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DucRider

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Like I said earlier, I suspect the discharge is a typo or mistake.
73.55 kWh used and 146.9 kWh to recharge just ain't gonna happen, so there is an error somewhere.

Just speculation, but it could be that the data from one of the drive unit current clamps was left out of the consumption number

The limited discharge aligns with the really low mileage though, so I'm wondering if the recharge isn't the typo.
The test is a depletion test from a full charge. Recharge info is consistent with that. They would have had to completely blow the test procedures by either not charging fully or stopping the test before the battery was empty. I find either of these a much less likely explanation.
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Cold weather knocks range, but in my Model 3, snow takes it to the absurde.

Here is a drive I logged during a snowstorm last winter. The roads were covered in 2-4 inches of fresh (all 2-4" had fallen within the last hour) snow.

Consumption was a massive 813 wh/mile. At that level of consumption, my 310 miles of EPA range was only actually good for around 90 miles in the snow.

Screenshot 2021-09-28 2.42.31 PM.png


Note it was 16F at the time. My average consumption 16F weather is around 350 wh/mile. So the snow more than doubled the already elevated cold weather consumption.

Screenshot 2021-09-28 2.40.14 PM.png
DAMN, that's significant.
 

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All of the Cold weather data is for the CITY (UDDS) portion only
No data is available for hwy or the combined rating.

City 20 degrees - Conserve mode - adjusted range = 259 (actual test result = 357)
City 70 degrees - Conserve mode - adjusted range = 355 (actual test result = 491)
Where are you seeing the adjusted range? I see the 357.28, but can't find the adjusted.
 
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Major takeaways (from Rivian EPA application docs):
  1. Confirmed 108s pack architecture using 5A (nominal) 21700 cells. Modules are 8p yielding 40A ea. Nominal voltage of 400, max charging voltage of ~450V.
  2. DCFC Max of 210 kW
  3. Testing done in conserve and sport mode (then averaged)
  4. Conserve mode absolutely disconnects rear motors
  5. Tesla method of brake pedal only engages friction brakes. Blended braking mapped to the accelerator pedal if brake hold enabled. Since the accelerator should be lifted when braking, using max regen mode will recovery the most energy when using the brake pedal.
  6. Cold weather looks to be a ~40% range hit
  7. Useable battery kWh appears to be ~129
From the docs:
  • Every vehicle which is covered by this application conforms to US EPA Federal Tier 3 Bin 0 regulations applicable to new Medium Duty Passenger Vehicles and state of California ZEV regulations applicable to new Medium-Duty Vehicles for the 2022 Model Year.
  • Maintenance schedule:
    1632852921609.png
  • 4 motors, full torque vectoring capability with 1 motor/gearset per wheel. Drive units are packaged inboard, with priority on maximizing half shaft length to each wheel to enable maximum durability and suspension articulation.
  • Front and rear drive units have high level of commonality. The motor, gearbox, and inverter are sub assembled into a drive unit to optimize mass, cost, and package spacing. The motors are the largest part of the drive unit, and the drive unit orientation in vehicle is adjusted to have the motors as low and towards the center of the vehicle as possible, reducing the center of gravity and the vehicle's polar moment of inertia.
  • Interior permanent magnet motors and water jacket cooled stator. Motor air space is a sealed "air cavity" that is shared with the Dual Power Inverter Module, DPIM.
  • Fully automatic, 2 stage, single speed reduction gearset for each wheel. Left and right gearsets share oil and a common cavity for a given drive unit. The gearsets share many parts and utilize a 12.6:1 ratio on the front and rear drive units.
  • Inverters: Front drive units are silicon carbide, while rear drive units are silicone based IGBT's. All drive units share a single capacitor for 2 motors which reduces cost, mass, and package space.
  • Drivetrain: Ball spline half-shafts are utilized to maximize half-shaft durability, efficiency, and torque capacity during high articulation suspension events. On the rear drive unit, a modular disconnect is utilized to decouple the half-shaft from the output gears such that the vehicle can operate in FWD. This allows a significant range improvement during low power output and steady state cruise driving events.
  • Battery
    • The Battery pack consists of 7,776 lithium-ion battery cells which are arranged in 9 cell modules. The 9 cell modules are assembled into a fully sealed enclosure built from an aluminum frame structure. The lid includes a removable service access panel, and the bottom plate provides protection from ground strikes consistent with the vehicle’s on and off-road capability. Liquid coolant is distributed in parallel to each cell module via the coolant manifold. A Battery Management System (BMS) communicates battery operation with other vehicle systems, controls the contactors, and monitors current, voltage, and isolation measurements. The BMS also monitors sensors for detection of gases, water, and bottom plate puncture.
    • Battery pack nominal capacity is 360 Ah based on a constant current C/5 discharge rate.
    • The thermal management system for the high voltage battery is a liquid coolant system. A pump circulates coolant thru the battery and a refrigerant-cooled chiller to extract heat and lower the temperature of the battery. In cold weather, an in-line heating element is used to heat the coolant to raise the temperature of the battery.
    • Battery management control system is programmed to prevent a state of under-voltage or over-voltage per the voltage limits defined by Rivian. Contactor opens and DTCs are set when voltage of the 9 module 135 kWh battery is below 216 V or above 459 V.
  • Regenerative Braking System
    • The regenerative braking system can use up to all 4 electric propulsion motors to convert the vehicles kinetic energy to electrical energy which is stored in the vehicles high voltage battery.
    • The regenerative control logic uses two main inputs, acceleration pedal position and vehicle speed to determine a desired regenerative braking torque. The requested braking torque is then distributed between the front and rear axles based on the vehicle state, axle disconnect status, and calculated normal force on each axle. The regenerative torque is limited when the vehicle experiences low wheel traction events (e.g. ice or snow).
    • The percentage of braking performed on road by each axle is constantly changing and redistributing. It is based on the driver demanded torque and has been optimized for vehicle dynamics and range attributes.
  • Overlap of friction brakes and regenerative braking
    One pedal driving is the default, in this mode, fully releasing the pedal yields the maximum regen level. And about halfway through the pedal travel is the neutral point, where regen is limited. As the driver manually increases primary service brake pressure and friction braking torque, the vehicle regen level will proportionally ramp down to 0 Nm based on the driver braking pressure. The ramp profile is affected by many factors. When autohold is active and the vehicle approaches standstill, the braking torque will blend from motors to friction brakes.
  • Charging:
    • AC Level 1 Charging at 120 V / 12 A
    • AC Level 2 Charging at 240 V / 48 A
    • DC Fast Charging at up to 210 kW
  • Range:
    • Tested in both Conserve and Sport modes, then averaged
    • Difference of ~12% (Slightly less impact on the hwy vs city) between the modes - Conserve Mode should get you +6% range, Sport -6%
    • Cold Weather (20 degrees F) phase (performed on the City cycle only):
      Conserve mode = -27%
      Sport Mode = -57%
      Average cold weather (city) impact -41%
A few questions answered - more questions raised

