News
Tesla Model S Plaid battery pack shows that 18650 cell innovations are not over yet
A picture of the Tesla Model S Plaid’s 18650 battery pack with its modules visible was recently shared online. The image hinted that Tesla is still in the process of optimizing and innovating its 18650 battery technology, despite the cells being quite a bit long in the tooth.
Tesla is constantly trying to improve its battery technology, which has led to the development of the company’s highly-anticipated 4680 cells. The 4680 cells are expected to be used in vehicles that require a lot of power such as the Semi, Cybertruck, and new Roadster. Amidst the ongoing supply chain challenges and delays in the mass production of 4680 cells from Tesla’s Kato Road facility, however, the company noted that the Model S Plaid, its current flagship sedan, will maintain its use of 18650 batteries.
According to Redditor u/punx, who posted the picture, the Model S Plaid’s battery pack features five large modules, packed to the brim with Panasonic’s 18650 cells. The Reddit user confirmed the cells were 18650 with measurements proving they were 18mm in diameter and 65mm in length. Previous iterations of the Model S have battery packs with as many as 16 individual modules.
A decrease in the number of modules in the Model S Plaid’s battery means fewer parts for the vehicle’s pack, resulting in lower production costs for Tesla. Lowering production costs for its vehicles is a key priority for the company. At the 2021 Annual Shareholders Meeting, Elon Musk mentioned that Tesla has been making a lot of progress in cost reduction, despite the average selling price going down due to the lower prices of vehicles like the Model 3 and Model Y.
“We managed to still do decently well on a gross margin. So, you know, getting the average price down and gross margin up is very difficult,” Musk pointed out. “But we’ve managed to do that. Our goal is really to make the cars as affordable as possible.”
The Model S Plaid (and perhaps the Model X Plaid) might be the last vehicles in Tesla’s lineup that would use 18650 cells. With Tesla focusing its efforts to master the mass production of its 4680 cells — which are more powerful and cheaper to produce — it would not be a surprise if future iterations of the flagship sedan and SUV are fitted with 4680 structural batteries. The 18650 cells are showing their age, after all, as Tesla has been using them since the days of the original Roadster.
If Tesla does utilize its 4680 cells for the Model S and Model X, the vehicles would likely be equipped with nickel-based batteries. The Tesla CEO has previously explained that the supply chain goes all the way back to raw materials like lithium and nickel, which are used to develop the company’s battery cells. During the last earnings call, Elon Musk mulled over the idea of Tesla consolidating its battery offerings down to 2 or 3 form factors, one nickel-based for high-powered vehicles like the Semi and the other iron-based for mass-produced cars like the Model 3.
“So right now, we kind of have the Baskin Robbins of batteries situation, where there’s so many formats and so many chemistries, that it’s like we’ve got like 36 flavors of battery at this point,” Musk said.
“This results in an engineering drag coefficient where each variants of cell chemistry and format requires as certain amount of engineering to maintain it and troubleshoot. And this inhibits our forward progress. So it is going to be important to consolidate to maybe—ideally two form factors, maybe three, but ideally two. And then just one nickel chemistry and one iron chemistry, so we don’t have to troubleshoot so many different variants,” he said.
With Tesla likely retiring its 18650 cells in the future, the Model S Plaid’s five-module battery pack could be seen as one of the final iterations of the technology that the company quite literally used to build its empire. And considering that the 18650 cells are being used in the Model S Plaid, there is no better swan song for the humble batteries.
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A Tesla Semi caught fire in Hayward, California, which caused both directions of traffic to shut down for hours before being completely reopened early on Wednesday, the California Highway Patrol said.
The fire occurred just after 5:30 local time in Hayward on Tuesday, as the Semi caught fire in the southbound lanes of I-880 before CHP officials made the decision to shut down both lanes of traffic due to potential risks from hazardous chemical smoke.
🚨 A Tesla Semi reportedly caught fire, with California Highway Patrol confirming. The Semi was on I-880 SB
An estimated 5,000 to 7,000 semi-truck and large commercial vehicle fires occur on U.S. roadways every year
— TESLARATI (@Teslarati) October 28, 2026
The cause of the fire is currently unknown, as neither Tesla nor the CHP have not determined a cause.
However, some images taken before the Semi was completely destroyed by the fire seem to indicate this might have been an older unit, as it appears to be one of the designs that Tesla shipped as part of its pilot program, before revising it and starting mass production just a month ago.
@Tslachan From on of the videos looks like it’s an old Semi (not the refresh version that recently started production) https://t.co/KzwmR2kXow
— Area Under The Curve 🎗️ (@AreaUnderCurve) October 28, 2026
At the time of publication, CHP had not returned our request for a comment for additional details, including the Semi involved and any potential collaboration on an investigation between the CHP and Tesla. We will update this story when we hear back from them.
