Solar PV technology trends: Trends in cell cutting technology
As solar technology continues to evolve, one trend that has emerged is the use of cell cutting technology to increase module efficiency. Cell cutting involves dividing solar cells into smaller pieces, or “half-cells,” to reduce resistive losses and improve shade tolerance.
The use of cell cutting technology offers several drivers and benefits, including:
- Reduces resistive losses: By dividing cells into half-cells, the electric current is reduced, which lowers resistive losses and increases efficiency.
- Potentially higher shade tolerance: By changing the junction box position and wiring pattern, cell cutting technology can improve the shade tolerance of solar modules.
However, there are also potential risks associated with cell cutting technology, including:
- Potentially increased cell fracture risk: Edge-defects can increase the risk of cell fracture, which is dependent on the cell cutting technologies and process control.
- Changed mechanical stress and strain field: The use of cell cutting technology can change the mechanical stress and strain field, which can potentially reduce cell deformation and decrease cell fracture risk.
- Orientation of half-cut cells: The orientation of half-cut cells can decrease fracture risk, with the fracture risk of the current industry standard being similar to that of full-size cells. By rotating the cells 90 degrees, the probability of fracture under static loading conditions can be reduced.
Over the last decade, there has been a significant increase in the use of cell cutting technology in the solar industry. According to a report by the National Renewable Energy Laboratory (NREL), the percentage of module production that used cell cutting technology increased from less than 1% in 2010 to over 60% in 2020.
The adoption of cell cutting technology has been driven by the desire to improve solar module efficiency, reduce costs, and increase shade tolerance. While there are potential risks associated with the use of cell cutting technology, ongoing research and development are working to mitigate these risks and ensure the continued growth and adoption of this technology.
| Cutting Technology | Potential Benefits |
|---|---|
| Mechanical scribing | Low cost, established process, suitable for large-scale production |
| Laser scribing | High precision, high throughput, versatile, can be used for various cell types |
| Reactive ion etching (RIE) | High precision, can produce narrower and deeper grooves, suitable for high-efficiency cells |
| Diamond wire sawing (DWS) | High throughput, low kerf loss, suitable for thinner wafers |
| Abrasive wire sawing (AWS) | High throughput, low cost, suitable for larger wafers |
| Stealth dicing | Low kerf loss, low damage to wafers, suitable for thin and fragile wafers |
The developments in cell cutting technologies over the last decade have led to significant improvements in the efficiency and cost-effectiveness of solar cell production. Mechanical scribing, which is an established process for producing grooves in silicon wafers, has remained a popular cutting technology due to its low cost and suitability for large-scale production.
However, laser scribing has emerged as a high-precision and versatile alternative to mechanical scribing, with the ability to be used for various cell types. Reactive ion etching (RIE) has also gained popularity due to its high precision, which allows for narrower and deeper grooves to be produced, making it suitable for high-efficiency cells.
Diamond wire sawing (DWS) has been developed as a high-throughput cutting technology with low kerf loss, making it suitable for thinner wafers. Abrasive wire sawing (AWS) has also gained traction due to its high throughput and low cost, making it suitable for larger wafers.
Finally, stealth dicing has been developed as a cutting technology that minimizes kerf loss and reduces damage to wafers, making it suitable for thin and fragile wafers. Overall, the advancements in cell cutting technologies have led to increased efficiency and cost-effectiveness in solar cell production.