A Stress Self‐Adaptive Structure to Suppress the Chemo‐mechanical Degradation for High Rate and Ultralong Cycle Life Sodium Ion Batteries.

Liu, Yiming; Wang, Jing; Shi, Qinhao; Yan, Mouhui; Zhao, Shengyu; Feng, Wuliang; Qi, Ruijuan; Xu, Jiaqiang; Luo, Jiayan; Zhang, Jiujun; Zhao, Yufeng

Transition‐metal phosphides (TMPs) as typical conversion‐type anode materials demonstrate extraordinary theoretical charge storage capacity for sodium ion batteries, but the unavoidable volume expansion and irreversible capacity loss upon cycling represent their long‐standing limitations. Herein we report a stress self‐adaptive structure with ultrafine FeP nanodots embedded in dense carbon microplates skeleton (FeP@CMS) via the spatial confinement of carbon quantum dots (CQDs). Such an architecture delivers a record high specific capacity (778 mAh g−1 at 0.05 A g−1) and ultra‐long cycle stability (87.6 % capacity retention after 10 000 cycles at 20 A g−1), which outperform the state‐of‐the‐art literature. We decode the fundamental reasons for this unprecedented performance, that such an architecture allows the spontaneous stress transfer from FeP nanodots to the surrounding carbon matrix, thus overcomes the intrinsic chemo‐mechanical degradation of metal phosphides.

SODIUM ions; QUANTUM dots; STORAGE batteries; PHOSPHIDES; MICROPLATES

Angewandte Chemie, 2023, Vol 135, Issue 29, p1

0044-8249

Academic Journal

10.1002/ange.202303875