Abstract: In the rapid charging of a Nickel Cadmium (NiCad) battery, the rapid charging is terminated and trickle charging is initiated when any of three conditions is satisfied: a first condition determined by comparing a sensed instantaneous battery voltage with a target voltage; a second condition which is determined by comparing the instantaneous battery temperature with minimum and maximum values; and a third condition determined by comparing an elapsed time of rapid charging with a maximum value. Because battery voltage versus rapid charging time is a function of ambient temperature, the target voltage is determined from an initial measurement of battery temperature, which is assumed to equal the ambient temperature. The target voltage, which is approximately a linearly declining function of ambient temperature, is determined by reading a stored lookup table using the sensed temperature as an index or address.