We are actually not so far away from hitting the ceiling with batteries. There are fundamental physical reasons for why you can't put much more than 1eV per atom in a battery. That equates roughly to 850 Wh/kg, if memory serves, and we are currently pushing Li-ion towards 300 Wh/kg. So we can only keep growing at 5% for another couple of decades or so. Regardless of battery chemistry.

What people often do to hide this fact is talk about energy density, Wh/L, where growth can continue for longer, at the expense of making batteries heavier.