Correction 1: On the slide from 09:10 to 09:25, the note says "Tesla still isn't coating the cathode with a wet process." It should say "Tesla isn't coating the cathode with a dry process." Correction 2: At 5:55 I say ohms rather the milli-ohms. Obviusly I meant milliohms given that's what's showing in screen. Note: One thing I still need to look into is why the 50% thicker cathode than a 2170 results in only a 15% increase in capacity. I'm guessing that it's partly due to lower Nickel content and higher porosity. It could also be that Matt Lacey was comparing to a Pansonic cell, which may use a thicker cathode than the LG cell. When I know more, I'll share.
Have you heard if there is plans to reduce the internal resistance of the tabless current collector system? Like chemical copper surface bonding or perhaps a micro textured surface nurling of a new copper alloy that doesn't oxidize as much?
There is a major mistake / omission here... You are comparing APPLES TO ORANGES. One battery is structural. The other battery is not. You have to subtract the weight of the displaced portion of the vehicle's structure. Let's say for example, you are able to remove 1/2 lb of steel for every 1 lb of battery that you install, then 1-1/2 = 1/2, and 268 wh/(1kg -1/2) = 268wh / (1/2kg) = 536 wh/kg! Now this is just an example and I have no idea how much weight is displaced, or even if there is any weight displaced in this first version of the 4680, but YOU CANNOT MEASURE WH/KG UNTIL YOU KNOW HOW MUCH WEIGHT IT DISPLACES.
@@TheNativeTwo He is absolutely aware of that and has discussed that multiple times in the past and even in passing several times in this video. This video discusses the penalty for thick cans. As you can see, much of the problem comes from the current chemistry, which is not quite on par yet. This is something that can be changed in future iterations.
my suggestion would be that while you increase the thickness by 50% you wont have 50% more cathode in the cell, since the cathode is thicker you will not be able to fit in as many coils into the jelly roll. A more important metric to consider is the cathode to current collector ratio, I suspect when looking at this metric you will end up closer to the 15% capacity increase.
Micro-ohmmeters cost thousands, I ran into this problem in college when designing a land speed record EV battery pack out of A123 cells. One solution is to calculate DCIR from voltage droop DCIR=ΔV/ΔI
Jordan, will you do a recap video on battery chemistry? Some of the things to cover are: "Where is lithium hydroxide used?"; "Can most of the transition metals (singly) be used in the cathode?"; "Which other elements can be used (theoretically) as ions to shuttle between anode and cathode?"; "What forces attract and compel the ions to move from one side to the other?; "Can an element, like aluminum, really be forced to give up more than one valance electron?" "Why don't electrons go through the separator?"; "Where are the electrons stored when they leave the anode, during discharge, and go (externally) to the cathode?"; "Do electrons move only a few tens of microns; but, their accumulated charge is felt (as electricity) from the anode (externally) to the cathode?"; and other simple questions.
Minor correction to an informative video: silicon is the element, silicone is archaic but very common synonym for siloxane, the type of polymer. It was named by someone who had the structure wrong and thought it had Si double-bonded to O, silicon + ketone = silicone, instead of Si-O-Si-O chains, but the name stuck.
The problem is that this is comparing cell energy density. And thats not an appropiate comparison, it should be comparing similar capacity battery packs. Cooling is the biggest advantage for 4680. And that makes the pack lighter. Add structural advantages and that removes weight from the final pack.
Power is a very tricky topic and highly doubt a university could reconstruct this. Power is usually based on the DCIR and the max current values. Max current values takes some time to establish. The Power capability will of course be increased with a tabless design since electrodes travel less to the terminal of the cell and there other factors. Interesting would be the quick charge capability for SOC 8-80% but that will be tough to get because usually quick charge patterns are developed specifically in order to ensure quick charge can be done for a certain number of cycles (~300-400)
I’m not sure about what is the biggest elephant in the room, but for me it’s the number of cycles combined with capacity degradation over time. I hold these as somewhat independent variables (they are of course linked a bit) but useful battery life will be more important to the consumer than initial energy density. Imagine where battery technology will be in 2030 and 2040. Do your viewers think it will be better, the same as today, or worse? Thank you for the videos.
Sure thing Pedro! Yeah, cycling data is important. But, they wouldn't have put it in the vehicles if it didn't meet their spec (whatever that is). Min 800 and max 1500 cycles.
Better, same as today, or worse? I think the answer is yes. You have to figure that by 2040 even the cheapest vehicles on the road will mostly be some flavor of EV and that the startup wave is really just beginning. To get EVERY vehicle on the road running on batteries means sure, there will have to be many many big breakthroughs. Some of those breakthroughs will likely be dramatic improvments on energy density, or a whole new chemistry that is more reliable and cheaper to produce... but another possibility is someone invents a new super cheap battery/manufacturing process that is just absolute garbage in terms of reliability, but its so bloody cheap that nobody cares because it allows the creation of an EV "Yugo". Or maybe theres a super "green" battery that is all eco-friendly materials... maybe its worse performing but certain customers will want it so they can virtue signal. Or maybe the cheapest thing is to literally just keep making the same batteries we have today at insane scale.
There is a major mistake / omission here... You are comparing APPLES TO ORANGES. One battery is structural. The other battery is not. You have to subtract the weight of the displaced portion of the vehicle's structure. Let's say for example, you are able to remove 1/2 lb of steel for every 1 lb of battery that you install, then 1-1/2 = 1/2, and 268 wh/(1kg -1/2) = 268wh / (1/2kg) = 536 wh/kg! Now this is just an example and I have no idea how much weight is displaced, or even if there is any weight displaced in this first version of the 4680, but YOU CANNOT MEASURE WH/KG UNTIL YOU KNOW HOW MUCH WEIGHT IT DISPLACES. Edit: I also want you to know I appreciate your analysis efforts. You make great videos. But here is where there is something special that needs addressed. On battery day Elon was very excited to announce the structural battery. He made comparisons to airplane wings carrying fuel. Yet it seemed to just go over everybody’s head the true implications of a structural battery. The first principals implication of a structural battery is INFINITE energy density. Of course, that’s the ideal, and in the real world that’s not even a possibility. But what is possible? How far have they taken it thus far? This analysis is far more interesting and fundamental than doing an analysis of the battery chemistry. There is no battery chemistry that has a first principles energy density of infinity.
@@thelimitingfactor yes, it is. But without factoring that in, the comparison isn’t accurate. At least you should mention that so people know that it’s actually better than what you are stating.
@@thelimitingfactor I am an engineer and sometimes in engineering we give a simplified model to show how something works. Same thing in physics. For example, we do ballistic math but assume no drag. This is called first principles thinking. The benefit of doing this is to remove the complications and understand how the underlying system works. We will use >> (much much greater than) many times to see how a system works at the extremes as well. So here is a simpified model of the true benefits of a structural battery and why it can be the most important factor for Tesla’s new batteries. Suppose you want to hike across antarctica. To do so, you must carry all of your food (fuel). As you travel, you are able dispose of your waste, your consumed fuel, so your pack gets lighter as you travel. This is like a gas car. It burns the fuel and produces smoke. Now consider an extra requirement. Let’s say you had to pack out your waste when you hike. Your pack doesn’t get any lighter and weighs you down the entire time you travel. This is like an electric car. It has to carry it’s spent batteries (fuel) as it travels. Now consider the structural fuel source. This is like being able to replace your bones with rechargable nutrient giving human batteries. Now you don’t have to carry your food at all. You just charge up your bones, walk until you are empty and recharge them. This is like an electric car with a structural battery. A car needs a frame, replace the frame with a rechargeable frame. So fundamentally, what do we mean by energy density? What’s the utility of that measurement? Well, we can use it to figure out how much fuel (in weight or in volune) we need to CARRY. Well, in the case of the structural battery, in a perfect world where 1 lb of steel structure can be replaced with 1 lb of battery, you don’t need to carry ANY fuel. So what is your ENERGY DENSITY CARRIED? 248 wh per zero kg. That’s an INFINITE energy density. That’s the first principles theoretical limit of a structural fuel source. Now of course in the real world, you have to consider so so so much more. But you cannot ignore the benefit, the change created, from using a structural battery.
what about safety? is the 4680 safer to charge and discharge than 21700s? Cycles/lifespan? guessing there will be more specific information about these qualities in the future?
