Fabrication pressures and stack pressures in solid-state battery

Abstract

Solid-state batteries (SSBs) have received widespread attention with their high safety and high energy density characteristics. However, solid-solid contacts in the internal electrode material and the electrode material/solid electrolyte (SE) interfaces, as well as the severe electrochemo-mechanical effects caused by the internal stress due to the volume change of the active material, these problems hinder ion/electron transport within the SSBs, which significantly deteriorates the electrochemical performance. Applying fabrication pressures and stack pressures are effective measures to improve solid-solid contact and solve electrochemo-mechanical problems. Herein, the influences of different pressures on cathode material, anode material, SEs, and electrode/SEs interface are briefly summarized from the perspective of interface ion diffusion, transmission of electrons and ions in internal particles, current density and ion diffusion kinetics, and the volume changes of Li⁺ stripping/plating based on two physical contact models, and point out the direction for the future research direction of SSBs and advancing industrialization by building the relationship between pressures and SSBs electrochemistry.