Dongye Liu, Yin Zhao, Linyao Dong, Liaona She, Xu Fei Xue, Xiangrong Ren, Zhijun Wu, Shengnan He, Chao Zheng, Jiantuo Gan, Chenchen Li, Mingchang Zhang, Yaxiong Yang, Yanxia Liu, Wubin Du, Fulai Qi, Mingxia Gao, Hongge Pan
Lithium-rich manganese-based oxides (LRMOs) exhibit high specific capacity exceeding 250 mAh g –1, making them promising candidates for next-generation lithium-ion batteries. However, oxygen evolution during cycling destabilizes the crystal structure, leading to capacity fading. By precisely controlling the oxygen/nitrogen (O 2 /N 2 ) ratio during sintering, this work achieves a significant reduction in bulk oxygen vacancy content and enhances lattice oxygen stability. The O50 sample sintered under 50%O 2 /50%N 2 atmosphere ratio demonstrates exceptional performance with 96.7% capacity retention (216.5 mAh g –1 ) after 300 cycles at 1 C rate (1 C = 200 mA g –1 ). Remarkably, it maintains delivering 155.0 mAh g –1 at 5 C and 133.2 mAh g –1 at 10 C, showing superior rate capability. Structural characterization reveals this atmosphere-controlled sintering strategy simultaneously enhances bulk oxygen stability and surface oxygen vacancy generation, providing a simple yet effective strategy for the design of high-performance LRMOs.