Key points are not available for this paper at this time.
We have investigated the effects of the molecular weight of the polyvinylidene fluoride (PVDF) binder on the electrochemical performance and mechanical integrity of the LiNi0.33Co0.33Mn0.33O2 (NMC) electrodes made by a dry-powder-coating process. The microstructure, binding strength, and electrochemical behavior of the electrodes made with two types of PVDF polymers were compared. We show that a thin PVDF layer can form on the NMC particle surface after heating the PVDF to above its melting point. The microstructure and porosity of the PVDF layer depend strongly on the molecular weight of the PVDFs. With increasing molecular weight, the PVDF layer becomes more porous, improving the high-rate capacity without decreasing binding strength and long-term cycling performance of the electrodes.
Wang et al. (Tue,) studied this question.