Conductive Polymer Overlayer Engineering for Stable Capacity and Durable Si Anodes
발표자
허유민 (한국과학기술연구원)
연구책임자
이영준 (한국과학기술연구원)
공동저자
허유민 (한국과학기술연구원), 이영준 (한국과학기술연구원), 이승훈 (경희대학교)
초록
내용
Micro-sized silicon (Si) particle (SiMP) anodes provide high practical energy density and are compatible with existing lithium (Li)-ion battery (LIB) manufacturing, but they suffer from large volume change and unstable interfaces during cycling. We present a simple, scalable post-coating that applies a water-processable mixture of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) and poly(acrylic acid) as a conductive, compliant overlayer (P:PP) onto pre-fabricated SiMP electrodes. The overlayer helps prevent electrical isolation of Si particles by preserving interparticle electrical contact, thereby improving rate capability and cycling stability. Notably, the P:PP-coated electrode retains >1,600 mAh g-1 after 200 cycles at 2.1A g-1 with an average Coulombic efficiency of 99.19%. Post-cycling morphology shows that deformation and thickness growth are largely confined beneath the overlayer, helping retain surface planarity.