SOURCE / PRESS RELEASE
LONGi breaks record again for efficiency of silicon-perovskite tandem solar cells
Published: Jun 20, 2024 11:37 PM
On June 14th, at the highly anticipated 2024 SNEC Expo in Shanghai, LONGi Green Energy Technology Co., Ltd. (hereinafter referred to as "LONGi ") announced a major breakthrough in the development of its silicon-perovskite tandem solar cells.

According to authoritative certification by the European Solar Test Installation (ESTI), one of the world's leading photovoltaic (PV) calibration laboratories, this cell's photovoltaic conversion efficiency has reached 34.6 percent. This achievement once again breaks the world record for silicon-perovskite tandem cell efficiency previously set by the LONGi team. 

Following a pragmatic and empirical research approach, LONGi's cell R&D team has consistently garnered independent certifications from internationally recognized 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 Installation (ESTI) over the years.

Photo: Courtesy of the LONGi Green Energy Technology Co., Ltd.

Photo: Courtesy of the LONGi Green Energy Technology Co., Ltd.


The silicon-perovskite tandem solar cell, as the mainstream technology route for next-generation ultra-efficient solar cells, has a theoretical maximum efficiency of up to 43 percent, far surpassing the Shockley-Queisser limit efficiency of single-junction solar cells (33.7 percent). In November 2023, the LONGi tandem solar cell team achieved an efficiency of 33.9 percentfor tandem cells. Less than a year later, they have broken the record once again, demonstrating their strong R&D capabilities and relentless pursuit of exploration.

To achieve this breakthrough, LONGi's R&D team conducted extensive optimizations in several areas. They optimized the deposition process of the electron transport layer film, introduced high-efficiency defect passivation materials, and designed and developed high-quality interface passivation structures. These advancements were successfully implemented on LONGi's self-developed commercial CZ silicon wafer substrates, leading to a new milestone in silicon-perovskite tandem solar cell technology. By adopting a research model of "scientific root cause analysis + engineering lean optimization," the team achieved a 0.7 percent absolute efficiency improvement in just five months, elevating the efficiency of tandem solar cells to new heights.

The achievement of 34.6 percentefficiency not only demonstrates LONGi's profound expertise in tandem solar cell technology but also provides strong empirical support for the mainstream technological pathway of next-generation ultra-efficient solar cells. A representative from LONGi stated, "Our developed tandem cell technology can integrate with existing silicon-based cell processes, enabling an upgrade and iteration of current solar cell technologies. With our customized silicon wafers and a strong R&D team, LONGi will continue to drive the photovoltaic industry forward through technological innovation."

Last year, LONGi became the "Dual-Champion" of world record efficiencies in both mono-crystalline silicon single-junction cells and silicon-perovskite tandem solar cells. Over the years, LONGi has consistently adhered to a pragmatic and empirical research approach. LONGi's cell R&D team has repeatedly set new efficiency records in the global photovoltaic industry, with these achievements being documented in authoritative lists such as the Martin Green Solar Cell Efficiency Tables.

As a pioneer in setting world records for photovoltaic cell efficiency, LONGi's continued innovation and outstanding performance have not only contributed significantly to global solar power generation and green energy technology development but also demonstrated its determination and leadership in the photovoltaic industry. This underscores China's leading position in both mainstream technology tracks of mono-crystalline silicon single-junction solar cells and silicon-perovskite tandem solar cells.

Li Zhenguo, Founder and President of LONGi, emphasized that LONGi has prioritized R&D and innovation since its inception, sparing no expense in research and development, making it the industry leader in R&D investment. LONGi will continue to uphold its original commitment to technological innovation, steadfastly transforming advanced technologies into productive capacities, and persistently pursuing feasible technological innovations to create greater value for customers and contribute more to the industry.

Photo: Courtesy of the LONGi Green Energy Technology Co., Ltd.

Photo: Courtesy of the LONGi Green Energy Technology Co., Ltd.


LONGi's continuous innovation capability has not only earned recognition from certification bodies but also garnered favor through authoritative awards. Recently, Dr Xu Xixiang, Chief Scientist and Vice President of LONGi Central R&D Institute, was honored with the William R. Cherry Award by the Institute of Electrical and Electronics Engineers (IEEE). This award, often regarded as the "Nobel Prize" of the photovoltaic industry, marks Dr Xu as the first Chinese scientist to receive this prestigious reputation.

Photo: Courtesy of the LONGi Green Energy Technology Co., Ltd.

Photo: Courtesy of the LONGi Green Energy Technology Co., Ltd.


The William R. Cherry Award is named in honor of William R. Cherry, a pioneer in the photovoltaic industry. Established in 1980, this prestigious award selects one recipient globally each year to recognize engineers or scientists who have made significant contributions to the scientific and technical advancement of photovoltaic energy conversion throughout their careers. Nominees must demonstrate outstanding contributions and impact in the field through extensive publications and presentations. The William R. Cherry Award is considered one of the most authoritative and influential accolades in the photovoltaic field, representing the highest honor and achievement in photovoltaic research.

About LONGi

Founded in 2000, LONGi is committed to being the world's leading solar technology company, focusing on customer-driven value creation of a comprehensive energy transformation.

Under its mission of "making the best of solar energy to build a green world", LONGi has dedicated itself to technology innovation and established five business sectors, covering mono silicon wafers, cells and modules, commercial & industrial distributed solar solutions, green energy solutions and hydrogen equipment. The company has honed its capabilities to provide green energy and has more recently also embraced green hydrogen products and solutions to support global zero carbon development. www.longi.com