| 摘要 |
PURPOSE:To enable the improvement of discharge performance at a high rate and the increase of battery capacity by containing gamma-Cd(OH)2 in the negative electrode active material of a Ni-Cd battery. CONSTITUTION:An alkaline secondary battery comprises a nickel hydroxide positive electrode plate and a cadmium negative electrode plate. In this case, the content of Cd hydroxide in a negative electrode active material is 0.95 times or less Ni hydroxide in a positive electrode active material, and gamma-Cd(OH)2 is contained in the negative electrode active material. The battery equipped with the aforesaid negative electrode plate can maintain the crystal state of gamma-Cd(OH)2 regardless of repeated discharge. As a result, the Cd negative electrode plate always has high charge efficiency and is almost free from Cd hydroxide incapable of being charged. According to the aforesaid construction, it is possible to obtain the stable shift of capacity without any drop in voltage change in a final charging stage. Also, the Cd electrode always has a large active material utilization factor during discharging and low discharge rate dependency and, therefore, the battery becomes excellent in performance at a high discharge rate. |
