Taking Electrons for a Spin

Stewart Barnes has been collaborating with researchers in Japan for more than a decade to advance the field of “spintronics,” which explores manipulating an electron’s magnetic movement, rather than its charge, to operate electronic devices.

They propose that a spintronic battery (“spin battery”) could offer several advantages over conventional batteries, which generate electricity through chemical reactions.

“With a spin battery, your hoverboard would never catch fire,” says Barnes, a physics professor at the College of Arts and Sciences at the University of Miami, referring to reports of fires sparked by faulty lithium-ion batteries in the popular toy.

In addition to the safety advantages of having no flammable chemicals, Barnes says a spin battery would last longer and therefore be more cost-effective than chemical batteries. “Charging” causes the boundary between different phases to move, rather than a flow of ions back and forth between electrodes that break down in the process.

A longer-lasting, safer, less-expensive battery could propel an eco-revolution, making electric vehicles more affordable and offering a better way to store wind and solar energy for 24-hour use.

Barnes and his team have proven—through theoretical mathematics—that the spin battery is a viable alternative to the lithium-ion battery. They’ve also built a tiny model, no larger than a human hair in diameter, with nano-sized magnets that produce a small voltage in response to a magnetic field. They are seeking funding to translate their discoveries about spintronics into a working energy storage prototype.

“Good science works on simple principles,” says Barnes, who published the spin battery technology in a 2009 issue of Nature. “You have to start off with the fundamental science. Once you have a sound explanation for how a phenomenon works, only then can that area develop into something that’s useful for humanity.”

- Meredith Camel / UM News