Here is a screenshot from the EPA spreadsheet that has the new data. The numbers on the right side show 270.1 miles for city range and 247.6 miles for highway range. Combined range is 55% of city + 45% of highway range. In this instance, the combined range is exactly 260.0 miles because of 270.1*0.55 + 247.6*0.45= 260.0.
However, these are not the actual scores. The actual numbers are 274.1*0.55 + 251.2*0.45= 263.8. You can see these numbers when you select the cells and look at the formula bar. City range is 274.1 miles and highway range is 251.2 miles.
Here is a table that summarizes the current situation. Advertised range, EPA rated range and EPA combined range, are different names for the same thing. In an ideal world, the advertised range of the LR should be 318 miles, LRD and P should be 296 miles and MR should be 251 miles.
A detailed version of this table that shows the range numbers at different speeds can be found here: Tesla Range Table. I updated this table based on the latest data in this EPA document.
Other new data points in this document are the MPGe (miles per gallon equivalent) numbers. For Model 3 Mid Range, highway MPGe is 116.97. EPA defines MPGe as range per 33.7 kWh electric meter consumption. 1 gallon of gasoline is equal to 33.7 kWh energy according to EPA. That’s the conversion factor they use for all EVs. You can compare the MPGe numbers of different Teslas here on the EPA website.
Looking at the MPGe numbers, we can do some calculations. If highway range is 116.97 miles per 33.7 kWh electric meter consumption and total highway range is 251.2 miles, then we can calculate the total electric meter consumption for a full charge. It would be 33.7*251.2/116.97= 72.37 kWh for the Mid Range. This data alone wouldn’t mean anything but luckily we also know the following about the Long Range Model 3 battery:
- 89.41 kWh electric meter consumption
- 80.5 kWh total capacity
- 78.27 kWh usable capacity
- 4416 cells
If 89.41 kWh wall consumption corresponds to 78.27 kWh usable capacity, then 72.37 kWh wall consumption would mean 72.37*78.27/89.41= 63.35 kWh usable capacity for Mid Range.
The LR pack has 80.5-78.27= 2.23 kWh buffer (brick protection). Model S data shows that the buffer remains the same for 75, 70, and 60 kWh versions. Therefore it should be the same for LR and MR (2.23 kWh). That means the total capacity of the MR pack should be 63.35 kWh usable capacity + 2.23 kWh buffer= 65.58 kWh.
If 80.50 kWh corresponds to 4416 cells, then 65.58 kWh would be 65.58*4416/80.50= 3598 cells. This looks like a rounding error. I will assume 3,600 cells. Here is a summary:
I want to be clear that 3,600 cells for the Mid-Range battery is an estimate I’m calculating based on electric meter consumption numbers. 3,600 cells is kind of an odd number because all Model 3 packs have 96 bricks and if each brick had 37 cells, the cell count would be 3,552 cells. If it were 38 cells per brick, cell count would be 3,648. For 3,600 cells to be true, the pack needs to have 48 bricks with 37 cells and 48 bricks with 38 cells. That’s what the theory shows. I’m sure we will eventually find out whether 3,600 cell is the actual number. My previous estimate based on vehicle weight was 3,648 cells but based on this latest data, I have to go with 3,600.
I wish EPA would stop using the 55% city plus 45% highway method to calculate EPA rated range. They could continue using the combined range for MPGe and switch EPA rated range from combined to just highway range. Expecting Tesla to advertise realistic numbers while all other EV manufacturers continue to advertise whatever the EPA score shows would put Tesla at a disadvantage. Therefore the solution should be to making the range numbers more realistic for all EVs.
Even though EPA rated range is somewhat optimistic, it doesn’t look half as bad if we look at the messy situation in Europe. They used to have a range test called NEDC which was too unrealistic. They came up with a new range test called WLTP which was supposed to be better but it’s still too optimistic.
For example, the numbers are as follows for Model 3 LRD:
- 296 mi (476 km) EPA highway range
- 310 mi (499 km) EPA rated range in North America (5% over EPA highway range)
- 338 mi (544 km) WLTP rated range in Europe (14% over EPA highway range)
Even the 296 mi EPA highway score is not exactly a good measure because it corresponds to the range at 68 mph. The range drops to 287 mi at 70 mph and 264 mi at 75 mph. For more details, see the Tesla Range Table.
Update (9 Dec 2018): It looks like all 96 bricks need to have the same number of cells for technical reasons because that’s how it works when connecting batteries in series. Therefore the actual cell count should be either 96*37= 3,552 or 96*38= 3,648 cells.