Extent of Tesla's battery advantage

[RobStark]

It seems to me VW's plan is to drag their feet into the inevitable electrification of the automobile as long as possible but get through the transition before GM and Toyota. Even if they trail Renault-Nissan and BMW by a few years.

This probably avoids angry shareholders today and bankruptcy in the future.

But not a very good plan if the goal is to be the leading automobile company in 2030 and beyond.

 

[yesla]

I guess the missing link here is not just being price competitive with Tesla with cell cost but also capacity.
Tesla can make 500K cars with GF when fully operational, Audi will have to find a pretty committed supplier that can bid for and supply all the necessary batteries to compete on both price and volume.

It took a strong partnership with Tesla and Panasonic to make this work. It will take a looooong time before the market has enough demand for battery vendors to invest all the capex to expand capacity to meet the global demand for EVs. BYD may have already started to compete with GF, but there is much more room to grow for all the auto manufacturers.

Not to mention, the limiting factor is battery cell if auto manufacturers are seriously make capable EVs. Therefore, it will be the auto manufacturers who will be bidding for the batteries initially - high capacity batteries are especially sought after and will cost much more.

 

[32no]

From my understanding, the Audi R8 e-tron has a 92kwh battery that weights 600 kg. Tesla Model S has a 85kwh battery that weights 544 kg.

92000 / 600 = 153.33 wh/kg

85000 / 544 = 156.25 wh/kg

Am I missing something?

Good points in you post, and interesting conspiracy about Samsung actually using Tesla cells, but your information for the energy density of the Model S is wrong. The Model S battery weighs 1323 lbs (600kg), not 1200 lbs (544 kg), which I think is an estimate.

Anyway, if Samsung is building Tesla cells, they would be using Tesla's patents, which means we will get a precedence for the in good faith clause. I bet you we will find this out in some sort of press conference, and "in good faith" would mean that Tesla gets a huge PR win.

 

[JRP3]

Good points in you post, and interesting conspiracy about Samsung actually using Tesla cells, but your information for the energy density of the Model S is wrong. The Model S battery weighs 1323 lbs (600kg), not 1200 lbs (544 kg), which I think is an estimate.

I don't see that as definitive. From your source:

Based on a comparative analysis against components from rival luxury sedans such as Porsche’s Panamera and BMW’s M5, we can approximate the distribution of weight across the following Tesla Model S assemblies:

The real question is what is the cell level density of the VW cell compared to Tesla. Audi may have saved some battery weight in packaging, by using exotic, expensive materials, driving their pack costs higher.

 

[Robert.Boston]

I guess the missing link here is not just being price competitive with Tesla with cell cost but also capacity.
Tesla can make 500K cars with GF when fully operational, Audi will have to find a pretty committed supplier that can bid for and supply all the necessary batteries to compete on both price and volume.

It took a strong partnership with Tesla and Panasonic to make this work.

This is a key point, IMO. Tesla is controlling battery costs by making a substantial commitment to build capacity. VW sounds like it plans to buy "spot market" batteries. No battery company will spend billions to upgrade its plant without a supply commitment from a customer.

What this really tells me is that VW doesn't see itself selling meaningful volumes of EVs in the foreseeable future.

On a non-battery angle, VW's assertion that it will use many power trains in the same basic car tells me that its EVs won't be designed to take advantage of the flexibility of a BEV drivetrain. I'll guarantee that the result has a lot of wasted space and worse driving dynamics than Tesla's offerings.

 

[evme]

Good points in you post, and interesting conspiracy about Samsung actually using Tesla cells, but your information for the energy density of the Model S is wrong. The Model S battery weighs 1323 lbs (600kg), not 1200 lbs (544 kg), which I think is an estimate.

Anyway, if Samsung is building Tesla cells, they would be using Tesla's patents, which means we will get a precedence for the in good faith clause. I bet you we will find this out in some sort of press conference, and "in good faith" would mean that Tesla gets a huge PR win.

