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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 has reached a notable benchmark in its autonomous driving program after its Robotaxi fleet surpassed one million miles of unsupervised operation. The company made the announcement during its Cybercab event in Austin on September 3.
Tesla Vice President of AI Ashok Elluswamy told attendees he was happy to report the fleet had achieved one million miles of unsupervised Robotaxi operation as a testament to safety.
The new total marked a sharp increase from the 380,000 unsupervised miles Tesla disclosed during its second-quarter 2026 earnings update in late July.
In roughly six weeks, the company added about 620,000 miles. That acceleration followed Tesla’s decision to remove in-vehicle safety monitors from most of its operations outside the San Francisco Bay Area.
Credit: Tesla
Tesla first launched Robotaxi service in Austin in June 2025 with safety drivers present. It later began fully unsupervised rides and expanded into Dallas, Houston, Miami, Orlando, and Tampa. The San Francisco Bay Area remains the exception, where a safety monitor still rides in the vehicle under California permitting rules.
The company has not released a city-by-city breakdown of the one million unsupervised miles.
The milestone arrived as Tesla began offering public Cybercab rides in Austin. The purpose-built vehicle has no steering wheel or pedals and is designed only for autonomous ride-hailing. Production versions joined the existing fleet of modified Tesla vehicles already operating in the service.
Tesla’s unsupervised mileage is growing at a double-digit weekly rate according to earlier company comments, yet its fleet size remains modest compared with established competitors. Waymo has accumulated more than 200 million fully autonomous rider-only miles. Tesla has described its own unsupervised operations as having recorded zero notable incidents in the period leading up to the July update.
The one-million-mile figure reflects Tesla’s shift from supervised testing to broader driverless service in multiple states. It also highlights the company’s strategy of using both existing Model Y vehicles and the new Cybercab to scale its network.
Credit: Tesla
Whether the rapid recent growth continues will depend on further city expansions, regulatory approvals, and the performance of the purpose-built Cybercab in everyday paid rides. Tesla has not specified how many of the latest miles involved the new vehicle versus the rest of the fleet.
The announcement underscores Tesla’s progress toward a larger robotaxi network while illustrating the remaining gap in total autonomous experience relative to longer-operating rivals.
Tesla AI lead Ashok Elluswamy said this week that 24-hour Robotaxi service is close. Replying on X to a rider who wanted Cybercab trips all night, he wrote that the capability would arrive “next month or so” once “the next tech to merge on the v15 plan” is ready.
The comment landed on September 4, one day after Tesla opened public Cybercab rides in Austin. It is the clearest near-term timeline yet for overnight unsupervised operation. Tesla’s paid Robotaxi network currently runs from 6 a.m. to 10 p.m. seven days a week across Austin, Dallas, Houston, Miami, Orlando, and Tampa.
next month or so. the next tech to merge on the v15 plan will enable it.
— Ashok Elluswamy (@aelluswamy) September 4, 2026
That 16-hour window is shorter than the 6 a.m. to 2 a.m. schedule the company used for much of the prior year.
Elluswamy did not name the specific feature or say whether the change would apply first to purpose-built Cybercabs, the existing Model Y fleet, or both. He also offered no city-by-city rollout list. The link to Full Self-Driving v15 is nevertheless significant.
Tesla has described v15 as a step-change architecture with seven parallel improvement tracks and roughly ten times more parameters than earlier builds. Early versions of that software already operate on the Robotaxi fleet and contain about 40 percent of the planned gains.
By July 2026, the unsupervised fleet had logged more than 380,000 miles across six cities in two states with what the company called an impeccable safety record and no notable incidents caused by the vehicles themselves. Tesla has repeatedly argued that camera-based end-to-end neural networks, rather than extra sensors, are the core of the solution.
Overnight service would test that claim in lower-light conditions and would also raise vehicle utilization, a key variable for Robotaxi unit economics. The company has already begun using public Superchargers at night and is building dedicated Robotaxi charging sites.
Riders have asked why software must change if the cars already drive in the dark. The practical answer appears to be reliability and scale: Tesla has held back mass expansion until more of the v15 stack is merged, citing the need for higher confidence before putting thousands of unoccupied vehicles on streets around the clock.
If the next module arrives on the timetable Elluswamy sketched, 24-hour service could begin in October 2026 in at least some markets.
That would mark a shift from a daytime-bounded pilot to a service that can run whenever demand exists, including the late-night hours that have so far remained out of reach.
Tesla is beginning to roll out Full Self-Driving Supervised v14.3.9 with a new active safety layer that can take control even when the driver is operating the car manually.
Tesla AI said the software can activate FSD on the driver’s behalf when an imminent collision is detected and Automatic Emergency Braking may not be enough. It may also engage if the system detects heavy distraction or an accidental FSD disengagement.
FSD Supervised v14.3.9 starting to roll out shortly
This release includes a new active safety feature set: FSD Supervised can now activate on your behalf when an imminent collision is detected and Automatic Emergency Braking (AEB) may not be enough.
It may also engage if we…
— Tesla AI (@Tesla_AI) September 4, 2026
The capability is essentially Automatic Collision Evasion. However, unlike conventional AEB, which mainly applies the brakes in a straight line, this feature can use steering, braking, and acceleration together if the car calculates that stopping alone will not prevent impact and a safer path exists. The system may change lanes or move toward a shoulder when conditions allow, then continue driving after the immediate threat is handled rather than simply coming to a stop.
The intervention is meant as a last-resort safety net, not a replacement for attentive driving.
Tesla Full Self-Driving v14.3.7 early review: FSD saved me from an accident
Tesla’s own description still frames FSD as supervised assistance. Secondary reports on internal release notes say the feature can fire while the car is being driven manually if cabin-camera monitoring suggests the driver is not sufficiently attentive, such as reaching toward the back seat, or if FSD appears to have been turned off unintentionally.
After the emergency maneuver, the car is expected to alert the driver and request a return to manual control.
The safety case is straightforward. Many collisions happen in the last second because a driver is looking away, fumbles a control, or faces an obstacle that braking cannot fully solve. A system that can both recognize that AEB is insufficient and execute a coordinated evasive path can reduce those remaining high-severity events.
Re-engaging after accidental disengagement also addresses a practical failure mode: a small steering nudge that drops FSD at the worst moment. The advantage is a background safety net that uses the same vision stack already running in v14, instead of leaving the car solely to emergency braking once the driver is no longer in command.
The feature still depends on FSD being enabled and, according to reports, an active FSD purchase or subscription. It does not make the vehicle unsupervised. Drivers remain responsible, and Tesla has not published how often the system is expected to intervene or how it will handle false positives.
If the rollout is conservative and the false-alarm rate stays low, the update is a meaningful step: FSD is no longer only a feature the driver turns on. In the rare moments when disaster is already forming, it can step in.
Tesla crosses major Unsupervised Self-Driving milestone
Tesla Robotaxi will be a 24/7 service: here’s when
