12v SLA Batteries?

[Gee]

Are these good for anything in the RC world? Starter Boxes or something? Was given to me but don't know anything about sealed lead acid batteries, how to charge them, or even what to use them for.

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[phildogg]

It should work for a starter box.. Back when I was into nitro mine used a lead acid 12v batt.
phil

Starter box batt has more capacity - mine use 7ah batts. One you show is about 1/3 of this. It will work, just might not last as long.

Get a float style charger if you use it as a starter box batt - you keep it hooked up to the batt and it charges it and maintains it at peak charge. Nothing like getting to where you're going to run and realize your box is not charged! Makes for a short day....

[Gee]

Thanks guys. A friend has a float charger I'll borrow and test these out. So the 2.6ah is what the batteries are inside? Kind of like the nihm pack have 3300mah cells. I'm guessing these batteries are more used for backup lighting kind of stuff. I appreciate you guys helping out.

Can I use a 12v car charger to charge them initially?

My MRC 989 will charge lead acid batteries I am just not sure what the settings should be. I e-mailed MRC support asking but they are probably gone for the weekend.

It asks for the following inputs (and my guess)
Battery Type: (Lead acid) may be the only one I get right
# of cells: (I guessed 3 don't know why) max of 5 for lead acid
mah of battery: (2600)
amp: (2.6)
temp cutoff: (120)

What do you think?

[A RC Dude]

hey, u got a good go-cart starter battery now! lol

Yea, the 2.6ah is the same as saying 2600mah, its the batt capacity. 1amp is 1000millamps or ma. If you have a pair, you could wire them in parallel and double the capacity to 5.2ah (5200mah) - would start longer.

I've seen something like these in UPS (un-interruptable power supply) for PCs or workstations where it costs money to lose work if power blinks or goes out. UPS gives you enough power to get your work saved and then shut down if power hasn't come back.

[Patrick]

The cells in lead batteries are about 2.1v or 2v nominal, so 12v batteries have 6 cells. If your charger only does 5 cells then it can't charge that battery.
I don't know exactly what the manufacturer of that battery says, or if there are set charging rules with lead batteries, but don't charge it at 2.6 amps, it's probably a bit much. I think people charge the 7ah batteries at .7 amps or less than 1 amp. So I'd probably charge that battery at around .5amps or no more than 1 amp. I suppose you could e-mail Power Sonic and ask them what the safe charge rate is. http://www.power-sonic.com/index.php?id=29 Your battery doesn't come up when you search the part number.
I'd don't really know what you could use it for though. Maybe a tx pack

[Gee]

Thanks for the help. I will try the float charger out my friend has. Basically a trickle charge. I didn't think about hooking them together. I was given three of them. I will see if they are any good. I've been looking for a starter box for an RC10GT and thought if these work they could be used for it. It's not for me. I've got a neighbor actually two neighbors that have nitro cars. Late x-mas gift when I find a deal on one. Trying to eliminate all the excuses why they never run their RCs. They have lived next door for over six months and I've only seen thier RC running twice. Got a give some crap about it.

Hobbico "overnight" 12v changer that came with my starter box 7ah batt charges at 600ma and they spec 12-16hrs charge time on batt box as a normal charge.

Car trickle charger is usually 2-5amp and a motorcycle trickle charger is usually 1-2amp depending on size. I def would not try more than a 1amp charge rate, the float charger should be fine unless its for a car - they come in diff sizes. I keep a Battery Tender on my motorcycle batt and its 1.25a. The one on my starter box batt ins the Battery Tender JR and its rated for 750ma. The one they sell for cars (battery Tender Plus ) is 5amps.

Check the specs on your friends and make sure its not too much. Three of these in parallel should do a good job as a box batt.

[Gee]

Got a reply from MRC support today here's what they said.

It's only a 2.6AH battery which comes out to 2600 mAh's. Remember that 1 amp hour (AH) is 1,000 mAh's. Set up the 989 under Lead Acid (will also charge Gel Cell), enter in 2 cells (every 6 volts is one cell to the 989 for that type of battery) and then 0.50 amps.

I'll set the superbrain up to charge them and see how they do. Three of these will be a lot to lug around for a starter box. I'll include them with the starter box if they want them. If not I think Patrick wanted one for a RX pack. Better take two to balance the RC out.