Register Hardware

Original URL: http://www.reghardware.co.uk/2007/08/22/battery_design_flaw/

Li-Ion battery design 'flawed'

By James Sherwood
Published Wednesday 22nd August 2007 13:16 GMT

It won't come as much of a surprise to Sony, but the present design of lithium-ion cell batteries that power our consumer electronics is flawed, according to Japanese researchers. The startling announcement has been made by the Tokyo Institute of Technology, which claims that such batteries must be redesigned to avoid further potential dangers.

A spokesperson at the institute has described (http://business.timesonline.co.uk/tol/business/industry_sectors/technology/article2295743.ece) the average lithium-ion battery as “quite a dangerous little box of energy” and said changes must be made to the way batteries are developed, in order to make them safer and robust enough for our everyday gadget needs. For example, it has been claimed that encasing a battery’s electrodes in a solid polymer electrolyte, rather than submerging them in an organic solvent, could be safer.

The Institute’s claims are supported by evidence from a spokesman at the National Institute of Advanced Industrial Science and Technology, who says that companies are “less cautious about designing batteries with a focus on safety”.

Some manufacturers would be wise to sit-up and take note, as there have been dozens of reports of potentially dangerous batteries over the last few months. For example, thousands of Sony batteries have already been recalled (http://www.reghardware.co.uk/2007/08/10/sony_toshiba/) over safety fears and earlier this month it was announced that some 46m Nokia handset batteries could be dodgy (http://www.reghardware.co.uk/2007/08/14/nokia_overheating_battery/).

An alternative design was recently unveiled by researchers in the US, who developed a flexible paper battery (http://www.reghardware.co.uk/2007/08/14/paper_batteries/) that can pump out around 2.5 volts, enough power to illuminate a small light.