Solar charge between trips.

[Vladivar]

So I have read the threads I can find on solar and am still unsure what route to take. The situation is needing to keep my single 12v deep cycle topped up between trips (combating the parasitic draw that happens). I have no need for a solar system to power anything, so a 100w or greater system is total overkill for me.

I am thinking I need something in the 10w to 20w range that would be hooked directly to my batt, but I’m not sure if anything that size would have a charge controller - or if indeed a controller would even be needed.

I have looked at units in my local automotive store that are priced in the $30 to $50 range - would this do what I need so that I can hook it up and just pull my batt disconnect switch as normal?

Thx for any advice.

[Splitshaft]

If a panel is connected directly to the battery, the battery disconnect should be turned off. I would likely anticipate any solar panel to deliver half its rated output or less, unless always positioned towards the sun. Small solar panels do not require a charge controller to keep from over charging batteries. In fact, an occasion boost charge is good for lead-acid batteries. Why not just remove the battery and take it or leave it home where it could be connected to a battery tender? I don’t keep my clothes in the camper or food in the refrigerator off season. A battery is just another thing I would leave at home when unpacking.

[SailorSam20500]

I have one that looks like this one. Hook it up when the trailer will be parked for more than a couple of weeks. Seems to have kept the battery fully charged. I hang it on my propane tank cover pointing west. Also used it over last winter - did fine.

https://www.walmart.com/ip/Coleman-2...ainer/15063010

[DavidBo]

I picked up one of these:

https://www.northerntool.com/shop/to...0268_200660268

Here is my high-tech custom installation:



I hook the alligator clamps directly to the battery and the charger pops perfectly in place between the tongue jack and propane tank cover. I've have left this set up for months untouched and the battery remained fully charged at all times. There was also almost no water loss so I doubt there are any overcharging issues. I remove it before towing, takes a whole minute.
Now if I can only figure out how that can of Corona got in the picture!

[Vladivar]

Originally Posted by Splitshaft

If a panel is connected directly to the battery, the battery disconnect should be turned off. I would likely anticipate any solar panel to deliver half its rated output or less, unless always positioned towards the sun. Small solar panels do not require a charge controller to keep from over charging batteries. In fact, an occasion boost charge is good for lead-acid batteries. Why not just remove the battery and take it or leave it home where it could be connected to a battery tender? I don’t keep my clothes in the camper or food in the refrigerator off season. A battery is just another thing I would leave at home when unpacking.

We will be removing the battery as you suggest when we winterize, I’m looking for something to keep hooked up between trips (2 to 3 weeks at a time).

[babock]

Originally Posted by Vladivar

We will be removing the battery as you suggest when we winterize, I’m looking for something to keep hooked up between trips (2 to 3 weeks at a time).

You have a battery disconnect right? As long as you do that, the battery won't discharge enough in 2 to 3 weeks to worry about it.

[SailorSam20500]

Originally Posted by Vladivar

We will be removing the battery as you suggest when we winterize, I’m looking for something to keep hooked up between trips (2 to 3 weeks at a time).

There is really zero value to removing the battery over winter unless you have temps well below -50 F. A fully charged battery will not freeze until about -90 F. Also, the colder it is, the slower the battery will self discharge. So unless you are worried about theft from a storage lot...

I used my Coleman last winter and had a fully charged battery in March, but I'm only in "mild" Michigan. 2 volt solar panel was pointed up-ish and to the SW and got more than enough sun. Panel was hanging on my propane tank cover and angled so snow would either melt or blow off by itself. 5ver next to me had a more custom setup, but was just as happy.

[wnelsonfl]

Picked one up yesterday. I needs controller

$79

[wnelsonfl]

Picked one up yesterday. It needs controller

$79