Ultra-small batteries powered by viruses
Vnunet.com ^ | 07 Apr 2006 | Iain Thomson
Posted
on 04/09/2006 9:12:00 PM PDT
MIT researchers claim
dramatic performance increases
Researchers at Massachusetts
Institute of Technology (MIT) are using viruses to create tiny batteries that
can store up to three times as much energy as conventional power systems.
The team, led by MIT professors
Angela Belcher, Paula Hammond and Yet-Ming Chiang, genetically modified a virus
so that it attracts cobalt oxide and gold, and assembled the metals into
ultra-thin wires just six nanometres in diameter.
The viruses can be cloned to
assemble lithium batteries ranging in size from a grain of rice to a full-sized
product.
"Once we have altered the
genes of the virus to grow the electrode material, we can easily clone millions
of identical copies of the virus to use in assembling our batteries," said
Professor Belcher.
"For the metal oxide we
chose cobalt oxide because it has very good specific capacity, which will
produce batteries with high energy density.
"This allows it to store
two or three times more energy for its size and weight compared to previous
battery electrode materials. And adding the gold further increased the wires'
energy density."
Furthermore the viruses do not
need a special environment and the reaction takes place at room temperature,
lowering the production costs of any virus assembly system.
Experts estimate that current
battery technology performance improvements will be limited to around eight per
cent a year, but this new technology could lead to a dramatic improvement in
these figures.
The energy density of current
batteries is a major sticking point in the development of long lasting laptops
and electric cars.