I'm sure that there are plenty of folks here that can make suggestions but I think that if you do ANYTHING to any of the electronics in your car, even just opening the box to look at the circuits, that you're going to void every warranty of every kind that your vehicle has. So if it were me I would pass on this idea, at least until all of the warranties have expired. The one thing that you could do and probably get away with it would be to put a strong surge suppression system to your household's AC system to prevent a power surge from reaching your car's charging system. Your charging system may already have good surge suppression built in so this may not help but OTOH, it won't harm anything either.
A friend of mine bought an electric KIA Kona several months ago and I just rode in it for the first time this past weekend. He charges his from a home solar system and AFIK hasn't taken any special precautions.