Tesla Model 3

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If we are talking about Roadster 2 pack, so today TMS/X 100kWh pack have volumetric density ca 160 Wh/kg and TM3 is also very close to this value. I am awaiting that 5.5 Ah cells in 21700 format will enter the market till 2020, so there will be ca 10 % increase in energy density against today available 5 Ah cells. Also new methods of packaging and thermal management can increase "big" 200 kWh pack density up to 200 Wh/kg. So 1000 kg seems to me to be achievable at that time. Yes it is still lot of mass but Roadster 2 will have advanced three motor configuration with torque vectoring. This kind of powertrain have possibility to almost "switch off" the problem of high mass in modern electric vehicles. It will be very soon demonstrated by Audi e-tron Quattro.
 
Cephalotus said:
Arlo1 said:
A blanket statement saying that 200kwh in a single car battery is bad for the environment has no meaning as we don't know the production process of said future battery. If it's made at a solar power gigafactory than it might be 100% environmentaly friendly.

It is bad because a 200kWh battery will weight 700kg+ and that weight will cause more consumption It also casues more structural weight for the vehicle, more road damage, it will consume more space because it will be larger and so on...

I admit this is more a problem in Europe than in the US where everything is bigger.

A modern battery cell will last 2.000 to 5.000 full cycles. A 200kWh battery in a low efficiency vehicle will be able to drive lets say 600km/cycle.

so the cells could to up to 3 million km, which nobody will use on the car. So the cells will die of age, most of their potential will be unused.

No matter the energy consumption, the resources needed for a 200kwh are double the resources needed for a 100kWh battery and the main ecological problem comes from copper and aluminum, the most critical element will be cobalt. The electricity source for building the cells itself has an impact, but not a huge one.
And if a look at the Gigafactory 1 I see little public transport, no bikes, but hundreds of large cars from the employees that often drive many, many miles day per day to work somewhere in the desert.
Would be interesting to see a calculation on that.

Cobalt is scare and why waste it for 200kWh batteries for s sports vehicle that you can not allowed to drive at half its top speed in 98% of the world. It's just a Fetish product. That#s fine, but doen't call it "environmental friendly", it's a symbol on stupid waste of resources by Hiomo sapiens.

In my opinion a much wiser design would be a 100kWh battery that can be charged at 300-400kW of power.

Make a efficient vehicle that runs on 25kWh/100km at highway speed (98% of the world) and you are perfectly fine with 3 hours driving and 20 minute charging. Make good high quality cells and you can do that "forever".

An exception is the German Autobahn, if you want to drive 200km/h your 100kWh battery will only last for 60-90 minutes of driving, but that's 2% of the world and even here only 2% of the Autobahn drivers will drive 200km/h, most drive significantly slower.

Ok there is a few statements very wrong.
#1 you don't know any of the specs other then its 200kwh. You don't know weight size or cycle life of chemistry or how it will be produced you don't even know if its a magic cell that doesn't age.
#2 MOST road damage is caused by the big trucks and many of them are hauling fuel for the ICE cars. Also a lot of damage is caused by ICE cars and their heat and leaking of oil and gas etc. Have you ever looked at the pavement at a 7/11 parking lot?
#3 This is a low volume production car and the cars it will be replacing BURN insane amounts of fuel to produce inferior results.
#4 look at the bigger picture. Joe Dickhead keeps talking about the new bugati he is about to order and says this and that then his buddy shows him the Roadster and he thinks hmm I do only want the Bugati for the numbers maybe I will get a Roadster in stead and this changes his outlook on EVs as a whole.. IN fact look at all the kids in school I remember when I was in elementary I wanted a Lamorgini Because at the time it was the most bad ass. But now look at all those kids and adults who think I want this even though they cant afford it.... When the average person sees a Roadster is the most bad ass supercar for about 1/10 the price they quickly realize hey maybe EVs are not so bad after all. This in turn helps many who can't afford a Roadster look at EVs they can afford and helps kick off the transition even faster.
 
