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.
News
Tesla FSD’s newest model is coming, and it sounds like ‘the last big piece of the puzzle’
“There’s a model that’s an order of magnitude larger that will be deployed in January or February 2026.”
Tesla Full Self-Driving’s newest model is coming very soon, and from what it sounds like, it could be “the last big piece of the puzzle,” as CEO Elon Musk said in late November.
During the xAI Hackathon on Tuesday, Musk was available for a Q&A session, where he revealed some details about Robotaxi and Tesla’s plans for removing Robotaxi Safety Monitors, and some information on a future FSD model.
While he said Full Self-Driving’s unsupervised capability is “pretty much solved,” and confirmed it will remove Safety Monitors in the next three weeks, questions about the company’s ability to give this FSD version to current owners came to mind.
Musk said a new FSD model is coming in about a month or two that will be an order-of-magnitude larger and will include more reasoning and reinforcement learning.
He said:
“There’s a model that’s an order of magnitude larger that will be deployed in January or February 2026. We’re gonna add a lot of reasoning and RL (reinforcement learning). To get to serious scale, Tesla will probably need to build a giant chip fab. To have a few hundred gigawatts of AI chips per year, I don’t see that capability coming online fast enough, so we will probably have to build a fab.”
NEWS: Elon Musk says FSD Unsupervised is “pretty much solved at this point” and that @Tesla will be launching Robotaxis with no safety monitors in about 3 weeks in Austin, Texas. He also teased a new FSD model is coming in about 1-2 months.
“We’re just going through validation… https://t.co/Msne72cgMB pic.twitter.com/i3wfKX3Z0r
— Sawyer Merritt (@SawyerMerritt) December 10, 2025
It rings back to late November when Musk said that v14.3 “is where the last big piece of the puzzle finally lands.”
With the advancements made through Full Self-Driving v14 and v14.2, there seems to be a greater confidence in solving self-driving completely. Musk has also personally said that driver monitoring has been more relaxed, and looking at your phone won’t prompt as many alerts in the latest v14.2.1.
This is another indication that Tesla is getting closer to allowing people to take their eyes off the road completely.
Along with the Robotaxi program’s success, there is evidence that Tesla could be close to solving FSD. However, it is not perfect. We’ve had our own complaints with FSD, and although we feel it is the best ADAS on the market, it is not, in its current form, able to perform everything needed on roads.
But it is close.
That’s why there is some legitimate belief that Tesla could be releasing a version capable of no supervision in the coming months.
All we can say is, we’ll see.
Investor's Corner
SpaceX IPO is coming, CEO Elon Musk confirms
However, it appears Musk is ready for SpaceX to go public, as Ars Technica Senior Space Editor Eric Berger wrote an op-ed that indicated he thought SpaceX would go public soon. Musk replied, basically confirming it.
Elon Musk confirmed through a post on X that a SpaceX initial public offering (IPO) is on the way after hinting at it several times earlier this year.
It also comes one day after Bloomberg reported that SpaceX was aiming for a valuation of $1.5 trillion, adding that it wanted to raise $30 billion.
Musk has been transparent for most of the year that he wanted to try to figure out a way to get Tesla shareholders to invest in SpaceX, giving them access to the stock.
He has also recognized the issues of having a public stock, like litigation exposure, quarterly reporting pressures, and other inconveniences.
However, it appears Musk is ready for SpaceX to go public, as Ars Technica Senior Space Editor Eric Berger wrote an op-ed that indicated he thought SpaceX would go public soon.
Musk replied, basically confirming it:
As usual, Eric is accurate
— Elon Musk (@elonmusk) December 10, 2025
Berger believes the IPO would help support the need for $30 billion or more in capital needed to fund AI integration projects, such as space-based data centers and lunar satellite factories. Musk confirmed recently that SpaceX “will be doing” data centers in orbit.
AI appears to be a “key part” of SpaceX getting to Musk, Berger also wrote. When writing about whether or not Optimus is a viable project and product for the company, he says that none of that matters. Musk thinks it is, and that’s all that matters.
It seems like Musk has certainly mulled something this big for a very long time, and the idea of taking SpaceX public is not just likely; it is necessary for the company to get to Mars.
The details of when SpaceX will finally hit that public status are not known. Many of the reports that came out over the past few days indicate it would happen in 2026, so sooner rather than later.
But there are a lot of things on Musk’s plate early next year, especially with Cybercab production, the potential launch of Unsupervised Full Self-Driving, and the Roadster unveiling, all planned for Q1.
Tesla has added the 15th automaker to the growing list of companies whose EVs can utilize the Supercharger Network this year, as BMW is the latest company to gain access to the largest charging infrastructure in the world.
BMW became the 15th company in 2025 to gain Tesla Supercharger access, after the company confirmed to its EV owners that they could use any of the more than 25,000 Supercharging stalls in North America.
Welcome @BMW owners.
Download the Tesla app to charge → https://t.co/vnu0NHA7Ab
— Tesla Charging (@TeslaCharging) December 10, 2025
Newer BMW all-electric cars, like the i4, i5, i7, and iX, are able to utilize Tesla’s V3 and V4 Superchargers. These are the exact model years, via the BMW Blog:
- i4: 2022-2026 model years
- i5: 2024-2025 model years
- 2026 i5 (eDrive40 and xDrive40) after software update in Spring 2026
- i7: 2023-2026 model years
- iX: 2022-2025 model years
- 2026 iX (all versions) after software update in Spring 2026
With the expansion of the companies that gained access in 2025 to the Tesla Supercharger Network, a vast majority of non-Tesla EVs are able to use the charging stalls to gain range in their cars.
So far in 2025, Tesla has enabled Supercharger access to:
- Audi
- BMW
- Genesis
- Honda
- Hyundai
- Jaguar Land Rover
- Kia
- Lucid
- Mercedes-Benz
- Nissan
- Polestar
- Subaru
- Toyota
- Volkswagen
- Volvo
Drivers with BMW EVs who wish to charge at Tesla Superchargers must use an NACS-to-CCS1 adapter. In Q2 2026, BMW plans to release its official adapter, but there are third-party options available in the meantime.
They will also have to use the Tesla App to enable Supercharging access to determine rates and availability. It is a relatively seamless process.
Tesla FSD’s newest model is coming, and it sounds like ‘the last big piece of the puzzle’
SpaceX IPO is coming, CEO Elon Musk confirms
