Partially Carbonized Polymer Binder with Polymer Dots for Silicon Anodes in Lithium-Ion Batteries

Small. 2023 Jan;19(2):e2205065. doi: 10.1002/smll.202205065. Epub 2022 Nov 20.

Abstract

Large-scale applications of conventional conductive binders for silicon (Si) anodes are challenging to accomplish due to their complex synthesis steps and high cost. Herein, a carbonized polymer dots-assisted polyvinyl alcohol-chitosan (PVA-CS-CPDs) binder is developed through a simple and low-cost hydrothermal method. Through rational design, the PVA-CS-CPDs binder retains rich polar groups while forming conjugated structures. The conjugated structure endows the PVA-CS-CPDs with high electronic conductivity, and the retained polar groups maintain strong binding strength. The proposed water-soluble binding system acts as both a binder and conductive additive, enabling stable cycling for high-Si-content (90 wt.%) anodes without any other conductive additives.

Keywords: adhesion; carbonized polymer dots; conductive binders; electronic conductivity; silicon anodes.