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
SpaceX Board has set a Mars bonus for Elon Musk
SpaceX has given Elon Musk the goal to put one million people on Mars.
SpaceX’s board approved a compensation plan for Elon Musk that ties his pay directly to colonizing Mars and building data centers in outer space. The details surfaced this week after Reuters reviewed SpaceX’s confidential registration statement filed with the Securities and Exchange Commission, making it one of the first concrete looks inside the company’s financials ahead of a public offering.
The pay package will reportedly award Musk 200 million super-voting restricted shares if the company hits a market valuation milestone, with the most ambitious targets going further. To unlock the full award, SpaceX would need to reach a $7.5 trillion valuation and help establish a permanent human settlement on Mars with at least one million residents. Additional incentives are tied to developing space-based computing infrastructure capable of delivering at least 100 terawatts of processing power.
SpaceX wins its first MARS contract but it comes with a catch
Long before SpaceX filed anything with the SEC, Elon Musk had already spent years framing Mars colonization as an insurance policy against human extinction. The philosophy traces back to at least 2001, when Musk first began researching Mars missions independently, before SpaceX even existed. By 2002 he had founded the company with Mars as the stated long-term goal.
In a 2017 presentation at the International Astronautical Congress, Musk outlined the specific vision that still underpins SpaceX’s architecture today. He described a self-sustaining city on Mars requiring roughly one million people to become viable, the same number now written into his compensation package.
SpaceX’s Starship, still in active development, was designed from the ground up to support the eventual colonization of Mars. Musk has stated publicly that getting the cost per ton to Mars below $100,000 is necessary to make mass migration economically feasible. Everything from Starship’s payload capacity to its full reusability targets flows from that single constraint. One can say that Musk’s latest compensation package has put a formal valuation on Mars for the first time.
SpaceX is targeting an IPO around June 28, Musk’s birthday, at a valuation of approximately $1.75 trillion. Between the Mars rover contract, the Golden Dome software group, Space Force satellite launches, and now a pay structure built around interplanetary colonization, SpaceX has become the single most consequential contractor in American space and defense. The IPO will put a public price tag on all of it for the first time.
Earlier this week, we wrote a story on how Tesla is launching a new Supercharging Queue system to mitigate problems between drivers when there is a wait to charge.
Rather than potentially having people end up in a physical conflict, Tesla’s approach is to determine who is next to charge based on geographic data.
Tesla launches solution to end Supercharger fights once and for all
But some companies, notably Tesla’s biggest rival in China, BYD, are taking a different approach, focusing on charging speeds rather than how they will manage delays.
BYD’s approach, especially with its tests of ultra-fast “Flash Charging” technology, is to eliminate the length of a charging session. At the heart of this strategy is BYD’s second-generation Blade Battery paired with 1,500-kW Flash Chargers.
Real-world FLASH Charging in action.
⚡ 10% → 70% in 5 minutes
⚡ 10% → 97% in 9 minutesIntroducing BYD’s 2nd Generation Blade Battery + FLASH Charging Technology.
20,000 stations will bring faster, safer, and smarter EV charging across China by the end of 2026. pic.twitter.com/uzQC8q1xGf
— BYD (@BYDCompany) March 9, 2026
Unveiled earlier this year, the system charges compatible vehicles from 10 percent to 70 percent state of charge in just five minutes and from 10 percent to 97 percent in nine minutes.
Real-world demonstrations on models like the Yangwang U7 and Denza Z9 GT have shown the tech delivering roughly 250 miles (400 kilometers) of range in just five minutes. This would essentially match or beat the time it takes to fill a gas tank.
Sometimes, gas pumps get congested, and there are lines. You rarely see conflicts at pumps because filling up a tank rarely takes more than five minutes.
Tesla’s fastest Supercharger build currently is the v4, which can deliver up to 325 kW for Cybertruck and 250 kW for other models, but there are “true” sites that are capable of up to 500 kW. This enables speeds of up to 1,000 miles per hour, or 1,400 miles for 350 kW-capable vehicles.
The breakthrough stems from BYD’s vertically integrated ecosystem: a new 1,000-volt architecture, 10C charging rates, and proprietary silicon-carbide chips that minimize internal resistance while protecting battery health.
