In 2013, the lithium-ion battery on a Japan Airlines Boeing 787 Dreamliner caused a fire.

Though no one was harmed in the accident, the issues still needed a solution.

Lithium batteries work by moving the ions in the element lithium from one electrode to another. The motion creates a charge imbalance, ultimately causing electrons to move through a circuit and power systems.

To prevent future accidents like the Japan Airlines battery fire, University researchers developed an advanced type of barrier between the electrodes in a lithium-ion battery.

University researchers used Kevlar, the tough material in bulletproof vests, to create the barrier. It stops the growth of metal appendages that can create unwanted pathways for electrical currents to travel through, ultimately disrupting electron flow to the battery’s circuit. The disruption can cause potentially dangerous accidents.

Kevlar’s heat resistance can also help make batteries safer because the membrane material is more likely to survive a fire than types of materials.

Chemical Engineering Prof. Nicholas Kotov wrote in a release that unlike previously used materials, Kevlar is an insulator.

“This property is perfect for separators that need to prevent shorting between two electrodes,” Kotov said.

To market their product, the researchers founded Elegus Technologies in Ann Arbor.

University alum John Hennessy, Elegus CEO and co-founder, said the project emerged from the University’s Masters in Entrepreneurship program.

“A lot of people want to make thinner and thinner batteries, but the components to do that are very hard to make,” Hennessy said. “If you can safely make a battery thinner and put more energy in it, that’s very desirable.”

The battery fires on the Boeing 787 were thought to have started by lithium atoms transforming into “dendrites” — fern-like structures that can poke through the battery membrane. If these dendrites reach the electrode, the electrons have a path into the battery and can short out the circuit.

The Kevlar membranes developed at the University are large enough to let individual lithium ions pass, but small enough to block the tips of the fern structures.

Dan VanderLey, who helped found Elegus through the University’s of Entrepreneurship program, wrote in a release that the material is special because it can be made very thin.

“We can get more energy into the same battery cell size, or we can shrink the cell size,” VanderLey said. “We’ve seen a lot of interest from people looking to make thinner products.”

Mass production for the battery is expected to begin at the end of 2016. So far, 30 companies have requested samples of the material.

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