How long do you run your batteries?

Niner, thanks for that tip!!

profdant139 wrote:
It also helps to use a hydrometer -- a very low tech device -- to test the specific gravity of each cell. When one cell starts to show a different reading than the others, this is a time to replace the battery. There is probably a way to revive a bad cell, but I would not want to take a chance on being stranded with a bad battery.

My last set of group 31 12 volts lasted for five years, with careful maintenance, and I used them about 70 or 80 nights per year. A lot of cold-weather boondocking. But I never ran them down below 12.1 volts, I always checked the water, and I always kept them on a battery minder when not in use.

Now that I have a portable solar panel, the batteries rarely get below 12.3 when in use. I think that might help extend their useful life, but I am just guessing.

The one thing that I do not do is an equalizing charge. I have been told by folks who really are experts (hi, Mex and Niner!!) that equalizing is a good idea. But I do not have a charger that will give me that capability, and the cost of really good charger may outweigh the extra battery life that I would gain. It is a matter of dollars and cents.

(Has anyone done that calculation, by the way? How much does a good charger cost, and how much extra life would you get by equalizing? Does it pencil out??)

You have the means to do an equalize charge with your solar panel... just bypass the charge controller and run the 120w panel direct to the battery. All it takes is a screw driver after all the red light stop blinking. About 3 hours aimed in mid day sun should do it. Once every 6 months is good, or right before storage.

Swap the panel wired from the input side of the charge controller to the middle, out put side of the controller, where the output wires are. cinch the screws down, and wait 2 to 3 hours in good mid day sunshine, and you are pretty much done.

Thanks guys. I service them regularly and they've never been a problem. As much as they cost I think I'll try them a couple more years!!

wolfe10 wrote:
Too much of the equation determining effective battery life is based on their "care and feeding" that there really is no standard rule.

True and I'll add, "Batteries are like tires, you take care of them and they'll take care of you."

-Tom, W3TLN

wolfe10 wrote:
Too much of the equation determining effective battery life is based on their "care and feeding"

...and it's measured in cycles, not years of ownership.

My 6v Sams Clubs are 7 years old and are fine.

My Interstates lasted 9 years.. but at six I can make the following recommendation.

Stick some cash in an envelope at the start of the camping season and IF they fail.. you are ready to head to Sams or Costco and grab replacements.

IF they do not fail.. Well camping season ends just in time to do your Christmas Shopping.. Use said cash with great Joy.. Repeat next year.

My Trojan T-105's were purchased in 2008. I have done my best to keep them from dropping below 50% charge, I disconnect them when fully charged and not in use, and they seem to work just as well now as when they were brand new.

In a situation such as this CLARITY of electrolyte in a hydrometer is a key point.

Charge the batteries until they bubble steadily. Continue for 15-minutes more.

Dip the cells. Clear bubbles are of no concern. Smoky tinted liquid is what you do not wish to see. If so much as one cell has smoky or red tint replace both batteries.

My cheap GC batteries are 12 years old and even I don't use them in RV anymore, they still hold some charge.
I remember equalizing them once in their life.
Beside equalizing, you can buy advanced charger that does desulfation.
Those things are known for decades, but for some reason don't gain deserved popularity.