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12Passive thermal management systems using phase change materials (PCMs) 13 provides an effective solution to the overheating of lithium ion batteries. But this 14 study shows heat accumulation in PCMs caused by the inefficient cooling of air 15 natural convection leads to thermal management system failures: The temperature in a 16 battery pack operating continuously outranges the safety limit of 60 o C after two 17 cycles with discharge rate of 1.5C and 2 C. Here a hybrid system that integrates 18PCMs with forced air convection is presented. This combined system successfully 19 prevents heat accumulation and maintains the maximum temperature under 50 o C in 20 all cycles, even with 7 o C rise in the ambient temperature. Study on airspeed effects 21 reveals that thermo-physical properties of PCMs dictate the maximum temperature 22Recently, passive thermal management system using phase change materials 47

High-efficiency visible-light-driven Ag 3 PO 4 /AgI photocatalysts with different mole fractions of AgI have been synthesized via an in-situ anion-exchange method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energydispersive spectroscopy (EDS), and UV−vis diffuse reflectance spectroscopy (DRS). Under visible light (>420 nm), the Ag 3 PO 4 /AgI photocatalysts exhibit enhanced photocatalytic activity compared to pure Ag 3 PO 4 or AgI for the degradation of methyl orange and phenol, and the highest activity is reached by the Ag 3 PO 4 /AgI hybrid photocatalyst with 20% of AgI. The quenching effects of different scavengers suggest that the reactive h + and O 2•− play the major role in the MO degradation. Detailed X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) analysis reveals that Ag nanoparticles (NPs) form on the surface of Ag 3 PO 4 /AgI in the early stage of the photocatalytic oxidation process, thus leading to the transformation from Ag 3 PO 4 / AgI to Ag 3 PO 4 /AgI@Ag. The excellent photocatalytic activity of the Ag 3 PO 4 /AgI photocatalysts can be ascribed to the efficient separation of photogenerated electron−hole pairs through a Z-scheme system composed of Ag 3 PO 4 , Ag, and AgI, in which the Ag nanoparticles acted as the charge transmission bridge. The Ag 3 PO 4 /AgI hybrid remains good photocatalytic activity after five cycling runs.

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