When will 100+ KWh battery become available?

[Pajda]

So far there was a rule that the 18650 size cells used in Tesla batteries were already commonly available on the market in industrial grade (for laptops, power tools etc.). Even the latest industrial equivalent of Tesla 90 kWh battery cells start its mass production in early spring this year. So it should be also a good guide for guessing when and what capacity will get next Tesla battery.

My guess is 100 kWh in late 2017 still based on 18650 cells for model S and X. Only model 3 will use new (most likely 20700) size of cells at this time.

 

[Adrian]

My guess is 100kWh in 4 years. According to EM/TM, batteries improve by ~5%/year. Biggest single-step improvement will be when Tesla begins using the new form-factor batteries (18650?) probably in a year or two.

Could you elaborate on the advantages and how/why's of a different form factor? I've been very curious as to why they're using circular cells when cell phones seemingly are using rectangular batteries. How do this form factor differ and which form factor are they using now?

 

[Uncle Paul]

Believe Tesla prefers circular batteries is due to being able to liquid cool around them easier.

Cell phones will want rectangular batteries as cooling is not an issue, and they offer better packaging.

 

[Pajda]

There are two main reasons for choosing 18650 format cells for space limited apps.

1) 18650 format have the best energy density (both volumetric and gravimetric) than any other format/size over the last decade and it seems that this state will continue for next 10 years (Audi predicts that their "pouch" cells will not reach the volumetric density of 700 Wh/l before 2025).

I give you an example.

Samsung Galaxy S5 Battery specs: (prismatic format)

10,78 Wh / 45,2 g / 84x42,3x5,5 mm => 550 Wh/l and 238 Wh/l

Tesla 85kWh battery cell specs: (18650 format)

12 Wh / 48 g / d18x65 mm => 725 Wh/l and 250 Wh/l

.. new 90kWh battery uses 12,6 Wh cells with the same format so it attack 750 Wh/l.


2) 18650 (small cylindrical format) is still the cheapest format for mass production. So you get the best USD/kWh ratio on cell level (but on the other side you have problem on battery pack level - for example you must do 7104 x 3(4) precise welded spots for interfacing all cells to the battery).


By the way I think that the battery pack assembly problems is the main reason why Tesla want to use new format (most probably 20700) for "cheap" Model 3. I am quite sure that this 30% "bigger" format will not have better energy density than 18650 (otherwise laptops and other electronics will switch for it many years ago). You can check that historically the 18650 size formed the peak of highest specific energy and smaller formats like 18500 or bigger like 26650 have significantly lower specific energy density (about 30% less). So this is the reason why the new cell size will be only "a little bigger" and it will be a great success if they can stay very close to the 18650 regards to specific energy (my guess is 5-10% less than 18650). For example Samsung already released its own new format of 21700 size cells (Green Car Congress: Samsung SDI unveils e-bike Li-ion battery pack with 100km per charge) and they have only 680 Wh/l.

The point is that 30% less cell count makes a huge difference at battery pack/module assembly line when the resulting "limited" range with 20700 is not an issue for Model 3. But for Model S/X yes, and this is why i think that Tesla will stay also with the 18650 format for at least next 5 years.

 

[hill]

Along the theme of more powerful traction packs - and looking at our X configuration screen, I had a thought. With the 70kWh pack, you have air suspension as an upgrade cost. With the 90kWh pack, air suspension is included. Maybe I'm reading too much into that, but due to the additional weight for the extra 20kWh (or more? in the future?) is air suspension a necessity over the coil springs? Or perhaps, at least heavier coil springs are necessary? IOW, would/wouldn't one have to upgrade the suspension on the 70kWh Teslas' chassis if/once you add larger amounts of weight? Sure, batteries are getting lighter per kWh, but the past isn't a guarantee of how much that can or will continue. It's too early to say, perhaps, if the suspension needs upgrading. Just fuel for thought.
.

 

[beths11]

Along the theme of more powerful traction packs - and looking at our X configuration screen, I had a thought. With the 70kWh pack, you have air suspension as an upgrade cost. With the 90kWh pack, air suspension is included. Maybe I'm reading too much into that, but due to the additional weight for the extra 20kWh (or more? in the future?) is air suspension a necessity over the coil springs? Or perhaps, at least heavier coil springs are necessary? IOW, would/wouldn't one have to upgrade the suspension on the 70kWh Teslas' chassis if/once you add larger amounts of weight? Sure, batteries are getting lighter per kWh, but the past isn't a guarantee of how much that can or will continue. It's too early to say, perhaps, if the suspension needs upgrading. Just fuel for thought.
.

