This would also be amazing for electric aircraft, as capacity to weight ratio is the main thing holding them back.
I'd imagine there could be military applications too, once the energy density is high enough to be useful. If you have, say, a bunch of tanks that can run off of diesel or batteries, then you can recharge them opportunistically whenever power is available (i.e. if you're defending a city that still has functioning utilities) and save the diesel for when you have to move long distances. Basically, it makes the fuel resupply logistics more flexible, and it reduces costs and climate impact in peacetime if exercises are conducted mainly on batteries.
This would be a great use case for space-based microwave solar though (if it ever gets off the ground).
https://en.m.wikipedia.org/wiki/Oil_campaign_of_World_War_II
which is probably part of the reason the US Army is so big on renewables.
Odessa in Ukraine doesn't have gasoline or diesel. They do have electricity though and people with EVs are driving around just fine - even an electric Taxi.
Gasoline distribution points (gas stations) tend to also blow up in a pretty ball of fire when attacked.
An EV can be charged from any socket with working power.
AKA "specific energy", usually measured in kWh/kg or MJ/kg.