An enzyme-catalysed battery has been created that could one day run cell phones and laptop computers on shots of vodka. The key to the device is a new polymer that protects the fragile enzymes used to break down the ethanol fuel, scientists told the American Chemical Society’s annual meeting in New Orleans on Monday.



Enzyme-based batteries have the potential…


to be cheaper than fuel cells that rely on expensive platinum or ruthenium catalysts. “It sounds great,” says Bob Hockaday, founder of the company Energy Related Devices and designer of a methanol-powered battery. “Enzymes are inexpensive and catalytically very active.”



Fuel cells work by converting into electricity the energy released when oxygen and hydrogen react to produce water. Pure hydrogen is an explosive gas and difficult to store, so fuel cells often use a chemical source. Ethanol is used in Minteer’s cell, and the enzymes strip off the hydrogen.



But the enzymes are sensitive to slight changes in pH and temperature and can rapidly degrade and become inactive. Until now no bio-battery had enzymes that lasted for more than a few days.



Specially tailored pores



The typical approach to solving this problem has been to immobilise the enzymes by attaching them to the fuel cell’s electrodes, but they still tend to decay…



More here.