I still occasionally hear about people having battery pack failures. With a structural pack, would a battery pack failure mean they'd have to throw the whole car away?
When Tesla first put out the Roadster and then designed the S, they arranged the batteries in modules so parts of the pack could be replaced if they failed ... because failures happened. Even before the structural battery Musk has said that they are doing away with modules because they just don't fail, making their extra weight and complexity a negative. Of course there can always be exceptions to 'they just don't fail'.
I believe Sandy Munro initially suggested the new 🔋pack would not be replaceable & he thought it was okay due to very long life; however, I was concerned as robotaxis these vehicles will see a LOT more runtime. If 🔋pack can still be replaced after 1 or 2 million miles, then FSD value goes up. Software license becomes most valuable automotive part affording all other parts to be replaced (car will never be "totaled" in an accident).
Check out the Gruber Motor Company videos. Their experience with Tesla batteries, is that you just have a few cells going bad at a time, after a nice, long time. If the diagnostic information is available, the bad cells could be drilled out of a structural battery, and even be replaced. th-cam.com/video/F-B_8oMZNeI/w-d-xo.html Eventually, there will be enough cascade failures, that the battery will be a write-off.
Anyone else find it amazing that we are now on PART FIFTEEN of the videos explaining battery day? I'm not sure if that shows just how much Elon wants to innovate or how incredibly deep your videos are able to explain the finer details. I'm sure is a combination of both. Kudos to both of you!
Yes, good move! I’ve been supporting for sometime and happy with my decision. He is head and shoulders ahead of any results I could deliver, so supporting Jordan is an easy way to hit the research target. I get great results at very low cost and effort!
Engineer here. That's why I commented on your latest video that I can hardly wait this one! Shear force explanation: it was very well done, I don't think an in depth explanation would be needed for this video. Another note: structural battery pack and front/rear castings integration will happen with bolts. I base my conjecture on these: the casings are made of aluminium, and the battery pack housing seems to be steel, those two are very hard to weld together. Second: if servicability(?) is important any damage to these parts will result in throwing away the whole car! Bolts makes a much more reasonable choice here.
I agree on the bolts, but based on the renderings Tesla showed of the battery pack, as well as the need for the pan to be as thermally conductive as possible (as the cell tops and bottoms are bonded onto it), it might be cast Al. Not necessarily HPDC, just a typical mold casting. Or maybe a cast Al piece with cooling channels inserted in a welded sheet steel pan. But both the battery pack and the front and rear castings will have to be structurally secured against the ultra-hard steel roof arch elements and the A, B and C beams.
@@tavi_chocochip We don't know the cell tops and bottoms are "bonded". Two plates with moulded faces to lock the cells and vertical bolts between the plates to put the cells in compression would be very strong, especially if the cell casings where glued to each other.
If I understand correctly the new charging curve will be improved by: 1. More Silicon 2. Tabless (less resistance/heat) 3. The better cooling system from the new pack design
Plus 4680 tabless resistance (or lack of) preventing hear build up? I still maintain figures quoted only benefit from the mechanical changes rather than any chemistry/ materials.
Yup! Tesla basically confirmed faster charging rate by stating that energy volume of a cell is up 5x but the power output is up 6x. It reasons to stand that your 3 points allow for faster charge and discharge.
@@Klemeq No. "Because of the 5x" They stated more charge *capacity* per cell, not faster charge *rate* per cell. There's 5x the material in each cell, so it will hold 5x the energy. Now, IF the resistance of the cell is lower, (tabless) it will accept more current without heating. THAT will allow faster charge, but it's nothing to do with the capacity. That works in reverse for power (discharge). Note they said "5 times the energy (capacity) 6 times the power" That implies that the power capacity of the cell (5 times the size) has increased to 6 times the old 2170 cell. So the percentage increase is 6÷5 = 1.2 = 20% improvement That improvement would apply to the *pack* A pack which wastes 20% less from heat (resistance) will be 20% more efficient. I think that's where the "16% range increase" comes from(?)
Also interesting are the implications for electric flight. Developing the technology and fine-tuning manufacturing to make batteries structural could really reduce weight for flight applications (similar to the wing-as-fuel-tank design of modern planes mentioned during Battery Day).
I agree with your assessment that coolant will go under the cells... Not only does it lower the CG, but the coolant channels could be designed to provide a crush structure to protect against underbody levering or spearing impacts.
Other manufacturers claim they have "structural battery packs", but that just means they have beefy battery cases and transmit some load through them. Tesla is actually using the individual cells themselves as structure and is transferring 100% of the load through the battery.
At 5:14 I think the best way to understand is that the cylindrical (almost honeycomb) battery are used as a column to support compressive stress between the compressed upper panels and the tensioned below panel. It's just like a I beam but in every direction so it give also torsional strength
Fascinating as always. I always wondered what sort of cascade we'll see as weight comes down. Lighter pack means we need fewer batteries to get the same range, but that could also mean lighter wheels, tires, brakes, and other components. Reduce that weight, now we need an even smaller battery, which reduces weight again.
The concept of negative mass is a counter intuitive concept. It should thought of either battery being in structural debt or having a structural credit. This means the battery either requires structural mass or supplies structural mass. The interesting part is that, if you can make structural part out of batteries then you can carry a larger net load.
coppers thermal conductivity is only better if both electrodes have the same thickness. Al weighs a quarter and has half the conductivity, so if you make the Al Electrode 4times as thick it will weigh the same but have double the thermal conductivity. That is what they did in the end :)
Another excellent analysis. I'm an aerospace/mechanical engineer, and I think your explanation of the advantages of the cells bonded to the face sheet is dead on. This set up is essentially the same as the composite sandwich structures that we use in aricraft and spacecraft to keep the mass low. A typical sandwich construction would use carbon fiber composites with aluminum honeycomb core. The aluminum walls are very thin (a little thicker than aluminum foil), yet they're excellent at tying the load paths of the face sheets together. Great stiffness for the weight.
Your description is very good. The key point that you make is in conveying that the battery shell is in intimate contact with the battery immediately adjacent to the next battery. The same concept is explained when you compare the breaking of a single straw versus the force required to break dozens of straws while each straw is in intimate contact with the next straw. However, in a micro analysis sense, all failures described as 'shear' failures are really failures in compression/tension. However, we use the word 'shear' failure as a generic expression of failure modality.
Jordan, this is EXACTLY what I was referring to for more mech eng focused videos. I should have sent it to you, but I put together a CAD FEA simulation of a traditional battery vs the 42 x 23 electrek leak. Found that the structural pack was around 2.3 times as rigid as traditional pack under same loads. LMK if you want to see it. By the way, you did a great job explaining the shear transfer and polar moment of inertia benefits. Are those your Blender models?? Look excellent!