Pajda said:
So 1000 kg seems to me to be achievable at that time. Yes it is still lot of mass but Roadster 2 will have advanced three motor configuration with torque vectoring. This kind of powertrain have possibility to almost "switch off" the problem of high mass in modern electric vehicles. It will be very soon demonstrated by Audi e-tron Quattro.

It may be possible to mitigate some of the deleterious effects of such a horrendously heavy on vehicle handling, but nothing can be done to mitigate the more serious effect on vehicle energy consumption every time it accelerates.
 
Punx0r said:
It may be possible to mitigate some of the deleterious effects of such a horrendously heavy on vehicle handling, but nothing can be done to mitigate the more serious effect on vehicle energy consumption every time it accelerates.

Well, some of the energy that is used to accelerate a heavy vehicle can be recouped on braking. But none of the added rolling resistance incurred due to high vehicle weight can be recovered.
 
Chalo said:
Punx0r said:
It may be possible to mitigate some of the deleterious effects of such a horrendously heavy on vehicle handling, but nothing can be done to mitigate the more serious effect on vehicle energy consumption every time it accelerates.

Well, some of the energy that is used to accelerate a heavy vehicle can be recouped on braking. But none of the added rolling resistance incurred due to high vehicle weight can be recovered.

Again we don't know its heavy its all PURE speculation!
 
Automotive batteries, including armor, cooling, bussing, etc. are not light. There is a significant cost associated with hauling around extra weight in a vehicle - hence the difference in efficiency between bicycles and electric cars. Doubling or quadrupling the amount of batteries carried around is not a zero impact effect. Whatever the weight, carrying unused extra range around with batteries is a significant cost, both in weight as well as investment and depreciation.
 
Arlo1 said:
Again we don't know its heavy its all PURE speculation!

It's a car. Of course it's heavy.

Cars have to be heavy because car drivers are such giant huevones.
 
It could be now that Elon has hands on the details of 21700 cell manufacturing that it could be this special release 200KWh roaster will have especially expensive lithium cells that have more cobalt etc in them then is typically considered financially viable, thus giving them super performance.

In a more theoretically fanciful look at lithium cells you can actually acheive 200KWh for around 1000KG if you use HK lipo.
I haven't actually thought about this much so maybe I am missing something here but..
https://hobbyking.com/en_us/multistar-high-capacity-6s-20000mah-multi-rotor-lipo-pack.html?mode=list
Minimum Capacity: 20000mAh
Configuration: 6S1P / 22.2V / 6Cell
Pack Weight: 2405g

So 20Ah x 22.2v = 444Wh
200,000 / 444 = 450 hk-lipo packs
450 x 2.405KG = 1082.25KG for 200KWh via HK lipo packs.

Cost (for the sake of it) USD $129.54 x 450 = $58,293 USD

The interesting thing is if you use a slightly smaller HK lipo pack the weight increases significantly.
https://hobbyking.com/en_us/multistar-high-capacity-6s-12000mah-multi-rotor-lipo-pack-1.html?mode=list
Minimum Capacity: 12000mAh
Configuration: 6S1P / 22.2V / 6Cell
Pack Weight: 1610g
So 12Ah x 22.2 = 266.4Wh
200,000 / 266.4 = 750 lipo packs
750 x 1.61KG = 1,206KG

Again I am not saying the new super 200KWh Tesla roadster is going to be made out of lipo packs but who knows whats possible for a car where money is no object type of thinking, maybe the whole battery pack will be wrapped in a graphene super protective diamond pouch or something of that nature so that its lighter and more fireproof, anything is possible when its the very best, maybe they even have hand chosen only the hardest working kids in the DRC to hand pick the very best looking cobalt rocks in the DRC before shipment and refinement process starts etc https://youtu.be/JcJ8me22NVs
 
billvon said:
Cephalotus said:
A modern battery cell will last 2.000 to 5.000 full cycles.
Li-ion batteries last 500 full cycles, 1000 if you baby them.

