Structural design strategies of polymer binders for silicon-based anodes in lithium-ion batteries

Silicon (Si) anodes have emerged as promising candidates for next-generation lithium-ion batteries (LIBs) owing to their high theoretical capacity. However, their practical application is hindered by severe volume expansion and unstable electrode interfaces during cycling. Polymer binders play a critical role in mitigating these issues by maintaining electrode integrity and enhancing interfacial stability. This review provides a systematic classification of polymer binders for Si-based anodes according to their binding mechanisms, including covalent, hydrogen-bonding, and supramolecular interactions. The discussion emphasizes how structural configurations, such as linear, branched, and cross-linked architectures affect mechanical resilience, adhesion strength, and compatibility with high-loading electrodes. Recent advances in multifunctional and dynamic cross-linked binders are highlighted, with particular focus on strategies to accommodate large volume changes and suppress interfacial degradation. In addition, a comparative analysis of advantages and limitations for various binder systems is provided, along with perspectives on future development trends. This work aims to guide the rational design of polymer binders for achieving stable, high-energy-density Si-based anodes.