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Now taking bets on Model 3 battery size

We are now taking bets on the Model 3 battery size. I'm putting my money on 48kWh.

petochok | January 27, 2015

EmperorTytus | January 27, 2015

2 trims: 50kWh and 70kWh

Grinnin'.VA | January 27, 2015

I think it will be about 60 kWh because that's what I think will be needed to meet the 200-mile range goal. I'd guess that they would have an option for a higher capacity battery to deliver a practical range of about 250 miles.

Red Sage ca us | January 27, 2015

60 kWh minimum.

100 kWh optimum.

Svenssons | January 27, 2015

MS 60 have more than 200 miles today and M3 will be smaller and lighter. 50 and 70 are my bet. 50 kWh will be more than enough for 200 miles. 70 will probably take you about 270 miles. It is smarter to use lighter battery per kWh to decrease weight and cost than increase capacity and cost.

RanjitC | January 27, 2015

I agree with Svenssons and EmperorTytus 50 and 70 sounds right.

Red Sage ca us | January 27, 2015

It depends upon how you calculate it. Starting with the presumption that Tesla Motors wants to achieve an EPA rating of 200 miles or more of range for Model ☰...

You can look at it as Wh per mile expended...
❑ 200 miles at 180 Wh per mile -- 36 kWh
❑ 200 miles at 240 Wh per mile -- 48 kWh
❑ 200 miles at 300 Wh per mile -- 60 kWh
❑ 200 miles at 360 Wh per mile -- 72 kWh
❑ 200 miles at 420 Wh per mile -- 84 kWh

You can also look at what was accomplished with Model S and work backwards, based upon the expected 20% smaller size of Model ☰...
❑ 208 miles EPA rated range -- 60 kWh
...⇒ 208 divided by five, times six, equals ~250 miles range
...⇒⇒ Perhaps an EPA rating of ~225 miles range
❑ 265 miles EPA rated range -- 85 kWh
...⇒ 265 divided by five, times six, equals ~318 miles range
...⇒⇒ Perhaps an EPA rating of ~218 miles range

I believe it is best to make sure that there is more than enough juice on hand to be certain the 200 mile range is achieved during the EPA tests. I don't trust the EPA to not change the testing parameters to something that is unfavorable to Tesla Motors' goals. So yeah, I would go for overkill in this regard.

That means I would want to get a minimum of 225 miles of range using only a 90% charge of the available battery pack capacity, after 'brick' protection. For further insurance that the intended range could be met, I would want it to be possible even if the car were not driven economically. That way you can diminish the complaints of those blessed with thigh high lead boots or who reside inside the arctic circle on Moebius loops that require they always drive uphill in the snow.

225 miles at 360 Wh per mile is 81 kWh. That is 90% of 90 kWh. And allowing for brick protection you get to 100 kWh.

Driven more conservatively, you get 270 miles at 300 Wh per mile... And finally, around ~338 miles at 240 Wh per mile.

Keep in mind that if you apply this formula against smaller battery packs you may not get the hoped for range at all...

❑ 70 kWh battery pack, 63 kWh available for use, ~57 kWh at 90%, yields only 189 miles range at 300 Wh per mile.

❑ 50 kWh battery pack, 45 kWh available for use, ~41 kWh at 90%, gives you only 135 miles range at 300 Wh per mile.

Gen3Joe | January 27, 2015

50kWh and 70kWh is my bet as well

Gen3Joe | January 27, 2015

In terms of Wh per mile the Model 3 should easily be able to match the Nissan Leaf. The Model 3 will have a battery with much better energy density than the Leaf so it will have more energy per pound of car as well as a better drag coefficient.

Over 15,000 miles of driving I've averaged 225 Wh/mi in my Leaf. I expect to average at least this amount in the Model 3. A 45kWh usable would take you exactly 200 miles under this assumption.

Maybe 55 and 75 is more likely to provide some additional buffer.

jonlivesay | January 27, 2015

Three pack options will be available but the most chosen will be the "66" pack.

