Fast Kinetics Design for Solid State Battery Device.

Fast kinetics of solid state batteries at the device level have not been adequately explored to achieve fast charging and discharging. In this work, a leap forward has been achieved for fast kinetics in full cells with high cathode loading and areal capacity. This kinetic improvement was achieved by designing a hierarchical structure of electrode composites. In the cathode, our design enables high areal capacities above 3 mAh/cm 2 to be stably cycled at high current densities of 13 ∼ 40 mA/cm 2 , yielding a C-rate from 5C to 10C. In the anode, our 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 4,000 cycles at room temperature and 5C 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. This article is protected by copyright. All rights reserved.