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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Elon Musk
Starlink achieves major milestones in 2025 progress report
Starlink wrapped up 2025 with impressive growth, adding more than 4.6 million new active customers and expanding service to 35 additional countries, territories, and markets.
Starlink wrapped up 2025 with impressive growth, adding more than 4.6 million new active customers and expanding service to 35 additional countries, territories, and markets. The company also completed deployment of its first-generation Direct to Cell constellation, launching over 650 satellites in just 18 months to enable cellular connectivity.
SpaceX highlighted Starlink’s impressive 2025 progress in an extensive report.
Key achievements from Starlink’s 2025 Progress
Starlink connected over 4.6 million new customers with high-speed internet while bringing service to 35 more regions worldwide in 2025. Starlink is now connecting 9.2 million people worldwide. The service achieved this just weeks after hitting its 8 million customer milestone.
Starlink is now available in 155 markets, including areas that are unreachable by traditional ISPs. As per SpaceX, Starlink has also provided over 21 million airline passengers and 20 million cruise passengers with reliable high-speed internet connectivity during their travels.
Starlink Direct to Cell
Starlink’s Direct to Cell constellation, more than 650 satellites strong, has already connected over 12 million people at least once, marking a breakthrough in global mobile coverage.
Starlink Direct to Cell is currently rolled out to 22 countries and 6 continents, with over 6 million monthly customers. Starlink Direct to Cell also has 27 MNO partners to date.
“This year, SpaceX completed deployment of the first generation of the Starlink Direct to Cell constellation, with more than 650 satellites launched to low-Earth orbit in just 18 months. Starlink Direct to Cell has connected more than 12 million people, and counting, at least once, providing life-saving connectivity when people need it most,” SpaceX wrote.
News
Tesla Giga Nevada celebrates production of 6 millionth drive unit
To celebrate the milestone, the Giga Nevada team gathered for a celebratory group photo.
Tesla’s Giga Nevada has reached an impressive milestone, producing its 6 millionth drive unit as 2925 came to a close.
To celebrate the milestone, the Giga Nevada team gathered for a celebratory group photo.
6 million drive units
The achievement was shared by the official Tesla Manufacturing account on social media platform X. “Congratulations to the Giga Nevada team for producing their 6 millionth Drive Unit!” Tesla wrote.
The photo showed numerous factory workers assembled on the production floor, proudly holding golden balloons that spelled out “6000000″ in front of drive unit assembly stations. Elon Musk gave credit to the Giga Nevada team, writing, “Congrats on 6M drive units!” in a post on X.
Giga Nevada’s essential role
Giga Nevada produces drive units, battery packs, and energy products. The facility has been a cornerstone of Tesla’s scaling since opening, and it was the crucial facility that ultimately enabled Tesla to ramp the Model 3 and Model Y. Even today, it serves as Tesla’s core hub for battery and drivetrain components for vehicles that are produced in the United States.
Giga Nevada is expected to support Tesla’s ambitious 2026 targets, including the launch of vehicles like the Tesla Semi and the Cybercab. Tesla will have a very busy 2026, and based on Giga Nevada’s activities so far, it appears that the facility will be equally busy as well.
News
Tesla Supercharger network delivers record 6.7 TWh in 2025
The network now exceeds 75,000 stalls globally, and it supports even non-Tesla vehicles across several key markets.
Tesla’s Supercharger Network had its biggest year ever in 2025, delivering a record 6.7 TWh of electricity to vehicles worldwide.
To celebrate its busy year, the official @TeslaCharging account shared an infographic showing the Supercharger Network’s growth from near-zero in 2012 to this year’s impressive milestone.
Record 6.7 TWh delivered in 2025
The bar chart shows steady Supercharger energy delivery increases since 2012. Based on the graphic, the Supercharger Network started small in the mid-2010s and accelerated sharply after 2019, when the Model 3 was going mainstream.
Each year from 2020 onward showed significantly more energy delivery, with 2025’s four quarters combining for the highest total yet at 6.7 TWh.
This energy powered millions of charging sessions across Tesla’s growing fleet of vehicles worldwide. The network now exceeds 75,000 stalls globally, and it supports even non-Tesla vehicles across several key markets. This makes the Supercharger Network loved not just by Tesla owners but EV drivers as a whole.
Resilience after Supercharger team changes
2025’s record energy delivery comes despite earlier 2024 layoffs on the Supercharger team, which sparked concerns about the system’s expansion pace. Max de Zegher, Tesla Director of Charging North America, also highlighted that “Outside China, Superchargers delivered more energy than all other fast chargers combined.”
Longtime Tesla owner and FSD tester Whole Mars Catalog noted the achievement as proof of continued momentum post-layoffs. At the time of the Supercharger team’s layoffs in 2024, numerous critics were claiming that Elon Musk was halting the network’s expansion altogether, and that the team only remained because the adults in the room convinced the juvenile CEO to relent.
Such a scenario, at least based on the graphic posted by the Tesla Charging team on X, seems highly implausible.
Starlink achieves major milestones in 2025 progress report
Tesla Giga Nevada celebrates production of 6 millionth drive unit
