Cybertruck Range Prediction + Cell Calculation + More [Sources]

[Jhodgesatmb]

And it goes without saying that Model X has to be more aero than CT, based on cross sectional area alone. Not to mention total drag coefficient.

Does it really 'go without saying'? I seem to recall Elon Musk saying he thought that the CT drag coefficient could be as low as 0.30. I saw a page on Google that claims the drag coefficient of the Model X is 0.25. I do not know how much of an impact 0.05 would make in terms of range. I am sure it is significant but not how much.

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[Jhodgesatmb]

Unless you are leaving your dog in your truck at the beach for days at a time, it’s not needed.

I leave my dog in the Model Y on Dog Mode while I kiteboard here in the San Francisco bay area (generally around 15 degrees cooler than Hawaii) and it works fine. Dog Mode will turn off if the battery SOC goes below 20%. I suspect that the CT will rarely have that kind of problem in daily use.

 

[Ogre]

The CT 'can' have a ground clearance of 8", which is less than my old Lexus RX. It would then be more like a wedge pushing through the air than a block like the F150 Lightning. I recently drove a rental Model X and played a bit with the suspension. Tesla had it set to 'low' but it also had a 'very low' setting. The difference was less than an inch, but the total range was only a couple of inches. Taking the CT through its entire suspension range could be quite the ride

The Rivian can adjust it’s suspension which should also give it an efficiency edge to the F150. (Related Rivian just did an OTA update to add 8 miles to their range).

The air suspension and I believe smaller frontal area should give the Cybertruck a huge range advantage. Cybertruck is a bit shorter than the F150 and the body is all around narrower and tapers to the top which makes it even thinner near the top of the truck. I think there will be a significant difference in surface area (and thus total drag).

 

[samroy92]

We know that it has an efficiency of ~1.7 KwH/mile and weighed 81,000 lbs. We know that the Model X has an efficiency of .32 KwH/mile. If the CT has a tow rating of 14,000 lbs and weighs around 6,000 ls then it will be 1/4 (i.e., ~20,000 lbs) the tow weight of the Semi. A quarter of the efficiency of the Semi would be about .425 KwH/mile. The Semi has about an 850 KwH battery pack. If the CT has an efficiency between .32 and .425, and 1/4 of the Semi battery size (i.e., ~212 KwH), would it be reasonable to then expect a similar range of 500 miles?

I have no idea how to perform these kinds of calculations. Can someone that knows how to do this please correct me? I am assuming that there is a linear relationship and that they can actually be scaled across vehicles. If in fact the CT efficiency is closer to the Model X, then the size of the battery pack could be reduced to 160 KwH and achieve the same range. But the big thing here is that these calculations, if at all valid, are based on a 20,000 lb total weight.

I can help.

1. If the Cybertruck has an efficiency between 0.32 and 0.425 kWh per mile - lets call it smack dab in the middle: 0.373 kWh per mile.
2. If we take 212 kWh battery pack given above with 0.373 kWh/mile we get 212/0.373 = 568 miles of range.
3. Battery pack being reduced to 160 kWh with the same assumptions above yields 160/0.373 = 428 miles of range.

I think 428 miles of range is pretty realistic - No doubt the efficiency may be a little worse and the pack size may be a little bigger. Either way this is why in the beginning of this thread I have long predicted around this 400 mile mark for the longest range first production Cybertrucks

One final note: If you want we can go into the hardcore calculations on cD coefficient of drag and how it combines with weight to produce efficiency. Its more complex but happy to try.

 

[Jhodgesatmb]

I can help.

1. If the Cybertruck has an efficiency between 0.32 and 0.425 kWh per mile - lets call it smack dab in the middle: 0.373 kWh per mile.
2. If we take 212 kWh battery pack given above with 0.373 kWh/mile we get 212/0.373 = 568 miles of range.
3. Battery pack being reduced to 160 kWh with the same assumptions above yields 160/0.373 = 428 miles of range.

I think 428 miles of range is pretty realistic - No doubt the efficiency may be a little worse and the pack size may be a little bigger. Either way this is why in the beginning of this thread I have long predicted around this 400 mile mark for the longest range first production Cybertrucks

One final note: If you want we can go into the hardcore calculations on cD coefficient of drag and how it combines with weight to produce efficiency. Its more complex but happy to try.

My calculation (if you want to call it that, actually more of a comparison with the Semi) was focusing on payload and towing of the Semi. My range number was supposedly/hopefully for a full towing capacity on a similar route (Fremont to San Diego). Is it possible that that aspect of what I was guessing at is viable? 428 miles fully loaded would be more than acceptable to everyone here.

 

[samroy92]

Edit: I am revising my range estimates down due to empirical evidence of UCSD teardown of 4680 cell. I think it is likely that yields on Cybertruck 4680 will be in the 90-100Wh per cell range. This puts pack capacity at 130.5kWh - 152kWh or 326mi-380mi

This seems increasingly likely now with the 350mi range rumors. I hope they aren't true!

 

[Jhodgesatmb]

This seems increasingly likely now with the 350mi range rumors. I hope they aren't true!

Why don’t yous-all keep your ‘rumours’ to yourselves. If you have a statement from Elon or Drew then by all means share it. Otherwise let’s stick with what Tesla announced at the unveiling and is still publishing (it still says up to 500 miles on the Tesla site). So a 350 mile CT will be the dual motor trim. Is that what you are going for?

