Longi achieves world record for highest tandem solar cell efficiency

Chinese solar module manufacturer LONGi recently announced that it has achieved a remarkable power conversion efficiency of 34.6% in its two-terminal tandem perovskite solar cell prototype devices.

The announcement was made during the publication of a scientific paper in the journal Nature, which details the perovskite-silicon tandem solar cell that was introduced last December. This newly achieved power conversion efficiency is currently the highest recorded for this type of cell.

The U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) confirmed the results, which constitute a world record for this cell typology. Previously, the record was held by Saudi Arabia’s King Abdullah University of Science and Technology (KAUST).

KAUST achieved 33.7% efficiency with a device with a similar configuration. Its cells were based on a double-layer interface passivation strategy, according to LONGi’s research team.

LONGi sets new efficiency standard

This dual-layer interface passivation strategy reportedly maximizes both electron transport and hole blocking. LONGi’s tandem team developed two-terminal prototype devices that were certified with record efficiency of 34.6%.

Although they did not provide further technical details, LONGi said, “Commercial-size two-terminal tandem cells “The world’s first square meter four-terminal tandem modules developed for mass production (M6) have been authorized with efficiencies of 30.1% and 25.8%, respectively. These results demonstrate a significant efficiency advantage over single-junction silicon cell technology.”

LONGi’s result was also reported as the first certified efficiency in a double-junction tandem solar cell to exceed the Shockley-Queisser limit of 33.7% for single-junction cells.

A long blog Emphasizing the company’s pragmatic and innovative research approach, the company has focused on generating independent certifications from leading institutions such as the US National Renewable Energy Laboratory (NREL), Germany’s Fraunhofer Institute for Solar Energy Systems (Fraunhofer ISE) and the European Solar Test Facilities (ESTI) over the years.

LONGi targets 43% efficiency as next milestone

According to the blog, the silicon-perovskite tandem solar cell is considered the mainstream technology for next-generation ultra-efficient solar cells solar cellsWith a theoretical maximum efficiency of up to 43%, it greatly exceeds the Shockley-Queisser limit of 33.7% for single-junction cells.

In November 2023, the LONGi tandem solar cell team achieved an efficiency of 33.9% for tandem cells, and less than a year later, it broke the record once again, demonstrating its strong R&D capabilities and relentless pursuit of discovery.

The team aimed to achieve significant breakthroughs by optimizing the deposition process of the electron transport layer film. They introduced high-efficiency defect passivation materials and designed and developed high-quality interface passivation structures.

According to Li Zhenguo, Founder and President of LONGi, the company has prioritized R&D and innovation since its establishment and has invested heavily in research and development to become the industry leader in R&D investment. LONGi will continue to be committed to technological innovation and transform advanced technologies into practical applications.