| 摘要 |
PURPOSE:To reduce the mercury quantity by using a derivative or the like made by substituting the terminal functional group of polyoxyethylene alkyl ether with the phosphonic acid group, sulfonic acid group, or methylene carboxylic acid group as a corrosion preventive agent suppressing the corrosion of a negative electrode. CONSTITUTION:Polyethylene alkyl ether RO(CH2CH2O)nPO3H2, RO(CH2CH2O)SO3 H, RO(CH2CH2O)nCH2COOH or a base made by neutralizing this derivative with an alkaline metal is used as a corrosion preventive agent. This corrosion preventive agent can be used by such methods as the addition into an electrolyte 2, the impregnation into a separator 4 and/or a protective material 3, and the adhesion to the surface of a negative electrode active material. The hardening rate of the negative electrode can be reduced accordingly. If this corrosion preventive agent is used concurrently with a corrosion preventive zinc alloy, it is more effective. |
