| 摘要 |
PURPOSE:To improve the efficiency of use of positive electrode active material by adding twisting into the positive electrode active material. CONSTITUTION:Fibers of 1.0mum to 2.0mm in diameter twisted from a plurality of single threads are added in positive electrode active material. By adding twisted fibers into the positive electrode active material as such, if fine cavities on the surface and the part near it of the positive electrode are choked with sulfate produced by the reaction to the electric discharge, the sulfate may be scattered into clearances between respective single threads forming the twisted fibers by the capillary phenomenon. Since the reaction even inside the positive electrode is effected and there remains less unreacted active material, the effi ciency of use of the positive electrode active material is improve. To scatter sulfate sufficiently, it is required that the diameter of each of cavities should be 0.1mum or more. As a result, it is recommended that single threads of twisted fiber should be 0.01mum to 100mum in diameter and the optimum diameter of twisted fiber be within 1.0mum to 2.0mm. |
