Corporate Research & Development Center

Toshiba has achieved the world's highest energy conversion efficiency ^{(Note 1)} of 9.9% for a 5cm×5cm organic thin-film solar cell module. In the cell, also, Toshiba has realized the world's highest level of conversion efficiency of 11.2% This achievement marks a step forward toward the realization of thin, low-cost, and lightweight organic thin-film solar cells.
The technical details were presented as part of the "Projects for Development of Solar Photovoltaics System Next-Generation High-Performance Technology" led by the New Energy and Industrial Technology Development Organization (NEDO) at the Grand Renewable Energy 2014 International Conference and Exhibition held at Tokyo Big Sight on July 29.

With the sharp increase in photovoltaic power generation, there has been strong demand to lower the cost of photovoltaic generation, and the reduction in feed-in tariffs has attracted much discussion in recent years. In addition, there are limitations on where the current type of silicon solar cell can be installed because of its weight and shape. To address these issues, an organic thin-film solar cell that is cheap, lightweight, flexible, and suitable for mass production is needed. However, the organic thin-film solar cell has a low energy conversion efficiency; an efficiency of more than 13% is required for practical use of the cell.

Toshiba has successfully improved the cell energy conversion efficiency by adopting a stable inverted architecture and using an improved version of the p-type material with longer wavelength absorption it has developed. Moreover, Toshiba's own "meniscus coating method" is used to form uniform multi-layer films with nano-scaled thickness and highly accurate patterns on the cell, while simulation technology is used to optimize the module structure. As a result, Toshiba has developed a module with the world's highest energy conversion efficiency and a high fill factor ^{(Note 2)}.

To further reduce the cost of power generation, we are continuing to develop technology and products to improve durability, raise conversion efficiency, and reduce manufacturing cost.