EDIT: For those looking for the documents
https://iaspub.epa.gov/otaqpub/publist1.jsp
Select "Applications" for document type and "Rivian" for manufacturer (the others are not required), then search.
The older docs have a few more details about the trucks, the newest has all the test results.

The range/test figures above are only for the R1T. I haven't looked closely at the R1S results yet but would expect them to be similar
Excellent info, was especially happy to see the testing done in cold weather down to 20deg F.
 

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JohnVL

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I've explained earlier why Wh/mi is preferred to mi/kWh and the explanation I gave was that it is the natural unit for any computation we may wish to make. A dialogue I had here with a member a few months back came to mind. He wants to drive 27 miles on the beach and was concerned that he'd run out of battery. The potential killer here is rolling resistance. That is one of the easiest loads to compute as the force from rolling resistance is simply F = c*m*g in which c is a coefficient, m the mass of the vehicle and g the acceleration due to gravity. The R1T is massive at approximately (8500/2.2) = 3864 kg. On cement c ~ 0.01 so the force is 0.01*(8500/2.2)*9.8 and the energy required to overcome it in driving a mile is 0.01*(8500/2.2)*9.8*1603 N-m/mi = 0.01*(8500/2.2)*9.8*1603/3600 = 168.6 Wh/mi. From the EPA data we have 480 Wh/mi from the wall as the rated consumption which, with an assumed charger efficiency of 91% translates to 437 Wh/mi from the battery. Rolling resistance is a large part of this (38.5% of it). But this is on cement where c ~ 0.01. On sand c ~ 0.3. That's 30 times higher and implies rolling resistance will take 30*168.6 = 5058 Wh/mi!. Rolling resistance alone would deplete a 135 kWh charge in 27 miles.

