Originally Published MDDI November 2002
R&D DIGEST
Harvesting the Power of Body HeatA microcontroller, water-resistant packaging, and conductive fabrics are the basis for wearable electronics that can be used in such products as watches and MP3 players. Combined with a novel power system that uses body heat to generate electricity, however, the technology may have new applications that include medical sensors and hearing aids.
Infineon Technologies AG (Munich) originally developed its small silicon "energy harvester" to power sensors in automobiles. The firm's Laboratory for Emerging Technologies is now adapting the thermal generating technology to other applications, including medical uses.
The technology is based on application of the Seebeck effect, in which the temperature gradient between the two sides of a Peltier junction generates an electrical current across the junction. Researchers at Infineon believe that a silicon-based thermocouple would provide an inexpensive yet safe method of powering various types of devices.
The firm has developed a package and interconnect system that can be linked to conductive threads woven into fabric. In addition to providing a power source for hearing aids, in which heat from ear tissue would be harnessed, the system could also power wireless data transmitters connected to cardiac monitoring equipment.
Infineon believes that a thermal generator capable of powering a hearing aid is feasible, and that it would prove more cost-effective than replaceable batteries. A prototype of the chip is expected to be available by the end of the year.
Copyright ©2002 Medical Device & Diagnostic Industry
