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40kwh Model S canceled
- Thread starter gobagheera
- Start date
I think people are missing one of the biggest advantages to the 40KWh buyers: Their battery pack will run pretty much forever without losing capacity. The 60-limited-to-40 pack will have three advantages over the originally planned 40KWh pack:
1) The same number of miles driven is fewer charge/discharge cycles for the cells (same KWh consumed by the car divided by a 50% higher pack capacity). Since total cycles is the most important input to the battery capacity equation, this helps a lot.
2) The cells will always be in the middle of their capacity range, which is much better for longevity than either being full or empty. (I'm guessing that Tesla will keep the cells in the middle 2/3 for this reason, rather than cutting out either the top or bottom part of the capacity; it does make balancing more challenging, but it's also not clear that balancing matters much when you're intentionally throwing away 1/3 of your capacity).
3) As the cells degrade, there's no reason to have this degradation show through to the reported range. That is, if you start letting the user have 40 KWh out of 60KWh actual capacity, after 5 years when the battery has only 50 KWh capacity, you can still let the user see 40KWh. So, no loss of range until the battery capacity is less than 2/3 of new. Given #1 and #2 above, I'd bet that it'll take more than 10 years before you see a single mile of range loss in a 40KWh car, while the 60KWh and 85KWh cars will start degrading pretty much immediately (though slowly).
Oh, and it will be pretty much impossible to brick one of these unless you really put in special effort.
1) The same number of miles driven is fewer charge/discharge cycles for the cells (same KWh consumed by the car divided by a 50% higher pack capacity). Since total cycles is the most important input to the battery capacity equation, this helps a lot.
2) The cells will always be in the middle of their capacity range, which is much better for longevity than either being full or empty. (I'm guessing that Tesla will keep the cells in the middle 2/3 for this reason, rather than cutting out either the top or bottom part of the capacity; it does make balancing more challenging, but it's also not clear that balancing matters much when you're intentionally throwing away 1/3 of your capacity).
3) As the cells degrade, there's no reason to have this degradation show through to the reported range. That is, if you start letting the user have 40 KWh out of 60KWh actual capacity, after 5 years when the battery has only 50 KWh capacity, you can still let the user see 40KWh. So, no loss of range until the battery capacity is less than 2/3 of new. Given #1 and #2 above, I'd bet that it'll take more than 10 years before you see a single mile of range loss in a 40KWh car, while the 60KWh and 85KWh cars will start degrading pretty much immediately (though slowly).
Oh, and it will be pretty much impossible to brick one of these unless you really put in special effort.
Kraken
Member
the issue with limiting the charge at the low end or the high end that no one has brought up is the fact that the battery charges way faster at the low end. Thus it would be advantages to have it be limited between 5 and 45.... this would take advantage of most of the low end while still providing some buffer for if you run out (and to ensure that you don't hurt the battery).
wraithnot
Model 3 VIN #2942 Model S VIN #5785
It all depends on exactly how Tesla implements the software range limit. I'm still of the opinion that the easiest thing on their end would simply be to change the point where the standard charge and range charge stop since you wouldn't have to change how the car deals with low battery situations or how remaining range is reported. But I bet we'll never know because I doubt Tesla will tell us. Otherwise people could game the system a bit by either counting on extra reserve at the bottom of the pack or always range charging since it won't actually harm the battery.
But no matter how they implement things, I agree this is great news for battery longevity in the 40 kWh car since the same number of miles will involve fewer full charge/discharge cycles for the cells.
Over on the Tesla forum on the "40's Need a Fix" thread @sftesla predicted this also:
http://www.teslamotors.com/it_CH/forum/forums/40s-need-fix?page=2
I responded that this "is clearly not likely to happen." Boy was I wrong.
I received the email then came here, probably the one day that I wasn't on TMC like 24/7. ha! Good news for us 40KW reservation holders. The faster performance is a bonus. I will NOT be upgrading to 60 as the 40 is fine for my wife. However, it is nice to know we have the option to pony up the extra and get the additional range of the 60.
I wonder if this means that there is no range charge on the 40. You'll always be at whatever mileage they set it at 130 miles?
