News
University of Michigan uses recycled Kevlar fiber to solve lithium-sulfur battery life cycle issues
The University of Michigan Chemical Sciences and Engineering team, led by Professor Nicholas Kotov, has developed a “new biologically inspired battery membrane” with recycled Kevlar fibers that could quintuple electric vehicle ranges and have a lifespan of 1,000 cycles.
The Ann Arbor, Michigan research facility is one of the best in the world, and Kotov, whose research focuses on the development of biomimetic nanocomposites, the self-assembly of nanoparticles, and chiral nanostructures, has worked to change the narrative on lithium-sulfur cells. “There are a number of reports claiming several hundred cycles for lithium-sulfur batteries, but it is achieved at the expense of other parameters—capacity, charging rate, resilience, and safety,” Kotov said in a press release from the University. “The challenge nowadays is to make a battery that increases the cycling rate from the former 10 cycles to hundreds of cycles and satisfies multiple other requirements including cost.”
Lithium-sulfur batteries can enable five times the capacity of standard lithium-ion cells, which are used in electric vehicles. However, as Professor Kotov mentioned in his quote, the lifespan is significantly decreased due to chemical reactions between molecules. The most common reason for reduced life cycles in lithium-sulfur batteries is dendrites, which are appendages that are designed to receive communications from other cells. These can pierce the membrane of cells, reducing the life span and thus the life cycle of a battery cell.
Another problem is polysulfides, or small molecules of lithium and sulfur, can form and flow to the lithium. They bond and cause blockages, reducing the effectiveness of the membrane. “The membrane is needed to allow lithium ions to flow from the lithium to the sulfur and back—and to block the lithium and sulfur particles, known as lithium polysulfides.”
However, Kevlar, the same material used in bulletproof vests, can stop dendrites from penetrating the membrane using dense aramid fibers found in the material. The cells that Kotov and his team developed use recycled Kevlar fibers. The Kevlar “can enable lithium-sulfur batteries to overcome their Achilles heel of cycle life,” caused by the two previously mentioned reactions between molecules.
An example of the Kevlar system is shown in the images below, as the typical Celgard membrane on the left allows lithium polysulfides to flow through. The Kevlar membrane (right) blocked the polysulfides from traveling through.
“Just half an hour on, the Celgard membrane (left) leaks lithium polysulfides. However, the U-M membrane (right) completely blocks the lithium polysulfides 96 hours later. Image credit: Ahmet Emre, Kotov Lab.” Credit: University of Michigan
“Achieving record levels for multiple parameters for multiple materials properties is what is needed now for car batteries,” Kotov stated. Kotov added that the design of the lithium-sulfur batteries is “nearly perfect” due to its capacity and efficiency reaching theoretical limits. It can also behave more resiliently than lithium-ion cells in warm and cold weather climates, which both have effects on range and efficiency. However, fast charging could reduce the number of lifespans, Kotov added.
Lithium-sulfur batteries could be a good alternative as sulfur is more readily available and abundant than cobalt, which is controversial due to its mining practices. However, automakers like Tesla are reducing cobalt in their batteries vying for other metals, like nickel, instead. Sulfur’s low lifespan and instability, as it changes in size by 78 percent during charging, reduced the possibility of automakers using it in the past, The Independent reported.
The research was funded by the National Science Foundation and the Department of Defense.
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Lifestyle
Tesla wins over Netflix’s Selling Sunset star, who’s now ditching his Bentley
Selling Sunset’s Jason Oppenheim swapped his Bentley for a Tesla and promised ten for employees.
Jason Oppenheim, the luxury real estate broker best known as the star of Netflix’s Selling Sunset, has parked his Bentley for good and moved into a Tesla Model Y, and he says Full Self-Driving (Supervised) is the reason.
Oppenheim, who founded The Oppenheim Group, the Los Angeles brokerage at the center of the show, posted a video to X on Saturday evening that he called “the most important video I’ve ever posted.” In it, he rides from Newport Beach to his firm’s Los Angeles office, a trip he put at roughly an hour and 15 minutes, while FSD handles the drive and parks the car without him touching the wheel or the accelerator. He said he handed the Bentley to his father because he no longer has any use for it.
Tesla shared the clip from its main account on X about two hours later, pulling out the quote that has since spread well beyond the Tesla community:
“[FSD Supervised] is life-changing. I was on the phone with my brother last night, and I made him buy one. He literally bought one while we were talking. I’m buying 10 of my employees a Tesla with FSD. It’s 8x safer than the average driver. There’s nothing more important than the safety of you and your loved ones.”
Oppenheim was candid about why the safety pitch landed with him. He admitted in the video that he is a distracted driver who answers emails and texts behind the wheel, and framed the employee purchases as a way to keep his team off their phones while driving. Elon Musk posted “Tesla FSD feels like magic” less than half an hour after the video went live.
The endorsement lands at a convenient moment for Tesla. The company delivered 486,532 vehicles in Q3, beating Wall Street’s estimates and marking its best quarter ever without the $7,500 federal EV tax credit.
A public service announcement. https://t.co/NYa1IpKwBX
— Jason Oppenheim (@OppenheimJason) October 4, 2026
Tesla FSD has been subscription only in the U.S. since February at $99 per month, and Tesla said in its Q2 update that active subscriptions hit 1.48 million, up 56 percent year over year, with more than 55 percent of new North American deliveries leaving with FSD attached. That attach rate is the figure Ron Baron cited last month when he told CNBC “the time to buy the stock is now.” At current pricing, Oppenheim’s 10 employee cars alone would add $990 a month, or about $11,880 a year, in FSD revenue.
