Solar Charging A 12-Volt Deep-Cycle Battery

[JohnnyGalaga]

You know how when you leave a battery sit for a while, it slowly loses its charge, so that when you need it, it's dead? Well I hate that. I basically want to use a solar charger to keep a deep-cycle battery topped off.

Where can I find a solar charger that will:

1. Automatically maintain the correct charging voltage under varying brightnesses of sunlight?

2. Detect the battery voltage so it knows not to overcharge it?

3. Allow me to use the battery while leaving the solar charger still hooked up to it?

4. Prevent discharging into the solar cells.

5. Know when to automatically stop charging if the voltage from the solar cells gets too low?

Does anyone know of any reputable dealers that sells anything like this?

If I use a sealed, maintenance-free battery, is it safe to leave it hooked up to the charger indoors indefinitely?

So many questions..........so little knowledge.

Thanks.

 

[rwolff]

Sounds like you need a charge controller. As for the maintenance-free battery, it's always a good idea to keep your battery in a battery box vented to the outside. Maintenance-free batteries aren't truly sealed (except for the absorbed glass mat ones - you can iidentify them because they look like a "6-pack" rather than a "brick" like a flooded cell battery).

 

[Josey]

Get a three-stage charge controller. Bulk for charging fast when the battery is low, absorption for when the battery is nearing full charge and cannot take as many amps and float, a topping charge when it is full. Most of the good ones also have MPPT, a kind of contol that matches voltage and amps to get the best charge from the solar panel.

Any solar dealer will be able to help you. You could try Backwoods Solar in Idaho, but lots of dealers can help. Check out the ads in Home Power Magazine for dealers, brands and reviews. The current issue is free over the web.

Josey

 

[snakebite]

http://www.wind-sun.com/smf/index.php
the forum sponsor is a great place to get what you need.