Improving electrochemical properties and structural stability of lithium manganese silicates as cathode materials for lithium ion batteries via introducing lithium excess

• DOI: 10.1002/er.4932
• Publication Date: 2019-11-20T09:26:20Z
• Authors: Min Wang; Chuan Ding; Yingchun Miao; Tianyu Liu; Kang Hang; Jintao Zhang
• Keywords: Structural Stability

The serious capacity decay caused by structural amorphization is still a major issue for polyanion-type lithium manganese silicates (Li2MnSiO4) as cathode material ion batteries. In this work, new strategy alleviating the instability via introduction of excess into host crystal lattice provided. A comprehensive study demonstrates that required energy extraction/insertion ions was decreased result changed local environment cations in compound after occupancy lattice. Importantly, it found Li-rich samples deliver higher reversible and increased average potential than pristine sample, indicating improved density Li2 + 2xMn1 − xSiO4/C. Additionally, structure Li2.2 sample kept intact, while Li2.0 transformed to amorphous state at 200 mA h g−1 during initial charging process controlling charge cut-off potential. As expected, certain amount Li2MnSiO4 explored route achieving with more movable lithium, maintaining its stability cyclic stability.