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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News
Tesla AI and Autopilot VP hints that Robovan will have RV conversions
Tesla’s vice president of AI and Autopilot software, Ashok Elluswamy, hinted at the linitiative in a reply to Y Combinator CEO Garry Tan.
It appears that Tesla is indeed considering an RV in its future pipeline, though the vehicle that would be converted for the purpose would be quite interesting. This is, at least, as per recent comments by a Tesla executive on social media platform X.
Robovan as an RV
Tesla’s vice president of AI and Autopilot software, Ashok Elluswamy, hinted at the linitiative in a reply to Y Combinator CEO Garry Tan, who called for a startup to build RVs with Full Self-Driving capabilities. In his reply, Elluswamy simply stated “On it,” while including a photo of Tesla’s autonomous 20-seat people mover.
Tesla unveiled the Robovan in October 2024 at the “We, Robot” event. The vehicle lacks a steering wheel and features a low floor for spacious interiors. The vehicle, while eclipsed by the Cybercab in news headlines, still captured the imagination of many, as hinted at by X users posting AI-generated images of Robovan RV conversions with beds, kitchens and panoramic windows on social media platforms. One such render by Tesla enthusiast Mark Anthony reached over 300,000 views on X.
Elon Musk on the Robovan
Elon Musk addressed the Robovan’s low profile in October 2024, stating the van uses automatic load-leveling suspension that raises or lowers based on road conditions. The system maintains the futuristic look while handling uneven pavement, Musk wrote on X. The CEO also stated that the Robovan is designed to be very airy inside, which would be great for an RV.
“The view from the inside is one of extreme openness, with visibility in all directions, although it may appear otherwise from the outside. The unusually low ground clearance is achieved by having an automatic load-leveling suspension that raises or lowers, based on smooth or bumpy road conditions,” Musk stated.
-->Elluswamy’s response on X suggests that Tesla is considering a Robovan RV conversion, though it would be interesting to see how the company will make the vehicle capable of reaching campsites. The Robovan has a very low ground clearance, after all, and campsites tend to be in unpaved areas.
Tesla recently released Full Self-Driving (FSD) v14.2.1, its latest version, but the tinkering with Speed Profiles has perhaps gone too far.
We try to keep it as real as possible with Full Self-Driving operation, and we are well aware that with the new versions, some things get better, but others get worse. It is all part of the process with FSD, and refinements are usually available within a week or so.
However, the latest v14.2.1 update has brought out some major complaints with Speed Profiles, at least on my end. It seems the adjustments have gone a tad too far, and there is a sizeable gap between Profiles that are next to one another.
Tesla FSD v14.2.1 first impressions:
✅ Smooth, stress-free highway operation
✅ Speed Profiles are refined — Hurry seems to be limited to 10 MPH over on highways. Switching from Mad Max to Hurry results in an abrupt braking pattern. Nothing of concern but do feel as if Speed…— TESLARATI (@Teslarati) November 29, 2025
The gap is so large that changing between them presents a bit of an unwelcome and drastic reduction in speed, which is perhaps a tad too fast for my liking. Additionally, Speed Profiles seem to have a set Speed Limit offset, which makes it less functional in live traffic situations.
Before I go any further, I’d like to remind everyone reading this that what I am about to write is purely my opinion; it is not right or wrong, or how everyone might feel. I am well aware that driving behaviors are widely subjective; what is acceptable to one might be unacceptable to another.
Speed Profiles are ‘Set’ to a Speed
From what I’ve experienced on v14.2.1, Tesla has chosen to go with somewhat of a preset max speed for each Speed Profile. With ‘Hurry,’ it appears to be 10 MPH over the speed limit, and it will not go even a single MPH faster than that. In a 55 MPH zone, it will only travel 65 MPH. Meanwhile, ‘Standard’ seems to be fixed at between 4-5 MPH over.
This is sort of a tough thing to have fixed, in my opinion. The speed at which the car travels should not be fixed; it should be more dependent on how traffic around it is traveling.
It almost seems as if the Speed Profile chosen should be more of a Behavior Profile. Standard should perform passes only to traffic that is slower than the traffic. If traffic is traveling at 75 MPH in a 65 MPH zone, the car should travel at 75 MPH. It should pass traffic that travels slower than this.
Hurry should be more willing to overtake cars, travel more than 10 MPH over the limit, and act as if someone is in a hurry to get somewhere, hence the name. Setting strict limits on how fast it will travel seems to be a real damper on its capabilities. It did much better in previous versions.
Some Speed Profiles are Too Distant from Others
This is specifically about Hurry and Mad Max, which are neighbors in the Speed Profiles menu. Hurry will only go 10 MPH over the limit, but Mad Max will travel similarly to traffic around it. I’ve seen some people say Mad Max is too slow, but I have not had that opinion when using it.
In a 55 MPH zone during Black Friday and Small Business Saturday, it is not unusual for traffic around me to travel in the low to mid-80s. Mad Max was very suitable for some traffic situations yesterday, especially as cars were traveling very fast. However, sometimes it required me to “gear down” into Hurry, especially as, at times, it would try to pass slower traffic in the right lane, a move I’m not super fond of.
We had some readers also mention this to us:
The abrupt speed reduction when switching to a slower speed profile is definitely an issue that should be improved upon.
— David Klem (@daklem) November 29, 2025
After switching from Mad Max to Hurry, there is a very abrupt drop in speed. It is not violent by any means, but it does shift your body forward, and it seems as if it is a tad drastic and could be refined further.
News
Tesla’s most affordable car is coming to the Netherlands
The trim is expected to launch at €36,990, making it the most affordable Model 3 the Dutch market has seen in years.
Tesla is preparing to introduce the Model 3 Standard to the Netherlands this December, as per information obtained by AutoWeek. The trim is expected to launch at €36,990, making it the most affordable Model 3 the Dutch market has seen in years.
While Tesla has not formally confirmed the vehicle’s arrival, pricing reportedly comes from a reliable source, the publication noted.
Model 3 Standard lands in NL
The U.S. version of the Model 3 Standard provides a clear preview of what Dutch buyers can expect, such as a no-frills configuration that maintains the recognizable Model 3 look without stripping the car down to a bare interior. The panoramic glass roof is still there, the exterior design is unchanged, and Tesla’s central touchscreen-driven cabin layout stays intact.
Cost reductions come from targeted equipment cuts. The American variant uses fewer speakers, lacks ventilated front seats and heated rear seats, and swaps premium materials for cloth and textile-heavy surfaces. Performance is modest compared with the Premium models, with a 0–100 km/h sprint of about six seconds and an estimated WLTP range near 550 kilometers.
Despite the smaller battery and simpler suspension, the Standard maintains the long-distance capability drivers have come to expect in a Tesla.
-->Pricing strategy aligns with Dutch EV demand and taxation shifts
At €36,990, the Model 3 Standard fits neatly into Tesla’s ongoing lineup reshuffle. The current Model 3 RWD has crept toward €42,000, creating space for a more competitive entry-level option, and positioning the new Model 3 Standard comfortably below the €39,990 Model Y Standard.
The timing aligns with rising Dutch demand for affordable EVs as subsidies like SEPP fade and tax advantages for electric cars continue to wind down, EVUpdate noted. Buyers seeking a no-frills EV with solid range are then likely to see the new trim as a compelling alternative.
With the U.S. variant long established and the Model Y Standard already available in the Netherlands, the appearance of an entry-level Model 3 in the Dutch configurator seems like a logical next step.
Tesla AI and Autopilot VP hints that Robovan will have RV conversions
Tesla tinkering with Speed Profiles on FSD v14.2.1 has gone too far
