Polyvinyl Butyral\nSolid Electrolyte Film and Its Electrochromic\nLaminated Safety Glass

In recent years, the application of electrochromic laminated\nsafety\nglass has attracted more and more attention, relying on polyvinyl\nbutyral (PVB) solid electrolyte film. Herein, the ionic conductivity\n(σ) of the PVB film has been improved by a cross-linked structure\nand blended with LiClO<sub>4</sub>, which can reach as high as 1.78\n× 10<sup>–4</sup> S cm<sup>–1</sup> at room temperature.\nIn addition, their excellent comprehensive characteristics have been\nconfirmed, such as mechanical strength, high visible light transmittance\n(>90%), high bond strength (4.2 MPa), and excellent thermal stability.\nBased on the PVB film above, WO<sub>3</sub>-laminated electrochromic\ndevices with 5 × 5 cm<sup>2</sup> and 10 × 10 cm<sup>2</sup> areas are constructed. They can remain stable after 20 000\ncycles monitored by cyclic voltammetry curves, indicating the PVB\nsolid polymer electrolyte (PSPE) with a cross-linked structure has\nthe potential commercial viability of large-area electrochromic devices\n(ECDs).