While I might agree with you that 1200 lb (544 kg) might be rounding, I will also argue that 1323 lb (600 kg) is also a rounding. So the battery pack weight is maybe somewhere in between. I would also estimate the Audi's claim of 600 kg is also rounded.

As far as patents goes, it gets a bit complex. While Tesla may be making their patents available, Panasonic is not. But it is possible that Samsung is licensing from Panasonic the required patents. Nothing unusual. But as far as an announcement might depend on the NDA agreements they have in place.

 

[jerry33]

While I might agree with you that 1200 lb (544 kg) might be rounding, I will also argue that 1323 lb (600 kg) is also a rounding. So the battery pack weight is maybe somewhere in between. I would also estimate the Audi's claim of 600 kg is also rounded.

Perhaps the 544 kg is without the aluminum tank armour on the bottom.

 

[stopcrazypp]

The problem is that it isn't what Tesla had in 2012. Tesla had an energy density of 141.67 wh/kg in 2012, and using the updated Roadster figures, we get an energy density of 155.56 wh/kg. Audi claims 154 wh/kg energy density and is supposedly using the same 18650 cells as Tesla except from Samsung instead of Panasonic.

I would like to point out a big caveat, which is that the updated Roadster uses less energy dense cells than the Model S does. If it used the same cells as the Model S, the gap would be even wider. I imagine a large part of the Model S pack's weight is the extra overhead of also functioning as a structural member and a shield.

From the 92kWh and 7,488 cells, you can calculate the r8 cells are 3300mAh-3400mAh (depending on if you assume 3.6V or 3.7V cells).

Other things to keep in mind: VW has a battery contract with Panasonic (for its hybrids), and also Martin Eberhard (one of Tesla's founders) had a stint in VW where he pushed heavily for 18650 based packs.

 

[evme]

Perhaps the 544 kg is without the aluminum tank armour on the bottom.

I doubt it. Though it most likely does not include the aluminum deflector and titanium shielding added after. Though I doubt they add that much weight.

I think it is the product of rounding, the battery pack is most likely under 1250 lb (567 kg) but over 550 kg. This way if you round it in lb it will get you 1200 lb but if you round it in kg it will get you 600 kg. So somewhere between 550 - 567 kg.

I would like to point out a big caveat, which is that the updated Roadster uses less energy dense cells than the Model S does. If it used the same cells as the Model S, the gap would be even wider. I imagine a large part of the Model S pack's weight is the extra overhead of also functioning as a structural member and a shield.

From the 92kWh and 7,488 cells, you can calculate the r8 cells are 3300mAh-3400mAh (depending on if you assume 3.6V or 3.7V cells).

Other things to keep in mind: VW has a battery contract with Panasonic (for its hybrids), and also Martin Eberhard (one of Tesla's founders) had a stint in VW where he pushed heavily for 18650 based packs.

As far as what cells they have, well this site claims:

Whereas the earlier R8 e-tron drew its electric energy from a 48.6kWh lithium ion battery, the new one gets a much larger 91.0kWh unit. The cells it uses also operate at a higher 3.6 amperes compared with 3.2 amperes previously, giving the e-tron greater discharge ability for better accelerative performance

2015 Audi R8 e-tron prototype review | Autocar

Though other sources say 92kwh so not sure but it might be a typo.

But if we look at it: 92,000wh / 7488 cells = 12.28632478632479wh per cell.

Assuming consistent 3.6 amp discharge it would be 3.41286799620133 volts.

So either the cells are ~3.4v (Panasonic 4.0Ah cells are also 3.4v). Or they messed up amps and volts and it is ~3400mah cells at 3.6v.

 

[renim]

.... VW sounds like it plans to buy "spot market" batteries. No battery company will spend billions to upgrade its plant without a supply commitment from a customer....

