Boiled Potato Batteries?
Source: MetalMiner, Stuart Burns (6/25/10)
"Will we see a potato battery in Walgreens anytime soon?"
Hebrew University researchers worked with colleagues from U.C. Berkeley to study the electrolytic processes in living matter for various applications, including the generation of energy for self-powered implanted medical devices. In this application, they found using zinc and copper electrodes with potatoes created a current due to electrolysis; but if the potato was first boiled, the current was increased up to 10x. Researchers chocked this up to a reduction in the potato's internal salt bridge.
In fact, any vegetable will do. Potatoes are attractive because they're cheap at 325 million tons per annum, the world's #1 non-grain starch food and are grown in ~130 countries over a wide range of climates. Once used, they biodegrade quickly and, unlike nickel cadmium batteries, leave no hazardous elements behind.
Will we be seeing a potato battery in our local Walgreens anytime soon? Probably not, but anyone traveling in more-remote or disadvantaged parts of the developed world may, indeed, come across potato batteries in the future. Yissum has made the technology available free to economically disadvantaged parts of the world.