Advances in fibrous materials for high-capacity lithium sulfur batteries

The lithium sulfur battery (LSB) has emerged as a promising next-generation energy storage alternative due to its significantly higher theoretical energy density and lower cost compared to modern Lithium-ion technology. However, the sluggish sulfur redox kinetics, detrimental "shuttle effect" of polysulfides, and degradation of the Li anode impose limitations on the practical applications of LSBs, particularly during long cycle durations, and under high sulfur loading and lean electrolyte conditions. Therefore, many researchers in both industry and academia are actively striving to enhance the energy density and longevity of highly sulfur loaded LSBs. Among different approaches, the incorporation of fibers in LSBs has proven promising. The unique architecture and properties of one-dimensional fibers alleviates the fundamental challenges of LSBs and allows for reasonably high sulfur loadings. This review systematically surveys the technological development of multifarious fibrous materials, and their modification aimed at achieving well engineered cathodes, separators, interlayers and anodes for high-sulfur loading LSBs, with specific consideration given to the areal sulfur mass exceeding 4 mg cm−2. Additionally, a perspective on the future opportunities of fibrous materials for LSBs is presented. The discussions and proposed directions aim to shed light on the rational design of fibrous structures for practical LSBs in the near future.