#### darwin

##### Well-Known Member
I have a 2 watt solar panel from HF, about 5yo. It's supposed to be automatic in it's charging to cut off at 12.6v. If a m/c battery is about 10% depleted how long will it take to charge the battery to 100% if the m/c batt is 12v 6ah? I'm just wondering how much the batt can be charged in say a 10hr day of sunlight. I know just enough about electric math to get frustrated. Chinese instructions are clueless and no help whatsoever.

You'll never ever see full charge at 12.6 volts bro. Im guessing it's an AGM battery. I really really hope it's a typo and you meant 200 watt panel lol. 2 watts might never get full charged before the battery loses capacity just from being old lol.

Actually it's 1.5 watts. Bought this to keep a scooter/m/c battery topped off when parked so it didn't get too low. That's what it's advertised as. Anyways Need someone good at electric math to see if it will work.

1.5 Watt Solar Battery Charger (harborfreight.com)

I read the reviews of that HF solar battery charger. People say it works. Surprised me, one dude say's it put's out 18v as advertised.

1.5 watt = 1,500MA (milliamps) That's a good trickle charger but I doubt a solar charger can put that out 100% of the time.

1.5W Solar Trickle charge, I bet it would take 3 - 5 days to top off a 12v 6 amp battery to 100%.
If the battery was almost dead it would take forever to charge it up.

I use a small Battery Tender 12v 750MA trickle charger to top off 12v 10A car batteries and that always takes 3 days to charge it 100%

When charging a almost totally dead 12v 10A car battery (Wet, AGM, Gel) I use a 15A 10A 2A Smart battery charger. It will charge a totally dead car battery in about 6 -8 hrs. But to top off a good battery it only takes about 10 mins.

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I read the reviews of that HF solar battery charger. People say it works. Surprised me, one dude say's it put's out 18v as advertised.

1.5 watt = 1,500MA (milliamps) That's a good trickle charger but I doubt a solar charger can put that out 100% of the time.

1.5W Solar Trickle charge, I bet it would take 3 - 5 days to top off a 12v 6 amp battery to 100%.
If the battery was almost dead it would take forever to charge it up.

I use a small Battery Tender 12v 750MA trickle charger to top off 12v 10A car batteries and that always takes 3 days to charge it 100%

When charging a almost totally dead 12v 10A car battery (Wet, AGM, Gel) I use a 15A 10A 2A Smart battery charger. It will charge a totally dead car battery in about 6 -8 hrs. But to top off a good battery it only takes about 10 mins.
You driving a powerwheels bro? Where did you find a 10 amp hour car battery? That would provide like 90 cranking amps lol. Most car batteries are 70 amp hours. The batteries in my cadillacs are 90 and 100 amp hours. You won't get 1000 cold cranking amps from a 10 amp hour lead battery.

You driving a powerwheels bro? Where did you find a 10 amp hour car battery? That would provide like 90 cranking amps lol. Most car batteries are 70 amp hours. The batteries in my cadillacs are 90 and 100 amp hours. You won't get 1000 cold cranking amps from a 10 amp hour lead battery.

Never said Amp Hours
Yes I know car batteries are 55ah to 100 ah
I said a car battery is 10 amps because a 10 amp charger is used to charge one

1.5 watts is not = to 1.5 amps. It takes 18 watts to provide 1.5 amps at 12 volts.

I have a HF solar charger. The fellow I got it from used it to keep his trolling motor battery charged.

Actually it's 1.5 watts. Bought this to keep a scooter/m/c battery topped off when parked so it didn't get too low. That's what it's advertised as. Anyways Need someone good at electric math to see if it will work.

1.5 Watt Solar Battery Charger (harborfreight.com)
If you read the description it says it's meant to over come small drains such as the clock or vehicle alarm systems. Probably be nice if you store a vehicle outside for long periods without driving it.

1.5 watts is not = to 1.5 amps. It takes 18 watts to provide 1.5 amps at 12 volts.
Boy, I sure blew that one Thanks for the correction
Somehow I got mixed up when using the watts to amps calculator
1.5w @ 12v = 125 milliamps or .125 amps
That Solar charger ain't as good as I thought.

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