Urine for battery?
A physicist from Singapore has developed a battery powered by urine!! Apparently it was designed for use with disposable medical test kits.
The battery unit is made from a layer of paper that is steeped in copper chloride (CuCl) and sandwiched between strips of magnesium and copper. This “sandwich” is then held in place by being laminated, which involves passing the battery unit between a pair of transparent plastic films through a heating roller at 120�C. The final product has dimensions of 60 mm x 30 mm, and a thickness of just 1 mm (a little bit smaller than a credit card).
Source : MedicalNewsToday