Ive been building water batteries for decades. They supply non stop power from years to decades even. They are non toxic since the only thing used in them is plain water with no salts or acids. The only down side is the coils may need cleaning once a year or so in something like vinegar to remove any corrosion. I put up some videos of things I have powered on water batteries on my youtube channel at https://www.youtube.com/channe.....YTDtz11xdw