Vehicle Battery Solar Charger

[peteco]

I got a 1.5w solar charger from Northern to keep my vehicles' starting battery charged when the vehicle sits. It puts out 22.3 volts when not connected to the battery. Will this voltage harm the battery?

[papab]

Probably not since it's only 1.5W. Once you connect it to the battery the voltage will drop quite a bit. I wouldn't trust it without knowing more though. Is it just a solar panel and it gets directly connected or is there some charge controller included?

[peteco]

Originally Posted by papab

Probably not since it's only 1.5W. Once you connect it to the battery the voltage will drop quite a bit. I wouldn't trust it without knowing more though. Is it just a solar panel and it gets directly connected or is there some charge controller included?

Packaging says it has overcharge/discharge protection. It looks like the Northern house brand (Ironton) of the Coleman 58215 on their site. Reviews are pretty good. Years ago I had one that killed a battery so yeah I am a bit wary. I am testing it on an extra battery before putting in my Roadtrek. It brought the battery up to 12.57 volts from 12.43 over the course of 5 hours.

[Bruceper]

Without a charge controller, you risk over charging and killing the battery.

[peteco]

I left the solar charger hooked up last night. The voltage dropped to 12.47. So there is some "leakage" through the diode. I will keep testing it on my spare battery for a few days. It will be interesting to see how high the voltage goes. I should be able to catch it.

Any thoughts on what would be the max voltage before the battery is overcharged and could be damaged?

[avanti]

I tried several of these cheap battery-maintenance chargers (from Harbor Freight) on several vehicles. I was never able to convince myself that they produced a net gain in charge.

[peteco]

Originally Posted by avanti

I tried several of these cheap battery-maintenance chargers (from Harbor Freight) on several vehicles. I was never able to convince myself that they produced a net gain in charge.

That may be the case here, but most reviews are positive. I paid $8 for it as it was a closeout. Northern is closing out their Ironton line and replacing with Klutch named items. I wonder where they come up with these goofy names.