Here's my question. Any hard case lipo like the Trackpower and Team Checkpoints that have clear shrink wrap on them, how will you know if you puff a cell?? If there was no wrap I would assume it would split the case and you would see that it's puffed. I can't see a puffed cell spliting the wrap and if it does that far I think your at a point you got big problems no?

Another question, All batteries eventually reach then end of their life, what happens when a lipo is simply "used up"?

Well even with the clear shrink wrap you should notice the seems starting to separate on the battery case if a cell is puffing, they puff up fairly big. As far as when a lipo is "done" you'll notice it just won't have the power it normally had. At least thats been my experience when they reach the end of there useful cycle.

When the hard case Lipos decide to puff up, it will split the case open. They have a decently tight fit inside so even the tiniest bit of swelling and they split the case.