| 摘要 |
PURPOSE:To improve the initial performance and life performance by kneading lead powder added with graphite having large anisotropy with an aqueous dispersion liquid of water, dilute sulfuric acid, and synthetic resin and filling it into a lattice body. CONSTITUTION:Natural graphite is heat-treated into graphite having large anisotropy and lead powder is added to it and mixed. Next, it is fully kneaded with water and dilute sulfuric acid, and an aqueous dispersion liquid of epoxy resin, etc. is added to it and kneaded to produce paste, which is then filled into a lead alloy lattice to form a positive electrode through maturing and formation processes. Accordingly, even a positive electrode active material having a large paste density can improve the initial performance with an increase of porosity because of the characteristics that graphite having large anisotropy bulges in the C-axis direction of the crystal when the positive electrode is oxidized, and also the active material is prevented from being softened or peeled off due to the net structure of synthetic resin, thereby the life performance can be improved. |
