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Engineers at the University of Manchester are working with several industrial partners to develop a graphene / lithium-ion battery.
The work is part of a project exploring different ways to reduce the size and weight of batteries and extend their lifespan by adding graphene as a component material.
As well as companies such as Rolls-Royce, Sharp and Johnson Matthey, researchers are working with defence firm Qinetiq and Her Majesty's Government Communications Centre. The latter organisation is widely seen as the real-life version of Bond's "Q" and develops equipment for the Foreign Office, MI5 and MI6.
Research has already shown that lithium batteries with graphene in their electrodes have a greater capacity and lifespan than standard designs. Graphene is a potent conductor, extremely lightweight, chemically inert and flexible with a large surface area.
The £2 million project is also looking at graphene-based supercapacitors, which tend to have high power capability and longer cycle life than batteries, but lower energy storage capacity.
Professor Robert Dryfe, from the University of Manchester's School of Chemistry, is looking at how quickly electrons are transferred across graphene and the magnitude of capacitance – the amount of electrical energy that can be stored on graphene surfaces.
Professor Forsyth said that combining graphene batteries and supercapacitors could substantially increase the range of electric vehicles (EVs). Batteries for EVs usually weigh around 200kg – as much as three passengers. By reducing the weight of the batteries graphene could boost vehicle efficiency and increase the driving range of electric cars to beyond 100km – a limitation that currently prevents their widespread uptake.
Forsyth said: “If we can extend the distances that cars can travel between charge points we will instantly make them more popular. But how will the batteries cope with the real-life strains of driving? Electric cars – like all other vehicles – are not driven smoothly. Dramatic peaks in power demand as drivers accelerate will stress the battery and potentially limit its lifespan.”
The researchers will therefore test prototype graphene batteries and supercapacitors using real world stresses that mimic different driving profiles. “We can test the technology for driving in extreme weather conditions,” he said. “Many batteries struggle to perform in cold conditions, but our weather chamber will reveal any weaknesses.”
Graphene-based batteries could also be used in stationary energy storage systems. A grid-scale battery and converter system is being installed on Manchester’s campus to test large scale electrical storage. Researchers will use the battery system to develop methods to control the flow of electricity and reconcile differences between power generation and local demand.