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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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Tesla has reportedly pushed the unveiling of the Roadster once again, but there are also evidently new details about the event that the company plans to show off.
The Information reported this morning that Tesla will now unveil, for the second time, the next-generation Roadster in August, a further delay from the multiple timeline that the company had previously stated.
The report has not been confirmed or denied by Tesla at any capacity.
It also states the unveiling event will take place in Texas, the same place that Tesla executives revealed in May would be the place of manufacture for the company’s highly-anticipated supercar, which boasts a top speed of over 250 MPH and 650 miles of range, according to its website.
Tesla is also expected to showcase the SpaceX package, which will be used for faster acceleration and potentially hovering capabilities, at the unveiling event, the report states. Musk has always planned for this to happen, but now it seems it is more realistic than ever
The report also states the Roadster unveiling is planned for August pic.twitter.com/By26XZIJzU
— TESLARATI (@Teslarati) June 5, 2026
The Roadster has had its unveiling date and manufacturing date pushed back on many occasions. It was set to start production in 2020, but the COVID-19 pandemic crippled supply chain operations, forcing Tesla to push its timeline back considerably.
However, COVID has been over for some time, and Tesla has still not managed to successfully schedule and execute an unveiling event, which is something fans and enthusiasts, as well as those who have put down a $50,000 deposit, have been waiting for.
The vehicle was close to completion last year, but Musk truly wanted Lars Moravy and Franz von Holzhausen to push the limits of the Roadster. In July of last year, Moravy said:
“Roadster is definitely in development. We did talk about it last Sunday night. We are gearing up for a super cool demo. It’s going to be mind-blowing; We showed Elon some cool demos last week of the tech we’ve been working on, and he got a little excited.”
It is important to note two things: Tesla has not confirmed these details, and the company has regularly pushed these dates back. Until Tesla sends out formal invitations with a concrete date, taking any unveiling event reports with a grain of salt is a good idea.
Tesla is offering a tasty Supercharging incentive on certain Model 3 trims, but the company has officially put a concrete end date on it, so those interested should act fast.
Tesla is offering Free Supercharging for One Year on the Model 3 Premium and Performance trims, the top two offerings of the all-electric sedan. There are three trims of the Model 3 that will have the Free Supercharging offer attached:
- Premium Rear-Wheel-Drive – $42,490
- Premium All-Wheel-Drive – $47,490
- Performance – $54,990
Tesla has now announced that this offer will expire on June 15, giving potential buyers about ten days to take advantage of the incentive.
This could be an additional incentive for car buyers to transition to electric vehicles. Many states are showing gas prices well over $4 per gallon, with the national average currently sitting at $4.22, according to AAA.
A free year of Supercharging miles would allow people to charge and travel for free, other than routine maintenance, which is already incredibly cheap compared to a gas car.
🚨 Tesla is now showing that it’s Free Supercharging offer for Model 3 Premium and Performance trims ends June 15 pic.twitter.com/VCLeddNSj8
— TESLARATI (@Teslarati) June 5, 2026
At Tesla Superchargers, peak rates, meaning prices between 8 a.m. and 10 p.m., average between $0.45 and $0.60. One year of driving at an average of 12,000 miles would cost between $1,000 and $1,500 at $0.50 per kWh. It’s a pretty good deal.
Supercharging prices have also increased recently:
Many of the Superchargers in my area just had their peak rates increased from $0.44 per kWh to $0.49, $0.52, and $0.54 per kWh
If you’re looking to save on your commute/travel for the next year, this Model 3 Free Supercharging incentive might not be a bad idea https://t.co/YDwwl4xxHk pic.twitter.com/DleURW7eqa
— TESLARATI (@Teslarati) June 5, 2026
Tesla has used Free Supercharging to move units in the past, and it’s a great strategy for those who plan to use the car for longer commutes, cross-country drives, or do not have reliable access to home charging.
It should be noted that Tesla recommends that Supercharging be used at a minimum to preserve the life of the battery, as fast-charging is more stressful on the cells.
However, some people might not have an option, so the Free Supercharging incentive could truly be a great reason for many people to charge their cars.
The Supercharging incentive is short-term, and it is pretty rare that Tesla utilizes it, so once this offer is gone, we probably will not see it on the Model 3 for some time.
Ferrari CEO Benedetto Vigna revealed that the Italian automaker’s future will not involve self-driving, a point that echoes that of Tesla CEO Elon Musk’s — sort of.
You might be thinking, “Are you insane? Musk has been so incredibly hellbent on delivering self-driving vehicles to the public, so much so that he has even hinted that Tesla won’t need the ever-popular and widely-requested Model Y L in the U.S.”
However, when it comes to electric supercars with high-performance specs and lofty price tags, Vigna’s stance is exactly what Musk wants for Tesla’s own hypercar project, the Tesla Roadster.
🚨 Tesla Roadster vs. Ferrari Luce
Price – $250,000 vs. $640,000
Horsepower – 1,000+ vs. 1,035
0-60 MPH – 1.1s OR 1.9s vs. 2.4s
Top Speed – 250+ MPH vs. 194 MPH
Range – 620 miles vs. 280 miles https://t.co/uEgswwVLeD pic.twitter.com/XcP58ZRO6Z— TESLARATI (@Teslarati) June 5, 2026
In a new interview with Australian media outlet Drive, Vigna made it clear that Ferrari’s ambitions for the future do not involve autonomy, simply because the company’s cars are not designed for anything but manual, spirited driving.
He said:
“We will not make fully autonomous cars — loud and clear. We want the people to have fun, not the [computer] chips. We want to have a steering wheel and a man or a woman behind the steering wheel. Otherwise, why do you buy a Ferrari?”
This seems to be a reasonable assertion. Ferraris are not made for daily commutes, cross-country road trips, or bumper-to-bumper traffic. They’re made for fast, spirited driving, and many of their buyers will only put a few thousand miles on them throughout their lifetime. True, exciting, fun driving is meant to be done manually.
That is not to say Full Self-Driving or other semi-autonomous suites are not “fun,” but they are meant to take the stress out of driving. They are made for the daily commutes, the rush hour traffic, and the parking lots and garages. It’s made to take the stress out of driving.
Tesla Full Self-Driving attempts 150-mile stress test: the good and the bad
Musk had stated in an interview in early 2026 that the Roadster would also be geared toward fun, manually-controlled driving. On the Moonshots podcast with Peter Diamandis, Musk said about the Roadster:
“This is not a…safety is not the main goal. If you buy a Ferrari, safety is not the number one goal. I say, if safety is your number one goal, do not buy the Roadster…We’ll aspire not to kill anyone in this car. It’ll be the best of the last of the human-driven cars. The best of the last.”
There are cars out there that simply are meant to be driven by humans, and Ferraris and Roadsters are a few of them. Ferrari has no true advantage in developing self-driving; their cars sell at low volumes with high price tags, and their performance specs and engineering are all geared toward spirited driving.
Tesla Roadster unveiling gets pushed again, but new event details emerge
Tesla Model 3 has a tasty Supercharging incentive, but it’s ending soon
