Should you know what's inside those 4680 battery cells Tesla is putting inside its cars? Tesla doesn't think so, and that's a problem.Tesla and Elon Musk have been singing the praises of 4680 battery cells for almost two years. The world of electric cars is all atwitter — you should pardon the expression — about this wondrous new battery technology. But what exactly is the story here? In a blog post on Medium, Will Lockett asks some probing questions and comes up with some disturbing answers.
“In September 2020, Musk revealed to the market Tesla’s 4680 battery and, at face value, it looked like it would revolutionize the EV world. It promised to slash the cost per kWh by 56%, produce more power than its predecessor, come in a structural pack (increasing the crash safety of the car), be more resilient to supply chain issues, be better for the environment, and even charge quicker. With such a battery, Tesla could finally offer their $25,000 EV, paving the way for the Cybertruck and second-generation Roadster to become a reality. Two years down the road, Tesla is only just starting to put 4680 packs into its cars, but recent teardowns have shown that something fishy is going on, as it seems Tesla might be pulling the wool over our eyes.”
Lockett says the 4680 has several unique and groundbreaking features. Its larger size — 46 mm in diameter by 80 mm long — allows each battery pack to use fewer individual cells, each with a higher capacity than a traditional 2170 cell. That makes the production and assembly costs of the battery pack lower. Instead of being bolted in the way they are in a traditional battery pack, they are set in a resin brick, which allows the pack to become a structural member of the car. This also lowers manufacturing costs.
The 4680 battery also reportedly had some significant internal changes. Rather than a graphite anode, it was supposed to use a silicon anode. That should make the 4680 far more energy dense and able to charge and discharge at much faster rates. Rather than using the typical NMC 811 (80% nickel, 10% manganese, and 10% cobalt) cathode, the 4680 was supposed to use a cobalt-free, high-manganese, low-nickel cathode. The cathode and anode are also said to be dry coated, which speeds up production and further reduces costs.
Finally, Lockett writes, rather than having a small tab connecting the anode and cathode to the positive and negative terminals of the battery, the 4680 has a strip of metal on each end of the rolled up battery that is folded down after rolling to make a flat plate-like metal surface that connects to the terminals. This makes manufacturing cheaper by having fewer assembly steps and reduces the power bottleneck in the terminals, making ultra-fast charging and high-power outputs possible.
Houston, we have a problem. Lockett points out that independent analysts like Sandy Munro have found that the 4680 battery cells being used today in some Tesla cars contain almost none of the groundbreaking features Musk hyped up back in 2020. They are 46 mm in diameter and 80 mm long and they are tabless. “But everything else is missing,” Lockett says. Here’s more:
“These teardowns showed that the anode material is graphite and the cathode material is NMC 811, meaning its internal chemistry is identical to its older 2170 cell. This means no superior charging speeds or higher energy density. It also means that this cell is still making use of environmentally damaging and humanitarian-troubling cobalt mining and remains vulnerable to nickel price rises. To make matters worse, the cell walls are three times thicker than a 2170 cell, further driving down energy density.
“It is very hard to identify whether the electrode is dry coated or not, as both methods of coating do the same job, and the results look identical. But this method is the thing causing Tesla to struggle to ramp up production because it is a bottleneck. Each time they try to produce more cells, the quality of the dry coating drops, and only a few cells pass quality control, causing the cost per cell to rise dramatically. But if they can nail this tech, the cost per cell will plummet massively. It stands to reason that if the current 4680 cells were dry coated, Tesla would be making a big deal of it. So, in all likelihood, the current 4680 cells probably aren’t dry coated.
“Far from being a groundbreaking, industry-shaking battery, it seems the present 4680 is just a bulky version of the batteries we already have.”
There Are 4680 Cost Advantages
Even without all the benefits promised, the 4680 battery cells do lower costs of manufacturing, Lockett says. “A 4680 pack for a Model Y costs Tesla $7,400, which is 33% cheaper than the equivalent 2170 pack. Yet, this is still a way off the target of 56% cheaper and without any upgrades in terms of energy density, range, performance, or charge speeds.” Then he gets to the meat of his argument.
“I, along with many other people, have thought that, at the very least, the current 4680 is more than just a larger cell. Tesla has been very sneaky by not being open about the nature of these 4680 cells. It almost feels like their silence is a tactic to make people think they are buying a car with a next-gen battery in it. When in reality, they aren’t.
“But should we really be annoyed at Tesla for this? After all, things like silicon anodes, dry-coated electrodes, and cobalt-free cathodes are all on the bleeding edge of technology. Can we really expect Tesla to pack all of this into a battery and then produce it on a large scale at dirt cheap prices?
“No, we shouldn’t. It makes sense for Musk to incrementally introduce these aspects into the battery production line. Start with the easy parts like the form factor, tabless design, and structural battery pack. Then start introducing the unique internal chemistry and finally start dry-coating. This way, each of these aspects’ production methods can be developed and refined before moving on to the next. Therefore, you create a robust, reliable, and efficient production line as quickly as possible.
“What isn’t okay is the silence over what is actually happening with the 4680 development and production. The fact that these teardowns have unveiled this rather than Tesla themselves announcing how 4680 development and production is going is shameful. It leads to many thinking they are buying something that they aren’t. Moreover, this adds to the growing notion that Tesla is, behind the scenes, rather a shady and morally ambiguous company.”
Ouch! A shady and morally ambiguous company? That is a powerful indictment. But wait. There’s more.
“So yes, something fishy is happening at Tesla, and the incredible 4680 battery is still in production hell. I would be looking to get my act together if I were Musk. It isn’t just Tesla in the EV game anymore. Even if Tesla finally gets around to making a 4680 with all the promised specs, companies like CATL, ONE, and Quantumscape are all producing open-market batteries that have the potential to not only match but blow the 4680 out of the water. Any more delays and Tesla will start looking antiquated.
“The rose tinted glasses are also starting to slip. The public is becoming more aware of how Tesla treats its workforce, how they approach the right to repair, and now how questionable their PR is. If Tesla continues this way, it won’t be the golden boy of the EV world for much longer.”
The Takeaway
I am not a battery scientist nor have I ever played one on TV. But when the 4680 news first surfaced, nobody knew much about what was inside and Tesla was pretty quiet about technical details. Tesla has shut down its media relations office and does not respond to any questions from the press. The only news we get about the company comes from Elon’s tweets, quarterly conference calls for shareholders, and special events like AI Day.
It’s a situation that invites commentators like Will Lockett to see skulduggery and malfeasance everywhere. It’s one of those unforced errors that seems to result from Elon Musk’s dictatorial leadership style.
Are people entitled to know specifics about the batteries that power their electric cars? That doesn’t seem unreasonable. Tesla does itself no favors by its obstinacy. Transparency isn’t hard. In fact, it’s smart business. Elon’s insistence on lowering a cone of silence around his business interests creates self-inflicted wounds. He should know better.
Featured image courtesy of Panasonic.
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