Panasonic has been working on a new approach to the design and production of litium-ion batteries that seems to have solved the pesky problem of having them burst into flames from time to time.
The battery is protected from overheating by the addition of a heat-resistant insulator to the battery cell. Normally, a li-ion battery would only have a thin separator between the cathode and the anode that could easily be punctured by a short-circuit. And as we are now painfully aware, short-circuiting batteries can sometimes lead to bad things such as fires and explosions. The additional heat insulator, according to Matsushita, has better insulating and protective features than the current separator and will prevent overheating even in the event of a short-circuit.