Grinnin'.VA | January 28, 2015

I agree with the 50 kWh and 70 kWh guesses.

60 kWh.
There will be a total of 500,000 Tesla vehicles produced in 2020 according to the Gigafactory PDF. That same PDF states that the cell output will be 35 gWh/year from the GF with another 15 gWh/year from Panasonic factories over seas. Assuming that 35 gWh/year goes to the 500000 vehicles, that's an average per vehicle of 70kwh. Since that includes 85 kWh Gen II units, the numbers roughly work if all the Gen III vehicles are at 60 kWh.

Assuming that the whole 50000000 gWh/year is used for the 500000 vehicles (not going to happen, the GF will also make stationary packs using the domestic and imported cells) the average Tesla vehicle could have a 100 kWh pack.

If they use more packs than a 35/50 fraction for cars, then we might see 70 kWh average for Gen III.

If every car had an 85 kWh battery pack, it would take 42.5 gWh/year out of a total of 50 gWh/year to keep the cars going. That would leave 7.5 gWh/year for stationary storage.

I'd love to see a 75 kWh Gen III and 100 kWh Gen II, but regardless of what they do, the cars will be fantastic.

Red Sage ca us | January 28, 2015

Oops... I must have been tired before. Noted a typo that should have been:

❑ 265 miles EPA rated range -- 85 kWh
...⇒ 265 divided by five, times six, equals ~318 miles range
...⇒⇒ Perhaps an EPA rating of ~286 miles range

[ ECONOMY | NORMAL | SPORT | INSANE | RIDICULOUS ]

If the Tesla Model ☰ were set up with different, selectable driving modes such as these, I believe they would affect acceleration, top speed, and range in different ways.

❑ ECONOMY -- Perhaps set to a maximum speed of 55-65 MPH, acceleration limited to 7.0 to 9.0 seconds 0-60 MPH, locked at 180 Wh per mile on the drivetrain.

❑ NORMAL -- Maximum speed of 90-100 MPH, acceleration limited to 6.0 seconds 0-60 MPH, locked at 240 Wh per mile.

❑ SPORT -- Maximum speed at 130-140 MPH, acceleration limited to 4.0-5.0 seconds 0-60 MPH, averaging 300 Wh per mile.

❑ INSANE -- Maximum speed at 155 MPH, acceleration limited to 3.0-4.0 seconds 0-60 MPH, allowing 360-450 Wh per mile consumption.

❑ RIDICULOUS -- Maximum speed governed by drivetrain, track conditions, and air resistance only; acceleration without preset limits; and up to 600 Wh per mile consumption. This mode would only be used on a closed race course for the sake of safety, one would hope.
ESTIMATED CAPACITY TO RANGE IN MILES BY EFFICIENCY
kWh ECONOMY NORMAL SPORT INSANE RIDICULOUS
60 270 203 162 108-135 81
85 383 287 230 153-191 115
100 450 338 270 180-225 135
135 608 456 365 243-304 182

holidayday | January 28, 2015

I'll toss my hat into the ring:
50 KWH - for baseline 200 miles at real highway speeds.
75 KWH - for baseline 300 miles at real highway speeds.

About the same time, they'll update the Model S.
60, 85 current designs at reduced prices due to federal incentives sunsetting.
120 kWH for 400 miles at real highway speeds.

Red Sage ca us | January 28, 2015

holidayday: Please define the term 'at real highway speeds'. That seems to vary from region to region, and person to person... Why not give us a number, as you perceive it? Thanks!

AA_4_Tesla | January 28, 2015

Here's my guess:

70 KWH with no extended range upgrade. (for first round of vehicles)

At the same time, the Model S/X gets a bump to 70 KWH and 90 KWH instead of the current 60 and 85.

As production increases or improvements to the batteries start getting rolled out, those numbers would start to rise.

holidayday | January 29, 2015

Red Sage: "real highway speeds"

(disclaimer: I may have exceeded the posted speed limit from time to time)

80 mph when I'm doing road trips.

If I'm going to have a *performance* vehicle, I want it to *perform*.

