The Batteries On My RV Are Only Charging Up To 74%, Why?

by Don
(Slidell, La.)

When I set up the charger on my 2 - 6 volt batteries it won't charge more than 74%. At what point do I consider changing the batteries. Everything still works fine but I want to be sure.

ANSWER: Greetings Don thanks for submitting your question on our Ask An RV Question Page.

The best way to find out if the batteries are in good shape is to have them tested. Before you do that there are a couple of things you should do to eliminate any other potential problems.

1. Double check the electrolytes in your batteries. Top them off with distilled water as needed. Low electrolytes in a battery can affect how well they take a charge. The batteries could also be sulfated, which will prevent them from charging properly.

2. Check to make sure that all connections to the batteries are tight and clean.

3. The problem may be with the battery charger you are using. If it is a two stage charger the second stage may not be operating. A Two stage charger is designed to charge your batteries up to about 75% to 80% and then go into trickle charge mode (also known as float charging). If the charger is malfunctioning it may not be doing the trickle charge stage

It sounds like you are using a stand-alone charger to charge your batteries. Let me take a moment to recommend a charger that will probably do a better job of safely charging your batteries then the one you have now. It is called the BatteryMinder Battery Charger / Maintainer with Desulphator.

I recently had the opportunity to test the BatteryMinder. Even though my motorhome has a two stage battery charger, I used the BatteryMinder to maintain my motorhome's batteries for a couple of months and it did an excellent job.

The BatteryMinder is a 3 stage charger with a built in desulfator that automatically dissolves sulphation on the battery plates. It can charge and maintain from 1 to 5 batteries at a time (12 Volt batteries parallel-connected or 6 Volt batteries series-connected). It has polarity reverse protection and it will not overcharge your system.

Hopefully the above information will get you to the bottom of your RV's battery problems.

Do you have any suggestions or comments on this topic? You can add them to this page by clicking on the "Click Here To Post Comments" link located near the bottom of this page.

Happy RVing

RVing Al

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