Well, I believe you can get the 90D with coil suspension as well? Do you think they would have a separate coil suspension systems for the 70 and the 90? Interesting. I wonder if the model S 70 with coils are the same coils as Model S 90 with coils? I believe I read about an owner upgrading a Model S 60 to a Model S 85 with a new battery pack. Suspension was never discussed.

 

[bwa]

There are two main reasons for choosing 18650 format cells for space limited apps.

1) 18650 format have the best energy density (both volumetric and gravimetric) than any other format/size over the last decade and it seems that this state will continue for next 10 years (Audi predicts that their "pouch" cells will not reach the volumetric density of 700 Wh/l before 2025).

I give you an example.

Samsung Galaxy S5 Battery specs: (prismatic format)

10,78 Wh / 45,2 g / 84x42,3x5,5 mm => 550 Wh/l and 238 Wh/l

Tesla 85kWh battery cell specs: (18650 format)

12 Wh / 48 g / d18x65 mm => 725 Wh/l and 250 Wh/l

.. new 90kWh battery uses 12,6 Wh cells with the same format so it attack 750 Wh/l.


2) 18650 (small cylindrical format) is still the cheapest format for mass production. So you get the best USD/kWh ratio on cell level (but on the other side you have problem on battery pack level - for example you must do 7104 x 3(4) precise welded spots for interfacing all cells to the battery).


By the way I think that the battery pack assembly problems is the main reason why Tesla want to use new format (most probably 20700) for "cheap" Model 3. I am quite sure that this 30% "bigger" format will not have better energy density than 18650 (otherwise laptops and other electronics will switch for it many years ago). You can check that historically the 18650 size formed the peak of highest specific energy and smaller formats like 18500 or bigger like 26650 have significantly lower specific energy density (about 30% less). So this is the reason why the new cell size will be only "a little bigger" and it will be a great success if they can stay very close to the 18650 regards to specific energy (my guess is 5-10% less than 18650). For example Samsung already released its own new format of 21700 size cells (Green Car Congress: Samsung SDI unveils e-bike Li-ion battery pack with 100km per charge) and they have only 680 Wh/l.

The point is that 30% less cell count makes a huge difference at battery pack/module assembly line when the resulting "limited" range with 20700 is not an issue for Model 3. But for Model S/X yes, and this is why i think that Tesla will stay also with the 18650 format for at least next 5 years.

Quick question:

Are the sizes of 18650 and 20700 batteries encoded in their type number? I.e., is 18, 650, 20, and 700 some type of measurements?


Next thing:

I've been thinking once Tesla starts making their own batteries, they can redesign the batteries from the ground up, chemistry, format, battery pack, etc.: they can design the actual cell internals for best cooling, integrating the cooling directly into the cells themselves, making one big battery pack that has the least extraneous parts, the most efficient use of space for purpose (i.e., as densely packed as possible for proper electrochemical, thermo, safety and structural function), etc.. Once this approach is taken, then things like the cylinder of the cell can be eliminated and replaced with a more purpose-built container that integrates the proper functions needed for a car battery. I don't know what this all entails; i.e., what redundancies can be added on purpose for better integrity or performance, what redundancies can be reduced on purpose because they actually cause more problems than they solve, etc., but even those two last concepts are not the proper way to do a from-scratch purpose-built design. In essence, I wonder, and assume, that there are huge efficiencies for building an actively thermally controlled car battery with the form factor needed by Tesla from scratch, without having to integrate off-the-shelf battery sizes and packaging (e.g., 18650, cylinder, etc.). In this case, opening a Tesla battery pack in the future won't be a situation of saying "oh, I recognize what they put in there!". It would be much more unique.

All this doesn't mean they have to sacrifice modularity, redundancy, resiliency, etc.. Far from it: those things should be designed into it. But I think it doesn't have to be in a particular off the shelf format like it is currently.

For instance: is cylindrical the best shape? Should they be able to expand in some direction (such as up), and if so, should that happen within their own packaging or outside of it? Could their packaging be oversized to handle this situation? And if so, does the packaging have to be so small that so much metal is used on tiny little 18650-sized cells? Could chemistry monitoring and balancing integration be done for every region of battery in a more fine tuned way? Can the cooling liquid be allowed to flow more closely to the chemicals? Can the electrolytic chemicals flow through the cooling system?

I don't know a single thing about the actual chemistry (I'm not a chemist).

 

[MacroP]

Quick question:

Are the sizes of 18650 and 20700 batteries encoded in their type number? I.e., is 18, 650, 20, and 700 some type of measurements?

