Decoupling Ion-Electron Transport in Thick Solid-State Battery Electrodes
Amin Song, Wujiu Zhang, Li Ma, Yicheng Lai, Yaohua Zhao, Jifu Zhu, Mengjie Huang, Lei Wang, Lei Dong, Nan Li, Chao Shen, Keyu Xie
Abstract
Thick electrode architecture, promising better energy storage performance in solid-state batteries (SSBs), requires an optimized ion permeation network design. Unfortunately, ignoring the complex ion-electron coupling, the single ion diffusion optimized array electrodes have an unbalanced energy/power density issue. Hence, a vascularized electrode with a homogeneous electronic/ionic transport network is proposed. By decoupling the ion-electron transport process, a multifactor correlated thick electrode design criterion is established. The competitive effects of space and mass of the active/inactive components are considered for architecture optimization and performance improvement. The optimized LiFeO 4 (LFP) electrode ensures high-rate operation at ultrahigh areal capacity, achieving power densities exceeding 1600 W kg –1 . The solid-state pouch cells exhibit long-term cyclability, providing high energy/power density (approximately 200 Wh kg –1, 687 W kg –1 ) and thermal/mechanical tolerance. Furthermore, bipolar stacking enables pouch cells to have a high voltage and volumetric energy density. This work lays a solid foundation for the commercial application of thick electrodes, illuminating the future of industrial solid-state batteries.