This is highly interesting -- for one; once the technology improves and becomes productionizable; it has the capability of making light aviation aircraft actually somewhat affordable to the general public -- or... in a round about way; making electric boats much cheaper.
One of the biggest costs of a plane or boat is the fuel -- at the MoCo AirPark last week; the prices were:
Jet A Full Service: $5.99
100LL AVGAS Full Service: $6.60
A simple Cessna 172 needs 56 gallons; so a full fillup is $369.60; giving you a cruise range of 500 nautical miles -- meaning that flying from Montgomery County MD to Ocean City MD and then back again (300 n.mi total due to the need to fly a odd course to avoid the Washington DC ADIZ) sets you back $220~ bucks.
Then there's the cost of maintenance.
Electrics promise to be significantly simpler to maintain than a AVGAS piston engine system.
Boats are almost as bad -- a Bayliner 266 Discovery has a fuel capacity of 81 gallons yet gets about 175~ miles on that -- marine gasoline is about $3.849 while marine diesel is $3.719 -- so a fill up is in the $300~ price range; meaning if you wanted to cruise from Annapolis MD to Ocean City MD and back via the canal that goes through delaware; it'd be a 150~ nautical mile trip; meaning a round trip would cost $600 bucks.
At least with boats; the batteries can also do double duty as ballast in the keel....