Wh/mi are clearly the natural units for any computation of this sort so i suppose we would say that anyone wishing to do computations of this sort would naturally prefer wh/mi.

A lot of us like to keep track of how we are doing in our driving, understand why we did better or worse on a particular drive etc. Again Wh/mi are the natural units for the kinds of computations we do. Logging programs such as TeslaFI report Wh/mi etc and people who think about such things think in Wh/mi. We would of course prefer that the car displayed in Wh/mi but then we would, as someone else mentioned, prefer that the US used the metric system.
Your c~.3 for sand is loose sand per engineering toolbox.com. Packed sand which is what most people would drive on is c~.04-.08. It is not nearly as detrimental as you indicate. If you have ever
I've explained earlier why Wh/mi is preferred to mi/kWh and the explanation I gave was that it is the natural unit for any computation we may wish to make. A dialogue I had here with a member a few months back came to mind. He wants to drive 27 miles on the beach and was concerned that he'd run out of battery. The potential killer here is rolling resistance. That is one of the easiest loads to compute as the force from rolling resistance is simply F = c*m*g in which c is a coefficient, m the mass of the vehicle and g the acceleration due to gravity. The R1T is massive at approximately (8500/2.2) = 3864 kg. On cement c ~ 0.01 so the force is 0.01*(8500/2.2)*9.8 and the energy required to overcome it in driving a mile is 0.01*(8500/2.2)*9.8*1603 N-m/mi = 0.01*(8500/2.2)*9.8*1603/3600 = 168.6 Wh/mi. From the EPA data we have 480 Wh/mi from the wall as the rated consumption which, with an assumed charger efficiency of 91% translates to 437 Wh/mi from the battery. Rolling resistance is a large part of this (38.5% of it). But this is on cement where c ~ 0.01. On sand c ~ 0.3. That's 30 times higher and implies rolling resistance will take 30*168.6 = 5058 Wh/mi!. Rolling resistance alone would deplete a 135 kWh charge in 27 miles.

Wh/mi are clearly the natural units for any computation of this sort so i suppose we would say that anyone wishing to do computations of this sort would naturally prefer wh/mi.

A lot of us like to keep track of how we are doing in our driving, understand why we did better or worse on a particular drive etc. Again Wh/mi are the natural units for the kinds of computations we do. Logging programs such as TeslaFI report Wh/mi etc and people who think about such things think in Wh/mi. We would of course prefer that the car displayed in Wh/mi but then we would, as someone else mentioned, prefer that the US used the metric system.
0.3 is the rolling resistance of loose sand. The traction coefficient μt is 0.3 - 0.4. this is essentially a sand trap. A vehicle would need enormous tires at low pressure to navigate sand like that. If you see a car on the beach it is on hard pack sand with a c~ 0.04 - 0.08. Much closer to concrete.
 

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I'm a dummy, so please be patient with me...

Does the impact of the cold effect the range the entire time you're driving the vehicle, or just as it's "warming up"? I'm think about my specific use case in that...My garage in Denver stays somewhat warm even on cold days - say 40 degree. But, If I'm driving up to Breckenridge where it's 20 degrees or zero degrees am I going to be paying the cold penalty even though I started and got the vehicle warm prior to hitting those extreme temperatures? Or is the impact much reduced?

Sorry if that's a confusing question.
I have a Leaf and I can tell you how mine reacts. It helps a lot to have it warm in the garage to start. The car does not warm up like an ICE vehicle. Once you are in the cold the cars HVAC has to start working. It also starts to run the thermal management for the battery. Over time think of the car as cooling down.

Use the heated seats and steering wheel in the cold. Keep the heater down. I've taken the leaf out at -15F a few times. I keep the heat down at like 60 and the heated seat on high.
 

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0.3 is the rolling resistance of loose sand. The traction coefficient μt is 0.3 - 0.4. this is essentially a sand trap. A vehicle would need enormous tires at low pressure to navigate sand like that. If you see a car on the beach it is on hard pack sand with a c~ 0.04 - 0.08. Much closer to concrete.
Apparently the beaches you drive on are different from the ones I have driven on where loose sand is indeed plentiful and it is also clear that you have missed the point. When you gain some experience with BEV you will quickly learn that the condition of the substrate has profound effect on the rolling resistance which, as it is an appreciable part of the total load, in turn effects consumption. Even wet pavement as opposed to dry would take my X's consumption from about 300 Wh/mi to 380 or so.

