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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Elon Musk
Tesla Full Self-Driving’s newest behavior is the perfect answer to aggressive cars
According to a recent video, it now appears the suite will automatically pull over if there is a tailgater on your bumper, the most ideal solution for when a driver is riding your bumper.
Tesla Full Self-Driving appears to have a new behavior that is the perfect answer to aggressive drivers.
According to a recent video, it now appears the suite will automatically pull over if there is a tailgater on your bumper, the most ideal solution for when a driver is riding your bumper.
With FSD’s constantly-changing Speed Profiles, it seems as if this solution could help eliminate the need to tinker with driving modes from the person in the driver’s seat. This tends to be one of my biggest complaints from FSD at times.
A video posted on X shows a Tesla on Full Self-Driving pulling over to the shoulder on windy, wet roads after another car seemed to be following it quite aggressively. The car looks to have automatically sensed that the vehicle behind it was in a bit of a hurry, so FSD determined that pulling over and letting it by was the best idea:
Tesla appears to be implementing some sort of feature that will now pull over if someone is tailgating you to let the car by
Really cool feature, definitely get a lot of this from those who think they drive race cars
— TESLARATI (@Teslarati) February 26, 2026
We can see from the clip that there was no human intervention to pull over to the side, as the driver’s hands are stationary and never interfere with the turn signal stalk.
This can be used to override some of the decisions FSD makes, and is a great way to get things back on track if the semi-autonomous functionality tries to do something that is either unneeded or not included in the routing on the in-car Nav.
FSD tends to move over for faster traffic on the interstate when there are multiple lanes. On two-lane highways, it will pass slower cars using the left lane. When faster traffic is behind a Tesla on FSD, the vehicle will move back over to the right lane, the correct behavior in a scenario like this.
Perhaps one of my biggest complaints at times with Full Self-Driving, especially from version to version, is how much tinkering Tesla does with Speed Profiles. One minute, they’re suitable for driving on local roads, the next, they’re either too fast or too slow.
When they are too slow, most of us just shift up into a faster setting, but at times, even that’s not enough, see below:
What has happened to Mad Max?
At one point it was going 32 in a 35. Traffic ahead had pulled away considerably https://t.co/bjKvaMVTNX pic.twitter.com/aaZSWmLu5v
— TESLARATI (@Teslarati) January 24, 2026
There are times when it feels like it would be suitable for the car to just pull over and let the vehicle that is traveling behind pass. This, at least up until this point, it appears, was something that required human intervention.
Now, it looks like Tesla is trying to get FSD to a point where it just knows that it should probably get out of the way.
Elon Musk
Tesla Megapack powers $1.1B AI data center project in Brazil
By integrating Tesla’s Megapack systems, the facility will function not only as a major power consumer but also as a grid-supporting asset.
Tesla’s Megapack battery systems will be deployed as part of a 400MW AI data center campus in Uberlândia, Brazil. The initiative is described as one of Latin America’s largest AI infrastructure projects.
The project is being led by RT-One, which confirmed that the facility will integrate Tesla Megapack battery energy storage systems (BESS) as part of a broader industrial alliance that includes Hitachi Energy, Siemens, ABB, HIMOINSA, and Schneider Electric. The project is backed by more than R$6 billion (approximately $1.1 billion) in private capital.
According to RT-One, the data center is designed to operate on 100% renewable energy while also reinforcing regional grid stability.
“Brazil generates abundant energy, particularly from renewable sources such as solar and wind. However, high renewable penetration can create grid stability challenges,” RT-One President Fernando Palamone noted in a post on LinkedIn. “Managing this imbalance is one of the country’s growing infrastructure priorities.”
By integrating Tesla’s Megapack systems, the facility will function not only as a major power consumer but also as a grid-supporting asset.
“The facility will be capable of absorbing excess electricity when supply is high and providing stabilization services when the grid requires additional support. This approach enhances resilience, improves reliability, and contributes to a more efficient use of renewable generation,” Palamone added.
The model mirrors approaches used in energy-intensive regions such as California and Texas, where large battery systems help manage fluctuations tied to renewable energy generation.
The RT-One President recently visited Tesla’s Megafactory in Lathrop, California, where Megapacks are produced, as part of establishing the partnership. He thanked the Tesla team, including Marcel Dall Pai, Nicholas Reale, and Sean Jones, for supporting the collaboration in his LinkedIn post.
Elon Musk
Starlink powers Europe’s first satellite-to-phone service with O2 partnership
The service initially supports text messaging along with apps such as WhatsApp, Facebook Messenger, Google Maps and weather tools.
Starlink is now powering Europe’s first commercial satellite-to-smartphone service, as Virgin Media O2 launches a space-based mobile data offering across the UK.
The new O2 Satellite service uses Starlink’s low-Earth orbit network to connect regular smartphones in areas without terrestrial coverage, expanding O2’s reach from 89% to 95% of Britain’s landmass.
Under the rollout, compatible Samsung devices automatically connect to Starlink satellites when users move beyond traditional mobile coverage, according to Reuters.
The service initially supports text messaging along with apps such as WhatsApp, Facebook Messenger, Google Maps and weather tools. O2 is pricing the add-on at £3 per month.
By leveraging Starlink’s satellite infrastructure, O2 can deliver connectivity in remote and rural regions without building additional ground towers. The move represents another step in Starlink’s push beyond fixed broadband and into direct-to-device mobile services.
Virgin Media O2 chief executive Lutz Schuler shared his thoughts about the Starlink partnership. “By launching O2 Satellite, we’ve become the first operator in Europe to launch a space-based mobile data service that, overnight, has brought new mobile coverage to an area around two-thirds the size of Wales for the first time,” he said.
Satellite-based mobile connectivity is gaining traction globally. In the U.S., T-Mobile has launched a similar satellite-to-cell offering. Meanwhile, Vodafone has conducted satellite video call tests through its partnership with AST SpaceMobile last year.
For Starlink, the O2 agreement highlights how its network is increasingly being integrated into national telecom systems, enabling standard smartphones to connect directly to satellites without specialized hardware.
Tesla Full Self-Driving’s newest behavior is the perfect answer to aggressive cars
Tesla Megapack powers $1.1B AI data center project in Brazil
