What about the weight of the entire drive system? Still not the same thing, as the weight of batteries doesn't change as you drive. Not sure, as a quick search doesn't give me the right data, but it seem like the ICE setup requires more engine/exhaust etc. weight, so it seems likely the amount of efficiency required for batteries is less than gas at the current tech level.
Last time I tried to estimate that it seemed with a passenger car you get some win there that offsets the battery weight. Something around 300lbs. My guess is if batteries got 30% more power dense the weight penalty would disappear. Part of that is as the weight of battery drops you can make the rest of the car lighter as well.
