Doesn't the gasket seal prevent electrical conductivity between the lid and base? This would make it a poor Faraday cage.A better option for protecting small electronics is your pressure cooker. It forms a well-sealed faraday cage, thanks to the pressure gasket seal. .
I try to stay out of the galley, I guess it shows. My wife has just made a whole lot of orange marmalade in the pressure cooker I should have payed more attention.Odviously you haven't been around pressure cookers much. There is plenty of metal to metal contact between the lid and the pot. But you may want one big enough for you and your crew during heavy lightening strikes.
Thanks Sailing dog I wont worry in future. I thought the large gap formed when the main battery switches are off may have been enough to encourage the high voltage to seek an alternative path rather than go via my expensive electronics at least with a nearby rather than direct hit. Hopefully Inside an aluminium boat the electronics receive a little protection from the induced voltage if a strike travels via the hull.It won't help at all....if you get hit...the induced voltages won't care if the equipment is running or off... Most unhardened ICs require an an induced voltage of less than five volts to fry them in many cases...and with a lightning bolt's potential voltage and hundreds of thousands of amps...to drive it, that's relatively easy to achieve.