LIthium-air batteries get nanofibre storage boost

Researchers at MIT have devised a method of high density lithium-air battery production that is “several times” more effective than conventional ones.

Lithium-air batteries have been in development for some time now and are being touted as a replacement for the lithium-ion ones currently found in many devices such as mobile phones.

For example IBM’s researchers have been looking towards the technology which can offer significantly more energy per pound than is currently possible.

And the MIT researchers have managed to create a lithium air battery that is able to cram even more energy into a smaller space.

Following work that has been conducted at MIT last year, the team has been looking into the ability to replace weighty solid electrodes in lithium-ion batteries with porous carbon electrodes.

These carbon electrodes have now been souped-up,  with the team looking towards carbon-fibre-based electrodes that are almost as porous as the average Premier League striker’s brain.

This means that it is possible to more efficiently store lithium oxide that fills the pores as the battery discharges.

According to the team the porous nanofibres were created with a chemical vapour deposition process, creating “carpet like arrays” which provide a “highly conductive, low-density scaffold for energy storage.”

The team was able to create such a material that was composed of “more than 90 percent void space” and minimise the amount of carbon weight in the electrodes.

This means an improvement on the team’s previous carbon electrodes, which were able to reach 70 percent void space.

The scientists now believe that the best route for increasing energy density is tuning the carbon structure. And this has meant that it is possible to produce an electrode which can store four times as much energy compared to current lithium ion batteries.

They also believe that orderly structure of the carbon carpets means that they are easily observed, offering hope for further improvements.

However the team has noted that it will still be necessary to take these developments from the lab and into a commercial product.