I've been planning to try and DIY my own lithium cells at home using a 3d printed roller/consolidator, and have slowly been gathering materials, and learning as much as I can about their construction. I have no idea why I want to do this.
What about power density from a Supercharging point of view? Would these Texas vehicles already be able to sustain higher power for longer via a software update leveraging that majorly reduced resistance?
@@thelimitingfactor We need someone with ScanMyTesla or similar to do a charging video to see if Tesla is limiting charging performance to not Osbourne themselves or that's what they can do Quite easy to notice by looking at the voltage profile and comparing 4680 vs 2170, maybe will only happen when Berlin pump them out and Bjorn get's one And that also will answer the internal resistance question
Any chance Tesla is saving the better more expensive chemistry’s for cyber truck and semi since it will be more energy intensive to operate. While using cheaper more familiar chemistries to improve margins and keep specs consistent on model y to not hurt sales/make customers feel jaded? As it stands right now Tesla is still range/efficiency king so maybe it made more sense to focus on keeping range consistent but reducing price of manufacturing or atleast keeping it the same in attempts to battle inflation.
ENERGY DENSITY VERY DIFFICULT TO COMPARE Because of the structural purpose of these cells a Cell to cell comparison is not really relevant. Even pack to pack comparison is not relevant as there is also a differencein model Y body weights. About the only way to properly compare would be comparing the weight of Tesla structural battery body-in-white frame with pack fitted, with a non-structural body-in-white frame with 2170 pack fitted. The weight used for the effective pack density of the structural battery would then be the (non-structural pack density) x (non-structural Kwh) + (difference in weight between the two fitted body-in-whites). Then divide by structural pack's kWh.
Hmm, I wonder in battery pack density calculations whether typically the packs are weighed wet (with coolant liquid). Using dry weights could be misleading if there is a difference in amount of coolant required between different pack designs. And is dry or wet measuring consistent across brands. In testing it is amazing how a simple task turns out to be very complex when you think about it fully.
I believe Tesla is new to the cell game and it is very very difficult to handle higher Nickel based cells. From safety issues to degradation. These difficulties are the price you pay for more capacity of the cathode material.
@@thelimitingfactor sorry I guess I missed it, but am I understanding correctly this is a (N)ickel(M)anganese (C)obalt mix? If so then something is not adding up. On battery day, the battery was supposed to have a 16% increase in range while the entire manufacturing with the new Giga Casting was supposed to have a 54% increase in range? What happened, what am I not understanding?
I wonder what the density is for the Twitter battery? The positive and negative energy is never ending. Probably would last over a billion miles with one charge from an Elon Musk Tweet. If Tesla could only harness that think of the power. 😂
The more of these analyses I see, the more I'm encouraged to conclude that the 4680 has not delivered on its promises. Tesla seems to have gotten little out of this initiative beyond a somewhat more convenient form factor.
so if you take into account the cell can is heavier for the structural battery pack the the gravimetric energy density is about the same as the 2170 so why do you lead with the energy density is disappointing just dumb.
While you make a great point of R&D self-funding, it certainly wood be nice to see some of the cost reductions turned back to the customer. Elon keeps talking about EVs for the masses and saving the world. Right now these cars are only for the upper middle class and above. How long do we need to wait to see them for all? Personally, while I can see a day where we're talking about autonomous vehicles, that's a generation away IMO.
Great video and very nice to give the shout out to Matt Lacey. I am glad we can finally put all the mystery software locked theories to bed. It will be fun to see the 4680 architecture evolve over the years.
Re: cobalt, Redwood Materials announced within the last couple days that 100% of the cobalt they’re going to supply to the new Panasonic factory in Kansas will be recycled cobalt. Not sure if it’ll be a significant percentage of the total cobalt needed, but still good to hear.
Jordan: excellent info; a minor nit: at 5:55 you mentioned the internal resistance - it should be 7 thousandths of an ohm, (7 milliohm) not 7 ohms. Thank you for doing such comprehensive analysis and sharing it with us all!
Excellent work as always. I've been telling people from the beginning that it was unlikely there would be a future unlocked capacity upgrade for existing 4680 Model Y's, now I can point to definitive proof.
"Don't let the perfect be the enemy of the good" Very important insight. It's about the utility to the user - and that utility includes a low price. It's also about the utility to the company - and that utility is a profit margin that allows investment in further optimization and research as well as rapid scaling.
While we would like to see all specs improve: less weight, more range, etc. It’s true that reliability and production rate is what matter most at the moment. Tesla doesn’t want to get millions of recalls in a few years on batteries or casting, that could destroy the company. It’s better to play it safe with the new technology until they have a lot of data on the failures modes.
100%... The combo of castings, structural battery packs and 4680s are all entirely new and so its imperative that Tesla play it safe. This will all get refined over time but lets take the changes out nice and slow so that there are no recalls. These components are clearly not designed to be replaceable and so they must get it right first time or the car is a writeoff. Lower efficiency right at the get-go is an acceptable tradeoff for me.
Yeah. The importance of range drops off after a certain point, maybe somewhere around 300-500km, when you simply *have* enough range for most of the things you'd want to do, from daily commutes to road trips. Your average consumer also isn't going to care that much about how you get that range, whether it's a by increasing the size of the battery until you are left with a 2.5t hatchback or by optimizing the energy efficiency of everything you can get your hands on. Ultimately the only thing that matters once you cross that threshold in range, is reliability (for older/used vehicles with data on them), if the vehicle is even available for purchase and how much it's going to cost.
From your initial tear down of the 4680 the thickness of the cell walls looked like overkill. I'm thinking of a hollow door that is amazingly strong yet its center is an empty cardboard honeycomb. These cells are full, so less crushable and they are tightly packed together, doubling up the metal thickness where two cells touch. Then any void is filled with structural foam. Maybe they can reduce weight by making the cell walls a lot thinner without losing much of the strength. When you look at a modern soda can, it is paper thin but its shape and the content give it rigidity. I would think it would take the weight of a man. I'm suggesting there may be some wiggle room in the cell wall thickness is this something that could be tested in a computer?
Professional and packed with details. I usually listen to my videos and double speed, but I had to slow down this video to take it all in. Keep up the good technical work!
Im not totally surprised that the Texas Y is heavier. One thing Ive been thinking is that the current Texas Model Ys will need to be as close structurally to other Model Ys as possible to maintain part commonality. This means that some of the structure of the rest of the vehicle is redundant to the pack because it has to exist for other versions and share common mounting points. I feel like we wont see a full optimization of the total structural design until all lines are using structural packs and everything is streamlined, or unless there is a whole new vehicle designed from the ground up to only use the structural pack and gigacastings.
