E-Mobility Engineering 017 l ECE Doosan electric excavators dossier l In Conversation: Matt Faulks l Battery testing focus l Battery Show North America 2022 report l Ariel Hipercar digest l Cathode materials insight l Thermal management focus

high ambient temperatures. Taken together, all of this means that the thermal management systems architecture can be even more complex than in battery EVs. Fuel cell management The main thermal challenge with fuel cells, according to the fluids specialist, is maintaining a constant operating temperature for the polymer exchange membranes to operate at peak efficiency. He explains that the cooling medium is deionised water, which is used because the membranes are very sensitive to ‘poisoning’ by the ions in tap water, for example, and to the degradation of metals in contact with it. Deionised water is a relatively corrosive liquid, so careful selection of compatible materials during systems design is essential. In addition, the plates need uniform cooling if they are to be efficient and durable. Materials issues The move towards higher power and energy densities in EVs also affects the development of thermal interface materials, compression pads, encapsulants, gap fillers and adhesives used in the powertrain’s subsystems. The need for heat transfer across the interface between surfaces in particular has grown, and it is becoming more important to ensure rapid and efficient removal of heat from more thermally sensitive components such as cells, power switch substrates, magnetics, passive components and the insulation of motor windings. The first materials specialist emphasises the importance of smart design, regardless of the material involved, to optimise weight and cost. Materials dispensed in liquid form, such as gap fillers and potting compounds, dominate assembly processes, while the use of pads as the primary certified isolation is undergoing something of a renaissance in powertrain systems. “Selecting the right product together with the proper process should drive the final decision, because there The suitability for automated manufacturing of processes such as applying adhesives to cooling plates should be considered early on in a thermal management system design (Courtesy of Parker Lord) January/February 2023 | E-Mobility Engineering