The company plans to install 20,000 Flash Charging stations across China by the end of 2026, with thousands already operational and global expansion eyed for Europe and beyond later this year.
Early rollout targets popular models, including upgrades to high-volume sellers like the Seal and Sealion series, bringing five-minute charging to mainstream prices around 100,000 yuan (about $14,000).
This approach contrasts sharply with Tesla’s software solution. Tesla’s Virtual Queue uses geofencing and the app to assign turns at crowded sites, addressing driver disputes and idle time. It’s a clever fix for today’s network realities.
Yet, BYD’s philosophy is simpler: make charging so fast that waits barely exist. A five-minute stop becomes as convenient as a gas-station visit, reducing station dwell time, easing grid strain, and lowering range anxiety for long trips.
For consumers, the difference is potentially tangible. They’ll spend more time driving and less time parked. It is just another way Tesla and BYD are pushing one another to improve the overall experience of EV ownership.
News
Tesla wins big as NHTSA drops three-year, 120k unit probe against Model Y
In all, 120,089 Model Ys were impacted, but in two cases, drivers reported the complete detachment of the steering wheel from the steering column while the vehicle was in motion. NHTSA’s initial review revealed that the vehicles had been delivered without the critical retaining bolt that secures the steering wheel to the splined steering column.
A probe into over 120,000 2023 Tesla Model Y units has been closed by the National Highway Traffic Safety Administration (NHTSA). The probe ends without the agency requiring any action from Tesla.
The probe, designated PE23-003, opened in March 2023 and stemmed from just two consumer complaints involving low-mileage Model Y SUVs.
In all, 120,089 Model Ys were impacted, but in two cases, drivers reported the complete detachment of the steering wheel from the steering column while the vehicle was in motion. NHTSA’s initial review revealed that the vehicles had been delivered without the critical retaining bolt that secures the steering wheel to the splined steering column.
NHTSA has ended a probe into over 120,000 Tesla Model Y vehicles after claims that the steering wheel could detach from the steering column due to a missing retaining bolt
There is no action needed by Tesla pic.twitter.com/YpAO3bKugA
— TESLARATI (@Teslarati) April 28, 2026
Factory records showed each car had undergone an “end-of-line” repair at Tesla’s facility, during which the steering wheel was removed and reinstalled. The bolt was apparently omitted after the repair, leaving only a friction fit between the wheel and column to hold it in place temporarily.
According to NHTSA documents, this friction fit maintained the connection during initial low-mileage driving until forces during normal operation caused the wheel to detach. Both vehicles that were impacted were repaired under warranty with no injuries reported, and no additional incidents surfaced during the agency’s three-year review.
After analyzing manufacturing processes, complaint data, and field reports, NHTSA concluded the issue was isolated to those two post-repair vehicles rather than indicative of a systemic defect in Tesla’s production or quality control.
The closure means the agency has determined no recall or further enforcement is warranted for this specific missing-bolt condition.
This outcome marks the second NHTSA investigation into Tesla closed without action this month, as a recent probe into the company’s “Actually Smart Summon” feature was also resolved in April.
The two resolutions provide some relief for Tesla amid the continuous and somewhat unfair regulatory scrutiny of its vehicles, including open inquiries into driver assistance systems.
Importantly, the closed probe does not involve or affect Tesla’s separate May 2023 voluntary recall of certain 2022-2023 Model Y vehicles. That recall addressed a different issue—steering-wheel fasteners that were installed but not torqued to specification—prompted by a service technician’s observation of a loose wheel during unrelated repairs.
Tesla identified a small number of related warranty claims and proactively addressed the matter without NHTSA mandate.
The Model Y remains one of the world’s best-selling vehicles, and Tesla continues to refine its lineup, including the recent “Juniper” refresh. While federal oversight of the electric vehicle pioneer remains intense, this decision underscores that isolated manufacturing anomalies do not always translate into broader safety defects requiring recalls.
SpaceX Board has set a Mars bonus for Elon Musk
Tesla’s biggest rivals fights charging wait times with a modern approach
