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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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SpaceX CEO Elon Musk recently confronted worries about orbital data centers and launching satellites in mass quantities in space, as some voiced concerns about crowding.
Musk’s SpaceX plans to combat the issue of needing data centers by launching them into space instead of taking up valuable real estate on Earth. It has been a major point of SpaceX’s future, including its looming IPO, which could be the largest ever.
In a recent interview filmed at SpaceX’s Starlink terminal factory in Bastrop, Texas, Elon Musk directly addressed concerns that deploying large numbers of AI satellites for orbital data centers could crowd Earth’s orbit. His message was straightforward and reassuring: space is vast beyond human intuition.
“Space is really big,” Musk said. “It’s not like space is gonna get crowded. Space is enormous. If you actually look at it relative to the Earth, the satellites are so tiny you can’t even see them.” He emphasized that even zooming in makes a satellite appear large, but from a planetary perspective, they are minuscule specks.
Elon on concerns that AI satellites will crowd space:
“Space is really big. It’s not like space is gonna get crowded. Space is enormous. If you actually look at it relative to the earth, the satellites are so tiny you can’t even see them.” https://t.co/Mvr7NpL25Q pic.twitter.com/5Fi629Rii7
— Sawyer Merritt (@SawyerMerritt) June 8, 2026
Musk pointed to SpaceX’s real-world experience operating roughly 10,000 Starlink satellites as evidence that large constellations can be managed safely. “We’ve got a pretty good idea of how to operate just really large constellations and do it safely,” he noted. SpaceX remains the only operator with meaningful experience at this scale, giving the company unique insight into tight orbital packing without compromising safety
The discussion highlighted SpaceX’s plans for “AI1” satellites—essentially orbiting racks of AI compute powered by massive solar arrays and cooled via radiative panels in space’s vacuum.
These satellites leverage proven Starlink V3 technology, making them simpler to design than communications satellites. A first-generation unit targets around 150 kW peak power, with a 70-meter wingspan for solar panels and radiators. Laser links will connect them to each other and the Starlink network, delivering low-latency access (on the order of a few milliseconds from low-Earth orbit).
FCC accepts SpaceX filing for 1 million orbital data center plan
Musk framed orbital data centers as a practical solution to Earth’s constraints on AI growth. Ground-based facilities face power shortages, water demands for cooling, and grid limitations. In space, constant sunlight (no day-night cycle), vacuum radiative cooling, and abundant solar energy offer clear advantages.
Production will ramp up at an expanded “Gigasat” factory in Bastrop, with solar manufacturing already underway and full AI satellite output expected at reasonable volume by the end of 2027. Starship’s rapid, high-volume launch capability, aiming for multiple flights per hour, will make massive deployment feasible.
Critics sometimes raise risks like space debris or Kessler syndrome, but Musk’s response underscores scale: even a million satellites would represent an imperceptible fraction of available orbital volume when viewed against Earth’s size. SpaceX’s automated collision avoidance and deorbiting designs for Starlink further mitigate concerns.
This vision ties into broader ambitions. Musk sees orbital AI compute as a step toward harnessing more of the Sun’s energy, advancing humanity on the Kardashev scale from a Type 0 civilization toward Type 1 and eventually Type 2. By moving power-hungry data centers off-planet, SpaceX aims to unlock orders-of-magnitude more compute while preserving Earth’s resources.
Musk’s comments should ease public anxiety. With proven operational expertise, incremental engineering, and the immensity of space itself, orbital data centers represent not overcrowding, but smart expansion into the final frontier.
Tesla Full Self-Driving (Supervised) is currently listed as a Level 2 suite in terms of its passenger cars. As its Robotaxi platform continues to move quickly, it has been recognized as a Level 4 ride-sharing program by the State of Texas, as Tesla recently self-certified itself.
However, a Wall Street analyst is arguing that Tesla (NASDAQ: TSLA) has effectively achieved Level 4 autonomy in most conditions in all of its vehicles, drawing on personal experience and data released by the company.
Alex Potter of Piper Sandler said in a note to investors on Wednesday that “Tesla has solved the self-driving puzzle,” pointing to decisions to offer insurance discounts for FSD-enabled policies as a signal of confidence, which is backed up by stellar safety records compared to human driving.
