Deep Cycle issue

[Craig Thompson]

Beautiful, almost cool, 70f degree day while deep cycling six tb48s..

Had warning set to 15% and critical at 10%. All batteries charged to 100%.

Four battery drains were perfect. Kept her up about 6-8 inches until all cells were just below 3.3

On two of the batteries though both at about 40 total charges, I received a warning, "Overheating During Discharge".

One right at the 3.34 range and the other just a little higher, battery temp was at 69c-71c.
One of them just dipped below 3.30 across the six as I brought it all of the way down.
The other completed turned off and dropped about 8 inches. No damage, however obviously now wary of both batteries.

Any thoughts or insight is appreciated.

 

[The Editor]

Answered via PM.

 

[Steve Domigan]

Answered via PM.

Why by pm and not public forum?

 

[Craig Thompson]

Why by pm and not public forum?

Hey Steve, I know that sounded weird, but nothing to hide. just had a offline conversation. Here are the responses.

I wouldn't worry too much. It's perfectly normal for lipos to rise in temp when you are working them daily hard at the end of their discharge curve.
You just peaked over the high temp warning level and got the warning.
So long as you let them cool to ambient before charging they should be fine.
Just keep an eye on the two packs in question and once you have two or three flights under your belt you can 'trust' them again.

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