>>Electric motorcycles actually lead to a larger conversation about more lethal electric vehicles, like electric tanks, on the battlefield.
The Abrams-X is a step in that direction. It's billed as a 'hybrid' but can run full-electric when it needs to be quiet. I haven't seen a lot about its powertrain (other than it is not a turbine) but I'd expect it to be electric motor driven with a powerplant providing electricity much like a diesel-electric locomotive, but with the addition of batteries allowing some runtime without using the ICE.
Speaking of diesel-electric, check Edison Motors in BC. They're a couple of off-road truckers designing and building the truck they want. Their first prototype used a Cummins diesel generator coupled with dual eklectric transaxles, but I think they've moved on to Saab/Scania for ICE. Diesel-electric is a painfully obvious approach when you need bags of torque.
In both cases, I expect the new sodium based battery tech will play a part. Less efficient per lb than lithium-ion, but longer battery life, cheaper to make and they're not explosive(!)
Just my $0.02 - but there are interesting things happening in this area...