Enhancement on structural stability of Ni-rich cathode materials by in-situ fabricating dual-modified layer for lithium-ion batteries

摘要

Ni-rich cathodes have been considered as promising cathodes for Li-ion batteries (LIBs) because their high electrochemical capacities and low costs. However, fast capacity fading caused by interfacial instability and bulk structural degradation of Ni-rich cathodes during charge-discharge processes severely hinders their development and application. To address these challenges, we report a one-step dual-modification strategy to in-situ synthesize complex In2O3&LiInO2 co-coating layer on the surface of LiNi0.8Co0.1Mn0.1O2, which can cooperate collaboratively to stabilize layered structure and deplete lithium impurity. The dual-modified LiNi0.8Co0.1Mn0.1O2 materials not only show distinguished cycling stability at 1 C with a capacity retention of ca. 90%, but also exhibit a discharge capacity of 177.1 mAh g(-1) at a high rate of 5 C with a capacity retention of 86.4% after 300 cycles. Further studies confirm structural degradation and intergranular cracks at the particle level can be effectively mitigated by uniformly adherent bi-functional coating layer even after long-term cycling. The results shed light on the feasibility of dual-modified strategy for improving the performance of Ni-rich cathode materials, which can also be applied to other oxide cathode materials.