[Al Skierkiewicz]

Win,
The cells with reduced capacity that are shown in Ether's post and my discussion are cells that for one reason or another have some of the plates within the cell damaged or detached. The change in internal resistance is very small but the cell has less available power density and so it dies out sooner than the other cells. I recommend that teams do not try to pull 200 amps from a battery for extended lengths of time. Yes, robots do pull more than that but it is for much shorter periods of time. (except in extended pushing with another robot) The effects of this high current, extended test, is to warp the internal structures of the cells and raise the internal temperature to the point where cell relief valves vent the higher pressure (and water vapor) to atmosphere. I also believe that the separator (absorbed glass mat) may become damaged as well producing another type of internal resistance that discharges the cell constantly. In these batteries, the terminal voltage will fall in multiples of 2 volts after sometime (several hours to a few days) from being removed from the charger. All of the test methods including a voltmeter will show this defect when the cell has become completely depleted. In worse case events, the discharge is extreme enough to cause heat, leakage, case swelling and steam.
Above all, remember that our batteries have a stated life of only 400 charge/discharge cycles under optimal conditions. Our severe use cause this life to be reduced to perhaps 300 cycles or less.