期刊

Tungsten

标题

Engineering layered/spinel heterostructure via molybdenum doping towards highly stable Li-rich cathodes

作者

Kun-Qi Geng, Meng-Qian Yang, Jun-Xia Meng, Ling-Fei Zhou, Yu-Qin Wang, Sydorov Dmytro, Qian Zhang, Sheng-Wen Zhong & Quan-Xin Ma 

摘要

Li-rich layered oxide (LLO), e.g., Li1.12[Mn0.56Ni0.16Co0.08]O2 (LRMO), is considered as a promising cathode material due to its superior Li-storage capability. However, the poor cycling stability and large voltage decay, which are related to the phase transition, limit its industrialization process. Herein, a Mo-doped LRMO (Li1.12[Mn0.56Ni0.16Co0.08]0.98Mo0.02O2, LRMO-Mo2.0%) was successfully synthesized via a simple combination of co-precipitation with high-temperature calcination for solving the mentioned above- disadvantages. Compared with the pristine counterpart, the as-prepared LRMO-Mo2.0% shows more excellent electrochemical performance in terms of rate capability (reversible capacity of 118 mA·h·g−1 at 5 C), cyclic ability (94.3% capacity retention after 100 cycles at 0.2 C) and discharge midpoint voltage decay (0.11 V after 100 cycles). Systematic investigation of structural evolution and electrochemical kinetics elucidate that the synergic effect of robust oxygen framework and layered/spinel heterostructure is the key to its performance improvement. Such synergy helps to stabilize the layered structure by curbing the structural transformation and oxygen escaping during the electrochemical cycling. This work paved the way for the simple and efficient preparation of highly stable LLO cathode materials.

原文链接

https://link.springer.com/journal/42864/volumes-and-issues/4-4