[jhautz]

Not sure I know the answer to what temp to low is.. but I do know that if you are running a pack that is cold... 50 degrees F outside and the pack is at air temp it has noticeably less punch. The internal resistance goes up the lower the temp which makes it less capable of delivering current effectivly lowering it true C rating at the lower temps. I tend to be on the safe side. What I have found to be a good solution in the colder months when I want ot run is a couple of those hand warmer bags (the ones when you break the seal inside they heat up for an hour or 2.) I toss a couple of those in a small cooler and keep the lipos inside there untill I'm ready to use them.