A Battery That Runs on What?

There's a new type of battery on the shelf in Japan. When it runs low on power, you can recharge it -- but first you'll have to pee in a cup.

The "Non-Pollution Power" (NoPoPo) battery comes with a dropper and can be recharged using a variety of bodily fluids, including urine, blood, tears, and semen.

To make the battery, Japanese inventors soaked a piece of paper in a solution of copper chloride and sandwiched it between strips of magnesium and copper. This sandwich was then laminated between two sheets of transparent plastic. When a drop of urine is added to the paper through a slit in the plastic, a chemical reaction takes place that produces electricity.

It turns out that urine and other bodily fluids contain many ions (electrically charged atoms), which enable the electricity-producing chemical reaction to take place in the battery. (Who knew?)

The battery, which so far is available only in Japan in AA and AAA sizes, loses a little bit of power each time it is recharged, and it can only be recharged three to five times before it must be thrown away. Still, it's a greener option than most batteries, because it contains no mercury or other harmful materials.

Sort of brings a whole new meaning to the phrase "battery backup," doesn't it?

— Tim Wilson, Site Editor, Dark Reading