A NMC 333 automotive quality cell should last around 15 years and 5.000 cycles. Cycle life performance in NMC 622, NMC 811 and NCA is reduced, as far as I know. NCA has good calander life. LFP is quite a mixed bag, but mostly irrelevant for battery electric cars.
LTO can last more than 10.000 full cycles, but is to heavy and expensive for BEV

We are not talking about our consumer quality 18650 cells here.

Those batteries are already used for solar storage systems or for storage syystem in the primarey balancing market and there is usually a warranty on them (Ri and capacity) for many thousand cycles.
A solar home storage System battery has to survive 250 to 350 full cycles per year for minimum 10 years, better 15-20 years.

Similar for cells in electric busses. Those drive 300 full cycles per year minimum, many of them have more cycles and they are usually designed to last around 10 years.

We are not even talking about cells for hybrid vehicles which do not full cycles, but last hundredthousands to millions of partial cycles during their design lifetime.

The battery world is a bit bigger than just Tesla and their NCA cells from Panasonic. Even Tesla does not uses their model S cells in their Powerwall systems, because the Tesla S cells don't have good enough cycle life for that apllication.

The "technological advantage" of the early Tesla models (Roadster, S, X,...) has been that Tesla was willing to risk taking a cell with high energy denisty and low cost that has higher risc than NMC and shorter cycle life. They used so many of them to reduce cycle demands and reduce power demands per cell.
So far their approach has been a success. Established players have not be willing to take similar riscs with their early electric vehicles.
 
You cannot achieve 200kWh @ 1000kg using 750 Hobbyking lipo packs because it would contain quite a few dud packs and burst into flames before you'd finished assembling it, which would dramatically reduce the weight, but also the capacity.
 
TheBeastie said:
It could be now that Elon has hands on the details of 21700 cell manufacturing that it could be this special release 200KWh roaster will have especially expensive lithium cells that have more cobalt etc in them then is typically considered financially viable, thus giving them super performance.

My 700kg+ for 200kWh is based on 350Wh/kg for energy density of cells (which could be achievable in the future, especially for such a large pack that does not need to survive high C rates and many cycles) and the + is for the weight of the packaging which is unknown.

So yes, 1000kg or even more is a more realistic number for the entire 200kWh battery, at least before new technologies like LiS are available.

This makes building a 200kWh battery für a "sports car" even more problematic imho.
 
Teslas 100kWh pack only has 400kg of actual cells.
But we need a commercial, safe , complete pack....hence the extra 250kg in connections, cooling, electronics, packaging etc etc.
We have had 200-250 Wh/kg cell chemistry for nearly 10 years, but progress beyond that seems painfully slow ??
And the "new" 21700 Tesla cell is actually a step backwards in energy density. !
And for cycle life, very few commercial packs are allowed to use 100% DOD (which quoted cycle life data is based on) , most only using 80% of capacity with some only 70%. ..That dramatically increases cycle life.
Hence why EV manufacturers can comfortably offer 8+ yr warranties.
 
Cephalotus said:
TheBeastie said:
It could be now that Elon has hands on the details of 21700 cell manufacturing that it could be this special release 200KWh roaster will have especially expensive lithium cells that have more cobalt etc in them then is typically considered financially viable, thus giving them super performance.

My 700kg+ for 200kWh is based on 350Wh/kg for energy density of cells (which could be achievable in the future, especially for such a large pack that does not need to survive high C rates and many cycles) and the + is for the weight of the packaging which is unknown.

So yes, 1000kg or even more is a more realistic number for the entire 200kWh battery, at least before new technologies like LiS are available.

This makes building a 200kWh battery für a "sports car" even more problematic imho.

