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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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A new Tesla patent that has been granted to the company this week has revealed a potential strategy for solving a major issue that could impact both the Full Self-Driving suite and Optimus.
The patent, which is No. 12,636,684, describes a “Lens Cleaning System,” and was submitted by Tesla in May 2025.
The language in the patent details a lens cleaning system that can dispense fluid and wipe it away with a wiper assembly.
Optimus can see you now… 🤖👁️
The patent for @Tesla_Optimus‘s eye structure just dropped. $TSLA pic.twitter.com/Jac4VhDmKH
— SETI Park (@seti_park) May 26, 2026
This would effectively clean any debris that would potentially impact the visibility of the cameras on Tesla automobiles or Optimus’s camera eyes. Perhaps the most pertinent example is through the Full Self-Driving suite, as debris that can accumulate on the vehicle’s exterior cameras can impact the suite’s ability to operate effectively.
This requires a remedy through manual cleaning, but this patent hints that Tesla could be planning to implement this new technology on its upcoming vehicles.
Interestingly, we have started to see it on some Robotaxi vehicles, and it will likely be included in the Cybercab, especially as that vehicle will enable full autonomy.
Back in January, the first Model Y Robotaxi units were spotted with camera washers on the side repeaters, as the video below shows fluid squirting and rinsing off any debris that is limiting visibility.
🚨 Tesla looks to have installed Camera Washers on the side repeater cameras on Robotaxis in Austin
pic.twitter.com/xemRtDtlRR— TESLARATI (@Teslarati) January 23, 2026
This hardware patent does bring up an interesting question for those of us who own Teslas with AI4 and have been told that our cars will one day be capable of full autonomy: Will this washer be available as a retrofit on already-built cars?
Perhaps the “Lens Cleaning System” patent is a good look at one way Tesla plans to combat one of the most obvious issues of autonomy that utilizes a camera-based system. For Optimus, it could be less needed as it could be manually cleaned by owners. For cars, it seems like a bigger necessity, especially as autonomy nears and Tesla gets close to launching a feature-complete FSD suite.
SpaceX’s Starlink product has just gotten its latest airline adoptee, and the move marks the successful partnership of three of the “Big Four” U.S. airlines.
American Airlines announced on Tuesday that it would utilize Starlink in more than 500 narrowbody aircraft beginning in the first quarter of 2027. These include the Airbus aircraft in its fleet, including the new A321XLR and A321neo.
With the new partnership with American Airlines, Starlink is now present on three of the largest airlines in the country: American, United, and Southwest.
Starlink gets its latest airline adoptee for stable and reliable internet access
Starlink’s VP of Enterprise Sales, Jason Fritch, said:
“We are proud to bring Starlink on board American Airlines, delivering fast and reliable internet to passengers and crew. Whether traveling for leisure or business, Starlink enables a fully connected experience gate to gate, making every flight smoother and more enjoyable.”
Additionally, American Airlines Chief Customer Officer, Heather Garboden, said:
“As a premium global airline, we are continuously seeking out world-class partners like Starlink to deliver what our customers need and want. The addition of Starlink solidifies American as a leading airline in keeping passengers connected in flight.”
Starlink has been on a tear over the past year, as it has continued to be adopted by a wide variety of airlines as a more consistent and reliable way to provide WiFi to its passengers. It has already gained a great reputation among residential users, but its biggest commercial application appears to be how it is being used in the air.
American Airlines will adopt Starlink on more than 500 of its narrowbody aircraft beginning in Q1 2027
“As a premium global airline, we are continuously seeking out world-class partners like Starlink to deliver what our customers need and want,” said American Airlines Chief… pic.twitter.com/XY2wflycc0
— TESLARATI (@Teslarati) May 26, 2026
The only airline of the Big Four not to adopt Starlink thus far is Delta, which chose to opt for the alternative, which is Amazon Leo. CEO Ed Bastian said to Bloomberg that Delta chose Amazon’s product over Starlink’s because “the opportunities, in terms of the improved bandwidth with a much lower price point than what we’ve ever seen from Starlink, will make a big difference.”
Delta will not start installing Amazon Leo until 2028.
“Of course, we expect Starlink will be warning people that we’re going to go with an inferior product,” Bastian said. “But I’m not too worried about partnering with Amazon.”
Tesla Cybertruck’s newest trim level is nearing its first deliveries just a few months after being offered for an incredible deal.
Back in February, Tesla officially launched a new trim of the Cybertruck, the All-Wheel-Drive, starting at just $59,990. It was a lot of truck for the money, especially considering what it offered the Rear-Wheel-Drive variant for last year, which was a total flop.
The $59,990 price that was offered initially was a deal due to its 325-mile range rating, powered tonneau, three bed outlets, Powershare capability, coil springs with adaptive damping for a refined suspension feel, Steer-by-Wire and four-wheel steering, a 6′ x 4′ composite bed, towing capacity of 7,500 pounds, and a powered frunk.
Tesla is now nearing deliveries of this trim, according to watcher Sawyer Merritt, as Tesla has officially started assigning VINs to people who ordered the vehicle initially:
I can confirm that Tesla has officially started assigning VINs to people who initially ordered the $59,990 Cybertruck Dual-Motor AWD, which means first deliveries should start in the coming weeks!
• 325 mile range
• 7,500 lb towing capacity
• 0-60mph: 4.1s
• Bed with… pic.twitter.com/PQwVYbZf6j— Sawyer Merritt (@SawyerMerritt) May 24, 2026
Earlier this month, we reported on units of the trim being spotted outside Gigafactory Texas by Joe Tegtmeyer.
Tesla Giga Texas buzzing as new Cybertruck appears to enter production
This Cybertruck trim was interesting because it was released basically out of nowhere, priced incredibly well, and gathered many orders in a small amount of time. However, CEO Elon Musk noted just days afterward that the vehicle would only be priced at this bargain level for ten days.
Tesla fans were not happy.
Awful way to treat customers – particularly when they already sent out a marketing email announcing the $59,990 truck…with zero mention of it being a limited-time offer.
— Ryan McCaffrey (@DMC_Ryan) February 24, 2026
However, the issues with the pricing strategy have blown over since the February unveiling event, and now that deliveries are near, Tesla fans are anticipating the truck making its way to their driveways soon.
The truck is currently priced at $69,990, and deliveries for new orders are slated for between August and September 2026.
Tesla patent reveals strategy for solving major Full Self-Driving, Optimus issue
SpaceX Starlink gets its latest airline adoptee, grabbing three of the ‘Big Four’
