Experimental and simulation study on hygroscopic hydrogel-based thermal management of electronic device

Abstract

With the increasing power of electronic devices, thermal management has become crucial for their operational efficiency and lifespan. In this work, we have demonstrated a sorption-based thermal management strategy enabled by hygroscopic hydrogel. The polyacrylamide (PAM) hydrogel impregnated with LiCl (PAM-LiCl) was attached to a silicon wafer. And Pt metal circuits were coated to the silicon wafer to measure the temperature variations under different heat flux densities. The results show that the hydrogel can effectively reduce the surface temperature. At a heating power of 0.3 W/cm2, the temperature control duration reached 30 min, with an average effective heat transfer coefficient of 65.5 W/(m2·K) and an effective heat storage density of 171 J/cm2. Additionally, we developed and validated a multiphysics model considering desorption and vapor diffusion within the hydrogel. Numerical results indicate that during the desorption cooling process, the surface heat transfer resistance and the internal diffusion resistance play a dominant role. Additionally, we analyzed the effects of material properties, structure parameters, and operating conditions on the thermal management performance. This study helps to understand the key points of sorption-based thermal management technology and guide the design and optimization of sorption-based thermal management system.