Originally posted by Cole Trickle
The method I've been thinking about, is to get 2 different resistors. Fx. 1,2 ohm and 2,4 ohm. Then take a fully charged pack and connect it to one of the resistors. Measure amp and volt. Do the same with the other resistor. Now find the delta voltage and delta amps simply by subtraction. Acoording to Ohms law, then divide the delta volt with the delta amps. Wouldn't that result in the internal resistance?
Uhm... if you do at only when is charged, the reading of the I/R should be quite different than the real I/R.
I think that for measuring consistently the I/R of the cell this measuring should be done at the entire time of discharging the element, because for a given load, at some voltage, you get an intensity, but the intensity decreases when the voltage decreases.
But if you want to do some testing, you should get a very big resistor (we should be talking about a 1 Ohm 50w and 1% tolerance) or better.