Drying Process Research on High Energy Density LiNi1/3Co1/3Mn1/3O2 Electrode in Li-Ion Batteries

Abstract

The most essential parameters in batteries are energy density, cost and safety. The cell energy density depends on the cell chemistry and geometry. In previous research, we made ultra-thick electrodes with optimum energy and power density for electric vehicles (EVs) and hybrid EVs (HEVs). Currently we developed a methodology such that the temperature of the laminates reached the temperature of the drying oven within a minute and drying of thick laminates at rates approaching industry (< 10 min). We examined the role of drying conditions of coated slurries on electrode morphology, binder distribution, binder crystallinity and in turn on the electrode’s mechanical and electrochemical properties. In our research, drying temperature has an impact on the components distribution in the electrode. The crystallinity of binder (poly vinylidene fluoride, PVDF) in the electrode is also dependent on drying temperature. From room temperature to 180 °C, the crystalline phase of PVDF membrane switched from β-phase to α-phase. The ionic conductivity is different in the two phases, which leads to different electrochemical performance of electrodes. Figure 1