Lipo draining unbalanced?

[spawn_x]

Hey guys, have a question. One of my lipos is doing a weird thing - it charges up pretty balanced (using a balancer of course) but when draining, one cell gets to 2.7 the other stays at 3.5

what would cause them to drain like that? I would like to get it solved

I read that it might be because of a bad connection on one of the packs?

[spawn_x]

bump

[Bermbuster]

Originally Posted by spawn_x

Hey guys, have a question. One of my lipos is doing a weird thing - it charges up pretty balanced (using a balancer of course) but when draining, one cell gets to 2.7 the other stays at 3.5

what would cause them to drain like that? I would like to get it solved

I read that it might be because of a bad connection on one of the packs?

the mfg of the pack didnt use matched cells in your pack can be the cause.
are these series or parallel cells?

[Duster_360]

Do you have a lot of cycles on it?

Regardless, it sounds like that cell is going bad. Reason - no telling, poss this cell and the other are very poorly suited to run together and thats not helping the weak cell, could just be a little poorer quality cell to start with.

Going to 2.7v is poss damaging it even more, some cells can't take discharging that low. I don't let mine go below 3v.

[spawn_x]

series or parallel - not sure? Its a 2 cell 7.4volt, so I guess series?

It does NOT have a lot of run time on it. They do charge up to the same voltage pretty much

It is a poor quality battery probably, 20 dollars shipped for 1800mah 7.4 (ebay)
http://cgi.ebay.com/ws/eBayISAPI.dll...m=180346819680

I'm going to warranty this one I guess

Do you guys think the cheap lipos on ebay are no good?

[pakk]

I have cheap lipos with no problems. I can't tell the difference between them and my expensive lipo, but I run my lipo cut very high.

--pakk

[burnineyes]

Same here, I run several lipos. Some cheapos and some good ones. Using a 3.4V/cell cutoff I cant tell the difference in power, runtime, or balance.