Vinyltriethoxysilane crosslinked poly(acrylic acid sodium) as a polymeric binder for high performance silicon anodes in lithium ion batteries

Abstract

In order to effectively relieve the large volume changes of silicon anodes during the cycling process in lithium ion batteries (LIBs), we developed a vinyltriethoxysilane crosslinked poly(acrylic acid sodium) polymeric binder (PVTES-NaPAA) for the Si anodes. The PVTES-NaPAA binder was synthesized by using a free radical co-polymerization method with VTES and NaPAA as precursors. In this binder, NaPAA with carboxyl groups can provide strong adhesion between Si particles and the current collector. Furthermore, VTES can be hydrolyzed and condense with each other to form a three-dimensional crosslinked network; the special network makes it possible to improve the Si electrode stability, resulting in an excellent cycling performance (78.2% capacity retention after 100 cycles) and high coulombic efficiency (99.9% after 100 cycles).