NEC Develops Super Thin Battery For IC Cards
NEC recently announced the development of an ultra thin 0.3 mm organic radical battery (ORB) that is compatible with standard Integrated circuit (IC) cards (found on some credit cards, public transportation passes, and hotel keys).
Until now ORBs of 0.7mm thickness were standard, but this thickness is difficult to integrate into a plastic card that is only 0.76mm.
This new battery is superior in many ways and will offer new functionality that previous ORBs could not. The new ORB is more flexible, offers higher output and recharges faster. This could lead to cards that include an electronic display, antennae, or more advanced encryption technology.
The reduction in size was accomplished through new printing technologies that allow the battery to be printed directly on the card. A new polymer film of 0.05mm thickness was used, replacing the 0.2mm thickness aluminum laminate that is conventional for ORBs.
Prototypes are capable of 2,000 display screen updates, 360 consecutive flash firings and 35 location transmissions on a single charge. Furthermore, charge-discharge tests indicate that the batteries maintain 75% of their initial charge-discharge capacity after 500 cycles, equivalent to the performance of lithium-ion batteries for mobile phones.
Though the total power output is low at 3mAh capacity, the power density per volume is high at 5kW/L.
This technology could be used on IC credit cards to display the current balance directly on the card, or for security purposes to track where the card is without it physically being used. If they find a way to increase the power capacity, while maintaining the high power density per volume, the potential for this technology would be limitless.