Bigger Battery?

Bigger Battery?

Someone floated a rumor that there would be a 120kWh Model X. Anyone have any info, or opinions?

GoTeslaChicago | 13 décembre 2012

Wishful thinking in my opinion, but incremental progress could make a 100 kwh battery possible by the time the Model X debuts.

Alex K | 13 décembre 2012

I think they had mentioned in the thread that the wheelbase was going to be larger and thus a 120kWh battery was a possibility. I don't know anything about a larger wheelbase. I thought it would be the same skateboard size as the Model S.

Brian H | 14 décembre 2012

Slightly extended. They've got their own stamping equipment to play with, you know!

Brian H | 14 décembre 2012

Going from 3.1 to 3.4 batteries would provide part of the boost.

Benz | 29 janvier 2013

Wow, a 120 kWh battery would really boost the range of the Model X. The maximum range then would be about 600 km (at an average speed of 90 km/hr)?

Alex K | 29 janvier 2013

@Brian H | DECEMBER 14, 2012: Going from 3.1 to 3.4 batteries would provide part of the boost.

The 3.1mAh batteries weight 45.5g each. The 3.4mAh weight 46g each. The 4.0mAh weight 56g each.

They could get extra range with the 3.4mAh battery with not much weight gain. Switching to 4.0mAh would mean more weight for more power - or they could reduce the number of cells for about the same power/weight ratio.

Brian H | 29 janvier 2013

Indeed, I meant range boost.

Yes, it's strange; the 4.0 seems to have a worse energy/kg ratio. Very odd. It would be valuable only where space was more important than mass.

danielccc | 29 janvier 2013

Going by your numbers, the 3.4 Ah cells have the best power to weight ratio, 3.5% higher than the 4.0 Ah and 8.5% higher than the 3.1 Ah.

Notice also that the 4.0Ah cell has a lower discharge voltage of 3.4 volts vs. 3.6 for the 3.4Ah battery.

The 4.0Ah a silicon base negative electrode, instead of carbon. It sounds like significantly different battery, while the 3.4Ah is more of a drop-in.

On the other hand, I see now that the datasheet for the 18650B shows slightly less capacity (3.35Ah), and weighs one more gram (47.5):

I could find no datasheet for the 4.0Ah cell, so who knows what its real specs are? I am fairly sure it's not even in production yet.

My guess is that the Model X will have the 18650B, and I would further guess that this same battery will find its way into the 2014 Model S.

The 4.0Ah cell is further out. Panasonic needs to start producing, ramp, stabilize yields, etc. Tesla would need to get some experience with it in automotive use. I don't think such a cell, even if production does start this year, will find its way into a Tesla model before 2015.

Still, even with the with the 18650B, an 85kWh pack becomes a 92kWh pack, while the 60 becomes a 65. Not bad.

Timo | 30 janvier 2013

@BrianH, those 4.0Ah batteries have silicon-based anode, and silicon is heavier than carbon. Volumetric energy density increases, but gravimetric decreases. At least for this first generation of silicon-based anode batteries.

@danielccc, I too think that this is not in production, however it has been mentioned in their webpage for about two years now, so it is a bit weird that it isn't in production yet. Maybe it has some serious flaw in it (like very poor cycle durability).

Benz | 30 janvier 2013

So, with the 18650B cells, as from 2014 we could be buying a Tesla Model X with a 92 kWh battery pack (instead of the 85 kWh battery pack), or a Tesla Model X with a 65 kWh battery pack (instead of the 60 kWh battery pack). Is that correct?

danielccc | 30 janvier 2013

@Benz: That is correct if they keep the same size skateboard. They could also make it a little bigger for the X, which would allow more batteries.

If I were them, and unfortunately (for me) I am not, I would use the same skateboard for all S platform vehicles, which includes the X, for the sake of part commonality.

BUT, this would mean the X would always have less range at highway speeds, since it has higher drag. I think it's reasonable that the S would be the higher performing model, though.

@Timo: They mentioned it in their webpage two years ago but if you read the press release it clearly states production is to start in 2013 for the 4.0Ah battery, while production did start more or less on schedule in 2012 for the 18650B.

This is logical from marketing and production perspectives. From marketing, you don't want to blowout all your improvements at once. It's better to roll out a little bit every year. From production, the 4.0Ah battery replaces carbon with silicon and I would guess that the manufacturing line needed upgrades to support that, and a careful ramp to insure quality and yield. There is a ton of work involved in doing that.

Benz | 30 janvier 2013

The success of Tesla Motors is partly based on the fact that Panasonic is constantly developing their batteries (and increasing the capacity of their batteries) as well. Every year there seems to be an improvement of 8% or 9%. I heard Elon Musk say that at the Oxford Martin School, when he was invited there to talk about the future of Energy and Transport.

That would mean that Tesla Motors could have a Model X on offer that would have a 200 kWh battery pack between the wheels in the year 2023? Offcourse there will be many other improvements by then, but let's stick to the capacity of the battery pack (in this thread).

Just imagine what the range would be on a fully charged battery?

Benz | 1 février 2013

Read this:

"Lithium technology is advancing rapidly. Old technology cells aren't good enough to make cutting edge electric cars. The lithium cells in Tesla's Model S store twice the energy (W-hr/kg) of old technology LVP-65 cells in the Boeing battery and more than the cells used in the Volt, Fisker, Coda, LEAF, or iMev. Nano-structured manganese cathodes, silicon anodes and better electrolytes will double performance compared to the Model S cells by 2016. After that sulfur cathodes, tin anodes and other new materials are in the pipeline to increase cell performance even further. Having the best cells, is one reason Tesla cars out range and out perform competitors. By choosing commodity lithium cells, Tesla gains earliest access to developed, field tested cells with the latest technology and best performance."

"Tesla's competitors have followed the 'value engineering' ethos of the car industry, choosing specialty automotive lithium cells over commodity cells. This approach may end up exposing these companies to unforeseen safety issues, and perhaps as important may leave them one-step-behind in battery technology and vehicle performance."

Tesla is on the right track heading for a bright future.

flyjeffva | 21 décembre 2013

We are 10 months since this conversation.

Does anyone have information or speculation about Tesla offering a bigger battery in the S or the X?

robert_ferrara | 4 janvier 2014

anyone hear anything new on this or still just wishful thinking?

jonerickson1 | 6 janvier 2014

I wonder if they would delay the 4.0Ah cell just for Tesla to debut it in the Model X. A 100+ kWh pack would be amazing for the Model X.

Brian H | 6 janvier 2014

A 20% increase falls a bit short of "amazing" on Tesla's scale.