Shell and FAW Test Immersion-Cooled Battery for Hybrid Trucks
Concept battery pack claims 98% gradability gain and 32% longer life, but production timeline remains unannounced.
Shell and FAW Trucks tested a battery pack that submerges cells in electrically insulating fluid to manage heat. The companies claim the immersion-cooled design improved gradability by up to 98%, vehicle-level energy efficiency by 0.8%, and battery life by up to 32% under specific test conditions. The battery pack is installed in the Shell Starship 3.0 Hybrid concept truck, not a production vehicle.
How does immersion cooling differ from conventional battery cooling?
Conventional battery packs cool cells from the bottom using a cooling plate or separate system. Immersion cooling surrounds the cells with fluid that contacts them directly, transferring heat away from a larger surface area. Shell says this approach maintains more consistent temperatures across the pack during high-power charging and discharging, which generates the most heat.
The fluid is electrically insulating, so it does not short the cells. Heat moves into the fluid, which is then circulated through a heat exchanger. The design targets commercial vehicles that place sustained high-power demands on batteries during acceleration, heavy loads, and fast charging.
What performance gains did Shell and FAW measure?
The 98% gradability increase means the truck can climb steeper grades under battery power. The 0.8% efficiency gain is vehicle-level, not cell-level. The 32% battery-life improvement is a projection based on thermal modeling and accelerated testing, not field data from production fleets.
The China Automotive Technology and Research Center verified the test results. Shell and FAW conducted the testing under specific conditions on the Starship 3.0 Hybrid concept vehicle. Shell said final performance data will be released after the validation process is completed.
Is this battery pack going into production?
No production announcement has been made. Shell and FAW are evaluating the battery pack for potential use in future FAW hybrid commercial vehicles. The companies will display the Starship 3.0 Hybrid with the immersion-cooled pack at the FAW Trucks booth during IAA Transportation 2026 in Hannover, Germany, starting September 14.
FAW Trucks is a majority-owned subsidiary of China FAW Group, headquartered in Changchun, China. Shell contributes thermal-management fluids and lubricants expertise. FAW provides commercial vehicle engineering.
What are the serviceability and cost unknowns?
Shell has not disclosed the fluid type, replacement interval, or cost per gallon. Immersion-cooled battery packs require fluid changes and leak monitoring. If a cell fails, the entire pack may need draining to access the failed module, adding labor hours compared to a plate-cooled design where modules can be swapped without fluid handling.
No warranty terms, fluid-service costs, or parts availability have been announced. The technology remains in the validation stage. Whether the performance seen in the concept truck translates to a production hybrid system suitable for commercial fleets has not been determined.
Why does thermal management matter for commercial vehicle batteries?
Batteries generate heat during charging and discharging. High temperatures degrade cells faster, reducing cycle life. Uneven temperatures across a pack cause some cells to age faster than others, limiting total pack capacity as the weakest cells set the floor.
Commercial vehicles place higher sustained power demands on batteries than passenger cars. A truck climbing a grade at gross weight or fast-charging between shifts generates more heat than a commuter EV. Better thermal management allows manufacturers to increase power output and charging speed without shortening battery life.
Immersion cooling is one approach. Other manufacturers use liquid-cooled plates, refrigerant loops, or air cooling. Each has tradeoffs in cost, complexity, and thermal performance.
What does this mean for fleets considering hybrid trucks?
The Shell and FAW battery pack is not available for purchase. It is a concept system being validated for potential future use. Fleets cannot spec it on a truck order today.
If the technology reaches production, the key questions will be upfront cost delta versus a conventional battery pack, fluid-service interval and cost, warranty coverage for thermal-management components, and field data from commercial fleets running the system under real-world duty cycles. Test-track results do not predict total cost of ownership until parts pricing, service procedures, and failure modes are known.
Fleets evaluating hybrid or electric trucks should focus on production systems with published warranty terms, parts availability, and service networks. Concept vehicles demonstrate what is possible under controlled conditions. Production vehicles reveal what works at scale.
