Xerion and project partner researchers reveal that the cathode-electrolyte interface is a critical and poorly understood driver of solid-state battery performance, with dense electrodeposited cathodes emerging as a key solution
Interfaces have crucial, but still poorly understood, roles in the performance of secondary solid-state batteries. Here, usingcrystallographically oriented and highly faceted thick cathodes, we directly assess the impact of cathode crystallography andmorphology on the long-term performance of solid-state batteries. The controlled interface crystallography, area and microstructure of these cathodes enables an understanding of interface instabilities unknown (hidden) in conventional thin-film andcomposite solid-state electrodes. A generic and direct correlation between cell performance and interface stability is revealedfor a variety of both lithium- and sodium-based cathodes and solid electrolytes. Our findings highlight that minimizing interfacial area, rather than its expansion as is the case in conventional composite cathodes, is key to both understanding the natureof interface instabilities and improving cell performance. Our findings also point to the use of dense and thick cathodes as a wayof increasing the energy density and stability of solid-state batteries
