Enhancement on structural stability of Ni-rich cathode materials by in-situ fabricating dual-modified layer for lithium-ion batteries
Enhancement on structural stability of Ni-rich cathode materials by in-situ fabricating dual-modified layer for lithium-ion batteries
复制标题
原位制备锂离子电池双改性层增强富镍正极材料的结构稳定性
DOI：
10.1016/j.nanoen.2019.104043
复制
发表时间：
2019-11-01
期刊：
影响因子：
17.6
通讯作者：
Zheng, Jun-chao
中科院分区：
文献类型：
--
作者：
Liu, Yang;Tang, Lin-bo;Zheng, Jun-chao
富镍阴极由于其高的电化学容量和低的成本而被认为是锂离子电池（LIB）的有前途的阴极。然而，富镍阴极在充放电过程中由于界面不稳定和体相结构退化而导致的容量快速衰减严重阻碍了其发展和应用。为了解决这些问题，我们采用一步双修饰的方法在LiNi 0. 8 Co 0. 1 Mn 0. 1 O2表面原位合成了In 2 O3和LiInO 2复合涂层，这两种复合涂层可以协同稳定层状结构并减少锂杂质。双改性LiNi_（0.8）Co_（0.1）Mn_（0.1）O_2材料不仅在1C下表现出优异的循环稳定性，容量保持率约为100%，而且在1000 ℃下表现出良好的循环稳定性。90%，而且还表现出在5C的高倍率下的177.1mAh g（-1）的放电容量，在300次循环后的容量保持率为86.4%。进一步的研究证实，即使在长期循环后，均匀粘附的双功能涂层也可以有效缓解颗粒水平的结构退化和晶间裂纹。研究结果表明，双重改性策略对富镍正极材料性能的改善是可行的，该方法也可应用于其他氧化物正极材料。
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.