 

[samroy92]

So a 350 mile CT will be the dual motor trim. Is that what you are going for?

Trust me man, I truly hope it is 400-500mi of range. But no not just dual motor, I think this is the limit of the batteries + efficiency they can achieve with current 4680 capacity, but I am hopeful that they will have a 500mi range Cybertruck eventually. Maybe a few years from now.

 

[ninja6r]

Trust me man, I truly hope it is 400-500mi of range. But no not just dual motor, I think this is the limit of the batteries + efficiency they can achieve with current 4680 capacity, but I am hopeful that they will have a 500mi range Cybertruck eventually. Maybe a few years from now.

Aren't they double stacking the pack though? I swear they told motortrend the long range would have that.

 

[samroy92]

Aren't they double stacking the pack though? I swear they told motortrend the long range would have that.

Not confirmed - people speculate both ways

 

[JBee]

I don't think a double stacked 4680 works well as a structural pack, so they will stick to a single stack. It would be very difficult to make a two layer pack but with different cell numbers for example, because to be structural they would have to exactly overlap one layer of cells over another. It would also mean they would have to do two interior layouts or have a false floor on top of the single stack. Both unlikely.

But according to my rough calculations I think we'll get a 420mile range version on a single stack with a 10% buffer, if you use the same setbacks used in a MY 4680 structural pack on the CT floor pan.

This is all very approximate though, given that we really lack any real figures on actual CT consumption. Without that calculating range is like asking how long is a peice of string...

 

[KScheidt]

MotorTrend was definitely invited behind the scenes leading up to the initial unveil and were advised that the "500 Mile Range" version would have a double stacked battery . . .

"Feeding the motors is Tesla's "latest" battery technology, of which the company has shared little. The standard battery pack is mounted underneath the cab, just forward of the roll-up tonneau cover's storage compartment (beneath the pickup bed floor), and offers about 300 miles of claimed range. A new, double-stacked battery will give a tri-motor Cybertruck up to 500 miles of range. A base single-rear motor Cybertruck will have up to 250 miles of range. Construction of the prototype is "unibody-on-frame" in the same vein as the new Land Rover Defender, but the production Cybertruck will be pure unibody."

https://www.motortrend.com/reviews/tesla-cybertruck-electric-pickup-photos-info/

Whether this is still true or makes it into production four years later remains to be seen but it was certainly the intent at the outset.

 

[anionic1]

Interesting, if they only use space in the passenger floor they would probably have to double stack. Given that in all other Tesla models the battery pack is between the front and rear casting I assumed using wheelbase was a decent barometer. Glad the post sparked some conversation.

They will certainly double stack and not pass the midgate with the batteries. Previous post on the recent BIW images clearly show a deep recess for where the tonneau cover will coil up and prevent the continuation of the battery pack. Also, watching the video of Franz's kids getting in the back seat you can clearly see that there is no significant depression in the floor relative to the door threshold. And images below the vehicle seem to show the lower protective plate about flush with the exterior body panels indicating that pack will be about 8" thick, which lines up relatively close to the double stack idea. Also, the CT will experience some of the largest forces of any of their vehicles due to its size and use. Having a thicker structural pack greatly greatly enhances the structural strength of the pack the formula for the moment of inertia of a rectangle, which i assume the structural pack will resemble in section, is

with b being the width of the pack and d being the thickness of the pack. So you can see that the thickness of the pack exponentially increases the strength of the pack. The stress at any point in the pack is inversely proportional to the moment of inertia. I am 95% sure that we will see a double thick pack that only extends from the front fire wall to the mid gate. Any interest in rerunning the calcs on that area with a couble thick pack?

My bet would be for longer range options that they will add an extra hump of batteries under the seats and possibly around the frunk or that vault in the vault where I am showing in red below. It is very clear that the tonneau cover will be in the location i have shown in blue

 

[anionic1]

I don't think a double stacked 4680 works well as a structural pack, so they will stick to a single stack. It would be very difficult to make a two layer pack but with different cell numbers for example, because to be structural they would have to exactly overlap one layer of cells over another. It would also mean they would have to do two interior layouts or have a false floor on top of the single stack. Both unlikely.

But according to my rough calculations I think we'll get a 420mile range version on a single stack with a 10% buffer, if you use the same setbacks used in a MY 4680 structural pack on the CT floor pan.

This is all very approximate though, given that we really lack any real figures on actual CT consumption. Without that calculating range is like asking how long is a peice of string...

You dont need to perfectly stack them although that would not be an issue. And if stacked there is likely going to be a seperator that could transfer unperfectly stacked loads. And generally in a rectangular shape the middle axis is a neutral axis without much force acting on it. The upper and lower diaphragms have the most for acting on them. It is very likely that they will stack the packs.

 

[anionic1]

Thanks for drawing it out, that would definitely require a double stacked pack. In my opinion Tesla will do this:

The structural component of the pack, their big breakthrough, will be casting to casting. (Again in my humble opinion) The rigidity of the Cybertruck will be next level for a truck.

In summary:

you forgot to leave room for the coiled up tonneau cover. the pack will probably start 14"-16" in front of the rear wheel casting. probably in line with the rear door seem.

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