The southbound lanes were reopened at 3:30 a.m. on Wednesday, with the northbound lanes opening last night a few hours after the fire began. The CHP did state that the lithium batteries were “incredibly difficult to extinguish,” according to NBC Bay Area.
The truck’s driver said that the Semi caught fire, but he did not have an explanation.
An estimated 5,000 to 7,000 semi-truck and large commercial vehicle fires occur on U.S. roadways every year.
Tesla’s launch of the “Emergency Drive Away” function a few months back offered owners a safe option to evacuate an area if they were in reasonable danger. The function finally got its first use in the real world, but it appears it was by mistake.
A video shared by u/Joshalander in the r/TeslaLounge subreddit recorded the instance from his vehicle and said the incident took place in Austin this past weekend during the city’s F1 Race.
“Was charging around 6 AM this past Sunday in Austin before heading to the F1 race and heard a pop. Looked over and saw the new emergency drive-away feature in action. Genuinely felt bad for the dude when he got out and realized what happened, since he looked exhausted and only seemed to half-read the prompts.”
🚨 Here’s the first look at Tesla’s Emergency Drive Away function in action:
Apparently this driver accidentally enabled it and drove forward; you can see the Supercharger pull with the car.
Tesla said previously this would cost up to $25k if not used properly. https://t.co/B4qQRrsO6B
— TESLARATI (@Teslarati) October 28, 2026
Emergency Drive Away unlatches the Supercharger connector from the vehicle, but still causes damage to both the car and the Supercharger. Tesla has said that it will cost up to $25,000 in repairs to have everything fixed back to normal.
Additionally, the company said that if it were not used in an emergency situation, the driver of the vehicle who activated the Emergency Drive Away feature would be responsible for all repair costs.
Tesla constitutes the following situations as reasonable justifications for activating the feature:
- You face an immediate threat to your life or personal safety.
- You must leave the area immediately.
- Exiting the vehicle is unsafe.
- Unplugging the charge connector would unreasonably delay your departure or expose you to a risk to your personal safety.
After using the feature, Tesla requires the driver to schedule Service so the car can be inspected.
News
Tesla’s Cybercab battery design could make robotaxis even cheaper
Tesla built the Cybercab’s battery pack with spare room for a future switch to LFP.
Tesla built the Cybercab’s battery pack with empty space inside it on purpose, and the reason points to a cheaper robotaxi down the road.
Robert Sumpf, Tesla’s director of mechanical design engineering for battery modules and packs, said the extra room beside and beneath the Cybercab’s modules was left there so the company can move to lithium iron phosphate cells later. “So, we protected this pack to go to an even lower energy dense chemistry as we scale and need to bring LFP into the platform,” Sumpf said in a Cybercab deep dive with Munro Live.
The Cybercab runs on Tesla’s own 4680 cells with a nickel chemistry today. LFP cells store less energy for their size, so a straight swap would cut range. The reserved space lets Tesla add more LFP cells to make up the difference. In return, Tesla would get cells that cost less, run cooler and survive more charge cycles. LFP became the most used EV battery chemistry in the world last year.
Not all of that room was planned for a chemistry change. Lars Moravy, Tesla’s Vice President of Vehicle Engineering, said part of it exists because “we didn’t need as many batteries as we thought we did.” Tesla told Sandy Munro in early 2025 that it was targeting a Cybercab pack under 50 kWh with close to 300 miles of range.
The pack also breaks from the structural design Tesla used in some Model Y and Cybertruck builds. Instead of potting hundreds of cells into one block, the Cybercab uses four separate, individually sealed modules, so a bad module can be replaced without scrapping the whole pack. Sumpf was blunt about the older approach, giving the Model Y structural battery “a grade D” because it was hard to build and nearly impossible to repair. He estimated a fully structural pack gains about 10% more cell volume, but said “the issue is the service cost.”
That cost matters more for a car that rarely sits parked. Cybercab chief engineer Eric Earley said replacing an entire pack “before half a million miles is a killer on cost,” which is why remanufacturing and serviceability were built into the design from the start.
The same Munro Live tour produced Moravy’s admission that the Cybercab line at Giga Texas is now outpacing Robotaxi deployments, along with a look at the robotaxi’s unorthodox paint process. Tesla is aiming to deliver the first Cybercabs to outside customers by the end of 2026, though Elon Musk has said the vast majority will stay owned by Tesla and run as a transport service.
Sumpf did not give a date for an LFP version, name a cell supplier or say how a chemistry change would affect range. For now, the 4680 cars keep piling up: Texas DMV records from Tuesday list 544 Cybercabs authorized for Tesla’s Robotaxi fleet, more than the 507 Model Ys on the same roster for the first time.
Tesla Semi catches fire in California: what we know
Tesla’s ‘Emergency Drive Away’ function gets its first use in the real world