I could be wrong, but It seems current 4680 ramp priorities are Now: More (production line speed), Cheaper (supply chain), and Later: Safer (electrolyte chemistry, cathode materials), Better (increased volumetric and gravimetric energy density, longer cycle life), Faster (higher charging rates).
I like 'Safer' also, and wonder where that fits in the Tesla priorities schema. Does safer chemistry trump efficient mass/density? How much safer is the 4680 chemistry? Maybe it's a significant factor.
So Tesla's answer to competition is increased range by reducing weight and making manufacturing cheaper. And we should see those advantages in the next couple of years.
you have to compare the entire 4680 pack vs the entire 2170 pack for a fairer comparison because were not considering the impact of the structural design of the 4680 pack vs the 2170 pack. Im not sure what weighs more, the sum of the extra thickness of the 4680 cells or the weight of the added structural elements for the 2170 pack?
The big gain with 4860 vs 2170 is the price on the pack. Tesla make 8 batteries 4860 in the same time than 1,5 2170. And, on the batteries pack, you can remove (2976-828)×2=4296 welding points and, you remove 2976-828=2148 movements. This is the big gain now estimate 5.500$. Gen 2 and 3 will be better but, in next years but not now. 2170= 96×31 batteries and 4860= 92x9 batteries
Can thickness increase is also due to thermal propagation requirements. The higher energy of the 4680 also means that more energy would be released in case of thermal runaway etc. Therefore the thicker can thickness also provides more stability and helps to account for the higher energy content which could have the potential otherwise to ignite other cells in its vicinity
I had very high hopes for the 4680 cells. This initially seems disappointing. But when you factor in the knowledge that this is teslas first time manufacturing batteries, it’s actually pretty impressive that they’re able to get close to established battery manufacturers. I take this as a good that they will eventually get there. But of course, other battery manufacturers aren’t going to sit still. Tesla doesn’t have the battery advantage I thought they would. But, at least we can be sure they will not be subject to the bidding wars to come where battery makers charge exorbitant amounts as demand increases.
Tesla is thinking about basics and stays flexibel for other chemistries but could produce more affordable in big scale and have reserve in much better resistance/efficiency with thermal impact by fast charging - indepandent from chemistries - better structure thsn small cells [but LiFePo comes up with also better form and cooling] but flexibel in chemistry for faster charging and high density e.g. silicon/graphene/sulfur options. Step by step. O course Elon tells fairytail lines of the future but it needs time like all other stories. Imagine all goals come true and double the timeline - than it could be near at reality of products.
The high hopes come if you are new to batteries. I am sorry but there is unfortunately not a quantum leap in battery development. Battery is always a continous optimization. Trust me I work for one of the top 5 cell makers directly in Asia for 10 years. Made cells for all of the big OEMs.
Just a point on the can thickness, Yes your loosing density at the cell level due to the thicker wall, but I think it's fair to say your gaining that density back in terms of weight savings in the finished product structural pack. It's designed to operate as part of a system not as a individual component.
sometimes as a tesla investor, we expect too much. Tesla just achieved to build a world-class battery totally on their own, on par with the industry leading companies that have been doing batteries for decades. But many people see this as a disappointment. I guess I kind of understand, because of the things elon said at battery day.
Theyve literally already acheived 90% of the battery day announcements, and people are disappointed because they arent 100% there yesterday and already delivering on rumors. 🤣
@@patreekotime4578 They also fail to realise new things take time to mature, there are iterations to go yet. It's like the numpties who keep thinking a starship test article is somehow the final design.
Just a guess, but wouldn't there be an upper limit to cathode thickness for a wet process due to the necessary evaporation of liquid from within the cathode layer? At the very least a thicker cell should increase drying time and make a wet process less efficient for thick layers
Oh boy, there are a lot of challenges, and evaporation is one of them! The interesting part is how to get around it... Use different viscousities and different material mixes to create two layers at once. Otherwise you have to do multiple drying passes.
Realized or Unrealized 4680 battery, it's a great EV period...I have 3 Tesla: 2 MY LR and M3, sold my MBs in lieu of Tesla, not going back to ICE cars again....now my friends envy me...
Rather disappointing... What would really bring down costs is increasing energy density. You triple the energy density, you need a third as much batteries, 66% cost reduction right there. Also less weight, less volume.
So Tesla reduces weight due to the structural battery pack. However they have to make the cans thicker. So they get there 10% extra weight for the batteries. For a 70kwh battery that is .1*70000/269=26 kg. That is not too bad. I wander how much weight Tesla plans to reduce on the long run on the structural pack.
So, out of all breathless announcements during the last Battery day, only cost reduction was real. (FWIW, I expected greater internal resistance reduction from tabless design; obviously, I don't know enough about the topic.)
I dont understand how peoples expectations for the first mass produced 4680s were that they would magically beat the industry leaders right out of the gate. One of the major points of battery day is that they showed the potential once they leverage ALL of the different strategies they are working on, but that those strategies were not all coming together at once. As we already knew that most of the chemistry-related improvements werent happening yet, expectations should have been somewhat tempered IMO. And really, honestly, if they didnt make any other improvements, if they stopped working on R&D today, just beating the competition on price is enough.
I am a cell design engineer. The cross-section image of cathode electrode greatly confuse me. The thickness of 4680 is 180 micro meter for double layer? but I cann"t see aluminum foil. If it is one side thickness? It is 2-3 times of the common used design. Hope your reply.
I love your video very much and I learned many things from them. I read many papers introduced in your video. Thank for that. I have several years of experience for EV cell design and manufacture. Hope and glad to do something for your video if necessary.
I disagree with your assessment of the can thickness. The cell is a pressure vessel. Pressure vessels with larger diameters need a thicker wall to hold the same pressure. The “hoop stress” is equal to Pressure * Radius / wall thickness 10.5/0.25 = 42 23/0.55 = 42 The 4680 has identical pressure capability to the 2170. And the 4680 packaging should still be a lower percentage of the cell mass compared to 2170.
Yeah, it would take a whole video to go through that. You're partially correct. People always oversimplify batteries because they see one piece of the elephant.
Does the heat sinking capability of the Tabless Electrodes give the 4680 battery a serious advantage over the Panasonic 2170 and the 5 tab Panasonic 4680 cell?
I think the biggest question is how many cycles does it have... that's what matters most if you have a battery that last 1 million miles then you no longer have to worrie about hurting battery and have peace of mind your not going to need to replace battery once you finish paying for the car
Five tab design is a lot easier. From memory, the patent application for the tablets electrode wasn't strong. So I think there's wiggle room there for other people to do it
@@fredbloggs5902 Right but my understanding is that the conditions are that the other company allow Tesla to use their parents too and I'm not sure whether other companies are open to that.
Рік тому+3
Great video! I’m thinking of buying a model Y within the coming years and the battery day presentation has been in the back of my mind all the time thinking that Ím going to wait for the new version before buying one. Really nice to finally hear someone talking about all the aspects of the new platsform and link it to the battery day presentation!! I know you have limited knowledge about the exact future of tesla around when we can expect to see the full pontential of battery day and such but the I depth review of the current battery cells is very awesome to get. So thank you!!
I was in the same mindset on Battery day. I decided to go for a MYP and took delivery in February 2022, and settled for a Freemont build. I already put 13k miles and since I have solar I paid 0 electricity, and 0 maintenance or repairs, knock on wood. It only consumed about 3800kwh which for a 3.5s 0-60 car seems unreal. Had a MB previously and this is the best car I ever own. I figured I will keep it until the cybertruck is readily available at a decent price, which will definitely take a while.
nice. pretty much the conclusion on the 4680. Turns out that the reason the why the AWD vs LR weighs the same but different capacity/range is because of Panasonic's use of silicon. Weren't for that, the max range or battery capacity would be the same for both.
