SailNet Community

SailNet Community (
-   Living Aboard (
-   -   Please help me with batteries... (

toastchee 06-27-2006 11:17 AM

Please help me with batteries...
Marine batteries, that is.

I'm trying to understand how to get power on my boat. I'd like to get a marine battery that can power some fans and my running lights. The more amps the better.

I sorta don't understand how I would recharge one at the dock or in my car. Ideally it would charge in the car with some sort of hookup during a long trip. IF I could trickle charge it during the week, that would be cool too. How do RVs do it?

sailortjk1 06-27-2006 11:41 AM

A little more info might be helpful?
It sounds like you have a smaller boat with either no motor or perhaps an outboard motor. If your only runing fans and running lights, I would think a deep cycle group 27 of around 80-90amp. would be plenty. That should give you many hours for your usage. As far as recharging, it doesn't sond like you have an alternator on your motor or an aux. charger wired into your boat. I would simply find myself a charger from the marina, they come with aligator clamps, clamp on, plug it in and charge your battery once a week or so. Your not drawing a whole lot with fans, you should be just fine.

davidbrooke2003 06-27-2006 11:52 AM

Charging batts
I would get a solar panel. Rather than spend money on a charger that is only good at a dock you could buy a solar panel that will give you power anywhere. If you get a small panel you will not need a regulator.

hellosailor 06-27-2006 11:59 AM

Toastchee, you might want to do a little work online looking at marine or RV batteries and charging systems, or pick up a classic little book called "The 12v Doctor" or "The 12v Bible" from many boating stores.

Any battery that is small enough for you to conveniently lift and carry from your boat to your car, won't have a lot of power. "Lot" being a relative thing, maybe it wil be enough for you. And a battery in a car is literally a bomb, if it isn't bolted down and you are in an accident, it becomes a 40-pound missile filled with caustic acid. You car's charging system is also not designed to recharge it, unless you start modifying you'll just ruin it, and your car battery.

So...if you start over, by figuring out how much power you need and for how long, then you can start designing a whole system. Or, just buy a deep cycle/trolling battery at WalMart along with a charger for it, and see if that works for you.

sailingdog 06-27-2006 01:40 PM

I think the solar panel charger is a good one. It should top off your batteries while the boat is just sitting at the dock. If the panel is small enough, then you can just wire it directly to the battery, and won't need a charge controller.

However, you're really much better off sizing the battery according to the loads you're going to put on the battery.

sailandoar 06-27-2006 01:58 PM

Add a battery to your car...
Mount an extra battrery in your car or truck... perhaps in the trunk, and then just take it out and use it when needed. A switch is needed to be sure you don't short out the leads when the extra battery is disconnected.

A '24' series is a nice size to carry and will run lights etc for a weekend camping/sail if your frugal. The '27' series battery is portable but you can get a strain or a hernia pretty quickly with one. Two '24' series deep cycle would be more juice and easier to move around than a '27' series.

Valdare 07-12-2006 05:44 PM

You can buy a deep cycle Optima battery 34 series that are smaller than most 27 series. The AMG Optima can actually be installed upside down side ways and are water proof.

I have seen rv trailers that when plugged into the car via the lighting plugs also has a charger, charging up the extra rv battery.

There are many ways to accomplish your simple needs with out going overboard. The solar charger really works well, we use one on a boat hoist to keep the boat battery charged and the hoist battery charged using a simple cig. lighter adapter.

Good Luck,


toastchee 07-12-2006 10:27 PM

Thanks guys, I now have a marine batt and deep cycle charger. I can build from there. Ideally I'd like to power my CPAP snoring machine overnight on the boat. Any other sailors have one of those?

sailingdog 07-12-2006 11:27 PM

What is a CPAP snoring machine???

infonote 07-13-2006 05:05 AM

You can try a combination of solar and wind energy to charge your batteries

All times are GMT -4. The time now is 08:03 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
(c) LLC 2000-2012

For the best viewing experience please update your browser to Google Chrome