opinions about batteries....

[zeropointbug]

Nice one, were they stored at storage voltage? Does your charger tell you the iR of the pack as well?

Voltage holding ability or internal resistance (cell iR) of a pack will tell you everything about how a pack will behave actually. The lower the iR, the lower the pack temp will be, simple heating due to voltage drop is how it works. How well the pack handles the temperature increase is due largely from what chemistry it is... ex. A123's LiFe-n-Ph vs. LiPo packs.... A123's can withstand higher temps, without being dangerous.