Researchers at the National Institute of Advanced Industrial Science and Technology in Japan have developed a thin film that could help reduce degradation in the output of solar cells.

The technology puts a thin-film coating of titanium oxide-based composite metal compound on the glass substrate used in photovoltaic modules. This suppresses the diffusion of sodium ions, etc. from the glass substrate that is considered the major cause of PID (potential-induced degradation). The developed technology is expected to further enhance the reliability of crystalline silicon photovoltaic modules and help enhance the long-term reliability of mega solar and other solar power generation systems, installation of which is expected to accelerate in the near future.

PID can take place in as little as a few months or over several years. This caused there to be reports of rapid declines in output capacity of solar power generation systems. The use of the titanium oxide-based composite material greatly improves the longevity of the systems, like the solar power plants in Japan.

This technology has great potential for dealing with the PID phenomenon at low cost, for several reasons: the titanium oxide-based composite metal compound is relatively inexpensive, the film can be formed by a simple coating method and annealing at low temperature, and a small amount of material is used.

The researchers will seek to optimize the materials, film thickness, film-forming conditions, and so on for the thin film of titanium oxide-based composite metal compound in order to better suppress PID and verify the improved suppression. They also plan to elucidate the mechanism of PID suppression in more detail, conduct demonstrative tests with modules of larger surface area, and conduct other research and development, aiming at early commercialization of the developed technology.

To read more, visit R&D Magazine.