New process for low temperature preparation of LiNi1-xCoxO2 cathode material for lithium cells

摘要

LiNi1-yCoyO2 has been prepared at a temperature as low as 400 degrees C by molten ion exchange using a beta Ni1-yCoyOOH and either LiNO3 or LIOH. The mechanism of these reactions was clarified using DTA and TG analyses. The material prepared using the LiNO3 is well crystallized because the reaction takes place in viscous state since LiNO3 melts and then reacts with the oxyhydroxide. However, in the case of using LiOH, a solid-solid diffusion reaction takes place and leads to a material with broad XRD peaks. The electrochemical characteristics of these materials were evaluated and compared with those prepared by the usual processes at high temperature. [References: 6]