Enhancement and architectural optimization of polyvinylidene fluoride-based solid polymer electrolytes for advanced solid-state lithium-metal batteries

Energy storage devices have become an integral aspect of both industrial production and everyday life, with the rapidly escalating demand for batteries that possess high energy-density and robust safety features. This paper delves into the inherent properties of diverse solid-state electrolytes (SSEs) employed in solid-state lithium-metal batteries (SSLMBs), which are distinguished by their high energy-density, with the objective of assessing their suitability for application in SSLMBs. Among the various types of SSEs, polyvinylidene fluoride (PVDF)-based solid polymer electrolytes (SPEs) emerge as one of the most promising candidates, which has received much attention for its wide electrochemical window, good thermal and chemical stability, and ability to be better adapted to lithium-metal anode. Furthermore, optimizing the ionic conductivity of the SSEs, improving the wettability at the electrode/electrolyte interface, and effectively mitigating the growth of lithium dendrites are crucial for enhancing the performance of SSLMBs with high energy-density. Therefore, this paper reviews and analyzes the modification and structural design of PVDF-based SPEs from various aspects, and summarizes the methods to overcome the inherent defects of PVDF-based SPEs and improve their performance. Finally, based on existing literature, this paper provides an outlook on the research directions for the application of PVDF-based SPEs in SSLMBs. This review focuses on Polyvinylidene Fluoride (PVDF)-based polymer electrolytes with more balanced ion conductivity, chemical stability, electrochemical stability, and plasticity, and explores their structural characteristics and key challenges in solid-state lithium metal battery applications in depth. The current research methods for PVDF-based polymer electrolytes are comprehensively summarized, and three types of modification methods and three structural design strategies are introduced. • The bottleneck in the development of high-performance SSLMBs is put forward. • The characteristics of PVDF based SPEs is explored in depth. • A comprehensive analysis and summary of the modification strategies are conducted. • Structural designs for PVDF-based solid polymer electrolytes are conducted. • Providing forward-looking suggestions for the development of PVDF-based SPEs.