Red Sage ca us | January 29, 2015

Wow. Where do you drive 80 MPH constantly? I find it interesting that anyone would do so with impunity, and without concern about crossing the path of Officers of the Goshdarned Law.

I'll be honest... In my youth, while protesting what were obviously artificially low speed limits of 55 and 60 MPH on major highways... I set the cruise control to 85 MPH and ROLLED...

But ever since those speed trap highway speeds were eliminated in favor of 70 and 75 MPH zones in many rural areas... With short bursts to 80 and 85 in some areas during daylight... I have actually driven the posted speed limit wherever I go on road trips.

Why is 80 MPH your personal speed limit in a 'performance' car? Why not 120 MPH? I mean, a Honda Civic can do 80 MPH rather easily.

Grinnin'.VA | January 29, 2015

@ Red Sage ca us | January 29, 2015

Why is 80 MPH your personal speed limit in a 'performance' car? Why not 120 MPH? I mean, a Honda Civic can do 80 MPH rather easily.

Hell, even my wife's Prius can easily do 80 mph.
Unless it's going up a hill.

RanjitC | January 29, 2015

He probably lives in Orange county,CA 80 mph is the standard speed outside of rush hour. You generally dont get pulled over for doing that. LA to vegas lots of people do 85.

Red Sage ca us | January 29, 2015

Yeah. The main reason I'm on this is that I doubt there is a way to have a constant 80 MPH, while still getting a very good Wh per mile rating...

holidayday suggested, "50 KWH - for baseline 200 miles at real highway speeds."

But that doesn't seem to work for 80 MPH. I would expect that would be a consumption of at least 360 Wh per mile. Even if there were no brick protection and you used every bit of juice in a 50 kWh battery pack, that only comes to a 139 mile range.

Of course, when you look at the EPA rating for the Tesla Model S 40, you find it was rated at a 139 mile range in a five cycle test. Extrapolating from that, then a 50 kWh battery pack might have a 174 mile range in that car.

OK, 174 miles, divided by 5, gives ~35, which multiplied by 6 comes to about 208 miles... Again, presuming a 20% smaller vehicle. But this is still at 'Drive Like a Grandma' speeds that the EPA uses for testing.

No matter how I look at it, I cannot find a way to drive at constant high speeds and still achieve high efficiency. This is why I continually say you can't have it both ways... Low capacity battery pack with high speeds to get long range. The math doesn't work.

Red Sage ca us | January 29, 2015

EPA EFFICIENCY
VEHICLE Wh/MILE
BMW i3 BEV 229.5
Fiat 500e 246.5
Tesla Model S 60 297.5
Toyota Prius 674.0
Interesting. You know... If you multiply the 674 Wh per mile that the Prius manages by 200 miles, you get ~135 kWh. Equivalent to 4 gallons of gasoline. Using that amount of energy, the other cars would have a very good range indeed.
135 kWh BATTERY PACK
VEHICLE RANGE
BMW i3 587
Fiat 500e 547
Tesla Model S 453

Grinnin'.VA | January 29, 2015

@ Red Sage ca us | January 29, 2015

Yeah. The main reason I'm on this is that I doubt there is a way to have a constant 80 MPH, while still getting a very good Wh per mile rating...

Tesla's claim is that with 19" wheels (etc.) the P85D has about a 224 miles at 80 mph. The S85D range at 80 mph is slightly higher.

No matter how I look at it, I cannot find a way to drive at constant high speeds and still achieve high efficiency.

I agree. It's a simple matter of physics. Air resistance increases rapidly at fast speeds. It simply takes more energy to push against that air resistance.

Red Sage ca us | January 29, 2015

Can you show me where you found that? I don't remember official numbers from Tesla Motors at 80 MPH. I did see some for 65 MPH though...

Grinnin'.VA | January 29, 2015

@ Red Sage ca us | January 29, 2015

Interesting. You know... If you multiply the 674 Wh per mile that the Prius manages by 200 miles, you get ~135 kWh. Equivalent to 4 gallons of gasoline. Using that amount of energy, the other cars would have a very good range indeed.

