Case for the 800 mile Cybertruck

[Rthardison]

I will go through a few explanations to arrive at assumptions for numbers used in my calculations to arrive at 800 miles of range.

I used to tell friends don’t buy an EV that has less than 200 miles of range. I have since raised my minimum recommendation to 250 miles after taking several long trips in EVs. The logic behind 250 miles of range is we should be able to travel 2 hours on a trip without having to stop for a charge. Anything less is unacceptable compared to driving an ICE. Two hours at 70 mph is 140 miles. Fast chargers aren’t located exactly 140 miles from each other. Add in 25% margin and you get 175 miles minimum range on a trip.
Now, on a road trip, the optimum operating range is between 10% and 80%. Charging above 80% is a waste of time. Of course your first leg can start at 100%, but the rest should start at 80% to avoid excessive charge times. Driving below 10% hoping to make it to the next charger takes years off your expected lifespan. Thus, 10% is an appropriate minimum state of charge to plan on having when arriving at the charge station. Staying between 10-80% of battery capacity uses 70% of rated capacity.
From above, 175 miles minimum trip range is 70% of 250 miles minimum range acceptable for an EV to be usable on a road trip.
We have two real world trucks out now to get efficiency numbers from. The Rivian R1T and Ford F-150 Lightning. I will post video links at the bottom of this post to support the numbers here.
Rivian R1T:
70 mph efficiency: 429 wh/mile
70 mph towing efficiency: 1205 wh/mile
Ford F-150 Lightning:
70 mph efficiency: 500 wh/mile
70 mph towing efficiency: 1430 wh/mile
From these, here are my Cybertruck estimates:
70 mph efficiency: 425 wh/mile
70 mph towing efficiency: 1300 wh/mile
Now for calculations using numbers above:
To use 70% capacity and tow a 7,500 lb travel trailer for a minimum of 175 miles the Cybertruck will need a 325kWh battery. 250 miles x 1300 wh/mile = 325 kWh
Now, without the trailer, this same Cybertruck will get 425 wh/mile x 325 kWh = 765 miles.
The EPA test is different from a 70 mph test. I assume Tesla will achieve 400 wh/mile on the EPA test. Which comes to:
400 wh/mile x 325kWh = 813 miles.
I hope Tesla will build this truck. It will enable us to stop using gas/diesel for long trips pulling a trailer.
References:
F150 range test:
Rivian Range test:
F150 towing range test:
Rivian R1T towing range test:

 

[Crissa]

CATL has announced things ahead of their actual ability to create, though.

Let's see it more than a render and primary test bench, first.

-Crissa

 

[ldjessee]

Why charge more than you need (besides a reasonable buffer) to get to the next charging location?

The reason people fill gas tanks is because the time to fill is trivial. When they choose to not fill up, it is due to cost.

With EVs, it is the opposite, the time to fill is the thing, while the cost is much more reasonable.

So, I would not spend an extra 10 minutes to go from 60% to 80% if the next charging destination is only going to require 52%. Obviously, your charge may vary.

 

[Quicksilver]

Since 90 percent of my driving will be local and I'll charge at home range anxiety will not be a problem for me.
When I do take a long trip I'll plan the route and map out the charging stations I'll need.
What might be a good option/aftermarket idea would be a small battery that could be mounted in the bed of the CT much like diesel trucks carry a spare tank of fuel in their beds either to fuel other vehicles or to fuel the prime mover if you run low. It would have the standard Tesla charger port.
This pack would be good for a hundred miles and not take up too much cargo space. It could also be removable when you are staying local.

 

[Jhodgesatmb]

I will go through a few explanations to arrive at assumptions for numbers used in my calculations to arrive at 800 miles of range.

