Advancements in chitosan membranes for promising secondary batteries

Secondary batteries, or rechargeable batteries, have revolutionized various industries by offering the ability to be reused after depletion. Membranes in secondary batteries act as separators, preventing direct contact between electrodes while facilitating ion transport, crucial for energy storage and preventing short circuits. Despite their theoretical ability to be used infinitely, real-time applications face challenges, including the inefficiency of available membranes. This review focuses on the use of chitosan, a biopolymer derived from chitin, in three promising secondary batteries: vanadium redox flow batteries, Aq. zinc batteries, and lithium-ion batteries due to their wide range of applications and promising future scope. For lithium-ion batteries, N-succinyl chitosan-chitosan and chitosan–lithium membranes offer potential improvements in ionic conductivity and mechanical strength, while in Aq. zinc battery chitosan-based carbon membrane and phosphorylcholine zwitterionic protective layer reduces the dendrite formation and alleviates side reactions and for vanadium redox flow battery chitosan modified batteries aim to reduce vanadium ion crossover. Using a chitosan-based membrane increases the energy efficiency of the vanadium redox flow battery to 88.6% from 60% and sustains an Aq. zinc ion battery for up to 2000 cycles. Comprehensively, this review also imparts a roadmap leading to the future prospects of chitosan biopolymer-based secondary batteries to ameliorate the energy density, and overall electrochemical performance of chitosan-derived batteries by modifying the electrode material, for heading toward a green, and sustainable energy storage system.

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