Hub-Motoring in Lordstown’s Novel Endurance
The pioneering full-size electric pickup features four in-wheel electric motors and is engineered for fleet customers.
“It’s been exciting to create a new vehicle from the ground up,” Chi Yip, Lordstown Motors’ director of vehicle integration, asserted from the passenger seat, as we accelerated onto I-94. Our vehicle, a new Endurance electric all-wheel-drive pickup, was VIN 006, the sixth production unit out of the company’s eastern Ohio plant. It’s the first significant production vehicle to feature electric hub motors in all four wheels. And like every Endurance, our test-drive truck was painted white.
Yip is a veteran vehicle-dynamics engineer with extensive experience at Meritor, Ford, and an Asian EV start-up before joining Lordstown Motors three years ago. He’s based at the company’s Farmington Hills, Mich., engineering office and was heavily involved in the truck’s clean sheet ‘skateboard’ development.
“The challenge on this program has been in balancing the key vehicle attributes— performance, towing capability, grade ability, 0-to-60 mph acceleration, and meeting our energy efficiency goals,” Yip said. “We don’t have many options available compared with the other full-size pickups. Fleet buyers heading into the EV space are focused on vehicle durability, reliability, utility and low cost of ownership,” he noted.
From the driver’s seat, the four-door Endurance comes across as spot-on for its target market’s expectations. It’s aimed at fleet customers, not the general public; the cabin is thus trimmed as a workplace, not a leather-goods showcase. The multi-adjustable driver’s seat is plenty supportive and both legroom and the foot box are more than ample for my 6-ft. 3-in. frame. Cabin noise at highway speeds is impressively low.
“We put a lot of work into seat comfort and durability,” Yip explained. “We spec’d a new fabric that’s waterproof and easy to clean. It’s not the typical work-truck vinyl, which fleet-vehicle drivers told us is uncomfortable.”
In terms of performance, the Endurance’s 47-ft. (14.3 m) turning radius impressed me while still negotiating the parking lot — a benefit of the in-wheel drive system, according to Yip. It will be a benefit in tight urban delivery and service situations.
Lordstown Motors claims the 6500-lb (2948 kg) Endurance will accelerate from stop to 60 mph (96.5 km/h) in 6.3 seconds, which to my seat-of-pants during our test drive (during North American Truck of the Year evaluation) feels about right. The Ford F-150 Lightning is more than two seconds quicker, according to Car and Driver, but that metric isn’t a priority to fleet users.
Lordstown claims a 118-mph (190 kmn/h) top speed, but an app designed for fleet managers allows them to cap vehicle acceleration and max velocity (realistically 80mph/129 km/h) in order to conserve battery energy for most use cases. The app also “provides the manager with a lot of data, including road speed, miles traveled, and service info,” Yip noted.
With the propulsion system underfloor and at the wheels, the Endurance has a ‘frunk’ (front trunk) lockable storage well offering 9.6 cu.ft. (279 L) of space underhood. The composite cargo bed, also made in-house, will hold 59.3 cu.ft.(1671 L). Payload rating is 1,050 lb (476 kg), and the Endurance is capable of towing up to 8000 lb (3629 kg).
Wheel motor matters
The in-wheel hub radial-flux, 3-phase AC synchronous L1500 motors, designed by Slovenia-based Elaphe, deliver instantaneous torque directly to the tire contact patch without the delay and backlash typical of a driveshaft/halfshaft layout, Yip explained. The Endurance in-hub motors generate 1500 Nm (1106 lb-ft) peak, 650 Nm (479 lb-ft) continuous at 1480 rpm, according to Elaphe. Power is rated at 440 hp (328 kW). The hub motors operate on 370V nominal, provided by a 109-kWh battery pack that uses LG Chem lithium-ion cells. Lordstown Motors manufactures the hub motors in-house under license from Elaphe.
A DC fast charger will replenish electrons, from 20% state of charge to 80% SoC, in 45 minutes, Yip said. The Endurance is capable of 200 miles’ (321 km) range in moderate average temperatures.
Each wheel module weighs roughly 34 kg (75 lb); unsprung mass is the long-argued downside of hub-motor technology. (See July 2021: Making the Case for In-Wheel Motors) “During chassis development we found that because of the battery packs, the vehicle’s actual sprung mass is quite heavy. So, the sprung-mass-to-unsprung mass ratio isn’t much different from that of a normal pickup,” Yip said. “From a tuning standpoint we didn’t have too many problems in establishing and achieving our ride, handling and steering targets.”
Lordstown Motors is betting that fleet customers will be attracted to their EV’s value equation: longer service intervals compared with ICE-powered pickups, including less frequent brake pad/rotor replacement due to the regen. There are no driveshafts, CV joints and CV boots to replace.
The plan is for the Endurance (base price $65,000 as of November 2022) to be a multi-hundred-thousand-mile proposition for fleet owners, Yip confirmed. He acknowledged that the in-hub motor modules are “a new technology that does require some service, such as seal replacement” and that the company will provide service training.