The thing you need to understand is that you will onlu get EPA-like consumption on dry level concrete (or bitumen). Any deviation from that and it will go up. What this means to you practially is that you should always have your eye on the Wh/mi meter. If you leave the road to drive on a beach it is going to go up and how much it goes up determines how much range you will lose. In loose sand it can get to kwh/mi. In more tightly packed sand it won't be that dramatic but even a doubling will cut your range in half. I suppose a simple indication would be whether the vehicle leaves any kind of track or rut (as it does in looses sand). Such a mark indicates that material has been moved and it is the work required to do that which results in the augmeted rolling resistance.
 

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Apparently the beaches you drive on are different from the ones I have driven on...
Completely agree with this. I won't take the R1S onto the beaches in NC because it's too heavy and will get stuck. I don't think a 12k-lb winch will be enough to get out of that mess...

Now, if we're talking by the water's edge, I'm not concerned, but you've got to go through the soft stuff to get there. Range is 0 miles when stuck, haha.
 

ajdelange

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Completely agree with this. I won't take the R1S onto the beaches in NC because it's too heavy and will get stuck. I don't think a 12k-lb winch will be enough to get out of that mess...

Now, if we're talking by the water's edge, I'm not concerned, but you've got to go through the soft stuff to get there. Range is 0 miles when stuck, haha.
The beaches I used to drive on with 4-Runner and Landcruiser were in North Carolina mostly near Oregon inlet and the conditions are exactly as you describe. Very soft sand with deep ruts between the highway and and the good fishing spots. All manner of 4WD vehicles traversed that chunk of beach. I don't recall anyone getting stuck.
 

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The beaches I used to drive on with 4-Runner and Landcruiser were in North Carolina mostly near Oregon inlet and the conditions are exactly as you describe. Very soft sand with deep ruts between the highway and and the good fishing spots. All manner of 4WD vehicles traversed that chunk of beach. I don't recall anyone getting stuck.
Might've been the conditions. We had a good group of FJ's together on Hatteras Island right after they repaired and reopened highway 12 after some hurricanes. A lot of guys got stuck, in our group and other Jeep/4wd groups. Single winching couldn't get most vehicles out, so it was usually 2-3 trucks daisy-chained to pull out a single truck. Deepest sand I've encountered and closest I've come to getting stuck myself. Anything stock height just dropped straight onto the frame. Normally Hatteras is decent, but that trip has me a little more paranoid about sand in heavier vehicles.
 

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Apparently the beaches you drive on are different from the ones I have driven on where loose sand is indeed plentiful and it is also clear that you have missed the point. When you gain some experience with BEV you will quickly learn that the condition of the substrate has profound effect on the rolling resistance which, as it is an appreciable part of the total load, in turn effects consumption. Even wet pavement as opposed to dry would take my X's consumption from about 300 Wh/mi to 380 or so.

The thing you need to understand is that you will onlu get EPA-like consumption on dry level concrete (or bitumen). Any deviation from that and it will go up. What this means to you practially is that you should always have your eye on the Wh/mi meter. If you leave the road to drive on a beach it is going to go up and how much it goes up determines how much range you will lose. In loose sand it can get to kwh/mi. In more tightly packed sand it won't be that dramatic but even a doubling will cut your range in half. I suppose a simple indication would be whether the vehicle leaves any kind of track or rut (as it does in looses sand). Such a mark indicates that material has been moved and it is the work required to do that which results in the augmeted rolling resistance.
They must be. The sand around the great lakes specifically Buffalo is very hard packed where vehicles drive on it. It doesn't leave much of a mark after passing. In thinking about it I'm pretty sure they used heavy machinery to pack the sand down.

In my Leaf I haven't had much of a hard time driving on dirt roads in the mountains of Colorado. The elevation gain is likely masking most of the effects of a dirt road. It is like 3,000 ft of gain in 15 miles from my house to the place I drive to hike.

I will beware on sand if I am ever driving on it.
 

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In my Leaf I haven't had much of a hard time driving on dirt roads in the mountains of Colorado.
I drive a lot on dirt roads in the summer when they are packed so hard that it is sometimes difficult to tell that they aren't paved. Definitely no track is left. Under these conditions I do not notice increased consumption RE concrete/bitumen.
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