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
SpaceX’s amended S-1 is sparking a major Tesla merger conversation
A single line in SpaceX’s amended S-1 just sent Tesla stock down 5% in one day.
A single line buried in SpaceX’s amended S-1 filing is doing more to move Tesla’s stock price than anything Tesla itself has announced in months. The clause, disclosed as SpaceX prepares for what could be the largest IPO in Wall Street history, states that the company “may issue a significant amount of equity in connection with future transactions.” While this may be seen as boilerplate language in S-1 filings, the historical ties between SpaceX and Tesla, and with Elon Musk reportedly discussing a possible merger with close colleagues, investors are interpreting it as something closer to a signal.
The concern among institutional investors like Gary Black, managing director of The Future Fund, pointed directly to the amended filing on X, saying it “strongly suggests more SPCX equity will be issued,” which could potentially be used to acquire Tesla. He estimated such a deal could be 28% dilutive to Tesla shareholders since SpaceX would likely command a significantly higher valuation multiple. Black added that institutional investors he knows hate the idea of a combination because they prefer pure plays over conglomerates, which he said “nearly always gravitate to the lowest common multiple.”
The Tesla and SpaceX merger everyone is talking about is quietly building
The bull case runs the math differently. Tesla influencer and retail shareholder advocate AleXandra Merz pushed back on what she called a widespread misunderstanding of how merger-of-equals deals actually work. Rather than simply splitting the difference between two market caps, a merger exchange ratio is negotiated based on relative fair market values, meaning the lower valued company typically sees its stock reprice upward toward the deal value.
Under her model, SpaceX enters at a $2.5 trillion valuation and Tesla at $1.6 trillion, producing a combined entity worth $4.1 trillion split evenly between both shareholder groups. That implies Tesla’s side of the deal would be valued at $2.05 trillion, a gain of roughly $450 billion from its current market cap. She cited Dow-DuPont and CBS-Viacom as historical examples of how markets reprice both companies toward the announced exchange ratio after a deal is unveiled.
What does a Merger of Equals mean to Elon’s compensation packages?
Well, it changes everything.
Enjoy https://t.co/uekCldyITw pic.twitter.com/kolq1C9qTu
— AleXandra Merz 🇺🇲 (@TeslaBoomerMama) June 1, 2026
The SpaceX S-1 amendments also revealed just how much financial infrastructure already binds the two companies together. As Teslarati has reported, SpaceX purchased $697 million in Tesla Megapacks, $131 million in Cybertrucks, and the two companies have shared supply chain resources, and semiconductor fabrication plans since well before any merger conversation became public. A retail poll by Tesla influencer Sawyer Merritt is finding that 36% of respondents do not plan to buy SpaceX shares at IPO and 15.3% saying their decision depends on the valuation.
Do you plan on buying @SpaceX stock at its IPO?
— Sawyer Merritt (@SawyerMerritt) June 1, 2026
Whether the merger happens or not, the amended filing is seemingly moving markets and sharpened a debate that is no longer theoretical. SpaceX is weeks away from trading publicly, and Tesla shareholders are now watching every word of every filing for clues about what Musk plans to do next.
Tesla is staging a powerful rebound in Europe. New vehicle registrations surged dramatically across multiple key markets in May 2026, signaling a strong recovery from the challenges of 2025.
Data released this week show double- and triple-digit year-over-year gains in several countries, driven by refreshed Model Y production, supportive policies, high fuel prices, and renewed consumer interest in electric vehicles.
In France, registrations exploded 655 percent to 5,446 vehicles, marking Tesla’s best May performance ever in the country. Norway, a longtime EV stronghold, saw 3,345 new Teslas registered, up 29 percent from May 2025. The company even captured a commanding 21.5 percent market share there, according to Detroit News.
Growth extended to other markets as well. Sweden posted a 71 percent increase to 858 registrations. Denmark jumped 136 percent to 1,750 units, where the Model Y became the top-selling vehicle overall. Spain climbed 113 percent to 1,690 sales, while Portugal soared nearly 350 percent to 1,463.
RELATED:
Tesla Full Self-Driving expansion in Europe continues with new addition
The May results build on a broader turnaround for Tesla in Europe. The company’s sales on the continent had declined sharply in 2025, dropping between 27 and 28 percent amid production shifts, intense competition from Chinese rivals like BYD, and shifting consumer sentiment.
