Tesla’s Battery Day detailed a variety of topics that are related to the future of cell manufacturing efficiency. However, the presentation also showed how the automaker is improving the design of its vehicles by utilizing a new battery architecture. Tesla plans to adopt the same strategy within its vehicles to improve mass, range, and the structural integrity of its vehicles.
Teslarati reported earlier this year that Tesla would be using a single-piece casting design on the Model Y. The improved casting eliminates 79 parts per car, which not only increases manufacturing efficiency but also increases safety for drivers. The cost of each vehicle’s rear underbody design also decreases by 40% thanks to the casting, which is performed by a massive machine known as the Giga Press.
The single-piece rear casting is made from Tesla’s own high-pressure aluminum alloy that has a high strength thanks to no heat treatment or coatings that would take away from the structural integrity of the design. Heat treating a casting of this size after manufacturing causes deformation, CEO Elon Musk said during the event.
However, the manufacturing team at Tesla also drew inspiration from aircraft wings to improve the structural integrity of its vehicles. While the casting improves manufacturing efficiency and strength, the positioning of structural batteries eliminates excess structure from the battery packs, increasing density.
“The non-cell portion of the battery has negative mass,” Musk said. “We saved more mass in the rest of the vehicle than in the non-cell portion of the battery. So how do you really minimize the mass of the battery? Make it negative.”
The minimization of negative mass allowed the automaker to increase the density of the battery pack. Individual cells could be positioned more efficiently because excessive structures within the pack itself were eradicated. The new Tesla battery design is completely free of any negative mass, which improves pack density along with structural integrity.
“The pack itself is structural,” Musk stated.
Additionally, the filler within the Model 3 and Model Y packs, which currently uses a flame retardant, now uses a structural adhesive and flame retardant. This adhesive effectively attaches the cells to the top and bottom sheets of the pack. “This allows you to do sheer transfer between the upper and lower sheet,” which increases stiffness and prevents major deformation in the event of a crash.
Improvements in the casting design of Tesla’s future cars and the newly designed battery architecture, which uses new materials and strategies to increase stiffness, will increase the already safe vehicles that the company manufactures. Tesla already holds three separate five-star crash safety ratings with the Model S, Model 3, and Model X. The Model Y has not yet been tested, but the vehicle does use the one-piece rear casting design already at the Fremont production facility.
Tesla’s Battery Day did not disappoint. While the blueprint to cell manufacturing efficiency was laid out, the company also showed how battery layout and architecture could increase Tesla’s vehicle safety. The new design revolutionizes EVs as a whole and will eventually lead to more safety than previously displayed.
Tesla is updating Cybertruck owners on its timeline of a massive feature that has yet to ship: Powershare with Powerwall.
Powershare is a bidirectional charging feature exclusive to Cybertruck, which allows the vehicle’s battery to act as a portable power source for homes, appliances, tools, other EVs, and more. It was announced in late 2023 as part of Tesla’s push into vehicle-to-everything energy sharing, and acting as a giant portable charger is the main advantage, as it can provide backup power during outages.
Cybertruck’s Powershare system supports both vehicle-to-load (V2L) and vehicle-to-home (V2H), making it flexible and well-rounded for a variety of applications.
However, even though the feature was promised with Cybertruck, it has yet to be shipped to vehicles. Tesla communicated with owners through email recently regarding Powershare with Powerwall, which essentially has the pickup act as an extended battery.
Powerwall discharge would be prioritized before tapping into the truck’s larger pack.
However, Tesla is still working on getting the feature out to owners, an email said:
“We’re writing to let you know that the Powershare with Powerwall feature is still in development and is now scheduled for release in mid-2026.
This new release date gives us additional time to design and test this feature, ensuring its ability to communicate and optimize energy sharing between your vehicle and many configurations and generations of Powerwall. We are also using this time to develop additional Powershare features that will help us continue to accelerate the world’s transition to sustainable energy.”
Owners have expressed some real disappointment in Tesla’s continuous delays in releasing the feature, as it was expected to be released by late 2024, but now has been pushed back several times to mid-2026, according to the email.
Foundation Series Cybertruck buyers paid extra, expecting the feature to be rolled out with their vehicle upon pickup.
Cybertruck’s Lead Engineer, Wes Morrill, even commented on the holdup:
As a Cybertruck owner who also has Powerwall, I empathize with the disappointed comments.
To their credit, the team has delivered powershare functionality to Cybertruck customers who otherwise have no backup with development of the powershare gateway. As well as those with solar…
— Wes (@wmorrill3) December 12, 2025
He said that “it turned out to be much harder than anticipated to make powershare work seamlessly with existing Powerwalls through existing wall connectors. Two grid-forming devices need to negotiate who will form and who will follow, depending on the state of charge of each, and they need to do this without a network and through multiple generations of hardware, and test and validate this process through rigorous certifications to ensure grid safety.”
It’s nice to see the transparency, but it is justified for some Cybertruck owners to feel like they’ve been bait-and-switched.
