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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Tesla is looking to expand into a new Asian market, strengthening its presence in a region that has been bullish on electric vehicles as a whole.
Tesla officially filed to establish a subsidiary of its business in Vietnam, a report from Reuters suggests. Tesla named the entity “Tesla Motors Vietnam Limited Liability Company.”
The planned entrance into the Vietnamese market is a good sign and move for Tesla, as it has become one of the fastest-growing EV markets in Southeast Asia. It is already among the leaders in the region in both volume and electrification rate. In the first half of this year, Vietnam led Southeast Asia in battery-electric passenger car sales at about 116,000 units, up about 71 percent year over year.
Currently, Vietnamese EV drivers rely on VinFast’s V-Green network, which has about 150,000 ports, but these are primarily reserved for VinFast vehicles. Public third-party charging is fragmented and unreliable for those who do not own chargers that are dedicated to a certain manufacturer’s vehicles.
Tesla has had mixed results in Asia as a whole, and as China remains the core part of its story in Asia, the company is evidently working on expanding its footprint on the continent. Tesla’s domestic retail deliveries fell about 12 percent year over year through the first eight months of 2026.
Model Y remains a standout individual product, holding its position as one of, if not the, best-selling vehicles in the world. However, Model 3 has been weaker than it has been in past years.
Gigafactory Shanghai, the company’s Chinese production facility, still performs very well. Wholesale volumes in terms of exports have more than doubled and now exceed domestic retail sales; Giga Shanghai builds vehicles for Europe, South Korea, Japan, Australia, and other markets. South Korea has been an explicit bright spot, with registrations doubling year-to-date and Tesla frequently appearing as the top imported brand.
Tesla just did something in South Korea that no foreign carmaker has ever done
Tesla’s entrance into Vietnam signals a broader effort to take over the Asian market and grab more market share from rivals.
Elon Musk
Elon Musk’s companies made up with Apple but OpenAI still on the hook
Elon Musk’s X Corp and SpaceXAI dropped their Apple antitrust suit, leaving OpenAI as defendant.
X Corp and SpaceXAI, Elon Musk’s social platform and AI venture, have dropped Apple from the antitrust lawsuit that they filed against the iPhone maker and OpenAI last year. In a filing in the U.S. District Court for the Northern District of Texas, attorneys for X and SpaceXAI moved to dismiss the Apple portion of the case, first reported by Reuters. The filing does not explain why the companies are dropping Apple or say whether a settlement was reached.
X and SpaceXAI say they intend to keep pursuing the case against OpenAI, which remains a defendant. That resolves the dispute with one company while leaving the core allegation intact against the other, with no public accounting of what changed in between.
The lawsuit dates to August 2025, when xAI and X sued Apple and OpenAI, arguing that Apple’s decision to make ChatGPT the only generative AI chatbot built into iOS gave OpenAI an unfair structural advantage. The complaint claimed ChatGPT controlled roughly 80 percent of the chatbot market at the time, while Grok held only a few percent. It sought billions of dollars in damages and asked the court to unwind the arrangement.
Elon Musk’s xAI and X file antitrust suit against Apple and OpenAI over AI exclusivity
The filing followed weeks of Musk publicly complaining that Grok and X weren’t appearing in Apple’s “Must Have” App Store section, though Grok ranked second in the Productivity category and X ranked first in News at the time. He accused Apple of “playing politics” and warned of immediate legal action before following through days later.
Apple and OpenAI tried to get the case thrown out, but a federal judge denied both motions in November, ruling the dispute was better suited to summary judgment than an early dismissal. That decision sent the case into discovery, which is presumably what led to Monday’s filing.
Hey @Apple App Store, why do you refuse to put either 𝕏 or Grok in your “Must Have” section when 𝕏 is the #1 news app in the world and Grok is #5 among all apps?
Are you playing politics? What gives? Inquiring minds want to know. https://t.co/3wenLZGtwG
— Elon Musk (@elonmusk) August 11, 2025
The timing is notable given how Musk’s sentiment toward Apple has shifted, with Musk noting that he was open to letting Grok power a revamped Siri after a user suggested Apple replace its aging assistant with xAI’s model.
xAI, the AI venture Musk folded into X Corp last year, has since combined with SpaceX under the SpaceXAI brand. That structure now puts X, Grok and SpaceX’s rocket and satellite businesses under one roof as Musk pushes his AI ambitions beyond chatbots.
OpenAI remains the sole defendant going forward, and Musk’s companies have not said if there’s any changes to those original claims. Apple and OpenAI did not immediately respond to requests for comment on the filing.
News
Why SpaceX is finishing another space-internet system that isn’t Starlink
SpaceX launched three final O3b mPower satellites Sunday, finishing a lesser known SES satellite network.
SpaceX had an 87 minute window opening at 2:49 p.m. Eastern on Sunday to fly a Falcon 9 out of Cape Canaveral carrying the final three satellites for SES’s O3b mPower constellation, a project that has taken more than a decade to finish since Boeing and SES first signed SpaceX on for the work.
Unlike the thousands of Starlink satellites SpaceX has stacked into orbit over the years, O3b mPower flies in a different neighborhood entirely. The three new satellites, tagged F11, F12 and F13, are headed for medium Earth orbit at roughly 5,000 miles up, more than ten times higher than Starlink’s shell around 340 miles but still a small fraction of the 22,000 miles where old school geostationary satellites sit. That middle position is the whole point, because a satellite that far out needs far fewer siblings to blanket the globe than a low orbit constellation does. Essentially, SES only needed 13 satellites total to build a network offering quick, steady service that used to require thousands of spacecraft.
With most people having heard plenty about Starlink and almost nothing about O3b mPower, SES and SpaceX already blend the two networks for some customers. Both SpaceX and SES sell satellite broadband, but they’re aimed at different buyers. Starlink is built for volume, direct to consumers, RVs, homes, small businesses, plus a growing aviation and maritime business. O3b mPower skips consumers entirely and sells enterprise grade connectivity to airlines, cruise lines, offshore energy operators, telecoms needing backhaul, and governments, priced and provisioned more like a dedicated circuit.
A 2023 partnership lets cruise ships combine Starlink’s speed with O3b mPower’s steady capacity depending on what a ship needs at a given moment. Sunday’s completed 13 satellite constellation effectively finishes the medium orbit half of that pairing, years after.
Sunday’s mission was already a something on SpaceX’s manifest well before O3b mPower entered the picture. This flight marked its 29th trip to orbit, a history that includes two crewed Axiom missions, the European Space Agency’s Euclid telescope and 22 separate Starlink batches. SpaceX has landed boosters on the droneship A Shortfall of Gravitas so often that Sunday’s touchdown attempt, if it went as planned, was set to be the 661st successful Falcon booster landing to date.
For a company that pushed the Starlink constellation past 11,000 satellites back in August, almost entirely through bulk launches from California, Sunday’s flight was a reminder that SpaceX’s schedule still has room for someone else’s satellites too. SES gets a finished network built for a narrower set of customers, and Falcon 9 gets one more line on an already long resume.
Tesla looks to expand into new Asian market, strengthening presence
Elon Musk’s companies made up with Apple but OpenAI still on the hook
