A rechargeable electrochemical cell charging system is provided having a thermistor that engages the negative cell terminal at a location remote from the negative charge contact. The thermistor outputs temperature data to a controller in the charger that determines the rate of cell temperature increase. When the increase reaches a predetermined predetermined rate, the charge to the cell is discontinued. The cell can also include an air moving system that circulates cool ambient air through battery compartment to cool the batteries being charged.