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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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News
Tesla VP explains latest updates in trade secret theft case
Tesla reportedly caught Matthews copying the tech into machines that were sold to competitors, claiming they lied about doing so for three years, and continued to ship it. That is when Tesla chose to sue Matthews in July 2024 in Federal court, demanding over $1 billion in damages due to trade secret theft.
Tesla Vice President Bonne Eggleston explained the latest updates in a trade secret theft case the company has against a former manufacturing equipment supplier, Matthews International.
Back in 2024, Tesla had filed a lawsuit against Matthews International, alleging that the firm stole trade secrets about battery manufacturing and shared those details with some of Tesla’s competitors.
Early last year, a U.S. District Court Judge denied Tesla’s request to block Matthews International from selling its dry battery electrode (DBE) technology across the world. The judge, Edward Davila, said that the patent for the tech was due to Matthews’ “extensive research and development.”
The two companies’ relationship began back in 2019, as Tesla hired Matthews to help build the equipment for its 4680 battery cell. Tesla shared confidential software, designs, and know-how under strict secrecy rules.
Fast forward a few years, and Tesla reportedly caught Matthews copying the tech into machines that were sold to competitors, claiming they lied about doing so for three years, and continued to ship it. That is when Tesla chose to sue Matthews in July 2024 in Federal court, demanding over $1 billion in damages due to trade secret theft.
Now, the latest twist, as this month, a Judge issued a permanent injunction—a court order banning Matthews from using certain stolen Tesla parts or designs in their machines. Matthews is also officially “liable” for damages. The exact amount would still to be calculated later.
Bonne Eggleston, a VP for Tesla, said on X today that Matthews is a supplier who “exploited customer IP through theft or deception,” and has no place in Tesla’s ecosystem:
Buyer beware: Matthews International stole Tesla’s DBE technology and is now subject to an injunction and liable for damages.
During our work with Matthews, we caught them red-handed copying our technology—including proprietary software and sensitive mechanical designs—into… https://t.co/Toc8ilakeM
— Bonne Eggleston (@BonneEggleston) March 10, 2026
Tesla calls this a big win and warns other companies: “Buyer beware—don’t buy from thieves.”
Matthews hit back with a press release claiming victory. They say an arbitrator ruled they can keep selling their own DBE equipment to anyone and rejected Tesla’s request for a total sales ban. They call Tesla’s claims “nonsense” and insist their 20-year-old tech is independent. Both sides are spinning the same narrow ruling: Matthews can sell their version, but they’re blocked from using Tesla’s specific secrets.
What are Tesla’s Current Legal Options
The case isn’t over—it’s moving to the damages phase. Tesla can:
- Push forward in court or arbitration to calculate and collect huge financial penalties (potentially $1 billion+ if willful theft is proven).
- Enforce the permanent injunction with contempt charges, fines, or even jail time if Matthews violates it.
- Challenge Matthews’ new patents that allegedly copy Tesla’s work, asking courts to invalidate them or add Tesla as co-inventor.
- Seek extra damages, lawyer fees, and possibly punitive awards under the federal Defend Trade Secrets Act and California law.
Tesla could also refer evidence to federal prosecutors for possible criminal trade-secret charges (rare but serious). Settlement is always possible, but Tesla’s fiery public response suggests they want full accountability.
This isn’t just corporate drama. It shows why trade secrets matter even when Tesla open-sources some patents, confidential know-how shared in trust must stay protected. For the EV industry, it’s a reminder: steal from your biggest customer, and you risk losing everything.
News
Tesla Cybercab includes this small but significant feature
The Cybercab is Tesla’s big plan to introduce fully autonomous ride-sharing in a seamless fashion. In fact, the Full Self-Driving suite was geared toward alleviating the need to manually drive vehicles.
Tesla Cybercab manufacturing is strikingly close, as the company is still aiming for an April start date. But small and significant features are still being identified for the first time as production units appear all over the country for testing and for regulatory events, like one yesterday in Washington, D.C.