Yes, 18650 = 18mm diameter, 65mm length, 0=cylindrical

 

[bwa]

Yes, 18650 = 18mm diameter, 65mm length, 0=cylindrical

Aha, thanks! I had absolutely no idea, until I saw someone calculate battery name by percent against another battery name, and realized what they were doing. That's the problem with metric based identification when I grew up with human-sized British measurement systems; the numbers aren't automatically recognizable as what they are if I don't know what the numbers could possibly represent in their own units.

So, a 20204 battery would be a four sided 2 centimeter by 2 centimeter cube? Not sure I get the hang of this ... but I can at least figure out the cylinder ones now!

 

[MacroP]

So, a 20204 battery would be a four sided 2 centimeter by 2 centimeter cube? Not sure I get the hang of this ... but I can at least figure out the cylinder ones now!

Someone told me ages ago that the last digit (zero) meant it was a cylinder so I've been telling people that ever since. Now I'm unsure if it's true or just merely a coincidence because the character '0' looks round.

Now that I think about it - I've ordered much larger LIFEPO4 lithium cells in the past and these were 32113 size - so 32mm by 113mm. My zero = cylinder plan has failed. I think the last digit in a 18650 cell is merely a place holder for cells 100m or longer.

 

[goneskiian]

Quick question:

Are the sizes of 18650 and 20700 batteries encoded in their type number? I.e., is 18, 650, 20, and 700 some type of measurements?


Next thing:

I've been thinking once Tesla starts making their own batteries, they can redesign the batteries from the ground up, chemistry, format, battery pack, etc.: they can design the actual cell internals for best cooling, integrating the cooling directly into the cells themselves, making one big battery pack that has the least extraneous parts, the most efficient use of space for purpose (i.e., as densely packed as possible for proper electrochemical, thermo, safety and structural function), etc.. Once this approach is taken, then things like the cylinder of the cell can be eliminated and replaced with a more purpose-built container that integrates the proper functions needed for a car battery. I don't know what this all entails; i.e., what redundancies can be added on purpose for better integrity or performance, what redundancies can be reduced on purpose because they actually cause more problems than they solve, etc., but even those two last concepts are not the proper way to do a from-scratch purpose-built design. In essence, I wonder, and assume, that there are huge efficiencies for building an actively thermally controlled car battery with the form factor needed by Tesla from scratch, without having to integrate off-the-shelf battery sizes and packaging (e.g., 18650, cylinder, etc.). In this case, opening a Tesla battery pack in the future won't be a situation of saying "oh, I recognize what they put in there!". It would be much more unique.

All this doesn't mean they have to sacrifice modularity, redundancy, resiliency, etc.. Far from it: those things should be designed into it. But I think it doesn't have to be in a particular off the shelf format like it is currently.

For instance: is cylindrical the best shape? Should they be able to expand in some direction (such as up), and if so, should that happen within their own packaging or outside of it? Could their packaging be oversized to handle this situation? And if so, does the packaging have to be so small that so much metal is used on tiny little 18650-sized cells? Could chemistry monitoring and balancing integration be done for every region of battery in a more fine tuned way? Can the cooling liquid be allowed to flow more closely to the chemicals? Can the electrolytic chemicals flow through the cooling system?

I don't know a single thing about the actual chemistry (I'm not a chemist).

There's a WHOLE area of this forum dedicated to this type of in depth battery tech discussion...

Battery Discussion

But to add my thoughts, the cylindrical shape of the cells allows them to pack the cooling all around each one taking up what wasted space would be there if they were all just crammed together. Somehow I don't think the cooling chemicals would play nice with the actual energy storage ones, but as you might guess, I'm not a chemist either (but I have stayed at a Holiday Inn a few times! Haha! ;-) ).

I believe JB has stated that the cell form factor is pretty ideal but a slightly larger one (hence the references to 20700 cells you've seen) would allow for more energy density (there's a video out there of him talking about this somewhere).

Also, I believe that Tesla already designs their own chemistry as well as how the cells are constructed. It's the size that's dictated by the actual manufacturers due to manufacturing equipement constraints.

 

[MrBoylan]

Well, I believe you can get the 90D with coil suspension as well?

Nope. Air Suspension is required (they say "included") for the 90D. No way to deselect it.

 

[beths11]

Nope. Air Suspension is required (they say "included") for the 90D. No way to deselect it.

I just went to the design page for a Model S. I select 85D as a base and added the range option($3,000 90D). Smart air suspension was not added. Looking at the order page, smart air suspension is a separate $2,500 option. I was able to set up an order with no air suspension. I hit next and got the TESLA ORDER PAGE.What am I missing?

 

[goneskiian]

I just went to the design page for a Model S. I select 85D as a base and added the range option($3,000 90D). Smart air suspension was not added. Looking at the order page, smart air suspension is a separate $2,500 option. I was able to set up an order with no air suspension. I hit next and got the TESLA ORDER PAGE.What am I missing?

