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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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Man credits Grok AI with saving his life after ER missed near-ruptured appendix
The AI flagged some of the man’s symptoms and urged him to return to the ER immediately and demand a CT scan.
A 49-year-old man has stated that xAI’s Grok ended up saving his life when the large language model identified a near-ruptured appendix that his first ER visit dismissed as acid reflux.
After being sent home from the ER, the man asked Grok to analyze his symptoms. The AI flagged some of the man’s symptoms and urged him to return immediately and demand a CT scan. The scan confirmed that something far worse than acid reflux was indeed going on.
Grok spotted what a doctor missed
In a post on Reddit, u/Tykjen noted that for 24 hours straight, he had a constant “razor-blade-level” abdominal pain that forced him into a fetal position. He had no fever or visible signs. He went to the ER, where a doctor pressed his soft belly, prescribed acid blockers, and sent him home.
The acid blockers didn’t work, and the man’s pain remained intense. He then decided to open a year-long chat he had with Grok and listed every detail that he was experiencing. The AI responded quickly. “Grok immediately flagged perforated ulcer or atypical appendicitis, told me the exact red-flag pattern I was describing, and basically said “go back right now and ask for a CT,” the man wrote in his post.
He copied Grok’s reasoning, returned to the ER, and insisted on the scan. The CT scan ultimately showed an inflamed appendix on the verge of rupture. Six hours later, the appendix was out. The man said the pain has completely vanished, and he woke up laughing under anesthesia. He was discharged the next day.
How a late-night conversation with Grok got me to demand the CT scan that saved my life from a ruptured appendix (December 2025)
byu/Tykjen ingrok
AI doctors could very well be welcomed
In the replies to his Reddit post, u/Tykjen further explained that he specifically avoided telling doctors that Grok, an AI, suggested he get a CT scan. “I did not tell them on the second visit that Grok recommended the CT scan. I had to lie. I told them my sister who’s a nurse told me to ask for the scan,” the man wrote.
One commenter noted that the use of AI in medicine will likely be welcomed, stating that “If AI could take doctors’ jobs one day, I will be happy. Doctors just don’t care anymore. It’s all a paycheck.” The Redditor replied with, “Sadly yes. That is what it felt like after the first visit. And the following night could have been my last.”
Elon Musk has been very optimistic about the potential of robots like Tesla Optimus in the medical field. Provided that they are able to achieve human-level articulation in their hands, and Tesla is able to bring down their cost through mass manufacturing, the era of AI-powered medical care could very well be closer than expected.
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Tesla expands Model 3 lineup in Europe with most affordable variant yet
The Model 3 Standard still delivers more than 300 miles of range, potentially making it an attractive option for budget-conscious buyers.
Tesla has introduced a lower-priced Model 3 variant in Europe, expanding the lineup just two months after the vehicle’s U.S. debut. The Model 3 Standard still delivers more than 300 miles (480 km) of range, potentially making it an attractive option for budget-conscious buyers.
Tesla’s pricing strategy
The Model 3 Standard arrives as Tesla contends with declining registrations in several countries across Europe, where sales have not fully offset shifting consumer preferences. Many buyers have turned to options such as Volkswagen’s ID.3 and BYD’s Atto 3, both of which have benefited from aggressive pricing.
By removing select premium finishes and features, Tesla positioned the new Model 3 Standard as an “ultra-low cost of ownership” option of its all-electric sedan. Pricing comes in at €37,970 in Germany, NOK 330,056 in Norway, and SEK 449,990 in Sweden, depending on market. This places the Model 3 Standard well below the “premium” Model 3 trim, which starts at €45,970 in Germany.
Deliveries for the Standard model are expected to begin in the first quarter of 2026, giving Tesla an entry-level foothold in a segment that’s increasingly defined by sub-€40,000 offerings.
Tesla’s affordable vehicle push
The low-cost Model 3 follows October’s launch of a similarly positioned Model Y variant, signaling a broader shift in Tesla’s product strategy. While CEO Elon Musk has moved the company toward AI-driven initiatives such as robotaxis and humanoid robots, lower-priced vehicles remain necessary to support the company’s revenue in the near term.
Reports have indicated that Tesla previously abandoned plans for an all-new $25,000 EV, with the company opting to create cheaper versions of existing platforms instead. Analysts have flagged possible cannibalization of higher-margin models, but the move aims to counter an influx of aggressively priced entrants from China and Europe, many of which sell below $30,000. With the new Model 3 Standard, Tesla is reinforcing its volume strategy in Europe’s increasingly competitive EV landscape.
News
Tesla FSD (Supervised) stuns Germany’s biggest car magazine
FSD Supervised recognized construction zones, braked early for pedestrians, and yielded politely on narrow streets.
Tesla’s upcoming FSD Supervised system, set for a European debut pending regulatory approval, is showing notably refined behavior in real-world testing, including construction zones, pedestrian detection, and lane changes, as per a recent demonstration ride in Berlin.
While the system still required driver oversight, its smooth braking, steering, and decision-making illustrated how far Tesla’s driver-assistance technology has advanced ahead of a potential 2026 rollout.
FSD’s maturity in dense city driving
During the Berlin test ride with Auto Bild, Germany’s largest automotive publication, a Tesla Model 3 running FSD handled complex traffic with minimal intervention, autonomously managing braking, acceleration, steering, and overtaking up to 140 km/h. It recognized construction zones, braked early for pedestrians, and yielded politely on narrow streets.
Only one manual override was required when the system misread a converted one-way route, an example, Tesla stated, of the continuous learning baked into its vision-based architecture.
Robin Hornig of Auto Bild summed up his experience with FSD Supervised with a glowing review of the system. As per the reporter, FSD Supervised already exceeds humans with its all-around vision. “Tesla FSD Supervised sees more than I do. It doesn’t get distracted and never gets tired. I like to think I’m a good driver, but I can’t match this system’s all-around vision. It’s at its best when both work together: my experience and the Tesla’s constant attention,” the journalist wrote.
Tesla FSD in Europe
FSD Supervised is still a driver-assistance system rather than autonomous driving. Still, Auto Bild noted that Tesla’s 360-degree camera suite, constant monitoring, and high computing power mark a sizable leap from earlier iterations. Already active in the U.S., China, and several other regions, the system is currently navigating Europe’s approval pipeline. Tesla has applied for an exemption in the Netherlands, aiming to launch the feature through a free software update as early as February 2026.
What Tesla demonstrated in Berlin mirrors capabilities already common in China and the U.S., where rival automakers have rolled out hands-free or city-navigation systems. Europe, however, remains behind due to a stricter certification environment, though Tesla is currently hard at work pushing for FSD Supervised’s approval in several countries in the region.
Man credits Grok AI with saving his life after ER missed near-ruptured appendix
Tesla expands Model 3 lineup in Europe with most affordable variant yet
