The half-cut cell technology uses laser cutting to cut one cell into half in a direction perpendicular to the busbars, and then solders half cells in series. In order to conform to the electrical parameters of the modules consisting of entire cells, the series and parallel connection of the cells should be performed inside the modules. By cutting the entire cells into two halves, the original current is halved, resulting in lower resistance losses and higher performance. The resistance loss of the half-cut cell is reduced by 75%, and the power is increased by 3% compared to the entire cell.

Currently, half cell technology has become a standard configuration of high-efficiency modules. We all know that many advantages make the half-cell module outstanding, and the modules are easy to mass production. However, the research of this technology from Sunrise does not stop here. It has become a critical step to achieve differentiation by improved manufacturing processes.

PV modules are generally laminated with materials such as EVA, backsheet, glass and cells. From welding to product testing, packaging and storage, the interaction between the various processes is mutually constrained, and the quality of the modules will affect its outdoor life. We found that there may be following quality problems of modules in the actual production: cracking, bubbles, deformation of the appearance of module, the junction box burned, wherein bubbles may be the most common one for half-cell modules.

↑ (module delamination)

In the national standard crystalline silicon photovoltaic module requirements, continuous bubbles or delamination between the edges of the module and any parts of the circuit is considered a serious quality defect. When it is used outdoors, the bubbles will appear to be magnified due to the influence of light or normal operation of the module. In the long run, the EVA on the bubble position will be delaminated from the glass and the backsheet, and the water vapor will enter the module, and the performance and power will be affected, which eventually leads to module retirement.

↑ (bubbles at the edge of the bus bar of full-black module)

The half-cell module has become the mainstream in PV market today. In the lead-out position of the busbar of module, bubbles come out often. They can be seen with our naked eyes on the module with the black backsheet, but on the one with the white backsheet, they are difficult to find. Sunrise applies the "L" solution to its half-cell module, i.e., the welding method of the L-shaped bus bar drawn from the backsheet. This method can prevent the generation of bubbles at the edge of the bus bar, eliminate the hidden danger of delamination, and help to improve the safety of the power stations and increase the service life of the modules. To improve the appearance, Sunrise uses the spacers whose material same as the backsheet to shield the bus bar so that the overall appearance of module is harmonious.

It is the purpose for Sunrise to improve the quality of its products, and needs the support of mature processes and technologies to control the production.

At present, global energy is changing rapidly in the way of clean and low carbon, and the growth potential of PV industry will be further released. There is no doubt that the value of PV technology innovation will be even greater, and Sunrise’s high quality and efficiency PV products are promoting the energy revolution..