Are we talking about the Model S or the Model X? At this time the X90D comes with the smart air suspension. You cannot unselect it.

 

[beths11]

Thank you goneskiian, I was talking about the Model S. I understand at this time Tesla is bundling many options to increase profit from users anxious to get the Model X. I guess only time will tell if air suspension is truly required on the X and it gets un-bundled at some point. It would also lend to simpler production without a coil option. Whether it is required for the battery pack, remains unanswered in my mind.

 

[MrBoylan]

I just went to the design page for a Model S. I select 85D as a base and added the range option($3,000 90D). Smart air suspension was not added. Looking at the order page, smart air suspension is a separate $2,500 option. I was able to set up an order with no air suspension. I hit next and got the TESLA ORDER PAGE.What am I missing?

You're missing that we are discussing the Model X, not the S. And by "we," I mean "me."

After all, this is the Model X Battery and Charging forum, and the question asked was about the X getting a larger battery, so who can blame me?

Smart Air Suspension is required/included on the Model X 90D or P90D; no way to deselect it. It's also required on the Model X 70D if you select the towing package.

It may be that the Smart Air is required for the Model X 90D due to the extra weight, or for the efficiency gains at higher speed, or just because Tesla wants to maintain a more "premium" level of performance and feel on the top-end model. Or it may be that they feel like making more money on the 90D and will eventually offer coil springs for the 90D as well. Who knows? It's hard to read Elon's mind. When I try, I keep seeing a big red circle. So either he is a fan of the Japanese flag, he has a thing for the planet Mars, or he's imagining Clifford the big red dog, curled up by the fire. I'm going with Clifford.

 

[joefee]

100kWh with the Model 3 launch. Upgrade of course ..... along with the Roadster Super Ludicrous Performance option (0-60 in 1.6 sec)

 

[MrBoylan]

100kWh with the Model 3 launch. Upgrade of course ..... along with the Roadster Super Ludicrous Performance option (0-60 in 1.6 sec)

I think you mean Maximum Plaid.

Spaceballs - Theyve gone into plaid - YouTube

 

[spaceballs]

I think you mean Maximum Plaid.

Spaceballs - Theyve gone into plaid - YouTube

I agree

 

[bwa]

With respect to 100kWh batteries and above for Tesla cars, am I correct in guessing that Tesla would want to only increase capacity at no weight gain, and if possible, try to increase capacity with a slight weight loss? So, if they could, for instance, increase capacity to 100kWh without weight loss, they would increase it to 95kWh instead so they can both get distance gain AND weight loss? Perhaps if 100kWh was same weight, they could make 95kWh the new "standard" and 100kWh would be a slight optional "upgrade", getting the best of both worlds: less weight, longer distance, and another premium upgrade profit center.

What this would mean in terms of timing is that we would have to wait for the batteries and/or pack design to come in denser energy and/or lighter design. It's been written here that while they are slowly making progress on that, it's not like Moore's law speed, so it will take a while.

Tesla is highly focused on Model X, Model 3, Gigafactory, Tesla Energy (PowerWall, PowerPack), SuperCharger network, new car factories, and a whole bunch of other stuff (Space X, Solar City going expansion nuts with its own gigafactory, acquisitions, market expansion), so while I'd like to wish Tesla has their own separate battery and battery pack development facilities that do their development in parallel with everything else going on, I wouldn't be surprised if they don't come out with the next iteration for longer than excited people would want to wait. Even if Tesla is doing top-notch battery research for this very purpose, it's entirely possible it's being used entirely in the Gigafactory factory line, so we won't even see the improvements until that factory starts shipping.

Another thing that could cause delay in new capacities is that they could successfully redesign the entire battery pack for superior performance (superior storage, lower weight, higher throughput, longer lasting, faster charging, better conditioning, more efficient, etc., any combination of those), and that redesign requires a redesign of the vehicles they're installed in such that they're not (immediately) backward-compatible to old vehicles. Tesla is committed to backward-compatible improvements, but those might take longer than initial improvements in capacity that are only installed in, say, Model 3, Model X version 2, Model S version 2, etc.

I heard the 90kWh battery pack is an experimental pack, along with the 70kWh model. When will that experiment end? There's even a slight slight chance that experiment WILL end and all the packs would revert to 70kWh (but heavier more expensive price point) and the old 85kWh, for "product stability" reasons (i.e., a successful conclusion of the experiment that has the conclusion "it's not a good idea for that chemistry").

All I'm trying to say is if anybody is waiting anxiously for 100kWh, that they ought to temper their enthusiasm for such a pack by a good dose of time.