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

an even cooling distribution. You want to maintain cell temperatures within very tight tolerances, to optimise performance and avoid battery degradation.” The company designs, develops and manufactures thermal management system components for electric, hybrid and IC powertrains. A recent example is a tubular coolant manifold for a truck OEM, manufactured from 0.7 mm-thick stainless steel. The original customer specification was for a mild steel part coated to protect it from corrosion, but the development process revealed that the part would be more cost-effective if it were manufactured from more expensive stainless steel, as the coating and its application process made the mild steel part costlier overall. The company also makes heat sinks for power electronics using copper or aluminium, with copper preferred for high-performance applications. One example is designed to cool the IGBT board in a power converter, and features patented fins shaped like the Greek letter omega, a configuration well-suited to rapid charging applications because it limits the temperature increase more effectively. Fuel cell-based propulsion systems are the focus of intensive development to replace diesels in heavy truck applications, and their thermal management needs bring their own set of problems. The automotive powertrain specialist notes that although a fuel cell-based drive is more efficient than a comparable diesel powertrain, most of the waste heat goes directly into the coolant. A further complicating factor is that the resulting coolant temperature is lower, so the cooling system has to work harder to reject an equivalent amount of heat energy. “We are talking about a factor of 1.5 to 2 for the required cooling capacity compared with the combustion engine,” he says. What’s more, he says, the optimum temperature for a fuel cell is around 70 ºC, which is particularly challenging in materials, such as silicon carbide, thermal management systems will need to be designed with high heat flux in mind,” he says. “Simulation tools can help reduce the development time by modelling how the coolant is distributed.” He points out that his company’s cooler designs can have components soldered directly onto them, eliminating the need for thermal interface materials and the associated thermal resistance. “We achieve this by offering direct- bondable aluminium designs featuring a thin layer of copper,” he says. The design of cooling plates and heat sinks is also evolving, and is an area in which metals still have a lot to offer. That is particularly so when the volume available for them in a battery pack or module enclosure is at a premium, according to experts from a Tier 1 thermal management systems supplier with a long history in the automotive industry. The company primarily designs thermal management and fluid conveyance solutions, and has developed liquid- cooled battery cooling plates, some of which are up to 2 m long, using various materials and manufacturing methods. A recent thermal management system developed for a passenger car application, which is now moving into series production, features two formed aluminium plates brazed into a single assembly, on which battery modules are placed. This solution maximises design flexibility, coolant control and battery performance, the experts say. “The temperature differential between the hottest and the coldest cells can be as low as 1 ºC, so we are getting good performance out of this design,” one of the experts says. “It is essential to have Some suppliers of thermal management equipment Complete systems Dana +1 450 645 1444 www.dana.com Mahle +49 711 501 0 www.mahle.com Webasto +49 898 579 40 www.webasto.com Heat exchangers and related components Bosch +91 80 6145 5995 www.bosch.com Senior Flexonics +44 1495 241 500 www.seniorflexonics.com Thermal fluids 3M +1 651 733 1110 www.3m.com Castrol BP +44 1932 775 644 www.castrol.com Engineered Fluids +1 281 205 0162 www.engineeredfluids.com Thermal interface materials, adhesives, gap fillers and coatings AkzoNobel +31 88 969 7809 www.akzonobel.com Aspen Aerogels +1 508 691 1111 www.aerogel.com Axalta Coating Systems +44 1684 273 040 www.axalta.com Bdtronic +49 7934 1040 www.bdtronic.com DuPont +44 1438 734 000 www.dupont.com Elantas +49 40 789460 www.elantas.com Henkel +1 800 562 8483 www.henkel-adhesives.com Kerafol +49 9645 88300 www.kerafol.com Morgan Advanced Materials +44 1753 837 000 www.morganadvancedmaterials.com Neograf +1 216 529 3777 www.neograf.com Parker Lord +1 877 275 5673 www.lord.com Scheugenpflug +49 9445 9564 0 www.scheugenpflug-dispensing.com Viscotec +49 8631 92740 www.viscotec.de Voss Automotive +49 2267 630 www.voss-automotive.net Wevo-Chemie +49 711 167610 www.wevo-chemie.de Dielectric coolants such as Castrol’s ON EV thermal management fluid have proved effective in preventing propagation after a cell enters runaway (Courtesy of Castrol BP) 70 January/February 2023 | E-Mobility Engineering