Toshiba trial production of organic thin film solar cells, module efficiency reached 7.7%

Toshiba produced an organic thin-film solar cell. The energy conversion efficiency of the 5cm square module reached 7.7%. This achievement was announced at the "73th Annual Applied Physics Society Academic Lecture in Autumn 2012" in Japan. In the conversion efficiency rankings of OPV modules that have been standardized, such as measurement methods, 5.2% of Sumitomo Chemical's previous rankings were among the highest in the world, and the Toshiba trial product significantly exceeded that of Sumitomo Chemical. In the world of solar cell technologies that have to compete for 0.1 percentage points, it is shocking to say that 2.5 percent of the conversion is equivalent to an increase in output power by about 50 percent. Toshiba's prototype conversion efficiency has also reached 9.2%, which is equal to the current highest global value announced - Mitsubishi Chemical's 10.0%.

The OPV manufactured by Toshiba is characterized by its proprietary coating technology called "Meniscus* printing method" for film formation. Toshiba R&D Center Chief Technology Officer Yaoya Yamo said, "I borrowed the company's organic EL development technology."

* Meniscus: When the liquid is poured into a container such as a beaker, due to the surface tension of the liquid and the resistance to contact with the container, the surface of the liquid surface is concave or convex.

Another feature is that conversion efficiency increases very quickly. Sosoya introduced: "The applied efficiency of the sub-modules introduced in the draft of the lecture of the Applied Physics Society was 6.2%, and it took only about three months after the official release and increased to 7.7% when it was officially released." Vector). This is mainly due to the long wavelength of the light absorption band and the high purity of the fullerene derivative of the n-type material using the p-type organic semiconductor material developed in-house. Toshiba has begun to make sub-modules of 20cm square, allegedly to obtain the same conversion efficiency as the 5cm square modules.

Shioya also said: "In the durability test, the battery has obtained basically the same results as the thin-film silicon solar cell. We hope to plan to produce a 30-cm square module with an efficiency of 10% as soon as possible and realize its practical application."