Solid Electrolyte Thin Films and Membranes Using Plasma Processing to Enable High Energy Density Lithium Metal Batteries.

Lithium-ion batteries are the core technology in electric vehicles (EVs). However, safety concerns and low energy density (i.e., limited driving range) hinder widespread EV implementation. High energy density solid-state Li metal batteries promise to double the diving range. But Li dendrite penetration through the solid electrolyte (SE) membrane continues to hamper their development. Moreover, the lack of a scalable SE membrane processing method continues to make market transition impractical. This project focuses on the development of a thin (≤50 μm) Li₇La₃Zr₂O₁₂ (LLZO) SE membrane with a unique grain boundary structure that is advantageous for blocking Li dendrite growth. The grain structure is uniquely formed through high-throughput atmospheric plasma spray (APS) processing which is widely used at scale for corrosive coatings in the automotive and aviation industries. By adopting this method, a scalable approach for SE membranes with desirable performance is realized. In addition, the APS process LLZO membranes are further treated with rapid spray plasma processing (RSPP) to remove Li₂CO₃ from the surface which forms as a result of processing in ambient environments.  The RSPP approach enables the manufacturing of SE membranes without the need for costly dry rooms making market transition feasible and enabling Li metal battery to reach a cost goal of  ≤$70/kWh. 

Commercial Value: A plasma surface cleaning approach that enables the manufacturing of an IP-protected dendrite-suppressing solid electrolyte membrane structure in ambient conditions. An IP licensing opportunity for an alternative solid electrolyte material.