Silver oxide producing process for battery

Abstract

An aqueous sodium carbonate solution is added in an equivalent amount to an aqueous silver nitrate solution (Ag = 100 g / L) under stirring and, with nitric acid and sodium hydroxide being added to adjust the pH to 5.5-6.5, a silver carbonate precipitate is formed and subsequently washed thoroughly and dried at 250 DEG C or below to produce a silver oxide powder, which satisfactory characteristics for use in cells, as exemplified by high water absorption, good shape of granules, high strength, non-stickiness to the molding punch, high fluidity and low residual carbon content. The pellet of the powder has high cell capacity.

Description

[0001] This application is a divisional application, the parent application number is 97126294.2, the application date is November 7, 1997, and the invention name is "silver oxide for batteries and its manufacturing process". field of invention [0002] The invention relates to silver oxide used as a positive electrode active material in a silver oxide battery, its manufacturing process and a primary battery using the silver oxide as a positive electrode active material. Background technique [0003] The prior art in this field has the following references: Unexamined Japanese Patent Application Publication Nos. 53219 / 1973, 53221 / 1973 and 53222 / 1973, which specify the pore volume per unit volume of silver oxide positive electrode active material and its battery density; Examined Japanese Patent Application Publication No. 111956 / 1982 shows the effectiveness of porous silver oxide on discharge performance; Unexamined Japanese Patent Application Publication No. 51469 / 1983 shows...

AI Technical Summary

Problems solved by technology

[0004] These patents respectively record the expected characteristics of silver oxide for batteries; however, none of the silver oxides proposed in these patents can meet all the characteristic requirements alone, and there are the following disadvantages:

[0005] (1) When using porous silver oxide, if an organic binder is used to improve the discharge performance, the pores in the silver oxide particles are blocked by the binder, and the characteristics of the porous silver oxide cannot be fully displayed;

[0006] (2) If the addition amount of the binder is reduced, the particle strength decreases so much that the handling in the molding step causes fracture, and the fluidity of the powder eventually changes, resulting in deterioration of its meterability;

[0007] (3) The traditional silver oxide powder has no regulation on the size of the primary particles, and because it contains fine particles (≤5μm), it needs to clean the tableting mold during the molding process or because it adheres to the punch, so it is not suitable for mass production. Unfavorable efficiency

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