Preparation and electrochemical characterization of LiCoO_2 single crystal particles prepared by super critical water synthesis (SCWS)

摘要

LiCoO_2 single cyrstal particles were obtained by super critical water synthesis (SCWS) under optimized preparaton conditions. The particle size of the LiCoO_2 was less than 1 um m, which was much smaller than that of LiCoO_2 prepared by a standard method. HOwever, some unknown crystalline and amorphous phases coexisted with the well defined LiCoO_2 single crystal particles. The discharge and charge characteristics of the LiCoO_2 prepared by the SCWS were examined by some electrochemical methods. In the first cycle, an irreversible behavior was observed, and then the gradual decrease of the discharge capacity with discharge and charge cycle was also detected. The stable discharge capacity was estimated to be 80 mA h g~-1 after the 100 th cycle. This result may be due to the existenceof amorphous phases and some structural defects.