The ceramic sheet in an SOFC serves as the solid electrolyte, passing oxygen ions to interact with hydrogen ions and generate electricity, the newspaper said.

The company currently operates a research-level plant that can make the sheets at a rate of 100,000 units a year, and it supplies the sheets to the Swiss SOFC maker Sulzer Hexis, as well as to Toho Gas Co Ltd and Sumitomo Precision Products Co Ltd, it said.

But with fuel-cell makers starting to take SOFCs to the practical level for household applications, the firm decided to invest nearly 1 bln yen to build a new plant that will boost its production capacity tenfold to 1 mln sheets a year, the report added.