Re: turrets, autoloaders etc are electric anyway
Larger tanks often have an auxiliary engine to generate electricity so they don't have to run the main engine to do so. IIRC, the Centurion used a 1,000 cc Austin or Morris engine to do the job, though their crews often complained that it was the most unreliable part of the entire vehicle so they'd end up having to use the 27 litre main engine to generate electricity. Smaller tanks like the Scorpion didn't, which is why their nice E-type engines were often shagged out in fairly short order due to running them at full speed all the time to keep the turret's batteries charged up.
I know that Ferdinand Porsche was obsessed with electrical drive systems, typically involving air-cooled petrol engines, but they seldom worked that well. Whereas Merritt's regenerative steering did: its only fault was the fancier controls he tried to implement when it made its debut on the Churchill which just added more things that could break (and did), which is why British tanks reverted to brake levers thereafter, but still connected to the new steering unit that could do fancy stuff like turning on the spot; shown to good effect with Comets managing to navigate the twisty little roads in German villages where the Shermans got stuck. He wryly observed that the Germans copied the system from a captured Churchill and their implementation on the Tiger et al made it more complicated. With the anticipated results.