There is another problem though -- Braun didn't use old-fashioned
NiCds for the fun of it. The NiMh cells aren't up to the motor's high
current draw while shaving.
I got about 5 shaves out of a charge - should be more than 15.

That doesn't make sense. Like nicads, NiMHs are capable of pumping a lot of
current.

Cells vary in capacity. You can buy NiMH AA cells with 2500 or 2700mAh
capacity. I don't think nicads have ever had that high a capacity.