AMORPHOUS MOS2 AS THE CATHODE OF LITHIUM SECONDARY BATTERIES

Amorphous MoS2(a-MoS2) was synthesized by the thermal decomposition of (NH4)(2)MoS4 in a hydrogen gas flow at temperatures from 150 to 300 degrees C. The a-MoS2 synthesized at 150 and 200 degrees C were almost amorphous. However, those prepared at 250 and 300 degrees C showed very small and broad peaks in powder X-ray diffraction patterns. Discharge/charge cycling measurements, revealed that the sample prepared at 150 degrees C showed the highest cycle capacity (100 Ah/kg) at the 100th cycle. The chemical diffusion coefficients of lithium were also highest for a-MoS2 prepared at 150 degrees C, and the ($) over bar D values fell in the range of -10<log(($) over bar D/cm(2) s(-1))<-9.