244wh/kg for Tesla's 4680 is disappointing. They need 310+Wh/kg or 110Wh/cell to compete with CATL Qilin in the future. Tesla is way behind and can't even ramp it up. They are already behind schedule by 1 year. Tesla please do something. But i guess Elon is to busy managing Twitter. lol
11:00 The "power" factor likely has more to do with the upcoming Tesla Semi truck and Cybertruck than it does with the Gen 2 Roadster and current Plaid lineups since high, steady torque from high, steady power is required when towing large loads up hills and mountain ranges during long-hauls. Though there are no immediate plans to use the 4680 in the initial Tesla Semi truck targeting intra-city consumer goods distribution, it will likely be the go-to battery for all Tesla platforms, including Powerwalls and Megapacks, once economies of scale drive down cost ... right about the time when interstate long-haul shippers will start getting their Tesla Semi trucks.
I really like the video and the work, but the energy density figures are a bit underwhelming. This means this has inferior energy density to the LG M58T by a decent margin, rather than being to close to on par. To be fair though, structural designs do provide a large amount of benefit, and the chemistry differences do make a large difference. Finally, another thing that does actually dissapoint me is how high the power losses are for the cell. Getting 90% of your rated capacity at 1C discharge rates is honestly quite poor when considering cells like the Molicel P45B do far better.
That's because the Molicel is a high power cell rather than an energy cell (note that it has lower energy density) Besides, you really need to test the cell rather than go off the marketing material, and test it on the same rig in the same conditions. Beyond that, on power, it depends on whether you're talking 30 second peak power or full discharge. Those are different situations that are dependent on different variables.
Interested to see the video comparing the blade cells, LFP is still the chemistry that makes the most sense to me atm especially as they improve energy densities using it.
Is the gravimetric energy density that important? In an airplane, battery weight is critical. In the car, a high volumetric energy density or a high energy density per base area is important in order to be able to install as much cell volume as possible with a limited wheelbase. 80 mm high cells allow more volume in the battery pack than the 70 mm high cells. BMW even plans 95 - 120 mm high cells. These higher cells have even lower kWh costs. What Tesla plans above the 4680 is not yet known. Tesla doesn't need to admit that either.
For the structural battery comparison to non structural battery you would have to include the structure in both cases obviously. So basically the 4680+floor of car VS other + floor of car.
Well get to it then! 🤣 Go get a fresh 4680 from Fremont and likewise from Nevada and put them through their paces. Be sure to share the results with us.
From my undersyanding with the design of the tabless electrode and surface area advantage i cant see why they are not 46 x 120mm or even longer.If it could be double the length in an 65mm can i think production speed could be halved for energy output! I know they have done their calculations but now being 3 years along since initial announcement i cant help feel in hindsight that they could have made the cell bigger and therefore stronger as well in respect to more rigid as being longer would make it far more rigid ! Anybody got any thiughts on this?
Some may think that the cell content (the "jelly roll") should take some of the forces exerted on the can. They reason that the content could increase the can's rigidity. Stresses on the "jelly roll" could cause cracking and other defects of the "jelly roll"; so, not a good idea.
Tesla's 4680 cells are a huge disappointment, to say the least. GM's Ultium batteries have 272Wh/Kg, today, and GM is looking to release a solid-state battery with partners, that has twice the capacity of their Ultium NMCA batteries, in 2-3 years. Tesla will fall way behind as they cling to a dud battery.
Faulty logic. Tesla is using the same 272Wh/kg batteries in China Modely Ys. Yet, they're switching to the 4680. Why? Cost and scalability and long term options for energy density improvements. Edit: Also, solid state is bunk for now. There are already solid state batteries in vehicles and they perform the same as liquid electrolyte batteries. But, they cost a lot more.
Correction 1: On the slide from 09:10 to 09:25, the note says "Tesla still isn't coating the cathode with a wet process." It should say "Tesla isn't coating the cathode with a dry process."
Correction 2: At 5:55 I say ohms rather the milli-ohms. Obviusly I meant milliohms given that's what's showing in screen.
Note: One thing I still need to look into is why the 50% thicker cathode than a 2170 results in only a 15% increase in capacity. I'm guessing that it's partly due to lower Nickel content and higher porosity. It could also be that Matt Lacey was comparing to a Pansonic cell, which may use a thicker cathode than the LG cell. When I know more, I'll share.
Truly great work as always. Thank you so much.
Have you heard if there is plans to reduce the internal resistance of the tabless current collector system? Like chemical copper surface bonding or perhaps a micro textured surface nurling of a new copper alloy that doesn't oxidize as much?
There is a major mistake / omission here... You are comparing APPLES TO ORANGES. One battery is structural. The other battery is not. You have to subtract the weight of the displaced portion of the vehicle's structure. Let's say for example, you are able to remove 1/2 lb of steel for every 1 lb of battery that you install, then 1-1/2 = 1/2, and 268 wh/(1kg -1/2) = 268wh / (1/2kg) = 536 wh/kg! Now this is just an example and I have no idea how much weight is displaced, or even if there is any weight displaced in this first version of the 4680, but YOU CANNOT MEASURE WH/KG UNTIL YOU KNOW HOW MUCH WEIGHT IT DISPLACES.
@@TheNativeTwo He is absolutely aware of that and has discussed that multiple times in the past and even in passing several times in this video. This video discusses the penalty for thick cans. As you can see, much of the problem comes from the current chemistry, which is not quite on par yet. This is something that can be changed in future iterations.
my suggestion would be that while you increase the thickness by 50% you wont have 50% more cathode in the cell, since the cathode is thicker you will not be able to fit in as many coils into the jelly roll. A more important metric to consider is the cathode to current collector ratio, I suspect when looking at this metric you will end up closer to the 15% capacity increase.
Your videos are terrific. You provide a very careful analysis of the 4680 product that clarifies performance potential. I love it!
Sure thing man! 🤜🤛
Rockstar episode. Thanks, Jordan!
Micro-ohmmeters cost thousands, I ran into this problem in college when designing a land speed record EV battery pack out of A123 cells. One solution is to calculate DCIR from voltage droop DCIR=ΔV/ΔI
Great information, great presentation.
🤗SHOUT OUT TO MATT
FOR HIS HELP … and Jordan I specifically remember you saying that was an estimate !!!
Thanks for the video, you might also check the ICP results for the cathode composition it is more accurate than EDX.
Jordan, will you do a recap video on battery chemistry? Some of the things to cover are: "Where is lithium hydroxide used?"; "Can most of the transition metals (singly) be used in the cathode?"; "Which other elements can be used (theoretically) as ions to shuttle between anode and cathode?"; "What forces attract and compel the ions to move from one side to the other?; "Can an element, like aluminum, really be forced to give up more than one valance electron?" "Why don't electrons go through the separator?"; "Where are the electrons stored when they leave the anode, during discharge, and go (externally) to the cathode?"; "Do electrons move only a few tens of microns; but, their accumulated charge is felt (as electricity) from the anode (externally) to the cathode?"; and other simple questions.
I did a "how a battery works" video that covers some of these. Worth checking it out if you haven't!
Minor correction to an informative video: silicon is the element, silicone is archaic but very common synonym for siloxane, the type of polymer. It was named by someone who had the structure wrong and thought it had Si double-bonded to O, silicon + ketone = silicone, instead of Si-O-Si-O chains, but the name stuck.
