Dual-site lattice co-doping strategy regulated crystal-structure and microstructure for enhanced cycling stability of Co-free Ni-rich layered cathode
Lei Liu, Yan Zhao, Guanghui Jiang, Liang Shan, Zelong Yang, Yaoqiang Ma, Yingjie Zhang, Qi Meng, Peng Dong
Abstract
Affected by cobalt (Co) supply bottlenecks and high costs, Co-free Ni-rich layered cathodes are considered the most promising option for economical and sustainable development of lithium-ion batteries (LIBs). Low-cost LiNixAl1−xO2 (x ≥ 0.9) cathode are rarely reported due to their chemo-mechanical instabilities and poor cycle life. Herein, we employ a strategy of Mg/W Li/Ni dual-site co-doping LiNi0.9Al0.1O2 (named as LNA90) cathodes to enhance cycling stability by modifying the crystal structure and forming a center radially aligned microstructure. The Mg/W co-doped LiNi0.9Al0.1O2 cathode (named as LNAMW) exhibits high capacity retention of 94.9% at 1 C and 3.0–4.5 V after 100 cycles with 22.0% increase over the pristine cathode LNA90 and maintains the intact particle morphology. Meanwhile, the cycling performance of LNAMW cathode exceeds that of most reported Ni-rich cathodes (Ni mol% > 80%). Our work offers a straightforward, efficient, and scalable strategy for the future design of Co-free Ni-rich cathodes to facilitate the development of economical lithium-ion batteries.