Tesla has opened its northernmost Supercharger in Fairbanks, Alaska, with eight V4 stalls located in one of the most frigid cities in the U.S.
Located just 196 miles from the Arctic Circle, Fairbanks’s average temperature for the week was around -12 degrees Fahrenheit. However, there are plenty of Tesla owners in Alaska who have been waiting for more charging options out in public.
There are only 36 total Supercharger stalls in Alaska, despite being the largest state in the U.S.
Eight Superchargers were added to Fairbanks, which will eventually be a 48-stall station. Tesla announced its activation today:
North America’s northernmost Supercharger Fairbanks, AK (8 stalls) opened to public. https://t.co/M4l04DZ6B5 pic.twitter.com/zyL6bDuA93
— Tesla Charging (@TeslaCharging) December 12, 2025
The base price per kWh is $0.43 at the Fairbanks Supercharger. Thanks to its V4 capabilities, it can charge at speeds up to 325 kW.
Despite being the northernmost Supercharger in North America, it is not even in the Top 5 northernmost Superchargers globally, because Alaska is south of Norway. The northernmost Supercharger is in Honningsvåg, Norway. All of the Top 5 are in the Scandanavian country.
Tesla’s Supercharger expansion in 2025 has been impressive, and although it experienced some early-quarter slowdowns due to V3-to-V4 hardware transitions, it has been the company’s strongest year for deployments.
🚨🚨 Tesla Supercharging had a HUGE year, and they deserve to be recognized.
🍔 Opened Tesla Diner, a drive-in movie theater with awesome, Chef-curated cuisine
🔌 Gave access to Superchargers to several EV makers, including Hyundai, Genesis, Mercedes-Benz, Kia, Lucid, Toyota,… pic.twitter.com/yYT2QEbqoW
— TESLARATI (@Teslarati) December 10, 2025
Through the three quarters of 2025, the company has added 7,753 stations and 73,817 stalls across the world, a 16 percent increase in stations and an 18 percent increase in stalls compared to last year.
Tesla is on track to add over 12,000 stalls for the full year, achieving an average of one new stall every hour, an impressive statistic.
Recently, the company wrapped up construction at its Supercharger Oasis in Lost Hills, California, a 168-stall Supercharger that Tesla Solar Panels completely power. It is the largest Supercharger in the world.
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Tesla shocks with latest Robotaxi testing move
Why Tesla has chosen to use a couple of Model S units must have a reason; the company is calculated in its engineering and data collection efforts, so this is definitely more than “we just felt like giving our drivers a change of scenery.”
Tesla Model S vehicles were spotted performing validation testing with LiDAR rigs in California today, a pretty big switch-up compared to what we are used to seeing on the roads.
Tesla utilizes the Model Y crossover for its Robotaxi fleet. It is adequately sized, the most popular vehicle in its lineup, and is suitable for a wide variety of applications. It provides enough luxury for a single rider, but enough room for several passengers, if needed.
However, the testing has seemingly expanded to one of Tesla’s premium flagship offerings, as the Model S was spotted with the validation equipment that is seen entirely with Model Y vehicles. We have written several articles on Robotaxi testing mules being spotted across the United States, but this is a first:
🚨 Tesla is using Model S vehicles fitted with LiDAR rigs to validate FSD and Robotaxi, differing from the Model Ys that it uses typically
Those Model Y vehicles have been on the East Coast for some time. These Model S cars were spotted in California https://t.co/CN9Bw5Wma8 pic.twitter.com/UE55hx5mdd
— TESLARATI (@Teslarati) December 11, 2025
Why Tesla has chosen to use a couple of Model S units must have a reason; the company is calculated in its engineering and data collection efforts, so this is definitely more than “we just felt like giving our drivers a change of scenery.”
It seems to hint that Tesla could add a premium, more luxury offering to its Robotaxi platform eventually. Think about it: Uber has Uber Black, Lyft has Lyft Black. These vehicles and services are associated with a more premium cost as they combine luxury models with more catered transportation options.
Tesla could be testing the waters here, and it could be thinking of adding the Model S to its fleet of ride-hailing vehicles.
Reluctant to remove the Model S from its production plans completely despite its low volume contributions to the overall mission of transitioning the world to sustainable energy, the flagship sedan has always meant something. CEO Elon Musk referred to it, along with its sibling Model X, as continuing on production lines due to “sentimental reasons.”
However, its purpose might have been expanded to justify keeping it around, and why not? It is a cozy, premium offering, and it would be great for those who want a little more luxury and are willing to pay a few extra dollars.
Of course, none of this is even close to confirmed. However, it is reasonable to speculate that the Model S could be a potential addition to the Robotaxi fleet. It’s capable of all the same things the Model Y is, but with more luxuriousness, and it could be the perfect addition to the futuristic fleet.
Tesla updates Cybertruck owners about key Powershare feature
Tesla’s northernmost Supercharger in North America opens
