Robust energy storage device powers smart cards

TDK has released the EDLC041720-050-2F-13, an ultra-thin, high-energy capacitor suitable for powering devices such as electronic paper displays in smart cards.

With a volume of 27 x 17 x 0.45mm, the capacitor can be mounted inside a smart card or other thin device. When fully charged, it is claimed to provide around 50mJ of energy to power a load. The fast-charging characteristics of the EDLC041720-050-2F-13 make it compatible with radio-frequency energy harvesting circuits. Tests show that its 5mF capacitance can be charged in less than 1s by the field emitted by a standard NFC reader.

The device’s 5mF capacitance is also claimed to provide sufficient energy to power advanced biometric forms of authentication. While RF energy harvesting is suitable for many smart and contactless payment card applications, the capacitor may in addition be charged by other forms of harvested energy, such as that generated by film solar cells.

Despite being about one fifth as thick as TDK’s previous generation of EDLCs, the EDLC041720-050-2F-13 is said to be resistant to damage by twisting and bending, and offers a long operating lifetime. It is rated for operation over a temperature range of -20 to 60°C, and is also claimed to be resistant to electro-static discharges and pressure.