Abstract:

Spinel LiNi_0.5Mn_1.5O₄ cathode material has attracted much attention due to its high theoretical specific capacity,high theoretical specific energy,high working voltage,abundant resources and low price.However,its poor cycling performance and rate performance are caused by the decomposition of electrolyte and interface side reaction under high pressure,which restricts its popularization and application.Combined with the research reports in recent years,the structure and the mecha-nism of the intercalation,surface/interface chemistry,and modification methods of LiNi_0.5Mn_1.5O₄ cathode material are introdu-ced.The surface properties of LiNi_0.5Mn_1.5O₄,the interfacial reaction mechanism between different components and its influence on the electrochemical performance of cathode material are emphatically introduced.It proposes that the crystal plane orienta-tion,particle morphology,surface element distribution,coating and ion doping are effective ways to improve the electrochemi-cal performance of LiNi_0.5Mn_1.5O₄ material.At the same time,the development of suitable high-voltage electrolyte by solvent substitution,film-forming additives addition,changing the type and concentration of lithium salt is also an important method to improve the performance of LiNi_0.5Mn_1.5O₄ battery.Finally,the surface modification of LiNi_0.5Mn_1.5O₄ cathode material and the construction of electrolyte interface are summarized and prospected,which aims to provide reference for the related research on improving the performance of the material.

Key words: LiNi_0.5Mn_1.5O₄, interfacial chemistry, electrolyte decomposition, modification of cathode materials