As the title says (and yes, I know it sounds a bit weird), what's the best way to make a warmable metal plate (70*45 cm big), using electrical warming? I've been thinking about using induction heating to make the plate warm, but I don't know the best way to do it. It should be battery driven and also have a switch, but that's basically the only components that I want the plate to have. So what's the best way to make it? And also, I would appreciate a simple circuit diagram.