I know, sometime I don't speak perfect. Try doing a hundred hours of video and not making a mistake.
@@thelimitingfactor I understand completely. No complaints here.
So you mean that the lady didn't have her breasts enhanced with silicon?!
The problem is that this is comparing cell energy density.
And thats not an appropiate comparison, it should be comparing similar capacity battery packs.
Cooling is the biggest advantage for 4680. And that makes the pack lighter. Add structural advantages and that removes weight from the final pack.
See the pack video I just released today.
Power is a very tricky topic and highly doubt a university could reconstruct this. Power is usually based on the DCIR and the max current values. Max current values takes some time to establish.
The Power capability will of course be increased with a tabless design since electrodes travel less to the terminal of the cell and there other factors.
Interesting would be the quick charge capability for SOC 8-80% but that will be tough to get because usually quick charge patterns are developed specifically in order to ensure quick charge can be done for a certain number of cycles (~300-400)
Another thing I think I need to do a video on. Just getting my head around power.
I’m not sure about what is the biggest elephant in the room, but for me it’s the number of cycles combined with capacity degradation over time. I hold these as somewhat independent variables (they are of course linked a bit) but useful battery life will be more important to the consumer than initial energy density.
Imagine where battery technology will be in 2030 and 2040. Do your viewers think it will be better, the same as today, or worse?
Thank you for the videos.
Sure thing Pedro!
Yeah, cycling data is important. But, they wouldn't have put it in the vehicles if it didn't meet their spec (whatever that is).
Min 800 and max 1500 cycles.
Better, same as today, or worse? I think the answer is yes. You have to figure that by 2040 even the cheapest vehicles on the road will mostly be some flavor of EV and that the startup wave is really just beginning. To get EVERY vehicle on the road running on batteries means sure, there will have to be many many big breakthroughs. Some of those breakthroughs will likely be dramatic improvments on energy density, or a whole new chemistry that is more reliable and cheaper to produce... but another possibility is someone invents a new super cheap battery/manufacturing process that is just absolute garbage in terms of reliability, but its so bloody cheap that nobody cares because it allows the creation of an EV "Yugo". Or maybe theres a super "green" battery that is all eco-friendly materials... maybe its worse performing but certain customers will want it so they can virtue signal. Or maybe the cheapest thing is to literally just keep making the same batteries we have today at insane scale.
There is a major mistake / omission here... You are comparing APPLES TO ORANGES. One battery is structural. The other battery is not. You have to subtract the weight of the displaced portion of the vehicle's structure. Let's say for example, you are able to remove 1/2 lb of steel for every 1 lb of battery that you install, then 1-1/2 = 1/2, and 268 wh/(1kg -1/2) = 268wh / (1/2kg) = 536 wh/kg! Now this is just an example and I have no idea how much weight is displaced, or even if there is any weight displaced in this first version of the 4680, but YOU CANNOT MEASURE WH/KG UNTIL YOU KNOW HOW MUCH WEIGHT IT DISPLACES.
Edit: I also want you to know I appreciate your analysis efforts. You make great videos. But here is where there is something special that needs addressed. On battery day Elon was very excited to announce the structural battery. He made comparisons to airplane wings carrying fuel. Yet it seemed to just go over everybody’s head the true implications of a structural battery. The first principals implication of a structural battery is INFINITE energy density. Of course, that’s the ideal, and in the real world that’s not even a possibility. But what is possible? How far have they taken it thus far? This analysis is far more interesting and fundamental than doing an analysis of the battery chemistry. There is no battery chemistry that has a first principles energy density of infinity.
No, I just didn't want to go on a dog leg. It's more complex that what you're illustrating there.
@@thelimitingfactor yes, it is. But without factoring that in, the comparison isn’t accurate. At least you should mention that so people know that it’s actually better than what you are stating.
@@thelimitingfactor I am an engineer and sometimes in engineering we give a simplified model to show how something works. Same thing in physics. For example, we do ballistic math but assume no drag. This is called first principles thinking. The benefit of doing this is to remove the complications and understand how the underlying system works. We will use >> (much much greater than) many times to see how a system works at the extremes as well.
So here is a simpified model of the true benefits of a structural battery and why it can be the most important factor for Tesla’s new batteries. Suppose you want to hike across antarctica. To do so, you must carry all of your food (fuel). As you travel, you are able dispose of your waste, your consumed fuel, so your pack gets lighter as you travel. This is like a gas car. It burns the fuel and produces smoke. Now consider an extra requirement. Let’s say you had to pack out your waste when you hike. Your pack doesn’t get any lighter and weighs you down the entire time you travel. This is like an electric car. It has to carry it’s spent batteries (fuel) as it travels. Now consider the structural fuel source. This is like being able to replace your bones with rechargable nutrient giving human batteries. Now you don’t have to carry your food at all. You just charge up your bones, walk until you are empty and recharge them. This is like an electric car with a structural battery. A car needs a frame, replace the frame with a rechargeable frame.
So fundamentally, what do we mean by energy density? What’s the utility of that measurement? Well, we can use it to figure out how much fuel (in weight or in volune) we need to CARRY. Well, in the case of the structural battery, in a perfect world where 1 lb of steel structure can be replaced with 1 lb of battery, you don’t need to carry ANY fuel. So what is your ENERGY DENSITY CARRIED? 248 wh per zero kg. That’s an INFINITE energy density. That’s the first principles theoretical limit of a structural fuel source.
Now of course in the real world, you have to consider so so so much more. But you cannot ignore the benefit, the change created, from using a structural battery.
what about safety? is the 4680 safer to charge and discharge than 21700s? Cycles/lifespan? guessing there will be more specific information about these qualities in the future?
You got another cell for me?
I've been planning to try and DIY my own lithium cells at home using a 3d printed roller/consolidator, and have slowly been gathering materials, and learning as much as I can about their construction. I have no idea why I want to do this.
Its the curiousity in all of us.
Very good video
What about power density from a Supercharging point of view? Would these Texas vehicles already be able to sustain higher power for longer via a software update leveraging that majorly reduced resistance?
Already reported plenty of other places. Charge speed is the same as 2170
@@thelimitingfactor We need someone with ScanMyTesla or similar to do a charging video to see if Tesla is limiting charging performance to not Osbourne themselves or that's what they can do
Quite easy to notice by looking at the voltage profile and comparing 4680 vs 2170, maybe will only happen when Berlin pump them out and Bjorn get's one
And that also will answer the internal resistance question
How much does it cost to manufacture and what is the target production per yr for Tesla.
The correct question
All this technology but I am interested how long the battery lasts eg 8 years,10 yrs 12 yrs
Any chance Tesla is saving the better more expensive chemistry’s for cyber truck and semi since it will be more energy intensive to operate. While using cheaper more familiar chemistries to improve margins and keep specs consistent on model y to not hurt sales/make customers feel jaded? As it stands right now Tesla is still range/efficiency king so maybe it made more sense to focus on keeping range consistent but reducing price of manufacturing or atleast keeping it the same in attempts to battle inflation.
Nah, they went with tried an trusted to de-risk things
Well done presentation! What about difference in charging time between the 4680 & 2170?
Same. The 4680 pack charges at lower kW than the 2170 LR, but the time to full charge is the same. That is, smaller packs accept less kW.
ENERGY DENSITY VERY DIFFICULT TO COMPARE
Because of the structural purpose of these cells a Cell to cell comparison is not really relevant. Even pack to pack comparison is not relevant as there is also a differencein model Y body weights.
