Lipo Short- What To Do?

[hibbs]

Hello all,

Okay so I am a moron. I made an 'octopus' connector for my charger so I could use one wire for any connection. So my charging stuff was all piled up and I didn't realize the lipo was still plugged in. I plugged in a glow starter too. Basically I think I connected the two batteries together (in parallel?). A sub C battery and a 3s lipo. The charging wire melted and started smoking immediately.

I don't have a voltage checker. I hooked the lipo back up to the charger and let it charge for a min, and it acted fine. Should I toss it? It isn't puffed/didn't get warm or anything. I think I'm going to put it outside. Don't want to lose my house/child over a $20 battery...

Any thoughts?

EDIT: not in parallel it would have been a short with + to + and - to -

[iamsuperbleeder]

parallel is in fact + to + and - to - . a short is when + and - meet in a loop between battery connections, not to be mistaken about + and - meeting at one point to form a series connection

it sounds like things went bad because you plugged a 7.4v nickel battery into a harness that had an 11.1v lipo plugged into it. the difference in voltages between the two batteries being hooked together in parallel would have caused the higher voltage of the lipo to want to flow into the nickel battery, and at MUCH to high of a rate than the nickel battery could have accepted it. I don't know the specs on either battery, but let's say the lipo was 4000mah with a 40c rating, it could have tried to pump 11.1v at 160amps into a nickel battery that might only be rated to take a charge of 2, maybe 3 amps, thus the overload and meltdown of the wire. had the voltages of the two batteries been the same or at least close, it would not have happened (assuming your "octopus" is wired correctly)

as far as the lipo goes, if you can look at the individual cells on the charger and they're all still showing a normal volt reading, I would try to run it down in a car or truck, and then try to charge it back up again (outside, just to be safe) and see that it still holds it's full capacity. there's a chance that all the momentary connection did was lower it's capacity some (excessive heat will cause the same thing), and worse case scenario is it got hot enough quick enough to desolder some of the internal joints on the battery, which I've seen happen and turn a 3s battery into a 2s battery, in which case it will show up when you go to look at the cell voltage on the charger. when that happens, you can risk it and open the pack up and attempt a repair (something most people would not attempt; probably not even myself), or just consider it a loss and dispose of it. as long as the connection was for a VERY short period of time (2 or 3 seconds), there may have been no harm at all

however, I think that you would have damaged the glow starter more than the lipo

[hibbs]

Thanks for the reply bleeder. You are absolutely correct, it killed the glow charger battery. It's a bit worse though because it's just a single cell sub-C. It's only 1.2V. The lipo is a turnigy 4000mah 20-30C. I'm surprised I didn't get more instability from the poor little NiCd. It was very brief. I'd say ~5 sec. Still that's plenty of time to mess stuff up like you said. I don't think the lipo got hot. really only the wire seemed to get hot (prob from 100+ Amps cruising through there).

I took the lipo outside. It's only at a storage charge now. I may just try to top it off and run it to see what happens. Hopefully no fireworks.

Great advice man, you sound really knowledgeable. I appreciate the help!

[BC-Brian]

Originally Posted by iamsuperbleeder

parallel is in fact + to + and - to - . a short is when + and - meet in a loop between battery connections, not to be mistaken about + and - meeting at one point to form a series connection

it sounds like things went bad because you plugged a 7.4v nickel battery into a harness that had an 11.1v lipo plugged into it. the difference in voltages between the two batteries being hooked together in parallel would have caused the higher voltage of the lipo to want to flow into the nickel battery, and at MUCH to high of a rate than the nickel battery could have accepted it. I don't know the specs on either battery, but let's say the lipo was 4000mah with a 40c rating, it could have tried to pump 11.1v at 160amps into a nickel battery that might only be rated to take a charge of 2, maybe 3 amps, thus the overload and meltdown of the wire. had the voltages of the two batteries been the same or at least close, it would not have happened (assuming your "octopus" is wired correctly)

Yea, from the sounds of your scenario this is spot on. Check out the LiPo and be very careful with it, maybe you got lucky. Perhaps think about how you can prevent this in the future...



as far as the lipo goes, if you can look at the individual cells on the charger and they're all still showing a normal volt reading, I would try to run it down in a car or truck, and then try to charge it back up again (outside, just to be safe) and see that it still holds it's full capacity. there's a chance that all the momentary connection did was lower it's capacity some (excessive heat will cause the same thing), and worse case scenario is it got hot enough quick enough to desolder some of the internal joints on the battery, which I've seen happen and turn a 3s battery into a 2s battery, in which case it will show up when you go to look at the cell voltage on the charger. when that happens, you can risk it and open the pack up and attempt a repair (something most people would not attempt; probably not even myself), or just consider it a loss and dispose of it. as long as the connection was for a VERY short period of time (2 or 3 seconds), there may have been no harm at all

however, I think that you would have damaged the glow starter more than the lipo

Based on your scenario this sounds spot on. Check out the Lipo, carefully, doing it outside and away from things that BURN is a good idea
Maybe you got lucky with the pack.

Maybe think about wiring your charger different so it doesn't happen later down the road.

[hibbs]

Yeah, I'm hoping it's still okay. It was really my fault for having things so disorganized. The chargers and lipos in lipo packs were kind of laying all in a messy pile. I just wanted to charge the glow charger real quick. I didn't make sure there were no other batteries connected. I honestly never even considered the possibliity of being able to short the connection like that. I know now, and won't forget it. I just like the convenience of having one wire from my charger that can plug into everything... Lipos, receiver packs, molex, glow charger, etc. Starting a fire, not so much.

Thanks for the help

[iamsuperbleeder]

oh wow, yeah if the glow pack was only 1.2v, then that would have been far worse than if it were a 7.4v pack, lol

p.s., I answered you PM