Electric motors are great for providing high torque, as needed in an armoured vehicle.
The enormous weight of the necessary batteries is a problem, so today’s invention is to use them outside the tank -as extra or replacement armour.
Refuelling is then just about throwing some batteries away and plugging others in (in parallel).
This would allow any conventional vehicle batteries to be used (not Li ion ones).
If both the road wheels and drive sprockets all had their own motors, this would reduce the size of the vehicle and also make it less vulnerable to local damage.