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

Rory Jackson inds out how this snowmobile overcomes the battery performance barriers to operating in cold climates Stone-cold winner I ncreasing interest in preserving the world’s Arctic regions has generated strong demand among tour companies and eco-tourists for zero-emissions snow-going vehicles. An electric snowmobile would be quieter, emissions-free, and far easier to maintain than an IC-engined version. Unfortunately though, batteries and other electric systems suffer dramatic losses of performance in extremely cold climates. The degree of thermal management and engineering needed is so great and complicated in fact that some leading EV experts believe snowmobiles could be the most difficult vehicles in the world to electrify. Undaunted by these challenges, Finland-based Aurora Powertrains has recently unveiled its newest all- electric eSled, the seeds of which were planted in 2009 at the Lapland University of Applied Sciences (Lapland UAS). Thirteen years of research and 5 years of successful commercial activity have gone into optimising the eSled for speeding through the Earth’s coldest temperatures at up to 130 kph, running on a lithium-ion battery pack of up to 21 kWh, and tackling ranges of up to 100 km between charges. History of the eSled Research for the eSled began as part of a publicly funded r&d project at Lapland UAS, in Rovaniemi. Quick assembly of a simple proof-of-concept prototype convinced the Finnish government of the tangible potential the project held. “After that, we essentially started again from scratch, with fresh research into electrification, related standards and component distributors,” CEO and founder Matti Autioniemi recounts. The subsequent prototypes ran on lead-acid batteries, simply to get the snowmobile moving so that the drivetrain and other components could be tested. Naturally, however, a lot of r&d into superior battery technology followed, as the lead-acid batteries were good for no more than a few kilometres at a time. Once the team agreed on lithium battery suppliers, new prototypes followed, with different eSleds using different suppliers’ batteries to benchmark the performance of each one. These new snowmobiles also underwent intensive cold climate testing, in the university’s testing chambers and sometimes simply by stepping outdoors into the -40 ºC Lapland winter. “The electric motors, inverters and batteries were also being run and characterised extensively in the university’s dynamometer at the time,” Autioniemi adds. “Lapland UAS has a lot of equipment for developing and testing powertrain systems so we used them wherever we could.” Based on the results of all this r&d, the researchers steadily optimised a fleet of test vehicles, which in 2011 they loaned to a local guided tour company to gather real-world data and user feedback from their intended commercial use. Following further r&d, Lapland UAS sent its team to the SAE Clean Aurora Powertrains is one of very few companies in the world to successfully engineer and commercialise an electric snowmobile (Images courtesy of Aurora Powertrains) 20 Winter 2022 | E-Mobility Engineering