Oh, I might add, the 'urine powered' batteries is hardly a new thing. I saw my first commercially available one thirty years ago, and remember seeing home made ones 45 years ago when I was a kid.
"Oh, I might add, the 'urine powered' batteries is hardly a new thing."
Right you are. Any acid will work as an electrolyte with the proper electrode materials.
Writer (as usual) deficient in basic science knowledge.