Abstract: We find that after heat treatment, the utilization ratio of CuO increases. When the heating temperature is 700℃, the ratio is about 38% higher than that of the unheated CuO. The result shows that heated CuO is able to improve the electrochemical performance of the Li-CuO cells. Experiments with X-ray diffraction, differential thermal analysis and electronic scanning microscopy etc. reveal that after the 700℃ treatment, no new phases take place, but the grains become a little bit smaller and their shape changes slightly.