Preparation of Water-Resistant Surface Coated High-Voltage LiNi0.5Mn1.5O4 Cathode and Its Cathode Performance to Apply a Water-Based Hybrid Polymer Binder to Li-Ion Batteries

• DOI: 10.1016/j.electacta.2016.12.064
• Publication Date: 2016-12-15T12:24:48Z
• Authors: Toyokazu Tanabe; Takao Gunji; Youhei Honma; Koki Miyamoto; Takashi Tsuda; Yasumasa Mochizuki; Shingo Kaneko; Shinsaku Ugawa; Hojin Lee; Takeo Ohsaka; Futoshi Matsumoto
• Keywords: 02 engineering and technology; 0210 nano-technology; 01 natural sciences; 0104 chemical sciences

Abstract Water-resistant LiNi 0.5 Mn 1.5 O 2 spinel cathode was prepared by surface coating with carbon, Al 2 O 3 and Nb 2 O 5 to use a water-based hybrid polymer (TRD202A, JSR, Japan) as a binder and to form the cathode film on an Al current collector. The surface composition and degree of the surface coverage of carbon, Al 2 O 3 and Nb 2 O 5 were characterized with field-emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The coated LiNi 0.5 Mn 1.5 O 2 particles not only exhibited water-resistant property but also showed no decrease in discharge capacity and only a small degradation of discharge rate performance. In addition, the coated LiNi 0.5 Mn 1.5 O 2 particles, that were exposed to water-based binder solution for one week, exhibited the same charge/discharge cycle performance as observed for the cathode of the pristine LiNi 0.5 Mn 1.5 O 4 particles, suggesting that the coated particles are promising as cathode materials with a water-resistant property and therefore water can be used as solvent for preparing the cathode slurry solution in the place of e.g., carcinogenic N-methyl-2-pyrrolidone which is used actually.