E-Mobility Engineering 016 l Aurora Powertrains eSled dossier l In Conversation: Thomas de Lange l Automated manufacturing focus l Torque sensing insight l Battery Show Europe 2022 report l Sodium batteries insight l User interfaces focus

Autioniemi adds, “Using cylindrical cells would have meant too many air gaps between each cell. You can fit them together as tightly as you can but there’s always going to be more unused space compared with pouch cells. “And while we’re monitoring the market for new battery chemistries, and see things like LFP gaining traction, we’re after what’s most available in great quantities at this moment. That’s as important as energy with the team stating that the same energy density would not have been possible with cylindrical or prismatic cells, as was tried with the earlier pack prototypes. “Thermal management also played a big part in choosing pouch cells,” Haaviko explains. “When we have high C-rates we need a high cooling throughput, and the pouch cell’s large surface area maximises its ability to thermally conduct the heat away very efficiently.” density if we want to be serious about scaling up our production, but LFP just isn’t optimal yet for either of those targets.” The BMS Considerable software development went into the BMS to ensure that the modularity – and the ability to quickly add or remove modules from each eSled’s pack – was as seamless as possible, without quite being plug and play. Some manual configuration is needed, but the company anticipates programming the BMS for automatic recognition and calibration for modules in the near future. “Disassembling and reassembling NMC battery packs means working with dangerous, high-voltage equipment,” Autioniemi points out. “You have to know what you’re doing, and it’s not something an amateur technician ought to be handling, so plug-and-play modularity isn’t totally necessary from that point of view. “It’ll be one of our on-site engineers, not one of the end-user’s technicians, who reconfigures and calibrates the battery packs when needed. Speci ications eSled Battery-electric snowmobile Dimensions: 3015 x 1283 x 1168 mm Battery: lithium nickel manganese cobalt oxide cathode Motor: axial lux permanent magnet Weight: 270 kg (at maximum battery complement) Width between ski centre lines: 1074 mm Suspension front travel: 248.57 mm Battery energy: 7 21 kWh Maximum range: 100 km Maximum power output: 60 kW Maximum speed: 130 kph Maximum torque: 140 Nm Maximum charging time: 2.5 hours on 3.3 kW AC, 1 hour on DC The modules are built around NMC pouch cells, chosen to optimise thermal management and specific energy tOrougOout tOe pack 28 Winter 2022 | E-Mobility Engineering