😁 Yeah, I did the blender on this still image. Damn! Good information... I'm actually already done scripting and recording the video after this one. If I can find a place to squeeze in more information, I'll let you know! I still have to go in an do some surgical edits after getting feedback on today's video.
Your videos are the best, and I find that when I see one in my Notifications, I usually pause my TH-cam queue and watch the new TLF instead. One small note: I found the milk jug example a tad cumbersome. People intuitively understand polar moment of inertia almost without explanation, no matter how daunting the phrase "polar moment of inertia" may at first seem. The image that I have seen others use to create that Eureka moment in the learner's mind, is to mention the phenomenon where a figure skater who is in a spin speeds up when she pulls her arms in close to her body. .
Structural Pack: twisting a sheet is like bending in 2 dimensions at the same time, and with the honeycomb in it, its act like a very thick sheet (like the honeycomb paper filling from IKEA ;)) So in one direction (bending) it works like an I-beam or H-beam. As explained in the Video, the upper and lower flange is connected with the web. The web take the shear forces and the flanges most of the bending forces. While bending, the outer flenge get streched, the inner one compressed. To torsion this I-beams are weak. With a honeycomb web, you get stifness in all directions, over the whole area, because the "webs and flanges are everywhere in all directions. But I think you've portrayed that well enough already. After all, it's about the benefit of it all and how it works out.
Great video, as an Engineer I agree with the vast majority of your points. A couple of other forces for instance and effects on rigidity and driving behavior come into play too but nothing that conflicts with the overall message of your video. The new design of the 4680 and the new structural design in the vehicle allows further improvements on the castings that have another positive impact on weight as well. In addition this new design opens the door for further improvements Tesla won't start with at version one but for future iterations.
Hello, thanks for the explanation. I realize the numbers are based on the presentation, but they seems very optimistic. Lets say we have the 300Wh/kg new cells. Cell weight with the old cells is 330kg. Now in a typical pack we add 50 percent as you mentioned. That would be 330kg into the almost 500kg on the pack level. Meaning the extra stuff (epoxy, cooling wiring etc) weight is 170kg. With the new 4680 cells we can expect all the extra stuff be much lighter but still, even if it had half the weight, so 85kg, this means to get to the "effective" weight of 300kg on the pack level we have to save 85kg+30kg=115kg of the structural weight. Since the entire aluminum body of a model S is supposed to be about 200kg that seems way too much.
Wow this video in particular really answered a lot of things that I was wondering about. The details about the Rockers becoming redundant in particular has bugged me since battery day.
Recycle of used cells? Page 11:00 It is advisable to consider (aluminum extruded) honey comb structure in separate from the use of cell wall as integral part of the comb. Same way we drop in a cell in our flash light.
I just made a similar point. 5:56 A "drop in" cell (better still, press fit?) Instant grounding of the case (one less connection) Recycling just needs the cells fully discharged then either dropped, or pressed out on a jig.
Thank you so much Limiting Factor! I'm actually watching your videos to understand more about the battery since I've been offered a position in battery manufacturing for Tesla! Your videos is helpful (even if you are not an expert)
Furniture makers use 2 sheets of veneer that sandwich something called honeycomb. This honeycomb is cardboard, about an inch thick. It is glued to the veneers and there is a solid wood edge along the sides of the panel. This panel can be used for table tops, conference table tops or other structural parts of furniture. It is very strong and light compared to other construction techniques. Also, there are companies who use thin sheets of metal which sandwich styrofoam, to form structural wall panels in prefab homes. It's the same idea, with a light core and thin structural sheets on the faces of the panel. The torsional strength is amazing when considering how much material would need to be used to separate if there is a separate frame and non-structural battery pack. Of course, the batteries as a core are not as light as styrofoam or this cardboard honeycomb but the weight savings of using the pack as a structural piece is significant. What will Tesla think of next, to incorporate structure with some other function? I heard the Tesla cars have air shocks for suspension and that the air tank for it has been incorporated into also serving as a structural cross member in the front of the car. A tube shape has a lot of structural support for both a cross member of the frame and for an air tank and, because the air is amorphous and does not need to be a specific shape, the tank can be long, like for a cross member rib for the frame. Is there anything else that can double as structure and some other function? Or can one part serve 2 functions other than structure? Or can one part serve as structure plus 2 other uses? And applications: we can ask, are these techniques the future of all cars? Would the bed of a pickup truck serve as a place for a structural battery pack? What about the floor and walls of a trailer for a tractor trailer (the semi)? And can the roof of a trailer have solar panels? If not for a tractor trailer, maybe for a straight truck? And what if Tesla created some sort of version of blade batteries, built for structural battery packs? Would that save more space than the cylindrical battery? (Place the blade batteries on their sides instead of like a deck of long cards, the way BYD does, so the thickness of the pack is an inch or less.)
Thanks for the video Jordan! It was very insightful. My dad and I were just discussing how exactly they would go about cooling packs and your explanation seems the most plausible. Your videos always have good research/sources and your explanations are very helpful.
My personal thinking is that cooling could be (and perhaps will be) done on both top plate and bottom plate.....to ensure more uniform heating/cooling (and thus ensuring uniform aging) through the entire cell.
Jordan, That honeycomb structure at 5:56 has caught my attention (repeatedly) I wonder what it's made from? Megapress casting?? Insulator? Or metal? (Would be an interesting way to aid *fast* construction? "drop" the cells in, no glue!). If metal, instant "common grounding" for the cell cases? Would that mean only *one* conventional connection needed per cell? One circuit board, dropped on top, fusing and terminal tabs on the board, press fit onto the cells, no welding!? Recycling? If those holes allowed a press fit of the cell casings, just needs a jig and a press to remove the cells after discharge.
Not sure! It looks like some kind of injection molding? I have little understanding of manufacturing techniques. So much to learn! Oh yeah...I agree on 'dropping it in'...covered in the next video. 😁
Another great video. Could you please somehow number the 15 videos in the series? I think I have watched them all but I’m unsure. The first one you suffixed with #1 but non of the others. Keep up the great work in educating us.
I had that issue before, so it's likely a common issue for us viewers... meaning, would probably benefit new viewers that are gonna stumble onto your channel as well. You can expect many, many more will do that & be thrilled to stay for this awesome education you provide
Excellent explanation of the planned structual battery. I have 4 concerns for it: 1. Crash security? 2. Is repair possible, to exchange spoiled cells? 3. Is use as scond liefe (use of old batterys as stationary battery) possible? 3. Is recycling possible (here you told us your opinion in the video)? Would be great, if you or someone could check the first 3 points!
