Battery Tester

[dryan]

I have a voltmeter (multimeter); how can I use this to test AA and AAA batteries?

If I am correct, simply touching the leads of the voltmeter to the contacts of the battery would almost always give me a reading of 1.5 volts.

I think by adding a resistor, I can get a correct reading. How do I calculate what value resistor I need?

[Lance]

You would probably get a better reading using the amp meter. As long as you do it for brief periods you shouldn’t need a resistor for AA and AAA batteries.

[swansont]

I have a voltmeter (multimeter); how can I use this to test AA and AAA batteries?

If I am correct' date=' simply touching the leads of the voltmeter to the contacts of the battery would almost always give me a reading of 1.5 volts.

I think by adding a resistor, I can get a correct reading. How do I calculate what value resistor I need?[/quote']

 

Doesn't really matter much. Once the battery is under load, the voltage drop across the resistor is the output of the battery (assuming it's just the resistor in series with the battery). If the R is really large the reading might not be as accurate.