'Spin' battery could power more efficient cars, computers

A team of researchers from the US and Japan say a new type of battery — the “spin battery” — could lead to the development of more energy-efficient cars and computer hard drives with no moving parts.

The battery would be charged with a magnetic tunnel junction, which applies a large magnetic field to nano-magnets in the battery to convert magnetic energy directly into electrical energy.

The process produces a battery better than any known chemical battery, according to Stewart E. Barnes, a physicist at the University of Miami.

“We had anticipated the effect, but the device produced a voltage over a hundred times too big and for tens of minutes, rather than for milliseconds as we had expected,” Barnes said. He added that the potential applications for such technology are endless.

“There are magnets hidden away in many things, for example there are several in a mobile telephone, many in a car, and they are what keeps your refrigerator closed,” Barnes said. “There are so many that even a small change in the way we understand of how they work, and which might lead to only a very small improvement in future machines, has a significant financial and energetic impact.”