Different batteries have different characteristics when it comes to charging; this goes for the various Tesla battery models too. Through the ABRP data collection by generous users, we have quite a lot of real-world data to base our models for use in the route planning, and in this post we give you some insight into the data. The data here is based on 4600 Supercharging sessions from 801 Tesla Vehicles!

First of all, the battery model of a Tesla is not completely clear from the model name. An almost complete list of Tesla batteries includes:

  • BT37: The 75 kWh battery in a Model 3 Long Range
  • BT60: The old S60 60 kWh battery
  • BT70: The old S70 70 kWh battery
  • BT85: The classic “85” kWh battery in a Model S85
  • BTX4: The 90 kWh battery in S90 and X90
  • BTX5: The 75 kWh battery in S75 and X75
  • BTX6: The top-of-the-line battery 100 kWh in S100 and X100
  • BTX7: A rare 85 kWh battery, where we have almost no data
  • BTX8: An 85 kWh battery found in some rare S75 and X75

Model 3 LR – BT37

First out is the Model 3 Long Range battery. There is a limited amount of data in ABRP’s database – only 38 charging sessions from 13 cars – so please contribute! The blue dots are measured data points  and the red dashed line is the present ABRP charging power model.

The estimated battery capacity from the contributing cars is 72.8 kWh.

Model S85 – BT85

Second, the classic S85 battery, which is known for not really being 85 kWh. There is plenty of data here, and as you can see it is charging at very high speed all the way from 0% SoC, but tapers off relatively early.

The estimated battery capacity from the contributing cars is 73.4 kWh. That’s why I wrote “85”. It has basically the same capacity as an S/X75.

Model S70 – BT70

The older S70(d) battery is similar to the BT85, but smaller. From data, the estimated usable capacity is 65.7 kWh.

Model S/X90 – BTX4

The S/X90 battery, is like the “85 kWh” battery also not really living up to its name. The estimated capacity from the data is 79.8 kWh. It differs from the BT85 in that it charges slower at really low SoC (below 10%) but it compensates by charging a lot faster at higher SoC.

Charging at BTX4 battery from 10 kWh to 50 kWh takes 23 minutes. The same charge (in absolute energy, not %) takes 27 minutes in a BT85.

Model S/X75 – BTX5

The “new” 75 kWh battery, sometimes software limited to 60 kWh in a S/X60 has an estimated capacity of 71.6 kWh. The charging curve is similar to the BTX4 and BTX6 batteries, but in absolute power lower due to the smaller capacity.

Charging from 10 kWh to 50 kWh takes 27 minutes.

Model S/X100 – BTX6

The (so far) largest Tesla battery is a real beast. The charging is, in a large SoC region, limited by the 120 kW power output of most superchargers. 20 minutes to charge from 10 kWh to 50 kWh. As you can see from the data points below, owners tend not to ever go much below 10% SoC, and there is a reason – they have so much capacity. 95.7 kWh according to the ABRP data.

Model S/X75 Unicorn – BTX8

There are a couple of odd Model S and X 75 with an 85 kWh battery, software limited. It is rumored that they have been fitted with left over BT85 batteries, but the charging curves do not look exactly the same. Anyhow, the result is a battery pack with a lot of extra margin and really fast charging. Lucky owners – 14 of them contribute data to ABRP!


Battery CodeTesla ModelEstimated Usable Capacity10 kWh -> 50 kWh charge time
BT373 Long Range72.8 kWh23 min
BT60S6056.3 kWh42 min
BT70S7065.7 kWh33 min
BT85S8573.4 kWh27 min
BTX4S/X9079.8 kWh23 min
BTX5S/X7571.6 kWh27 min
BTX6S/X10095.7 kWh20 min
BTX8Rare S/X7525 min

Battery size matters. Not only does a bigger battery take you further between charges, it also charges faster. This will make a trip in a Tesla Model S100d faster than in an S75d.

Want to contribute your vehicle’s data? Log in to MyTesla in ABRP and leave the “Share data” checkbox checked. 


JP · 2018-06-10 at 20:31

How do you calculate the estimated kWh? I ask because I have info on the number of cells in each of the BTX4,5,6,7,8. Assuming available capacity is directly related to the number of cells, your estimated capacity is not consistent.

    Bo · 2018-06-11 at 07:32

    The estimated kWh is calculated from the Tesla reported “number of charged kWh” for each session and the corresponding increase in SoC%.
    I assume that the battery module construction and battery cell chemistry has changed over the models so we cannot expect the same performance from the same number of cells.

      JP · 2018-06-11 at 17:01

      Ok. Focusing on the BTX5 through BTX8 batteries, I am pretty sure the chemistry has remained constant. These packs vary in the number of cells per module and the number of modules, which has implications too for the number of cells in parallel and in series. More cells in parallel can increase charge and discharge rates, but fewer cells in series implies lower voltage.

      If the BTX6 pack is nominally 100 kWh, the implied kWh capacity for the other packs are:
      BTX4: 86.0
      BTX5: 75.3
      BTX7: 81.4
      BTX8: 86

      I own one of the BTX7 in a S 75D..

        Bo · 2018-06-11 at 17:23

        I think the BTX6 pack is nominally 102 kWh, and then we have to subtract the 4 kWh bricking buffer. However, what is estimated from the data is the actual remaining capacity, so 95.6 kWh does not sound too off. Neither do the other battery models, I think.
        Congrats on the bonus battery in your car!

Joseph · 2018-06-10 at 22:44

“Battery size matters. Not only does a bigger battery take you further between charges, it also charges faster. This will make a trip in a Tesla Model S100d faster than in an S75d.”

Not so fast

The 10 to 50 kWh charge time for the S/X 100kWh and the 3LR differ by only three minutes in favor of the 100kWh.

However the 3 LR is known to have much greater efficiency, it’s around 4 miles/kWh versus the S100D at 3 ish. Clearly that car has the larger range for that time.

    Bo · 2018-06-11 at 12:06

    You’re right, I did not include the Model 3 in the comparison. I will cover that in another post 🙂

Zoomit · 2018-06-14 at 04:24

Can you clarify that the displayed SoC [%] on the graphs are a percentage of the usable battery capacity and not the total battery capacity? Technically, State of Charge would reference the total battery capacity.

Maximilian Holland · 2018-06-14 at 08:21

Just wanted to say thank you for sharing this really great data Bo. It’s hard to be able to get beyond anecdotes when looking at charging speeds and consumption vs. speed etc. Fantastic to have independent data points. Keep up the amazing work!

Mark Neal · 2018-06-30 at 14:56

Excellent article! I am very confused when it comes to Tesla car batteries but I am very interested into learning about the entire vehicle structure. This article gave me a little idea about the batteries. Any helpful links where I can understand how the vehicle works and its components?

Tesla Battery Charging Analysis Reveals Different Charging Rates For Each Battery Size | CleanTechnica · 2018-06-13 at 03:10

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