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Haxster
Member
Yes. Four motors + zero differentials --> unprecedented torque control and effieiency.
Elon has said absolutely not, therefore, I think it is a certainty that a bigger battery option is right around the corner. Same thing for higher speed charging.
The current car has to pull back power to two wheels when one of them starts spinning. By having power directly to each individual wheel, you can get just a fraction more acceleration from the same amount of grip.
And, of course, it opens the door to all sorts of interesting torque vectoring and active handling adjustments. That's why all of the electric supercars have been going that direction. For Tesla, I'm really thinking a three motor makes sense, actually - they get most of the benefits from going to separate rear motors while keeping commonality and lower costs up front. (The front wheels are less likely to be spinning under hard acceleration due to weight transfer, so there's less benefit there.)
If they can design a packaging that lets them use two of the smaller front motors side by side, it would also let them reduce the number types of motors they build - eliminate the last remaining RWD model, switch the PxxxT/Q cars to dual rear motors, and stop building the big motors.
The weight transfer is to the rear, so the front wheels are more likely to spin. On my car the torque on the front motor reaches its maximum first and begins to decrease as the rear torque continues to increase.
Oops. I expressed that poorly. You're right, the front wheels will spin at a lower torque level.
What I was trying to say is that having individual control over the rear wheels is more useful because you can get more acceleration out of optimizing them, precisely because they have more grip.
Yeah, I agree with that. The rear torque peaks at 600 Nm while the front is only 300 Nm. The gains wouldn't be huge, though. It's only the difference between static and sliding friction for the tires on road, similar to what a locking differential would provide.
Pretty much - with the added benefit of being able to torque vector for better steering/handling and stability control.
Not a large difference, no, but with the P100DL already putting state of the art road tires on the friction limit all the way to 60, little gains are all that's possible until better tires come along, unless you put on semi-slicks...
These guys seem to agree with you.
Magna shows Tesla that three motors are better than two when it comes to corners
Of course there will be larger batteries. Otherwise, what will entice a current Tesla owner to trade for a newer model? I have a S85D. Moving to the S100D isn't a large enough range increase to justify the cost of the trade. With Lucent supposedly coming out with a 130KW battery option, Tesla will not be left behind. By 2020 Porsche, Audi, BMW, Toyota, Dyson, Mercedes, etc., will have caught up to Tesla, where they are today. In order for Tesla to maintain their lead, they will have to have a 130 KW battery or larger.
Not wit hthe current 18650 cell. The next larger battery will use the new 21700 that are in the 3. They have 33% more capacity per cell, making a P133 possible with the same amount of cells as current (though that would be a larger pack), but we'll probably see familiar capacity packs that weigh less first. The increased cell size means we'll probably also see a dramatic refresh soon, rather than the small cosmetics we've had so far. The frame will need to fit the new battery and I doubt it'll be retrofit capable.
If they have to do substantial engineering work like you seem to be suggesting, I don't think it'll happen anytime soon. Tesla has higher priorities for their workforce, and once the 3 ramp happens they don't need S/X sales to keep growing (not that they'd be unhappy if they do.)
Based on this perspective on the company as a whole, my bet is that any new versions we see if the S and X will be minor modifications to the existing cars, not a major change (which is not to suggest that Tesla will be willing to retrofit the changes.)
New interiors, New motors, New batteries, but all fitting into the same architecture and structure.
Eventually solid state batteries will be here with all the advantages they can bring (both safer and higher energy density), but the prototypes are only in labs now. Unless Tesla has been working in secret on something and is way ahead of the publicly announced progress, we probably won't see solid state cells until the 2020s, possibly not until mid-decade. There are a lot of steps between the lab and full production and they aren't out of the lab yet.
It is possible Tesla might see a 20% improvement in energy density when they start putting 2170s in the S/X line, which could mean a jump to 120 KWh for the top of the line. I expect a major refresh sometime early next year, though it may be coming sooner with Tesla's announcement of the end of free supercharging at the end of this month instead of the end of this year as they had initially announced. I definitely expect the interior of the S and probably X to get a facelift. I expect some of the nicer features from the 3 to be ported over while at the same time being nicer than the current interior. I hope they keep the two screen layout, I don't like the center screen only of the 3.
Elon has said there are no plans to go beyond 100 KWh for a while, but that's in Elon time, which is very flexible. The GigaFactory is ramping up car battery production now and they need to stay ahead of the Model 3 ramp up curve, but there will come a point where 2170s for the cars will have enough production to support the Model S and X too and that's when Tesla will likely switch over to the new cells. The Model 3 will be a priority and they will need to make sure Model 3 production will never be disrupted for a shortage of batteries and there are enough to cover the S/X lines before they switch over. They will likely switch the large or small pack first, then switch the other after a while like they did with the 2nd gen 18650s and I believe they will be doing with the small packs (getting 100 KWh pack modules for a new 85 or 90 pack as the entry model) soon.
