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Old 08-28-2008, 09:11 PM   #1
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Default 7.4 lipo showing 2 volts

What can I do to get a 7.4 losi lipo to charge. It is showing only 2.3 volts total.
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Old 08-28-2008, 09:12 PM   #2
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thats no good.......how did it get that low? did u buy it used? did u run it on a esc that didnt have lipo cut off?
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Old 08-28-2008, 09:15 PM   #3
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I guess the car was left on over night with batt plugged up. The esc is a mamba micro pro. I dont know what cutoff comes factory.
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Old 08-28-2008, 09:17 PM   #4
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The cut off won't work if the ESC isn't turned off.

You can't leave it plugged in over night, your battery is dead.

There's ways of trying to revive it slowly on low amps on your charger's NiMh mode, but its not exactly the safest thing to do.
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Old 08-28-2008, 09:18 PM   #5
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Quote:
Originally Posted by freeman View Post
I guess the car was left on over night with batt plugged up. The esc is a mamba micro pro. I dont know what cutoff comes factory.
There is no cut out set from the factory. Clip the leads and chuck it. The pack is dead.
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Old 08-28-2008, 09:20 PM   #6
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Packs dumped like that can usually still be charged and still have some life left in them, but do so at your own risk and expect it to puff and die eventually.
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Old 08-28-2008, 09:21 PM   #7
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Thanks for the fast response guys, Ill just write it as a loss.
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Old 08-28-2008, 09:23 PM   #8
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Pop it in a bucket of salt water to kill it (whats left rather) before discarding, I believe thats the proper way to dispose of LiPos.
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Old 08-28-2008, 09:25 PM   #9
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is it bad to leave a lipo plugged in overnight in a car, but the car is off
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Old 08-28-2008, 09:35 PM   #10
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Yes, thats exactly what happened here.
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Old 08-28-2008, 10:02 PM   #11
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Depends on the esc... some will draw a small current and slowly drain the battery, but some don't.

Lipo disposal:
Rather than messing with a salt bath, simply discharge it slowly to 0 volts. That's the idea of the salt bath... saltwater conducts some electricity and will slowly dump the battery. But it's not necessary. Once the voltage is 0, there is no energy in the pack to do anything destructive. But if it gives you peace of mind... go ahead, it can't hurt.

Flames, smoke, heat... require stored energy. A fully dumped pack is just an expensive paper weight.
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Old 08-29-2008, 12:16 AM   #12
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IMO - don't goof with discharging the battery. Just take to your local hazardous waste depot and get rid of it.
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Old 08-29-2008, 04:53 AM   #13
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If yourh batt has a lot of use on it - its pretty much done. If it was fairly new, can try charging as nimh at low amps (like 0.5a) and see if voltage will come up. If it does, soon as its above 6v, stop charging as nimh and switch to lipo. Monitor it thru the rest of the charge. How much it takes will give you an idea of how much it was damaged by the overdischarge.

Never leave batt connected, period.
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