Author Options:

can i charge this battery with a solar charge controller? Answered

I have recently bought this solar charger kit from amazon.com (http://www.amazon.com/gp/product/B004FOEUI0/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1) and was curious if i could charge two of these small sla batteries hooked in a parallel to power a project. If it is too much power how would i bring it down to a safe level for the batteries? help would be appreciated thanks:


If you wire the batteries in Series then yes the panel will trickle charge them fine. If you wire the batteries in parallel than the panel will be too much for them and may damage the batteries.

OK i am sorry i must have series and parallel mixed up. so series is positive to negative?
What would you say would be too much current to charge these batteries because i have seen chargers that say 7 amps on them and i am assuming that is too much current could you please correct me if i am wrong?

Yes series is positive to negative. The solar panel is only giving you about 400mA at best. The charge controller bundled with the panel is able to handle up to 3A but since the panel is only providing a max of 400mA the battery won't get more than 400mA being fed into it. So if you get a charge controller rated for 7A then you can feed up to 7A worth of power into them. But those controllers are meant to charge multiple 12V batteries in parallel. That way the 7A is being divided between multiple batteries and won't charge the batteries too fast. If you charge them too fast they overheat and can explode.

I don't want to start another question and i feel it would be appropriate to ask since we are on the subject. i was wondering if it would do any damage to the solar panel if i hooked another smaller 12 volt solar panel in series with the one that i bought and if i would get any extra power out of it to charge the batteries faster?

You will want to connect the extra panel in parallel. Red on red and black on black. If you want faster charging you need more current. Wiring things in parallel gives you more current. Wiring things in series gives you more voltage. If the panels don't have built in protection diodes you will want to wire a couple in so the power from the panels goes into the battery/charge controller and not back into the panels. You can wire the diodes in on the end of the positive wire before it goes into the charge controller.

Ok thanks you have been a big help. One last qeustion is it ok to hook two slas with the same voltage but a different ah together in a series?

Yes. Just be sure you have the blocking diodes in place so the power from the stronger panel doesn't get to the smaller panel and damage it.

The charger is fine. Pretty well perfect for trickle charging your batteries.