At present, the market of electrochromic technology is quite extensive. Most of the electrochromic glass windows are made by applying translucent indium tin or fluoride tin oxide film to two pieces of glass to obtain electrical conductivity, and then apply electrochromic tungsten oxide to one of the glass, and then glue two pieces of glass together with a kind of glue like electrolyte.
Electrochromic materials are divided into inorganic materials and organic materials. Inorganic materials can be divided into metal oxides and covalent metal complexes. The representative material of metal oxide is tungsten trioxide (WO3). The principle of discoloration is mainly that the energy of the inorganic material falls within the energy range of the visible light region, so when the valence of metal oxide changes, it can just cover the visible light area, reflect the color we see in the naked eye, and some special tungsten oxide derivatives. The compounds even possess bipolar characteristics of redox. In addition to tungsten oxide, the common covalent metal malocclusion is Prussian blue (Prussian Blue), and its principle is that absorption energy under different valence changes the absorption spectrum of the material itself.
The hidden function of tungsten oxide is expected to be applied in the field of new energy batteries. Recently, a high capacity and fast charge electrochromic battery has been developed. The battery is positive and negative with tungsten oxide (W18O49) nanowires and metal aluminum. It can establish an interface with users to identify the capacity by color change. When the state is transparent, the quantity of electricity is full, and the color gradually turns blue to mark the consumption of storage electricity, and the electricity is exhausted when the color is the deepest. The pool can be quickly charged by adding a trace of hydrogen peroxide, or using an external power supply to recharge and use the oxygen in the air to self - charge. The battery is more than 6 times as high as the same battery. This technology can change and improve the details and quality of life around us.
Electrochromic battery is a new type of battery which combines battery technology and electrochromic technology. It has unique color change characteristics. It can show the capacity of battery by the difference of its own color. A kind of interface is established between the user and the battery. However, electrochromic cells are facing many challenges at the present stage, and their capacity, charging time and cyclic stability are not ideal, but there is no doubt that electrochromic cells have an unlimited market potential.