Binary\nNetwork of Conductive Elastic Polymer Constraining\nNanosilicon for a High-Performance Lithium-Ion Battery

Abstract

Silicon-based anodes are attracting\nmore interest in both science\nand industry due to their high energy density. However, the traditional\npolymeric binder and carbon additive mixture cannot successfully accommodate\nthe huge volume change and maintain good conductivity when cycling.\nHerein, we report a multifunctional polymeric binder (PPTU) synthesized\nby the cross-linking of conducting polymer (PEDOT:PSS) and stretchable\npolymer poly­(ether-thioureas) (PETU). The multifunctional polymeric\nbinder could be curved on the surfaces of nanosilicon particles, forming\nan interweaving continuous three-dimensional network, which is beneficial\nto electron transfer and the mechanical stability. Furthermore, the\nbinder is elastic and adhesive, and which can accommodate the huge\nvolume change of silicon to keep its integrity. Utilizing this multifunctional\npolymeric binder instead of commercial poly­(acrylic acid) binder\nand carbon black mixtures, the nanosilicon anode demonstrates enhanced\ncycling stability (2081 mAhg^–1 after 300 cycles)\nand rate performance (908 mAhg^–1 at 8 Ag^–1). The multifunctional polymeric binder has high conductivity, elasticity,\nand self-healing properties is a promising binder to promote progress\ntoward a high performance lithium-ion battery.