| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that an effort for increasing the porosity of an active material to improve the utilization factor of the active material of a positive electrode plate leads to a decline in the bonding strength between particles composing the active material, negatively effects to weaken the active material as a structure to cause the active material's dropping from the positive electrode plate, a decline in adhesion between the active material and a lattice, in current collection efficiency, and in conductivity between active materials, etc., when extensive charge/discharge is repeated, thus reducing the life of a battery; and to provide a lead battery having a positive active material containing a tungsten carbide an additive to improve the positive electrode utilization factor, and to maintain a high discharge characteristic and a capacity characteristic even when charge/discharge is repeated. <P>SOLUTION: A closed lead battery having a positive electrode plate containing a tungsten carbide as an additive is provided. In the battery, the tungsten carbide of 0.01 to 15.0 mass% is added to lead powder. <P>COPYRIGHT: (C)2008,JPO&INPIT |
