Solar PV technology trends: Cell interconnection technologies
The solar industry is continuously evolving, and one of the recent trends in the industry is the advancement in module interconnection technology. Traditionally, solar cells were interconnected using zero-gap technologies, which involved aligning busbars over the cell’s fingers without any gap. However, new interconnection technologies are emerging to overcome the limitations of traditional methods and meet the industry’s growing demand.
The table below summarizes some of the recent interconnection technologies in the solar industry:
|Busbar||This traditional interconnection technology involves attaching busbars over a cell’s fingers with a conductive adhesive. It is simple and reliable but may reduce cell efficiency due to shading.|
|Multi-busbar||This technology increases the number of busbars from three to up to ten, reducing the distance between them and decreasing the shading effect. It also increases reliability and efficiency.|
|Shingled||In this technology, cells are cut into smaller pieces, overlapped, and interconnected without busbars, which reduces shading and increases efficiency. It also improves reliability by reducing mechanical stress.|
|Wire||This emerging technology replaces the busbars with thin wires that make contact with the cell’s fingers through mechanical pressure. It reduces shading and silver usage and increases efficiency and reliability.|
|Heterojunction with Intrinsic Thin Layer (HIT)||HIT technology uses transparent conductive layers instead of busbars to interconnect cells, reducing shading and improving efficiency. It also enhances cell reliability by minimizing localized mechanical stress.|
Drivers & Benefits: One of the primary drivers for the development of new interconnection technologies is the increasing cell size, which requires a larger number of interconnects to maintain efficiency. Additionally, the reduction in finger width and the increase in active cell area increase efficiency and reduce silver usage, thus lowering the cost of manufacturing. New interconnection technologies also improve redundancy and reliability by minimizing localized mechanical stress and ensuring that fractured cell fragments remain electrically connected.
Potential Risks: The introduction of new manufacturing processes and materials brings its own set of risks, including changes in geometry from rectangular ribbons to wires and material changes from metallurgical connections to mechanical contact. However, these risks can be mitigated through proper testing and validation before implementing the technology in large-scale production.
In conclusion, the solar industry is continually evolving, and new interconnection technologies are driving this change. These new technologies offer several benefits, including increased efficiency, reduced silver usage, and improved reliability. While there are potential risks associated with the implementation of new interconnection technologies, careful testing and validation can mitigate these risks.