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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Investor's Corner
Tesla deliveries best Wall Street guesses alongside second-best energy quarter
Tesla (NASDAQ: TSLA) reported strong delivery figures that beat Wall Street guesses, and they were revealed alongside the company’s second-best quarter in terms of energy deployments ever.
Tesla announced this morning that it delivered 486,532 cars in Q3, while producing 464,391, exceeding analyst consensus, which sat around 462,000 units.
Meanwhile, Tesla reported 13.7 GWh of energy storage deployed for the quarter. That’s the second-best quarter Tesla has ever reported on that side of things.
🚨 Tesla delivered 486,532 vehicles in Q3, beating expectations at 464,391.
Big Q from the Tesla team, also 13.7 GWh of energy was deployed. pic.twitter.com/olioLWgG7a
— TESLARATI (@Teslarati) October 2, 2026
Vehicle Deliveries
Deliveries were strong, and it was another quarter when Tesla had the opportunity to outshine the Wall Street pundits who are quick to criticize and slow to give credit. Tesla saw a slight decrease in deliveries compared to Q3 2025, but Tesla still had the $7,500 EV Tax Credit to use to help incentivize consumers to pick an EV.
A small decrease of 2.1 percent is pretty telling because it shows Tesla does not need massive federal credits to convince consumers to purchase its vehicles.
It was also the company’s third-best performance all-time in terms of deliveries, trailing that of Q3 2025 with 497,099 deliveries and Q4 2024, when the company handed over 495,570 cars.
We reported several days ago that Tesla Showrooms across the United States were completely bare of inventory or unclaimed units. Many locations also removed Demo Drive units, which had been bought by customers looking to take delivery sooner.
Tesla showrooms picked clean ahead of Q3 end as demand looks strong
Energy Generation
Tesla’s Energy Generation performance in Q3 was also very strong, as the company deployed 13.7 GWh of energy storage over the past three months. The only quarter when Tesla reported stronger energy deployment figures was Q4 2025, when 14.2 GWh of energy storage was deployed.
Tesla’s Q3 performance in energy generation has continued to grow each quarter, with the company increasing its deployments by ten-fold since Q3 2021, when just 1.3 GWh was deployed.
It is also nearly double what it was in Q3 2024, when the company reported 6.9 GWh. This is one of Tesla’s quickest-growing divisions, and it flies under the radar with fans and analysts, as many are focused on self-driving or the vehicles themselves.
Tesla Stock
Shares rose 5.07 percent to $372.06 at just after 10 a.m. on the East Coast. This is a rarity for Tesla after a strong delivery report, as positive news usually brings the stock down. Many quarters with extremely robust delivery reports have not been as kind to the Teslanaires of the world.
Lifestyle
Tesla’s newest feature lets you floor it out of a Supercharger while plugged in
Tesla’s new Emergency Drive Away feature lets owners flee a Supercharger while still plugged in.
Tesla has given drivers a way to escape while a vehicle is plugged-in at a Supercharger, in the event of an emergency. The company’s charging team announced a new feature on X called Emergency Drive Away, which lets a driver shift into Drive and pull away while the charging cable is still connected to the car.
Until now, a Tesla would not leave Park with a charge cable plugged in. Drivers had to release the latch from the touchscreen, the Tesla app, or the button on the charge handle, then wait for the port to let go. Emergency Drive Away removes that lockout, but Tesla is clear that it comes at a cost. “Use of this feature will damage your vehicle and the Supercharger,” the company wrote, adding that the function is meant for emergencies only and that deliberate misuse will lead to “additional penalties.” Tesla did not say what those penalties are.
Emergency Drive Away lets you shift into Drive while still plugged into a Supercharger pic.twitter.com/40GSzyP4lG
— Tesla Charging (@TeslaCharging) October 1, 2026
The in-car prompt is just as direct, with the warning reading: “Driving with the cable connected will cause damage to your vehicle and the Supercharger. Short camera recordings will be shared with Tesla.” That footage gives Tesla a way to separate a real emergency from someone who simply did not want to wait for the latch.
The feature requires software update 2026.38.3, and Tesla said in replies to owners that it works at every Supercharger in the United States without new stall hardware. Model S and Model X vehicles built before 2021 are not supported, and the company says the feature applies to U.S. Superchargers “for now,” leaving Canada and other markets out at launch.
