Two years old but seems they know one reason why Li cells may catch fire...
BBC News - Cause of battery fire identified in Cambridge study
Cause of battery fire identified in Cambridge study
Scientists have identified a reason why lithium batteries in laptops and mobile phones may overheat and catch fire.
Cambridge University researchers said the growth of metal fibres, called dendrites, could cause short circuits.
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"Fire safety must be solved before we can get to the next generation of lithium-ion batteries and before we can safely use these batteries in a wider range of transport applications."