Abstract: Electronic circuitry for charging batteries is designed to charge the cells at a relatively high charging rate through a charging path which includes a semiconductor switching means, e.g. a transistor. Control circuitry is provided including a shunting controlled rectifier which is triggered into conduction when the battery has reached its nearly fully charged condition, thus shunting current away from the battery and preferably latching the transistor into non-conduction. A lower rate, trickle maintenance charge is provided by way of a resistor shunt across the switching means. The effect of temperature on the shunt controlled rectifier gating requirements is used in a positive manner to automatically latch the transistor into non-conduction as the cell approaches its fully charged condition while simultaneously preventing overcharging by tapering the battery voltage to a suitable level.