LiCoPO4 based cathodes have been investigated in matter of electrochemical performance and thermal stability. The two-step characteristic of the charging process of LiCoPO4 cathodes is clearly illustrated. Investigations on the thermal stability of the partially delithiated and the fully delithiated cathode were performed by using simultaneous DSC-TG-MS. While the partially delithiated cathode shows a high thermal stability, the fully charged cathode decomposes between 160 and 260 °C. Furthermore, the influence of electrolyte, carbon coating and conductive additives on the decomposition temperature is discussed as well as the influence of the crystallite size of LiCoPO4.