Next-Generation Thermal Management - Immersive Cooling and Heat Pump System

Automotive IQ: Kamel, can you start by telling us a bit about yourself and your role at Valeo?

Kamel: I’m Dr. Kamel Azzouz, the Head of Research & Innovation and Master Expert in Thermodynamics and Heat Transfer at Valeo Power. My focus is on developing the next-generation of thermal technologies for electric mobility, covering areas like battery cooling, immersive dielectric systems, advanced heat pumps, and global energy management architectures that enhance efficiency, safety, and sustainability. In parallel, I serve as an Associate Professor at the Arts et Métiers Institute of Technology in Paris, which allows me to bridge the gap between pioneering academic research and real-world industrial application. Across both industry and academia, my goal is to push the boundaries of thermal efficiency, and innovation to help shape the next generation of clean, safe, and intelligent electric vehicles.

Automotive IQ: Immersive cooling has been gaining attention in recent years. From your perspective, where do we currently stand in terms of real-world adoption?

Kamel: We have clearly moved out of the research phase and into a serious transition. Immersive cooling is now a tangible reality, with several major OEMs actively testing and validating full-scale battery packs using dielectric fluids. While high-performance vehicles, such as the Mercedes AMG ONE, have shown potential and the next step is scaling this technology across wider vehicle segments. We expect larger production programs once cost targets are met for these segments. 

Automotive IQ: What developments, whether in materials, system integration, or regulatory frameworks, do you think are most critical to unlocking the full potential of immersive cooling in the coming years?

Kamel: The key areas are: fluid, pack design, sealing, and standardisation.

Fluid: We need dielectric fluids engineered for lifetime reliability, stable in dielectric strength, viscosity, and thermal performance, and fully compatible with all materials inside the pack, including the cells themselves. At the same time, the fluid must remain cost-effective to enable large-scale adoption across different vehicle segments.

Pack design must ensure homogeneous flow and manage cell swelling over time. We use elastic compression systems and venting valves specifically designed for dielectric fluids to equalise pressure and ensure safety.

Sealing: the system must remain 100 % fluid-tight over 15-20 years, with validated joints, welds, and interfaces that resist pressure and thermal cycling.

Standardisation is essential. Common OEM qualification methods for dielectric stability, safety, and material ageing will speed up validation and give everyone more confidence in adopting this technology.

Automotive IQ: What are the biggest challenges in scaling immersive cooling systems, especially around system design, safety, cost, and maintenance?

Kamel: The main challenge is managing the transition from conventional water-glycol systems to immersive dielectric cooling, which requires new design standards, validation methods, and service procedures.

At Valeo, we address this with our compact, modular “fill-for-life” immersive technology designed to meet all safety, performance, and integration requirements.

The next step is not just in the hardware but in the process: we need to standardise validation and maintenance protocols and clearly demonstrate to OEMs that this technology delivers an excellent weight–cost–performance balance, fully aligned with future EV efficiency targets.

Automotive IQ: When developing next-generation heat pump systems, how do you balance the three key pillars: safety, performance, and sustainability?

Kamel: It starts with going back to basics, simplifying the system.

Safety: We prioritise safety by design. Eliminating unnecessary interfaces and connections reduces potential leak points, which is crucial when integrating low-GWP natural refrigerants like R290. We use compact circuits and highly reliable components to minimise refrigerant charge and ensure leak-tightness.

Performance: Simplification also drives performance. Fewer connections mean lower pressure drops, maximising efficiency with less compressor power. We use optimised, multifunctional heat exchangers that combine several operations into one compact module.

Sustainability: This is anchored by using natural refrigerants and recyclable materials, combined with architectures designed for comprehensive waste heat recovery from the battery and e-motor. This holistic approach enhances both operating efficiency and overall environmental impact.

Automotive IQ: Sustainability is an increasingly important focus. What role do refrigerants, system materials, or lifecycle considerations play in making heat pump systems more environmentally friendly?

Kamel: Sustainability is a full lifecycle commitment starting with the choice of refrigerant. We’re moving toward natural, low-GWP fluids like R290, which offer excellent thermodynamic performance with minimal environmental impact. But sustainability also depends on the  heat-transfer fluids used in the cooling loops. New low-carbon, and in some cases  carbon-negative dielectric fluids are now enabling single-fluid architectures that can cool the battery, e-motor, and power electronics using the same medium.

This approach simplifies the system, reduces the number of components and interfaces, and enables efficient energy recovery strategies through the heat pump, directly lowering energy consumption and carbon footprint. We combine this with recyclable, PFAS-free materials and compact designs that are built for leak-tightness and easy end-of-life servicing. Altogether, these advances make the next generation of thermal systems safer, more efficient, and truly sustainable, both in operation and across the full lifecycle.

Automotive IQ: Looking ahead 5 to 10 years, what do you believe will be the biggest driver of innovation in heat pump systems, regulations, cost pressures, advances in materials science, or something else?

Kamel: In the next decade, innovation will be driven by regulations, cost efficiency, performance and smart system integration. Regulations will accelerate the move toward natural refrigerants and PFAS-free materials, while cost pressure will push for simpler, modular, and multifunctional designs. We’ll see more smart subcomponents - such as multifunctional heat exchangers and intelligent multiway valves - that combine several functions in a single, compact module. This reduces connections, leak points, and overall system complexity. AI-based control and predictive thermal management will make these systems smarter; continuously optimising comfort, range, and efficiency in real time.

Another major driver will be the evolution of battery chemistry. The arrival of solid-state and sulfide-based cells, capable of very high C-rates, will create new thermal challenges, higher-capacity cooling and heating systems. This will drive even closer integration between the heat pump and the battery pack, where the same architecture can extract, store, and reuse energy with minimal losses.

About Kamel: Kamel Azzouz is an Associate Professor at the Arts et Métiers Institute of Technology in Paris, specializing in thermal energy transport, storage, and conversion. He holds a PhD in Thermal Sciences and is a Mechanical Engineer . He is also a graduate of Stanford University in Innovation and Technology Management. Currently, he is the Head of Research and Innovation and Master Expert in Thermodynamics and Heat Transfer at Valeo, where he leads the development of advanced thermal systems—including battery cooling, heat exchangers, heat pumps, immersive cooling technologies, and global energy management strategies. Prior to joining Valeo, he served as a Senior Expert at the French Environment and Energy Management Agency (ADEME). He is the author of over 876 patents and 86 international publications, and has chaired several international conferences in the automotive sector.