Nickel-foam-supported carbon-nanotube electrode offers improved performance for lightweight lithium batteries

February 26, 2014
Nickel-foam-supported carbon-nanotube electrode offers improved performance for lightweight lithium batteries
A nanotechnology-based electrode that resists deformation and electric polarization may one day boost the driving range of electric and hybrid vehicles. Credit: omada/iStock/Thinkstock

Lithium–oxygen batteries are innovative devices that generate power from atmospheric oxygen trapped inside porous, carbon-based electrodes. These batteries are significantly lighter than traditional lithium-ion batteries, and thus have the potential to extend the driving range of electric and hybrid vehicles. However, many practical challenges remain for lithium–oxygen batteries, most notable of which is the buildup of insoluble lithium peroxide by-products in the carbon electrode, which can cause the battery to cease operation after only a few charge cycles.

Now, Zhaolin Liu from the A*STAR Institute of Materials Research and Engineering in Singapore, in collaboration with Aishui Yu and co-workers from Fudan University in China, has developed a carbon nanotube that can alleviate recharging problems in lithium–oxygen batteries, thanks to a support made from three-dimensional nickel foam1.

In previous efforts to improve the performance of lithium–oxygen batteries, researchers investigated numerous types of permeable carbon electrodes—including high-surface-area charcoal, graphene and porous aerogels. Such approaches, however, rely on glue-like binders to hold the carbon particles together. These binders decrease oxygen diffusion rates through the electrode and can degrade and clog pore spaces.

Liu and co-workers set out to design a binder-free electrode by turning to nickel foam, an inexpensive substance with a porous three-dimensional structure that makes it both rigid and lightweight. To ensure the foam's compatibility with lithium–oxygen batteries, the team grew carbon nanotubes doped with small amounts of nitrogen directly on its surface. Nitrogen-doped carbon-nanotube electrodes have been shown to possess catalytic activity that boosts battery lifetimes, and the team anticipated that they could create improved devices by supporting these nanomaterials with nickel foam.

Using chemical vapor deposition, the researchers were able to cover the nickel foam with layers of doped nanotubes arranged in typical bamboo-like structures. These nanotubes were loosely packed and contributed to a network of large, interconnected tunnels throughout the foam. According to Liu, these tunnels facilitate oxygen diffusion and provide critical voids where can be deposited without limiting battery performance.

When they measured the performance of their binder-free electrode, the team found that it could deliver twice the electrical capacity of a pure-nitrogen-doped electrode. Liu notes that the strong electrical contact between the nanotubes and the nickel support suppresses volume expansion and limits the polarization effects that hinder recharging. "The next step will be to apply these electrodes in real lithium–oxygen batteries," he says.

Explore further: Progress made in building rechargeable lithium-air battery

More information: Lin, X., Lu, X., Huang, T., Liu, Z. & Yu, A. "Binder-free nitrogen-doped carbon nanotubes electrodes for lithium-oxygen batteries." Journal of Power Sources 242, 855–859 (2013). DOI: 10.1016/j.jpowsour.2013.05.100

Related Stories

Progress made in building rechargeable lithium-air battery

July 20, 2012

(Phys.org) -- Researchers in the United Kingdom have taken another step towards proving that so named lithium-air (Li-O2) batteries might one day become practical. Up to now the problem has been using the technology to build ...

Team observes real-time charging of a lithium-air battery

May 13, 2013

One of the most promising new kinds of battery to power electric cars is called a lithium-air battery, which could store up to four times as much energy per pound as today's best lithium-ion batteries. But progress has been ...

A nanoscale glimpse of batteries in action

September 13, 2013

Lithium–oxygen (Li–O2) batteries are a new type of experimental battery that electric car manufacturers are hoping will address the issue of limited driving range. Unlike the lithium-ion batteries used today, lithium–oxygen ...

Inexpensive material boosts battery capacity

October 23, 2013

Battery-powered cars offer many environmental benefits, but a car with a full tank of gasoline can travel further. By improving the energy capacity of lithium-ion batteries, a new electrode made from iron oxide nanoparticles ...

Nanotechnology gives a boost to next-generation batteries

October 25, 2013

Non-aqueous lithium–oxygen (Li–O2) batteries could store energy at densities rivaling gasoline. Commercializing this emerging technology, however, will require breakthroughs that will allow the batteries to be recharged ...

Battery development may extend range of electric cars

January 9, 2014

It's known that electric vehicles could travel longer distances before needing to charge and more renewable energy could be saved for a rainy day if lithium-sulfur batteries can just overcome a few technical hurdles. Now, ...

Recommended for you

Reshaping the solar spectrum to turn light to electricity

July 28, 2015

When it comes to installing solar cells, labor cost and the cost of the land to house them constitute the bulk of the expense. The solar cells—made often of silicon or cadmium telluride—rarely cost more than 20 percent ...

Meet the high-performance single-molecule diode

July 29, 2015

A team of researchers from Berkeley Lab and Columbia University has passed a major milestone in molecular electronics with the creation of the world's highest-performance single-molecule diode. Working at Berkeley Lab's Molecular ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.