| 摘要 |
PURPOSE:To enhance the light-load discharge performance, as well as to reduce the cost of a dry cell, by mixing a carbon black having both a given apparent specific gravity and a given specific surface area with coarse grains of manganese dioxide having a given specific surface area into a positive mixture. CONSTITUTION:A positive mixture 1 is prepared by mixing an active material made of coarse grains of manganese dioxide having a specific surface area of below 50m<2>/g, with a conductive assistant made of a carbon black having an apparent specific gravity of 0.05-0.07 and a specific surface area of 500-800m<2>/g. The carbon black which is used for the above positive mixture 1 is available at an extremely lower price than acetylene black which has been conventionally used. Owing to the above constitution, the electrolyte-holding ability of the entire positive mixture is enhanced, and the packing density of the manganese dioxide is increased. Accordingly, the light-load discharge performance of a dry cell can be enhanced, and the manufacturing cost of the cell can be reduced. |
