World record efficiency of 28.13% for silicon solar cell

Longi claims to have achieved the world’s highest efficiency for a silicon solar cell. The result was confirmed by Germany’s Institute for Solar Energy Research Hamelin (ISFH).

April 28, 2026 Emiliano Bellini

A few hours after Trina Solar revealed it achieved the world’s highest efficiency for silicon solar cells with 28.0%-efficient device TOPCon-compatible hybrid back-contact solar cell (THBC), Chinese module manufacturer Longi announced it achieved a higher efficiency of 28.13% with a hybrid nterdigitated-back-contact (HIBC) solar cell.

The result was independently confirmed by Germany’s Institute for Solar Energy Research Hamelin (ISFH).

Longi also said that HIBC-based modules with an efficiency of 26.4% were certified by the U.S. National Renewable Energy Laboratory (NREL). “These breakthroughs in technological capability have already translated into a leading edge in mass production,” the company said in a statement.

Longi outlined details of its HIBC solar cell architecture in a scientific paper published in November. The company said the device combines passivated tunneling contacts, dielectric passivation layers, and both n-type and p-type contacts.

The cell is built on a high-resistivity half-cut M10 wafer featuring edge passivation and optimized n-type contacts produced through a combined high- and low-temperature process. An indium tin oxide (ITO) layer improves lateral transport, while multilayer aluminum oxide (AlOx) and silicon nitride (SiNx) coatings reduce surface recombination.

The researchers also reduced phosphorus doping in the n-type polycrystalline silicon layer to limit dopant diffusion into the wafer. The company’s in situ passivated edge technology enables edge passivation during fabrication. In addition, deep-trenched metal fingers and selective ITO etching help prevent leakage between n-type and p-type contacts, while a thicker amorphous silicon layer improves junction coverage and sidewall encapsulation. To reduce contact resistivity without compromising passivation, the amorphous silicon layer is crystallized using a pulsed green nanosecond laser.

Longi said the technology could be scaled for heterojunction solar cell manufacturing, although additional improvements are still needed to reduce resistive losses in the p-type contact.

Longi, Trina Solar report losses

Longi says its 2025 revenue and losses declined year on year, while Trina Solar reports deeper full-year losses and margin pressure across its core module business.

May 1, 2026 Vincent Shaw

Longi Green Energy has reported 2025 revenue of CNY 70.347 billion ($10.3 billion), down 14.82% year on year, with a net loss attributable to shareholders of CNY 6.420 billion, narrowing from the previous year. Gross margin stood at 0.81% and net margin at -9.13%, indicating operations close to break-even. The company shipped 111.56 GW of monocrystalline wafers and 86.58 GW of modules, while external cell sales reached 4.31 GW. Operating cash flow turned positive to CNY 4.359 billion, as total operating costs fell 8.72% and sales and administrative expenses declined 29.96% and 23.67%, respectively.