

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
Tesla analyst says Musk stock buy should send this signal to investors
“With Musk’s (Tesla stock) purchase, combined with the upward momentum for delivery expectations and robotaxi rollout, we are becoming more bullish.”

Tesla CEO Elon Musk purchased roughly $1 billion in Tesla shares on Friday, and analysts are now breaking down the move as the stock is headed upward.
One of them is William Blair analyst Jed Dorsheimer, who said in a new note to investors on Monday that Musk’s move should send a signal of confidence to stock buyers, especially considering the company’s numerous catalysts that currently exist.
Elon Musk just bought $1 billion in Tesla stock, his biggest purchase ever
Dorsheimer said in the note:
“With Musk’s (Tesla stock) purchase, combined with the upward momentum for delivery expectations and robotaxi rollout, we are becoming more bullish. This purchase is Musk’s first buy since 2020. To us, this sends a strong signal of confidence in the most important part of Tesla’s future business, robotaxi.”
Musk putting an additional $1 billion back into the company in the form of more stock ownership is obviously a huge vote of confidence.
He knows more than anyone about the progress Tesla has made and is making on the Robotaxi platform, as well as the company’s ongoing efforts to solve vehicle autonomy. If he’s buying stock, it is more than likely a good sign.
Tesla has continued to expand its Robotaxi platform in a number of ways. The project has gotten bigger in terms of service area, vehicle fleet, and testing population. Tesla has also recently received a permit to test in Nevada, unlocking the potential to expand into a brand-new state for the company.
In the note, Dorsheimer also touched on Musk’s recent pay package, revealing that William Blair recently met with Tesla’s Board of Directors, who gave the firm some more color on the situation:
“We recently participated in a meeting with Tesla’s board of directors to discuss the details of Musk’s performance package. The board is confident of its position in the Delaware case and anticipates a verdict by end of year. It does not expect a similar situation to occur under new Texas jurisdiction. Musk has the board’s full support, and we expect he’ll get more than enough shareholder support for this to pass with flying colors.”
Tesla stock is up over 6 percent so far today, trading at $421.50 at the time of publication.
News
Morgan Stanley’s Adam Jonas dubs Tesla FSD a “game changer” after marathon drive
Jonas reported that FSD handled more than 99% of the miles.

Morgan Stanley’s analyst Adam Jonas shared a notable endorsement of Tesla’s Full Self-Driving (FSD) software after completing a 1,400-mile round trip from New York to Michigan in his Model Y.
Jonas reported that FSD handled more than 99% of the miles, calling the system “a game changer” for long-distance driving.
Hands-free experience
Jonas drove his 2021 Tesla Model Y equipped with Hardware 3 and FSD Supervised v12.6.4, and he used the system nearly the entire trip. “Having your hands off the wheel and feet off the pedals for nearly 12 hours of driving is a real game changer that is hard to appreciate without experiencing it for yourself,” he noted.
He explained that outside of two heavy downpours, one on the Pennsylvania Turnpike and another in suburban Detroit, plus some light maneuvering in fast food parking lots, FSD handled the drive without any human intervention. “FSD made no mistakes or close calls that I recall. The system handles highways very safely and confidently. I cannot imagine buying another EV without FSD.”
Broader implications
Jonas added that he has used FSD consistently over the past 18 months, and the $8,000 he paid for the feature feels like a bargain considering the value. He also praised Tesla’s Supercharging network, which supported his trip without issue.
Jonas has been one of Wall Street’s most closely followed voices on Tesla, and his comments add weight to the ongoing debate about the role of autonomy in the company’s future. His current price target for Tesla stock stands at $410. During Morgan Stanley’s 13th Annual Laguna Conference, he echoed similar experiences with Tesla’s software, emphasizing that FSD “probably drove well over 99% of the miles” on his recent trips.
Elon Musk
Elon Musk just bought $1 billion in Tesla stock, his biggest purchase ever
Prior to this latest move, Musk’s most recent purchase was for about 200,000 shares worth $10 million in 2020.

Tesla (NASDAQ:TSLA) shares rose on Monday after CEO Elon Musk disclosed a rare insider purchase of company stock worth about $1 billion.
A filing with the U.S. Securities and Exchange Commission (SEC) revealed that Musk acquired 2.57 million shares last Friday at various prices. The move represents Musk’s largest TSLA purchase ever by value, as per Verity data.
Elon Musk’s TSLA purchase
The disclosure sent Tesla shares up more than 8% in premarket trading Monday, as investors read the purchase as a notable vote of confidence, as stated in a CNBC report. Tesla stock had closed slightly lower Friday but remains more than 25% higher over the past three months. It should be noted that prior to this latest move, Musk’s most recent purchase was for about 200,000 shares worth $10 million in 2020.
Market watchers say the purchase could help shore up investor sentiment amid a volatile year for TSLA stock. Shares have faced pressure from a variety of factors, from year-over-year sales challenges due to the new Model Y changeover, political controversies tied to Musk, and reduced U.S. incentives for EVs under the Trump administration. Nevertheless, analysts such as Wedbush’s Dan Ives stated that Musk’s purchase was a “huge sign of confidence for Tesla bulls and shows Musk is doubling down on his Tesla A.I. bet.”
Tesla and Elon Musk
Musk already owns about 13% of Tesla, and his latest purchase comes as the company prepares for a key shareholder vote in November. Investors will decide whether to approve a compensation package for Musk that could ultimately be worth as much as $975 billion if ambitious market value milestones are achieved. The package has a long-term target of pushing Tesla’s market capitalization to $8.5 trillion, compared with about $1.3 trillion at Friday’s close.
Wall Street’s current consensus price target still implies a roughly 20% decline from current levels, though some Tesla bulls remain optimistic that the company could shift its focus toward autonomy, AI, and robotics. Musk has also asked shareholders to approve an investment into his latest venture, xAI.
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