One simple way is to use a galvanized garbage can with a tight fitting lid. You would also want to use a hot wax gun and seal where the lid and bottom connect, with the wax. It would also be of use to get some kind of metal mesh about 3 to 4 inches and try to solder that around the edge of the lid and bottom, to make sure you have a good electrical connection. Or use aluminum foil and duct tape. This is a simple, easy to find parts, way to protect you small electronics. Like laptops, printers, solar cells, UPS, chargers, spare electronics for vehicles, etc
