Virus-run batteries

Building on studies of seashells by the seashore, scientists at the Massachusetts Institute of Technology have harnessed genetically engineered viruses to build nanoscale components that could lead to a new generation of powerful batteries that are as small as grains of rice and that spontaneously assemble themselves in laboratory dishes. In PhD work done in Santa Barbara, California, Angela Belcher had figured out how ocean-dwelling abalones construct their tough shells from calcium carbonate, a soft chalk. She found that the abalones produce proteins that force the chalk molecules into a different, and much stronger, orientation. Now Belcher is applying that principle in the lab.

She grows viruses bearing novel proteins on which atoms or molecules spontaneously arrange themselves in desired ways. In her newest work, done with co-workers at MIT, Belcher sought to arrange metal atoms in ultrafine patterns so they could serve as the part of a battery called the anode, a steady source of electrons. Her team started by altering a gene in a common virus. The mutant viruses make novel protein sheaths that naturally grab tiny particles of cobalt oxide and gold8212;materials that can beef up the charge-carrying capacity of lithium ion batteries. When spread on a special polymer surface, the viruses and their metallicised sheaths naturally arranged themselves in perfectly ordered layers8212;an arrangement that can serve as the guts for a powerful new kind of battery, the team reported in Thursday8217;s online edition of the journal Science.