Li Jizhou, Sharma Nikhil, Jiang Zhisen, Yang Yang, Monaco Federico, Xu Zhengrui, Hou Dong, Ratner Daniel, Pianetta Piero, Cloetens Peter, Lin Feng, Zhao Kejie, Liu Yijin
Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA.
School of Mechanical Engineering, Purdue University, West Lafayette, IN 47906, USA.
Science. 2022 Apr 29;376(6592):517-521. doi: 10.1126/science.abm8962. Epub 2022 Apr 28.
Improving composite battery electrodes requires a delicate control of active materials and electrode formulation. The electrochemically active particles fulfill their role as energy exchange reservoirs through interacting with the surrounding conductive network. We formulate a network evolution model to interpret the regulation and equilibration between electrochemical activity and mechanical damage of these particles. Through statistical analysis of thousands of particles using x-ray phase contrast holotomography in a LiNiMnCoO-based cathode, we found that the local network heterogeneity results in asynchronous activities in the early cycles, and subsequently the particle assemblies move toward a synchronous behavior. Our study pinpoints the chemomechanical behavior of individual particles and enables better designs of the conductive network to optimize the utility of all the particles during operation.
改进复合电池电极需要对活性材料和电极配方进行精细控制。电化学活性颗粒通过与周围的导电网络相互作用，发挥其作为能量交换储存库的作用。我们构建了一个网络演化模型，以解释这些颗粒的电化学活性与机械损伤之间的调节和平衡。通过使用基于LiNiMnCoO的阴极中的X射线相衬全息断层扫描对数千个颗粒进行统计分析，我们发现局部网络的不均匀性导致早期循环中的异步活性，随后颗粒组件趋向于同步行为。我们的研究明确了单个颗粒的化学机械行为，并能够更好地设计导电网络，以优化所有颗粒在运行期间的效用。