Investing.com initially reported on Potter’s new note.
Additionally, Potter looks at the recent start of Cybercab production at Giga Texas as a potential indication that Tesla is ready to offer some level of unsupervised driving at least in the near future. The Cybercab has no steering wheel or pedals, completely eliminating the ability for human input.
He also sees Tesla’s allocation of “several hundred million USD (if not $1B+)” as confidence internally, seeing as it would be tough to set aside that amount of capital toward a project that the company does not see as relatively near-term.
Forward thinking, especially as Cybercab has no human controls, it would make sense that Tesla is at least close to self-driving. How close is another question.
Tesla has routinely teased that unsupervised FSD is close, but there are still a lot of things it feels as if the company has to roll out some more capability, including unsupervised parking features, known as “Banish,” better operation with regional self-driving performance, and other improvements.
That is not to say that Tesla FSD is super impressive already. It has already completed coast-to-coast drives across the United States and Canada, it routinely takes the stress out of driving for most people, and it has proven through Tesla Safety Reports that it is safer and involved in accidents less frequently than humans.
🚨 These are the first-ever FSD safety statistics out of the Netherlands, showing it was over 3.5x safer than human driving on Dutch roads.
The most recent numbers out of Tesla for North America show:
-Over 5.5 million miles between accidents for Teslas using FSD
-660k miles… https://t.co/XKlRzgSGEh pic.twitter.com/HX6kzh0ZKc— TESLARATI (@Teslarati) June 9, 2026
Even Potter believes it is capable, as he used it to go from Missoula, Montana, to Minneapolis, Minnesota, back in April.
“There’s no substitute for personal experience,” he wrote.
Tesla has finally and officially confirmed that Actually Smart Summon, commonly known as ASS, will make its way to the Cybertruck two and a half years after first deliveries.
The feature, which is part of the Full Self-Driving suite, allows owners of any Tesla to literally summon their vehicle to their location in a parking lot. It is limited by range and speed, especially as there is nobody in the vehicle, but is a great feature to have for rainstorms, busy parking lots, or for injured passengers (I recently used it so I could give my Fiancèe a hand leaving a sports injury doctor after she pulled her calf).
Tesla Summon has been a lifesaver for picking up my Fiancèe as she pulled her calf during a 10-mile race in Philadelphia this past weekend!
It went from one of her least favorite features of the Tesla to one of the most useful:pic.twitter.com/CPs6lTSPA8
— TESLARATI (@Teslarati) May 6, 2026
Summon has been available on every Tesla that is currently available, but the Cybertruck has not had the feature in the two and a half years that customers have been taking deliveries.
There were a few things that Tesla had to work out with Full Self-Driving features, Summon in particular, with the Cybertruck.
Initially, its Steer-by-Wire system handles low-speed maneuvers differently than a typical mechanical steering connection available in the S3XY lineup. This required some additional time of development to allow Tesla to retrain and validate the AI models specifically for the feature within Cybertruck.
Additionally, the overall size and weight of Cybertruck impacted expected dynamics, has an impact on braking distances, and even obstacle avoidance in tighter lots. Tesla prioritized safety over launching the feature ahead of having the utmost confidence in it.
However, the wait is finally over, at least it seems that way. Tesla said that Cybertruck will receive ASS through a Software Update “shortly,” but did not give an explicit date. Tesla has said that Summon is coming in the past, only for it to be delayed yet again.
Summon for Cybertruck rolling out shortly https://t.co/rGli2iHbtL
— Tesla (@Tesla) June 10, 2026
We anticipate that Summon will roll out within the Cybertruck in less than a week, but there are still some reservations about that timing because, ultimately, nobody knows what Tesla will do outside of Tesla. The Spring Update for many came well late, at least a month past the initial rollout wave.
The rollout of Summon to Cybertruck is a great milestone for Tesla, even if it has come later than most would really like to admit. Now that Cybertrucks will be summoned across parking lots, it will be awesome to see reactions to the massive pickup with no driver sitting in the driver’s seat.
SpaceX’s Elon Musk relieves worries about orbital data centers
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