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Old 06-13-2010, 09:17 AM   #1
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Default Low voltage

Hey guys, I got a new lipo battery for my box (14.4v 2650 mah) and charged it up at .5 amps the first time. Worked great with plenty of power. I probably started my car 10 times that evening with no issues. The following week I charged the battery again at the same rate but wasn't able to go racing. This week I attempted to charge the battery but got a low voltage warning so I couldn't charge it. I even tried a friends charger and got the same reading.

Any idea what is going on with this brand new battery?
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Old 06-13-2010, 09:38 AM   #2
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May be better to post this in the Radio / Electronics forum
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Old 06-13-2010, 09:46 AM   #3
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Quote:
Originally Posted by petevette View Post
Hey guys, I got a new lipo battery for my box (14.4v 2650 mah) and charged it up at .5 amps the first time. Worked great with plenty of power. I probably started my car 10 times that evening with no issues. The following week I charged the battery again at the same rate but wasn't able to go racing. This week I attempted to charge the battery but got a low voltage warning so I couldn't charge it. I even tried a friends charger and got the same reading.

Any idea what is going on with this brand new battery?
The lowest you should be charging that bettery is 2.6 amps and I bet it can handle 2c charging at 5.2 amps. .5 amps would take all day. What charger are you using? Is it a lipo charger? Lipos will hold their charge for a ling time. 3 weeks and I go to top them off and they are still charged. It could be a bad charger or you overcharged the battery and it's done.
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Old 06-13-2010, 09:55 AM   #4
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Charging at a lower amperage is perfectly fine. See if you can call customer service of the battery manufacturer. They should be able to help.
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Old 06-13-2010, 10:07 AM   #5
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Any of you try one of those low voltage buzzer/meters?
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Old 06-13-2010, 10:17 AM   #6
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This may be an obvious question, but are you using a balance charger each time? If not, you likely have one cell too high / too low. If it's not too far out of whack, it can be corrected, but someone with more experience with that will need to chime in.

....and no, charging it at .5 Amps, won't harm the battery, but it's not necessary. Charge it at 1C, which in your case is 2.6 Amps, and your battery will last a long time, and you'll spend less time charging it.
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Old 06-13-2010, 11:26 AM   #7
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Did you unplug the battery each time you were done
using the starterbox? You should never leave a lipo battery
connected during storage.
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Old 06-13-2010, 11:37 AM   #8
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I have a hard time seeing how a Lipo would discharge from sitting connected in a startbox.
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Old 06-13-2010, 11:46 AM   #9
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Quote:
Originally Posted by Frank L View Post
The lowest you should be charging that bettery is 2.6 amps and I bet it can handle 2c charging at 5.2 amps. .5 amps would take all day. What charger are you using? Is it a lipo charger? Lipos will hold their charge for a ling time. 3 weeks and I go to top them off and they are still charged. It could be a bad charger or you overcharged the battery and it's done.
Yes, I am using a Lipo Charger. I don't think it was overcharged because the two times I charged I got a full indicator.

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Any of you try one of those low voltage buzzer/meters?
Interestingly, I just bought one and connected it to the battery and it didn't buzz nor any of the indicator lights came on. I connected it to another battery and the lights did flash and the buzzer did work in test mode so I know it was working. Just another indicator that the battery in question is in an extreme low voltage state. Doesn't have enough power to activiate the buzzer.

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Originally Posted by Stubbs View Post
This may be an obvious question, but are you using a balance charger each time?
Yes, I am balancing each time I charge.

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Originally Posted by rageworks View Post
Did you unplug the battery each time you were done
using the starterbox? You should never leave a lipo battery
connected during storage.
No, didn't unplug the battery but nor do I unplug my lipo receiver battery. I haven't had any issues with my reciever battery which is on a switch so I didn't think it would be an issue. I have heard that before that you have to unplug the batteries, but what I don't understand is where the draw is coming from if it isn't being used? The box is also on a switch so I really don't see how it could be drawing power from the battery.

Is there anyway to try and charge the battery is the voltage is low? I am sure it is a fail safe of the chargers, but if the battery has gone bad what do I have to lose by forcing a charge if this is possible? It may help recover the battery or make a nice bom fire.
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Old 06-13-2010, 11:56 AM   #10
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Put it on a nihm charge program for 5-10 minutes, supervised and preferably keep it in something fireproof, then try charging it on a lipo program.
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Old 06-13-2010, 11:57 AM   #11
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Quote:
Originally Posted by rageworks View Post
Did you unplug the battery each time you were done
using the starterbox? You should never leave a lipo battery
connected during storage.
Quote:
Originally Posted by neobart View Post
I have a hard time seeing how a Lipo would discharge from sitting connected in a startbox.
there is no need to unplug your battery, nothing is pulling power, there is not a complete circuit in a starter box. ive never n two years unplugged my lipo n my box and ive only had one battery go, it didnt puff or anything just an old battery, tons of cycles.
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Old 06-13-2010, 12:04 PM   #12
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If you can get a voltmeter it will help you find the problem. The balance plug connects to each cell and you can check each cell by using the negative terminal and each of the colored terminals on the balance plug. You probably have a connection that has came loose somewhere.
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Old 06-13-2010, 01:13 PM   #13
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Quote:
Originally Posted by latemodel13 View Post
If you can get a voltmeter it will help you find the problem. The balance plug connects to each cell and you can check each cell by using the negative terminal and each of the colored terminals on the balance plug. You probably have a connection that has came loose somewhere.
Interesting, I will try that. Any other opinions on charging with a nimh charger just to get the voltage high enough so that lipo charger will read it?
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