The Interaction and Performance of Boron-Based Self-Healing Binders in Silicon Anodes
Tamara Patranika
Uppsala University
Silicon is a promising active material for Li-ion batteries, but it faces challenges with volume changes during cycling, limiting the capacity. To address this, we propose a self-healing polymeric binder using dynamic covalent bonds via boronic esters to enhance the cycling stability of Si anodes. Poly(vinyl alcohol) (PVA) cross-linked with 1,4-benzenediboronic acid (BDBA) showed improved performance and less degradation compared to PVA alone. Solid-state NMR revealed changes in the boron environment in the presence of Si, suggesting an interaction between Si and the binder. However, this interaction does not improve the electrochemical performance with styrene-butadiene rubber, which lacks hydroxyl groups, or with carboxymethyl cellulose, despite having hydroxyl groups. Overall, the interaction between BDBA and PVA enhances performance, making it a promising approach for integrating Si in Li-ion anodes.
