Advanced Nickel Oxide Based Materials for Electrochromic Applications
The optical transmission and/or optical reflectivity of electrochromic coatings can be varied repeatedly and reversibly between low and high transmission states, and/or between low and high reflectivity, by applying an electrical potential between the top surface and bottom surface of the electrochromic coating. In the specialized application to architectural windows, or windows comprising the exterior envelopes of buildings, electrochromic coatings on the window glass can be used to control the amount of sunlight and/or solar heat that enters the building. This control can extend from ultraviolet wavelengths into the infrared, to modulate the entire solar spectrum of sunlight that typically reaches habitable buildings.
Nickel oxide counter electrodes do not exhibit rapid switching kinetics in Li-ion electrolytes. In addition, the switching kinetics in nickel oxide counter electrodes deteriorate rapidly as the film thickness increases. Scientists at the National Renewable Energy Laboratory (NREL) have developed a method which improves the switching kinetics of electrochromic counter electrodes through well-defined control of the material composition. The remarkable improvement in switching kinetics enables the use of thicker films in electrochromic devices, thus allowing for further improvements in optical modulation and charge capacity within the electrochromic device. Most importantly, little or no perceptible tinting remains when the counter electrodes are in their bleached state.
· Improved visual performance
· Increased switching kinetics
· Increased device efficiency and durability
· Improved energy and cost savings
· Allows for the use of thicker films
· Improved optical modulation
· Improved charge capacity
Applications and Industries
· Electrochromic films
· Energy efficient buildings
· Smart windows
· Dynamic glazing technologies
Patents and Patent Applications
|Title and Abstract||
Ternary nickel oxide materials for electrochromic devices
Compounds having the formula Li.sub.aEC.sub.1M1.sub.bM2.sub.cO.sub.x, wherein "a" ranges from about 0.5 to about 3; b+c ranges from about 0.1 to about 1; c/(b+c) ranges from about 0.1 to about 0.9; and wherein x is about 0.1 to about 50, are disclosed. Methods of making these compounds as well as their use in thin film materials and electrochromic devices are also disclosed.
|National Renewable Energy Laboratory||03/31/2015
|Technology ID||Development Stage||Availability||Published||Last Updated|
|NREL ROI 12-64||Production||Available||12/16/2015||12/16/2015|