In the framework of the Horizon 2020 HIGHLITE project, CEA at INES is developing shingle technology applied to high performance heterojunction solar cells (HJT) and high density/high power for the commercial and industrial roofing market - a promising series of pre-industrial modules has just been produced.
Crédits : CEA
Heterojunction modules with shingle interconnection ready for industrialization
Published on 09/16/2021
The new cell interconnection technology called shingle is appealing to the photovoltaic community because it offers higher power densities at a competitive cost. Its advantages over standard modules include lower resistive losses, better surface utilization, higher energy efficiency, and a better aesthetic appearance important in the building market.
The cells integrated using this technology are cut into strips (in our case 6 strips) and the current they generate corresponds to the initial current generated before cutting, divided by the number of strips.
The module is then assembled without any metal ribbon welded to the cells or gaps between the cells and therefore has a higher active surface fill than a standard module.
CEA has tested and evaluated different designs and topologies for this technology, under IEC 61215 conditions, to select a suitable, efficient and reliable process and bill of material. A first semi-industrial manufacturing campaign has just been completed and resulted in the production of 10 Shingle HJT modules, of approximately 320 Watts for an equivalent size of 60 cells, designed to meet the needs of Building Applied PV (BAPV) applications in terms of weight reduction, high area performance and aesthetics.
The modules are made of "classic" M2 size heterojunction cells manufactured on the CEA's pilot line at INES, neither selected nor treated, in a glass front and back configuration, with some of them with a non-blocking UV encapsulant.
They have an average power of 315.64 W, i.e. 209.5 W/m², with a relative standard variation of 0.34%, and therefore excellent reproducibility of the manufacturing and characterization methods used.
Modules with non-blocking UV encapsulant reach an average front side power equal to 322.64 W or 214.15 W/m², thus gaining more than 2% in power.
The average efficiency is 21.41% (active area) for modules with non-blocking UV encapsulant, and 20.95% for the others. On the total surface area, the module efficiency is 19.5%.
The module weighs 19.6 kg, i.e. a surface weight of 11.8 kg/m², a gain of about one third compared to a standard module (about 18 kg/m²).
These results place these modules in the top 5 worldwide on the scale of industrial HJT modules of the same type in terms of density (W/m²).
They are fruit of close collaboration with the other partners of the HIGHLITE project such as Applied Materials Italy.
The laboratory tests show an excellent reliability of the interconnection, with a large majority of the samples having resisted 3 times the norm, and even 4 times for some.
The mechanical and electrical resistance of these modules will continue to be tested outdoors for at least a year, in the south of France, on the CEA site at Cadarache.
CEA-INES shows here the maturity it has acquired on the shingle technology applied to heterojunction for the BAPV market segment, still very little present on the world market. The way is open for the deployment of this technology in the industry.
This project has received funding from the European Union’s Horizon2020 Programme for research, technological development and demonstration under Grant Agreement no. 857793.