Spray drying of spherical Li4Ti5O12/C powders using polyvinyl pyrrolidone as binder and carbon source

Polyvinyl pyrrolidone (PVP) was used as binder and carbon source to synthesize stable and spherical Li4Ti5O12/C granules by spray drying. The effects of PVP content and atmospheres on the properties of Li4Ti5O12 were investigated. The obtained samples were characterized by X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and electrochemical tests, respectively. The results indicate that the average particle size, tap density and degree of spherical structure increase accordingly to the increase of PVP content. However, the large secondary particle would deteriorate the rate capacity at high current density. The carbon coating could significantly improve the rate capacity, which is attributed to the smaller primary particle and higher electrical conductivity.