ALD could help prolongue battery life and improve reliability

Left: A boron nitride nanotube coated with a 10 nm conformal layer of aluminium oxide  (a bright-field TEM image); Right: energy-filtered image with elemental contrast (green – oxygen, red - boron).

November 2014

Improving the charge and life-span of batteries in phones, laptops and household technologies has the potential to improve not only efficiency and flexibility of these technologies, but also minimise the amount of toxic landfill created every year as a result of disused batteries.

MCN Technology Fellow, Dr. Alexey Glushenkov has been working on electrode materials for lithium ion and sodium ion batteries as well as electrochemical supercapacitors. A recent trial as part of this project saw a conformal deposition of 10nm of aluminium oxide onto boron nitride nanotubes by Atomic Layer Deposition (ALD). A normally challenging structure to coat uniformly, the nanotubes were coated by a homogeneous, 10nm thick layer of aluminium oxide using MCN’s ALD Savannah S100 instrument. The ALD techniques available at MCN are able to achieve highly conformal, continuous, pin-hole free depositions on complex surfaces and porous structures.

Dr. Glushenkov is aiming to use a similar technique to provide coatings for electrodes in batteries to provide an artificial surface layer to separate electrodes from direct contact with electrolytes in batteries. Such a surface layer is capable of ionic conduction and does not interfere with battery operation, while it works to reduce unwanted side effects caused by the contact of electrodes with electrolytes and result in better cyclic stability and reliability of batteries.

This project holds great potential for revolutionising the portable electronics industry and the way we interact with our devices.