Tesla AI head Ashok Elluswamy said in July that FSD had logged more than 12 billion miles while going roughly twice as far between collisions as manual driving. FSD also remains a supervised system, so Oppenheim and his employees are still required to watch the road, even as Tesla rolls out v14.3.10 with Automatic Collision Evasion, which can steer or brake on its own to avoid a frontal crash.
Elon Musk
Elon Musk follows Trump’s lead, says a SpaceX name change is coming
Elon Musk says SpaceXAI will become SpaceXSI, marking its second rebrand in under three months.
Elon Musk wants to rename his artificial intelligence company again, less than three months after its last rebrand.
In a string of posts on X early Sunday morning, Musk wrote “No more AI,” followed by “SI” and “It’s better.” He then added, “SpaceX is a super intelligence company.” When a user asked whether SpaceXAI could become SpaceXSI, Musk replied, “Yes, we will make that change.”
The posts extend a terminology push that began at the White House last week. On September 29, President Donald Trump signed an executive order directing federal agencies to replace “artificial intelligence” and “AI” with “Super Intelligence” and “SI” on government websites, policy documents and press releases. The same day, Musk sat beside Trump as the heads of the largest AI companies signed a voluntary safety accord, as Teslarati reported. Speaking to reporters afterward, Musk caught himself mid sentence: “I think it is worth highlighting the positive benefits of A.I. … S.I., pardon me.”
Elon Musk and Trump are closer than ever, and Tesla could be the big winner
SpaceXSI would be the third name for the business since February. SpaceX acquired xAI on February 2 in a deal that valued the combined company at $1.25 trillion. In May, Musk said xAI would be dissolved as a separate company, and on July 6 the division adopted the SpaceXAI name and a new logo that placed the xAI letters inside the SpaceX identity.
Musk gave no timeline. He did not say whether SpaceXSI would be a legal name change or a branding update, whether the @SpaceXAI handle on X would change, or how the shift would apply to products like Grok. The company had not issued a formal announcement as of Sunday morning.
The change would reach well beyond a chatbot. SpaceXAI now houses Grok, the X platform, the Colossus training clusters in Memphis and the coding tool Cursor, which SpaceX acquired in August. It also runs the orbital compute effort SpaceX is building around Nvidia hardware, which Musk said during the company’s first earnings call would be exclusive to Nvidia.
It’s unclear if rivals like Anthropic, OpenAI, Google, Meta and Nvidia have plans to also rename their companies or products. OpenAI CEO Sam Altman has continued to say “AI” in public, while Nvidia CEO Jensen Huang has gone partway, describing data centers as “super intelligence factories.”
The rename would also line up SpaceX’s AI branding with the federal government’s language as Musk takes on a new advisory role at the Pentagon, where he is helping lead the Project Meridian study on the future of warfare.
Starlink is launching a new beta path for ordinary property owners and local operators to turn a single Starlink kit into a small shared-access business for passive income.
Under the Starlink for Communities program, a host installs one dish and router setup in a location with nearby demand: an apartment complex, campground, rural crossroads, or event site. Neighbors or local users can buy short-term passes rather than full individual subscriptions, giving the Starlink provider a potential path to passive income.
Hour, day, and week passes cover one device. A month pass covers up to four. Starlink handles account creation, payments, access controls, and the satellite link itself. The host’s role is mainly placement, power, and basic upkeep, with earnings tied to each paid connection.
Big news! SpaceX is introducing a new @Starlink for Communities program that lets you earn money by providing Starlink internet to your neighbors or people nearby, who can pay for access by the hour, day, week, or month.
Neighbors pay for the access they need, while the person… pic.twitter.com/DtOUs0Ekvt
— Sawyer Merritt (@SawyerMerritt) October 1, 2026
The model echoes the passive-income vision long attached to Tesla’s Robotaxi plans, and it seems like it’s something Musk has hinted toward in the past as he believes AI will make the need to work relatively optional. In both cases, the platform owns the hard parts of matching, billing, and network management, while an individual supplies a physical asset that sits idle much of the time.
A Starlink host’s dish can serve multiple nearby users without each household buying and installing its own terminal. A Tesla owner, under the stated Robotaxi concept, would leave a vehicle enrolled in the fleet during unused hours so the car generates rides while the owner is at work or asleep.
Both arrangements convert under-utilized hardware into a revenue stream. They also let the company scale coverage or capacity without owning every endpoint.
Differences are practical. A Starlink kit is a fixed, relatively low-cost terminal whose main constraint is local congestion and line-of-sight. A Tesla Robotaxi is a mobile, high-value vehicle whose earnings depend on demand density, utilization rates, insurance, cleaning, and charging.
Starlink’s program is already accepting host applications in multiple countries and describes the revenue split as ongoing. Tesla’s owner-network version remains more aspirational.
The company currently operates a limited company-controlled robotaxi service in select areas and has solicited interest from fleet buyers for Cybercab vehicles, while private Full Self-Driving owners have not yet been able to dispatch their own cars for paid rides at scale.
Tesla primes Cybercabs for 4K streaming and high bandwidth gaming with Starlink integration
Starlink is a satellite broadband service operated by SpaceX that uses a constellation of low-Earth-orbit satellites to deliver internet to locations where terrestrial broadband is slow, expensive, or absent. It has grown to millions of subscribers worldwide by selling direct residential, mobile, and enterprise terminals, and have become widely available at a wide array at retail locations like Target and Best Buy.
The Communities program extends that reach by letting hosts resell short bursts of capacity to people nearby, while also providing high-speed internet access to those who are simply around a Starlink user.
Tesla wins over Netflix’s Selling Sunset star, who’s now ditching his Bentley
Elon Musk follows Trump’s lead, says a SpaceX name change is coming
