High-entropy doping for high-performance zero-cobalt high-nickel layered cathode materials

Abstract

Considering the high price and scarcity of cobalt resource, zero-cobalt, high-nickel layered cathode material (LNM) have been considered as the most promising material for next-generation high-energy-density lithium-ion batteries (LIBs). However, current LNM faces severe structural instability and poor electrochemical performance. Here, high-entropy doping strategy has been developed to prepare high-performance LNM by a typical co-precipitation method. Supported by transmission electron microscopy, In-situ X-ray diffraction and X-ray absorption near edge structure analysis, the material exhibits small crystal size variations and no changes of (Ni, Mn)-O and (Ni, Mn)-Ni coordination distances, resulting in greatly reduced irreversible phase transformation and cracks. Formation energy and diffusion energy barrier analysis indicates that the material has a fast lithium-ion diffusion kinetics. Benefiting from these advantages, it exhibits excellent rate and cycling performances. This study provides a feasible high-entropy doping strategy to effectively achieve stable material circulation under the high capacity and give more insights for developing new high-energy-density cathode materials