An Advanced 3D Crosslinked Conductive Binder for Silicon Anodes: Leveraging Glycerol Chemistry for Superior Lithium-Ion Battery Performance

Angew Chem Int Ed Engl. 2024 Nov 29:e202418794. doi: 10.1002/anie.202418794. Online ahead of print.

Abstract

Silicon (Si) anodes hold great promise for high-capacity lithium-ion batteries (LIBs), yet their practical application is hindered by severe volume expansion and mechanical degradation. To tackle these challenges, we present an innovative 3D crosslinked conductive polyoxadiazole (POD) binder engineered with glycerol (GL) to form a robust network of covalent and hydrogen bonds. This unique chemical architecture not only enhances adhesion and mechanical resilience to effectively dissipate the stresses induced by Si's volumetric changes but also constructs a robust conductive framework to facilitate electron transfer. The dynamic interplay between strong covalent and flexible hydrogen bonds in the POD-c-GL binder enables superior structural integrity and stable solid-electrolyte interphase (SEI) during cycling. The Si@POD-c-GL anode exhibits remarkable electrochemical performance, including a high initial Coulombic efficiency, impressive rate capability, and outstanding cycling stability, with an extremely low-capacity decay rate of 0.022% per cycle for 1000 cycles. This work highlights the potential of harnessing in-situ crosslinking chemistry to develop advanced binders, paving the way for the next generation of high-performance silicon anodes in LIBs.

Keywords: 3D crosslinking chemistry; lithium-ion batteries; polymer binder; silicon anode; stress dissipation.