become the promising candidates for the next-generation high-energy Li-ion batteries due to their high energy density and competitive cost. However, they suffer from rapid capacity fading due to the structural and interfacial instability upon long-term operation. Herein, the Ti-doped and LiYO2-coated Ni-rich layered cathode has been synthesized via a facile one-step sintering strategy, which significantly restrains the interfacial parasitic side reactions and enhances the structural stability. Specifically, the trace Ti4+ doping greatly stabilizes the lattice oxygen and alleviates the Li/Ni disorder while the LiYO2 coating layer can prevent the erosion of the cathode by the electrolyte during cycles. As a result, the Ti-NCM83@LYO delivers a high specific capacity of 135 mAh g−1 even at 10C and there is almost no capacity loss at 1C for 100 cycles. This work provides a simple one-step dual-modification strategy to meet the commercial requirements of Ni-rich cathodes.