Tesla’s Battery Day is coming tomorrow after the electric car maker’s 2020 Annual Shareholder Meeting. During the event, Tesla is expected to discuss the details of its next-generation battery cells, as well as their role in the world’s acceleration in sustainable energy. Actual details about Battery Day have been pretty scarce save for a few potential leaks, but that has not stopped the Tesla community from speculating about what the highly-anticipated event would involve.
A concise summary of the current expectations for Battery Day was recently shared by Tesla Daily’s Rob Maurer, who compiled a list of topics that the electric car maker could cover during the event. Following then is a list of expectations about what Tesla could discuss tomorrow, as the company finally shows the world what it has been working on with regards to its battery technology.
A New Cell Design
Tesla has been teasing that it would be going into the production of battery cells. So far, leaks suggest that the company is about to adopt a larger form factor for its batteries, similar to how Tesla introduced the 2170 cells for the Model 3, which were larger than the 18650 cells used in the Model S and Model X. Leaks have pointed to Tesla’s new cells possibly adopting a 54×98 form factor, which has about 10x the volume of a 2170 cell.
With larger form factors, the electrons and the ions travel larger distances as they move around in the cell, generating more friction and heat. This is a huge downside to larger cells, but Tesla’s tabless battery patent may hold the key to solving this issue. With a tabless battery cell design, the distance traveled by electrons and ions is largely reduced, limiting the disadvantages inherent among large cells. Such a design has several advantages, including better energy density and a more efficient manufacturing process.
Battery Chemistry
Speculations are abounding that Tesla may discuss the amount of silicon that it is using in the anode of its next-generation cells. The more silicon that is used, the better the energy density. However, the utilization of silicon usually results in cracked anodes over time, reducing battery performance and life. Introducing more silicon into the anode is something that battery researchers have been attempting to accomplish for a while now, so it would be quite interesting if the electric car maker would announce some headway into its silicon use as well.
Tesla may also discuss Maxwell’s technology and how it is being used for the company’s electric cars and energy storage devices. Maxwell has developed numerous innovations prior to its acquisition by Tesla, though the most relevant part of the company’s work in relation to the electric car maker is arguably its dry battery electrode tech. Considering that traditional lithium-ion batteries produce their electrodes in a wet slurry format (a rather lengthy process), dry electrode technology could vastly improve not only the energy density of Tesla’s cells, they could improve the production output of the batteries themselves as well.
Cell-to-Pack Innovations
Tesla’s battery packs today feature cells that are packed into modules that are then packed into a battery pack. Back in the days of the original Roadster, battery modules were used as a means for the company to take out parts of the battery that may need to be replaced without taking out the entire pack. That was 12 years ago, however, and much has happened since then. Tesla has transitioned from a budding niche electric car maker to the manufacturer of the market’s best-selling EVs.
As Elon Musk noted in the past, battery modules today are pretty much just an extra step, taking up weight without really serving a legitimate purpose. Musk then stated that the future is cell to pack without modules, suggesting that the company’s next-generation batteries will be using a cell-to-pack design. Such an innovation gives numerous benefits to Tesla, from lower production costs to possibly even better energy density.
Battery Manufacturing and the Roadrunner Line
Elon Musk has always been pretty transparent about Tesla’s mission, which is to accelerate the advent of sustainable energy. Having enough batteries to enable such a transition is key to this goal. With this in mind, the potential innovations that Tesla will be discussing in Battery Day — a larger form factor that would allow the company to produce fewer cells to get the same amount of energy; a tabless cell design that could make production easier; dry electrode tech that could greatly increase the production capacity density of each battery; and a cell-to-pack design that should allow the production of batteries with less equipment at less cost — could ultimately pave the way for electric vehicles and energy storage products that are significantly better than the industry standard today.
The Roadrunner project in Fremont is expected to be a central component of Tesla’s battery manufacturing plans, with attendees to the event being shown just how fast the company could produce its battery cells using its in-house production process. Elon Musk seems to be hyping the Roadrunner line recently on Twitter as well, when he made references to a game called “Factorio,” which happens to be a title focused on growing and maintaining advanced, efficient factories.
The Million-Mile Battery
The million-mile battery has been heavily speculated for Battery Day. Tesla’s electric cars are already capable of lasting long despite heavy use, but with batteries and powertrains that could last a million miles, the company could create a generation of vehicles that are designed to be always operational for an extended period of time. Million-mile batteries are then crucial for Tesla’s plans to roll out a Robotaxi service, which involves vehicles traveling long distances every year.
