The new production process saves resources, increases the electricity yield and also has cost reduction potential. The process can also be applied to production processes beyond photovoltaics. The expertise of the HighLine Technology start-up is the result of a good ten years of research work on dispensing processes for the metallisation of silicon solar cells at the Fraunhofer Institute for Solar Energy Systems ISE. During this period, a multi-nozzle dispensing print head was developed and at the same time a great deal of know-how on printing pastes and processes was gained.
The dispenser technology can be easily integrated into conventional production lines for silicon solar cells, where it can replace the silk-screen printing normally used for applying the front metal contacts. The material consumption of cost-intensive silver is reduced by approx. 20%, the contacts become thinner and more semiconductor surface is available to sunlight, which results in an increase in the current yield and thus in the efficiency by approx. 1% relative to the original. The contactless process promises a lower reject rate when using thinner silicon wafers. In addition, the inline-compatible printing process will in future enable a significant increase in throughput compared to the screen-printing process commonly used in the industry. Other production steps in solar cell manufacture can also be optimised with the new process.
“Our main focus is currently on reducing material consumption in the photovoltaic industry,” says Dr. Maximilian Pospischil, Managing Director and one of the founders of HighLine Technology, adding: “We want to bring the highly efficient parallel dispensing technology developed at Fraunhofer ISE to the market. To this end, we will continue to work closely with Fraunhofer ISE PV-TEC. However, our dispensing technology is also interesting for other industrial production processes beyond the PV industry. We support companies from plant engineering to process integration and application”.
In the dispensing technology, the materials are pressed onto the surface of the solar cells in a contactless printing process through the finest openings of a highly parallel print head, similar to toothpaste through a tube opening. However, PV production developers use nozzle diameters that are only half as thick as a human hair (approx. 20 µm), with many nozzles working in parallel to produce the desired structures at high throughput.
HighLine Technology GmbH received funding from the EXIST research transfer programme of the German Federal Ministry of Economics BMWi and is also funded by the Fraunhofer Technologie-Transferfond Fonds GmbH – FTTF, among others.
The image (© Highline) shows HighLine’s parallel dispensing printhead for metallization of silicon solar cells
More information: https://highline-technology.com/