Seventeen years later, LONGi says its analysis group has reached 35.5% power-conversion effectivity with a crystalline silicon-perovskite tandem photo voltaic cell, as per a report. The outcome was independently licensed by the European Photo voltaic Check Set up, or ESTI.
The 35.5% determine applies to a analysis cell reasonably than a industrial photo voltaic panel. LONGi’s announcement doesn’t specify the world of the most recent cell or present an accompanying peer-reviewed paper, so some technical particulars are usually not but accessible.
How perovskite photo voltaic cells developed
The unique 2009 machine used methylammonium lead iodide nanocrystals to sensitize a porous titanium-dioxide electrode, as per a ScienceBlog report. It transformed 3.8% of incoming photo voltaic vitality, nevertheless it relied on a liquid electrolyte that dissolved the perovskite. Its efficiency might decline inside minutes.
Researchers later moved towards strong transport layers, improved crystal development, diminished defects, and developed methods to guard the skinny interfaces between supplies.
Perovskite refers to a crystal construction reasonably than one mounted substance. Its composition could be adjusted to vary its bandgap, permitting researchers to tune the way it absorbs daylight. That flexibility grew to become significantly helpful when perovskite was mixed with silicon.
Why silicon and perovskite work collectively
A traditional silicon photo voltaic cell makes use of a single light-absorbing junction, which limits how successfully it may use the total photo voltaic spectrum. A tandem cell divides the job between two absorbers.The perovskite high cell absorbs higher-energy seen mild, whereas lower-energy crimson and near-infrared mild passes by to the silicon backside cell. The 2 supplies can due to this fact deal with completely different components of the spectrum.
This permits a tandem machine to exceed the effectivity limits of a single-junction silicon cell. Detailed calculations put the sensible theoretical ceiling for a single-junction crystalline silicon cell at roughly 29%, as per the ScienceBlog report.
Why 35.5% analysis effectivity is completely different from panel effectivity
LONGi’s 35.5% outcome applies to a analysis cell. A industrial module combines many cells throughout a a lot bigger space, including inactive borders, interconnections and different optical and electrical losses.
LONGi says its bigger tandem cells have reached 34.3% over 261 sq. centimeters and 32.2% over 274 sq. centimeters, as per the ScienceBlog report. Its tandem modules have reached 31.4% and 29.4%.
The figures present why laboratory cell effectivity and industrial module efficiency shouldn’t be handled as interchangeable.
The newest outcome follows LONGi’s 34.58% outcome
LONGi had beforehand reported a tandem effectivity of 34.58%. In a 2025 Nature paper, researchers described an uneven self-assembled molecule used as a hole-selective layer. The remedy improved protection over textured silicon and helped align vitality ranges on the buried interface.
The method helped helpful cost depart the perovskite whereas lowering alternatives for electrons and holes to recombine.
ESTI licensed that earlier machine at 34.58%. LONGi has not but supplied equal device-level particulars for the brand new 35.5% outcome, so it isn’t clear precisely what produced the extra 0.92 share factors.
The following problem is making the know-how sensible
Increased effectivity is just one a part of growing a usable photo voltaic know-how.
Perovskite tandems must function reliably over massive areas and face up to warmth, moisture and ultraviolet publicity over lengthy intervals. Manufacturing additionally wants to stay constant.
Many main perovskite compositions include lead, making strong encapsulation, leakage testing and accountable end-of-life dealing with essential.
A 2025 Nature Photonics evaluate recognized effectivity, long-term stability and scalability as linked challenges for the know-how. Progress in a single space doesn’t routinely clear up the others.
