Solar energy continues to grow as a key pillar of the global energy transition, but improving performance while keeping costs low remains a constant challenge.
Now, a research team in China has demonstrated a major step forward: an industrial solar cell that reaches record-level efficiency while using less silver and capturing more sunlight from both sides.
The work was led by Professor Ye Jichun at the Ningbo Institute of Materials Technology and Engineering, part of the Chinese Academy of Sciences, in collaboration with industry partners.
Their results were published in the journal Joule.
The team focused on a technology known as tunnel oxide passivating contact, or TOPCon. TOPCon solar cells have rapidly become the dominant type of crystalline silicon solar cell, accounting for more than 70% of the global market.
They are popular because they combine high efficiency with reliability and are well suited to large-scale manufacturing.
Despite their success, TOPCon cells still face practical limitations. Manufacturing them requires large amounts of silver paste for electrical contacts, which adds cost.
Some of the cell structure also absorbs light that could otherwise generate electricity, and many designs do not fully take advantage of bifacial operation, where sunlight is collected from both the front and back of the panel.
To overcome these problems, the researchers developed a set of improvements designed specifically for industrial production. Using standard large-format M10 silicon wafers, they introduced a high-precision steel stencil printing process to create the thin metal lines on the front of the solar cell.
These ultra-narrow metal fingers reduce shading on the cell surface and significantly cut down silver use.
In fact, the new design reduces silver consumption by about 0.12 milligrams per watt of power produced. Combined with an improved silver paste, the process creates extremely small and dense silver contact points at the interface with the silicon. This allows electricity to flow efficiently while maintaining excellent electrical contact.
At the same time, the team redesigned the back side of the solar cell. By using a localized contact structure, they reduced unwanted absorption of light inside the cell.
This change dramatically improved bifacial performance, allowing the rear side of the cell to generate almost as much electricity as the front. The resulting bifaciality reached around 90%, which is exceptionally high for industrial solar cells.
Together, these innovations delivered impressive results. The researchers produced a TOPCon solar cell with a certified power conversion efficiency of 26.09%, placing it among the most efficient industrial silicon solar cells ever made. Crucially, this achievement did not require expensive materials or complex manufacturing steps, making it suitable for mass production.
The significance of the work lies in breaking a long-standing trade-off. Traditionally, improving efficiency meant higher costs or poorer bifacial performance. This new approach shows that it is possible to improve all three at once.
As solar power becomes ever more important for meeting global energy needs, technologies that deliver more electricity at lower cost are essential. This study provides a clear and scalable path toward the next generation of high-performance, affordable solar panels.
