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

Peter Donaldson talks to industry experts about the latest advances in EV thermal management technologies Heat exchangers U sers of EVs of all kinds, and battery EVs in particular, want more range and/or running time, faster charging and greater assurance of safety. Thermal management is central to all of these. An expert from an electrification specialist reports strong interest from industry customers in developing solutions that allow the heat generated by the motor and power electronics to be captured and reused for other functions, such as heating the cabin or warming the battery, which helps to reduce parasitic losses and extend range. A further trend the expert identifies is the desire to improve the volumetric efficiency of the battery by making the cooling solutions more compact. He says that by using two-sided cooling, for example, OEMs can reduce the number of cold plates required, which frees up space for additional battery capacity to increase range. Evolving cell technology could also have a major effect on thermal management, explains a specialist in thermal interface materials, adhesives and sealants. Overall, the specialist says, optimising battery pack design for higher energy density, weight and cost reduction will drive significant changes in the requirements for thermal interface materials. He points to the development of cell-to-pack and cell-to-chassis battery architectures as examples. This design approach, he argues, will bring requirements for thermally conductive adhesives that contribute to efficient thermal management and crash-relevant structural integrity. At the same time, the adhesives will have to be de-bondable on demand to address repairability and ease of recycling, as these are defined by and will become enshrined in regulations. Another thermal management materials specialist says the weight saving offered by cell-to-pack architectures is achieved by eliminating numerous steps, parts and materials when batteries no longer require module housings in addition to the main case, and individual cells are bonded directly to cooling plates. Battery manufacturers and OEMs are also looking for alternatives to silicone- based thermal management materials in some applications. Solutions based on other chemistries including urethanes, epoxies, modified silane polymers and acrylics, in addition to silicones, are therefore becoming increasingly important. An automotive powertrain specialist with long experience in IC as well as electric powertrains emphasises that the thermal differences between the two have a major impact on systems design, and are driving closer integration. “The absolute temperature in an EV’s cooling circuit is much lower than in an IC engine,” he says. “Initially that is a disadvantage for the performance of the cooling system, since the temperature gradient – the difference from the With the continued push by EV OEMs for more energy efficiency, as with Kia’s EV6 for example, advanced thermal management is essential (Courtesy of Kia) 64 January/February 2023 | E-Mobility Engineering