Earlier this yr, Rivian expanded its plant in Regular, Illinois by almost 20% to fabricate its Enduro drive unit. It’s an about-face from the drive models equipped by Bosch in Rivian’s Quad-Motor fashions, and will assist mitigate the bottlenecks to ramping manufacturing of the R1T journey pickup truck, R1S three-row SUV, and EDV electrical supply van.
Outfitted within the EDV and Rivian’s new Twin-Motor fashions, the Enduro drive unit was designed and developed in home to be extra environment friendly, cheaper, and higher insulated from provide chain shocks that quaked the trade throughout the pandemic, proper as Rivian started manufacturing in 2021.
Rivian purchased the forlorn Mitsubishi plant for $16.5 million in 2017 and now churns out each Quad Motor and Twin Motor fashions. A latest tour of the 4-million-square-foot facility showcased the 620,000-square-foot growth wanted to supply Enduro, and the way that drive unit will allow manufacturing for a cheaper R2 platform, slated to be developed at a brand new plant in Georgia as early as 2026.
For now, its Regular plant is on tempo to fabricate 52,000 Rivians this yr, with a goal of 150,000 models ultimately. Its passenger autos might be provided with both the 4 motors developed by Bosch within the Quad Motor setup or the Normalized [ahem] Twin Motor setup. Because the starting of this yr, the EDV solely makes use of the Enduro single-motor drive unit on the entrance axle.
Right here’s an summary of the Enduro drive unit and Rivian’s Twin-Motor fashions.
Rivian plant in Regular, Illinois, manufacturing its Enduro drive unit
Rivian Twin-Motor availability
Twin-Motor fashions offered with Normal, Massive, and forthcoming Max Pack battery sizes
Efficiency Twin-Motor offered with Massive and Max Packs (obtainable this fall)
Normal Pack to be made with lithium iron phosphate cells, however has no launch date
Each Quad-Motor up to now has been offered with the Massive Pack; no different pack dimension is obtainable
As of now, Rivian has solely offered the R1T and R1S as Quad-Motor fashions with the Massive Pack. Orders for the R1T Twin-Motor and Efficiency Twin-Motor with the Max Pack are open. The R1S Max Pack choice might be provided on the configurator this fall.
The Normal Pack holds probably the most promise by way of effectivity. With its LFP chemistry and the Enduro drive unit, the EDV was 35% extra environment friendly than earlier builds with the 135-kwh battery pack and the Bosch motor unit, in response to Rivian CEO RJ Scaringe. First deliveries of fashions with the Normal Pack are anticipated early in 2024.
It stays to be seen how lengthy Rivian will maintain providing the dearer Quad-Motor setup.
Rivian R1T and R1S Twin-Motor spec chart
Rivian Twin Motor pricing
R1T Twin-Motor Normal Pack $74,800, together with $1,800 vacation spot
R1T Twin-Motor Massive Pack provides $6,000 to $80,800
R1T Twin-Motor Max Pack prices $16,000 extra to $90,800
Efficiency Twin-Motor Massive Pack provides $5,000 to $85,800
Efficiency Twin-Motor Max Pack prices $95,800
R1T Quad-Motor Massive Pack prices $88,800
The Max Pack improve represents the largest soar in Rivian’s pricing construction, at $16,000. That makes each the Twin-Motor and Efficiency Twin-Motor dearer than the Quad Motor.
The R1S three-row SUV is $5,000 extra throughout the board, however the Max Pack comes on-line within the configurator this fall.
Rivian Enduro drive unit parts
Rivian Quad-Motor vs. Twin-Motor design
Enduro Twin-Motor drive models weigh about 220 kilos
Quad-Motor rear drive unit weighs 320 kilos; Quad entrance weights 275 kilos
Enduro drive models are smaller, lighter, and extra environment friendly
The mechanical distinction between the Rivian Enduro drive unit and the Bosch unit comes right down to dimension, price, and effectivity. The Quad-Motor models home two motors and tow gear units in every unit, leading to bigger and longer casings. The rear-axle quad unit measures 135 mm lengthy, whereas the entrance measures 110 mm lengthy, in response to Mason Verbridge, Rivian’s principal drive unit engineer. With mounts and excessive voltage cables, the rear-axle quad unit weighs about 320 kilos, and about 275 kilos up entrance.
