| 摘要 |
PURPOSE: To prevent the lowering of capacity in the preservation condition at a high temperature for a long time by arranging a micro capsule 7, of which seal is broken at the predetermined temperature so as to emit the manganese compound, with an electrode group. CONSTITUTION: An electrode group 1 formed by winding a band-shape layered product, which is formed of a positive electrode 1a mainly composed of nickel oxide and cobalt oxide group and a separator 1b and a negative electrode 1c mainly composed of hydrogen storage alloy, is wound so as to form, is housed in a case 2 with the alkali electrolyte so as to form a battery. At this stage, a micro capsule 7, in which potassium permanganate powder is sealed, is arranged at a center space of the electrode group 1. The micro capsule sealing material is made of, for example, a film of nylon 6-66-610-12 copolymer at 150μm of thickness, and the melting point is set at 87-89 deg.C. After the first charging, the battery is maintained at 100 deg.C for 15 minutes so as to break the seal of the micro capsule, and the potassium permanganate is eluted so as to restrict the reduction of tri-valent cobalt in the positive electrode 1a in the preservation condition. |
