XD Thermal develops new battery cooling system for electric buses
XD Thermal has developed a new cooling architecture for the batteries of a European electric bus platform. The integrated system is said to require fewer components and can be adapted to different battery sizes.
Chinese thermal management specialist XD Thermal has, according to its own statements, developed a new battery cooling system for an unspecified European electric bus platform. The platform uses battery modules with a capacity of 35.3 kWh, and XD Thermal contributes liquid-cooled battery housings with stamped cover plates. This design enables heat dissipation from both sides of the battery modules.
Unlike solutions with separate cooling plates, parts of the thermal management system are directly integrated into the housing structure. According to XD Thermal, this reduces the number of components required for cooling by around 25 per cent while eliminating several assembly steps.
The configuration with multiple thermal interfaces also ensures more uniform heat distribution within the battery system, thereby contributing to the lifespan of the lithium-ion batteries. However, XD Thermal has not published specific figures on cooling performance, temperature distribution, or battery lifespan, and independent tests to verify the stated advantages are not yet available.
Integrated cooling increases demand on sealing
According to the manufacturer, integrating the cooling system into the battery housing introduces additional requirements for design and production. A central challenge was sealing the entire system. Due to multiple interfaces, joints, and sealing paths, these had to be tested not only individually but also in interaction with each other.
XD Thermal developed its own testing devices for this purpose and gradually employed air and helium leak tests. This approach was intended to detect even minor leaks before the system was approved. Another challenge involved coating the different surfaces. Depending on the area, various insulating and thermal barrier materials are used. To address this, the company developed special suspension and masking processes to apply the different coatings even to more complex geometries.
“Once cooling becomes part of the housing, the design boundary changes,” says Xu, Technical Director at XD Thermal. The focus is no longer on optimising a single cooling plate but on the thermal performance of the entire structure while ensuring suitability for series production.
Series production readiness achieved in two months
The first prototype was delivered in around six weeks, and the design reportedly reached series production readiness after about two months. According to the company, the teams for thermal management, design, processes, quality, and production worked in parallel, allowing insights from prototype construction to flow directly into further development.
The architecture is also said to be adaptable to different vehicle platforms, battery dimensions, and capacities without the need to redevelop the basic cooling concept. Since early 2025, XD Thermal has, according to its own statements, built additional production capacities for large-format battery cooling components. These are now also said to be used for further electric bus and heavy-duty projects.
For electric commercial vehicles, the integration of battery and thermal management is gaining importance, as space and weight must be used as efficiently as possible. Other suppliers are also increasingly pursuing modular or integrated approaches for components in electric commercial vehicles. Mitsubishi Heavy Industries recently unveiled a new electric transport cooling system for e-trucks, where individual components can be flexibly arranged to accommodate the limited space imposed by the traction battery.