dude, this was a great explanation. It was super detailed and yet done with a fantastically accessible approach. Thanks so much man.

I understood the "jelly roll" but the tabless concept escapes me. Until you showed that toilet paper with those post-ts and then it dawned on me. Awesome! Good analog!

I’ve noticed obvious things are generally only obvious after the fact.

In the calculation of the internal resistance of a foil, the tabbed design was for a conductor 80 mm wide and 800 mm long, for the tab-less foil it was 80 mm long and 80 mm wide. (Website flashing by at 15:14) Shouldn't the width be 800 mm in the second case. This would make the internal resistance two magnitudes lower, not just one. Now, in real batteries the internal resistance is also affected by the resistance in the electrolyte and polarization of the electrode so it isn't as easy as just calculating the loss in the electrode material.

I'd argue that 90% of innovation is someone saying "why don't we just do it this way?" and everyone else just replies "duh, why didn't we think of that."

It's good that you are self-employed. Imagine your boss looking over your shoulder while affixing Post-It notes to TP. "Hey Dave, whatcha doin'?"

It never ceases to amaze me your knowledge im surprised the new Dave battery patent isn't already out there cheers

Long videos, but the only channel I can rely on to get consistently accurate and well-informed explanations about the latest in the tech world

The thing is that they were able to scale the cell size without compromising, charging speed, power, and heat rejection. Pretty good in my book.

Thank you Dave, you always teach us something.

Very well explained, I was curious about this. Thank you

Dave as usually, giving the best possible explanation!

love the way Dave just gets carried away and bombarded us with tons of information.

Wow, thank you Dave. Appreciate your contributions.

I like how you're passionate about the topics you talk about! This has been enjoyable

Someone said at the Factory "This isn`t a Capacitor, this is a Battery".

Imagine if they all had batterisers installed.

Longer and thicker is better... obviously 😂😂

Really helpful gave a lot of knowledge and cleared all my doubts about the most confusing battery tech

Very interesting and extremely well explained. Thanks Dave!

I finaly understand tabless design, it was so confusing before, thanks for the explanation.

It's hard to overstate how much Dave makes the world a better place with his videos. Sincere thanks.

Beautifully explained Dave. Its amazing how such a simple rethink of cell design to remove the tabs can resolve so many limitations of the previous cell generations. Very excited to see where these advantages, especially in manufacturing costs, bring the final cost of cells. I just may have to build my own powerwall some day!

Great presentation! Easy to understand. Thanks!

incredibly good explanation as always thank you Dave

Remember Dave, maximum packing density if circles/cylinders are always the same regardless of diameter. The tabless design allows for the removal of the cooling pipes between cells regardless of cell dimensions, so that density improvement isn't attributable to cell dimensions. It can however reduce the energy density with cell dimensions if there is less cell can and wiggle room needed for inserting the jelly roll.

Great educational video! Really appreciate the efforts!

Extremely nice and Simplified explanation, big thanks for this one! ;D

The tabless design is a good example of something that seems obvious once you see it

“Why hasn’t this been done before?” My guess: 1. Tradition (the “aye bin” approach if you’re Scottish). Batteries have always been made this way, so we won’t think about alternatives. 2. Existing companies don’t want to invest huge amounts in developing new methods to produce cells with cap ends. They’re already making a good deal of their old production line which has been going for a decade, they’re not about to pay someone to develop this, create machines to do it then halt production of their existing ones to retrofit in new ones. Tesla has the massive advantage of being a new-to-market (being battery market in this case) company and thus being able to look over their production top to bottom as they set up instead of retroactively. Plus Elon’s the kind of whacko who will throw money and time at this to make it perfect instead of settling for less. Just the sort of whacko we need right now.

great presentation, Dave!

The best explanation, good job. Thanks so much!

what a wonderful presentation! Thanks for taking the time to make something like this! Interested in Tesla's battery day technology!

When you have cuts in a strip of material that is tensioned to be rolled up into a cylinder, you risk tearing it up and disrupting your high speed production line. They must have found a clever way to avoid this. Perhaps cutting the tabs as late as possible in the process.

