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 expands global FSD (Supervised) testing with Abu Dhabi trials
The program marks the emirate’s first formal testing framework for Tesla’s supervised autonomous driving technology.
Tesla has started its first Full Self-Driving (Supervised) road trials in Abu Dhabi under the oversight of the Integrated Transport Centre, also known as Abu Dhabi Mobility.
The program marks the emirate’s first formal testing framework for Tesla’s supervised autonomous driving technology.
FSD (Supervised) road trials are being conducted with the support of the Smart and Autonomous Systems Council and in coordination with the Legislation Lab at the General Secretariat of the UAE Cabinet.
Dr. Abdulla Hamad AlGhfeli, Acting Director General of the Integrated Transport Centre (Abu Dhabi Mobility), highlighted the agency’s regulatory role in overseeing the FSD (Supervised) tests in a press release.
“The supervision of the Integrated Transport Centre (Abu Dhabi Mobility) over the commencement of Tesla’s advanced autonomous driving technology tests reflects its regulatory and legislative role. These tests represent a qualitative step to evaluate the technology’s performance in a real-world operating environment and to collect the necessary data to verify its readiness before any future expansion in usage.
“Through this organized framework, and in cooperation with strategic partners, we seek to achieve a balance between supporting innovation and encouraging the adoption of smart solutions on one hand and ensuring the safety of road users on the other, in line with the emirate’s direction to develop an advanced, safe, and sustainable transport system,” he said.
Tesla is putting a lot of effort into expanding the rollout of FSD (Supervised) to territories outside in the United States. During a recent interview with Giga Berlin plant manager Andre Thierig, Musk stated that Tesla is looking to secure approval for FSD (Supervised) in the Netherlands this coming March.
“Tesla has the most advanced real-world AI, and hopefully, it will be approved soon in Europe. We’re told by the authorities that March 20th, it’ll be approved in the Netherlands,’ what I was told. Hopefully, that date remains the same. But I think people in Europe are going to be pretty blown away by how good the Tesla car AI is in being able to drive,” Musk stated.
Elon Musk
SpaceX considering confidential IPO filing this March: report
The filing could pave the way for a June listing at a valuation that may exceed $1.75 trillion.
SpaceX is reportedly preparing to confidentially file for an initial public offering (IPO) as soon as March. The filing could pave the way for a June listing at a valuation that may exceed $1.75 trillion, potentially making it the largest IPO in history.
The update was initially reported by Bloomberg News, which cited information shared by people reportedly familiar with the matter.
As per the publication, a confidential filing allows a company to receive regulatory feedback before publicly releasing its financials. Bloomberg’s source, however, noted that the timing of SpaceX’s IPO is still under discussion and plans could change.
SpaceX did not immediately respond to requests for comment.
A March submission would mark the clearest step yet toward bringing Elon Musk’s private space company into public markets. People familiar with the preparations said the offering could raise as much as $50 billion. That would surpass the $29 billion debut of Saudi Aramco in 2019, currently the largest IPO on record.
Major banks including Goldman Sachs Group Inc., JPMorgan Chase & Co., Morgan Stanley, and Bank of America Corp. are reportedly positioned for senior roles in the transaction. SpaceX is also said to be considering a dual-class structure that would allow insiders, including Musk, to retain enhanced voting control.
Satellite communications provider EchoStar Corp., which holds a stake in SpaceX, reportedly saw its shares rise following news of the potential filing.
At a valuation exceeding $1.75 trillion, SpaceX would immediately have a larger market cap than all but five of the companies traded in the S&P 500 index. That figure would place it ahead of Meta Platforms Inc. and Tesla Inc. by market capitalization, trailing only a small group of mega-cap firms such as Apple Inc. and Microsoft Corp.
The scale of the proposed valuation reflects SpaceX’s dominance in orbital launch services and its Starlink satellite network, which serves millions of users globally. The company has also outlined long-term expansion plans tied to higher Starship launch cadence, orbital infrastructure, and lunar development initiatives.
Elon Musk
Elon Musk hints Tesla investors will be rewarded heavily
“Hold onto your Tesla stock. It’s going to be worth a lot, I think. That’s my bet,” Musk said.
Elon Musk recently hinted that he believes Tesla investors will be rewarded heavily if they continue to hold onto their shares, and he reiterated that in a new interview that the company released on its social accounts this week.
Musk is one of the most successful CEOs in the modern era and has mammothed competitors on the Forbes Net Worth List over the past year as his holdings in his various companies have continued to swell.
Tesla investors, especially those who have been holding shares for several years, have also felt substantial gains in their portfolios. Over the past five years, the stock is up over 78 percent. Since February 2019, nearly seven years ago to the day, the stock is up over 1,800 percent.
Musk said in the interview:
“Hold onto your Tesla stock. It’s going to be worth a lot, I think. That’s my bet.”
Elon Musk in new interview: “Hold on to your $TSLA stock. It’s going to be worth a lot, I think. That’s my bet.” pic.twitter.com/cucirBuhq0
— Sawyer Merritt (@SawyerMerritt) February 26, 2026
It’s no secret Musk has been extremely bullish on his own companies, but Tesla in particular, because it is publicly traded.
However, the company has so many amazing projects that have an opportunity to revolutionize their respective industries. There is certainly a path to major growth on Wall Street for Tesla through its various future projects, including Optimus, Cybercab, Semi, and Unsupervised FSD.
- Optimus (Tesla’s humanoid robot): Musk has discussed its potential for tasks like childcare, walking dogs, or assisting elderly parents, positioning it as a massive long-term driver of company value.
- Cybercab (Tesla’s robotaxi/autonomous ride-hailing vehicle): a fully autonomous vehicle geared specifically for Tesla’s ride-sharing ambitions.
- Semi (Tesla’s electric truck, with mentions of expansion, like in Europe): brings Tesla into the commercial logistics sector.
- Unsupervised FSD (Full Self-Driving software achieving full autonomy without human supervision): turns every Tesla owner’s vehicle into a fully-autonomous vehicle upon release
These projects specifically are some of the highest-growth pillars Tesla has ever attempted to develop, especially in Musk’s eyes, as he has said Optimus will be the best-selling product of all-time.
Many analysts agree, but the bullish ones, like Cathie Wood of ARK Invest, are perhaps the one who believes Tesla has incredible potential on Wall Street, predicting a $2,600 price target for 2030, but this is not even including Optimus.
She told Bloomberg last March that she believes that the project will present a potential additive if Tesla can scale faster than anticipated.
Tesla expands global FSD (Supervised) testing with Abu Dhabi trials
SpaceX considering confidential IPO filing this March: report
