UK-based Palmer Energy Technology Limited (PETL), a battery energy storage system startup, has acquired Oxford University spin-out Brill Power in a strategic move to bolster its position in the Battery Energy Storage Systems (BESS) market.
The deal is accompanied by a fresh Series A funding round of approximately €5.7 million, co-led by FirstGroup Energy Limited, the energy investment arm of FirstGroup plc, alongside Barclays Climate Ventures and the University of Oxford.
“PETL’s acquisition of Brill Power enables us to embed the Brill software in all of our systems, instantly giving PETL a leading position in the space to serve customers such as FirstGroup,” said Andy Palmer, CEO and Co‑founder of PETL. “With buses at the forefront of the transition to electric vehicles and net zero transportation, I’m delighted to welcome investment from FirstGroup, as well as Barclays and Oxford University, to advance development of next generation control systems. This will allow us to accelerate our business and give the UK a leading position in BESS technology.”
Founded in 2024 by former Aston Martin CEO and Nissan COO Dr Andy Palmer CMG and entrepreneur Wei Shao, PETL applies automotive-grade engineering to stationary battery systems.
The integration of Brill Power’s technology – known for its cell-level control and active balancing in battery management – marks a major milestone for the company’s evolution. PETL will immediately embed Brill Power’s platform across all systems, aiming to extend battery lifespan, increase safety, and deliver higher energy efficiency.
Founded in 2016, Brill Power emerged from academic research conducted at the University of Oxford. The company’s core innovation lies in battery control software that can actively balance current flow from each cell based on individual state of health – a method that improves both performance and safety.
All software is engineered and validated in the UK, with data stored on domestic servers to ensure compliance and security.
While Brill Power’s technology will now power PETL’s integrated systems, the brand itself will continue to operate independently for module sales to third parties. The acquisition aligns with PETL’s broader strategy to expand UK-based manufacturing, enhance supply chain control, and deliver high-quality products for industrial, grid, and transport applications.
“This investment continues our strategy of backing new and innovative companies aimed at supporting our long-term public commitment of achieving a zero emission fleet by 2035,” said Faizan Muhammad, Investment Director at FirstGroup plc. “PETL, along with its acquisition of Brill Power, will unlock innovative energy procurement solutions whilst providing second life use cases when batteries are taken off electric buses.”
Adam Workman, Head of Investments and New Ventures at Oxford University Innovation, also underscored the deal’s importance in commercialising novel energy platforms.
“It is great to see the coming together of PETL and Brill Power to accelerate their novel energy storage technologies. Alongside FirstGroup, we hope that the combined business will accelerate the commercialisation of its energy platforms.”
Read the orginal article: https://www.eu-startups.com/2025/08/british-startup-palmer-energy-technology-acquires-brill-power-in-merger-backed-by-e5-7-million-raise/
