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

Abstract

Bipolar all solid-state batteries (ASSBs) represent an innovative battery architecture that attract 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 employment of solid-state electrolytes (SEs) not only addresses the thermal runaway issues associated with routine liquid electrolytes but also expands the operational temperature range of the working batteries. This review systematically explores the optimization processes from model cell design to Ah-level pouch cells fabrication, emphasizing the direct correlation between process optimization and energy density enhancement. It also affords a detailed discussion on the current research advancements in bipolar ASSBs, including SEs with high ionic conductivity, stable electrodes, and interfacial engineering. Furthermore, it outlooks future perspectives on the application prospects in electrical vehicles, energy storage systems, and flexible wearable devices. The rapid development of artificial intelligence accelerates the optimization processes 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 in next-generation energy storage ecosystems.