Once the GF is producing enough to support all Tesla production, Panasonic can shut down their Asian factories to switch over to 2170s, or supply other car makers from Asia depending on Tesla's needs.
I strongly doubt there will be a quad motor version of the Model S/X. The P100D is kind of a gimme on top of the 100D. Change out the back motor for the RWD car motor, change the fuse on the pack, and do some firmware changes and the car is a super car. The P100D is a vastly profitable car for Tesla. It costs them almost nil over the 100D to make and they charge a hefty premium.
For the standard cars, there is little gain from quad motors. The dual motor design for the S/X added range as well as performance, so it was the logical way to go, but quad motors won't gain much of anything for the regular sedans and they won't add enough to the Performance cars to make it worthwhile. If Tesla ever comes out with a quad motor, it will be in the next gen Roadster, but even there I don't think it will happen.
Tesla started up market because that was where the money was for their first two generations of cars, but Tesla's long term plan is to become the next Toyota not the next Porsche. If they happen to have some high performance cars that come out of other projects, they will make them, but they aren't going to set out to make super cars. The P100D will not be the king of the drag strip for long, there are electric super cars coming that will eat its lunch, but I don't think Tesla will really care. Bugatti or Lamborghini can sell a handful of cars to a year to some super wealthy people, but Tesla will be putting millions of cars into the driveways of people all around the world.
If a super car company goes all electric, that is a novelty. Most of those cars will be driven less than 1000 miles a year. Put 1 million electric cars on the road every year with an average of 12000+ miles a year and you will literally be changing society. Even if autonomous Ubers don't happen, if the middle class goes electric, that will be a major shift.
So a quad motor car is going off in the wrong direction for Tesla. If and when the next gen Roadster happens, maybe, but don't hold your breath. Elon has gone back and forth on the Roadster a number of times, though with the current referral program maybe it will happen. Who knows.
It is possible Tesla might see a 20% improvement in energy density when they start putting 2170s in the S/X line, which could mean a jump to 120 KWh for the top of the line. I expect a major refresh sometime early next year, though it may be coming sooner with Tesla's announcement of the end of free supercharging at the end of this month instead of the end of this year as they had initially announced. I definitely expect the interior of the S and probably X to get a facelift. I expect some of the nicer features from the 3 to be ported over while at the same time being nicer than the current interior. I hope they keep the two screen layout, I don't like the center screen only of the 3.
Elon has said there are no plans to go beyond 100 KWh for a while, but that's in Elon time, which is very flexible. The GigaFactory is ramping up car battery production now and they need to stay ahead of the Model 3 ramp up curve, but there will come a point where 2170s for the cars will have enough production to support the Model S and X too and that's when Tesla will likely switch over to the new cells. The Model 3 will be a priority and they will need to make sure Model 3 production will never be disrupted for a shortage of batteries and there are enough to cover the S/X lines before they switch over. They will likely switch the large or small pack first, then switch the other after a while like they did with the 2nd gen 18650s and I believe they will be doing with the small packs (getting 100 KWh pack modules for a new 85 or 90 pack as the entry model) soon.
Once the GF is producing enough to support all Tesla production, Panasonic can shut down their Asian factories to switch over to 2170s, or supply other car makers from Asia depending on Tesla's needs.
I strongly doubt there will be a quad motor version of the Model S/X. The P100D is kind of a gimme on top of the 100D. Change out the back motor for the RWD car motor, change the fuse on the pack, and do some firmware changes and the car is a super car. The P100D is a vastly profitable car for Tesla. It costs them almost nil over the 100D to make and they charge a hefty premium.
For the standard cars, there is little gain from quad motors. The dual motor design for the S/X added range as well as performance, so it was the logical way to go, but quad motors won't gain much of anything for the regular sedans and they won't add enough to the Performance cars to make it worthwhile. If Tesla ever comes out with a quad motor, it will be in the next gen Roadster, but even there I don't think it will happen.
Tesla started up market because that was where the money was for their first two generations of cars, but Tesla's long term plan is to become the next Toyota not the next Porsche. If they happen to have some high performance cars that come out of other projects, they will make them, but they aren't going to set out to make super cars. The P100D will not be the king of the drag strip for long, there are electric super cars coming that will eat its lunch, but I don't think Tesla will really care. Bugatti or Lamborghini can sell a handful of cars to a year to some super wealthy people, but Tesla will be putting millions of cars into the driveways of people all around the world.
If a super car company goes all electric, that is a novelty. Most of those cars will be driven less than 1000 miles a year. Put 1 million electric cars on the road every year with an average of 12000+ miles a year and you will literally be changing society. Even if autonomous Ubers don't happen, if the middle class goes electric, that will be a major shift.