The Plaid Powertrain
With Tesla’s battery innovations in mind, speculations are high that the company would unveil its first vehicles that would carry its next-generation cells on Battery Day. Among Tesla’s ongoing projects, the Roadrunner cells seem to be a perfect match for cars like the Plaid Model S, Plaid Model X, and next-generation Roadster. All three vehicles have been confirmed by Elon Musk to feature the company’s upcoming “Plaid Powertrain,” which is something that has been heavily teased for some time now. Interestingly enough, updates on Tesla’s Plaid vehicles have been pretty scarce lately, making an announcement on Battery Day somewhat likely.
Watch Rob Maurer’s full Tesla Battery Day predictions in the video below.
Energy
Tesla Model 3 and Model Y can now do what only Cybertruck could
Tesla Model 3 and Model Y can power your home with Powerwall 3 during outages.
Tesla has turned its two top sellers into backup batteries for the house.
Tesla Energy announced on Tuesday that Powershare Home Backup is now available for new Model 3 and Model Y vehicles paired with a Powerwall 3, saying the car can “extend your home backup by over 2 days.” Minutes later, Tesla’s main account quoted the post with a broader pitch: “With Powerwall 3, every Tesla can now serve as your home’s backup battery.”
Until this week, the Cybertruck was the only Tesla that could send power back into a home, and that capability only began working alongside Powerwall 3 last month, after years of ambitious targets.
Tesla’s updated Powershare page says every Model 3 and Model Y ordered in the U.S. or Puerto Rico on or after October 1, 2026 can use the feature. Some, but not all, earlier cars also qualify. Owners can check on the touchscreen under Software, then Additional Vehicle Information, where a capable car shows “Powershare Support: Enabled.” As Electrek reported, bidirectional power on the two cars runs through an inverter Tesla calls PCS2 Lite, and the company has not said when that part entered production on each trim.
The home side is simpler. A house that already has a Powerwall 3 and either a Wall Connector 3 or Universal Wall Connector needs no additional equipment, and Tesla says compatibility is enabled through a software update. When the grid drops, the Powerwall and the car work together, with up to 11.52 kW of continuous power available. Tesla’s “over two days” estimate assumes a home using 30 kWh per day and a car starting at a 90 percent charge. Standard trims are rated for up to two days, while the Cybertruck adds more than three.
There are limits. Powerwall 2 and Powerwall+ support is listed as “coming soon.” Model S and Model X are not included, and Grid Support, the program that lets Cybertruck owners in Texas send power back to the grid during demand spikes for bill credits, is not available for Model 3 or Model Y.
The rollout also lines up with something Elon Musk said more than three years ago. At Tesla’s March 2023 Investor Day, Musk said, “I don’t think very many people are going to want to use bidirectional charging, unless you have a Powerwall.” Tesla has now shipped the feature for its volume cars with exactly that requirement attached.
The Powerwall pairing was the hard part on Cybertruck. Tesla told owners in December 2025 that Powershare with Powerwall had been pushed to mid 2026, and lead engineer Wes Morrill explained that two devices capable of forming a home’s grid have to negotiate which one leads during an outage, across multiple generations of hardware. With that work done for the truck, Tesla was able to extend it to the Model 3 and Model Y within a month.
Ford and GM have offered home backup from their EVs for several years, but both require a separate inverter and backup hardware. Tesla’s version leans on equipment many Powerwall 3 owners already have on the wall. Powershare for the two cars also ships as part of software update 2026.38.3, the same release that began delivering Halloween Mode on Tuesday.
News
Tesla ships ‘spooky’ Halloween Mode with creepy and fun features
Tesla is now starting to ship a “Halloween Mode” that is filled with some creepy and fun features; the company says, “This spooky update turns your Tesla into a haunted house on wheels.”
The update is just the latest in a series of updates that Tesla typically ships out in a seasonal fashion. The Spring and Summer Updates provided some fun novelty items while also packing some cool features that are actually useful for the ownership experience.
This one seems to be more fun-forward, and there are not any updates to the Full Self-Driving suite or overall operation of the vehicle. Instead, these novelty features are geared toward getting you in the mood for the Fall and Halloween.
