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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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Tesla has made two big interior changes to several Model Y vehicles in its lineup, and the changes come just as the new model year begins production.
Last year, Tesla launched the Model Y Standard, which separated the previous models into the “Premium” category. The Standard vehicles lack several features, including more premium interior materials, acoustic-lined glass, and storage.
@teslarati There are some BIG differences between the Tesla Model Y Standard and Tesla Model Y Premium #tesla #teslamodely ♬ Sia – Xeptemper
The Model Y “Premium” trims are now getting several new upgrades, which come after the company launched a seven-seat configuration of the vehicle last night in the North American market for an upcharge of $2,500.
The new Model Y seven-seat configuration did not come with just an additional row of seating; it also came with a slew of other goodies that now come standard and were previously only available on the Model Y Performance, which was launched late last year.
All Black Headliner
The new Tesla Model Y Premium trims will now come standard with a black headliner, something that many owners have been requesting for some time.
The previous grey headliner and trim within the vehicle is now gone; it will be all black on all of the Premium trims from here on out, a welcome change:
Credit: Tesla
Larger and Higher Resolution Center Touchscreen
The center touchscreen in the new Model Y Premium configuration is now larger and has a higher resolution than the previous version.
In last year’s Model Y configurations (apart from the Performance), the center touchscreen was 15.4″. Now, Tesla has decided to go with the 16″ version across all Premium trims, which is a nice step up. It was nice to see this in the Performance, but it is really great to see Tesla include this in the Model Y’s more Premium trim levels.
Tesla Model Y Seven Seater
Tesla launched the latest iteration of the seven-seater for the Model Y on Monday night. Traditionally, the Model Y seats five passengers in total, but there were calls for a more spacious version several years ago.
Tesla released it, but it was extremely tight in the back, basically reserving those back seats for only small people or children.
Credit: Tesla
The new configuration looks to be slightly more spacious in the third row, but not as much space as most would require or want. Instead,
Elon Musk
Lufthansa Group to equip Starlink on its 850-aircraft fleet
Under the collaboration, Lufthansa Group will install Starlink technology on both its existing fleet and all newly delivered aircraft, as noted by the group in a press release.
Lufthansa Group has announced a partnership with Starlink that will bring high-speed internet connectivity to every aircraft across all its carriers.
This means that aircraft across the group’s brands, from Lufthansa, SWISS, and Austrian Airlines to Brussels Airlines, would be able to enjoy high-speed internet access using the industry-leading satellite internet solution.
Starlink in-flight internet
Under the collaboration, Lufthansa Group will install Starlink technology on both its existing fleet and all newly delivered aircraft, as noted by the group in a press release.
Starlink’s low-Earth orbit satellites are expected to provide significantly higher bandwidth and lower latency than traditional in-flight Wi-Fi, which should enable streaming, online work, and other data-intensive applications for passengers during flights.
Starlink-powered internet is expected to be available on the first commercial flights as early as the second half of 2026. The rollout will continue through the decade, with the entire Lufthansa Group fleet scheduled to be fully equipped with Starlink by 2029. Once complete, no other European airline group will operate more Starlink-connected aircraft.
Free high-speed access
As part of the initiative, Lufthansa Group will offer the new high-speed internet free of charge to all status customers and Travel ID users, regardless of cabin class. Chief Commercial Officer Dieter Vranckx shared his expectations for the program.
“In our anniversary year, in which we are celebrating Lufthansa’s 100th birthday, we have decided to introduce a new high-speed internet solution from Starlink for all our airlines. The Lufthansa Group is taking the next step and setting an essential milestone for the premium travel experience of our customers.
“Connectivity on board plays an important role today, and with Starlink, we are not only investing in the best product on the market, but also in the satisfaction of our passengers,” Vranckx said.
Elon Musk
Tesla locks in Elon Musk’s top problem solver as it enters its most ambitious era
The generous equity award was disclosed by the electric vehicle maker in a recent regulatory filing.
Tesla has granted Senior Vice President of Automotive Tom Zhu more than 520,000 stock options, tying a significant portion of his compensation to the company’s long-term performance.
The generous equity award was disclosed by the electric vehicle maker in a recent regulatory filing.
Tesla secures top talent
According to a Form 4 filing with the U.S. Securities and Exchange Commission, Tom Zhu received 520,021 stock options with an exercise price of $435.80 per share. Since the award will not fully vest until March 5, 2031, Zhu must remain at Tesla for more than five years to realize the award’s full benefit.
Considering that Tesla shares are currently trading at around the $445 to $450 per share level, Zhu will really only see gains in his equity award if Tesla’s stock price sees a notable rise over the years, as noted in a Sina Finance report.
Still, even at today’s prices, Zhu’s stock award is already worth over $230 million. If Tesla reaches the market cap targets set forth in Elon Musk’s 2025 CEO Performance Award, Zhu would become a billionaire from this equity award alone.
Tesla’s problem solver
Zhu joined Tesla in April 2014 and initially led the company’s Supercharger rollout in China. Later that year, he assumed the leadership of Tesla’s China business, where he played a central role in Tesla’s localization efforts, including expanding retail and service networks, and later, overseeing the development of Gigafactory Shanghai.
Zhu’s efforts helped transform China into one of Tesla’s most important markets and production hubs. In 2023, Tesla promoted Zhu to Senior Vice President of Automotive, placing him among the company’s core global executives and expanding his influence beyond China. He has since garnered a reputation as the company’s problem solver, being tapped by Elon Musk to help ramp Giga Texas’s vehicle production.
With this in mind, Tesla’s recent filing seems to suggest that the company is locking in its top talent as it enters its newest, most ambitious era to date. As could be seen in the targets of Elon Musk’s 2025 pay package, Tesla is now aiming to be the world’s largest company by market cap, and it is aiming to achieve production levels that are unheard of. Zhu’s talents would definitely be of use in this stage of the company’s growth.
Tesla makes two big interior changes to several Model Y vehicles
Lufthansa Group to equip Starlink on its 850-aircraft fleet
