Performance improvement of poly(acrylic acid) binder-based silicon/graphite composite anodes by room temperature electron beam irradiation-induced crosslinking

In this study, we demonstrated that the enhanced performance of poly(acrylic acid) binder-based silicon/graphite composite anode (c-PAA-Si/C) can be achieved by a quick, scalable, and solid-state electron beam irradiation-induced crosslinking in the presence of methylenebisacrylamide (MBA) as a water-soluble crosslinker. The result from analysis of an irradiated PAA binder film revealed that the PAA was completely crosslinked by the electron beam irradiation at the absorbed dose of 30 kGy in the presence of 10 wt% MBA, thereby leading to the much reduced swelling degree and improved tensile strength. Likewise, the c-PAA-Si/C-30 anode (irradiated at absorbed dose of 30 kGy) possessed higher hardness than the non-irradiated PAA-Si/C-0 probably due to the effective formation of the crosslinked structure. Moreover, based on the coin-type half cell performance and cycle stability test, the c-PAA-Si/C-30 anode-based cell exhibited the better retention capacity at 100 cycles than that of the PAA-Si/C-0-based one. The EIS and FE-SEM results showed that this better cycling performance could be ascribed to the crosslinked structure-induced structural stability.