Charging control system for uniformly charging a series connected battery array

摘要

A charging control system for use with a battery charger for charging a battery array which is constituted by battery cells includes charging control units corresponding individually to the battery cells. Each unit includes a voltage-regulator circuit for generating a reference voltage corresponding to the fully charged voltage of the battery cell and a comparator for comparing the inter-electrode voltage of the battery cell with the reference voltage. When the inter-electrode voltage has reached the fully charged voltage, the comparator cooperates with an amplifier to turn ON a field-effect transistor of a bypass circuit of the unit, to thereby divert the charging current from to the battery cell to the bypass circuit. The amplifier receives a feedback voltage indicating the bypass current and operates to keep the bypass current constant, thereby preventing overcharging of the battery cell.