Stories tagged Massachusetts Institute of Technology


While electronic devices double their capacity every 18 months or so, battery capacity per volume are lucky to double every ten years. A new breakthrough by materials scientists at MIT promises to drastically decrease the size of batteries. In a battery, only the surfaces of the electrodes create electricity. The key to making lighter batteries is to make lots of surfaces but minimize the material under the surface - in other words make the electrodes as thin as possible.

Living viruses manufacture paper thin batteries

MIT scientists, professors Angela Belcher, Paula Hammond and Yet-Ming Chiang have used genetically engineered living viruses to assemble thin-film nanowires as the anodes and cathodes of a flexible "battery wrap" only 100 nanometers thick. The virus is a derivative the M13 bacteriophage. It is 6 x 880 nanometers in size.

Three dips will do it

The genetically engineered battery wrap is fabricated by dipping a scaffold into three beakers. The first dip picks up a layer of polyelectrolyte which can be as thin as 100 nanometers. The second dip is into a soup of the 6 x 880 nm viruses. The viruses, which are negatively charged, stick to to the positively charged scaffold kind of like the bristles on a hair brush. These viruses, when dipped into third solution, are genetically engineered to pull cobalt-oxide and gold ions onto their surfaces.

After that, the polyelectrolyte is dried out, and the 6-nm-diameter viruses dehydrate, becoming harmlessly entombed inside a sealed compartment of inorganic cobalt and gold.
"Potentially, when we grow a lithium layer on the other side of the polyelectrolyte for the other cathode, we could use this material to make batteries as thin as 100 nm,"

Paper thin batteries eliminate need for battery compartment

Thousands of these battery layers could be stacked on top of each other and still be paper thin. Such a battery could store two or three times more energy for its size and weight than conventional batteries today. Its "wrapability" would also allow the batteries to be placed around objects rather than requiring storage compartments.

Source:Living viruses create flexible battery film EE Times