高镍三元材料的高压稳定性研究进展

Research progress on high pressure stability of high nickel ternary materials

高镍三元材料LiNixMnyCo_(1-x-y)O_(2)(NCM)具有可逆容量大、工作电压高等优点,已成为锂离子电池的理想正极材料。然而,为满足远程电动汽车的需求,动力电池能量密度需达到400 Wh/kg,这是现有NCM材料无法实现的。提高截止电压是获得更高比容量的有效手段,有望满足能量密度需求。但是高截止电压会导致电化学性能的快速衰减。为了更好地提高高镍材料在高压下的稳定性,本文简述了高镍材料在高压下的性能衰减机理,重点总结了现有各种改性策略的研究进展,以及对NCM材料电化学性能的作用机理,展望其未来发展趋势和应用前景。

High-nickel terpolymer LiNixMnyCo_(1-x-y)O_(2)(NCM)has the advantages of large reversible capacity and high operating voltage,and has become an ideal cathode material for lithium-ion batteries.However,to meet the needs of long-range electric vehicles,the power battery energy density needs to reach 400 Wh/kg,which is not possible with existing NCM materials.Increasing cut-off voltage is an effective means to obtain higher specific capacity,which is expected to meet the energy density requirements.However,high cut-off voltage can lead to rapid attenuation of electrochemical performance.In order to better improve the stability of high nickel materials under high pressure,this paper briefly describes the performance attenuation mechanism of high nickel materials under high pressure,focuses on the current research progress of various modification strategies and the mechanism of action on the electrochemical properties of NCM materials,and looks forward to its future development trend and application prospect.