A team of engineers at MIT has harnessed viruses to make components for a remarkable new kind of battery, half the size of a human cell and far more efficient than your usual AAA.
The researchers used a threadlike virus that had been genetically engineered so that electrically conductive materials, such as cobalt oxide, would bind to its surface. Because the long, thin virus has so much surface area relative to its volume, it can pack a lot of charge into a little space. The metal-coated microbe can thus be used to build energy-storage devices with a power density much higher than that of traditional batteries, says Paula Hammond, a self-assembly expert who helped develop the technique.
Although the viruses eventually degrade, the metal structure they create [subscription required] remains behind. That structure is strong enough to be transferred and embedded into another surface. So far, the team has succeeded in creating a battery with one virus-built terminal and one conventional terminal, and it is working on a battery with both terminals virus-built.
Microbatteries could potentially power all kinds of miniaturized electronics, including tiny medical implants. “This whole idea of building a battery being a heavy, dirty chemical process doesn’t have to exist,” Hammond says. “We can imagine printing batteries onto different surfaces.”