Halloween Mode now rolling out 🎃
This spooky update turns your Tesla into a haunted house on wheels
– Ghost costume on your car’s avatar
– Enable Trick or Treat to play spooky sounds & flicker the lights when visitors approach
– New haunting light show, wraps & lock sound
– A rather chilling Photobooth
– Frighten people remotely by speaking through the app…your car will say it in a voice of its own
Side effects may include neighborhood notoriety
— Tesla (@Tesla) October 6, 2026
New Ghost Costume on Car Avatar
Driver Visualization will now show your vehicle as a ghost, as an all-white sheet is draped over the vehicle. Pedestrians are turned into mummies or skeletons, and other vehicles are all a spooky green:

Credit: Tesla
Additionally, the Park Scene with your Tesla now displays that ghost costume draped over your vehicle in the foreground of a scary backdrop with Jack-o-Lanterns and a haunted house:

Credit: Tesla
Trick or Treat Mode
Trick or Treat Mode will enable the vehicle to play spooky sounds and flicker the lights as visitors approach. This might be a nice touch for when you’re handing out candy to kids on Halloween Night.
Other Features
Tesla is also adding a new Light Show, new Wrap Options, and a new Lock Sound with this update.

Credit: Tesla
Additionally, Photobooth has a new Halloween option:

Credit: Tesla
You will also be able to speak remotely through the app and transmit your voice to people outside, which is not a new feature, but the car will say it in a voice of its own, which is a new feature with that bullhorn-like feature.
Investor's Corner
SpaceX reveals how its 1 Million AI satellite network will work and prevent space collisions
SpaceX reveals plans for one million Starmind AI satellites and calls out operators hiding maneuvers.
SpaceX has put the largest satellite count it has ever published into writing, and it says that plan only works if every other operator in orbit starts sharing what it knows.
In a new Space Safety page highlighted Tuesday morning by Sawyer Merritt on X, SpaceX said it “plans to operate up to 100,000 Starlink satellites and up to 1 million Starmind AI satellites to meet the growing demand for broadband and supercompute.” Starlink has a little over 11,000 satellites in orbit today, so the target alone implies roughly a ninefold expansion of the broadband network.
Starmind is SpaceX’s orbital AI compute constellation. Elon Musk confirmed the Starmind name in June after an xAI trademark filing surfaced, and in August SpaceX said it was working with Nvidia on the compute payload. The FCC accepted the filing for up to one million satellites back in February.
FCC accepts SpaceX filing for 1 million orbital data center plan
SpaceX also released a new render of what a full Starmind constellation could look like. Alongside it, SpaceX VP Michael Nicolls explained why the satellites will not operate on their own. “We need to operate clusters of satellites in tight formation to get enough coherent compute to run AI models efficiently,” Nicolls said. “A cluster will be 10-ish satellites connected with 10 terabits or so of bandwidth between them, and interconnected to the broader constellation.”
That is the most specific detail SpaceX has given on how Starmind will be built. Instead of a million independent servers, the network would work as tightly packed groups of about 10 satellites acting as one compute unit, with Starlink’s laser links carrying results back to Earth.
There is a bright and exciting future for humanity ahead – and space is fundamental to that future.
To achieve this, space safety must be done right. We encourage every operator to not only share ephemeris data proactively the same way Starlink already does, but to also adopt the high standards of space safety that SpaceX and Starlink use every day → https://t.co/QizAkQZvEm
— Starlink (@Starlink) October 6, 2026
Packing satellites that close together, at that scale, makes collision avoidance the central problem, and most of the Space Safety page is aimed at other operators. SpaceX said Starlink encountered collision risks with about 650 unique maneuvering third party satellites in 2026, and only about half of them shared data. Over six months, Starlink recorded roughly 164,000 more collision risks where the closest approach came within four hours of an unannounced maneuver.
Some operators keep maneuver plans private over proprietary concerns, while others cannot get government permission to share them. SpaceX called those policies “counterproductive,” saying they “largely only serve to create preventable collision risk between satellites.” Starlink is also offering a free ephemeris sharing and screening platform that returns risk results within a minute, backed by its Stargaze network of 30,000 optical sensors.
The push comes as the Starmind application draws opposition from astronomers and environmental groups. In a September filing with the FCC, SpaceX said each Starmind satellite could weigh up to 4,000 kg, nearly seven times the mass of a Starlink V2 Mini. Musk has brushed off crowding concerns before, telling viewers in June that “space is enormous” and that SpaceX already knows how to run very large constellations safely.
SpaceX’s Starmind page says its Gigasat factory in Bastrop, Texas, is designed to produce AI satellites at scale, with deployment of thousands of units starting as soon as late 2027.