Tesla Supercharger argument leads to tragic shooting incident
Tesla did not tie the announcement to any specific event, but it arrives two months after a gunman opened fire at an In-N-Out in Twin Falls, Idaho, on August 1, targeting three people in two Teslas at the neighboring Supercharger. One of them, a 66 year old man from Salt Lake City, was killed. Superchargers have been the scene of violence before, including a fatal shooting at a station near Denver in 2023.
In the weeks after Twin Falls, owners pushed Tesla for a native way to escape a stall, and many pointed back to EVject, the aftermarket breakaway connector Tesla sued in 2024 over claims it lacked overtemperature protection. The two companies later reached an agreement that led EVject to recall its earlier connectors in favor of a version with thermal sensors.
Our mission has always been about providing peace of mind and eliminating sitting duck scenarios.
We patented the built-in breakaway charger tip on Feb 15, 2023. Awarded Jan 30, 2024. Then shared the designs with @TeslaCharging
Thank you @Tesla for rolling out a solution. This… https://t.co/djOzswLw9N
— EVject (@EVject) October 2, 2026
Elon Musk
Why Tesla Roadster unveiling delay might have nothing to do with it flying
Tesla announced on Monday that the Roadster event scheduled for today would be postponed due to the need for it to be held outside.
Less than 24 hours later, CEO Elon Musk broadened that by stating it was due to high winds, immediately sending everyone into a frenzy over the Roadster’s potential ability to fly.
And realistically, it could definitely have to do with it flying, hovering, or hopping; whatever Tesla has in mind for this demonstration could not be impacted by wind. However, it might have nothing to do with the vehicle flying whatsoever, and instead could be a simple precaution, as the Roadster is a very unique vehicle with some already official specs that are just mind-blowing.
Tesla will very, very likely be showcasing both the acceleration rate and potentially even a top speed demo at the event in Waco. Both of these demonstrations, performed with a vehicle that has such incredibly fast metrics, could easily be impacted by wind as well.
Tesla Roadster event requires restricted airspace, and the FAA obliges
Top Speed Demo
At high speeds, aerodynamic forces are already overwhelmingly present. A crosswind or sudden gust adds a layer of sideways force that the tires must counter with slip angle. On a short demo course, that force can shove the car off the intended line, especially in a light car with a low frontal area and little mass to resist the push.
Electric cars, due to their battery packs, have an advantage of an extremely low center of gravity, giving them extra stability. However, the speeds at which the Roadster could travel at the demo could spell some issues if crosswinds are present.
Gusts are worse than a steady wind because the load changes faster than a driver can smoothly correct. That shows up as weaving or a late correction. Headwinds and tailwinds can also spell disaster. Headwinds cut a measured top speed but raise the power needed to get there or maintain it. Meanwhile, a tailwind can inflate the top speed, and downforce issues could become more noticeable.
Wind also loads the body unevenly. A low car can feel light on the upwind side or see a sudden change in downforce if the gust hits a wing or diffuser at an angle. Tire temperature and pressure might stay near a normal level, but lateral grip can be lost as the vehicle is spent fighting the wind.
Acceleration Demo
Launch and 0-60 MPH runs are shorter, so the car spends less time exposed to forces that could cause things to go awry. However, the first second is very sensitive, as a crosswind at launch could yaw the car before speed builds and prior to aerodynamic impact being too great. The driver will be required to correct traction control or manage how much the wheels are spinning, which will likely be corrected automatically by some sort of traction control system within the Roadster (we are fairly certain Tesla will implement something brilliant with it).
These things could cause an unstable run.
A headwind would increase drag as speed rises, while a tailwind would do the opposite. Meanwhile, surface effects, like wind-driven dust, light debris, or even rain, could reduce grip at the exact moment the tires are asked for peak longitudinal force. Standing water plus a crosswind is a common reason an acceleration attempt might be scrapped.
Flying or Not
No matter what Tesla has in store for the Roadster, waiting for ideal conditions is a great idea. People who follow and support the company, along with the engineers involved in the Roadster program, have been waiting nine years since the last unveiling for this moment. Everything should be ideal.
Some speculate that it’s just not ready, and that’s ridiculous. Why would Tesla even schedule the event — albeit prematurely — after nine years if it was not ready? Why would they jump the gun now?
We were all excited for today, but it truly is the most ideal thing in the world to wait two more weeks so everything, including the weather, can be perfect. The delay is simply worth it. But Tesla, seriously, make this the last one.