The Polymer Society of Korea

Abstract

Silicon (Si) is a promising anode material for lithium-ion batteries due to its high energy density, yet its severe volume expansion during cycling leads to rapid capacity degradation. In this work, acrylic binders with different side-chain structures were synthesized, copolymerized with methyl methacrylate and methacrylic acid, and blended with carboxymethyl cellulose (CMC) for application in silicon anode half-cells (1 mAh cm⁻²). The electrochemical performance was strongly dependent on the side-chain architecture and mechanical properties of the binders. Among the evaluated systems, the EHA/CMC binder exhibited superior adhesion and stress dissipation compared to conventional SBR/CMC, achieving an initial Coulombic efficiency of 87.00% and a capacity retention of 83.37% after 100 cycles.