A much more robust and simple wiring scheme would be to alternate the orientation of the cells positive up and down. Simple straight connections without the precision required for attaching to the edge of the cells on the same end as the center connection. Thermally conductive but electrically isolating epoxy could mean agnostic orientation. It seems unlikely that the thermal conductivity difference between Al and Cu is meaningful in the short distance between the end of the folded conductor and the top of the cell can. Tesla does have the precedent of the more complicated wire harness but the structural pack offers this option and I hope they take advantage of it.
Page 9:15 : Yes, excellent thermal transfer - from the core to the bottom by copper leads - only to fall short passing it to inner cell wall ie negative terminal casing. Why? It count on point contacts by a force derived from annealed (soft) copper leads, a problematic electrical connection method that responsible engineers will avoid, so how good is thermal dissipation? Nearly as good as conventional single welded tab? That defeated Tesla’s claimed thermal advantage.
-Great stuff as usual Jordan. -I don't know if you ever delve into Tesla charging infrastructure, but I'd love your opinion (a video would be be great of course) on the large Supercharger installations in the works (several biggies along Route 5 between LA and San Fran) and whether they may actually be, at least partially, Megachargers for Semi. -For example check out Harris Ranch. It appears to be a truck stop already, lots of space, permit for 80 Superchargers. -Also what is the feasibility of Semi using several (four, six, eight) Superchargers to charge in the wee hours when nobody there? Or a setup like the mobile Megapack that was deployed in 2019 at the Supercharger in San Luis Obispo. -I can give more deets on this stuff if you're interested.
Megacharger. I've mentioned my hypothesis before. We've seen a Semi charging at a pair of "conventional" superchargers with the cables connected to a common plug, which was plugged into the vehicle. If we assume "Megacharger" denotes 1000kW(?), Tesla already has V3 units capable of 250 kW, (currently limited by the car batteries). Imagine a drive through charge bay with a pair of V3 units on either side, paired to one plug per side. (Similar to a diesel Semi with dual tanks?) That gives Megacharger performance with proven, modular technology. As you say, there's no reason a Semi can't "trickle charge" on a single V3 overnight (or one per side).
@@rogerstarkey5390 Love it. It seems like a no-brainer for Tesla to leverage the Supercharger network in some way to enable Semi to go long distance, at least at first. (but I'm a biased reservation holder, heh..) Not feasible at all locations due to space/accessibility, but I think it would work at some, especially given the small number of Semis in the beginning. I've heard the goal is for Megacharger to charge at 1.5MW plus. Full charge in... 45 min? Question: Is it possible to achieve a similar result by somehow connecting six v3 Superchargers to Semi? Question: Is it feasible (financially, technically) for Tesla to place a Megapack at Supercharger stations, "trickle charge" it at night, use it to Megacharge Semi?
Running change to cell count? Is possible only separation between one cell to the next remains evenly distributed to avoid differential strong vs weak spot leading to structural torsion weakness or tinkles on flat surfaces.
As long as the pack fits in, the shredder doesn't care if it's structural or not. I don't think large-scale recyclers are going to pry out individual cells.
My 2 cents is that the first 4680 cells will not be used as a cell to chassis as presented during the battery day. The reason is that they will be used on model Y Berlin that will still have a pack as seen from picture at 5.56. the full cell to chassis is probably going to be used on model S plaid+, cybertruck and roadster, with a cooling plate (for cybertruck and roadster only) on the bottom rather than serpentines cooling channels (needed on Y as the pack height is not indefinitely extendable on a vehicle designed for 2170s).
And again a brilliant and easy to understand (for once😈) video from Jordan ! I would love to see an interview / collaboration of yourself and Sandy Munro... Keep well, both of you 👍🍻🍺
On the "negative mass", not sure how the number for *cells weight* is sourced, but just a possibly obvious / dumb comment: the sum weight of the 4680 cell cans should be smaller than that of the 2170s, even if the active material weights are similar in the two (energy-equivalent) packs. So the total weight of cells in the 4680 pack would be smaller than the cells in the current LR packs.
@@w0ttheh3ll Every part of the battery can theoretically provide structural support, even the powders within them can transfer forces applied to the cell.
I would question if reducing a lot of what they consider redundant structure around the current battery pack and making the pack a structural member would tend to reduce crashworthiness and increase the risk of battery pack damage and higher possibility of fire in more severe accidents.
And this is what I said when someone wrote an article at Cleantechnica saying that the Roadster 2.0 wouldn't have better handling because batteries are heavy and all that jazz. Heck! That roadster was made with Model 3 batteries! 4680 cells, cell to structural pack, Cybertruck's 30X Stainles Steel, huge single casting pieces, etc all those innovations didn't exist back in 2017! All those could be added to both the new Roadster for better handling and to the Semi for longer range! And to think even more energy density is being developed (I think I recall Elon mentioning between 400Wh/Kg to 500Wh/Kg to achieve a possible electric plane jet with VTOL capabilities)
I've noticed that the jelly-roll doesn't go to the absolute center of the cylinder. Could the cylindrical space in the center of the 4680 contain something to further facilitate cooling?
Possibly, there were rumors before battery day that there is an aluminum core in the center of each cell. But, I've heard a lot of rumours. I only share information that has corroboration in some form or another.
As Frank Spencer of 'Some Mothers Do Av Em' fame would say:- 'Also...' Because the 4680 battery has a larger cell zize it's surface area to volume ratio is less than in smaller cells. Since the casing of the cell is made of metal this will likely contribute to a weight saving, though I note that the sheet metal thickness used for the 4680 case seems to be rather thicker than I would have expected to be necessary.
@@thelimitingfactor Monthly/ 3-monthly (quarterly) is more doable & relavant... Maybe even once half a year, so that there is enough big news, to have enough relevant material to cover
@@thelimitingfactor You know, only if you ever feel you wish to have more work :D Once you expand on how many people create content for this channel, it could work... I see your channel grow A LOT in the coming years.
All the more reason why they can go all in on LFP. I am not sure why on battery day they seemed to indicate that LFP is only for the model 3 and the 25K car?
It's a volume calculation (as it's always been) Length between the axles, width of the vehicle, weight of the vehicle, performance required. Every pack density/ volume will have a "sweet spot" for vehicle performance.
@@red-baitingswine8816 But the material is much more expensive and in short supply. The high performance cells will be used where weight/ volume reduction is more important that cost.
I worked it out at one point and I would need to recalculate it. Ultimately it doesn't matter anymore and I didn't keep the calculation because the capacity of the individual cells won't be what drives decision making. It will be cost, trim level, and material availability.
