Cellulose-Based Materials and Their Application in Lithium–Sulfur Batteries

Lithium-sulfur (Li-S) batteries are promising candidates for next-generation energy storage due to their high energy density, cost-effectiveness, and environmental friendliness. However, their commercialization is hindered by challenges, such as the polysulfide shuttle effect, lithium dendrite growth, and low electrical conductivity of sulfur cathodes. Cellulose, a natural, renewable, and versatile biopolymer, has emerged as a multifunctional material to address these issues. In anode protection, cellulose-based composites and coatings mitigate dendrite formation and improve lithium-ion diffusion, extending cycle life and enhancing safety. As separators, cellulose materials exhibit high ionic conductivity, thermal stability, and excellent wettability, effectively suppressing the polysulfide shuttle effect and maintaining electrolyte stability. For the cathode, cellulose-derived carbon frameworks and binders improve sulfur loading, conductivity, and active material retention, resulting in higher energy density and cycling stability. This review highlights the diverse roles of cellulose in Li-S batteries, emphasizing its potential to enable sustainable and high-performance energy storage. The integration of cellulose into Li-S systems not only enhances electrochemical performance but also aligns with the goals of green energy technologies. Further advancements in cellulose processing and functionalization could pave the way for its broader application in next-generation battery systems.