PVDF-based solid polymer electrolytes for lithium-ion batteries: strategies in composites, blends, dielectric engineering, and machine learning approaches

Solid polymer electrolytes (SPEs) present a viable alternative to organic carbonates typically used as liquid electrolytes in lithium-ion batteries (LIBs). Among various SPEs, poly(vinylidene fluoride) (PVDF)-based SPEs have received significant attention owing to their excellent film forming ability, chemical and thermal stability, mechanical strength, and electrochemical performance. This review focuses on recent innovative strategies in composites, blends, and dielectric engineering to achieve PVDF-based SPEs with enhanced electrochemical performance. It is divided into four primary sections: (1) PVDF-based composite electrolytes, which explores the role of inorganic fillers and nanomaterials in improving ionic conductivity and mechanical properties; (2) PVDF-based blend electrolytes, highlighting the role of polymer blending in optimizing crystallinity, flexibility, and ion transport; (3) dielectric engineering, describing various strategies of manipulating the dielectric properties of PVDF-based SPEs to achieve optimized electrochemical performance; and (4) the emerging role of machine learning (ML) techniques in accelerating the discovery and optimization of SPEs materials by predicting performance and guiding experimental design. Finally, the review concludes with future perspectives and challenges, outlining the potential of PVDF-based SPEs to address current limitations and pave the way for next-generation energy storage applications.