PFI-TT: Fabrication of Solid Electrolyte Thin Films with Plasma Processing to Enable Solid State Batteries with High Energy Density

Arizona State University, Scottsdale AZ

Investigators

Abstract

The broader impact/commercial potential of this Partnerships for Innovation - Technology Translation (PFI-TT) project is the production of high quality thin films for applications in batteries. The replacement of flammable liquid electrolytes with solid-state electrolytes in next generation batteries will greatly improve the energy density and safety of lithium batteries. However, it is still a challenge to fabricate high performance solid-state batteries using commercially viable manufacturing processes. The outcome of this project will be the development a new scalable process for fabrication of novel materials for solid-state batteries. The proposed technology derives strengths from chip manufacturing techniques and will enable batteries with improved safety characteristics and energy density compared to the state-of-the-art lithium-ion batteries. The impact of the technology will be accelerated commercialization of the next generation of batteries for electric vehicles, drones, power electronics, and other energy storage applications. The proposed project will develop a novel deposition method that will enable high quality thin films of lithium conducting solid electrolyte, Li7La3Zr2O12 (LLZO), to be grown directly on substrates and electrodes. Among the solid-state electrolytes being considered for all-solid-state batteries, LLZO is one of the most attractive due to its high ionic conductivity and good thermal and electrochemical stability. However, the inability to reliably form LLZO thin films with existing physical/chemical vapor deposition methods or conventional ceramics processing is a major obstacle to the commercialization of LLZO-based solid-state batteries. The innovation is in using plasma-based methods for the production of high quality LLZO thin films with low interfacial resistance and a grain microstructure that is expected to mitigate lithium dendrite penetration. The research will identify optimal process parameters for the film deposition and surface treatments and establish relationships between the LLZO film quality and mechanical and electrochemical properties. Through a close collaboration combining expertise in LLZO materials synthesis, plasma processing, and commercialization of battery ceramic materials and manufacturing processes, knowledge gaps related to the correlations between LLZO thin film growth conditions, device performance, and commercial viability will be bridged. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.