Objective and targets
DURACIS aims to achieve a significant breakthrough in the competitiveness and durability of flexible CIGS technologies by the development of new encapsulation solutions and concepts. The main project objectives are:
i) Development and validation of new and innovative low cost encapsulation and optical glue materials and concepts for flexible CIGS PV, based on the transfer of alternative approaches from organic based technologies. Assessment of the processes will include the analysis of their transfer to industrial CIGS pilot lines available in the consortium
ii) Development of advanced methodologies for the non-destructive monitoring of the encapsulation processes and layers.
The main technical milestones are:
1.- Demonstration of new encapsulation concepts for the development of cost efficient encapsulation solutions for flexible light weight CIGS devices involving: i) Device efficiency ≥ 95% of efficiency achieved with similar reference devices with rigid glass-based encapsulation; ii) Resistance against weathering (DH2000); iii) Water vapour transmission rate ≤ 10-3 g/m2/d (38o C/ 90% r.h.);
2.- Demonstration of scalability of the proposed solutions to the industrial production of flexible light weight CIGS modules.
Main expected result is the development of new encapsulation solutions for flexible light weight CIGS PV technologies with a targeted cost < 15 €/m2 and a lifetime of 25 years and compatible with a long term lifetime target of 40 years, as well as the demonstration of the compatibility of these solution with the main industrial flexible CIGS PV technologies (based on either polyimide or steel substrates)
Major scientific, technical and commercial challenges
Main scientific and technical challenges of DURACIS are related to the development of new cost efficient and flexible encapsulant solutions that are inspired in concepts that have been proposed and developed in organic technologies as OLED and OPV. In the first case, many OLED industries have focused their development on based-glue improvements or on thin film encapsulation. Specific solutions that will be developed involve methodologies based in glue type layers and polymers deposited following a hybrid procedure together with ALD Al2O3 and TiO2 layers. DURACIS will include also high innovative concepts based in the barriers developed by ECOPOL for nanocapsules and microcapsules. Innovation is related to the development of multifunctional reactive polymers that show self-stratifiying properties depending on the hydrophobic/hydrophilic environment. The prepolymer mixture shows amphiphilic behaviour when acts as a coating due to the rearrangement of the different polymers. The hydrophilic-hydrophobic polymers rearrange layer-by-layer giving a hydrophilia-hydrophobia polymer gradient, where the most hydrophobic will be in contact with moisture and oxygen. This avoids the need to have a with high-fluorine content in order to obtain a hydrophobic/oleophobic coating, and opens the possibility for development of layers with total thicknesses below 500 µm, thus allowing a significant reduction of materials costs. In addition, a complementary encapsulation concept based on specially modified polyolefin embedding films as well as a transparent protective film (protection against weathering) will be developed by Solinext.
DURACIS will develop new cost efficient encapsulants based in the transfer of concepts developed for organic technologies. DURACIS aims to solve one of the main problems in industrial flexible CIGS technologies, related to the very high costs of the existing encapsulant solutions (35-45 €/m2). The cost target defined in DURACIS will allow achieving encapsulant costs consistent with those of glass-to-glass CIGS solutions which are already competitive with the market dominant Si PV technology. This will contribute to an enhanced acceptance of flexible CIGS solutions with an increase in the share in markets with strong growing potential like BIPV (where an annual increase of 18.7% is expected in the next 4 years, with a predicted BIPV installed capacity > 1.1 GW in 2019).