I worked out the roll length of a 4680 compared to a 2170 cell. (Very useful "carpet roll" calculator on line😁) Assuming the material thickness is the same, when the increased length is multiplied by the respective cell height, the *surface area* of the roll in the 4680 was almost exactly *5 times* that of the 2170. (Strange that?) This leads me to the conclusion that the "5x energy capacity" statement on Battery day took no account of improvements in chemistry and was in fact just down to more "stuff" inside each can. (The "6x power" was down to that increase, plus cell resistance/ tabless design)....? If that's the case, imagine what happens when chemistry/ materials increase the energy density of that roll material by 20-30 % !!! 600 cells for a model 3 pack? A *HUGE* weight reduction for the Semi(!)
I'd like to see some comment on the potential problems that Tesla is having scaling up and producing the 4680. I have heard things about heat problems, questions around robustness and the yield of the manufacturing process. Any thoughts? Thanks for the great videos by the way, added to my list of 'must watch'
An exercise for the next super market visit! 6 pack of beer (mmmmm beer) The tops of the cans are held by plastic. If you pull one can sideways, they all move. Put one at the bottom, it moves in its own. Now imagine that plastic on the bottom as well. Much more rigid, but.... If you push one lower corner, then push the opposite *upper* corner, the cans tilt and slide against each other, knocking the "cube" out of square (stops then "falling over") Now apply glue to the cans, sticking them together.... Zero movement. That's where the torsional/ shear strength is coming from. That's then bonded to the plates, and all forces are transferred across the plate rather than trying to bend it. Pinch the two plates together at the sides, extremely strong. It's also the cylindrical shape of the "can". Cubes wouldn't be as strong (A structural engineer may disagree?) Imo, I don't think the material inside the can will be stressed (under pressure) at all in this case.
is a battery cell more, or less dense than water? Place the cooling liquids lower might mean the cells are higher. If cells are more dense than water, CG would rise.
Would the batteries need to be bonded to the top and bottom plate for it to be structural? If you bonded the batteries to each other, effectively you make a battery brick. Then, if you placed the brick inside of a box, wouldn't it then provide structural rigidity to the box?
Both. Glue them together, that gives torsional stiffness to the *pack* (cell block), then glue the plates to mount the block to the car. All (most) of the force on the plates would be lateral apart from the actual edge fixings.
I've always wondered about the epoxy, or what have you, on the old pack. Surely there's some chemical that easily dissolves it and makes it much easier to recycle.
Cooling on top seems reasonable as it insulates batteries from passenger comparment, Dont want to cool the outside world. Dont want high temps getting to passenger compartment. I think heat rises in solids too.
Recycling. On the existing vehicles the battery packs can be removed from the vehicle and sent for recycling. With the structural batteries this probably means the vehicle will need to be sent back for recycling. This To my mind is good, it means that the front and rear castings can be salvaged at the same time. Ok the alloy could change from time to time but tesla will know what is in every casting it recovers. I think we will see all Tesla factories having a recycling facility soon to make the most of the existing materials. Humn the above also goes for the glass and probably many other elements. Is this perhaps the way all recycling should be?
I was under the impression that the fragility of the cell wiring was making it an overcurrent fuse. If one cell overcharges the fusible link would isolate that cell from the system.
Seems like Tesla will start in Texas and Berlin with regular 21700 packs, to soon upgrade Berlin to work with the 4680 structural battery pack once they solved the 4680 quality
Mr Musk is unrivaled, he has a lightning-fast mind like his products and the competition knows it too it would be nice if he designed a car with a panoramic floor as the roof unique and futuristic project the fox
I still occasionally hear about people having battery pack failures. With a structural pack, would a battery pack failure mean they'd have to throw the whole car away?
From what I can see, no. You are just changing how the cells are bonded within the pack, not how the pack is bonded to the vehicle.
When Tesla first put out the Roadster and then designed the S, they arranged the batteries in modules so parts of the pack could be replaced if they failed ... because failures happened. Even before the structural battery Musk has said that they are doing away with modules because they just don't fail, making their extra weight and complexity a negative.
Of course there can always be exceptions to 'they just don't fail'.
I believe Sandy Munro initially suggested the new 🔋pack would not be replaceable & he thought it was okay due to very long life; however, I was concerned as robotaxis these vehicles will see a LOT more runtime. If 🔋pack can still be replaced after 1 or 2 million miles, then FSD value goes up. Software license becomes most valuable automotive part affording all other parts to be replaced (car will never be "totaled" in an accident).
Check out the Gruber Motor Company videos. Their experience with Tesla batteries, is that you just have a few cells going bad at a time, after a nice, long time. If the diagnostic information is available, the bad cells could be drilled out of a structural battery, and even be replaced. th-cam.com/video/F-B_8oMZNeI/w-d-xo.html Eventually, there will be enough cascade failures, that the battery will be a write-off.
The front radiator support is structural, but also removable. Structural doesnt (perse) mean it cant be disasembled.
Anyone else find it amazing that we are now on PART FIFTEEN of the videos explaining battery day? I'm not sure if that shows just how much Elon wants to innovate or how incredibly deep your videos are able to explain the finer details. I'm sure is a combination of both. Kudos to both of you!
Indeed! We're 7 months post Battery Day and we're still deep diving a single presentation with more yet to come!!!
Okay, you win. I want to ensure you can keep doing this so I'm supporting you on Patreon and voting with my wallet.
Lol! Thanks Chris 😀
Yes, good move! I’ve been supporting for sometime and happy with my decision. He is head and shoulders ahead of any results I could deliver, so supporting Jordan is an easy way to hit the research target. I get great results at very low cost and effort!
Engineer here. That's why I commented on your latest video that I can hardly wait this one! Shear force explanation: it was very well done, I don't think an in depth explanation would be needed for this video. Another note: structural battery pack and front/rear castings integration will happen with bolts. I base my conjecture on these: the casings are made of aluminium, and the battery pack housing seems to be steel, those two are very hard to weld together. Second: if servicability(?) is important any damage to these parts will result in throwing away the whole car! Bolts makes a much more reasonable choice here.
I agree! Noted in the next video
I agree on the bolts, but based on the renderings Tesla showed of the battery pack, as well as the need for the pan to be as thermally conductive as possible (as the cell tops and bottoms are bonded onto it), it might be cast Al. Not necessarily HPDC, just a typical mold casting. Or maybe a cast Al piece with cooling channels inserted in a welded sheet steel pan. But both the battery pack and the front and rear castings will have to be structurally secured against the ultra-hard steel roof arch elements and the A, B and C beams.
