Certain Energy, the new name of the Imperial College London spinout RFC Power, raised a £10m Series A on 26 August 2026. The British Business Bank led the round, investing £3.5m, according to Pulse 2.
Centrica, Ceres Power and Catalytic Capital for Climate and Health, a fund linked to Temasek Trust, also invested. No valuation was disclosed.
The company develops manganese flow batteries for long-duration energy storage, intended to stabilise grids and supply power when renewable output is low.
Ceres, which is listed on the London market, acquired RFC Power in September 2025. The round brings in outside investors alongside it. The sources do not state how Ceres's holding changed.
“Long-duration storage is the missing piece of the clean energy system”Dr. Tim von Werne, Chief Executive, Certain Energy
What Certain Energy does
Certain Energy's batteries use manganese chemistry. The company was created in 2017 as a spinout from Imperial College London, based on research by Professor Anthony Kucernak of chemistry and Professor Nigel Brandon of earth science and engineering.
It is based at the I-HUB on Imperial's White City campus and previously received support from the Imperial Incubator and from Undaunted's accelerator, now called The Greenhouse. Ceres acquired RFC Power in September 2025, according to Ceres's announcement.
Ceres's page described the company's aim as stabilising grids and supplying power when renewable output is low, which is the use case for the long-duration storage it is developing.
What the money is for
The funds will go to commercialising the battery and scaling toward volume production. Specific plans include a grid-connected system of megawatt-hour class in India, an expanded UK research facility and the building of a supply chain for repeatable commercial projects.
The company's chief executive is Tim von Werne, with Mark Selby as executive chair, Ashkan Kavei as head of technology delivery and Chris Evans as chief product officer. The company did not disclose its headcount.
The Ceres announcement said the funds would also create a supply chain for future commercial deployments,.
What those involved said
Von Werne said long-duration storage is the missing piece of the clean energy system. Kucernak said the investment marks an important step towards bringing manganese flow batteries to the grid at scale.
Brandon, who is dean of the Faculty of Engineering at Imperial, said electrochemical technologies such as flow batteries have a key role to play. Michael Shanks, a minister at the Department for Energy Security and Net Zero, said homegrown clean energy is the route to more affordable bills and energy security.
Stuart Paynter, chief financial officer of Ceres, pointed to a low-cost, abundant chemistry and a credible, capital-efficient route to manufacturing, which is how Ceres describes manganese flow batteries.
The funding so far
The sources opened for this article do not itemise earlier funding other than Ceres's acquisition of RFC Power. The round is described as the company's Series A.
The British Business Bank's £3.5m would leave about £6.5m from the other investors, though the split among them was not reported.
Company website: certainenergy.co.uk