The deal is subject to regulatory approval, Britishvolt said.
The startup said Nordhausen, Germany-based EAS is a "pioneer in developing and producing large format lithium-ion cells using innovative and compact electrode production technology" ideally suited for its own high-performance, long-range "46xx" battery cell format.
"The acquisition of EAS will allow us to scale up the final part of the 46xx cell development and commercialization," CEO Orral Nadjari said in a statement, adding Britishvolt aimed to make additional investments in EAS.
Britishvolt is working with British sports carmakers Aston Martin and Lotus to develop high-performance EV batteries.
Britishvolt has secured UK government backing for a battery plant project in northern England, unlocking 1.7 billion pounds ($2.12 billion) in private funding.
($1 = 0.9335 euros)
($1 = 0.8007 pounds)
(Reporting by Nick Carey; editing by Jason Neely)
By Nick Carey