350 Wh/kg on cell level is way too optimistic in near future and especially in mass production. Realistic goal for 2020 is 300 Wh/kg. Even if there will be available such technology the car producers will sell it to customer in steps like 250, 280, 300 .. Wh/kg and between each step there will be at least one year pause
 
Cephalotus said:
A NMC 333 automotive quality cell should last around 15 years and 5.000 cycles. Cycle life performance in NMC 622, NMC 811 and NCA is reduced, as far as I know. NCA has good calander life. LFP is quite a mixed bag, but mostly irrelevant for battery electric cars.
LTO can last more than 10.000 full cycles, but is to heavy and expensive for BEV

The point is that you can have cell with 15 years and 5000 full cycles lifetime based on almost all known chemistries, but not with the high energy density. NCA, NMC, LFP and even LCO can be designed for this conditions but the volumetric density will be 350 Wh/l at best. If you need 700 Wh/l or more, you have to be satisfied with the life of 500 full cycles.
 
Pajda said:
350 Wh/kg on cell level is way too optimistic in near future and especially in mass production. Realistic goal for 2020 is 300 Wh/kg. Even if there will be available such technology the car producers will sell it to customer in steps like 250, 280, 300 .. Wh/kg and between each step there will be at least one year pause
There are cells out with 450Wh/kg, they could be considered exotic by now, but they apparently work on more affordable automotive version, named Apolo.
http://assets.solidenergysystems.com/wp-content/uploads/2017/09/08171937/Hermes_Spec_Sheet1.pdf
So, technology is there and progress is only accelerating historically.
 
Cephalotus said:
A NMC 333 automotive quality cell should last around 15 years and 5.000 cycles.
Yes, it should.

My first EV was a 2012 Leaf. Its NMC battery lasted 7 years before its range got so bad that it was unusable (<40 miles.) That's a loss of over 50% in 7 years.

So yes, NMC batteries SHOULD last a long time. But they don't. Hopefully they will improve with time.
Cycle life performance in NMC 622, NMC 811 and NCA is reduced, as far as I know. NCA has good calander life. LFP is quite a mixed bag, but mostly irrelevant for battery electric cars.
LTO can last more than 10.000 full cycles, but is to heavy and expensive for BEV.
Agreed.
We are not talking about our consumer quality 18650 cells here.
Right. In the Leaf we were talking about large format NMC cells.
Those batteries are already used for solar storage systems or for storage syystem in the primarey balancing market and there is usually a warranty on them (Ri and capacity) for many thousand cycles.
You might be talking about something very different here. Batteries for auxiliary grid services (voltage/frequency stabilization) are very high power - but very low energy. They have to last thousands of cycles because they can be cycled dozens of times a week. By reducing energy density (thicker electrodes, more electrolyte, thicker separators) that can be achieved.

Here, for example, we were working with an EV company that produced cells for racing. They could handle 50C charges and 100C discharges - and under standard charge/discharge cycles have lasted thousands of cycles. But their energy density was about a third of a standard 18650.

There's no free lunch.
 
billvon said:
Right. In the Leaf we were talking about large format NMC cells.

Yes the leaf cells had a Problem with high temperatures.

One or a few bad examples are no proof that the Claim is wrong. A PV modul lasts 30 years+, but there have been moduls around that got defective after 1 year. So what?


You might be talking about something very different here. Batteries for auxiliary grid services (voltage/frequency stabilization) are very high power - but very low energy. They have to last thousands of cycles because they can be cycled dozens of times a week. By reducing energy density (thicker electrodes, more electrolyte, thicker separators) that can be achieved.

Those Megawatt battery projects that I know in detail use charging rates around 1C.

They often use automative cells because those are quite cheap now.

Mercedes Benz energy uses the same battery moduls for the home storage systems as in their first electric cars. They give a warranty on 5000(?) full cycles afair.

I have been inside the factory and have seen the production lines.
 
Pajda said:
The point is that you can have cell with 15 years and 5000 full cycles lifetime based on almost all known chemistries, but not with the high energy density. NCA, NMC, LFP and even LCO can be designed for this conditions but the volumetric density will be 350 Wh/l at best. If you need 700 Wh/l or more, you have to be satisfied with the life of 500 full cycles.