About the only way to properly compare would be comparing the weight of Tesla structural battery body-in-white frame with pack fitted, with a non-structural body-in-white frame with 2170 pack fitted. The weight used for the effective pack density of the structural battery would then be the (non-structural pack density) x (non-structural Kwh) + (difference in weight between the two fitted body-in-whites). Then divide by structural pack's kWh.
Yeah it's tricky
Hmm, I wonder in battery pack density calculations whether typically the packs are weighed wet (with coolant liquid). Using dry weights could be misleading if there is a difference in amount of coolant required between different pack designs.
And is dry or wet measuring consistent across brands. In testing it is amazing how a simple task turns out to be very complex when you think about it fully.
I believe Tesla is new to the cell game and it is very very difficult to handle higher Nickel based cells. From safety issues to degradation. These difficulties are the price you pay for more capacity of the cathode material.
🙌
4680 pack is the One million mile battery
Do you know what chemistry was used in the new 4680 cells?
I don't think they're nickel base.
NMC 811 - I showed it in the video
@@thelimitingfactor sorry I guess I missed it, but am I understanding correctly this is a (N)ickel(M)anganese (C)obalt mix? If so then something is not adding up.
On battery day, the battery was supposed to have a 16% increase in range while the entire manufacturing with the new Giga Casting was supposed to have a 54% increase in range? What happened, what am I not understanding?
I wonder what the density is for the Twitter battery? The positive and negative energy is never ending. Probably would last over a billion miles with one charge from an Elon Musk Tweet. If Tesla could only harness that think of the power. 😂
🤣
The more of these analyses I see, the more I'm encouraged to conclude that the 4680 has not delivered on its promises. Tesla seems to have gotten little out of this initiative beyond a somewhat more convenient form factor.
Correct on the former for the current state, incorrect on the latter. Cost cost cost.
@@thelimitingfactor ok, I’ll keep an eye on that. But, do we really have reliable cost data?
so if you take into account the cell can is heavier for the structural battery pack the the gravimetric energy density is about the same as the 2170 so why do you lead with the energy density is disappointing just dumb.
Calm your emotions, it's a battery
While you make a great point of R&D self-funding, it certainly wood be nice to see some of the cost reductions turned back to the customer. Elon keeps talking about EVs for the masses and saving the world. Right now these cars are only for the upper middle class and above. How long do we need to wait to see them for all? Personally, while I can see a day where we're talking about autonomous vehicles, that's a generation away IMO.
Demand exceed supply, so prices will continue to be high. Why sell a car for less if the customer will just turn around and sell it for more?
Great video and very nice to give the shout out to Matt Lacey. I am glad we can finally put all the mystery software locked theories to bed. It will be fun to see the 4680 architecture evolve over the years.
Amen!
@@hoppingrabbit9849 lol
it's better to lock by software than see battery fire happens in newspapers
Re: cobalt, Redwood Materials announced within the last couple days that 100% of the cobalt they’re going to supply to the new Panasonic factory in Kansas will be recycled cobalt. Not sure if it’ll be a significant percentage of the total cobalt needed, but still good to hear.
Jordan: excellent info; a minor nit: at 5:55 you mentioned the internal resistance - it should be 7 thousandths of an ohm, (7 milliohm) not 7 ohms.
Thank you for doing such comprehensive analysis and sharing it with us all!
Excellent work as always. I've been telling people from the beginning that it was unlikely there would be a future unlocked capacity upgrade for existing 4680 Model Y's, now I can point to definitive proof.
"Don't let the perfect be the enemy of the good"
Very important insight. It's about the utility to the user - and that utility includes a low price. It's also about the utility to the company - and that utility is a profit margin that allows investment in further optimization and research as well as rapid scaling.
Thank you so much for your work I'm looking forward to the next 4680 battery version 2. 😁
Me too! 🔥
While we would like to see all specs improve: less weight, more range, etc. It’s true that reliability and production rate is what matter most at the moment. Tesla doesn’t want to get millions of recalls in a few years on batteries or casting, that could destroy the company. It’s better to play it safe with the new technology until they have a lot of data on the failures modes.
Bingo!
100%... The combo of castings, structural battery packs and 4680s are all entirely new and so its imperative that Tesla play it safe. This will all get refined over time but lets take the changes out nice and slow so that there are no recalls. These components are clearly not designed to be replaceable and so they must get it right first time or the car is a writeoff. Lower efficiency right at the get-go is an acceptable tradeoff for me.
Yeah. The importance of range drops off after a certain point, maybe somewhere around 300-500km, when you simply *have* enough range for most of the things you'd want to do, from daily commutes to road trips.
Your average consumer also isn't going to care that much about how you get that range, whether it's a by increasing the size of the battery until you are left with a 2.5t hatchback or by optimizing the energy efficiency of everything you can get your hands on. Ultimately the only thing that matters once you cross that threshold in range, is reliability (for older/used vehicles with data on them), if the vehicle is even available for purchase and how much it's going to cost.
From your initial tear down of the 4680 the thickness of the cell walls looked like overkill. I'm thinking of a hollow door that is amazingly strong yet its center is an empty cardboard honeycomb. These cells are full, so less crushable and they are tightly packed together, doubling up the metal thickness where two cells touch. Then any void is filled with structural foam. Maybe they can reduce weight by making the cell walls a lot thinner without losing much of the strength. When you look at a modern soda can, it is paper thin but its shape and the content give it rigidity. I would think it would take the weight of a man. I'm suggesting there may be some wiggle room in the cell wall thickness is this something that could be tested in a computer?
Super happy someone has finally provided real world data. Thanks so much! Great video!
Professional and packed with details. I usually listen to my videos and double speed, but I had to slow down this video to take it all in. Keep up the good technical work!
🙌
Im not totally surprised that the Texas Y is heavier. One thing Ive been thinking is that the current Texas Model Ys will need to be as close structurally to other Model Ys as possible to maintain part commonality. This means that some of the structure of the rest of the vehicle is redundant to the pack because it has to exist for other versions and share common mounting points. I feel like we wont see a full optimization of the total structural design until all lines are using structural packs and everything is streamlined, or unless there is a whole new vehicle designed from the ground up to only use the structural pack and gigacastings.
I could be wrong, but It seems current 4680 ramp priorities are Now: More (production line speed), Cheaper (supply chain), and Later: Safer (electrolyte chemistry, cathode materials), Better (increased volumetric and gravimetric energy density, longer cycle life), Faster (higher charging rates).
Good summary
I like 'Safer' also, and wonder where that fits in the Tesla priorities schema. Does safer chemistry trump efficient mass/density? How much safer is the 4680 chemistry? Maybe it's a significant factor.
Safer could mean more life cycles as well?
Fantastic as always!! Cathode information is top of the list for me as well as it makes up over 50% of the battery! Manufacturability is key
Glad to hear it!
So Tesla's answer to competition is increased range by reducing weight and making manufacturing cheaper. And we should see those advantages in the next couple of years.
Thanks to Jordan, Munro, and the researchers at UCSD for providing this informative video!
Fabulous. as usual. We're spoiled.
🤗 JORDAN, THANKS AND THANKS TO SHIRLEY MENG ,WY KONG LEE AND ALL YOUR SUPPORTERS FOR MAKING THIS POSSIBLE 👍😎💚💚💚
👌 as always. The quality of your videos is wel appreciated
you have to compare the entire 4680 pack vs the entire 2170 pack for a fairer comparison because were not considering the impact of the structural design of the 4680 pack vs the 2170 pack. Im not sure what weighs more, the sum of the extra thickness of the 4680 cells or the weight of the added structural elements for the 2170 pack?
