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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 just tipped its hand on a major Cybercab feature as production hits Plaid Mode
Tesla has delivered a clear signal that its Robotaxi ambitions are shifting into high gear. On April 17, longtime factory observer and drone pilot Joe Tegtmeyer captured drone footage and still images showing approximately 14 freshly built Cybercabs parked in the outbound lot—each one conspicuously lacking a steering wheel.
Tesla just tipped its hand on a major Cybercab feature as it is putting production into Plaid Mode, but a clear indication of what the company plans to do with the vehicle is now apparent.
Tesla has delivered a clear signal that its Robotaxi ambitions are shifting into high gear, and it’s doing it with full autonomy in mind.
On April 17, longtime factory observer and drone pilot Joe Tegtmeyer captured drone footage and still images showing approximately 14 newly built Cybercabs parked in the outbound lot, each conspicuously lacking a steering wheel, and potentially pedals.
Tegtmeyer’s post highlighted the significance of this development: The images and video reveal sleek, two-seat Cybercabs in their final production form: no driver controls, no side mirrors, and the minimalist interior first unveiled at Tesla’s “We Robot” event in October 2024.
Something big has changed at Giga Texas with Cybercab production … ~ 14 in the outbound lot WITHOUT STEERING WHEELS!
Earlier this week, the production line has begun what we are all waiting for and I would expect to see many more starting on Monday, 4/20 🤠
A big step… pic.twitter.com/K17ZzBlQ8k
— Joe Tegtmeyer 🚀 🤠🛸😎 (@JoeTegtmeyer) April 17, 2026
These units contrast with earlier test vehicles spotted at the factory’s crash-test area, which carried temporary steering wheels and pedals to meet current federal regulations during data-collection phases.
The outbound-lot vehicles appear complete, with production wheels, tire stickers, and the signature Cybercab styling ready for deployment.
This sighting represents a pivotal transition. Tesla designed the Cybercab from the ground up as a purpose-built robotaxi, engineered for unsupervised Full Self-Driving (FSD) operation. Removing manual controls eliminates cost, complexity, and weight while maximizing interior space and range.
The move also signals that Tesla has cleared initial validation hurdles and is now building vehicles to the exact specification intended for commercial robotaxi service.
Industry watchers note the timing aligns with Tesla’s broader rollout plans. Production of early Cybercabs began in late 2025 and early 2026, primarily for internal testing and regulatory compliance.
Federal Motor Vehicle Safety Standards currently limit vehicles without steering wheels to 2,500 units per year without exemption, a cap that Tesla is navigating through ongoing filings.
Tesla Cybercab spotted next to Model Y shows size comparison
The appearance of steering-wheel-free units in the outbound lot suggests the company is preparing a small initial fleet—likely for Austin pilot operations or further validation—while pushing for regulatory relief to scale output.
The development comes as Tesla ramps its dedicated Cybercab line at Gigafactory Texas. If the Monday surge materializes as predicted, observers expect dozens more units to accumulate rapidly.
With unsupervised FSD advancing and regulatory conversations ongoing, these wheel-less Cybercabs parked under the Texas sun represent more than hardware—they embody Tesla’s bet that autonomous mobility is no longer a prototype dream but an imminent reality.
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Tesla preps new Model Y trim for India, a once-elusive market
Tesla’s journey into India began with significant hurdles. For years, the electric vehicle giant faced steep import tariffs ranging from 70 percent to 110 percent on fully built vehicles, which dramatically inflated prices and stalled entry plans.
Tesla is preparing to bring its newest Model Y trim to India, a once-elusive market that was hesitant to allow any vehicles built outside the market into its automotive sector.
Now, it is preparing to allow China-built Model Y vehicles to come into the country, in an effort to expand sales and offer what is a widely-requested variant to Indian customers.
Tesla’s journey into India began with significant hurdles. For years, the electric vehicle giant faced steep import tariffs ranging from 70 percent to 110 percent on fully built vehicles, which dramatically inflated prices and stalled entry plans.
Elon Musk repeatedly criticized these duties as among the world’s highest, making premium EVs like the Model Y prohibitively expensive for most buyers in the price-sensitive market.
