Huasun Energy has recently achieved two breakthroughs in the field of crystalline silicon
heterojunction (HJT) and perovskite tandem solar cells: 34.02% efficiency in a small-size
(1 cm²) laboratory cell and 29.01% efficiency in a large-size (210 HP) cell on the
production line. This milestone showcases Huasun’s innovation and its leadership in
commercializing tandem solar cell technology, bridging the gap from laboratory research
to industrialization.
At the laboratory level, the team innovatively introduced a dual passivation strategy
combining physical field effects and chemical bonds, which significantly reduced
interfacial non-radiative recombination losses. As a result, the small-size HJT-perovskite
tandem solar cell efficiency was successfully raised to 34.02%, ranking as the global
leaders. At the same time, by applying new perovskite crystallization additives and high-
mobility carrier transport layer materials, along with a series of material and process
improvements, Huasun team achieved comprehensive optimization of grain orientation,
energy level alignment, and interface stability—laying a solid foundation for further
exploring efficiency limits.
At the industrial level, Huasun’s self-developed production line achieved 29.01%
efficiency on large-size tandem solar cells (210 HP) — nearly 4% higher than single-
junction crystalline silicon solar cells. This breakthrough was enabled by the Huasun’s
large-texture thin-film deposition technology, which ensures uniform coating on complex
surfaces and overcomes key challenges in scaling perovskite materials. By introducing
organic stabilizers, Huasun improved deposition uniformity and environmental stability,
while new interface transport materials enhanced reliability and process compatibility.
Together, these advances move tandem cells a major step closer to mass production.
Tandem solar cells are widely regarded as the key to breaking through the efficiency
limits of crystalline silicon. Huasun’s dual breakthroughs—34.02% in small-size HJT-
perovskite tandem solar cells and 29.01% in large-size cells of production—not only
prove the theoretical feasibility and practical scalability of tandem technology, but also
underscore its strategic value. Once tandem efficiency exceeds 30%, solar power costs
can fall below one US cent per watt, paving the way for cost-competitive green hydrogen
and energy storage.
This breakthrough demonstrates the enormous potential of HJT-perovskite tandem solar
cells beyond single-junction counter and provides a scalable model for industrial
production, opening a more efficient and cost-effective path for the global energy
transition. It also strengthens industry confidence in producing high-efficiency, low-cost
tandem cells at scale, accelerating upgrades in heterojunction technology and their
adoption in the photovoltaic sector.