Question About 4680 Cells

[Dids]

Do you have any links on the battery chemistry types that might be used in the 4680? I would have thought they would optimise one for the 4680 production line and not have to have more than one type of line.

From battery day presentation. There will be 3 types of 4680. A high iron battery that is heavier but cheaper for stationary use and for smaller battery packs like a low range city car. Second type will be similar to current chemistry for model Y. 3rd is a high nickel content battery chemistry for larger mobile packs like CT and semi... it is not entirely clear that all CT versions will get the high nickel type.

 

[JBee]

From battery day presentation. There will be 3 types of 4680. A high iron battery that is heavier but cheaper for stationary use and for smaller battery packs like a low range city car. Second type will be similar to current chemistry for model Y. 3rd is a high nickel content battery chemistry for larger mobile packs like CT and semi... it is not entirely clear that all CT versions will get the high nickel type.

Yep that is what I meant.

Was that explicitly in regards to the 4680 format, or just generally mentioned as alternatives and could be in a different format than 4680?

 

[Dids]

Yep that is what I meant.

Was that explicitly in regards to the 4680 format, or just generally mentioned as alternatives and could be in a different format than 4680?

Specific to Tesla made 4680...

 

[anionic1]

I think Ford and GM are both using pouch cells.

Those are the ones that explode just outside the warranty period right?

 

[Ogre]

Those are the ones that explode just outside the warranty period right?

That's not entirely accurate.






Some don't wait until the warrantee is over.

 

[Crissa]

You are building the foundation of your house of math on sand.

Sand is a better foundation than those assumptions.
But... https://en.wikipedia.org/wiki/Soil_liquefaction is common in sand plus groundwater.

... Now yes we could have stuck to the freeway but we wanted to take the longer scenic route. From the Poncha Springs super charger to the Santa Fe super charger has a real long stretch of 65mph signed road that we were doing 75 on and still getting passed iregularly so we would have a range loss then as well on that stretch.

Seems like you were driving really fast and should've stopped for dinner somewhere and a few kWh. Lunch at a 14-50 will get you almost 10% SoC back.

I think vendors not planning on using the 4680 pack as a structural battery will stick with the 2170 pack as they will be able to get more energy density in the overall pack.

No.
The 4680 packs in tighter than the 2170 because less wasted space to steel canisters... The bigger circumference is better at a certain pack size. Furthermore, you can get away with putting cooling above and below instead of inside the cell tessellation.



Only smaller packs and lighter vehicles will have a problem with the 4680 cells. Their tessellation will have more wasted space at a certain smaller size.

-Crissa

 

[Dids]

Sand is a better foundation than those assumptions.
But... https://en.wikipedia.org/wiki/Soil_liquefaction is common in sand plus groundwater.


Seems like you were driving really fast and should've stopped for dinner somewhere and a few kWh. Lunch at a 14-50 will get you almost 10% SoC back.


No.
The 4680 packs in tighter than the 2170 because less wasted space to steel canisters... The bigger circumference is better at a certain pack size. Furthermore, you can get away with putting cooling above and below instead of inside the cell tessellation.



Only smaller packs and lighter vehicles will have a problem with the 4680 cells. Their tessellation will have more wasted space at a certain smaller size.

-Crissa

More like sand and greywater...

 

[Ogre]

Can you explain how any of these matter in estimating battery size? If you can we can have an adult conversation about it.

You want me to explain how weight affects range and how battery chemistry affects weight?

I didn't realize we needed to return to the basics.

Put 20 pounds in a wagon. Pull it across the room. Now put 50 pounds in the same wagon and pull it across the room.

That extra pull you feel on the handle comes from the friction of the wheels rolling across the surface you are on.

The same exact thing happens with cars. If you have a 5000 pound vehicle and a 7000 pound vehicle, it takes more energy to move the 7000 pound vehicle.

Let me know if you need some more answers about friction and I can point you to some 7th grade physics lessons. Then we can talk about how battery chemistry affects battery weight. That's a little more complex though so we should make sure you understand this more fundamental stuff first.

 

[Ogre]

Their tessellation will have more wasted space at a certain smaller size.

Maybe they should consider alternative cell shapes to more efficiently pack them.

Probably shouldn't post when at this hour...

 

[Dids]

Maybe they should consider alternative cell shapes to more efficiently pack them.

Probably shouldn't post when at this hour...

Oh! It's the e Cat! Unlimited energy.

 

[Ogre]

Oh! It's the e Cat! Unlimited energy.

Maybe that's what Rossi puts in that box.

 

[rr6013]

CT3 charging cost is ½ the CT2 charging 3X

 

[rr6013]

What do you guys think about this article? Will 4680's be that quick to charge?

https://insideevs.com/news/448893/tesla-model-3-4680-charging-power-size/

The authors have gone to the effort to create one viable method and chosen metrics that can be replicated over time. That alone is the useful takeaway.

 

[rr6013]

The 4680 has a number of advantages: lower internal resistance, better heat shedding, and a new chemistry. While that should translate to faster charging, Tesla will be conservative with the tapering so that they're not replacing vast quantities of $20,000 packs under warranty.

That said, Tesla has previously pushed firmware updates that improved charging speed and/or capacity. So I would expect the 4680 charge/discharge profile to be adjusted over time as real-world data is collected.

OR stranded 4680 packs out of charge Tesla can OTA release the electrons to repiwer to closest charger. Its Tesla’s “little red gas can” solution

 

[rr6013]

I would assume the structural pack would however reduce the cost of the car structure, possibly netting an overall reduction in cost because the cells themselves would actually be used to carry load, which isn't the case with 2170 etc. where the car had to carry the battery cells instead.

BUT for the design-centric exoskeletal stainless steel body Tesla has that hand tied around its pack. SO transferring structural forces below the waist lowers center of gravity(CG) but not cost savings above the waist.

Tesla are spec constrained to 30X cold rolled exoskeletal body. Cost savings will be a function off the structural charts in volume or alloys.