New 120Kw Model S

New 120Kw Model S

With the recent huge reductions in the cost of the Models S and X, I was just thinking about what could be the next battery size for a new Model X and Model S by working from the old 18650 battery cells specification compared to the new 2170 battery cells specification that power the Model 3.

Please feel free to correct my maths, but as I understand it assuming a current P100DL has 8,256 cells of the 18650 batteries each weighing 44grams and generating 3.7v at 3400mA. Equals 363.264 kilos in weight and an actual power storage of some 103.860Kwh. Tesla holds about 3-4% of a battery pack in reserve to prevent it from becoming fully discharged, hence the 103kw calculation seems correct for a P100DL.

The volume of 2170 battery is 24.250 mm3 the volume of a 18650 battery is 16.540 mm3 so the number of 2170 batteries that would take up the same volume as 8,256 18650 batteries would be 5,631 giving a total power storage assuming 6,000mA per cell of 125kw which when allowing for a 4% reserve would mean a usable 120kw battery with a range of approx. 402 miles.

This 120kw battery pack would weigh a hefty 371 kilos but only 8 kilos more than the 100kw 18650 battery pack of the same volume. Due to the 5mm increase in the height of the 2170 the battery pack floor pan would have to be modified to allow for this in the Models SX which may or may not be a major issue.

Faster charging of the 2170 battery in a Model SX would also be an added benefit if they also use the M3 type of cooling system.
What do you think the next Model S and X Battery pack sizes or ranges will be as Tesla are now moving away from declaring battery pack values in KW.

NKYTA | 02. November 2019

RLR? Really long range.

It’s hard to know exactly where the Panasonic contract is for the 18650 batts.
And, without direct evidence, whether there is any overhead for S/X from the GF for the 2170‘s...


packpike | 02. November 2019

I've been assuming that the next iteration would be 110kW, but 125kW would be awesome! I’m holding off trading in my 2018 75D for the bigger battery, whatever it may be. | 02. November 2019

@Technistore - The numbers seem good, but in calculating volume, there are cooling pipes. I have no idea if this would consume more volume or less with different cell sizes. Then there are the efforts of cooling and heating the battery. Both these systems may need to be re-engineered to deal with the larger capacity. Same for the inverter and contactors.

A new battery does appear to be in the works in the Plaid version, but so much has to be designed to deal with a larger pack and capacity. I wonder if they will jump to the 200 kW pack, the unconfirmed battery size in the Roadster 2020. Likely has a new battery formulation, and perhaps even a new cell size.

RedShift | 02. November 2019

I.e, just 30 miles gained for an increase of 25 kWh. (Current range being 373 miles for the 100 kWh battery)

An 8% gain for a 25% increase in battery capacity.

I don’t think that right, even while knowing that it’s not a linear relationship as weight increases.

Bighorn | 02. November 2019

I didn’t walk the numbers but 400 miles seems way low for 120 kWh. Two minor points. The numbering system hasn’t always matched available kWh i.e. the 85s provided 74 kWh, and they’re not divulging pack size anymore in marketing. | 02. November 2019

Also, Tesla keeps improving efficiency. Plaid with 3 motors could be more efficient than the current design. If the W/m improves by 20%, the same existing battery provide 20% more range (i.e. 373 * 1.2 = 448 miles).

In hindsight, I doubt Tesla will need or offer a 200 kW battery.

Bighorn | 02. November 2019

You should correct your usage of kW vs kWh since you seem to know the difference. A lot of people are unaware and this won’t help get them on track. | 02. November 2019

@BH - Thanks. Yep, should have been 200 kWh battery.

Bighorn | 02. November 2019

It was directed at the OP, but I later saw you slipped one through:)

jordanrichard | 02. November 2019

OP, your title is a bit deceiving because it is as if you are announcing there is a new battery pack.

carlk | 02. November 2019

Yes the title is misleading with wrong unit used. Besides Tesla no longer specifies battery sizes. There will never be a "120 kWh Model S".

inconel | 02. November 2019

if the Roadster gets the 200kWh battery, it would seem wrong to give the S Plaid only 120kWh

Technistore | 03. November 2019

Yes I agree the range of 402 miles for a 120Kwh battery seems low, However I made this rough calculation based on my own P100D model S which when new was rated at 335 miles range so divided by100KWh to arrive at an average of 3.35 miles per Kwh times 120Kwh equaled 402 miles. But you are correct with the latest Model S that should translate to more like 455 miles and for the new Model X more like 377 miles. Sorry to use KWh in this context but although Tesla have stopped referring to their Models Battery sizes in this way it still remains a factor in calculating the maximum range.

Bighorn | 03. November 2019

KWH is perfectly appropriate whether Tesla markets by battery capacity or not.

jordanrichard | 03. November 2019

Not to be a wet blanket here, but we really shouldn’t be talking or rather phrasing this as if this battery exists or that there is even one in development because it could create a freezing frenzy of hope and when it never come to fruition, people will get pissed.

There is a long standing history of people getting all worked up about what will be in the next update and then when it didn’t happen, they got pissed even though Tesla never said “x, y, z” was going to be in the update. | 03. November 2019

I'm not sure why the battery kW has much meaning anymore and is likely the reason Tesla has dropped it from the model names.

Would you want a car that has 204 miles of range with a 90 kW battery (eTron) or one with 373 miles of range with a 100 kW battery if the range is the sole consideration? If you want range then you need to state the range you want. The battery size is a factor, but one of many. Weight and size are major contributors (or detractors) for range. Motor efficiency is also a huge factor. Making larger and larger battery packs cause other problems, such as major added costs, reduced cargo/cabin space and weight that reduces handling. So many tradeoffs.

Technistore | 03. November 2019

My apologies for the main heading I should have put a ? mark at the end of it, but I did state at the beginning I was just thinking about what the next battery pack size might or could be using the current battery technology available.

Bighorn | 03. November 2019

You can edit the very first post including the title—that’s what I was suggesting earlier wrt the kWh error. | 03. November 2019

And I completely screwed up my last post. Should be kWh everywhere. I know better!

Bighorn | 03. November 2019

No, I try not to be the BrianH of misspellings, though occasionally it is worth pointing out.

bp | 04. November 2019

Musk has previously commented that Tesla could be at or near the limit of how far they'll take the Model S range - when Tesla makes changes to the battery packs, it's more likely they'll look for cost/weight reductions and charging improvements than continuing to increase range.

When Model X is used for towing, it could use a larger battery pack - and if Tesla is able to merge S/X production onto the same line, that would provide more justification to provide more range for S.

For non-towing, the current S/X battery packs likely meet needs for the vast majority of S/X owners, and with the competitors unable to get anywhere close to matching Tesla's current range (they still haven't matched the range of the 2012 Model S), Tesla isn't under much competitive pressure to provide more range - at least not for now.

jordanrichard | 04. November 2019

More physical batteries to increase the total Kwh becomes counter intuitive because you are also now carrying more weight. So the increase is power would have to be proportionally more than what it takes to carry the added weight.