Poly(methyl methacrylate) Grafted Natural Rubber Binder for Anodes in Lithium-Ion Battery Applications

Binders are one of the crucial components in batteries that provide adhesion for active materials and substrates. However, binders have always been the least studied materials compared with cathodes, anodes, and electrolytes. Here, a semicrystalline poly(methyl methacrylate) grafted natural rubber (MG49) was independently used and studied as a standalone rubber-based binder for graphite-based anode in Li-ion batteries. A comprehensive investigation of physicochemical and electrochemical performances of these electrodes consisting of the MG49 binder was done. The X-ray diffraction analysis found that the MG49-based electrodes showed good crystalline peaks that belong to the graphite compared with PVDF- and SBR + CMC-based electrodes. Similarly, the surface morphology and topography results of MG49-based electrodes and blank SBR + CMC displayed a better distribution of graphite and Super P. This led to an enhanced diffusion coefficient for the optimum electrode and a low charge transfer resistance ( R ct ) of 153.4 Ω, which is comparable to those of SBR + CMC (129.4 Ω) and PVDF (570.5 Ω). Equally, the MG49-based electrode possessed a good reversibility redox reaction and low polarization. The evaluation of battery performance showed good resilient cycling stability and capacity retention (84.7%), and their Coulombic efficiency was maintained at >98.5%, underlying the potential use of MG49 rubber as a binder in Li-ion battery applications.