锂离子电池高容量富锂锰基正极材料研究进展

Research progress on the Li-excess Mn-based cathode materials with high capacity for lithium-ion battery

富锂锰基正极材料因具有高的放电比容量,有望成为下一代400 W·h/kg动力电池最有前景的正极材料。本文简要介绍了本研究团队在富锂锰基正极材料方面的研究进展。通过团队多年研发,材料的首次不可逆容量、倍率性能、循环稳定性得到明显的改善,而且,电压衰减被有效的抑制。同时,研制出基于富锂锰基正极材料和纳米硅碳负极材料的新型24 A·h高容量锂离子电池,其质量能量密度达到374 W·h/kg,体积能量密度达到577 W·h/L。

It is a goal for all-electric vehicles that the requirement of the energy density for Li-ion batteries must be over 400 W·h/kg in demand. In this review, the recent progresses of Li-rich layered oxide cathode materials in our group are briefly introduced. After many years＇ research, their initial coulombic efficiency, the rate capability and cycling performance were improved significantly. Moreover, the voltage decay was suppressed effectively. Based on these processes we also manufactured a 24 A·h-class cell using a Li-rich layered cathode and a Nano Si/C anode. The cell is confirmed to have the mass energy density of 374 W·h/kg and the volumetric energy density of 577 W·h/L.