Among all the hype about hydrogen engines, fuel cells, hybrids and electric cars powered by lithium ion batteries, a miniaturised version of an old mainstay has made news – a mini-motor than can run for two years on a squirt of lighter fuel!

Among all the hype about hydrogen engines, fuel cells, hybrids and electric cars powered by lithium ion batteries, a miniaturised version of an old mainstay has made news – a mini-motor than can run for two years on a squirt of lighter fuel!


The engine, which is tiny enough to power a watch and can be balanced on a fingertip, is said to produce 700 times more energy than a conventional battery despite being less than a centimetre long. Engineers at the University of Birmingham in the United Kingdom say it could be used to operate laptops and mobile phones for months on end - doing away with the need for recharging.


Dr Kyle Jiang, of the Department of Mechanical Engineering, said: "This is an enormous step forward. Devices which need re-charging or new batteries are a problem but in six years will be a thing of the past."


Other applications for the engine could include medical and military uses, such as running heart pacemakers or mini reconnaissance robots. At present, charging an ordinary battery to deliver one unit of energy involves putting 2 000 units into it.


A problem faced by engineers who have tried to produce micro motors in the past has been the levels of heat produced. The engines got so hot they burned themselves out and could not be re-used. The Birmingham team overcame this by using heat-resistant materials such as ceramic and silicon carbide.