12v off grid battery charging

halfmoa

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Joined
Aug 19, 2011
Messages
955
I've got a cabin located in an area with no electrical service. I'm installing a 12v led lighting system but have a question that I hope you guys can help me with.

First, my system will be a total of 15 watts maximum draw at 12 volts. The battery is a 12v marine deep cycle rated a 109 amp hours meaning the battery should last for somewhere around 75 hours of constant use which will NEVER happen. The lights may be used a 4 hours once every week....and that's an absolute max. Out of camping season it'd probably be closer to 2 hours every month. The cabin is accessible by vehicle occasionally, often you have to park and walk.

Now the question. How do I keep this battery charged? An I crazy to think that, on the good weather visits when I am able to drive to the cabin, I could hook the battery in parallel to my vehicle with jumper cables to keep it topped off? I've read some really nasty things about solar maintainers not having overcharge protection and killing batteries like it's their job.

Thanks everyone!
 

Bondo

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Apr 17, 2002
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Re: 12v off grid battery charging

I could hook the battery in parallel to my vehicle with jumper cables to keep it topped off?

Ayuh,.... I donno 'bout Topped off, but, Ya jumpin' the storage battery will charge it so long as yer motor's runnin',....
 

Barnacle_Bill

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Feb 8, 2004
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6,469
Re: 12v off grid battery charging

Solar charger with a controller. This will prevent over charging according to what I read about them.
 

Boomyal

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Aug 16, 2003
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12,072
Re: 12v off grid battery charging

Get a solid state regulator for your solar panel. The first time I used a solar charger on my houseboat, I returned in the spring to find the battery boiled dry. I bought a regulator for it and never had any problems. The regulator limited the charge and kept the panel from bleeding off juice during the night/dark.
 

blackhawk180

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Jun 14, 2012
Messages
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Re: 12v off grid battery charging

Get a solid state regulator for your solar panel. The first time I used a solar charger on my houseboat, I returned in the spring to find the battery boiled dry. I bought a regulator for it and never had any problems. The regulator limited the charge and kept the panel from bleeding off juice during the night/dark.

Absolutely the way I would go. Before I ran AC to my boathouse, I used a solar panel with regulator and never had a problem. At the price of gas (assuming the jumper cable system), it will pay for itself eventually and you'll arrive at your cabin knowing you have a full charge. Also better for the battery to have a regular current applied to it.
 

MTboatguy

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Jul 8, 2010
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8,988
Re: 12v off grid battery charging

I use a little 15 watt solar suitcase system that I bought at Harbor Freight for about $70 bucks, it has a regulator built in and seems to maintain my deep cycle RV batteries with no problems at all.
 

halfmoa

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Aug 19, 2011
Messages
955
Re: 12v off grid battery charging

Alright! Several things for me to think about here. Thanks y'all!
 
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