Ok, who will be the first Model S to beat this record?

[Todd Burch]

You would wreck a Model S battery within one day just for bragging rights? I think that Zoe/Leaf/Volt have a battery chemistry suitable for repeated high charge/discharge rates. Tesla chose to go another way (or why did they exclude the 40kWh pack from supercharging?).

For the record, this 24 hour record would require about 6 supercharge cycles. Far from wrecking a battery, I hope!

[VolkerP]

It's not only the supercharger cycles but the high discharge rate that worry me. 24h at high temperatures and charge/discharge rates are just far more detrimental than everyday use with the occasional highway run. Probably the A/C would run full blast to remove the heat from the battery pack (so you better pick a cold day) and still the cell core might experience high temperatures. You need a high temperature gradient to remove large quantities of heat.

I am quite sure Tesla will not run a "farthest distance in 24h" publicity stunt. Instead, they will demo their supercharger network when it's up and running. Like they did with the Roadster roadtrip crossing the continent from California to the NAIAS @Detroit back in 2010.

Perhaps they can cut that 18 days trip into 8? That would raise some attention.

[Norbert]

I calculated the above numbers using the actual Model S graph Tesla posted, and including charging time.

Extrapolating Tesla's chart, 108 mph gives a range of about 100 miles or so. At that speed, you deplete a full battery in ~56 minutes, then need to wait for it to fill up again (which is the same amount of time regardless of the speed you travel). If you assume 1 hour to charge, a full cycle from topped off battery-->depleted-->topped off again takes 1 hr, 56 minutes, in which you travel 100 miles. So average speed is ~51mph. I fail to see how this is better than an average speed of 57mph traveling at 80 mph.

In reality, the less number of times you have to stop to charge (get out, plug in, slow down, speed up, etc.), the faster your time will be, so the ideal speed is probably even slower than the peak that these calculations would indicate.

When I posted, I was about to leave and hadn't noticed your post yet. My point was more to say that the speed one would use (on a race track) would be > 50 mph.

Mainly I see that the anticipated range curve, a few months ago, was different than the real Model S range curve, which Tesla posted.

However, about the assumptions:

1 hour for charging would be 85 kW, however we heard the SuperCharger would be 90 kW in so far as I recall. It is not necessary to charge full to reach the optimal times/distances. You can also charge only 50%, to be able to use the full charging speed (instead of slowing down at the end).

At 90 kW the optimal speed will be higher.

The curve becomes flatter and flatter at the end, linear extrapolation will give a different result.

[Norbert]

Linear range behavior across pack sizes / chemistries: The 60 kWh S gets (60/85) times the range of the 85 kWh S, and (40/85) times the range for the 40 kWh S.

With linear range behavior across pack sizes, the distance achieved should be the same for all sizes. I'm not sure (yet) why your calculation finds these large differences, but one reason is perhaps that you always use full charge cycles. However at the end, the battery needs to be charged only as much as it will be used at the end, saving time and allowing a larger distance.

[brianman]

Assumptions:

• Linear range behavior across pack sizes / chemistries: The 60 kWh S gets (60/85) times the range of the 85 kWh S, and (40/85) times the range for the 40 kWh S.
• SWAG: Hours per full charge [HPC] is 1 for all 4 configurations (R, S85, S60, S40).

(1) With linear range behavior across pack sizes, the distance achieved should be the same for all sizes. (2) I'm not sure (yet) why your calculation finds these large differences, but one reason is perhaps that you always use full charge cycles.

(1) If the range for a full charged battery pack was the same across battery packs, then we should just all save money and buy the cheaper one.
(2) Re-read the bullet you didn't quote (but I did)...

[Norbert]

(1) If the range for a full charged battery pack was the same across battery packs, then we should just all save money and buy the cheaper one..

Not the same, but linear (proportional) to the capacity (that is, ignoring the weight influence).

(2) Re-read the bullet you didn't quote (but I did)...

OK, appears you mean different charging speeds, then certainly. That was also my point. Didn't get that on first reading since the 40 kWh pack and Roadster don't actually have supercharging. (So they can't actually charge in 1 hour.)

[Norbert]

I fail to see how this is better than an average speed of 57mph traveling at 80 mph.

While I'm trying to get a good curve fit, so I can use the spreadsheet formula (seems difficult, unfortunately Tesla didn't supply a spreadsheet this time), let's start with the 90 mph time:

Edit:
@90 mph, range is 150 miles. Assuming 1 hr of charging, that's 150 miles/90mph = 1.7 hrs + 1 hr for charging = ~55.55 mph average.
@80 mph, range is 200 miles. Assuming 1 hr of charging, that's 200 miles/80mph = 2.5 hrs + 1 hr for charging = ~57 mph average. <---There's approximately the sweet spot.
@70 mph, range is 240 miles. Assuming 1 hr of charging, that's 240 miles/70mph = 3.4 hrs + 1 hr for charging = ~54.5 mph average.

The range at 90 mph should actually be better than 160 miles, since the curve is getting flatter at higher speeds, by about, or more than, 5 miles (yet even with 160 miles you get a better speed at 90 mph). From 70 mph to 80 mph, range goes down by 40 miles, so from 80 mph to 90 mph, the difference is maybe 35 or even less. So 165+ miles range at 90 mph.

For easy comparison, I'll just use 85 kW charging speed + 1 hour as well:

@90 mph, range is 165 miles. 165 miles/90mph = 1.83 hrs + 1 hr for charging = ~58.2 mph average.

At that point, average speed will still slightly increase with faster driving speed, and with 90 kW charging it will go even further up, until faster driving speed will slowly start to decrease average speed. I'm guessing the optimal speed with 90 kW charging is above 95 mph, perhaps even around 100 mph.

[Norbert]

And with 90 kW charging, average speed (on a race track) should then be around 61 mph, with a driving speed of maybe 98 mph.

If you start with a full battery, the distance covered in 24h should be about 1,500 miles.

The driving speed of the Zoe, with 43 kW charging, was probably somewhere around 70-75 mph (average speed around 42 mph).

[Todd Burch]

And with 90 kW charging, average speed (on a race track) should then be around 61 mph, with a driving speed of maybe 98 mph.

If you start with a full battery, the distance covered in 24h should be about 1,500 miles.

The driving speed of the Zoe, with 43 kW charging, was probably somewhere around 70-75 mph (average speed around 42 mph).

Sounds like we mostly agree, with the primary difference being our extrapolation of Tesla's range curve. Looking at it closer I agree that range @90mph does look to be closer to 165 miles and maybe 150 miles at 100mph...in which case closer to 100 mph is the peak.

[Todd Burch]

It's not only the supercharger cycles but the high discharge rate that worry me. 24h at high temperatures and charge/discharge rates are just far more detrimental than everyday use with the occasional highway run.

With a liquid cooled battery pack and a constant 100 mph drive, would the battery get that hot? I was under impression that the true thermal stresses on the battery come from hard acceleration and regen. Holding a steady 100mph--especially with liquid coolant running around the battery--probably won't make the battery too hot...although this is just a guess. Battery cooling should be quite a bit more effective than on the Roadster.