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Tesla 4680 cells compared with BYD Blade and CATL Qilin structural batteries
The battle for the dominance of the electric vehicle sector would likely be determined by the market’s key battery makers. With this in mind, companies such as BYD, CATL, and Tesla — all of whom are exploring the structural battery form factor — have the chance to become the trailblazers of the next generation of electric car batteries.
During its Battery Day event, Tesla announced its 4680 cells, which are used alongside the company’s structural battery pack. BYD, on the other hand, has also released its Blade batteries, which also adopt a non-modular approach. CATL’s Qilin batteries are in the same segment, with its structural battery design.
Electric vehicle battery enthusiast Jordan Giesige of YouTube’s The Limiting Factor channel recently conducted a comparison of the advantages and disadvantages of Tesla, BYD, and CATL’s next-generation structural packs. Each battery pack was evaluated according to several factors, such as design, rigidity, packing and energy density, and safety, before being ranked. It should be noted that the figures used in the comparisons are drawn from estimates and materials released by Tesla, BYD, and CATL themselves, not current real-world observations.
As noted by Giesige, Tesla’s 4680 structural battery packs utilize hundreds of cylindrical cells with a cooling ribbon in between every other row of cells. A lid is then placed on top and polyurethane foam is injected into the pack. This polyurethane hardens, and the combination of the foam and the battery cells forms a rigid, honeycomb-type structure.
CATL Qilin batteries, which could be fitted with both nickel and iron-based cells, integrate thermal pads, the liquid cooling plate, and the cross bracing to create what could be described as structural cooling. The structural cooling is placed between each row of prismatic battery cells, and the cells themselves are placed into the pack directly without any modules. BYD Blade batteries use iron-based prismatic cells, though these cells are longer and thinner than those used by CATL. The cells are then stretched across the BYD Blade battery pack, allowing the cells themselves to replace conventional steel beams.
In the rankings of the next-generation batteries, the YouTube host noted that Tesla’s 4680 structural battery pack would likely be the most rigid among its peers. Tesla’s 4680 pack loses out in terms of packing density, however, as BYD and CATL’s use of prismatic cells maximizes volumetric energy density. With this in mind, and considering that CATL’s Qilin batteries can be fitted with high-energy density nickel-based cells, a nickel-based Qilin battery would likely be more energy dense than a nickel-based Tesla 4680 pack or a BYD Blade structural battery, which uses less energy dense iron-based cells.
As for cooling, Giesige noted that the BYD Blade batteries’ plate cooling would likely fall short of the Tesla 4680 pack and CATL Qilin battery’s cooling systems. In its marketing materials, CATL highlighted that cooling the sides of the Qilin battery increases the pack’s cooling area four times. Tesla’s 4680 battery also uses better cooling than BYD’s Blade batteries with its side cooling system, though it would likely not be as good as the cooling of CATL’s Qilin structural packs.
While BYD’s Blade batteries lose out in cooling, they are also likely the safest among its peers. This is because the BYD Blade battery uses iron-based cells, which have a higher decomposition and lower heat release temperature than the nickel-based cells used in Tesla’s 4680 cells and CATL’s nickel-based Qilin batteries. An iron-based Qilin battery comes second to the BYD Blade, partly due to its use of shorter and thicker prismatic cells, which may trap more heat.
A Qilin pack with nickel-based cells was ranked last in terms of safety by the battery enthusiast, as Tesla’s 4680 pack with nickel-based cells features several safety systems, such as an overpressure mechanism on the bottom of the cells themselves. Since 4680 cells are also smaller than the prismatic cells used in the BYD Blade and CATL Qilin, they contain less energy. The 4680 cells themselves are enclosed in a thick shell as well, which are about 2-3 times thicker than a conventional battery.
Overall, Giesige noted that Tesla’s 4680 cells are likely the best all-rounder compared to its peers in the structural battery segment. The overall scores of the BYD Blade and CATL Qilin batteries bode well for Tesla’s future, however, as the companies could become suppliers of the EV maker in the future. CATL is already supplying Tesla with LFP batteries today, and BYD is heavily rumored to be a Tesla supplier as well. In a way, the analysis of the next-generation structural EV batteries shows that Tesla is not alone in pushing the battery industry forward.
Watch The Limiting Factor‘s full analysis in the video below.
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Tesla confirms that it finally solved its 4680 battery’s dry cathode process
The suggests the company has finally resolved one of the most challenging aspects of its next-generation battery cells.
Tesla has confirmed that it is now producing both the anode and cathode of its 4680 battery cells using a dry-electrode process, marking a key breakthrough in a technology the company has been working to industrialize for years.
The update, disclosed in Tesla’s Q4 and FY 2025 update letter, suggests the company has finally resolved one of the most challenging aspects of its next-generation battery cells.
Dry cathode 4680 cells
In its Q4 and FY 2025 update letter, Tesla stated that it is now producing 4680 cells whose anode and cathode were produced during the dry electrode process. The confirmation addresses long-standing questions around whether Tesla could bring its dry cathode process into sustained production.
The disclosure was highlighted on X by Bonne Eggleston, Tesla’s Vice President of 4680 batteries, who wrote that “both electrodes use our dry process.”