But of course, we don't have a 135 kWh Tesla battery.
I sure wish we did.

Go Tesla!

Red Sage ca us | January 29, 2015

Yeah. The more I look at the numbers... If Tesla Motors offered a 100 kWh battery pack for Model ☰ and a 135 kWh battery pack for Model S and Model X... They wouldn't need to upgrade capacity any further until 2020 or later.

carlgo2 | January 29, 2015

How about something unusual like a 60+ kWh standard size and a 48 kWh as a cost delete option? This is arse-backwards, but would allow a lower cost version for those with home chargers and intended local use. It might allow for a \$35K price while it would seem very difficult to meet that target with a big S-class battery.

JeffreyR | January 30, 2015

Quick question: are we betting on what's actually in the pack or what is labelled on the back of the car?

It seems brick protection should already be taken into account in the number advertised and we should not need to to do extra math to figure out what the pack contains that we can actually use.

Put another way, we could guess 6840 '18650' cells will fit into a Model ≡. Trouble w/ this guessing game we would have to wait for a teardown before we know the answer.

Grinnin'.VA | January 30, 2015

@ cmcnestt | January 29, 2015

Tesla can't make 100M cars per year, it needs the rest of the industry to electrify the automobile.

My prediction is that "the rest of the industry" will not take BEVs seriously until they feel a serious drop in their sales numbers for their best selling models. Given Tesla's announced intentions for the M3, it seems to me that that will not happen until after 2020.

Red Sage ca us | January 30, 2015

JeffreyR wrote, "It seems brick protection should already be taken into account in the number advertised and we should not need to to do extra math to figure out what the pack contains that we can actually use."

I've gotten used to it. This is like Ford calling it a Mustang 5.0 for years, when the car only had a 4.9 liter displacement. Or Ford saying that motor had 220 HP, but not telling anyone that was the motor, by itself, on a workbench, with nothing else attached to it, after being balanced and blueprinted by engineers in a laboratory setting, and that in the car it only had 195 HP. It is also like someone telling you a computer has a 2 TB hard drive, but they don't mention that 500 GB is taken up by the operating system, a bunch of nagging bloatware that will never do you any good, and a backup image of the same, so that you only have 1.5 TB available for use.

So yeah... A Tesla Model ☰ 135 might be something with only 109 kWh counted toward its EPA range, but would still only have ~122 kWh total available for driving. Or, if I were in charge, the Tesla Model ☰ 135 would actually be a vehicle with a 150 kWh battery pack... By the way -- I'm not in charge.

;-)

JeffreyR | January 30, 2015

@Red Sage

Good point. I remember some posts by you a while back theorizing that the packs already contained fewer cells and they just kept the same rating or maybe limited them in sw like the 40 kWh faux option.

I took that too far and hypothesized a 45 kWh pack. Wish I were more awake to volkerize that thread. A couple quick points you made then apply to this thread.

1) 20% smaller does not mean 20% lighter (JBS's comments on steel frame to save costs)
2) 200 "real-world miles of range" likely translates to EPA-5 rating, so they will need a bit of padding beyond the "cruising range" often quoted.

I like starting at 60 kWh as a base w/ denser, lighter battery pack. Upgrades will include 'D' dual-motor AWD, 'P' Performance, and 85 kWh battery pack. The high-end Gen II models will get bumped up to the next notch. An 85 kWh base and a this-one-goes-to-eleven 111 kWh upgrade.

The active cooling and control software will benefit from having the same capacity as the existing battery.

Red Sage ca us | January 30, 2015

A little something I wrote elsewhere, about the Model S, but similar to my thought process regarding Model ☰:

I typically look at the cost in terms of Tesla's expense, then work from there to determine the possible price for a Customer. We don't actually know Tesla's cost per kWh on battery packs, but it has been estimated as low as \$180 to as high as \$240 or so over the past year... It is presumed that with the opening of the Gigafactory, their expense will drop by at least 30%. So, that means a cost reduction to a range of perhaps \$126 to \$168 per kWh. Thus, a 135 kWh battery pack might cost Tesla Motors between \$17,010 and \$22,680 to make.

