Unused batteries discharging; is solar trickle the answer?

[dave14117]

Have two fifth wheels and since using them we've almost always been on shore power or generator, I think I've been delusional thinking the batteries in the rigs are working. They're unused for months at a time and I've noticed that when we are dry camping, the batteries are no-go. Thought it was just the WFCO converters, but maybe not -- can even deep cycle batteries survive so much time off power? Currently trying to get 3 year old Costco batteries working; they won't keep a charge even out of the RV after being on a car charger.

Question is whether a solar trickle charger is an answer. (No power where we store these rigs.)

Thanks

[Sam_Spade]

MEXICOWANDERER wrote:

Does a reasonably priced controller exist that not only maintains batteries at the correct voltage but weekly or bi-weekly give a surge of voltage for perhaps a half hour?

IF.....it really does "maintain them at the correct (float) voltage", what exactly makes you think that the other part is in any way necessary or beneficial ? Except maybe for trying to eek out a few extra months from batteries that are mostly worn out already.

[red31]

many epsolar charge controllers can be programmed.
voltage set points 9-17v, top charge limited to every 30 days (0-180 mins).
One needs a cable and computer with downloaded software to program.
a 10A version of the landstar ls1024B can be had for <$20 from aliexpress or <$30 on amazon.

https://www.amazon.com/EPsolar-LandStar-LS1024B-Battery-Controller/dp/B00N4QJETA

[MEXICOWANDERER]

Intermediate Question

Does a reasonably priced controller exist that not only maintains batteries at the correct voltage but weekly or bi-weekly give a surge of voltage for perhaps a half hour?

[time2roll]

Yes solar works great. Forget the tiny trickle panels. For the effort get 100 to 200 watts and a good controller.

[Lwiddis]

My TT batteries are maintained with a small solar panel and controller from WindyNation when at rest and covered. This system is completely separate and hooked directly to my two T125 batteries. Works great!

[Housted]

We have a permanent site 5er in the mountains. A 50 watt solar panel works well to keep the two 12 volt batteries trickle charged. I have a battery disconnect so that there is nothing connected but the solar when we are not there. Has maintained the batts for over 2 years with little loss of water and they are fully charged when we arrive. I did tilt the panel for optimum exposure to the sun.

Housted

[fitznj]

I keep my TT at the back of my property and have 2 x 100W panels which keep the batteries fully charger when stored. I take the panels with me if I'm dry camping.

I also have a battery disconnect switch - batteries consistently stay at 12.9.

[Sam_Spade]

All 3 of the previous answers are correct in their own right.
You just need to pick the one that best suits you.

And it looks like your present batteries are toast.

At a minimum you need new batteries and a multi-meter to test them and your converter.

P.S. If the battery disconnect switch is left in the OFF position, your 12 V stuff will work on shore power or gen but the batteries will never charge.

[BFL13]

You other choice it to take the batts home and keep them on a maintainer there. Solar is better, since you can also use it while camping if you get more solar than needed just for storage.

[2oldman]

Disconnecting your batteries works pretty well.

[MEXICOWANDERER]

A decent solar battery float system not only will maintain float voltage but will goose the batteries occasionally with higher voltage to stir the electrolyte. Sizing at 3% per total amp hour capacity is plenty. Cheap and solar management are two incompatible words -- but it's worth every penny.