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Influence of separator wettability toward nonaqueous electrolyte was investigated in lithium-ion batteries using high-voltage LiNi 0.5 Mn 1.5 O 4 cathode. A fluorinated ether of 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (HFE) was introduced as a co-solvent into the control electrolyte and polyolefin separator wettability toward nonaqueous electrolyte was effectively enhanced. Even though conductivity of the electrolyte bulk decreased after HFE was introduced, ionic conductivity of the electrolyte-soaking separator increased due to the enhanced separator wettability. From cycling stability of the half cells using high-voltage LiNi 0.5 Mn 1.5 O 4 cathode, all electrolytes containing 10%, 20% and 30% HFE have superiority to the control electrolyte, and the 20% HFE containing electrolyte is the optimal. Microscopical analysis revealed that oxidative decomposition of HFE-containing electrolyte on the LiNi 0.5 Mn 1.5 O 4 cathode was suppressed effectively with the thinner cathode electrolyte interface than that in the control electrolyte. In Li 4 Ti 5 O 12 |LiNi 0.5 Mn 1.5 O 4 full cells, the 20% HFE containing electrolyte exhibited the enhanced cycling stability and rate capability compared to the control of 1 mol L −1 LiPF 6 /propylene carbonate. This work here reveals the effect of fluorinated ether co-solvent on separator wettability and further the superior separator wettability is critical to the oxidation stability of the electrolyte in lithium-ion batteries using high-voltage cathode.

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Colorization for fabricating aluminum pigments has broad application prospects in recent years. In this study, yellow-colored aluminum pigments with the double-layer structure Al@SiO2@PFMV were prepared using a sol-gel method. A crosslinked copolymeric dye (PFMV) was firstly synthesized by radical polymerization using vinyl triethoxysilane (VTES) and a small molecular dye (FGMAC) as monomers. Then, colored aluminum pigments were prepared by hydrolysis and condensation of the copolymers on the surface of aluminum pigments. SEM, AFM, FTIR, and XPS were used to characterize the surface morphology and chemical structure of the colored aluminum pigments. It was found that the colored aluminum pigments have a heterogeneous and smooth surface layer. The anticorrosion results showed that the colored aluminum pigments had better chemical stability with significantly improving corrosion resistance compared to raw aluminum pigments and Al@SiO2 with the single-layer coating. Chromatism analysis indicated that the lightness of Al@SiO2@PFMV pigments decreased slightly and the color changed from silver-gray to yellow.