Thermal Spray as a Scalable Alternative Processing Route for Solid-State Thin-Film Batteries

Solid-state thin-film batteries (SSTFBs) are attractive for applications where small footprint, safety, long cycle life, and device integration are more important than high absolute capacity. Their fabrication presently remains strongly tied to vacuum-based methods, which provide dense layers but have limitations such as low deposition rates and high costs. This review assesses whether thermal spray approaches can be useful for SSTFB manufacture by examining the characteristics of thermal spraying in relation to battery layer requirements. The discussion summarizes SSTFB materials and conventional processing constraints, focusing on the suitability of thermal spraying based on thermal exposure, kinetic energy, and phase retention. Compatibility is explored for SSTFB anodes, cathodes, solid electrolytes, and current collectors. Recent studies show thermally sprayed constituents can possess electrochemical functionality; however, challenges including ion loss, phase formation, and reproducibility persist. Despite these issues, the review suggests a promising near-term role for thermal spray in fabricating layers and current collectors, with potential for hybrid architectures that synergize with traditional thin-film methods to optimize performance quality.