The solid-state battery specialist and Volkswagen partner QuantumScape has integrated a new separator manufacturing process into the basic production process of its battery cells. The company hopes that this will lead to “important improvements in separator quality and process stability”.
In a statement for investors, US solid-state battery developer QuantumScape announced that it has now implemented its “Cobra” process for the production of ceramic separators. The separators are a key component of QuantumScape’s planned lithium-metal battery cells with solid electrolyte. The new manufacturing process is said to be faster, more energy-efficient and less space-consuming. The company claims that Cobra offers a ~25x improvement in heat treatment speed and occupies a fraction of the physical space per film start compared to the prior-generation Raptor process.
The new manufacturing process is meant to improve the scalability of the cells, initially creating the basis for the production of B1 samples on a larger scale. At the end of last year, in December 2024, the US solid-state battery said it had laid the foundations for producing larger quantities of its B-sample cells in 2025 with the completion of the installation of its separator production plant. QuantumScape began producing small quantities of its first B-sample cells at the end of October 2024 without the “Cobra process” that should now enable it to produce on a larger scale.
“Cobra is a step-change innovation in ceramic processing, enabling a major improvement in productivity compared to Raptor, which was already a considerable advancement compared to the previous generation,” said Tim Holme, QS co-founder and CTO. “This advancement is central to bringing our high-performance solid-state battery platform to market at gigawatt scale.”
The B-sample cell called QSE-5 is set to become QuantumScape’s first commercial product, with a capacity of 5 Ah, an energy density of over 844 Wh/l and a charging time of 12.2 minutes from 10% to 80% SoC (State of Charge). Volkswagen’s battery subsidiary PowerCo is aiming to industrialise solid-state batteries for which the carmaking giant concluded a deal with QuantumScape in July 2024. The aim is a license partnership for “series production of solid-state cells on a gigawatt-hour scale”.
The production of solid-state batteries is being prepared across the electric automotive industry. CATL and SAIC aim to begin small-scale production in 2027, Toyota has said it will launch its first models with solid-state batteries between 2027 and 2028, BMW has already begun road testing with a prototype i7, and Gotion began pilot production of a solid-state battery in May 2025. Earlier this year, BYD‘s Chief Technology Officer revealed that the company had already produced its first solid-state batteries last year, but does not expect series production in the near future. Earlier this month, Xiaomi registered a patent for a solid-state battery.