So a quad motor car is going off in the wrong direction for Tesla. If and when the next gen Roadster happens, maybe, but don't hold your breath. Elon has gone back and forth on the Roadster a number of times, though with the current referral program maybe it will happen. Who knows.
It's not battery capacity that's important - it's the range, coupled with the charging network to support non-local driving. So a simple comparison of battery pack sizes between manufacturers or models isn't that important - the Model 3 will have use less energy per mile, so it can get over 300 miles of range with a smaller battery pack than the S or X.
While conceptually a longer range seems useful, in practice, there are diminishing returns with larger and larger battery packs, because a quickly decreasing percentage of owners will ever actually need that much range - shrinking the potential market for longer range cars, with higher prices.
With more competition hitting the market in the next few years and Tesla cars already available with 300+ mile range and a supercharging network able to support shorter range cars, it may make more sense for Tesla to focus on driving down the costs of their battery packs (and cars) and improving performance (energy efficiency), than to continue building larger and larger battery packs for a smaller and smaller market.
While conceptually a longer range seems useful, in practice, there are diminishing returns with larger and larger battery packs, because a quickly decreasing percentage of owners will ever actually need that much range - shrinking the potential market for longer range cars, with higher prices.
With more competition hitting the market in the next few years and Tesla cars already available with 300+ mile range and a supercharging network able to support shorter range cars, it may make more sense for Tesla to focus on driving down the costs of their battery packs (and cars) and improving performance (energy efficiency), than to continue building larger and larger battery packs for a smaller and smaller market.
In this thread and others there is not too much commentary about efficiency improvements that extract more range from a given battery size. Several Tesla engineers, including JB, have stated repeatedly that they expect greater proportional benefits from wiring, inverter, motor, BMS and passive drain than they expect from battery improvements, at least until a major technical breakthrough in some new energy storage solution comes along.
Thus, we could expect 100's might well soon have the performance and range that we heretofore have imagined would necessitate 120 or so. As Magna, Delphi and others apparently think, multi-motors with torque vectoring will provide improved stability and traction. Not much discussed is the possibility that such an approach might reduce weight and increase efficiency.
I am not predicting anything. Still, I'm convinced that we are on the cusp of huge advances in efficiency and other benefits. The pace of innovation is accelerating. We need not be completely devoted to the notion that more stored energy with higher power density too is the only way to give us more range and performance.
Thus, we could expect 100's might well soon have the performance and range that we heretofore have imagined would necessitate 120 or so. As Magna, Delphi and others apparently think, multi-motors with torque vectoring will provide improved stability and traction. Not much discussed is the possibility that such an approach might reduce weight and increase efficiency.
I am not predicting anything. Still, I'm convinced that we are on the cusp of huge advances in efficiency and other benefits. The pace of innovation is accelerating. We need not be completely devoted to the notion that more stored energy with higher power density too is the only way to give us more range and performance.
The same type of logic you're using to dismiss the four motor can be used to support a three motor, though.
As of this week, the P100DL is the only car still using the old larger rear motor.
How much does it cost Tesla to hold the production line open for this part solely for the performance model? (and spares for replacement when they can't rebuild, though I think those are very rare.)
If they can use two of the existing small motors and reduction boxes with minimal new parts it might be cheaper overall to do that, while at the same time giving higher performance and letting Tesla explore the brave new world of torque vectoring...
kvandivo
Member
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Minor point, but just to be clear, unlimited supercharging is continuing past the end of the month. The $1000 credit is going away, but unlimited supercharging is continuing. End date is really unknown. All we know from the wording is that the referral order has to be placed by the end of Jan 2018.
Referral Program
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Minor point, but just to be clear, unlimited supercharging is continuing past the end of the month. The $1000 credit is going away, but unlimited supercharging is continuing. End date is really unknown. All we know from the wording is that the referral order has to be placed by the end of Jan 2018.
Referral Program
X Fan
Active Member
People are used to Moore's Law which did increase density and decrease costs at a fairly steady rate, but there were fewer variables to Moore's Law. Primarily it was driven by the technology to etch integrated circuits smaller. As time went on higher and higher frequency light needed to be used. They started in the visible light spectrum and ended up in the x-ray spectrum.
Batteries are a much more complex problem. There are about 8 different factors that need to be weighed with each chemistry and tweaking the chemistry might improve one factor, but make the others worse and all that needs to be tested before production. Production might need to change radically for different chemistries too.
The average might be about 7% a year, but it really moves in fits and starts. It might change 12% one year, 0% the next, and 10% the year after that. The average is around 7%, but it isn't linear.
I believe the agreement was for 1 billion cells and they are around that now. They were expected to hit that target around late 2017. In any case, Tesla has made Panasonic the world's largest li-ion battery maker and a huge percentage of the company's annual income comes from Tesla alone. They are also anticipating a massive growth in volume with Tesla over the next few years.
With a customer like that, volume contracts like the one for the 18650 are open to renegotiation at any time.