As soon as you buy me a pack, I'll do that, lol
@@thelimitingfactor haha
The big gain with 4860 vs 2170 is the price on the pack. Tesla make 8 batteries 4860 in the same time than 1,5 2170. And, on the batteries pack, you can remove (2976-828)×2=4296 welding points and, you remove 2976-828=2148 movements. This is the big gain now estimate 5.500$. Gen 2 and 3 will be better but, in next years but not now. 2170= 96×31 batteries and 4860= 92x9 batteries
Can thickness increase is also due to thermal propagation requirements. The higher energy of the 4680 also means that more energy would be released in case of thermal runaway etc. Therefore the thicker can thickness also provides more stability and helps to account for the higher energy content which could have the potential otherwise to ignite other cells in its vicinity
I think I need to make a video on this!
At 6:10 at the bottom I think you mean (3-5 mOhms), not just Ohms
Shit, nice catch
@@thelimitingfactor 🤣 Amazing video regardless
Wow Jordan ……….. simply wow.
😊
I had very high hopes for the 4680 cells. This initially seems disappointing. But when you factor in the knowledge that this is teslas first time manufacturing batteries, it’s actually pretty impressive that they’re able to get close to established battery manufacturers.
I take this as a good that they will eventually get there. But of course, other battery manufacturers aren’t going to sit still.
Tesla doesn’t have the battery advantage I thought they would. But, at least we can be sure they will not be subject to the bidding wars to come where battery makers charge exorbitant amounts as demand increases.
Tesla is thinking about basics and stays flexibel for other chemistries but could produce more affordable in big scale and have reserve in much better resistance/efficiency with thermal impact by fast charging - indepandent from chemistries - better structure thsn small cells [but LiFePo comes up with also better form and cooling] but flexibel in chemistry for faster charging and high density e.g. silicon/graphene/sulfur options. Step by step. O course Elon tells fairytail lines of the future but it needs time like all other stories. Imagine all goals come true and double the timeline - than it could be near at reality of products.
The high hopes come if you are new to batteries. I am sorry but there is unfortunately not a quantum leap in battery development. Battery is always a continous optimization. Trust me I work for one of the top 5 cell makers directly in Asia for 10 years. Made cells for all of the big OEMs.
Just a point on the can thickness,
Yes your loosing density at the cell level due to the thicker wall, but I think it's fair to say your gaining that density back in terms of weight savings in the finished product structural pack.
It's designed to operate as part of a system not as a individual component.
Theoretically yes, but we haven't seen that yet. In fact, the reverse. It will play out over time
@@thelimitingfactor do you have an accurate mass figure? Spoken reviews weighed his 4680 MY and found it to be 140lb lighter than a normal LR Y
Can thickness may also play a role in cooling IMO by helping transfer heat around to the cooling channel.
@@patreekotime4578 No, more thickness brings more thermal resistance of course with identical surface.
The most relevant channel on youtube and Tesla til date. Love your content and thanks for the dedicated videos. I am grateful
sometimes as a tesla investor, we expect too much. Tesla just achieved to build a world-class battery totally on their own, on par with the industry leading companies that have been doing batteries for decades. But many people see this as a disappointment. I guess I kind of understand, because of the things elon said at battery day.
Theyve literally already acheived 90% of the battery day announcements, and people are disappointed because they arent 100% there yesterday and already delivering on rumors. 🤣
@@patreekotime4578 They also fail to realise new things take time to mature, there are iterations to go yet. It's like the numpties who keep thinking a starship test article is somehow the final design.
I imagine that the tabless design will allow for longer cycle life vs a tabbed design cell for obvious reasons.
I also ENJOYED YOUR QUESTIONS WITH SANDY 🧐👏👏💚💚💚
Glad to hear it! I had so many more!
@@thelimitingfactor 🤗😎 NEXT TIME 👍💚💚💚
Just a guess, but wouldn't there be an upper limit to cathode thickness for a wet process due to the necessary evaporation of liquid from within the cathode layer? At the very least a thicker cell should increase drying time and make a wet process less efficient for thick layers
Oh boy, there are a lot of challenges, and evaporation is one of them! The interesting part is how to get around it...
Use different viscousities and different material mixes to create two layers at once. Otherwise you have to do multiple drying passes.
Realized or Unrealized 4680 battery, it's a great EV period...I have 3 Tesla: 2 MY LR and M3, sold my MBs in lieu of Tesla, not going back to ICE cars again....now my friends envy me...
Makes me wonder what Panasonic, LG and Samsung could achieve with a 4680 form factor, with regards to energy density? 🤔
LG and Samsung have already produced 4680 samples ... so they know already.
@@MrAdopado But it's the information out there? Do we know?
@@TheJAMF They are working hand in hand with Tesla so the thing we do know is that if they make a significant development it will benefit both sides.
Rather disappointing...
What would really bring down costs is increasing energy density. You triple the energy density, you need a third as much batteries, 66% cost reduction right there. Also less weight, less volume.
So Tesla reduces weight due to the structural battery pack. However they have to make the cans thicker. So they get there 10% extra weight for the batteries. For a 70kwh battery that is .1*70000/269=26 kg. That is not too bad. I wander how much weight Tesla plans to reduce on the long run on the structural pack.
So, out of all breathless announcements during the last Battery day, only cost reduction was real. (FWIW, I expected greater internal resistance reduction from tabless design; obviously, I don't know enough about the topic.)
...so far 😉
as an tesla investor i spend my life thinking, hmmm, if i had a pound for every time i hear the phrase ''yeh but, but, in the future''
I dont understand how peoples expectations for the first mass produced 4680s were that they would magically beat the industry leaders right out of the gate. One of the major points of battery day is that they showed the potential once they leverage ALL of the different strategies they are working on, but that those strategies were not all coming together at once. As we already knew that most of the chemistry-related improvements werent happening yet, expectations should have been somewhat tempered IMO. And really, honestly, if they didnt make any other improvements, if they stopped working on R&D today, just beating the competition on price is enough.
I am a cell design engineer. The cross-section image of cathode electrode greatly confuse me. The thickness of 4680 is 180 micro meter for double layer? but I cann"t see aluminum foil. If it is one side thickness? It is 2-3 times of the common used design. Hope your reply.
Due to the way that the electrode was cut, it's difficult to see the foil.
So yes, what you're seeing is active material/foil/active material
Got it. Sometimes in the CP image foil can be seen. Thanks!
I love your video very much and I learned many things from them. I read many papers introduced in your video. Thank for that. I have several years of experience for EV cell design and manufacture. Hope and glad to do something for your video if necessary.
I disagree with your assessment of the can thickness. The cell is a pressure vessel. Pressure vessels with larger diameters need a thicker wall to hold the same pressure. The “hoop stress” is equal to Pressure * Radius / wall thickness
10.5/0.25 = 42
23/0.55 = 42
The 4680 has identical pressure capability to the 2170. And the 4680 packaging should still be a lower percentage of the cell mass compared to 2170.
Yeah, it would take a whole video to go through that. You're partially correct. People always oversimplify batteries because they see one piece of the elephant.
oof.
This will be a great episode!
They didn't get their projected power density, so they have to cut weight to get their planned vehicle performance.
Does the heat sinking capability of the Tabless Electrodes give the 4680 battery a serious advantage over the Panasonic 2170 and the 5 tab Panasonic 4680 cell?
