A major breakthrough in perovskite-silicon tandem solar cell research, led by Tongwei’s PV Technology Center, has been achieved. The newly developed cell structure demonstrated a conversion efficiency of 31.4%, certified by both the National Institute of Measurement and Testing Technology (NIMTT) and the Fujian Institute of Metrology (FJIM). This result significantly outperforms the control group using traditional annealing processes, which recorded an efficiency of 29.43%. The achievement not only sets a new industry record but also marks a critical step forward in the industrialization of next-generation high-efficiency photovoltaic cell technology in China.
The cell employs a wide-bandgap perovskite (1.73 eV) as the top cell and pairs it with a fully textured silicon heterojunction (SHJ) bottom cell to form a two-terminal tandem device. A key highlight is the team’s development of a low-temperature preparation method termed “sequential annealing.” Under standard ambient conditions, this process precisely controls annealing temperature and time phases, significantly improving the coverage and crystalline quality of perovskite films on textured silicon surfaces. It enables low-defect, highly uniform conformal growth, thereby enhancing both cell performance and stability. According to corresponding author Yuchao Hu, the entire process is conducted at low temperatures (100–150°C), takes no more than half an hour, and exhibits strong compatibility with existing heterojunction production lines, indicating clear potential for industrial application.