@EEVblog THANKS Dave!!! Your a beaut m8, can always rely on you for solid info and functional explanations.

excellent tutorial...many thanks ...sid

Please be reminded that 1) Conventional tab (have preload force) to secure contact resistance also spark proof. 2) Tab less / multi tab architecture have more tabs made of annealed soft copper to be in touch with casing (without a preload force) have undefined contact resistance. Tabs will deform under mechanical shock on road. It cannot reform itself once deformed. Gradually the effective (passing current) tab counts continues to drop as shock persists. When the last effective tab remains in the circuit the next shock will open circuit at that tab-case junction producing a spark next to hot chemical inside to a possible internal ignition/combustion.

"Marketing Wankology" should be a class

well done; I learned all i need to know about these new cells right here from your video. :)

EXCELLENT DISCOURSE

great review on the new TESLA 4680 cell design - so far the best I've watched! thanks Dave!

Many great inventions/solutions look obvious when found; it’s just a new way of looking at the problem that leads to the breakthrough. I love the elegance of these kind of solutions!

I was searching for a video about these new batteries that would explain why they are better and this is easy to understand! Thanks so much!

Excellent explanation Dave - thanks!

46 x 80mm is the EXACT dimension of a dunny roll. Now I know who was hoarding all of that toilet paper at the start of the pandemic.

So happy I found you many years ago. Most valuable channel on KZfaq for me coming up as an engineer.

incredible explanation

Thanks for the tutorial.

Battery Engineer: So we need more tabs to get better current flow... how many do we need? Tesla: Yes!

The continuous tabs trick is pretty simple and obvious, I remember thinking about that years ago. My question is: why it wasn't done before? I mean, in comparison with the amount of knowledge and research in chemistry, this is nothing and improve noticably. Or just several tabs at least (was it already done in high C-rate cells?)

Awesome content - Bravo ! makes it so easy to understand.

Great explanation

This guy's vibe is so great he could be giving you your cancer diagnosis and you would laugh

This really shows how important it is to thoroughly examine assumptions. There is a story about a newlywed couple where one of them makes a roast and cuts off the ends before they start and the other asks why. This is the way my parents did it. When the parents are asked the reason was "the pan was too short". Doing things the same old way is a liability especially today when Every think is changing from week to week.

Oh wow... That was well explained. Thank you!

Very good explanation! Kind regard from Austria.

"i'd expect more than 16%" ... Watch battery day again. They state explicitly that the 5x power, 6x range, 16% range is due Only to the form factor. Then they walk through all the other advances and add in their effects, ending up with a 54% increase in range overall.

Good instructive video,Dave. It goes to show how newer generations of engineers sometimes suffer a sort of collective amnesia. The tabless roll design was invented decades ago with film capacitors for the same reasons.

Very well explained.

Wonderful explanation! 💪🧠

So would the cathode side be the same extended, cut, and folded sheet, just with aluminum?

Nice deep dive, Dave. The tabless construction allowing for both a decrease in ESR and in thermal resistance is huge. The only think that was missing was actual Amp-Hour numbers (or estimates of same)

Great work very informative ,i always listen to you if i want to know what's really going on in the wide world of electronics , thank you.

Great video. Explained it very well.

Great intro as always, Dave. I think the single tab leads on those plates initially did not make anybody concerned much as historically capacitors have been wound like that for decades. In fact, I have seen capacitors where the tabs were shaped from the plates directly, eliminating the need to weld contact terminals to the capacitor plates. This however became more of an issue with batteries where energy both in quantity and induration is far greater as opposed to capacitors, which also can get warm if their power handling is high.

What a great teacher you are!!! Don't forget these new batteries will be sandwiched into a pack which will be like a hollow door which only have a cardboard honeycomb inside but are amazingly strong and rigid, hard to twist, so the batteries become a structural element of the car.

dave, thanks for the video, really like the detail. keep it up.

