The present disclosure includes an effective optical region within a transmittance variable region, and sets the transmittance variable region and the effective optical region so that a shortest distances from a periphery of the transmittance variable region to a periphery of the effective optical region, d1 and d2, are 7.5% or more and 25% or less of a length of the transmittance variable region on a straight line including the shortest distances, L1, in a vertical direction.

An apparatus can include an electrochromic device. When using the apparatus, the electrochromic device can be switched from a first transmission state to a continuously graded state and maintained at continuously graded transmission state. An apparatus can include an active stack with a first transparent conductive layer, a second transparent conductive layer, an anodic electrochemical layer between the first and the second transparent conductive layers, and a cathodic electrochemical layer between the first and the second transparent conductive layers. The apparatus can further include a first bus bar electrically coupled to the first transparent conductive layer, a second bus bar electrically coupled to the second transparent conductive layer, where the second bus bar is generally non-parallel to the first bus bar, and a third bus bar electrically coupled to the first transparent conductive layer, where the third bus bar is generally parallel to the first bus bar.

An electro-optic element includes a first substrate defining first and second surfaces and a second substrate defining third and fourth surfaces. A first electrically conductive layer is disposed on the second surface and a second electrically conductive layer is disposed on the third surface. An electrochromic medium is disposed in a cavity between the first and second substrates, the electrochromic medium including an anodic component and a cathodic component. At least the anodic component is configured to reversibly attenuate transmittance of light having a wavelength within a predetermined wavelength range when in an electrochemically activated state. The anodic component includes a substituted ketal phenazine compound.

In an electrochromic element including a pair of electrodes and an electrochromic layer disposed between the pair of electrodes, a shape of a light modulating region viewed from a normal direction of the electrode being circular, when a sheet resistance of the electrode is r.sub.s (Ω), a resistance of the electrode is r (Ω), a diameter of the light modulating region is L [m], a distance between the pair of electrodes is d (m), the resistivity of the electrochromic layer is ρ (Ω), and a resistance of the electrochromic layer is R (Ω), a resistance ratio (r/R) between the electrode and the electrochromic layer, as shown by r/R=(r.sub.sL.sup.2)/(ρd), is 2 or more and 20 or less.

An electrochromic device includes a charge balancing thin film comprised of a new vanadium oxide with a formula of VO.sub.x, which provides a high charge density, low coloration efficiency, an electroactive voltage in close proximity to those of some electrochromic materials, and high chemical and electrochromic stability. Vanadium oxide can be without doping or doped with others. The VO.sub.x charge balancing thin film has a porous nanostructure and is amorphous or a combination of amorphous and polycrystalline, and can work with electrochromic conjugated polymer in the device in a minimally color changing mode. A method to design a material for a charge balancing thin film to pair with a working electrode and obtain a low device voltage in an electrochromic device is disclosed. Methods to prepare related charge balancing thin films are also disclosed.

Various embodiments herein relate to electrochromic devices and electrochromic device precursors, as well as methods and apparatus for fabricating such electrochromic devices and electrochromic device precursors. In certain embodiments, the electrochromic device or precursor may include one or more particular materials such as a particular electrochromic material and/or a particular counter electrode material. In various implementations, the electrochromic material includes tungsten titanium molybdenum oxide. In these or other implementation, the counter electrode material may include nickel tungsten oxide, nickel tungsten tantalum oxide, nickel tungsten niobium oxide, nickel tungsten tin oxide, or another material.

An electro-optic element includes a first substrate defining first and second surfaces and a second substrate defining third and fourth surfaces. A first electrically conductive layer is disposed on the second surface and a second electrically conductive layer is disposed on the third surface. An electrochromic medium is disposed in a cavity between the first and second substrates, the electrochromic medium including an anodic component and a cathodic component. At least the anodic component is configured to reversibly attenuate transmittance of light having a wavelength within a predetermined wavelength range when in an electrochemically activated state. The anodic component includes a substituted ketal phenazine compound.

The electrochromic device includes a first substantially transparent substrate coupled to a first transparent electrode, a second substrate coupled to a second electrode, and an electrochromic medium. The electrochromic medium includes at least one solvent and/or an electrolyte gel, at least one cathodic material, and at least one anodic material. The cathodic material can be a cathodic organic framework electroactive material and/or the anodic material can be an anodic organic framework electroactive material. At least one of the anodic and cathodic organic framework electroactive materials is electrochromic.

An electrochromic display element is provided. The electrochromic display element includes a pair of electrodes and an electrochromic layer disposed between the electrodes. The electrochromic layer contains a solvent, a supporting electrolyte, an anodic electrochromic molecule comprising a triarylamine derivative, and a cathodic electrochromic molecule comprising a viologen derivative. Concentrations of the triarylamine derivative and the viologen derivative in the electrochromic layer are each 4 mM or more.

Conventional electrochromic devices frequently suffer from poor reliability and poor performance. Improvements are made using entirely solid and inorganic materials. Electrochromic devices are fabricated by forming an ion conducting electronically-insulating interfacial region that serves as an IC layer. In some methods, the interfacial region is formed after formation of an electrochromic and a counter electrode layer. The interfacial region contains an ion conducting electronically-insulating material along with components of the electrochromic and/or the counter electrode layer. Materials and microstructure of the electrochromic devices provide improvements in performance and reliability over conventional devices.