The new solar cell, made from the same material as most existing solar cells, has an impressive efficiency of 26.81%. These findings reaffirm the role of solar cells in the global shift to renewable energy. The research results were published in May 2023 in Nature Energy.

At first impossible

The breakthrough is the result of a collaboration between LONGi Green Energy Technology, Sun Yat-Sen University and Delft University of Technology. The team optimized the solar cell design by incorporating an improved "nanocrystalline-silicon hole contact layer." Although the concept of such a layer has been theoretically known for a long time, it has never been successfully put into practice.

Compared to other types of solar cells, this new layer allows the transfer of electricity with reduced resistance, resulting in superior power conversion efficiency. Researchers at LONGi developed this technology using standard silicon wafers, making it easy to apply in solar panel production. The cell's performance shows an absolute leap forward, with a 1.5% increase in conversion efficiency.

A revolution in efficiency and power conversion

Scientists at SYSU analyzed the electric current through the new layers. Their research showed that cells with the improved layers showed better electrical conductivity due to a low activation energy. Professor Gao Pingqi emphasizes the importance of research into silicon contact layers with low activation energy, as these benefit different types of solar cells and can accelerate the energy transition.

Only ten kilometers away from the Suncia office in Rotterdam, TU Delft researchers investigated the LONGi solar cell to better understand how it works. This analysis also provided insight into shortcomings to improve the performance of the solar cell. Postdoctoral researcher Paul Procel is enthusiastic about the improved material properties. Professor Olindo Isabella praises LONGi's mastery of ultra-thin solar cells and says boundaries have been pushed in solar cell technology.

The race to the best solar cell

Solar cells using HJT technology improve the power and efficiency of solar cells compared to other technologies such as PERC and TOPCon. The entire solar industry sees the potential of HJT technology. Meanwhile, in addition to LONGi, Maxwell, HuaSun, Reliance and Akcome have also started developing and offering HJT solar panels.

This breakthrough in solar cell design brings us closer to a clean and efficient solar energy future. With its remarkable efficiency and immediate applicability, this innovation lays the foundation for a more sustainable and renewable energy landscape.

However, the race is not yet won. Both HJT and TOPCon technology are still in the early stages of development and there is still much room for improvement in both camps. The TOPCon technique can be applied to existing PERC production lines, while the HJT technique cannot, so we expect that both techniques will be further developed. Keep an eye on our blog for more updates on technological developments in the solar industry.