Dave, based on the chemisty of this battery, I would say your dealer is thinking about a different chemistry like NiMH. Just like NiCd's liked to be completely discharged before recharging them. Different chemistry so the thoughts do not hold true. As for 220v versus 110v, considering the onboard charger is 3.3kw and the battery can discharge at 180kw, I really don't think 220v versus 110v is going to make much of a difference for C rate damage, and I haven't read anything on charging time causing damage. Perhaps, the fact that 220v is putting more force behind the charge that it can better withstand some sort of backforce that the battery may produce makes it a better charge? I am not an electrical engineer, but I know there is some type of resistance to taking a charge, just like electric motors produce a back current of sorts. Regardless, I think most people are going to make the decision to go either 110v or 220v based on the turn around time that they need or want the car. Eventually, I would imagine all of use will use 110v at some point during the car's life because of the lack of availability of 220v