I wonder if this means that there is no range charge on the 40. You'll always be at whatever mileage they set it at 130 miles?
I think this mentality that "nobody will risk their $50k car" mentality is kind of funny given the huge number of companies out there that tune and modify Porsches, BMW Ms, and AMGs (and to a lesser extent GT-Rs - ever seen an AMS Alpha 12?). These are cars that are often priced over $80k and yet the owners still have them tuned and modified to squeak out a little more performance. It wouldn't surprise me to see some of the tuner shops start developing ways to interface with the model S, especially if we find out that the cars can be modified to P85 levels of performance with (handwaving here) simple software modifications.
SuperCoug
Model S Res #7734
Yep. This is clearly a "you snooze, you lose" situation. If you had pulled the trigger on a reservation already you'd be in great shape. As a 60 kWh owner who paid the $2000 for Supercharger access because I was told explicitly it was IMPOSSIBLE to add at a later date I'm a bit miffed. I don't see how a 40 kWh reservation holder could be angry but I can see how those of us who bought the upgraded 60 could feel like the cheaper 40 would have been the better value with more flexibility at this point.
arondaniel
Il Sessanta Caricato
I for one welcome the new built-in 60kwh+supercharging upgrade path. I feel it very nicely makes up for the 18+ months of waiting and general lack of 40kwh love.
All I ever wanted in the first place was a secure upgrade path - given that increasing range/performance in this car is trivial compared to shoehorning in a big block V8. Last time I called the factory I in fact asked if I could somehow buy supercharging hardware for the 40kwh, so that in 10 years when I replaced the battery with a larger one it would be available.
Thanks Tesla! You've got a happy customer in me...
All I ever wanted in the first place was a secure upgrade path - given that increasing range/performance in this car is trivial compared to shoehorning in a big block V8. Last time I called the factory I in fact asked if I could somehow buy supercharging hardware for the 40kwh, so that in 10 years when I replaced the battery with a larger one it would be available.
Thanks Tesla! You've got a happy customer in me...
rolosrevenge
Dr. EVS
I wonder if they'll allow the 40 kWh cars to only unlock the supercharging for $2000 since that'll be on the cars as well.
No, the e-mail they sent states "If you choose to upgrade your battery, you can then also purchase the Supercharger upgrade...", so you have to first upgrade the battery.
SuperCoug
Model S Res #7734
Good point. If you get one of these 40 kWh cars with the 60 kWh battery there would be absolutely no reason not to do a "RANGE CHARGE" every day since it isn't actually a full charge for the 60 kWh battery pack. These lucky bastards who had a reservation for a 40 are getting the deal of the century! Better performance, no need to limit yourself to a standard charge, the ability to upgrade to full 60 kHw usage in the future, and the ability to activate the supercharger in the future! I'm so damn jealous I could throw up.
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Tesla did. Read the press release.
The press release says:
Note the difference in the underlined text. Until Tesla explicitly says that the 60kWh pack in the 40kWh car makes it a 60kWh car then we don't know that it has Supercharging hardware.
Subsequent to the press release, they sent an e-mail to all the 40 kWh reservation holders, and it definitely states that you can both upgrade the battery as well as supercharging capability in the future, so it definitely has the hardware included.
SuperCoug
Model S Res #7734
No it doesn't. The 40 kWh car is still going to have a range of up to 160 miles which is FAR MORE than you can get in a Nissan Leaf. Also, with the performance of a 60 kWh car the 40 kWh Model S will also be WAY FASTER than a Leaf. They are by no means "on the same level".Unless you received a time to configure email, the reservation deposit doesn't specify what pack you are reserving.
Of course it's been a long time since I made my deposit so things could be different now
SuperCoug
Model S Res #7734
Please let me know what they say. I'll probably do the same thing if given the opportunity and put that money into an extended warranty when the finally go on sale in Washington. I didn't want to hurt resale value but the construction plans for the Superchargers do not show any units being placed on I-90 in the middle of Washington which would allow a 60 kWh car to make it to Pullman or Spokane. I don't expect to be offered the ability to put my SC capability into hibernation but if offered I'd take them up on it for sure.
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