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Tesla Semi battery weight criticisms are rooted in outdated ideas: EV expert
A good number of skeptics critical of battery-electric long-haulers like the Tesla Semi typically argue that the weight of the vehicles’ batteries makes them ineffective against competitors that are powered by diesel or hydrogen. As noted by an electric vehicle veteran and expert recently, however, these ideas are rooted in outdated ideas about battery weight. And if one considers more recent battery tech, electric Class 8 trucks may not only be feasible; they may actually be closer than expected.
In a recent piece on Bulk Distributor Magazine’s November/December 2020 issue, Auke Hoekstra, Senior Advisor for Electric Mobility at the Eindhoven University of Technology, noted that contrary to popular belief, long-haul trucks would not be the last vehicles to become battery-powered. This is in no small part due to the advancement of battery technology. Hoekstra noted that within five years, he believes that “electric trucks will become the logical choice for many bulk transporters” And within 10 years, vehicles like the Tesla Sei will likely dominate new sales.
The stunning progression of battery technology could be seen in just how much batteries have gotten better and cheaper over the years. Hoekstra noted that myths about electric trucks being too heavy were true 20 years ago, but not today. If electric long-haulers existed 20 years ago, they would likely be powered by lead-acid batteries, and assuming a battery size of 1 MWh, such a vehicle will require a pack that will likely weigh about 25 tons. That’s more than the entire payload of the truck. This is, of course, not the case today.
Hoekstra noted that when he wrote his first book about electric vehicles for the Dutch Ministry of Road Transport 13 years ago, lithium-ion batteries had started to emerge. Lithium-ion batteries offered reductions in weight, resulting in a 1 MWh pack weighing only about 10 tons. Today, this is even better, with modern electric cars having batteries that weigh about 5 kg per kWh or 5 tons per MWh. “I expect that with five years, that weight will be down to 3.5 tons. And it doesn’t stop there,” the EV veteran wrote.
Class 8 trucks like the Tesla Semi, which are designed from the ground up to be electric, will likely offer even better weight advantages. Hoekstra estimated that Tesla would see further weight reductions of about 2.5 to 3 tons due to the vehicle’s all-electric platform. “The electric motor is lighter, and you can get rid of the diesel tank and exhaust treatment. Then you place the electric motors between the wheels and lose the differential, driveshaft, and a host of other components,” he wrote.
What’s particularly interesting is that these estimates don’t even take into account the innovations that Tesla unveiled in its Battery Day event. Once Tesla’s 4680 tabless cells and structural battery packs enter the equation, the Semi becomes an even more compelling alternative to diesel-powered trucks. Hoekstra estimated that Tesla’s structural battery packs could save another ton to the Semi’s overall weight, seeing as the battery would practically displace the steel beams that give traditional Class 8 long-haulers their rigidity. With this in mind, the EV veteran noted that “battery weight will soon be a problem of the past.”
There are other advantages to electric trucks that were highlighted by Hoekstra in his piece, such as the cost savings that will result from the use of a fleet of electric trucks. This is something that Tesla has highlighted in the past, with CEO Elon Musk stating during the vehicle’s unveiling that the Semi will vastly undercut diesel-powered rivals when it comes to operating costs. Couple this with the low maintenance requirements of EVs, as well as the fact that batteries now last much longer, and trucks like the Tesla Semi will likely become very attractive options for operators in the very near future.
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 launched the all-electric, steering wheel-less, and pedal-less Cybercab last night at a quiet and small event in downtown Austin, Texas.
The launch, which marked the beginning of unsupervised ride-hailing for Tesla’s Robotaxi platform with Cybercab, has already caught the attention of the National Highway Traffic Safety Administration (NHTSA) who has more questions.
NHTSA opened an Audit Query (AQ) into the Cybercab’s Federal Motor Vehicle Safety Standards (FMVSS) certification that Tesla gave the vehicle. Manufacturers self-certify vehicles much of the time to avoid excessive regulatory delays.