The Cybercab is Tesla’s big plan to introduce fully autonomous ride-sharing in a seamless fashion. In fact, the Full Self-Driving suite was geared toward alleviating the need to manually drive vehicles.
This was for everyone, including the disabled, who are widely reliant on ride-sharing platforms, family members, and medical shuttles for transportation of any kind. Cybercab aims to change that, and Tesla evidently put a focus on those riders while developing the vehicle, evident in a small but significant feature revealed during its appearance in the Nation’s Capital.
Tesla Cybercab display highlights interior wizardry in the small two-seater
Tesla has implemented Braille within the Cybercab to make it easier for blind passengers to utilize the vehicle. On both the ‘Stop/Hazard Lights’ button and the Door Releases, Tesla has placed Braille so that blind passengers can navigate their way through the vehicle:
The hazard lights button will be used as an emergency stop. Smart pic.twitter.com/vkYBioqmKm
— Whole Mars Catalog (@wholemars) March 10, 2026
We have braille on the interior door releases as well
— Eric (@EricETesla) March 11, 2026
This is a great addition to the Cybercab, especially as Full Self-Driving has been partially pointed at as a solution for those with disabilities that would keep them from driving themselves from place to place.
It truly is a great addition and just another way that Tesla is showing they are making this massive product inclusive for everyone out there, including those who have not been able to drive due to not having vision.
The Cybercab is set to enter mass production sometime in April, and it will be responsible for launching Tesla’s massive plans for an autonomous ride-sharing program.
Elon Musk
Tesla and xAI team up on massive new project
It is the latest move by a Musk company to automate, streamline, and reduce the manual, monotonous, and tedious work currently performed by humans through AI and robotics development. Digital Optimus will be capable of processing and actioning the past five seconds of a real-time computer screen video and keyboard and mouse actions.
Elon Musk teased a massive new project, to be developed jointly by Tesla and xAI, called “Digital Optimus” or “Macrohard,” the first development under Tesla’s investment agreement with xAI.
Musk announced on X that Digital Optimus will “be capable of emulating the function of entire companies.”
Macrohard or Digital Optimus is a joint xAI-Tesla project, coming as part of Tesla’s investment agreement with xAI.
Grok is the master conductor/navigator with deep understanding of the world to direct digital Optimus, which is processing and actioning the past 5 secs of…
— Elon Musk (@elonmusk) March 11, 2026
It is the latest move by a Musk company to automate, streamline, and reduce the manual, monotonous, and tedious work currently performed by humans through AI and robotics development. Digital Optimus will be capable of processing and actioning the past five seconds of a real-time computer screen video and keyboard and mouse actions.
Essentially, it will be an AI version of a desk worker in many capacities, including accounting, HR tasks, and others.
Musk said:
“Grok is the master conductor/navigator with deep understanding of the world to direct digital Optimus, which is processing and actioning the past 5 secs of real-time computer screen video and keyboard/mouse actions. Grok is like a much more advanced and sophisticated version of turn-by-turn navigation software. You can think of it as Digital Optimus AI being System 1 (instinctive part of the mind) and Grok being System 2. (thinking part of the mind).”
Its key applications would be used for enterprise automation, simulating entire companies, high-volume repetitive tasks, and potentially, future hybrid use with the Optimus robot, which would handle physical tasks, while Digital Optimus would handle the clerical work.
The creation of a digital AI suite like Digital Optimus would help companies save time and money, as well as become more efficient in their operations through massive scalability. However, there will undoubtedly be concerns from people who are skeptical of a fully-integrated AI workhorse like this one.
From an energy consumption perspective and just a general concern for the human workforce, these types of AI projects are polarizing in nature.
However, Digital Optimus would be a great digital counterpart to Tesla’s physical Optimus robot, as it would be a hyper-efficient addition to any company that is looking for more production for less cost.
Musk maintains that there is no other company on Earth that will be able to do this.
Tesla VP explains latest updates in trade secret theft case
Tesla Cybercab includes this small but significant feature
