They don't get close to E
I was just looking at weights:
V6 vehicle weighs 3500 lbs and motor weighs maybe 400 lbs. An EV weighs 4000 lbs with a 1000 lb battery. Each with a roughly equitable 250HP, and 300 lbs/foot of torque for the EV and 250 lbs/ft for the V6.
A 70T M1 tank turbine looks to weigh 2500 lbs and provides 1500HP and 3900 lbs/ft of torque.
If I just extrapolate, the M1 battery would weigh 6X (6000 lbs) to achieve an equitable HP and 13000 lbs to achieve equitable Torque.
Now obviously torque is very important to a lumbering 70T tank. But imagine trying to maneuver thousands of 13000 lb batteries and installing them anywhere. Of course, a vehicle will be required to bring those batteries to the front with some loading mechanism, with armor weighing even more and protecting the integrity of the NBC of the tank.
Then the dead batteries will need to be returned and recharged, using as many amps to return back as to the tank. And of course the battery deliverers will need their own batteries. I cannot imagine the charge time for a battery of so many amps, so might as well set up a power plant at the Fuel Depot.
Now that is a juicy target.
Now to the weight of gas, diesel, or aviation kerosene, which incidentally the M1 can run on all 3..... About 7 lbs per gallon. So an equivalent energy output can be achieved allowing one EV recharger to deliver one 13000 lb battery as opposed to completely fueling 3+ tanks and go back fast and lighter empty.
Like I said stupid.