Against this, every Enduro unit weighs about 220 kilos. For Twin-Motor fashions that provides as much as a weight financial savings of about 155 kilos. Each pound issues, even for an R1T Twin Motor Efficiency with a curb weight of about 6,750 kilos.
“There are basic physics benefits of simply having one motor, one gearset, one principally rotating meeting,” Verbridge defined. “With a Quad you have got two gear units, two motors, all of the bearings, all of the windage losses of double that rotating meeting.”
Rivian designed and housed the inverter, motor, and gearbox in a single casing, as an alternative of separate sealed entities that get bolted collectively. Basically, there are fewer components to assemble, with much less weight and fewer redundancy.
“Fundamental philosophy is when you clear up necessities of all three subsystems then it makes every little thing a lot simpler,” he defined.
Rivian Enduro drive unit meeting
Rivian Enduro drive unit inverter parts
Rivian Enduro drive unit stator parts
Rivian Enduro rotor parts
The core good thing about creating its personal motors comes from the information of methods to program and optimize the motors from the beginning, as an alternative of setting a goal for what Rivian wished the motors to do from Bosch then adjusting it forwards and backwards to get it proper for the precise use case.
For instance, the inverters changing DC from the battery to AC for the motor differ based mostly on the axle in Twin-Motor fashions. There’s a silicon carbide energy module for the entrance unit inverter however a less-expensive silicon energy module for the rear inverter. Silicon carbide has an effectivity of greater than 99% in comparison with about 98% effectivity with silicon, in response to Silva Hiti, Rivian senior director of electrical energy conversion. At peak effectivity, Hiti stated this interprets to three.5% extra vary than if Rivian used silicon energy modules for each inverters. It makes extra sense to make use of extra environment friendly (however dearer) silicon carbide on the entrance unit that’s used extra in Twin-Motor fashions.
“By the point we got here to Enduro we understood these use circumstances tremendous effectively,” Verbridge stated. “If you realize precisely what the motor must do, you realize the place you’ll be able to actually dial in and prioritize being environment friendly in these areas on that working map.”
Rivian plant in Regular, Illinois, manufacturing its Enduro drive unit
Rivian Quad-Motor vs. Twin-Motor drive modes
Each Rivian passenger automobile has All-Function, Snow, All-Terrain, and Towing modes
Efficiency Twin-Motor provides Sport mode
Quad-Motor fashions add Preserve in addition to All-Terrain sub-modes, corresponding to Drift, Rally, Rock Crawl, Smooth Sand
In contrast to the Quad-Motor setup, the Rivian Twin-Motor doesn’t have a Preserve mode. As an alternative, the default All-Function mode decouples the rear axle to run as a front-wheel-drive truck for higher effectivity in most eventualities. However the rear axle powers on-demand as effectively, not simply with a button push. So if the motive force flooring it, the torque bias can shift from 100/0 to about 45/55 in a blink.
All-Function within the Quad-Motor stays related, except Preserve mode is chosen. So the default All-Function mode within the Twin serves the same perform as Preserve within the Quad as probably the most environment friendly setting, limiting parasitic losses. Rivian wouldn’t say if all that torque on the entrance axle of the Efficiency Twin-Motor will chew by tires as excessively as Preserve mode does within the Quad, however it shouldn’t be as dramatic.
The Enduro closing drive ratio is decrease than the Quad, which is 12.9:1 in any respect 4 corners. The Twin-Motor has a closing gear ratio of 11.04:1 within the entrance and 13.7:1 within the rear. Because it disconnects the rear axle and doesn’t have the additional surge of energy from Sport mode—in most driving eventualities besides when flooring it—there shouldn’t be as a lot uneven put on on the tires as there’s in Preserve mode within the Quad.
