Tianxiao Sun, Guannan Qian, Ruqing Fang, Guibin Zan, Zhichen Xue, Stephen E. Trask, Arturo Gutierrez, Wenlong Li, Shimao Deng, Luxi Li, Wenbing Yun, P. Pianetta, Guihua Yu, Jason R. Croy, William C. Chueh, Juner Zhu, Yijin Liu
Rechargeable batteries using electrodes based on intercalation chemistry exhibit notable cyclability, yet their performance still suffers from chemomechanical degradation. In this study, by combining a suite of operando microscopy methods, we explored electrode strain evolution and observed intricate particle cluster rearrangement under electrochemical stimuli. We show that early-stage strain accumulation in intercalation cathodes occurs during the period of interparticle charge transfer and redox reactions stemming from asynchronous coupling and decoupling between chemical (de)intercalation and physical grain motion. This interplay drives heterogeneous redox activity, localized charge equilibration, and multiscale strain cascades that propagate through an asynchronous network of chemical-mechanical interactions. Together, these findings reveal how collective particle dynamics and hierarchical strain transmission dictate electrode deformation and degradation in intercalation cathodes.