Engineering Multifunctional Binders for Micro-Silicon Anodes: Mechanisms, Strategies, and Applications

Silicon-based anode materials are widely regarded as promising candidates for next-generation lithium-ion batteries owing to their high theoretical specific capacity (3579 mAh g^-1) and natural abundance. Among these, micro-sized silicon (micro-Si) offers superior commercial viability compared to nano-Si due to its lower production costs and higher tap density. However, micro-Si electrodes encounter critical challenges during cycling, such as severe stress concentration, lithium trapping, and unstable solid electrolyte interphase (SEI) formation. Binders, acting as structural and electrochemical regulators, play a pivotal role in addressing these limitations; however, systematic evaluations of functional binders tailored for micro-Si remain scarce. This review compares the advantages and limitations of nano-Si and micro-Si, highlighting the industrial potential of micro-Si and elucidating its distinct degradation mechanisms. State-of-the-art binder design strategies for micro-Si anodes and current advances in their practical applications are then reviewed. Finally, future perspectives are discussed, emphasizing the importance of binder innovation in enabling the commercial deployment of micro-Si anodes.