JB Straubel has said that the cost of the battery pack represents perhaps 25% the cost of the car. That is most likely 25% of the retail cost, but might be 25% of Tesla's cost to build the vehicle. Let's look at it both ways, shall we? So this makes for either: 1) a range of \$68,040 to \$90,720; or 2) a range of \$90,720 to \$120,960 as a retail cost for the 135 kWh Model S. Either way, it would be doable once the Gigafactory comes online.

Continuing the same theme:

I remain certain that Tesla Motors must have a minimum 60 kWh battery pack in the Model ☰. I know that all that is said is a 20% reduction in 'size' as compared to the Model S. But I reiterate that falls precisely in line with the statement that Generation III cars will combat the BMW 3-Series in the market. Those cars happen to weigh precisely 80% as much as a Tesla Model S.

At \$126 to \$168 per kWh, a 60 kWh battery pack would cost Tesla Motors \$7,560 to \$10,080 each to build. Assuming that is 25% of the retail price, the car would have an \$30,240 to \$40,320 MSRP, or thereabouts. If it is instead 25% of the build cost, and Tesla wants to achieve a 15% margin per vehicle, the MSRP would rise to a \$35,576 to \$47,435 range.

Since I have predicted this car would have a \$34,900 list price, that means working backward... A \$29,665 build cost... With a \$7,416 to \$8,725 battery pack cost... Meaning a ~\$124 to ~\$145 per kWh target.

It also means that my dream of it being a 100 kWh car at that price point will require some serious hard work. ~\$74 to ~\$87 per kWh seems nigh impossible. Even I understand that much.

Yet, if there were an 8% improvement in energy density each year since the end of 2009... Of the battery design that was used in Model S 85 beginning in 2012... Then over the five years through 2014, a similar number of 18650 battery cells could potentially allow about a ~129 kWh capacity. Thus, a ~22% reduction in cell quantity would allow a 100 kWh battery pack at lower weight than the 85 kWh was... And a 30% reduction in battery cell cost due to a modified format and production at the Gigafactory would reduce costs further.

Not as low as I would like, but to a range of ~\$98 to ~\$130 per kWh. I suppose that will have to do. For now.

;-)

JeffreyR | January 31, 2015

My math: 85-60=25 so next notch is 85+25=110 and then Elon would like the Spinal Tap reference to get to 111. It just looks cooler! ;^)

Probably really should have just stuck to 110. But you can tell from my overall fuzziness in wording it was a bit late for my previous post.

You could also do the math using proportions. Then the next notch is 120. The reason I did the next notch using sums (beyond late night excuses) is that most folks would see it that way not the proportional way. They are lazy too. Also 110 is less expensive than 120 and therefore more profitable. But we're talking Tesla not some trickster. So other than the geek factor of 111, 120 is probably a better number.

But I think my other post about the individual cells may be a better way to do the math though.

What is the rating of the cells? How many will fit into a Model ≡ pack? What is the overhead? How much do you round off to get to a number that ends in 5 or 0?

I like your optimistic 135kWh battery pack idea. It means more range and your cost-based analysis seems sound. I wonder if they can make it work.

Too bad Tesla is a public company. If they were private Elon could go out and throw down a challenge like, "The next Model S battery pack will get 400 miles of 'real-world' range!" Depending on how/when he did it, it might cause a bit of a sales 'blip' though.

Grinnin'.VA | January 31, 2015

For a reference, the 2015 Prius claims a cruising range of over 600 miles. IMO, one-third of that for the G3 would disappoint most prospective buyers.

Red Sage ca us | January 31, 2015

It depends upon which is more important to Prius buyers:

1) The distance they drive before stopping for gas again...

~*versus*~

2) The prospect of never stopping for gas -- ever again.

Brian H | January 31, 2015

Gas cruisers like the Prius will gradually become less and less relevant. Who cares how much gas a car can burn?