Love your direct approach, this is how it works and really just comes down to size increase. Heat dissipation is better, but again size. Thanks for sharing.

26:28 isn't the packing efficiency for cilindres independent from its diameter? 16% is pretty impressive to be honest, its a high optimized product already

In large part, the original cell were designed for small cell counts, computers, in particular, also tools so the tabs acted as a Fuse to protect the user from failure

Thanks EEVBlog. I'm a battery engineer and I got a lot of help.

Well done!

Max packing density of identical circles is 0.9069, this is independent of diameter. The big savings of larger diameter is much less casing material and decrease in total plant number of operations, since you are processing fewer cells. And volumetric energy density isn't such a massive issue anyway (everybody drives an SUV), the real issue that matters for EVs is energy per unit mass. kWh/dm3 is def an issue, but not as high of a priority as kWh/kg. I think the reason they stick with cylindrical cell design is for increasing speed of production. Both prismatic and cylindrical cells are wound around a mandrel and winding speed per unit length is probably not hugely different, but with cylindrical cells you can use continuous motion assembly equipment to do all the further processes (like what you see in bottling plants with insane throughputs). This would definitely be a necessity if they plan to deliver their 2TWh/y or whatever musk's stated ambition is. Inb4 accused of being fan boy. I just think that if they're sticking with the cylinder design there is probably a very good reason. In the past that company has been very quick to kill their babies and abandon designs that didn't work, so I would expect them to do the same with the cylinder v prism design.

"4 times the size. 16 times the detail!"

Very informative, great video!

Great video 🙌🏻

Great vid, there is an entire recycling system as part of the battery technology development as well, so that makes the solution irresistible. Also, thermal paste between end cap and folded copper would be very efficient... unless chemical reaction, but im sure that could be resolved. Wonder how this transforms drone tech. And portable tools...

Yeah with the larger cell you save about 16% weight in steel and replace that with cell. They didn't increase the energy density per cell just increased the thermal conductivity and electrical conductivity. Yes it is an order of magnitude, and that will result in less waste heat but still, the energy density of lithium is not changed with the cell design just efficiency.

Great explanation!

It's actually your best asset, standing in front of the whiteboard and teaching us all. Much of the other stuff can be quite repetitive in terms of the wordings used. (...aficionados playing along at home.....etc) This was a joy. Cheerioh

When its circled with a box you know its important

I'm here after listening to Clive Mitchell's thoughts on the topic (and hearing about these new cells from him as well), so I'm excited like an electron!

The best video explaining 4680 battery.

So good explanation. I learned a lot:)

Bigclive did a video correctly predicting that this was probably the "innovation" behind Tesla announcement. Nice technique anyway

Why nobody else thought of it: Its hard until someone figures out how, then it's easy.

Best review of Tesla Battery Day I've seen! Great explanation!

great video...thanks!

Would be nice to see how they handle the cathode - everyone talks about the anode, but I haven't seen anyone mention what they intend to do with the cathode.

On the subject of "folding tabs" being used along the length of the anode material (instead of single tabs)... Do you think a similar improvement could be made to electrolytic capacitors to improve their efficiency and speed of charge/discharge? I believe that all electrolytic caps use the single tab at the ends approach.

Excellent explanation. Thanks, Dave! Like you said, it's a win all-around. Congrats to the Tesla engineers!

Awesome video. Thanx.

Capacitor manufacturers will be able to produce super-low ESR caps like this!

lol 11:58 "Please excuse the crudity of this model. I didn't have time to build it to scale or paint it" back to the future line

great video Dave, I liked your explanation, and demo.

Thank you for this information as an electrician you gave me the inside info and I could follow this easy, Lotta Love

1:17 - I think that the ‘0’ in 18650 denotes a cylindrical cell rather than a decimal point.

They said that the +16% was strictly due to the size of the cell. So that was expected.

Great presentation. Clarified how 'Tabless' was achieved, and its implications for thermal and power management. Many thanks.

VERY VERY INFORMATIVE VIDEO!!! LOOOVED IT!!! THANKYOU.