@@tavi_chocochip
We don't know the cell tops and bottoms are "bonded".
Two plates with moulded faces to lock the cells and vertical bolts between the plates to put the cells in compression would be very strong, especially if the cell casings where glued to each other.
I don't understand how the cells are bonded with the sheets over and under. In my head, if they are not bonded, the cells will simply move around..
If I understand correctly the new charging curve will be improved by:
1. More Silicon
2. Tabless (less resistance/heat)
3. The better cooling system from the new pack design
Bingo!
Plus 4680 tabless resistance (or lack of) preventing hear build up?
I still maintain figures quoted only benefit from the mechanical changes rather than any chemistry/ materials.
Yup! Tesla basically confirmed faster charging rate by stating that energy volume of a cell is up 5x but the power output is up 6x. It reasons to stand that your 3 points allow for faster charge and discharge.
@@Klemeq
No.
"Because of the 5x"
They stated more charge *capacity* per cell, not faster charge *rate* per cell.
There's 5x the material in each cell, so it will hold 5x the energy.
Now, IF the resistance of the cell is lower, (tabless) it will accept more current without heating.
THAT will allow faster charge, but it's nothing to do with the capacity.
That works in reverse for power (discharge).
Note they said "5 times the energy (capacity) 6 times the power"
That implies that the power capacity of the cell (5 times the size) has increased to 6 times the old 2170 cell.
So the percentage increase is 6÷5 = 1.2 = 20% improvement
That improvement would apply to the *pack*
A pack which wastes 20% less from heat (resistance) will be 20% more efficient.
I think that's where the "16% range increase" comes from(?)
Also interesting are the implications for electric flight. Developing the technology and fine-tuning manufacturing to make batteries structural could really reduce weight for flight applications (similar to the wing-as-fuel-tank design of modern planes mentioned during Battery Day).
As a mechanical engineer, this was the most awaited video for me. This is awesome channel.
I agree with your assessment that coolant will go under the cells... Not only does it lower the CG, but the coolant channels could be designed to provide a crush structure to protect against underbody levering or spearing impacts.
Other manufacturers claim they have "structural battery packs", but that just means they have beefy battery cases and transmit some load through them. Tesla is actually using the individual cells themselves as structure and is transferring 100% of the load through the battery.
At 5:14 I think the best way to understand is that the cylindrical (almost honeycomb) battery are used as a column to support compressive stress between the compressed upper panels and the tensioned below panel. It's just like a I beam but in every direction so it give also torsional strength
Fascinating as always. I always wondered what sort of cascade we'll see as weight comes down. Lighter pack means we need fewer batteries to get the same range, but that could also mean lighter wheels, tires, brakes, and other components. Reduce that weight, now we need an even smaller battery, which reduces weight again.
The concept of negative mass is a counter intuitive concept. It should thought of either battery being in structural debt or having a structural credit. This means the battery either requires structural mass or supplies structural mass. The interesting part is that, if you can make structural part out of batteries then you can carry a larger net load.
Agree - "structural debt/credit" is clear, simple, and factual.
coppers thermal conductivity is only better if both electrodes have the same thickness. Al weighs a quarter and has half the conductivity, so if you make the Al Electrode 4times as thick it will weigh the same but have double the thermal conductivity. That is what they did in the end :)
Another excellent analysis. I'm an aerospace/mechanical engineer, and I think your explanation of the advantages of the cells bonded to the face sheet is dead on. This set up is essentially the same as the composite sandwich structures that we use in aricraft and spacecraft to keep the mass low. A typical sandwich construction would use carbon fiber composites with aluminum honeycomb core. The aluminum walls are very thin (a little thicker than aluminum foil), yet they're excellent at tying the load paths of the face sheets together. Great stiffness for the weight.
🤠 Thanks for the input!
This channel is one of my favorite ones to support on Patreon. Jordan’s the GOAT
Your description is very good. The key point that you make is in conveying that the battery shell is in intimate contact with the battery immediately adjacent to the next battery. The same concept is explained when you compare the breaking of a single straw versus the force required to break dozens of straws while each straw is in intimate contact with the next straw. However, in a micro analysis sense, all failures described as 'shear' failures are really failures in compression/tension. However, we use the word 'shear' failure as a generic expression of failure modality.
Thanks for the input!
Jordan, this is EXACTLY what I was referring to for more mech eng focused videos. I should have sent it to you, but I put together a CAD FEA simulation of a traditional battery vs the 42 x 23 electrek leak. Found that the structural pack was around 2.3 times as rigid as traditional pack under same loads. LMK if you want to see it. By the way, you did a great job explaining the shear transfer and polar moment of inertia benefits. Are those your Blender models?? Look excellent!
😁 Yeah, I did the blender on this still image.
Damn! Good information...
I'm actually already done scripting and recording the video after this one. If I can find a place to squeeze in more information, I'll let you know! I still have to go in an do some surgical edits after getting feedback on today's video.
@@thelimitingfactor sounds good! Ping me however if it would be helpful. Sry I forgot to send you that info..
Your videos are the best, and I find that when I see one in my Notifications, I usually pause my TH-cam queue and watch the new TLF instead.
One small note: I found the milk jug example a tad cumbersome.
People intuitively understand polar moment of inertia almost without explanation, no matter how daunting the phrase "polar moment of inertia" may at first seem.
The image that I have seen others use to create that Eureka moment in the learner's mind, is to mention the phenomenon where a figure skater who is in a spin speeds up when she pulls her arms in close to her body.
.
This. I can rest my weary typing fingers now
Structural Pack: twisting a sheet is like bending in 2 dimensions at the same time, and with the honeycomb in it, its act like a very thick sheet (like the honeycomb paper filling from IKEA ;))
So in one direction (bending) it works like an I-beam or H-beam. As explained in the Video, the upper and lower flange is connected with the web. The web take the shear forces and the flanges most of the bending forces. While bending, the outer flenge get streched, the inner one compressed. To torsion this I-beams are weak.
With a honeycomb web, you get stifness in all directions, over the whole area, because the "webs and flanges are everywhere in all directions.
But I think you've portrayed that well enough already. After all, it's about the benefit of it all and how it works out.
This sounded like a poem to me, and I it in mean in a good way
Great video, as an Engineer I agree with the vast majority of your points. A couple of other forces for instance and effects on rigidity and driving behavior come into play too but nothing that conflicts with the overall message of your video. The new design of the 4680 and the new structural design in the vehicle allows further improvements on the castings that have another positive impact on weight as well. In addition this new design opens the door for further improvements Tesla won't start with at version one but for future iterations.
Awesome work, Jordan.
