The Polymer Society of Korea

Abstract

To improve the energy density of lithium-ion batteries, the development of thick cathodes is essential. However, slurry-based fabrication processes often result in inhomogeneous particle distribution due to solvent evaporation. Additionally, insufficient ionic conductivity within the electrode can lead to performance degradation under high current densities. In this study, a solvent-free dry-coating process was employed to fabricate thick cathodes. To enhance lithium-ion mobility within the electrode, a strategy to reduce binder crystallinity was implemented. Quenched poly(vinylidene fluoride) (PVDF) was initially used as a binder, but this method required an additional quenching step in the process. To address this limitation, succinonitrile (SN), known for its high ionic conductivity, was introduced as an additive. SN not only improved ionic conductivity but also acted as a plasticizer. As a result, the SN-containing PVDF binder exhibited lower crystallinity than quenched PVDF, leading to enhanced lithium-ion transport.