Ceres Power Holdings plc said it would spin off its battery unit RFC Power Ltd, which has been rebranded as Certain Energy, while retaining a 37% stake in the new company.
Certain Energy completed a £10 million Series A funding round led by the British Business Bank, with participation from Centrica plc, Ceres and Temasek Trust’s Catalytic Capital for Climate and Health. The company develops manganese flow battery technology focused on long-duration energy storage.
Ceres contributed £1 million in cash to the Series A round and will receive an additional £1.5 million in equity for in-kind engineering services. The unit was acquired by Ceres in September 2025 for a nominal amount, becoming a wholly owned subsidiary before the spin-off.
Certain Energy’s technology targets grid-scale energy storage, complementing Ceres’ core business in solid oxide fuel cell and electrolyser technology. Stuart Paynter, Ceres’ Chief Financial Officer, will join the board of Certain Energy. The company will also share future revenues with Ceres under the terms of the transaction.
The spin-off follows Ceres’ licensing-based business model, under which it develops and licenses fuel cell and electrolyser technologies rather than manufacturing end products.
