RotH2, a French manufacturer of very high-pressure seamless steel cylinders based in Mions, Auvergne-Rhône-Alpes, completed a €6.6 million capital increase in December 2025. The funding included €2.7 million from new investors.
Founded in 1975, RotH2 specializes in hot flow forming forging, a technique it alone masters in France. Originally serving diving cylinders and accumulator shells, the company shifted focus after the Marsac family acquired it in 2021. It now targets industrial gas storage, especially hydrogen, along with hybrid racks and transport systems.
In recent years, RotH2 developed Type II cylinders rated for up to 1,000 bar pressure, a European first, and obtained 2014/68/EU PED certification for these from Bureau Veritas in June 2024. The firm also designed certified hybrid transport racks for 500 and 1,000 bar and industrialized solutions like micro refueling stations for hydrogen.
The capital will support R&D on Type V tanks, bolster working capital for sales growth, and upgrade production to meet future standards. Quentin Marsac, RotH2 CEO, stated: Since acquiring the company in 2021, we have achieved several industrial successes with major innovations in the field of high-pressure gas storage. This capital increase will allow us, in addition to supporting our operations, to significantly strengthen our R&D. Our ambition is to become one of the European leaders in the storage, transport, and refueling of very high-pressure gases.
RotH2 provides hydrogen solutions including 1,000-bar cylinders, certified racks, and refueling stations, positioning it within the hydrogen value chain from production to end use.