Probability of new battery tech?

[Johan]

For starters: I have reserved a Model S but now also a Model X. I'm not getting the Model S (but keeping the reservation as long as possible in order to get a test drive as soon as that's possible here where i live - Norway). The X just makes so much more sense - AWD (crucial in our long winters), more family oriented. The big draw-back of course: 1 year (at least) longer wait! That sucks.

But when thinking of the longer wait maybe there's an upside, i.e: maybe a new battery tech is introduced and the best battery may not be 85kW but rather 100+ kW??? How probable is that? I know that the Model S uses the Panasonic NCR18650 cells. I know the cells used in the Roadster were 2200 mAh (3.7 V) and we know that resulted in a 53kW battery. Now i know the Model S/X platform is larger and hence a larger battery but the big change is the new type of Panasonic NCR18650 celles used: 3100 mAh (3.6 V) and we all know this gives us an 85 kW battery. Now think of the time passed from the Roadster to the Model S. And think of the fact that the latest Panasonic NCR18650 cell is not the 3100 mAh but one that is 4000 mAh rated at 3.7 V. Tesla has not gone for this new cell in the Model S I guess since it's so new and it's not just like you pop another cell in the battery pack and then you have a new, better, pack. But it a way it's like that, isn' it?

(Those who want proof of the 4000 mAh cell can check this link: http://www.amazon.com/UltraFire-Prot.../dp/B006OHO9I2 where theyu're selling small packs with this cell, for use in flash-lights, lasers and such.

So, it's inevitable that the packs will continue to evolve, and it would seem that Tesla has a good partner in Panasonic and I wouldn't expect them to switch, since Panasonic seem to be at the forefront of battery tech. The the question is how likely is it that once the Model X (and maybe also the Model S 2.0) is produced in another 1.5-2 years time will there be 4000 mAh (or even more) in each cell? If you switch out a 3100 mAh cell with a 4000 mAh cell rated at almost the same voltage it gives an aproximate 110 kW pack (disregarding any weight difference)!

[dpeilow]

Actually the Panasonic 4Ah cell is supposed to be 3.4V. So this could be better. They need to change the name though...

[Johan]

Actually the Panasonic 4Ah cell is supposed to be 3.4V. So this could be better. They need to change the name though...

Yes, quite confusing when the just keep the same name (NCR18650) with every new version. Also, are you implying that lower voltage is better in some way? Maybe in regards to degradation/cycle life but I'm sure not when it comes to total energy storage (V*A=W)?

[dpeilow]

No, the other way around. But of course, longevity is another factor.

[Johan]

Well I've found many instances of these reported as 3.7V, another one (same product) on DealExtreme (probabaly accurate): http://www.amazon.com/UltraFire-Prot.../dp/B0067XRH8W. So I think safe to assume they're 3.7 V.

[Johan]

Well I've found many instances of these reported as 3.7V, another one (same product) on DealExtreme (probabaly accurate): http://www.amazon.com/UltraFire-Prot.../dp/B0067XRH8W. So I think safe to assume they're 3.7 V.

Though these are not Panasonic batteries and so I suppose you're right it's rumored the Panasonics will be only 3.4V. Probably they're better and safer and better life than the ones currently out there at 4Ah.

[Doug_G]

From a business standpoint, it makes sense for the S and X packs to be identical. I really doubt they will change anything unless it applies to both vehicles.

[Johan]

From a business standpoint, it makes sense for the S and X packs to be identical. I really doubt they will change anything unless it applies to both vehicles.

I agree. But it's only logical that at some point a Model S with a better battery will be sold, and if it's motsly about the cells in the pack then it should be pretty easy to just "from one day to the next" start producing cars with a new battery capacity? So how likely is it that this will occur at/before that start of production of Model X?

[stopcrazypp]

But when thinking of the longer wait maybe there's an upside, i.e: maybe a new battery tech is introduced and the best battery may not be 85kW but rather 100+ kW??? How probable is that? I know that the Model S uses the Panasonic NCR18650 cells. I know the cells used in the Roadster were 2200 mAh (3.7 V) and we know that resulted in a 53kW battery. Now i know the Model S/X platform is larger and hence a larger battery but the big change is the new type of Panasonic NCR18650 celles used: 3100 mAh (3.6 V) and we all know this gives us an 85 kW battery. Now think of the time passed from the Roadster to the Model S. And think of the fact that the latest Panasonic NCR18650 cell is not the 3100 mAh but one that is 4000 mAh rated at 3.7 V. Tesla has not gone for this new cell in the Model S I guess since it's so new and it's not just like you pop another cell in the battery pack and then you have a new, better, pack. But it a way it's like that, isn' it?

The "Panasonic NCR18650" is only 2900mah. The 3100mah version is called "NCR18650A". The 3400mah and 4000mah versions don't have an official name yet.
http://industrial.panasonic.com/www-...+ACA4001+4++WW

Production schedule is like this:
3100mah
2010 cell production start -> 2012 Model S 85kWh
3400mah
2012 cell production start -> 2014 in production vehicle at the earliest?
4000mah
2013 cell production start -> 2015 in production vehicle at the earliest?
http://www.greencarcongress.com/2009...20a77d3df9970b

Given the quotes taken at the unveil (that the Model X will use the same 60kWh and 85kWh packs as the Model S), I find it unlikely Tesla will do a cell upgrade for the Model X (or Model S in the near future). After all, they didn't do a cell upgrade for the Roadster for so many years, despite the technology having advanced very far since then. It's more cost effective to use older cells (plus there is less risk of reliability/quality issues, since they would have been in the consumer market at least for 2 years or more).

My personal prediction is the earliest point where they might use different cells is in the Bluestar (although not necessarily the high density ones, just ones suitable for the pack size). I suspect the newest high density cells will be reserved for the next gen Roadster (which will come after Bluestar according to recent reports).

(Those who want proof of the 4000 mAh cell can check this link: http://www.amazon.com/UltraFire-Prot.../dp/B006OHO9I2 where theyu're selling small packs with this cell, for use in flash-lights, lasers and such.

Those are "Ultrafire" cells, not Panasonic. Under 1A draw, those "4000mah" Ultrafire cells only measure less than 2000mah in capacity (less than half of claimed capacity). Panasonic cells on the other hand tend to measure at claimed capacity or very close:
http://laserpointerforums.com/f67/18...mah-64339.html

[doug]

Yes, quite confusing when the just keep the same name (NCR18650) with every new version.

I'm pretty sure he meant the name "UltraFire" for a Li-ion battery.