The new battery includes a heat-resistive insulator inside the battery cell, next to an existing separator that insulates the anode and cathode. If that separator is punctured a short circuit occurs that typically causes the battery to overheat and in some circumstances catch fire. Panasonic said its insulation layer ensures that the battery won't overheat even in the event of a short circuit.

Panasonic's announcement responds to consumers' concern about the safety of lithium-ion batteries following a number of incidents involving them.