NO Autocompany buys li-ion EV battery on the spot market. the nearest to that is Renault or Toyota.

why didn't Tesla use LG or SDI cells when they were severely cell restrained?
ans, it was too expensive, and too slow to run all safety tests

 

[32no]

I would like to point out a big caveat, which is that the updated Roadster uses less energy dense cells than the Model S does. If it used the same cells as the Model S, the gap would be even wider. I imagine a large part of the Model S pack's weight is the extra overhead of also functioning as a structural member and a shield.

From the 92kWh and 7,488 cells, you can calculate the r8 cells are 3300mAh-3400mAh (depending on if you assume 3.6V or 3.7V cells).

Other things to keep in mind: VW has a battery contract with Panasonic (for its hybrids), and also Martin Eberhard (one of Tesla's founders) had a stint in VW where he pushed heavily for 18650 based packs.

How do you know the updated Roadster uses less energy dense cells than the Model S does? This contradicts what we know about the new Roadster, which fits 70 kWh in "the same package as the original battery (in 2008)". Moreover, the new Roadster has a cell that has 31% more energy. It's been 7 years since the original Roadster was introduced, which would work out to approximately 3.93% improvement every year, which is in line with the improvement between the original Roadster (53 kWh and 450 kg, or 117.78 wh/kg) and the Model S (85 kWh and 600 kg, or 141.67 wh/kg), an improvement of 20.28% or ~4.1% per year (4.5 year difference).Therefore, I think it is safe to conclude that the updated Rodaster uses MORE energy dense cells than the Model S does, or at the very least, the same energy density.

 

[Auzie]

This is a key point, IMO. Tesla is controlling battery costs by making a substantial commitment to build capacity. VW sounds like it plans to buy "spot market" batteries. No battery company will spend billions to upgrade its plant without a supply commitment from a customer.

What this really tells me is that VW doesn't see itself selling meaningful volumes of EVs in the foreseeable future.

On a non-battery angle, VW's assertion that it will use many power trains in the same basic car tells me that its EVs won't be designed to take advantage of the flexibility of a BEV drivetrain. I'll guarantee that the result has a lot of wasted space and worse driving dynamics than Tesla's offerings.

Battery is Tesla's competitive edge, or BEV's competitive edge over ICE technology. It lies in the heart of the product, all other components are more or less easily accessible to any competitor.

My bet is that whoever wins the battle of batteries will win the technology war.

The battle of batteries will be won by getting all relevant batteries parameters, including supply, under strict business control.

VW and other ICErs have a huge shareholders hurdle to overcome if they wish to seriously engage in a battery battle. I find it highly unlikely that they are able to overcome that hurdle.

Checkmate.:wink: By Tesla

 

[JRP3]

How do you know the updated Roadster uses less energy dense cells than the Model S does?

70,000Wh / 6831 cells = 10.25 Wh/cell
85,000Wh / 7104 cells = 11.97 Wh/cell

 

[evme]

70,000Wh / 6831 cells = 10.25 Wh/cell
85,000Wh / 7104 cells = 11.97 Wh/cell

I have not looked into the details of new roadster yet but you are talking about energy density by volume. The discussion here has been about energy density by weight.

 

[JRP3]

They tend to track together unless there is a significant change in chemistry.

 

[stopcrazypp]

I have not looked into the details of new roadster yet but you are talking about energy density by volume. The discussion here has been about energy density by weight.

The cell weight does not vary much versus capacity for the same cell chemistry. From JRP3's number's the Model S cells have 17% more energy than the updated Roadster.

The Roadster cells track well with the 2900mAh NCR18650 which weighs 45.5g, the Model S tracks well with the 3350mAh NCR18650B which weighs 47.5g. The difference in weight is 4.4%, so the Model S cells are still significantly more energy dense than the updated Roadster's even by weight.

http://industrial.panasonic.com/ww/...teries/lithium-ion-batteries/cylindrical-type