Angela Belcher holds a display of the virus-built battery she helped engineer. The battery - the silver-colored disc - is being used to power an LED. Credit: Donna Coveney
But don’t worry. It is a common bacteriophage. It can infect bacteria but is harmless to humans.
You might find this virus someday in the battery of your plug-in hybrid car.
What has happened is that MIT researchers now can genetically engineer viruses to build the anodes and cathodes of a lithium-ion battery. These batteries have the same energy capacity and power performance as state-of-the-art rechargables being considered for hybrid automobiles. They also might be used to power personal electronics.
The new batteries could be manufactured using an inexpensive and environmentally friendly process, at and below room temperature, and without harmful organic solvents. In fact, all of the materials in the battery are nontoxic.
Three years ago, an MIT research team led by Angela Belcher engineered viruses that could build an anode by coating themselves with cobalt oxide and gold and self-assembling to form a nanowire. Cathodes are more difficult to build because they must be highly conducting to be a fast electrode. MIT professors Gerbrand Ceder and Michael Strano genetically engineered viruses that first coat themselves with iron phosphate, then attract carbon nanotubes to create a highly conductive material.
Incorporating carbon nanotubes increases cathode conductivity without adding much weight. The new batteries can be charged and discharged 100 times without losing capacitance. This is fewer cycles than current lithium-ion batteries, but Belcher expects them to be able to go much longer.