| 摘要 |
<p>PROBLEM TO BE SOLVED: To keep high discharge capacity and high operating voltage, even at high- current discharge, and to prevent running down earlier with the capacity remaining, by limiting the three-dimensional nickel porous body density and the number of vacancies within a unit distance in an electrode formed by filling an active material into a base of the three-dimensional nickel porous body, within the specific ranges. SOLUTION: This battery with a positive electrode plate having a three-dimensional nickel porous body density of 1.25 g/cc or more maintains the battery voltage of more 1 V, even at the discharge depth of 80%. Consequently, the porous body density is set to more than 1.25 g/cc, in order to secure the capacity of more 80% of nominal capacity of high-current discharge. As the density rises, the voltage rises also, and when rising beyond a certain point, the battery weight is enlarged for maintaining the discharge capacity, and the battery output energy density is lowered. Also, filling of an active material becomes difficult, and from the order beyond the density of 1.8 g/cc, cracks and exfoliation, etc., occur in the electrode plate. Consequently, the density is set at 1.75 g/cc. Furthermore, the number of vacancies within unit distance indicating fineness of grain of the vacancies is set at 45-55 pieces/inch, to prevent cracks, exfoliation, and lowering of the capacity.</p> |
