Ultra-low-cost, flexible and durable electrochromic tape device based on aluminum foil. (1st February 2022)

• Record Type: Journal Article
• Authors: Rozman, Martin; Mavrič, Andraž; Kravanja, Gregor; Valant, Matjaž; Pakseresht, Amirhossein
• Is Part Of: Electrochimica acta. Volume 404(2022)
• Publication Date: 2022-02-01
• Subjects: Electrochromism -- Li-WO3 intercalation -- Flexible tape -- Aluminum electrode -- Low-cost; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2021.139760
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: Flexible electrochromic tape based on aluminum foil electrodes and "inverted sandwich" geometry. Good response time (5 s for tinting) with sharp contrast between bleached and tinted state. Ability to operate at high compression of 200 kg/cm 2 (19.6 MPa). 2 mm wide tape with 10 µm thick Al electrodes was able to endure force of up to 5.5 N and still operate normally. The device is constructed from "kitchen grade" aluminum, greatly reducing cost compared to traditional "sandwich geometry" devices that use conductive polymer or ceramics. Abstract: Electrochromic devices (ECDs) have the ability to selectively change their color state. They come in many forms, such as smart windows, e-ink displays and recently even as flexible tapes. Since most of ECDs incorporate traditional "sandwich" architecture, which requires at least one electrode to be made of a transparent conductive polymer or thin film ceramics, they are considered too expensive and fragile compared to devices made from metal or alloy foils. For the first time, we present a true low-cost, flexible and durable ECD tape that uses a common "kitchen-grade" aluminum foil for electrodes, while employing a Li-WO3 intercalation based electrochromic system. The presented ECD tape is capable of showing two color states. The tested tapes were up to 20 cm long but could be easily made longer due to their "inverted sandwich" architecture. Due to the absence of transparent counter electrode, the assembled ECD tape has excellent durability properties and could be used in color changing clothes, adaptive camouflage or other applications.