Yongzhe Zhang

Solar Cells

College of Microelectronics, Faculty of Information Technology, Beijing University of Technology, Beijing, China

Email: yzzhang@bjut.edu.cn

Abstract for Presentation

High-efficiency silicon heterojunction solar cells

"Carbon peaking and carbon neutrality" is a major strategy in China at present. The utilization of renewable energy, mainly solar photovoltaic cells, is considered to be one of the core ways to achieve the current goal. It is predicted that by 2050, photovoltaic power generation will occupy the 39% of total electricity. Silicon-based photovoltaic cells account for more than 94% of the total photovoltaic market, and silicon heterojunction solar cells (SHJ cells) are considered to be one of the core alternative technologies for next-generation industrialized silicon-based photovoltaic cells.

The SHJ cell is a solar cell that can generate electricity from double-side by depositing intrinsic amorphous silicon and doped amorphous silicon on both sides of crystalline silicon in turn. The amorphous silicon film in its structure can passivate the crystal. On the other hand, the large band gap of the amorphous silicon film also promotes the remarkably high open circuit voltage and high photoelectric conversion efficiency of this type of cells (SHJ cell theory efficiency is 28.5%). However, there is still a large gap between the actual prepared SHJ cell efficiency and the theoretical limit efficiency, which affects its industrialization process. Finding the root cause that restricts the efficiency improvement of SHJ cells has become the core problem that needs to be solved urgently in the field. This report will report on the improvement of cell structure, optimization of crystalline silicon surface passivation, and research on heterojunction interface, focusing on the factors that affect the further improvement of cell performance at the current heterojunction interface, and make an outlook for further improvement of cell efficiency.