Power and Signal Distribution and Supplies in Stretchable Electronics
Sprache des Vortragstitels:
2010 MRS Spring Meeting, San Francisco, USA
Sprache des Tagungstitel:
Martin Kaltenbrunner, Gerald Kettlgruber, Christian Siket, Reinhard Schwoediauer and Siegfried Bauer.
Stretchable electronics is building or embedding electronic circuits and devices in a stretchable material. Substrate and interconnects must be made stretchable rather than flexible or rigid, like in flexible electronics or printed circuit boards. In stretchable electronics, sparse research has been devoted to embedded power supplies and signal distribution. Here we present concepts for ultra-compliant and mechanically robust batteries for delivering power to stretchable electronics, as well as stretchable optical interconnects for power transmission and signal distribution. The compliant battery is based on the acrylic VHB elastomer from 3M. Electrodes are based on a carbon black - silicon oil gel. Chemically active materials are Zn and MnO2, the basics of zinc carbon batteries. Active areas of approximately 1cm2 are prepared with a lateral separation of 0.3cm, to avoid intermixing of the chemicals upon stretching. The two active electrodes are closed with a Xanthan electrolyte gel. Open circuit voltages of 1.47V and short circuit currents of up to 40mA have been achieved, with a capacity of 3mAh/cm2 active cell area. The loss in open circuit voltage of the batteries is comparable to that of zinc carbon elements. Such batteries can easily be connected in series to enhance voltage or parallel to enhance current. Stretching up to 50% is demonstrated with a serial connection of two elements, driving an embedded light emitting diode. Power and signal distribution is also feasible by means of stretchable optical interconnects. First attempts towards stretchable multimode optical waveguides, directly coupled with laser and photodiodes for light generation and detection are introduced, providing alternative means to standard electrical wiring for interconnecting stretchable electronic devices. Acknowledgment: Work partially supported by the Austrian Science Funds.