Karan Ji, this is far from exhaustive or publication-grade, but here goes:
I was looking into Arjun MBT specs and the possibility of having an electric tank, with drop-and-replace battery packs, of course. The current 1400 HP motor weighs 4299 lbs . It turns out that electric motors in Tesla and from Bosch can easily do 1 HP / lb [2,3]. So a 1400 HP motor pack with 4 electric motors would only weigh 1400 lbs. Electric tank weight savings so far: 2899 lbs.
The Arjun has a 1610 liter diesel fuel tank for a range of 200 km and the fuel alone would weigh 3020 lbs [4,5]. In contrast, the weight of the battery pack in one Tesla is estimated to be 1323 lbs . The weight of 4 such battery packs for a 4-motor system without compromising range would be 5292 lbs.
Electric tank weight advantage = 4299 - 1400 + 3020 - 5292 = 627 lbs or 284.4 kg
In other words, the weight of the tank crew is completely negated.
While I was going to say that considerable radiator weight can be saved when getting rid of an internal combustion engine, I decided against considering that advantage because lithium batteries don't fare well above 45C, so the batteries would need a cooling system anyway and I'm considering no weight advantage there.
I do think an electric tank would have a considerably lower thermal signature though - making it more stealthy against thermal imaging weapons, and be so much quieter. Acceleration and reversing would be so much easier as well.
 MTU engine for Arjun
 Bosch motors
 Tesla weight distribution
 Arjun fuel capacity
 Diesel fuel weight