Ah (Amp hours), get your Units right Man, UNITS!!!
I'm a bit of a pedant about that sort of thing.
We manufacture electrical control panels and I try to make sure that anything that goes out to a customer is accurate. kW, not Kw, kVA,etc., but I routinely get quotes in from transformer manufacturers where they get it wrong.
Today 480v instead of 480V. 670 amps instead of 670A.
As I'm sure, like many others here, I post on other forums. Frequently there is confusion between energy and power. For people not in the electrical field that's possibly understandable.
But this is an electrical forum. We ought to be able to get the units right, right?
Back to the brushless motor thing. We make brushless motors. These are mainly for the machine tools industry. High speed capability and low inertia to power ratio is why they are used for that application - 10,000 rpm to zero in half a second to within +/- half a degree position accuracy.
The other attribute is their very high efficiency - better than 97%. That's where the longer battery life comes in. But cost may be an issue. The magnets are expensive.