After prolonged negotiations and multiple delays, Tesla finally debuted in July 2025 with a quiet rollout focused on luxury segments. It opened showrooms in Mumbai and New Delhi, importing standard Model Y SUVs from its Shanghai Gigafactory.
Tesla China posts strong February wholesale growth at Gigafactory Shanghai
Yet the launch proved challenging: vehicles carried sticker prices near $70,000, leading to tepid demand. Bloomberg reported only about 600 orders in the first two months, while official data showed just 227 registrations for all of 2025—far below internal targets. By early 2026, the company offered discounts of up to ₹200,000 ($2,200) to clear unsold inventory.
Now, less than a year later, Tesla is demonstrating resilience and adaptability. According to a Bloomberg report on April 17, the company is preparing to launch the Model Y L—a six-seat, long-wheelbase variant with three-row seating—as early as next week.
This marks Tesla’s first new product introduction in India since its initial entry. Notably, the newest Model Y configuration, which debuted in China in 2025 and features extended space tailored for families, will once again be exported directly from Tesla’s Shanghai Gigafactory.
The move highlights a shift from early struggles to a more targeted approach, leveraging an existing platform to better suit Indian preferences for multi-generational, spacious SUVs without committing to immediate local production.
Tesla launches in India with Model Y, showing pricing will be biggest challenge
The Model Y L’s arrival underscores Tesla’s incremental strategy amid global EV headwinds and India’s unique challenges, including limited charging infrastructure and competition from local manufacturers.
While tariffs continue to keep pricing in the premium segment, the six-seater variant aims to broaden appeal beyond early luxury adopters by addressing practical family needs.
This evolution, from battling high barriers and disappointing initial sales to exporting its latest derivative model, signals cautious optimism.
Success with the Model Y L could strengthen Tesla’s foothold in one of the world’s most populous markets and potentially pave the way for deeper investments, such as localized manufacturing, should tariff relief or policy shifts materialize.
For now, the China-to-India supply chain represents a pragmatic bridge over the very obstacles that once made entry so difficult.
Elon Musk
Tesla’s golden era is no longer a tagline
Tesla “golden era” teaser video highlights the future of transportation and why car ownership itself may be the next thing to change.
The golden age of autonomous ridesharing is arriving, and Tesla is making sure we can all picture a future that looks like the future. A recent teaser posted to X shows a Cybercab parked outside a home, and with a clear message that your everyday life may soon look like this when the driverless vehicles shows up at your door.
Tesla has begun the rollout of its Robotaxi service across US cities, and the production of its dedicated, fully-autonomous Cybercab vehicle. The first Cybercab rolled off the Giga Texas assembly line on February 17, 2026, with volume production now targeted for this month. Additionally, the Robotaxi service built around it is already running, without human drivers, in US cities.
Tesla Cybercab production ignites with 60 units spotted at Giga Texas
The Cybercab is built without a steering wheel, pedals, or side mirrors, designed from the ground up for unsupervised autonomous operation. Musk described the manufacturing approach as closer to consumer electronics than traditional car production, targeting a cycle time of one unit every ten seconds at full scale.
Drone footage from April 13, 2026 captured over 50 Cybercab units on the Giga Texas campus, with several clustered near the crash testing facility. Musk has noted that Tesla plans to sell the Cybercab to consumers for under $30,000, and owners will be able to add their vehicles to the Tesla robotaxi network when not in personal use, potentially generating income to offset the vehicle’s purchase cost. That model changes the math on vehicle ownership in a meaningful way, making a car something closer to a depreciating asset that can also earn by paying itself off and generate a profit.
During Tesla’s Q4 earnings call, the company confirmed plans to expand the Robotaxi program to seven new cities in the first half of 2026, including Dallas, Houston, Phoenix, Miami, Orlando, Tampa, and Las Vegas. The service already runs without safety drivers in Austin, and public road testing of the Cybercab has expanded to five states, including California, Texas, New York, Illinois, and Massachusetts.
Golden era pic.twitter.com/AS6pX2dK8N
— Tesla Robotaxi (@robotaxi) April 16, 2026
Tesla just tipped its hand on a major Cybercab feature as production hits Plaid Mode
Tesla preps new Model Y trim for India, a once-elusive market
