An electronic battery tester for testing a storage battery that includes a battery housing with a plurality of electrochemical cells electrically connected to terminals of the battery is provided. The battery tester includes positive and negative connectors that can connect to the battery terminals. The tester also includes a temperature sensor that can measure a temperature of an individual electrochemical cell of the plurality of electrochemical cells. Processing circuitry, which is coupled to the temperature sensor, is configured to test the battery using the positive and negative connectors and to provide an output related to the temperature measured by the temperature sensor. The present invention also provides a battery charger with an integrated battery cell temperature sensor.