Hello, thanks for the explanation. I realize the numbers are based on the presentation, but they seems very optimistic. Lets say we have the 300Wh/kg new cells. Cell weight with the old cells is 330kg. Now in a typical pack we add 50 percent as you mentioned. That would be 330kg into the almost 500kg on the pack level. Meaning the extra stuff (epoxy, cooling wiring etc) weight is 170kg. With the new 4680 cells we can expect all the extra stuff be much lighter but still, even if it had half the weight, so 85kg, this means to get to the "effective" weight of 300kg on the pack level we have to save 85kg+30kg=115kg of the structural weight. Since the entire aluminum body of a model S is supposed to be about 200kg that seems way too much.
Great point about convection. 🔋 🚀 great video !
thank you for good quality information it's hard to find it without manipulation.
Thank you. Jordan can do a deep dive and still be good to follow for those who are less informed.
Excellent Video again!!!!
Thanks man!
Wow this video in particular really answered a lot of things that I was wondering about. The details about the Rockers becoming redundant in particular has bugged me since battery day.
Recycle of used cells? Page 11:00
It is advisable to consider (aluminum extruded) honey comb structure in separate from the use of cell wall as integral part of the comb. Same way we drop in a cell in our flash light.
I just made a similar point.
5:56
A "drop in" cell (better still, press fit?)
Instant grounding of the case (one less connection)
Recycling just needs the cells fully discharged then either dropped, or pressed out on a jig.
Love your series on batteries
Thank you so much Limiting Factor!
I'm actually watching your videos to understand more about the battery since I've been offered a position in battery manufacturing for Tesla!
Your videos is helpful (even if you are not an expert)
Awesome! I try to make them as accurate as possible and most have been reviewed by actual experts :)
Furniture makers use 2 sheets of veneer that sandwich something called honeycomb. This honeycomb is cardboard, about an inch thick. It is glued to the veneers and there is a solid wood edge along the sides of the panel. This panel can be used for table tops, conference table tops or other structural parts of furniture. It is very strong and light compared to other construction techniques.
Also, there are companies who use thin sheets of metal which sandwich styrofoam, to form structural wall panels in prefab homes. It's the same idea, with a light core and thin structural sheets on the faces of the panel.
The torsional strength is amazing when considering how much material would need to be used to separate if there is a separate frame and non-structural battery pack. Of course, the batteries as a core are not as light as styrofoam or this cardboard honeycomb but the weight savings of using the pack as a structural piece is significant.
What will Tesla think of next, to incorporate structure with some other function? I heard the Tesla cars have air shocks for suspension and that the air tank for it has been incorporated into also serving as a structural cross member in the front of the car. A tube shape has a lot of structural support for both a cross member of the frame and for an air tank and, because the air is amorphous and does not need to be a specific shape, the tank can be long, like for a cross member rib for the frame.
Is there anything else that can double as structure and some other function? Or can one part serve 2 functions other than structure? Or can one part serve as structure plus 2 other uses?
And applications: we can ask, are these techniques the future of all cars? Would the bed of a pickup truck serve as a place for a structural battery pack? What about the floor and walls of a trailer for a tractor trailer (the semi)? And can the roof of a trailer have solar panels? If not for a tractor trailer, maybe for a straight truck? And what if Tesla created some sort of version of blade batteries, built for structural battery packs? Would that save more space than the cylindrical battery? (Place the blade batteries on their sides instead of like a deck of long cards, the way BYD does, so the thickness of the pack is an inch or less.)
Years on and finally a simple discription. I believe i had it correct.
Been looking forward to this one for so long!
Thanks for the video Jordan! It was very insightful. My dad and I were just discussing how exactly they would go about cooling packs and your explanation seems the most plausible. Your videos always have good research/sources and your explanations are very helpful.
🤠 You're most welcome!
Thank you for providing this knowledge for free. I am willing to support you
My personal thinking is that cooling could be (and perhaps will be) done on both top plate and bottom plate.....to ensure more uniform heating/cooling (and thus ensuring uniform aging) through the entire cell.
Jordan,
That honeycomb structure at 5:56 has caught my attention (repeatedly)
I wonder what it's made from?
Megapress casting??
Insulator? Or metal? (Would be an interesting way to aid *fast* construction? "drop" the cells in, no glue!).
If metal, instant "common grounding" for the cell cases? Would that mean only *one* conventional connection needed per cell?
One circuit board, dropped on top, fusing and terminal tabs on the board, press fit onto the cells, no welding!?
Recycling?
If those holes allowed a press fit of the cell casings, just needs a jig and a press to remove the cells after discharge.
Not sure! It looks like some kind of injection molding? I have little understanding of manufacturing techniques. So much to learn! Oh yeah...I agree on 'dropping it in'...covered in the next video. 😁
@@thelimitingfactor
Oops!😉
Another great video. Could you please somehow number the 15 videos in the series? I think I have watched them all but I’m unsure. The first one you suffixed with #1 but non of the others. Keep up the great work in educating us.
I had that issue before, so it's likely a common issue for us viewers... meaning, would probably benefit new viewers that are gonna stumble onto your channel as well.
You can expect many, many more will do that & be thrilled to stay for this awesome education you provide
Excellent explanation of the planned structual battery. I have 4 concerns for it:
1. Crash security?
2. Is repair possible, to exchange spoiled cells?
3. Is use as scond liefe (use of old batterys as stationary battery) possible?
3. Is recycling possible (here you told us your opinion in the video)?
Would be great, if you or someone could check the first 3 points!
A much more robust and simple wiring scheme would be to alternate the orientation of the cells positive up and down. Simple straight connections without the precision required for attaching to the edge of the cells on the same end as the center connection. Thermally conductive but electrically isolating epoxy could mean agnostic orientation. It seems unlikely that the thermal conductivity difference between Al and Cu is meaningful in the short distance between the end of the folded conductor and the top of the cell can. Tesla does have the precedent of the more complicated wire harness but the structural pack offers this option and I hope they take advantage of it.
Double layer circuit board with contact studs and fusing embedded?
Contact by pressure, no welding?
200kg reduction is insane. Thanks for vid (also new supporter on Patreon here and have watched most vids in this series).
Much appreciated! 🤜🏻🤛🏻
Page 9:15 : Yes, excellent thermal transfer - from the core to the bottom by copper leads - only to fall short passing it to inner cell wall ie negative terminal casing. Why? It count on point contacts by a force derived from annealed (soft) copper leads, a problematic electrical connection method that responsible engineers will avoid, so how good is thermal dissipation? Nearly as good as conventional single welded tab? That defeated Tesla’s claimed thermal advantage.
