Electrochromic device with improved cycling stability
AssigneeAmbilight Inc.
InventorsXuefei Li, Jianguo Mei
Life of this patent
Estimating the term…
Abstract
An electrochromic device incorporating a high-energy absorbing polymer is presented to have an improved cycling stability. Various types of stable electrochromic devices are presented, including a highly stable yellow electrochromic device. Methods to improve the device cycling stability are also presented.
Claims9
An electrochromic device, comprising an electrochromic layer, wherein:
- the electrochromic layer comprises an electrochromic polymer having an absorbance peak within 350-500 nm or having a maximal absorbance within 350-500 nm that is at least 50% of a maximal absorbance within 400-750 nm;
- and
- the electrochromic layer is configured to work under an effective overpotential of less than 1V, wherein the effective overpotential is ηeff=Eox−Eoc, where Eox is an oxidation onset potential and Eoc is an open circuit potential;
- such that the electrochromic device maintains more than 95% optical contrast after more than 500 cycles.
An electrochromic device, comprising an electrochromic layer, wherein:
- the electrochromic layer comprises an electrochromic polymer having a polyfluorene structure;
- and
- the electrochromic layer is configured to work under an effective overpotential of less than 1V such that the electrochromic device maintains at least 50% optical contrast after more than 100 cycles,
- wherein the effective overpotential is ηeff=Eox−Eoc, where Eox is an oxidation onset potential and Eoc is an open circuit potential.
A method for improving cycling stability of an electrochromic device that comprises an electrochromic layer, the method comprises limiting an effective overpotential for the electrochromic layer to work under 1V, wherein the effective overpotential is ηeff=Eox−Eoc, where Eox is an oxidation onset potential and Eoc is an open circuit potential.
Dependencies are inferred from the claim text.