From mold to Ah level pouch cell design: bipolar all-solid-state Li battery as an emerging configuration with very high energy density

Abstract

Bipolar all-solid-state batteries (ASSBs) represent an innovative battery architecture and have attracted significant attention due to their high energy density, enhanced safety, and simplified packaging design. These batteries effectively reduce the use of inactive materials, thereby increasing volumetric energy density through the integration of bipolar electrode architecture with the advantages of solid-state technology. The use of solid-state electrolytes (SEs) not only addresses thermal runaway issues associated with routine liquid electrolytes but also expands the operational temperature range of working batteries. This review systematically explores the optimization processes from model cell design to Ah-level pouch cell fabrication, emphasizing the direct correlation between process optimization and energy density enhancement. It also provides a detailed discussion on the current research advancements in bipolar ASSBs, including SEs with high ionic conductivity, stable electrodes, and interfacial engineering. Furthermore, it outlines future perspectives on application prospects in electric vehicles, energy storage systems, and flexible wearable devices. The rapid development of artificial intelligence accelerates the optimization of bipolar ASSBs. As bipolar ASSBs achieve higher energy densities while maintaining safety and long-term cycling stability, they are poised to become a transformative technology for next-generation energy storage ecosystems.