I used to tell friends don’t buy an EV that has less than 200 miles of range. I have since raised my minimum recommendation to 250 miles after taking several long trips in EVs. The logic behind 250 miles of range is we should be able to travel 2 hours on a trip without having to stop for a charge. Anything less is unacceptable compared to driving an ICE. Two hours at 70 mph is 140 miles. Fast chargers aren’t located exactly 140 miles from each other. Add in 25% margin and you get 175 miles minimum range on a trip.
Now, on a road trip, the optimum operating range is between 10% and 80%. Charging above 80% is a waste of time. Of course your first leg can start at 100%, but the rest should start at 80% to avoid excessive charge times. Driving below 10% hoping to make it to the next charger takes years off your expected lifespan. Thus, 10% is an appropriate minimum state of charge to plan on having when arriving at the charge station. Staying between 10-80% of battery capacity uses 70% of rated capacity.
From above, 175 miles minimum trip range is 70% of 250 miles minimum range acceptable for an EV to be usable on a road trip.
We have two real world trucks out now to get efficiency numbers from. The Rivian R1T and Ford F-150 Lightning. I will post video links at the bottom of this post to support the numbers here.
Rivian R1T:
70 mph efficiency: 429 wh/mile
70 mph towing efficiency: 1205 wh/mile
Ford F-150 Lightning:
70 mph efficiency: 500 wh/mile
70 mph towing efficiency: 1430 wh/mile
From these, here are my Cybertruck estimates:
70 mph efficiency: 425 wh/mile
70 mph towing efficiency: 1300 wh/mile
Now for calculations using numbers above:
To use 70% capacity and tow a 7,500 lb travel trailer for a minimum of 175 miles the Cybertruck will need a 325kWh battery. 250 miles x 1300 wh/mile = 325 kWh
Now, without the trailer, this same Cybertruck will get 425 wh/mile x 325 kWh = 765 miles.
The EPA test is different from a 70 mph test. I assume Tesla will achieve 400 wh/mile on the EPA test. Which comes to:
400 wh/mile x 325kWh = 813 miles.
I hope Tesla will build this truck. It will enable us to stop using gas/diesel for long trips pulling a trailer.
References:
F150 range test:
Rivian Range test:
F150 towing range test:
Rivian R1T towing range test:

Regardless of whether the analysis is valid (and I have no reason to doubt it), it would be wise for Tesla to design the CT range with a non-empty cargo and/or towing load. A 250 mile range with load would certainly be a much higher no-load range. I hope it turns out to be the case as you suggest.

 

[Ogre]

Mentioned this in the other trailer thread, but worth repeating.

Get a more efficient trailer.

https://insideevs.com/news/450670/tesla-model-x-towing-airstream-different-range-results/

Regardless of your truck’s range, you should do this.

Obviously if you are towing cars on a flatbed you don’t have a ton of choice, but if you are towing a camping trailer there are options. Towing an inefficient trailer is just burning money and time.

 

[Rthardison]

Why charge more than you need (besides a reasonable buffer) to get to the next charging location?

The reason people fill gas tanks is because the time to fill is trivial. When they choose to not fill up, it is due to cost.

With EVs, it is the opposite, the time to fill is the thing, while the cost is much more reasonable.

So, I would not spend an extra 10 minutes to go from 60% to 80% if the next charging destination is only going to require 52%. Obviously, your charge may vary.

I agree to only charge to needed charge. I was establishing minimum requirements.

 

[charliemagpie]

Whether we wish to charge to 100% depends on circumstances. &

Whether we wish to drain to 5% depends on circumstances.


If I was driving my CT around for everyday use, for sure, 80% charge is fine, and when it gets down to 20%, charge up again. Either way, I probably wouldn't care.

But

But definitely, If I am towing my RV, I will charge to 100%. I'ts not that I'm towing for weeks on end. 10 to 30 mins extra waiting.. Suits me.

If it gets me to a spot where I will be spending 3 weeks with 8% left... fantastic.
These recommended charging limits are arbitrary. The degradation to battery is pedantic to me.

 

[Rthardison]

Whether we wish to charge to 100% depends on circumstances. &

Whether we wish to drain to 5% depends on circumstances.


If I was driving my CT around for everyday use, for sure, 80% charge is fine, and when it gets down to 20%, charge up again. Either way, I probably wouldn't care.

But

But definitely, If I am towing my RV, I will charge to 100%. I'ts not that I'm towing for weeks on end. 10 to 30 mins extra waiting.. Suits me.