-Great stuff as usual Jordan.
-I don't know if you ever delve into Tesla charging infrastructure, but I'd love your opinion (a video would be be great of course) on the large Supercharger installations in the works (several biggies along Route 5 between LA and San Fran) and whether they may actually be, at least partially, Megachargers for Semi.
-For example check out Harris Ranch. It appears to be a truck stop already, lots of space, permit for 80 Superchargers.
-Also what is the feasibility of Semi using several (four, six, eight) Superchargers to charge in the wee hours when nobody there? Or a setup like the mobile Megapack that was deployed in 2019 at the Supercharger in San Luis Obispo.
-I can give more deets on this stuff if you're interested.
Megacharger.
I've mentioned my hypothesis before.
We've seen a Semi charging at a pair of "conventional" superchargers with the cables connected to a common plug, which was plugged into the vehicle.
If we assume "Megacharger" denotes 1000kW(?), Tesla already has V3 units capable of 250 kW, (currently limited by the car batteries).
Imagine a drive through charge bay with a pair of V3 units on either side, paired to one plug per side. (Similar to a diesel Semi with dual tanks?)
That gives Megacharger performance with proven, modular technology.
As you say, there's no reason a Semi can't "trickle charge" on a single V3 overnight (or one per side).
@@rogerstarkey5390
Love it.
It seems like a no-brainer for Tesla to leverage the Supercharger network in some way to enable Semi to go long distance, at least at first. (but I'm a biased reservation holder, heh..) Not feasible at all locations due to space/accessibility, but I think it would work at some, especially given the small number of Semis in the beginning.
I've heard the goal is for Megacharger to charge at 1.5MW plus. Full charge in... 45 min?
Question: Is it possible to achieve a similar result by somehow connecting six v3 Superchargers to Semi?
Question: Is it feasible (financially, technically) for Tesla to place a Megapack at Supercharger stations, "trickle charge" it at night, use it to Megacharge Semi?
They should use a high density foam in between each cell to help with rigidity and stop fires from spreading if the cells were to catch fire
It's flame retardant epoxy according to Elon
@@thelimitingfactor that makes sense
Well done. Jordan. Thank you.
.....I've never seen the shingles unfolding before like you have at 9:02...source???
Oh man, it was official and from Tesla. Maybe their website? I posted it on twitter months ago but forget when.
Running change to cell count?
Is possible only separation between one cell to the next remains evenly distributed to avoid differential strong vs weak spot leading to structural torsion weakness or tinkles on flat surfaces.
As long as the pack fits in, the shredder doesn't care if it's structural or not. I don't think large-scale recyclers are going to pry out individual cells.
Amen!
My 2 cents is that the first 4680 cells will not be used as a cell to chassis as presented during the battery day. The reason is that they will be used on model Y Berlin that will still have a pack as seen from picture at 5.56. the full cell to chassis is probably going to be used on model S plaid+, cybertruck and roadster, with a cooling plate (for cybertruck and roadster only) on the bottom rather than serpentines cooling channels (needed on Y as the pack height is not indefinitely extendable on a vehicle designed for 2170s).
Thanks for this! I've been wanting to understand this part for some time now.
Wow Jordan that is mind blowing!
And again a brilliant and easy to understand (for once😈) video from Jordan ! I would love to see an interview / collaboration of yourself and Sandy Munro...
Keep well, both of you 👍🍻🍺
Yeah! I need to chat with him!
On the "negative mass", not sure how the number for *cells weight* is sourced, but just a possibly obvious / dumb comment: the sum weight of the 4680 cell cans should be smaller than that of the 2170s, even if the active material weights are similar in the two (energy-equivalent) packs. So the total weight of cells in the 4680 pack would be smaller than the cells in the current LR packs.
There are too many assumptions in that comment to untangle here in the comment section.
We all appreciate you 👊🏼
There might be additional benifit to the Silicon Carbide anode, since it is so strong it might allow increased storage though as structural battery.
the anode is a powder.
@@w0ttheh3ll Every part of the battery can theoretically provide structural support, even the powders within them can transfer forces applied to the cell.
I would question if reducing a lot of what they consider redundant structure around the current battery pack and making the pack a structural member would tend to reduce crashworthiness and increase the risk of battery pack damage and higher possibility of fire in more severe accidents.
And this is what I said when someone wrote an article at Cleantechnica saying that the Roadster 2.0 wouldn't have better handling because batteries are heavy and all that jazz.
Heck! That roadster was made with Model 3 batteries! 4680 cells, cell to structural pack, Cybertruck's 30X Stainles Steel, huge single casting pieces, etc all those innovations didn't exist back in 2017! All those could be added to both the new Roadster for better handling and to the Semi for longer range! And to think even more energy density is being developed (I think I recall Elon mentioning between 400Wh/Kg to 500Wh/Kg to achieve a possible electric plane jet with VTOL capabilities)
I've noticed that the jelly-roll doesn't go to the absolute center of the cylinder. Could the cylindrical space in the center of the 4680 contain something to further facilitate cooling?
This!! I haven't even thought of that.
It might over-complicate the design, but still an extremely valuable insight!
Possibly, there were rumors before battery day that there is an aluminum core in the center of each cell. But, I've heard a lot of rumours. I only share information that has corroboration in some form or another.
@@thelimitingfactor
Jelly donut! 😁
Jordan thanks so much for your extensive reviews and gained knowledge, you are truly an amazing help to the tesla community, thanks brother!
Brilliant animation skills man
I really enjoy your content.
Thank you.
As Frank Spencer of 'Some Mothers Do Av Em' fame would say:-
'Also...'
Because the 4680 battery has a larger cell zize it's surface area to volume ratio is less than in smaller cells.
Since the casing of the cell is made of metal this will likely contribute to a weight saving, though I note that the sheet metal thickness used for the 4680 case seems to be rather thicker than I would have expected to be necessary.
Great series! Thank you!
Great channel! I love your content!
Woot woot, hydraulic press channel!!!
Interesting content, well-presented.
You should start a weekly/monthly Battery News series (not only Tesla)
Wish I had the time! It would get me views, lol. People are Quid Nuncs
@@thelimitingfactor Monthly/ 3-monthly (quarterly) is more doable & relavant...
Maybe even once half a year, so that there is enough big news, to have enough relevant material to cover
@@thelimitingfactor You know, only if you ever feel you wish to have more work :D
Once you expand on how many people create content for this channel, it could work... I see your channel grow A LOT in the coming years.
All the more reason why they can go all in on LFP. I am not sure why on battery day they seemed to indicate that LFP is only for the model 3 and the 25K car?
