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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
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“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 will resolve its massive recall of nearly three million vehicles in China with stickers and a software update.
On Friday, Chinese regulators filed recall plans against Tesla, Xiaomi, Leapmotor, Xpeng, Chery, Geely, Dongfeng, Arcfox, and FAW to resolve what is essentially a carbon-copy issue throughout each of the companies’ vehicle models: emergency door release latches are simply not visible enough.
Tesla door handle saga gets its latest chapter and a big change is coming
The companies will be required to add things that will make these latches, which will open the door in the event of an emergency, more visible. Of the 7 million vehicles impacted, Tesla accounts for 2,975,910 units. More than 1.9 million of those are Model Y vehicles, with the rest, just over 970,000, being Model 3s.
To resolve the issue, Tesla is going to add warning labels to the emergency latches free of charge, and then utilize an Over-the-Air update to add a post-crash window-lowering strategy, according to CNEVpost.
This massive effort to fix the all-electric Model Y and Model 3’s emergency latch system comes just months after several probes across various markets identified the trouble some had identifying this latch. Those who had gotten involved in car accidents that stripped the vehicle of its power were not aware that every Tesla has emergency door latches.
China’s State Administration for Market Regulation (SAMR) said that severe crashes that disable a vehicle’s low-voltage system could not only hinder occupants from getting out, but also make it more difficult for emergency response workers to gain entry.
SAMR is starting to tighten the regulations it has on door handles on vehicles. A new mandatory national standard will take effect for all models starting January 1, 2027, and will require all doors to be equipped with mechanical release mechanisms. This will effectively end purely electronic door handles. Models already on sale with type approval have been granted a two-year transition period, which will enable things to change until January 2029.
Tesla has officially confirmed plans to bring its all-electric Semi truck to Europe, with full specifications and market-launch details set for unveiling at the IAA Transportation trade fair in Hannover, Germany.
The event runs September 15–20, with a possible press preview on September 14. The announcement, shared via Tesla’s Semi account, marks a significant expansion beyond North America nearly nine years after the truck’s original 2017 reveal.
🚨 Tesla Semi is coming to Europe!
Sustainable logistics is a huge market internationally, and now Tesla is involved in it outside of the U.S. market! https://t.co/q3hjX6ybMv pic.twitter.com/mxTaVY3UsE
— TESLARATI (@Teslarati) August 20, 2026
In the United States, the Semi’s path has been gradual. Limited pilot production and customer deliveries began in late 2022, primarily to fleets such as PepsiCo. After years of refinement, high-volume manufacturing started on April 29, 2026, at a dedicated facility adjacent to Gigafactory Nevada.
The plant targets an annual capacity of 50,000 units, though the ramp is expected to be gradual, with “many thousands” of trucks projected by the end of 2026.
Demand is building, with recent orders including 500 units for Einride (deliveries starting September 2026, serving Amazon and others) and hundreds more from operators such as WattEV. Pricing stands at approximately $260,000 for the Standard Range and $290,000 for the Long Range before incentives.
Tesla Semi pricing revealed after company uncovers trim levels
Earlier in 2026, Tesla finalized production specifications that incorporated substantial updates. In February, the company detailed two variants designed for a full 82,000-pound gross combination weight.
The Standard Range offers about 325 miles of range with a 548 kWh battery and curb weight under 20,000 pounds. The Long Range delivers roughly 500 miles with an 822 kWh pack and a 23,000-pound curb weight. Both use three independent rear-axle motors producing up to 800 kW (about 1,073 horsepower), achieve energy consumption of around 1.7 kWh per mile, and support megawatt-class charging at up to 1.2 MW—recovering about 60 percent of range in 30 minutes through the MCS standard.
Additional refinements include a roughly 1,000-pound weight reduction versus earlier prototypes, improved aerodynamics, a 48-volt electrical architecture, electric power take-off up to 25 kW for refrigerated trailers, and fleet management software with over-the-air updates.
These advances position the Semi as a competitive option against diesel trucks on operating costs and performance. For Europe, adaptations such as lighting, cab configurations (including potential sleeper options), and regulatory compliance are anticipated.
With series production underway in Nevada and major fleet commitments secured, the upcoming IAA reveal will clarify timelines, European-specific specs, and pricing, potentially accelerating electrification of heavy-duty freight on both continents.
Investor's Corner
Tesla Robotaxi gets a massive upgrade in Nevada
Nevada regulators just approved a massive expansion of Tesla’s robotaxi fleet across the entire county.
Tesla’s robotaxi footprint in Nevada just grew by roughly 500 times in a single regulatory vote.
The Nevada Transportation Authority approved Tesla’s full Autonomous Vehicle Network Company permit on Thursday, clearing the way for the company to deploy up to 5,000 driverless vehicles across Clark County over the next 12 months. The decision came during a four hour general session meeting that Tesla investor Sawyer Merritt watched live and reported on X, noting the vote replaces the interim order that had limited Tesla to just 10 robotaxis on a narrow stretch of the Las Vegas Strip.
EXCLUSIVE: Tesla has just officially received approval for its full Autonomous Vehicle Network Company permit in Nevada, clearing the way for Tesla to launch a paid public Robotaxi service in Las Vegas.
This officially allows @Tesla to deploy up to 5,000 robotaxis over the next… pic.twitter.com/DPs5UtUlrE
— Sawyer Merritt (@SawyerMerritt) August 20, 2026
That earlier cap, covered here after it surfaced on August 13, came with restrictions that looked stricter than what Tesla runs in Austin: a 45 mph speed ceiling, no airport pickups, and a geofence confined to the Strip corridor. The new approval extends Tesla’s operating authority to all of Clark County, with room to request an even wider geofence across the state.
Tesla representatives at the meeting said they have no intention of putting 5,000 cars on the road right away. Commercial rides are expected to start within 30 days, pending vehicle inspections, insurance filings, and fare approval, the standard steps every robotaxi operator in Nevada has had to clear.
Tesla’s own Robotaxi account replied to the news with a short line, The golden future is upon us.
The timing lines up with Tesla’s broader robotaxi push this month. The company is preparing to open Cybercab rides to the public in Austin as soon as this month, and it opened a sweepstakes for riders to win a seat at the launch event. Tesla filed its original application for a 5,000 vehicle Nevada fleet back in June, a request regulators trimmed to 10 vehicles when they issued the interim order in July. Thursday’s vote effectively grants the number Tesla asked for from the start.
Zoox, the Amazon owned robotaxi operator, has run in Nevada since 2025 and was capped at 100 vehicles before Thursday’s decision. Tesla’s new ceiling puts it well ahead of that comparison on paper, though the company has said its actual fleet size will depend on how quickly FSD v15 rolls out, the software update executives have called the gateway to scaling unsupervised robotaxi operations nationwide.
Tesla will resolve massive China recall with stickers and a software update
Tesla Semi is officially headed to Europe
