Experimental Investigation of Thin PCM Packages and Thermal Spreader for Thermal Management of Portable Electronic Devices

As the size of portable electronic devices, like tablet computers or smartphones, continues to decrease and their performance continues to increase, thermal management of the generated heat is becoming an ever more important issue. Phase change materials (PCMs) integration is a promising approach to reduce overheating of electronic components in tablet design while keeping the temperature of the cover surface within a comfortable range. This work focuses on the experimental thermal investigation of thin encapsulated PCM packages in combination with a thermal spreader as a solution for thermal management in portable electronic devices. The packages had an overall thickness of less than 2 mm in order to meet the requirements for integration in thin portable electronic devices. A simplified setup at a scale similar to a modern tablet computer was used for the experimental investigations. Experiments were conducted to study, for the first time, the local thermal behavior of the thin packages and their influence on the temperature increase of the heat source and cover surface. Two different PCMs were tested: n-eicosane and dodecanoic acid. An aluminum sheet with a thickness of 0.4 mm was used as a thermal spreader. It was determined that the combination of a spreader and the thin PCM packages led to substantial reduction of the temperature increase of both the heater and the cover. Compared to the case where neither a spreader nor a PCM package was used, the heater and cover maximum temperatures were reduced by 45% and 42%, respectively, when a constant heat power input of 5 W for 60 min was applied.