There is no "automatic protection" for dumb sailors possible which would
work by itself and would "avoid lightning" or "protect" the boat. At least, not for modern boats with loads of electronics.
Nothing in the World is able to stop MILLIONS of volts which lightning strike consists.
There are few factors which must be taken in consideration.
1. Each
cabin on the boat must be designed and built by boat
builder as real Faraday cage. Therefore boat must be aluminum/steel, it's impossible to create real Faraday cages on
fiberglass boat. I'm also positively sure that idea of "whole boat as one big Faraday cage" will not work.
2. Each
cabin (Faraday cage) must have quick disconnect for ALL wires coming into this cabin. By "quick" I mean matter of seconds, not minutes. All connection points must have ability to be closed with special fitted metal plates so there will be CONTINUOUS Faraday cage.
3. Nav station also must have metal housing, removable metal cover and also must have ability to be disconnected COMPLETELY in a matter of seconds to become fully sealed Faraday cage.
4. Same for
engine rooms.
5. Same quick disconnect must be for ALL wires going to the
mast, except one very thick cable which should be routed to the
water, to properly engineered dissipating system, to help dissipate energy of lightning strike.
So preparation for storm will consist disconnection of ALL connectors, totally depower the boat and turn all cabins into SEPARATE Faraday cages. All
equipment on the mast will be destroyed in case of lightning strike, but most of other
equipment (that's 100's of thousands $ on modern boats) should survive.
Will this disconnection work be a hassle? Yes, at some degree. Would you do it? What if it will save you $100K one day?
It's very well known fact that cell phones and laptops (very sensitive devices) easily survive lightning strikes if they been inside microwave. Microwave is Faraday cage.