Fibrous materials for interface engineering in durable and shape-customizable lithium metal batteries

Lithium metal batteries (LMBs) are considered as one of the promising high-energy batteries for next-generation energy storage devices. However, the potential high performance is plagued by various formidable interfacial problems at different levels and parts. Fibrous materials have the advantages of high aspect ratio, light weight, flexibility, and high surface area, making them promising platforms for addressing the interfacial issues in LMBs. Recent studies show that fibrous materials with vast tunability in structure, property and function can serve as key components of LMBs, such as electrode skeletons, separators, interlayers and so forth. With the rational utilization of fibrous materials, improvement of battery performance and innovation of battery format are both promoted. In this review, from the interface engineering point of view, we discuss the interfacial issues at various battery components including cathode, separator, electrolyte, and anode. The recent progress on rational design and utilization of fibrous materials to solve the interfacial issues is summarized. The fibrous materials for addressing the dendrite growth and penetration, solid-electrolyte-interphase breakage, polysulfide shuttling, and structural instability of cathode are detailed. Finally, the remaining challenges and future research direction for better design and fabrication of fibrous interface materials are discussed and suggested.