Sorry but you may want to read a bit more on true/genuine A123 cylindrical cells. They DO NOT PUFF. They cannot physically puff. they Will vent first in extreme abusive situation such as severe physical damage or excessive over-voltage charge. ALL my current jets (BVM Bandit MK II, Ultra Flash, BVM Bobcat, Comp Arf Spark) all have these genuine A123 cylindrical cells. Per spec they are recommended to be stored fully charged. In the past, after one year of storage I have barely put it 20-30mAh charge in a 2300mAh 2s packs,

Here is some info to start with.

http://hangtimes.com/a123_batteries_for_giants_faq.html