Henan University researchers in China have developed a new self-powered electrochromic energy storage smart window prototype. The prototype combines kesterite (CZTSSe) thin-film solar cells with a nickel-cobalt bimetal oxide (NiCoO2) electrochromic window.
The prototype not only realizes the function integration of self-power and intelligent solar radiation adjustment but also extends its function to energy storage, the research’s lead author, Guofa Cai, told pv magazine.
The researchers constructed the solar cell using a glass base covered in molybdenum, a kesterite absorber, a cadmium sulfide buffer layer, a zinc oxide layer, an indium tin oxide layer applied through magnetron sputtering and silver metal connections. The researchers employed a straightforward chemical bath deposition approach to create the NiCoO2 electrochromic coatings intended for the window.
The window also features a titanium oxide counter electrode film, known for its high-performance electrochromic and energy storage capabilities. This film is an ion reservoir due to its effective charge performance and light transmittance.
During testing, the solar window demonstrated an energy usage of 318.3 mWh/m² and an overall efficiency of 2.15%. The researchers noted that these figures align with most solar windows created thus far; however, adding Kesterite means the prototype boasts a light-absorbing material that could be used for lower-cost thin-film solar cells.
The researchers detailed their work in the paper Multi-Functional Electrochromic Energy Storage Smart Window Powered by CZTSSe Solar Cell for Intelligent Managing Solar Radiation of Building.