They probably won't. Unless it will cut costs and allow for speed of refilling/recharging. Maybe in another 50 years. And only if one of the big firms tries to sell them something. Lockheed or Boeing or so on. The problem is troop transport needs to be fixable by a shop of people ranging in age from 17 or so to around 25. Inexperienced people. In a fair few cases with hand tools. To even remove a battery from an EV right now you need a lift of some kind and something stable to drop it onto. You can't carry that into the desert. Certainly not onto an aircraft carrier. And we're awhile away from building it into war ships, even smaller ones. The output and range would have to be reliable. A pilot can't rely on a bingo that doesn't accurately tell him if he has enough fuel to get to the target and back.