Interview with Hans Beyer, Webasto
“Immersion cooling effectively suppresses thermal runaway propagation”
Hans Beyer studied chemistry at the Technical University of Munich, where he later completed his doctorate in environmental and heterogeneous catalysis.
Webasto
Higher charging power and performance demands are increasing the thermal load on EV batteries. Webasto’s Dr Hans Beyer explains when immersion cooling offers advantages and what challenges remain before it can reach volume production.
As charging power and battery performance increase, thermal management is becoming an increasingly important part of battery system design. Immersion cooling is one approach, with battery cells surrounded directly by an electrically insulating coolant. Dr Hans Beyer, Manager Battery Cell Integration, Materials & Bonding at Webasto, works on the integration of such technologies into battery systems.
At the Automotive Battery Conference 2026 in Munich, he will give the keynote “Immersion Cooling: Raising the Bar for Battery Performance”. In our interview, Beyer discusses where this method can outperform conventional cooling concepts and what still needs to be addressed in terms of material compatibility, manufacturing, safety and scalability.
The Automotive Battery Conference 2026 agenda spans resilience, scalable manufacturing, battery safety, lifecycle value and charging. Which issue will most decisively shape the battery and e-mobility industry over the next five years, and why?
Battery safety, lifecycle value and charging performance are all critical. However, the most decisive differentiator over the next five years will be the ability to translate advances in cell technology into measurable customer value at system level.
Webasto has demonstrated industrialisation excellence and resilience through battery manufacturing at scale in Germany, Slovakia and South Korea. Yet manufacturing capability alone will not secure competitiveness. As cell technology continues to evolve, OEMs increasingly require system partners capable of integrating the best available cells of any format, chemistry or supplier into safe, high-performance battery systems.
In this environment, enabling the full ultrafast-charging potential of current and future high-performance cells at system level while maintaining safety, durability and cost efficiency will become a key competitive advantage.
With thermal-runaway imaging, fire-protection materials and high-power charging also on the agenda, what is the key system-level question immersion cooling must answer before OEMs can adopt it at scale?
The key question is whether immersion cooling can deliver its performance benefits with a level of system complexity, cost and manufacturability suitable for high-volume applications.
Following the successful industrialisation of battery module and pack production for a high-performance vehicle, Webasto has demonstrated its expertise in advanced battery manufacturing. Building on this experience, the focus is now on developing lean immersion-cooling architectures that deliver meaningful charging and performance benefits while meeting the cost, reliability and scalability requirements of volume production.
With high-power charging also on the agenda, at what heat flux, charging power or cell-level temperature gradient does immersion cooling become technically superior to conventional cold-plate concepts – and which system-level penalty most often offsets that advantage?
Immersion cooling excels wherever thermal loads become a limiting factor for charging performance, power capability or temperature homogeneity at cell or pack level. The main trade-offs are increased complexity in design and manufacturing, stringent sealing requirements and the need to minimise dielectric fluid volume. The success of immersion cooling therefore depends on balancing its thermal benefits against these practical implementation challenges.
Which compatibility issues between dielectric coolant and cells, busbars, seals, adhesives, plastics and coatings become critical over ten or more years of battery life?
Long-term material compatibility is crucial for the successful implementation of immersion cooling. As battery architectures become increasingly integrated, structural adhesives and sealants play a crucial role in system integrity. Any interaction between these materials and the dielectric fluid must remain stable over the entire service life of the vehicle.
Achieving this requires a holistic approach that considers fluid selection, material compatibility and joint design from the earliest development stages. Close collaboration between battery developers, material suppliers and dielectric-fluid manufacturers is essential to establish robust and durable solutions.
Given the conference focus on thermal runaway and fire protection, can immersion cooling materially suppress propagation, or does it mainly shift the challenge towards gas release, coolant contamination and pressure management?
Immersion cooling is highly effective in suppressing propagation because it dissipates heat rapidly while significantly reducing direct cell-to-cell heat transfer during a failure event.
Which other agenda topic intersects most with your own, and what would you ask that speaker or panel?
Being part of the German battery industry and working on technologies that can significantly enhance battery performance, I am particularly interested in the panel discussion “Quo Vadis Battery Industry in Germany?”
Beyond the essential topics of safety, cost competitiveness and industrial scale, I would like to hear the panel’s perspective on the unique value proposition of a European, and specifically German, battery ecosystem.
My question would be: Which capabilities can Europe realistically differentiate itself through over the next decade, and how can OEMs, battery suppliers and research institutions collaborate to turn those strengths into a sustainable competitive advantage?
