Join Date: Aug 2006
Location: Arlington, VA
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I've found in the process of the battery tests we've been doing over the past year that the jumper size can make a very big difference, much more than is intuitive. This is particularly true when it comes to charging the batteries, since jumper size affects the internal resistance of the battery as seen by the charger.
Accordingly, I'd say use a jumper much larger than you'd imagine necessary; I've replaced all mine with 1/O and 2/O very short jumpers. If you align the golf-cart batteries (I assume that's what you're talking about) correctly, you can make these jumpers less than a foot long overall.