DELO Light-curing adhesives based on epoxy resins or acrylates are particularly well-suited for bonding protective films on thin-film solar cells while simultaneously forming an effective barrier against humidity.
Applications of thin-film solar cells
Flexible thin-film solar cells can be used for facades, lightweight roofs or charging columns, as well as indoors to supplement or directly replace button cell batteries in various applications (e.g. electronic price tags). These are areas of application in which classic silicon-crystalline modules are reaching their technical limits. Flexible thin-film solar cells are only a few millimetres thick. The active, energy-producing layers often consist of organic materials that are extremely sensitive to moisture and oxygen, so the solar cells are usually covered with a protective film on the front and back.
DELO KATIOBOND LP6656: Reliable protection
One adhesive that can be used to reliably bond the protective film is DELO KATIOBOND LP6656. Along with bonding, this light-curing epoxy resin also acts as a barrier and effectively protects the active layers from humidity. This is especially important at the edges, as humidity would impair the solar cells' functionality if penetrated. Thanks to the raw materials used, the adhesive has a low water vapor transmission rate of 8 g per mm/m² in 24 h, which has been tested at a temperature of +60 °C and a relative humidity of 90%. This prevents premature degradation of the solar cells and contributes to a long lifetime. At the same time, the efficiency of the solar cell is not affected, as the adhesive is highly transparent in the typical layer thicknesses. The compatibility of the adhesive with the active organic layer has also already been successfully tested in close collaboration with co-operation partners and customers.
DELO KATIOBOND LP6656 also features high peel resistance on PET, the plastic material typically used for protective films. The transparent adhesive cures in seconds under UV light and has been optimized for slot-die coating. With this process, extremely thin adhesive layers can be applied, enabling efficient and controllable processing. Also, for roll-to-roll processes, DELO has various products based on epoxy resins and acrylates, such as DELO PHOTOBOND.
All advantages at a glance:
- Low water vapor transmission rate of 8 g per mm/m² in 24 h
- Good peel strength on PET
- Customised viscosity that enables slot-die coating
- Compatibility with organic active layer
- High transparency in typical film thicknesses
- Curing in a few seconds with UV light (400 nm or 365 nm wavelength)
Further details can be found in our brochure.
Diverse solutions for renewable energy
In addition to adhesive systems for organic thin-film solar cells, we also offer adhesives for the sealing and lamination of perovskite solar cells. Perovskite is a class of mineral that is used in particular in thin-film solar cell technology and is gradually conquering the market due to its outstanding material properties. In combination with conventional silicon modules to form so-called tandem solar cells, it is seen as a pioneering technology. Perovskites react sensitively to moisture and oxygen in a similar way to organic materials and can therefore degrade considerably. This means that effective protection concepts are also required here.
Furthermore, DELO provides adhesive solutions for other technologies in renewable energy, including wind power and battery systems for electric cars. Thanks to their multifunctionality, these adhesives can perform other tasks in addition to reliably bonding two components. More information can be found on our application field website pages.
If you want to expand your knowledge on bonding technology, check out DELO Academy. These training courses are worthwhile for engineers and developers, providing insights in various applications as well as valuable tips.
Do you have any specific questions or bonding challenges? Our experts will be happy to advise you: Project consulting.
