Re: I would have thought ...
"a plug and socket arrangement that could withstand immersion in salt water"
That's far more difficult than you think it is. Seawater is really hard on many materials and is fairly conductive. It's hard enough designing a high-power plug and socket arrangement that works reliably and robustly in when there's a trained person there to carefully plug and unplug it in air. An autonomously operated plug/socket submersed in seawater is a nightmare.
Some sort of near-field inductive charging system sounds way easier to me...
Biting the hand that feeds IT