If it gets me to a spot where I will be spending 3 weeks with 8% left... fantastic.
These recommended charging limits are arbitrary. The degradation to battery is pedantic to me.

I like your style. It hurts me to wait an extra 30-45 minutes to get to 100%. Maybe I won’t care so much when I retire someday. Here is a scenario where you charge twice and get six hours of driving in to go approximately 450 miles. Assuming all charges go to 100%.
Drive 150 miles.
Charge 1 hr 10 min
Drive 150 miles
Charge 1 hr 10 min
Drive 150 miles.
Distance covered: 450 miles
Time (assuming 70 mph): 8 hours 45 minutes

I need to start reading to help me slow down and enjoy the journey.

 

[Crissa]

I agree to only charge to needed charge. I was establishing minimum requirements.

175 miles at 80mph is still longer than you should be making stretch and pee breaks.

And if you want to stop less often, drive slower. Air resistance increases exponentially with speed.

-Crissa

 

[Ogre]

Another thought here. Tesla Semi. Goes 300 miles pulling 40 tons. Pricing is in the ballpark of what an 800 mile Cybertruck would look like regardless.

As a bonus, you might even get it sooner.

 

[rr6013]

<quote>Acceleration 0-60 mph with 80k Ib == 20 sec </quote>

Burning through tires there Bubb!

 

[Rutrow]

Driving below 10% hoping to make it to the next charger takes years off your expected lifespan.

Uh... you'll have to show me some citation for that assertion. I'm an avid EV aficionado and have NEVER heard anyone knowledgeable in Li ion batteries say discharging below 10% hurts the lifespan of your battery. What IS true, it that you shouldn't STORE a Li ion battery at a low state of charge (and by STORE we mean for periods of months or more) but on a road trip you'll only be at a low state for minutes/hours before charging back to a healthy state of charge. Similar goes for charging to 100%. The best practices strategy is to hit your 100% SOC as close to departure time as possible. Either schedule your charge the night before departure to start charging in the wee hours, or better! ramp down your charging amps so that a slow charge all night gets you to full at departure time.

The primo strategy for road trip charging is to leave with 100% and go to the farthest charger you can get to. Charge just enough to arrive at your second charging stop at as low a state of charge as you, and your travelling partner, are comfortable with (my S/O demands a >12% buffer, I aim for <2%), then do the same until your final DC fast charging stop for the day. This last DC stop is where you have a decision to make. Will you be staying the night at/near a level 2/destination charger? Or will you need some range at your next stop for local trips or to hit a DC fast charger the next morning? Because THAT will dictate how high to charge then.

Arriving at a DC fast charger at minimal charge allows you to add the most miles in the least time. Charging rates at below 30%-50% (depending on vehicle) will be at the highest kWs, then the taper starts, so unnecessarily charging above those levels along the way is going to slow you down.

So, I would minimize the amount of time your battery is at 100% or 0%, i.e. don't leave it overnight at either extreme, although doing it occasionally won't do much damage to your battery. If you plan to SuperCharge at your intermediate layover, I'd arrive at your hotel at >5% and top up in the morning while you're eating breakfast.

 

[charliemagpie]

I like your style. It hurts me to wait an extra 30-45 minutes to get to 100%. Maybe I won’t care so much when I retire someday. Here is a scenario where you charge twice and get six hours of driving in to go approximately 450 miles. Assuming all charges go to 100%.
Drive 150 miles.
Charge 1 hr 10 min
Drive 150 miles
Charge 1 hr 10 min
Drive 150 miles.
Distance covered: 450 miles
Time (assuming 70 mph): 8 hours 45 minutes

I need to start reading to help me slow down and enjoy the journey.

Lol, exactly

I will be retired. My bravado is from my own perspective.

Yet, having endured more of life's journey and experienced more of its ups and downs, I reassess what is worth bringing onboard and what isn't.

The more the years pass, the more 10-30 minutes waiting become less painful.

 

[Ogre]

<quote>Acceleration 0-60 mph with 80k Ib == 20 sec </quote>

Burning through tires there Bubb!

That’s with 40 tons behind it.

Give that a try that in your truck.

Also... 60 MPH up a 5% grade with the same 40 tons.