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Unread 25-03-2016, 13:36
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AKA: Brian O'Sullivan
FRC #4561 (TerrorBytes)
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Re: Severe voltage drop

Quote:
Originally Posted by Al Skierkiewicz View Post
Ryan,
You misplaced a decimal...
Typical battery is 0.011 ohms internal
We recently did a survey of all of our batteries (testing involved removing them from chargers for half an hour prior, then taking 5 readings between 10 seconds or so of connecting them to an unloaded motor). The batteries that we had purchased brand new all had an internal resistance of 0.016 ohms, our average batteries (owned for a year+) had around 0.018 - 0.019, and our older batteries that we have seen brown outs with were around 0.021-0.024.

Is the 0.011 ohms number an ideal case or should we really expect to purchase batteries with that resistance? Or could our testing method have been bad?