Hi-MO X6 Ultra Black: LONGi launches premium black dual-glass back contact module with higher reliability and safety

Global News

At Intersolar 2024, LONGi officially unveiled its new Hi-MO X6 Artist Ultra Black module with a 360-degree pure black appearance. LONGi achieves this new level of black through a special glass surface structure and a premium cell selection process using automated optical inspection (AOI) during the manufacturing process. In addition, the dual-glass module features a thicker glass front and POE film (Polyolefin Elastomer) for the module’s encapsulation, providing higher reliability and safety. Its bifacial characteristics make it suitable for a variety of rooftop PV application scenarios such as carports and winter gardens. With LONGi’s high-efficiency HPBC technology (Hybrid Passivated Back Contact) the modules generate up to 1.54% more power than TOPCon modules under low light conditions – extending the power generating hours per day. The Hi-MO X6 Artist Ultra Black module series is LONGi’s response to the growing demand for aesthetically pleasing solar modules in the residential sector and is available in Europe now. The module generates up to 435W at an efficiency of 22.3% and it comes with a product warranty of 25 years and a power warranty of 30 years.

Hi-MO X6 Artist Ultra Black honored with two Design Awards for premium aesthetics 

The consistent deep black appearance from a multi-angle view results from two main features: 

  1. The HPBC Black cell has a low-reflective texture and provides deeper light trapping, reducing reflection and increasing light absorption by 1.2%. This keeps the sunrays inside the cell, enabling a high-efficiency photovoltaic conversion. The structured glass uses the principle of diffuse reflection. It evenly reflects light that strikes the glass multiple times in different directions, creating a consistent 360-degree black optical effect at different installation angles. 
  2. LONGi has developed a new standard black for the Ultra Black module and an image recognition process that detects different levels of black in the cells. Using AOI, the cells for the Ultra Black production are being evaluated on a multi-dimensional level and selected according to the Ultra Black color standard. This process results in pure, deep black cells in the modules. 

The Hi-MO X6 Artist Ultra Black and its aesthetic values have received two major design awards prior to its market launch: the “Gold Winner of 2024” from the French Design Awards and “IRON Winner of 2024” from A' Design Award & Competition 

LONGi’s HPBC back contact technology provides 2% better light absorption than TOPCon modules in the same power class 

The Hi-MO X6 Artist Ultra Black features LONGi’s proprietary developed high efficiency HPBC (Hybrid Passivated Back Contact) cells. The back-contact technology allows for a gridless and busbar-free front for lossless light absorption. Without any shading, the light absorption is increased by more than 2% compared to TOPCon modules with the same power. This is one of the key results of long-term tests conducted by LONGi under the same conditions. Ultimately this results in lower LCOE. In addition, the front has a sleek appearance for improved aesthetics.  

Thicker glass front and upgraded module frame withstand higher mechanical stress 

LONGi chose to use 2.00 mm thick glass for the front surface instead of 1.6 mm which is the standard for 54-cell modules. The additional 0.4 mm provides 56% greater bending stress resistance. As a result, the module can withstand high wind speeds in excess of 120 km/h (12 Bft) and heavy snow loads without breaking. It also improves impact resistance against hailstorms, far exceeding IEC standard tests (25 mm hailstones at 23 m/s). The module has been successfully tested by TÜV Rheinland according to IEC61215-2 with 35 mm hailstones at 110 km/h. The back uses standard 1.6 mm thick glass, because it is subject to less mechanical stress than the front. 

With glass on both sides, the module also has higher fire safety and better heat dissipation. The latter results in more stable power generation under high temperature conditions.  

Additionally, the module frame has been upgraded: Non-slip grooves have been added to improve contact between clamp and module frame. Therefore, the load capacity has been enhanced. As a result, the front can withstand a mechanical load of 6000 Pa and the back 3600 Pa. 

A POE film is reducing degradation 

LONGi has improved the encapsulation system of the modules with double-sided POE film. It has better thermal stability and UV resistance than the EVA (ethylene vinyl acetate) film used in standard TOPCon modules, effectively slowing module aging. It also offers improved steam resistance to help prevent corrosion. This leads to a reduced module PID (potential induced degradation) with a power generation of 86.9% after 30 years.  

The bifacial upgrade opens up more PV application scenarios 

Designed for versatility, the Hi-MO X6 Artist Ultra Black modules address a wide range of PV application scenarios, including residential, commercial and industrial rooftops, carports, winter gardens and conservatories. Their bifacial design enables efficient power generation by effectively utilizing light reflected off the rear side for additional power generation gains. This makes the Hi-MO X6 series an ideal choice for locations that require high weather resistance and safe, reliable operation. 

Steady focus on back contact technology as the solar technology of the future  

LONGi's Hi-MO X6 Artist Ultra Black with dual-glass is an example of the company's continued focus on back-contact technology. LONGi continues to implement its upgraded HPBC technology with low-reflective textured technology in various module types and underlying technologies. Most recently, LONGi announced that it has broken another world record for silicon solar cell efficiency, just 4 months after setting the previous world record. As certified by Germany's Institute for Solar Energy Research Hameln (ISFH), LONGi's new silicon heterojunction back-contact (HBC) solar cells have achieved an efficiency of 27.30% under laboratory conditions. 

Press Contact

Nadine Bütow

Head of European Communications (DG)



Timo Helmke

PR Manager Europe (DG)