So even more arguments against a 200kWh battery pack, isn't it?
 
Cephalotus said:
Yes the leaf cells had a Problem with high temperatures.
This particular Leaf was in coastal San Diego, an area known for its moderate temperatures.
One or a few bad examples are no proof that the Claim is wrong. A PV modul lasts 30 years+, but there have been moduls around that got defective after 1 year. So what?
Everyone I've talked to who had a 2011-2015 Leaf here has had a similar problem. Some better, some worse - one guy had a range of about 25 miles after five years; he finally gave up trying to get Nissan to replace his battery and bought another car.
Very few people I have talked to who has solar on their house has had to have panels replaced.
So yes, there's a difference.

Like I said, hopefully they will get better. But in my job I see breathless battery announcements about once a month. "New technology by X makes batteries last 5000 cycles! Doubles energy density! Charge in 90 seconds!" At this point I believe it when I see it.
Those Megawatt battery projects that I know in detail use charging rates around 1C.
If you are talking about the recent Tesla/Sonnen etc systems out there, those provide different services - load leveling/peak shifting/peak shaving and UPS functions. So they need larger capacities, and thus use different battery types. The Tesla system use 18650's - the Sonnen system uses LiFePO4.
Mercedes Benz energy uses the same battery moduls for the home storage systems as in their first electric cars. They give a warranty on 5000(?) full cycles afair.
Yep. It will be good to see them in operation so we can get some real-world data. (Such systems also provide a great way to recycle automotive packs that get below 70%.)
 
Cephalotus said:
Pajda said:
The point is that you can have cell with 15 years and 5000 full cycles lifetime based on almost all known chemistries, but not with the high energy density. NCA, NMC, LFP and even LCO can be designed for this conditions but the volumetric density will be 350 Wh/l at best. If you need 700 Wh/l or more, you have to be satisfied with the life of 500 full cycles.

So even more arguments against a 200kWh battery pack, isn't it?

No, higher capacity pack is always a benefit. There are several studies which says that the average driver travels ca 100 km per day (no mater if using ICE or BEV). So when you have small "100km range battery pack" you will always use 100% DoD and you need a 5000 full cycles for 500 000 km lifetime. But when you have big "500km range battery pack" you need only 1000 full cycles for that lifetime. But more important is, that bigger pack does not change your daily 100 km average, so you will be using only a 20% DoD in average and this raise your battery pack cycle life exponentially.

And this is exactly the principle which is used in Tesla batteries. I have measured Tesla 85 kWh battery cells under my standard cycle life test: (0.5C charge - 1C discharge) at 100% DoD, and they are slightly above 70% of their initial capacity after 1000 cycles = they reach standard end-of-life condition. When compared with BMW i3 prismatic Samsung 94Ah cells with more than 4000 cycles under the same test it seems that Tesla cells are crap.

But at the 50% DoD cycling, Tesla cells have still more than 85% of their initial capacity after 1000 cycles. So I believe that at 20% DoD they can do even 10 000 cycles and this gives you one milion km, which Elon Musk talked about.

So with 200 kWh or "1000km range battery pack" you will be fine even with 250 full cycles lifetime only.
 
Seems like in that scenario you are paying for a lot of battery that you will never use, and have to lug around for the vehicles' lifetime.
 
Punx0r said:
Seems like in that scenario you are paying for a lot of battery that you will never use, and have to lug around for the vehicles' lifetime.

That's different from driving any other car in what way?
 
Punx0r said:
Seems like in that scenario you are paying for a lot of battery that you will never use, and have to lug around for the vehicles' lifetime.

That is good question. Elon musk (I hate that i must so often quote him, but he is right in many questions) sees the optimum in "500 km range battery pack" = equal to 100 kWh battery in TMS/X or 80 kWh in TM3 with the capability of fast charging and a dense network of charging stations. I personally agree with him in this point and I see the 200 kWh pack for Roadster gen.2 as a marketing which says they are still "a light year ahead"
 
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