@article{Guo2022, 
author = {Fangya Guo and Yongfan Xie and Youxiang Zhang},
title = {Tuning Li-excess to optimize Ni/Li exchange and improve stability of structure in LiNi0.8Co0.1Mn0.1O2 cathode material for lithium-ion batteries},
year = {2022},
journal = {Nano Research},
volume = {15},
number = {10},
pages = {8962-8971},
keywords = {cycling stability, structural stability, Ni-rich cathodes, Ni/Li exchange, Li-excess},
url = {https://www.sciopen.com/article/10.1007/s12274-022-4532-y},
doi = {10.1007/s12274-022-4532-y},
abstract = {Ni/Li exchange is a detrimental effect on electrochemical performances for high-Ni cathode materials (LiNixCoyMnzO2, x ≥ 0.6). Adjusting Li-excess degree has been proved to be an effective way to optimize Ni/Li exchange in the materials. However, until now, how the Ni/Li exchange and thus the structural properties is affected by the Li-excess has not been understood and clearly elucidated in the literature. Herein, a feasible strategy is utilized to optimize Ni/Li exchange and the amount of anti-Li+ in LiNi0.8Co0.1Mn0.1O2 by mixing Ni0.8Co0.1Mn0.1(OH)2 precursor with different amounts of lithium sources during lithiation. It was found that morphology and phase stability of the material can be tuned with moderate excessive lithium. With 10% Li-excess, LiNi0.8Co0.1Mn0.1O2 exhibits an initial discharge capacity of 211.5 mAh·g–1 at 0.1 C and maintains 93.3% of its initial capacity after 100 cycles at 1 C. Different technologies were used to characterize the materials and it shows that the formation of broader Li slab space, decreased anti-Ni2+ in Li layer, and gradient distribution of Ni3+ in the surface is contributed to moderate Li-excess in the materials. Broader Li slab space facilitates diffusion of Li+, decreased antisite-Ni2+ and gradient distribution of Ni3+ in materials surfaces optimizes the Ni/Li exchange. Based on these results, we thus believe that it is the moderate Li-excess in material that optimized the electrochemical performance of high-Ni cathode materials.}
}