Tesla Cybercab interior, note the lack of steering wheel and pedals. (Credit: @niccruzpatane/X< /a>)
However, the agency needs more information; it said in a summary:
“On September 3, 2026, Tesla began commercial deployment with a small number of its Cybercab vehicles in Austin, Texas. Tesla notified the Agency that it certified those Cybercab vehicles as compliant with all applicable Federal Motor Vehicle Safety Standards (FMVSS). Tesla also notified the Agency that it plans to gradually expand commercial deployment of the Cybercab to include additional vehicles and locations.”
It also went on to state that the Cybercab lacks traditional automotive controls, which is a groundbreaking move. The process is entirely new to the NHTSA, which gives the agency some leverage to put Tesla’s launch under a microscope:
“The vehicles lack permanently attached, conventional manual controls, such as a brake pedal, gas pedal, steering wheel, and mirrors. NHTSA is opening this AQ to examine the process and technical data on which Tesla relied when certifying the Cybercab and related issues. Among other things, NHTSA will consider the extent to which Tesla’s certification depended on determinations that certain FMVSS are inapplicable to the Cybercab.”
Tesla has added 45 Cybercab units to its fleet of Robotaxi-enabled cars in Austin, according to public documents the company submitted to the State of Texas over the past week. Enabling this level of self-driving is something Tesla has worked toward for many years, and now that it is finally here, it seems more than reasonable that regulatory agencies will have some questions.
Many outlets might try to frame this as a negative, but it is truly an agency looking to gain more information about groundbreaking tech that Tesla has been developing for years.
In an effort to keep riders, pedestrians, and property safe, any and all data accumulated from these first days, weeks, and months of rides will likely be shared with the NHTSA to enable broader rollout strategies across the United States and more in the future.
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Tesla Cybercab is coming to Asia this month as US service officially begins
Tesla Asia says Cybercab will be on display in Hong Kong, Tokyo, Beijing and Shanghai this month.
Tesla’s Cybercab is heading to Asia. The official Tesla Asia account posted on X Thursday, inviting Cybercab fans to “Come experience the future of autonomy in Hong Kong, Tokyo, Beijing & Shanghai.” The post went up within hours of Tesla’s own Cybercab milestone in Texas, where the company said Thursday it had begun offering rides in across Austin.
Exact dates and venues for the Asia tour haven’t been released yet, though Tesla Hong Kong replied to the announcement with “Cybercab will be on display in Hong Kong soon,” while Tesla Japan’s response pointed fans to a sign up page for updates. Neither post mentions test rides or a service area, and nothing so far suggests Tesla is launching Robotaxi operations in any of the four cities. Based on how Tesla has run past Cybercab tours, in Europe in late 2024 and at US shopping centers that same December, the Asia stops are almost certainly static displays at Tesla stores or public venues as a means to stimulate buzz for its future driverless ride-hailing service in the big cities.
Cybercab will be on display in Asia this month!
Come experience the future of autonomy in Hong Kong, Tokyo, Beijing & Shanghai. pic.twitter.com/wGmmEastfX— Tesla Asia (@Tesla_Asia) September 4, 2026
The timing lines up with Tesla’s only prior Cybercab appearance in the region, a booth at the China International Import Expo in Shanghai last November, which Teslarati covered at the time. At that event, Tesla’s regional general manager for Shanghai framed the car as evidence of the company’s broader mission, a message Tesla has since formalized in its Master Plan Part IV, which states that “autonomous vehicles have the capacity to dramatically improve the affordability, availability and safety of transportation while reducing pollution, particularly in our increasingly dense global cities.” The same document is where Tesla lays out its “sustainable abundance” framing for Cybercab and Optimus alike, describing the two as the hardware behind an AI driven push to cut the cost of transportation and labor at scale.
Whether Cybercab actually operates as a robotaxi anywhere in Asia remains an open question, considering China has already pushed an autonomous ride-hailing market that’s run on homegrown players like Baidu’s Apollo Go and Pony AI. For now, the four city tour reads as a marketing push timed to Austin’s momentum.
Tesla Full Self-Driving will now overtake manual driving to avoid disaster
Tesla Cybercab launch catches NHTSA’s attention who wants to know more
