E-Mobility Engineering | January/February 2024 17 Tony Persson | In conversation and which should be outsourced.” For instance, given the particular skill sets, knowledge and large-scale processes needed to create battery cells, Scania has opted not to research or produce these in-house. Instead it utilises cells from Northvolt, whose head office, laboratories and design facility are conveniently near to Scania’s battery factory in Södertälje. “By comparison, the processes and skills needed for assembly of battery modules and packs are the same or closely linked in many ways to those already utilised in Scania’s manufacturing centres,” Persson says. “Our design department meanwhile focuses most of their work on optimising and simulating the designs of our modules and packs, but also does some work in designing cells for our use in partnership with Northvolt’s design department.” For heavy EVs such as those being designed by Scania, Northvolt manufactures and supplies a cell designed with an NMC cathode and in a prismatic format. This is identical to that used in the Audi-Porsche Premium Platform Electric (PPE) modular skateboard powertrain (that system being detailed further in our cover story on p.20). “The chemistry has been specifically tailored for the endurance and lifetime requirements of heavy vehicles – trucks and buses, specifically – such as meeting a lifetime expectancy of 1.5 million kilometres’ worth of operations, which we regard as an outstanding parameter for Northvolt to have achieved,” Persson comments. As extra motivation for leveraging Northvolt cells in Scania’s future commercial EVs, Persson makes reference to reports that the Northvolt cell is to be the “greenest” on the market, owing to that company’s use of recycled materials in manufacturing its batteries, as well as its use of clean grid energy to power its production lines. This is thanks to partners and investors such as Vattenfall (which, as discussed in issue 18, Mar/Apr 2023, aims to supply renewable energy to e-mobility and other industries seeking to output products with zero emissions from production through to end-of-life). A couple of examples of Scania’s new generation of heavy electric vehicles have already been announced. For instance in 2019, Scania announced a battery-electric version of its Citywide city bus, which entered production in 2022. Sized for a seating capacity of 35 passengers and a total capacity of 100 persons, the Citywide BEV can integrate either 8 or 10 packs, for up to 254 kWh or 330 kWh of NMC-based energy storage. Both selections entail an estimated 320 km of range depending on driving, operational and environmental conditions (the 10 pack option likely being recommended for more energyintensive routes and locations). The Citywide BEV’s powertrain integrates an oil spray cooled electric motor built for 250 kW of continuous power and 300 kW of peak output, as well as a two-speed gearbox and a braking system combining energy recuperation with electro-pneumatic disc brakes. Additionally in 2020, the company announced the official market launch of its first battery-electric truck model when the opportunity arose to rejoin as head of battery production at the company’s new battery assembly plant at Södertälje in Stockholm County. “Since before my university days doing a Masters in Engineering at Lulea in northern Sweden, I’ve always been interested in new areas of technology, particularly when it requires working on new skills and new perspectives; so I applied for the job and I’ve been working to develop Scania’s outsourced production of energy storage systems for electrified trucks and buses ever since.” Heavy commercial EVs As many readers will already be aware, heavy commercial EVs require a number of different parameters in their battery packs compared to those in passenger cars. “For instance, the big one for us is that heavy trucks may be required to operate over 24/7 periods, rather than the regular lengthy rest or slow recharging periods that passenger cars get, between some commuting here and there for much shorter periods than those trucks or even buses work,” Persson notes. “That has an impact on the kinds of cells and other components you choose, which in turn impacts what aspects of battery production should be performed in-house EU laws state that truck drivers can drive 4.5 hours, then must take a 45 minute break; this sets Scania’s engineering targets for its truck battery packs’ endurance and charging times
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