Tesla first introduced the dry-electrode concept during its Battery Day presentation in 2020, pitching it as a way to simplify production, reduce factory footprint, lower costs, and improve energy density. While Tesla has been producing 4680 cells for some time, the company had previously relied on more conventional approaches for parts of the process, leading to questions about whether a full dry-electrode process could even be achieved.
4680 packs for Model Y
Tesla also revealed in its Q4 and FY 2025 Update Letter that it has begun producing battery packs for certain Model Y vehicles using its in-house 4680 cells. As per Tesla:
“We have begun to produce battery packs for certain Model Ys with our 4680 cells, unlocking an additional vector of supply to help navigate increasingly complex supply chain challenges caused by trade barriers and tariff risks.”
The timing is notable. With Tesla preparing to wind down Model S and Model X production, the Model Y and Model 3 are expected to account for an even larger share of the company’s vehicle output. Ensuring that the Model Y can be equipped with domestically produced 4680 battery packs gives Tesla greater flexibility to maintain production volumes in the United States, even as global battery supply chains face increasing complexity.
Elon Musk
Tesla Giga Texas to feature massive Optimus V4 production line
This suggests that while the first Optimus line will be set up in the Fremont Factory, the real ramp of Optimus’ production will happen in Giga Texas.
Tesla will build Optimus 4 in Giga Texas, and its production line will be massive. This was, at least, as per recent comments by CEO Elon Musk on social media platform X.
Optimus 4 production
In response to a post on X which expressed surprise that Optimus will be produced in California, Musk stated that “Optimus 4 will be built in Texas at much higher volume.” This suggests that while the first Optimus line will be set up in the Fremont Factory, and while the line itself will be capable of producing 1 million humanoid robots per year, the real ramp of Optimus’ production will happen in Giga Texas.
This was not the first time that Elon Musk shared his plans for Optimus’ production at Gigafactory Texas. During the 2025 Annual Shareholder Meeting, he stated that Giga Texas’ Optimus line will produce 10 million units of the humanoid robot per year. He did not, however, state at the time that Giga Texas would produce Optimus V4.
“So we’re going to launch on the fastest production ramp of any product of any large complex manufactured product ever, starting with building a one-million-unit production line in Fremont. And that’s Line one. And then a ten million unit per year production line here,” Musk stated.
How big Optimus could become
During Tesla’s Q4 and FY 2025 earnings call, Musk offered additional context on the potential of Optimus. While he stated that the ramp of Optimus’ production will be deliberate at first, the humanoid robot itself will have the potential to change the world.
“Optimus really will be a general-purpose robot that can learn by observing human behavior. You can demonstrate a task or verbally describe a task or show it a task. Even show it a video, it will be able to do that task. It’s going to be a very capable robot. I think long-term Optimus will have a very significant impact on the US GDP.
“It will actually move the needle on US GDP significantly. In conclusion, there are still many who doubt our ambitions for creating amazing abundance. We are confident it can be done, and we are making the right moves technologically to ensure that it does. Tesla, Inc. has never been a company to shy away from solving the hardest problems,” Musk stated.
Elon Musk
Rumored SpaceX-xAI merger gets apparent confirmation from Elon Musk
The comment follows reports that the rocket maker is weighing a transaction that could further consolidate Musk’s space and AI ventures.
Elon Musk appeared to confirm reports that SpaceX is exploring a potential merger with artificial intelligence startup xAI by responding positively to a post about the reported transaction on X.
Musk’s comment follows reports that the rocket maker is weighing a transaction that could further consolidate his space and AI ventures.
SpaceX xAI merger
As per a recent Reuters report, SpaceX has held discussions about merging with xAI, with the proposed structure potentially involving an exchange of xAI shares for SpaceX stock. The value, structure, and timing of any deal have not been finalized, and no agreement has been signed.
Musk appeared to acknowledge the report in a brief reply on X, responding “Yeah” to a post that described SpaceX as a future “Dyson Swarm company.” The comment references a Dyson Swarm, a sci-fi megastructure concept that consists of a massive network of satellites or structures that orbit a celestial body to harness its energy.
Reuters noted that two entities were formed in Nevada on January 21 to facilitate a potential transaction for the possible SpaceX-xAI merger. The discussions remain ongoing, and a transaction is not yet guaranteed, however.
AI and space infrastructure
A potential merger with xAI would align with Musk’s stated strategy of integrating artificial intelligence development with space-based systems. Musk has previously said that space-based infrastructure could support large-scale computing by leveraging continuous solar energy, an approach he has framed as economically scalable over time.
xAI already has operational ties to Musk’s other companies. The startup develops Grok, a large language model that holds a U.S. Department of Defense contract valued at up to $200 million. AI also plays a central role in SpaceX’s Starlink and Starshield satellite programs, which rely on automation and machine learning for network management and national security applications.
Musk has previously consolidated his businesses through share-based transactions, including Tesla’s acquisition of SolarCity in 2016 and xAI’s acquisition of X last year. Bloomberg has also claimed that Musk is considering a merger between SpaceX and Tesla in the future.
Tesla confirms that it finally solved its 4680 battery’s dry cathode process
Tesla Giga Texas to feature massive Optimus V4 production line
