Batteries: How’s Your Charge?

By Phil Blackburn – Reprinted from Fall 2003 Motorcader

This has been a busy summer. We hope you all have had a good summer full of travels. We have had several questions about battery maintenance. Here are some tidbits we hope will answer some of your questions and hopefully prevent problems up the road.

Here are some “general care procedures”:

1. Cycle the battery lightly (20% or less depth of discharge) for the first few cycles. This helps complete the forming process of the plates (in case they are not finished formatting).

2. Never charge a wet battery with a sealed (gel cell) battery charger. The wet battery needs higher voltages to finish the charge and without it, the batteries never come back to 100% and sulfation can occur.

3. Never charge a sealed (gel cell) battery with a wet battery charger. The higher voltages that a wet battery charger generates cause excessive gassing too fast for the sealed battery to recombine, causing dry-out and battery failure.

4. Never store a battery in a discharged state. The sulfate that forms during discharge should not be ignored for an extended time period because severe sulfation will take place sometimes, making the battery impossible to recharge fully.

5. Always keep the tops of the batteries clean. The film on top of the battery can cause the current to migrate between the posts, accelerating self-discharge.

6. A fully charged battery will give you the best and longest service. Be sure the batteries are fully charged before testing or using in your RV’s.

7. Never remove vent caps under any circumstance on gel products. Sealed products should not be opened because the internal pressure necessary for recombination will be released. If the internal pressure is released, the battery gas will not recombine, causing the water in the gel to be reduced, lowering the battery’s capacity.

8. Gel batteries can be installed and operated at any angle although they should not be charged or discharged upside down. There is a small residue of acid that may be released out of the pressure relief valves during charging if placed upside down.

9. An overly discharged battery may need to be cycled a few times before it can recover fully. If a battery begins to heat before coming up to a full state of charge, it may be necessary to discharge the battery and recharge it a few times. This charge and discharge cycle may help the current acceptance of the battery and facilitate its recovery to a usable condition.

Periodic cleaning of batteries can be done with a water and baking soda solution, followed by a thor­ough rinsing with clear water.

Here’s hoping everyone is fully charged and ready for a little cooler weather. We still have a few motorcades and events yet this year before the weather really gets cold.

  • Never add water to a gel battery.
  • Before washing batteries, make sure no safety vents
  • have stuck open to prevent baking soda solution from contaminating electrolytes. Rinse with clear water.
  • It is essential when replacing the cables on the bat­tery that the positive cable is attached to the positive post and the negative cable is attached to the neg­ative post. Battery posts are marked (+) positive and (-) negative and identified on the battery case. Also, if a “fast charger” is used while the battery is in the motorhome, disconnect both battery cables before connecting the charger.
  • Battery fluid is a corrosive acid solution; do not allow battery fluid to contact eyes, skin or clothing. Don’t lean over the battery when attaching clamps or allow the clamps to touch each other. If acid splashes in the eyes or on the skin, flush the contaminated area immediately with large quantities of water.
  • A battery generates hydrogen gas which is flamma­ble and explosive. Keep flame or spark away from the filler holes. Do not use a booster battery or any other source with an output that exceeds 12 volts.
  • Battery posts, terminals, and related accessories contain lead and lead compounds.