Design of Solid Electrolytes to Enable Direct Cathode Recycling in All-Solid-State Lithium Metal Batteries

Abstract

All-solid-state lithium metal batteries are thought to be safer when used in electric vehicles with large powertrains. During the manufacturing of cathodes and separators from solid electrolytes, interphases generated between particulates at high pressure and temperature make deconstructing solid-state batteries exceedingly difficult. Here, I will describe a new approach for creating all-solid state batteries that are readily deconstructed and whereby all components of the battery can be dissociated from the other, enabling direct cathode recycling. Key to our design is the solid electrolyte, which assembled from ion-transporting components that may also be disassembled using a simple solvent-assisted process. Batteries featuring this solid electrolyte operate for hundreds of cycles at EV-relevant C-rates with both LFP and NMC cathodes, showing 80% capacity retention over that timeframe. More importantly, second-life batteries after direct cathode recycling indicate we can recovery 90% of the original capacity from the cathodes and sustain it for hundreds of additional cycles at those rates.