Then there’s Sport mode within the Efficiency Twin-Motor. See extra beneath.
Rivian plant in Regular, Illinois, manufacturing its Enduro drive unit
Rivian Twin-Motor efficiency
R1T Twin-Motor makes 533 hp, 610 lb-ft of torque; it hits 60 mph in 4.5 seconds
R1T Efficiency Twin-Motor makes 665 hp, 829 lb-ft; it hits 60 mph in 3.5 seconds
R1T Quad-Motor makes 835 hp, 908 lb-ft; hits 60 mph in 3.0 seconds
In back-to-back testing on an oval loop of the R1T Efficiency Twin-Motor and the R1T Quad Motor, the Efficiency Twin-Motor had a slight lag earlier than the total energy got here on, however its surge to 60 mph in 3.5 seconds was nonetheless sufficient to drop my intestine. There’s loads of energy, particularly for a automobile this dimension and form. We didn’t get to check the usual Twin-Motor. Take into account the Efficiency Twin-Motor greater than a half step to the quad.
In Sport mode, each drive models stay engaged.
In a quick off-road demo, the Twin-Motor tackled the identical obstacles with the identical competency because the Quad Motor. The larger distinction in dealing with and four-wheel drive within the Quad as an alternative of all-wheel drive within the Twin comes from how torque will get routed to the wheels. The Twin depends on brake-based torque vectoring, whereas the Quad makes use of the 4 motors to apportion torque to every wheel. It’s a greater expertise in spirited on-road driving and extra daring off-road eventualities, however the Twin is so succesful that solely in back-to-back testing does it really feel a grade decrease.
Rivian plant in Regular, Illinois, manufacturing its Enduro drive unit
Rivian plant in Regular, Illinois, manufacturing its Enduro drive unit
Rivian Quad-Motor vs. Twin-Motor towing
R1T tows as much as 11,000 kilos with both drive system
R1S tows as much as 7,700 kilos with both drive system
Count on a forty five% battery vary drop when towing, topic to many variables
Each drive methods tow the identical quantity: The R1T tows as much as 11,000 kilos; the R1S tows as much as 7,700 kilos. Towing comes commonplace with a 7-pin harness. It doesn’t have a load-distributing hitch, however Rivian says trailer sway mitigation is constructed into the software program. The brake controller prompts from the appropriate steering wheel management or within the touchscreen.
We rode alongside in an R1T Efficiency Twin-Motor towing a 9,800-pound electrical supply van on a trailer. It was enormous, looming over us, as if a cinder block could possibly be a primary mast. The pull was noticeable, as was the wobble with some wind on an overpass. Energy was plentiful, braking by no means felt taxed, however the sheer dimension of the van on the trailer was obvious all through the demo. I can’t think about another towing eventualities with that form of aero profile.
Whereas in park, it may be adjusted to the low floor clearance setting of 10.1 inches for elevated effectivity on the freeway, or stay in the usual 11.3-inch setting. Drivers may also modify the damping between Smooth and Stiff.
Rivian estimates that placing it into Tow mode will decrease the estimated vary by 45%, however there are such a lot of variables at play that it’s a guesstimate based mostly on driving profile, trailer weight, and street circumstances, amongst different issues. One among Rivian’s key benefits is how precisely it calculates estimated vary, and a pending towing replace anticipated within the subsequent two months ought to apply that accuracy to towing. It’s going to permit you to enter the trailer weight or the system will calculate the trailer weight to create completely different trailer profiles, and the vary estimates will mirror that profile and/or weight and be taught over time to supply extra correct estimates. The replace may even issue in additional traction-based eventualities by enabling drivers to tow in Off-road and Snow mode in each Quad- and Twin-Motor fashions. The replace may even activate mattress digicam angles for the R1T.
For tow mirrors, look to the aftermarket. For many different issues, Rivian seems to have it lined.
–Rivian supplied Inexperienced Automobile Reviews an evening of lodging and a manufacturing unit go to for an up-close take a look at the Enduro drive unit.