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The safety issues and lower energy density of the lithium metal batteries are the two main challenges that hinder their applications in the fields of electric vehicles and portable devices. In this work, the semi-interpenetrated polyvinylidene fluoride-hexafluoropropylene (PVdF-HFP)-based gel polymer electrolyte was synthesized through UV-curing method by employing the ethoxylated trimethylolpropane triacrylate (ETPTA) monomer. The semi-interpenetrating networks formed by polymerization of ETPTA and the high liquid absorption rate of the PVdF-HFP impart the as-prepared electrolyte with a high room temperature ionic conductivity of 3.17 × 10−3 s cm−1 and a high mechanical strength of 3.46 MPa. LiFePO4 was selected as cathode materials, and the active material loading of the cathode is about 4.2 mg cm−2. The electrolyte shows superior long-term cycling properties (127 mAh g−1 after 200 cycles at 0.5 C), excellent rate performance (113 mAh g−1 at 1 C, 80 mAh g−1 at 2 C, and the discharge capacity of 135 mAh g−1 can be restored when the rate goes back to 0.1 C) as well as good ability to inhibit the growth of lithium dendrite (about 150 h). The facile synthesis strategy and great electrochemical performance of the electrolyte make it a potential candidate for lithium metal batteries.

CO2-based mixture is a potential working fluid choice of combined cooling and power cycle (CCP) due to its superior thermodynamic performances and the removal of the limit of CO2 critical temperature. This study proposes a CCP system using CO2-based mixtures, loaded on a refrigerated truck, to realize multi-mode transformations for diverse cooling and power demands. The components of mixtures are strictly screened and key parameter analyses and optimization in terms of energy, exergy, adjustability, and economic performance are conducted to find the general laws and the best composition of the mixtures. The results show CO2-based mixtures have better energy-saving potential, adaptability, adjustability, and compactness than CO2. By comparison, CO2/R32 is recommended for superior output capacity, lower operation parameters, remarkable adjustability, and cheaper investment cost. CCP using CO2/R32 can maximally achieve 6.9% power enhancement or 5.9 times cooling enhancement relative to the refrigerated truck using a stand-alone refrigerator, and 19% power increase or 80% cooling increase relative to the CO2 system. It can realize smooth and steady mode transformation to achieve complex and diverse allocation of refrigeration and power in actual operation.