Wang Yichao, Li Xin
John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA.
Adv Mater. 2024 Apr;36(15):e2309306. doi: 10.1002/adma.202309306. Epub 2024 Jan 17.
Fast kinetics of solid-state batteries at the device level is not adequately explored to achieve fast charging and discharging. In this work, a leap forward is achieved for fast kinetics in full cells with high cathode loading and areal capacity. This kinetic improvement is achieved by designing a hierarchical structure of electrode composites. In the cathode, the authors' design enables high areal capacities above 3 mAh cm to be stably cycled at high current densities of ≈13-40 mA cm, yielding a C-rate from 5 to 10 C. In the anode, the authors' design breaks the common rule of the negative correlation between critical C-rate and the discharge voltage that is observed in most other anodes. The overall design enables the fast cycling of such batteries for over 4000 cycles at room temperature and 5 C charge-rate. The design principles unveiled by this work help to understand critical kinetic processes in battery devices that limit the fast cycling at high cathode loading and speed up the design of high-performance solid-state batteries.
在器件层面，固态电池的快速动力学尚未得到充分探索以实现快速充放电。在这项工作中，对于具有高阴极负载和面积容量的全电池的快速动力学取得了重大进展。这种动力学的改善是通过设计电极复合材料的分级结构来实现的。在阴极中，作者的设计使得高于3 mAh cm的高面积容量能够在≈13 - 40 mA cm的高电流密度下稳定循环，产生5至10 C的C倍率。在阳极中，作者的设计打破了在大多数其他阳极中观察到的临界C倍率与放电电压之间负相关的普遍规律。整体设计使得此类电池在室温下以5 C充电率能够快速循环超过4000次。这项工作揭示的设计原则有助于理解电池器件中限制高阴极负载下快速循环的关键动力学过程，并加速高性能固态电池的设计。
