Because of the screen printing.
After the solar cell has undergone processes such as texturing, diffusion and PECVD, it has been transformed into a PN junction, which can generate current under light. In order to conduct the generated current, this is necessary. to make positive and negative junctions on the surface of the battery electrode. There are many ways to manufacture electrodes, and screen printing is currently the most common production process for manufacturing solar cell electrodes.
For solar cells, in order to obtain the highest possible photoelectric conversion efficiency, the cell structure must be designed in detail. The metal grid is responsible for guiding the photocurrent inside the battery to the outside of the battery. Optimal design of solar cell arrays relies on minimizing total battery power loss.
A well-designed grid structure will minimize the series resistance of the battery, thereby minimizing power loss and maximizing power output. This is especially important for single solar cells with large area power output.
Reducing the width of the fine grid lines during the process can reduce the required optimal spacing of the fine grid lines, which can significantly reduce the total relative power loss of the side current of the upper layer and the relative power of the fine lines. shading losses of the grid line, thereby reducing the total power loss caused by the electrode. In order to increase the resistance of the sheet and reduce the power loss caused by the electrode, it is necessary to increase the number of fine grid lines and reduce the width of the fine grid lines.
Detailed information
Screen printingie uses printing to print predetermined graphics on the substrate. The gear is printed with silver foil paste on the back of the battery. , consisting of three parts: aluminum paste printing on the back of the battery and silver paste printing on the front of the battery. Its working principle is as follows:
Use the mesh of the sieve pattern to penetrate the slurry, apply some pressure to the slurry sieve part with a scraper, and move to the other end of the sieve at the end. at the same time. The ink is expelled by the scraper from the mesh of the graphic part onto the substrate during movement. Due to the viscosity of the paste, the impression is fixed within a certain range. When printing, the scraper is always in linear contact with the screen printing plate and the substrate. The contact line moves with the movement of the scraper, completing the movement. blow ofimpression.
Baidu Encyclopedia-Solar Cells