Cutting edge batteries recharge in seconds

Breakthrough battery can charge up in seconds

The days of waiting hours to charge a mobile phone or laptop computer could soon be over because of research that could transform battery technology in as little as two years.

Scientists in the United States have invented a battery that can charge in seconds, promising a revolution in power storage that could also help green cars and renewable energy.

The advance allows lithium-ion batteries, the standard variety used in consumer electronics and cells for electric or hybrid vehicles, both to charge and discharge stored energy more quickly than at present.

This should lead to smaller, lighter batteries for mobile phones and other devices, which can be fully charged when plugged in for a few seconds.

The researchers, from the Massachusetts Institute of Technology, have already made a small prototype cell that charges fully in 10 to 20 seconds, compared with six minutes for cells made in the standard way.

“If you can charge your phone in 30 seconds, that becomes a life changer,” said Gerbrand Ceder, Professor of Materials Science and Engineering at the Massachusetts Institute of Technology (MIT), who led the research. “It could change the way we think about technology like this: you would literally be able to charge up while you stand and wait.”

The technology has been nicknamed the “beltway battery”, after the orbital motorway in Washington DC, because it uses a bypass system to let lithium ions that carry charge to enter and leave the battery more quickly.

As it involves a new approach to manufacturing lithium-ion battery materials, rather than a new material, it could be ready within two to three years, the researchers said.

Electric car batteries may be able to charge in less than an hour, removing one of the main barriers to wider uptake of the vehicles. Solar and wind power generation could also benefit as better batteries could be used to store surplus energy.

Rechargeable batteries store and release energy as charged atoms, called ions, from between two electrodes called the anode and the cathode. Their charge and discharge rates are limited by the speed with which these ions move.

Professor Ceder and Byoungwoo Kang, his colleague, established that ions can move quickly across the lithium iron phosphate that is used as the cathode in lithium-ion batteries. However, the ions are effectively held up because they must find their way through channels in the material.

“It is like a freeway, but if the ramps are congested you can't get on to it very fast,” Professor Ceder said.

The scientists found that by coating particles of lithium iron phosphate in a glassy material called lithium pyrophosphate, ions can bypass these channels and move more quickly. “It works like a beltway around a city,” Professor Ceder said.

(http://technology.timesonline.co.uk/tol/news/tech_and_web/article5891194.ece)