I would also quite like to know about this, I have one Panasonic doing this on a much larger scale, no warping or chips, just what seems like condensation between the wrapper and the bottom body (negative casing) of the battery. Could be a hot pocket on a normal day, have just noticed it today. No weird perf or anything. There is no casing damage whatsoever that is visible from outside. I will be taking off the wrapper soon, checking, and rewrapping if the casing is intact.