Ebay 12 v panels charge car battery?!?!

[sticky]

Will these charge a car battery through the 12v power plug thing inside the car? http://www.ebay.ca/itm/2PK-2-Watt-12...item27f8b2d335

Does it even work like that? or do i have to direct connect to the batttery... and will these ebay ones work? like and not wreck ****? cause ya know...

[Bala]

Will these charge a car battery No, to small

through the 12v power plug thing inside the car? If you did want to do that you would need the ignition on accessories, that would be silly

http://www.ebay.ca/itm/2PK-2-Watt-12V-Solar-Panel-12-Volt-Battery-Charger-Maintainer-Two-Pack-/171676193589?pt=LH_DefaultDomain_2&hash=item27f8b2d335

Does it even work like that? or do i have to direct connect to the batttery... and will these ebay ones work? like and not wreck ****? cause ya know...

Are you just wanting to maintain a battery or charge it.

[Wy_White_Wolf]

They will not charge dead battery. Only maintain the current charge level.

WWW

[Sunking]

Let me put it to you this way. A 2 watt panel will not even charge a Cell Phone battery. It takes at least a 10 watt panel to charge a Cell Phone, and that could take a couple of days.

[inetdog]

Let me put it to you this way. A 2 watt panel will not even charge a Cell Phone battery. It takes at least a 10 watt panel to charge a Cell Phone, and that could take a couple of days.

I think that you are overstating that a bit.
A high power USB charger will deliver 2A at 5V and can charge a good sized cell phone battery (2000mAh) in a couple of hours.
Even allowing for 50% efficiency loss, a 10W panel should be able to charge a cell phone in one day.

[SunEagle]

Will these charge a car battery through the 12v power plug thing inside the car? http://www.ebay.ca/itm/2PK-2-Watt-12...item27f8b2d335

Does it even work like that? or do i have to direct connect to the batttery... and will these ebay ones work? like and not wreck ****? cause ya know...

Some car manufactures control power to the 12volt power outlet which may be turned off when the ignition key is not switched at least to the "accessories" position.

Other manufacturers allow you to use that 12volt power outlet anytime even without the keys. This can cause the battery to drain if someone leaves their device plugged in overnight. So you need to determine which type of vehicle you have.

Those 2 watt panels will barely keep your battery "maintained" to 12 volts. They will not have enough power to recharge the battery if you drain it.

As for using the 12v outlet or not. IMO it is always better to use the shortest length of wire between the battery "charger" and battery so I usually connect the charger directly to the battery terminals.

[SunEagle]

I think that you are overstating that a bit.
A high power USB charger will deliver 2A at 5V and can charge a good sized cell phone battery (2000mAh) in a couple of hours.
Even allowing for 50% efficiency loss, a 10W panel should be able to charge a cell phone in one day.

Only if you point the panel directly at the sun between 10AM and 2PM.

You can forget about getting enough sunlight if you just leave that 10W panel on the dashboard.

[Sunking]

I think that you are overstating that a bit.
A high power USB charger will deliver 2A at 5V and can charge a good sized cell phone battery (2000mAh) in a couple of hours.
Even allowing for 50% efficiency loss, a 10W panel should be able to charge a cell phone in one day.

No I am not. Those are 2 watt 12 volt battery panels generating a whopping .12 amps. Hook that up to a USB charger and you get .6 watts and it would take several days to charge a cell phone. Use Swich mode to get 2 watts would take up to 2 days maybe more in winter .

Where are you coming up with 10 watts at 5 volts?

2 watts on a 12 volt car battery is useless and at $20/watt is robbery. A new car burns more than 2 watts parked keeping all the Gizmos running. They do make 10 to 20 watt Battery Tenders for parked cars to keep them topped up, but even they cannot charge a car battery. Just generate enough to over come self discharge and the Gizmos running while parked.

[Sunking]

You can forget about getting enough sunlight if you just leave that 10W panel on the dashboard.

Where are you getting 10 watts from?

The OP is referring to 2 watt panels right?

At $20/watt is robbery...

[SunEagle]

Where are you getting 10 watts from?

The OP is referring to 2 watt panels right?

At $20/watt is robbery...

inetdog mentioned the 10 watt panel in his response to your post about charging a cell phone.

IMO those 2 watt panels are only good for using as a door stop.

[Sunking]

IMO those 2 watt panels are only good for using as a door stop.

Yeah they would make a lousy boat anchor. Well if you tried to charge a car battery with them you would have a good boat anchor with a dead battery.

[inetdog]

Where are you coming up with 10 watts at 5 volts?

You are the one who said that it would take a 10W panel a couple of days to charge a cell phone. I was responding to that, not to the OP's 2W panels, which are, as you noted, pretty ridiculous.