See the 4680 Thermal Design video.
How does the Cycle/Shelf-life on these batteries compare?
Maybe there will be battery day 2 ? Once 4680 is ramped and meets / exceeds battery day 1 specs.
I hope so!
Nice! 1:47 420 miles on it
I think the biggest question is how many cycles does it have... that's what matters most if you have a battery that last 1 million miles then you no longer have to worrie about hurting battery and have peace of mind your not going to need to replace battery once you finish paying for the car
Are other manufacturers using 5-tab instead of tabless because of Tesla patents?
Five tab design is a lot easier. From memory, the patent application for the tablets electrode wasn't strong.
So I think there's wiggle room there for other people to do it
Tesla has released its patents (subject to certain conditions).
@@fredbloggs5902 Right but my understanding is that the conditions are that the other company allow Tesla to use their parents too and I'm not sure whether other companies are open to that.
Great video! I’m thinking of buying a model Y within the coming years and the battery day presentation has been in the back of my mind all the time thinking that Ím going to wait for the new version before buying one. Really nice to finally hear someone talking about all the aspects of the new platsform and link it to the battery day presentation!! I know you have limited knowledge about the exact future of tesla around when we can expect to see the full pontential of battery day and such but the I depth review of the current battery cells is very awesome to get. So thank you!!
There is always going to be a newer better faster version just around the corner.
I was in the same mindset on Battery day. I decided to go for a MYP and took delivery in February 2022, and settled for a Freemont build. I already put 13k miles and since I have solar I paid 0 electricity, and 0 maintenance or repairs, knock on wood. It only consumed about 3800kwh which for a 3.5s 0-60 car seems unreal. Had a MB previously and this is the best car I ever own. I figured I will keep it until the cybertruck is readily available at a decent price, which will definitely take a while.
🤗 LOOKING 👀 FORWARD TO YOUR NEXT VIDEOS 👍💚💚💚
Great work. So the work cut out for Tesla to improve. The path they took hopefully gives more scope for improvements.
I am waiting for 400Wh/KG. We will fly...
nice. pretty much the conclusion on the 4680. Turns out that the reason the why the AWD vs LR weighs the same but different capacity/range is because of Panasonic's use of silicon. Weren't for that, the max range or battery capacity would be the same for both.
244wh/kg for Tesla's 4680 is disappointing. They need 310+Wh/kg or 110Wh/cell to compete with CATL Qilin in the future. Tesla is way behind and can't even ramp it up. They are already behind schedule by 1 year. Tesla please do something. But i guess Elon is to busy managing Twitter. lol
Incorrect. Video coming out next week.
👍👍
Terrific job. ETA on next video?
For Patreon supporters, 9 days 😉
11:00 The "power" factor likely has more to do with the upcoming Tesla Semi truck and Cybertruck than it does with the Gen 2 Roadster and current Plaid lineups since high, steady torque from high, steady power is required when towing large loads up hills and mountain ranges during long-hauls. Though there are no immediate plans to use the 4680 in the initial Tesla Semi truck targeting intra-city consumer goods distribution, it will likely be the go-to battery for all Tesla platforms, including Powerwalls and Megapacks, once economies of scale drive down cost ... right about the time when interstate long-haul shippers will start getting their Tesla Semi trucks.
Nah, the larger pack allows for more power. Pack will be 9x larger than the Model S, but only twice the motors and they'll be smaller motors.
I really like the video and the work, but the energy density figures are a bit underwhelming.
This means this has inferior energy density to the LG M58T by a decent margin, rather than being to close to on par.
To be fair though, structural designs do provide a large amount of benefit, and the chemistry differences do make a large difference.
Finally, another thing that does actually dissapoint me is how high the power losses are for the cell.
Getting 90% of your rated capacity at 1C discharge rates is honestly quite poor when considering cells like the Molicel P45B do far better.
That's because the Molicel is a high power cell rather than an energy cell (note that it has lower energy density)
Besides, you really need to test the cell rather than go off the marketing material, and test it on the same rig in the same conditions.
Beyond that, on power, it depends on whether you're talking 30 second peak power or full discharge. Those are different situations that are dependent on different variables.
Interested to see the video comparing the blade cells, LFP is still the chemistry that makes the most sense to me atm especially as they improve energy densities using it.
Is the gravimetric energy density that important?
In an airplane, battery weight is critical. In the car, a high volumetric energy density or a high energy density per base area is important in order to be able to install as much cell volume as possible with a limited wheelbase. 80 mm high cells allow more volume in the battery pack than the 70 mm high cells. BMW even plans 95 - 120 mm high cells. These higher cells have even lower kWh costs.
What Tesla plans above the 4680 is not yet known. Tesla doesn't need to admit that either.
It also serves a proxy just fine for volumetric.
Was that an intentional mileage listed, continuing Elon's jokes about 420. Or is there some kind of cosmic fate event happening.
Cosmic fate, lol
For the structural battery comparison to non structural battery you would have to include the structure in both cases obviously. So basically the 4680+floor of car VS other + floor of car.
Yeah, there's wiggle room in a few different directions on the energy density figure.
Thank you!
This is pretty sketchy. I'd like to see a new-to-new battery capacity comparison.
Well get to it then! 🤣 Go get a fresh 4680 from Fremont and likewise from Nevada and put them through their paces.
Be sure to share the results with us.
100% some other companies will also go "tabless". I can confirm it.
🔥🔥🔥
From my undersyanding with the design of the tabless electrode and surface area advantage i cant see why they are not 46 x 120mm or even longer.If it could be double the length in an 65mm can i think production speed could be halved for energy output! I know they have done their calculations but now being 3 years along since initial announcement i cant help feel in hindsight that they could have made the cell bigger and therefore stronger as well in respect to more rigid as being longer would make it far more rigid ! Anybody got any thiughts on this?
Packing density starts reducing at larger cylinder sizes. I didn't believe it, then I saw it modeled.
@@thelimitingfactor but still the longer the canoe the more stable it is . Does that analogy ever hold water! 😂
Outstanding work. Thank you.
So - the benefits of the 4680 mostly accrue to Tesla Investors *today* and to the driver over the next few years.
🔥🔥🔥
Some may think that the cell content (the "jelly roll") should take some of the forces exerted on the can. They reason that the content could increase the can's rigidity. Stresses on the "jelly roll" could cause cracking and other defects of the "jelly roll"; so, not a good idea.
Correct!
So no real evolution in the last 13 years.
Where is the UCSD source link, I am really interested.
I am the source. I worked directly with them and published it on my channel.
Great content as always. Thank u Jordan.
Tesla's 4680 cells are a huge disappointment, to say the least. GM's Ultium batteries have 272Wh/Kg, today, and GM is looking to release a solid-state battery with partners, that has twice the capacity of their Ultium NMCA batteries, in 2-3 years. Tesla will fall way behind as they cling to a dud battery.
Faulty logic. Tesla is using the same 272Wh/kg batteries in China Modely Ys. Yet, they're switching to the 4680. Why? Cost and scalability and long term options for energy density improvements.
Edit: Also, solid state is bunk for now. There are already solid state batteries in vehicles and they perform the same as liquid electrolyte batteries. But, they cost a lot more.
Havnt seen anyone tear down a Hummer yet to confirm that.... Lol.
i will now reveal who you really are under that beerd .. dendritesz ... all water leaves residue ... the cleaner the water the less the dendritesz
not that batteriesz matter ... go put a hole in your boat or generate form your own motor now and use batteries to buffer
Great video as always!