Researchers Make Safer, Thinner Batteries Using Kevlar

A group of researchers from the University of Michigan may have found a way to make lithium-ion energy packs saver and slimmer by using Kevlar.

The team has developed a protective membrane using nano-fibres extracted from Kevlar, this insulates the electrodes in the battery while still allowing the lithium-ions to pass through to create the circuit. The super thin layers should reduce the chances of a short circuit and also allow for the battery to have more energy.

The researchers made the membrane by layering the fibres on top of each other in thin sheets. This method keeps the chain-like molecules in the plastic stretched out, which is important for good lithium-ion conductivity between the electrodes.

Siu On Tung, Macromolecular Science & Engineering PhD Student and member of Prof. Nick Kotov's research group, shows a kevlar cloth in the NCRC
Siu On Tung, Macromolecular Science & Engineering PhD Student and member of Prof. Nick Kotov’s research group, shows a kevlar cloth in the NCRC

Another feature of this material is it can be made much thinner so more energy can be put into the same sized battery cell, or the entire cell can be shrunk. The University have seen a lot of interest from people looking to make thinner products with this technology, with over 30 companies requesting samples of the material.

While the team is satisfied with the membrane’s ability to block the lithium dendrites, they are currently looking for ways to improve the flow of loose lithium ions so that batteries can charge and release their energy more quickly.