12v car battery and charger question

[ForumSn0w]

I was wondering if anyone here has used a 12v car battery by itself (not hooked up to vehicle) for use of a lipo charger to charge a few batteries? I was thinking about picking one up for the Axial WCC competition to charge up the rigs without using the one in my car the whole time.

How many charges could you get out of the car battery?
Would the voltage drop quickly on the car battery?
Not worth it?
Thanks for any info.

[chrisjlittle]

Originally Posted by ForumSn0w

I was wondering if anyone here has used a 12v car battery by itself (not hooked up to vehicle) for use of a lipo charger to charge a few batteries? I was thinking about picking one up for the Axial WCC competition to charge up the rigs without using the one in my car the whole time.

How many charges could you get out of the car battery?
Would the voltage drop quickly on the car battery?
Not worth it?
Thanks for any info.

You can get quite a few charges out of a car battery. Just figure 12.6 volts is fully charged, 10.5 volts is fully discharged, and lead acid batteries don't like being fully discharged so don't let it get that low. It almost certainly won't blow up if you fully discharge it, but it might not ever take a charge again. Your chargers will probably stop working by that low of a voltage anyways.

If you're serious about keeping a car battery around for charging R/C batteries in the field, get a deep cycle marine battery. They're better for repeated deep discharge than automotive starting batteries and will last longer in that role.

EDIT: I really have no idea how many amp hours are in a starting battery, but most marine batteries are 150Ah+. I also don't know how much amperage a charger draws, but I'd be willing to bet you could charge at least 25 1500 Mah batteries with a 150Ah battery.

[ForumSn0w]

I will look into the deep cycle like you said, although I don't want to waste a $75-100 battery either. Thanks

[chrisjlittle]

Originally Posted by ForumSn0w

I will look into the deep cycle like you said, although I don't want to waste a $75-100 battery either. Thanks

You could pick up a battery from a junk yard, or maybe pick up a used one from a mechanic or a parts store. As long as it will take a charge it'll do fine for a power supply. You won't draw 10 amps with your charger, a pretty badly sulphated battery will provide that for a few hours no problem. You should only buy a new one if you are gonna do this all the time.

[Rockcrawler]

Originally Posted by ForumSn0w

I will look into the deep cycle like you said, although I don't want to waste a $75-100 battery either. Thanks

There not much more than a standard battery. You can get them from walmart for around $50.

I have a little setup in the bed of my truck using a deep cycle marine battery. As far as charges, I have never used it down to where it would not charge anymore.

What batteries will you be charging? Most chargers have to have 12v to run so you probably wont pull it down much further than that if I am thinking right.

I usually throw a little charge on mine every other comp. Sometimes I have 3 or 4 batteries being charged off of it 4 times a comp........

[ForumSn0w]

For a charger: Hyperion EOS0606i ac/dc
Batteries: Thunder Power Extreme 2s 2000mAH lipos

Thinking about picking up a couple more batteries for an Slash that I want to purchase. Maybe.

[Rockcrawler]

Originally Posted by ForumSn0w

For a charger: Hyperion EOS0606i ac/dc
Batteries: Thunder Power Extreme 2s 2000mAH lipos

Thinking about picking up a couple more batteries for an Slash that I want to purchase. Maybe.

Same charger I use. I also run 2000mah packs but there 3 cell. You should not have a problem with draining it too much in a day.


Here is the charger I got..........

http://www.batteryservice.com/produc...mber=SSC-1500A

Paid 49.94 for the charger and 52.94 for the battery (24MS)....just checked the walmart receipt. The battery box was $7.


Edit: The charger will charge at 2, 10 and 15 Amps, Standard, AGM and Gel Cells. Will show voltage and % of battery.

[ForumSn0w]

Awesome, thanks for the posts back! I'll have to check that out. I like the bed mounted battery and external 12v in the bed, pretty slick.

[JavelinSST390]

well, I know I've charged continuously all day off my car battery before without starting it, and after 8+ hours of charging packs (I hit 9 charges one day) I was still able to start my car with no problems.

[Rockcrawler]

Originally Posted by ForumSn0w

Awesome, thanks for the posts back! I'll have to check that out. I like the bed mounted battery and external 12v in the bed, pretty slick.

I need some updated pics.

I also have a Pos and negative wire ran from the battery to the back of the truck. I have those and a ground wire (bolt to the bed) wired into a 3 prong ac connector like this one..........



Then the male side of it is connected to my 1500 watt power supply for AC (soldering iron, dremel, ect).