Hey guys~

One of my 4s 5000mAh packs is acting funny. It charges just fine and reads perfect when tested. The problem is that the battery has NO punch when I run. I am thoroughly confused for my Hyperion charger does not alert me of any issues either. Any help would be greatly appreciated, thanks!

You may have a internal connection prob - connection has come unsoldered, but the wire is sitting on the cells solder tab - lets you ck voltage and charge and etc, but when its stressed - ie load put on it, the connection is iffy enough that it fails to deliver.

Sounds like you may want to take pac apart and see if connections are sound. That'd be the 1st thing I'd look at given the behavoir.

Thanks! The pack had a lot of air under the shrinkwrap. The cells were not puffed by the altitude in CO made the air under the shrink wrap "casing" was enough that it must have been placing enough pressure to cause the issue. A small slit in the underside and all is well. Ran great today after 2 charges. I will be keeping my eye on it but behaves fine so far! Weird.