Early 2026 showed signs of life, with registrations rising about 45 percent across Europe in the first quarter and continuing upward momentum through April, up over 46 percent region-wide.
Europe’s overall electrified vehicle market (including BEVs, PHEVs, and hybrids) grew about 21 percent in May, providing a favorable tailwind. Tesla’s gains align with this trend, boosted by government incentives and high fuel costs that make EVs more attractive.
Earlier data from March and April already hinted at strength in Germany, where registrations had surged dramatically in prior months.
Analysts note that while competition remains fierce, Tesla’s refreshed lineup and Europe’s policy support for EVs are helping the company regain ground. The May surge suggests the worst of the 2025 downturn may be behind it, positioning Tesla for stronger performance in the second half of 2026.
This rebound is welcome news for the EV pioneer, demonstrating resilience in a competitive and evolving market. As more data rolls in, investors and industry watchers will be closely monitoring whether this momentum can sustain through the summer and beyond.
Tesla is planning to improve one of the best features on its lineup of cars, a new patent shows. Tesla’s massive glass roof on its premium models is among the coolest additions to the all-electric vehicles, but the design certainly has its complaints, especially from those who live in even slightly warm climates.
Tesla has published a new patent that promises to transform cabin comfort in its electric vehicles, particularly those equipped with the expansive glass roofs.
The document, identified as US20260091643A1 and titled “Airflow Optimization for Cabin Comfort“, addresses that common complaint. Sunlight streaming through windshields and panoramic roofs creates localized hot air pockets near the dashboard and headliner. These pockets generate significant temperature gradients that conventional heating, ventilation, and air conditioning systems struggle to manage evenly.
The exposure to direct sunlight can make the cabin extremely warm, and even after cooling down the interior temperature, combating the continuous stream of sunlight and heat is a challenge. It uses precious energy that is especially pertinent to range and efficiency.
The patent explains how standard dashboard vents push cool air upward, only to entrain warmer air from these stagnant zones and distribute it throughout the occupied cabin space. This process forces the blower to operate at higher speeds, increasing energy consumption and reducing overall efficiency.
In electric vehicles, where every watt impacts driving range, such inefficiencies prove costly.
🚨 THE MODEL Y L IS THE MOST WATCHED EV LAUNCH OF 2026. ITS GLASS ROOF HAS ONE WEAKNESS — AND A PATENT PUBLISHED THIS WEEK SHOWS @TESLA BUILT THE FIX
The Model Y L launched in China and is now arriving in Korea, Japan, and across Asia-Pacific. It also has a glass roof. So does… https://t.co/wr6XnBn1Oc pic.twitter.com/5sYpniXJbU
— SETI Park (@seti_park) April 5, 2026
Research from AAA indicates that air conditioning can diminish range by up to 17 percent under hot conditions. Tesla’s innovation shifts the approach by extracting heat at its source rather than attempting to dilute it after mixing occurs.
Engineers describe a suction HVAC unit connected to dedicated intakes positioned strategically on the upper dashboard surface and within the headliner.
These intakes link to a hot air pocket extraction duct that channels the warmest air directly into the system’s plenum for conditioning. As the blower activates, it simultaneously draws recirculated cabin air and targeted hot pocket air through filters and cooling coils before redistributing conditioned airflow.
It seems somewhat reminiscent of the Tesla heat pump, which aims to combat colder temperatures.
Tesla highlights Model Y’s heat pump innovations in new promotional video
This method reduces entrainment, lowers peak temperatures, and achieves more uniform comfort levels. Testing data reveals that facial temperature gradients drop from 21 degrees Celsius, or 69.8 degrees Fahrenheit, in conventional setups to just 12 degrees Celsius (53.6 degrees F) with the new system. Blower speeds and compressor power requirements decrease appreciably as a result.
The design incorporates smart controls that monitor sunlight intensity and internal temperature distributions in real time. Suction activates selectively only where needed, optimizing energy use without constant high demand. Furthermore, the extraction duct serves a dual purpose.
In the summer months, it pulls hot air inward for cooling; in winter, it reverses to direct warm air outward for rapid windshield defrosting. This versatility allows the reuse of existing hardware with minimal modifications, potentially enabling retrofits in current Tesla fleets.
SpaceX’s amended S-1 is sparking a major Tesla merger conversation
Tesla’s European Comeback: Registrations soar in May as recovery gains momentum
