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Herein, the thermally conductive composite polymer membranes (CPMs) with silica-coated silver nanowires (AgNWs@SiO2) and poly­(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) are first fabricated by an electrospinning technique. Various composite gel polymer electrolytes (CGPEs) are investigated with different weight percentages of AgNWs@SiO2 with respect to PVDF-HFP in the presence of liquid electrolytes. The CPMs display high thermal conductivity and thermal stability, good mechanical strength, and high electrolyte uptake. The thermal conduction property of CPMs was analyzed by a bidirectional asymmetric heat transfer model. Moreover, the CGPEs with the electrospun CPM as the matrix and AgNWs@SiO2 as fillers (es-CGPEs) possess the high ionic conductivity and excellent electrochemical performance compared to the Celgard separator system. The Li/es-CGPEs/LiFePO4 cell shows an enlarged excellent cycling life and better rate performance at 25 and 60 °C, in comparison to the one without AgNWs@SiO2 fillers. Interestingly, the Li/es-CGPEs/LiFePO4 cell in the presence of 5 wt % of AgNWs@SiO2 still delivers an excellent rate capability at 0 °C. The es-CGPE with AgNWs@SiO2 would be a promising candidate as the electrolyte material toward wide temperature lithium metal batteries.

Silicon Carbide (SiC) is a typical material for third-generation semiconductor. The thermal boundary resistance (TBR) of 4H-SiC/SiO2 interface, was investigated by both experimental measurements and theoretical calculations. The structure of 4H-SiC/SiO2 was characterized by using transmission electron microscopy and X-ray diffraction. The TBR is measured as 8.11×10 -8 m 2 K/W by 3ω method.Furthermore, the diffuse mismatch model was employed to predict the TBR of different interfaces which is in good agreement with measurements. Heat transport behavior based on phonon scattering perspective was also discussed to understand the variations of TBR across different interfaces. Besides, the intrinsic thermal conductivity of SiO2 thin films (200~1,500 nm in thickness) on 4H-SiC substrates was measured by 3ω procedure, as 1.42 W/m·K at room temperature. It is believed the presented results could provide useful insights on the thermal management and heat dissipation for SiC devices.

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