Nickel-metal hydride storage cell having a high capacity and an excellent cycle characteristic and manufacturing method thereof

摘要

A nickel-metal hydride storage cell is composed of a non-sintered positive electrode which is filled with a nickel active material whose particles are coated with cobalt compound layers of divalent or greater and a metal hydride electrode which is filled with a surface-treated hydrogen-absorbing alloy. In the cell, the positive electrode non-reactive capacity rate (represented by the Equation 1) and the negative electrode charge depth (represented by the Equation 2) after the initial charge/discharge are 16% or lower, and 80% or lower, respectively. This construction makes it possible to take larger actual cell capacity by setting the value of the negative electrode charge depth to the degree which causes no rise in the cell internal pressure, thereby expanding the capacity of the cell. $$ $$