Biomimetic Passive Skin Cooling for High-End Handheld Devices

Increasing functionality demands more heat dissipation from the skin of handheld microelectronics devices. The maximum amount of heat that can be dissipated passively, prescribed by the natural convection and blackbody radiation theories, is becoming the bottleneck. In this paper, we propose a novel technique that may overcome this passive cooling limit. It is made possible by using a biomimetic skin capable of perspiration on demand. The key component of the biomimetic skin is a thin layer of temperature sensitive hydro gel (TSHG). The TSHG layer can sweat the skin with moisture when the skin temperature is higher than the TSHG’s lower critical solution temperature (LCST), and thus boost the heat dissipation rate through evaporation. The TSHG layer can be refilled by absorbing the moisture in air when the device batteries are being recharged. A generic practice of this novel cooling technique with preliminary analysis and experimental results is presented. With this novel passive cooling technology, a handheld device can be powered 2–4.8 times higher, and may be powerful enough to run a desktop operation system like a personal computer.Copyright © 2009 by ASME