Two Batteries Are Hotter and Need More Refills Than the Other Batteries in the Bank - What Causes This?

Question:

A couple of years ago I completely updated my electrical system on my Cat 36, Pacific Psalm. I have six golf cart-6v-US-2200 232ah (T105) batteries. One bank of four were installed September 2010 and another of two in January 2012. They are all hooked up to one bank. The four together seem fine, but the two newest batteries closest to the Freedom, Marine 20 Heart Interface, Inverter/charger are heating up and losing water. Is it possible that these were wired together incorrectly? I have noticed last year that the two batteries seemed to get hotter.

Answer:

Sounds like the new batteries are working the hardest of the pack. Not surprising, since they are the newest and hence offer the higher available voltage, and the fact they are connected to the inverter/charger. If you are concerned about how they are wired, please send a photo or diagram and I’ll provide feedback.