Because LFP has limited range and customers who are purchasing more expensive vehicles will demand more range.
@@thelimitingfactor How about optional (except for semi and airplanes)? Not enough demand? How expensive would it be to provide the option?
It's a volume calculation (as it's always been)
Length between the axles, width of the vehicle, weight of the vehicle, performance required.
Every pack density/ volume will have a "sweet spot" for vehicle performance.
@@rogerstarkey5390 Ok but I'm talking about cost vs performance. Nickel cells always perform better.
@@red-baitingswine8816
But the material is much more expensive and in short supply.
The high performance cells will be used where weight/ volume reduction is more important that cost.
What a great video! Thank you!
The recycling is of course not done with a chisel but with a large shredder, because it does not care how the battery is built.
👆🏻 Correct
I know Elon's attractive, but 'Business Magnet'?? I think it may possibly be 'Magnate'. :D
Loving the channel, by the way.
Nope! He said magnet....because he attracts business like a magnet, lol.
Thanks man!
Yay!!!! more content, woooohoooo!
Great video, as always Jordan. What is your assumption, as to how 10% mass reduction, results in 14% range increase?
It's directly from Tesla's presentation. The only way this is feasible if it's at the vehicle level.
How would the honeycomb structure look for the standard range you think? Do we know the capacity for a single cell?
I worked it out at one point and I would need to recalculate it. Ultimately it doesn't matter anymore and I didn't keep the calculation because the capacity of the individual cells won't be what drives decision making. It will be cost, trim level, and material availability.
@@thelimitingfactor True! Just exciting to speculate about what to multiply 960 cells with. Sandy Munro seems very ambitious with a 130kwh pack.
I worked out the roll length of a 4680 compared to a 2170 cell.
(Very useful "carpet roll" calculator on line😁)
Assuming the material thickness is the same, when the increased length is multiplied by the respective cell height, the *surface area* of the roll in the 4680 was almost exactly *5 times* that of the 2170.
(Strange that?)
This leads me to the conclusion that the "5x energy capacity" statement on Battery day took no account of improvements in chemistry and was in fact just down to more "stuff" inside each can.
(The "6x power" was down to that increase, plus cell resistance/ tabless design)....?
If that's the case, imagine what happens when chemistry/ materials increase the energy density of that roll material by 20-30 % !!!
600 cells for a model 3 pack?
A *HUGE* weight reduction for the Semi(!)
Great content well presented.
Corrugated cardboard as used in packaging is strong compared to sheets is the same arterial. Structural battery packs use the same principle.
I'd like to see some comment on the potential problems that Tesla is having scaling up and producing the 4680. I have heard things about heat problems, questions around robustness and the yield of the manufacturing process. Any thoughts? Thanks for the great videos by the way, added to my list of 'must watch'
The issues they are running into with the 4680 are typical of any production ramp.
An exercise for the next super market visit!
6 pack of beer (mmmmm beer)
The tops of the cans are held by plastic.
If you pull one can sideways, they all move.
Put one at the bottom, it moves in its own.
Now imagine that plastic on the bottom as well.
Much more rigid, but.... If you push one lower corner, then push the opposite *upper* corner, the cans tilt and slide against each other, knocking the "cube" out of square (stops then "falling over")
Now apply glue to the cans, sticking them together.... Zero movement.
That's where the torsional/ shear strength is coming from.
That's then bonded to the plates, and all forces are transferred across the plate rather than trying to bend it.
Pinch the two plates together at the sides, extremely strong.
It's also the cylindrical shape of the "can".
Cubes wouldn't be as strong (A structural engineer may disagree?)
Imo, I don't think the material inside the can will be stressed (under pressure) at all in this case.
Great explanation!
is a battery cell more, or less dense than water? Place the cooling liquids lower might mean the cells are higher. If cells are more dense than water, CG would rise.
Would the batteries need to be bonded to the top and bottom plate for it to be structural? If you bonded the batteries to each other, effectively you make a battery brick. Then, if you placed the brick inside of a box, wouldn't it then provide structural rigidity to the box?
Both.
Glue them together, that gives torsional stiffness to the *pack* (cell block), then glue the plates to mount the block to the car.
All (most) of the force on the plates would be lateral apart from the actual edge fixings.
I've always wondered about the epoxy, or what have you, on the old pack.
Surely there's some chemical that easily dissolves it and makes it much easier to recycle.
All they really have to do is dump the pack into a grinder and sort things out chemically.
Epoxi melts easy
Cooling on top seems reasonable as it insulates batteries from passenger comparment, Dont want to cool the outside world. Dont want high temps getting to passenger compartment.
I think heat rises in solids too.
Recycling. On the existing vehicles the battery packs can be removed from the vehicle and sent for recycling. With the structural batteries this probably means the vehicle will need to be sent back for recycling. This To my mind is good, it means that the front and rear castings can be salvaged at the same time. Ok the alloy could change from time to time but tesla will know what is in every casting it recovers. I think we will see all Tesla factories having a recycling facility soon to make the most of the existing materials. Humn the above also goes for the glass and probably many other elements. Is this perhaps the way all recycling should be?
Does anyone know the repercussions for TRP? Curious since cells arent separated by section anymore
That torsional rigidity definitely gave Sandy some... torsional rigidity.
😀 I was certainly doing a full salute
What about two battery packs to cycle infanate power with power loss recycling systems
Hexagonal honey-comb like battery would make strongest sructure for each one , and moreover if its connetced to each other within a superstructure
How goes scaling of the 4680 cell production?
WOW, amazing, thank you!
I'm here for the theme music
Great explanation
There may be considerable room for innovation WRT breaking apart the battery pack for recycling.
Excellent video. however how does Tesla ensure that the pack is not punctured from below? After all, it will lose one layer of material.
It's a metal plate
Why can't cells be designed using silicon - with room in the cell/layers to allow for greater expansion?
I was under the impression that the fragility of the cell wiring was making it an overcurrent fuse. If one cell overcharges the fusible link would isolate that cell from the system.
Yup, but that cell was originally designed for laptops. There are other ways to isolate cells.
Seems like Tesla will start in Texas and Berlin with regular 21700 packs, to soon upgrade Berlin to work with the 4680 structural battery pack once they solved the 4680 quality
Mr Musk is unrivaled, he has a lightning-fast mind like his products and the competition knows it too it would be nice if he designed a car with a panoramic floor as the roof unique and futuristic project the fox
Thank you!
Great job really
After your video I am now wondering why the batteries need cans. Put the roles into an an epoxy honeycomb and fill the cells with electrolytes.
Side reactions. That's why batteries are high nickel cans - resistance to corrosion.