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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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NASA has filed a procurement notice announcing its intent to add six post-certification missions to SpaceX’s existing Commercial Crew Transportation Capability contract. The agency said it would order up to three of those missions immediately upon adding them to the contract, with the remaining three available as needed through the end of the International Space Station’s planned operations in 2030.
The reason for the expansion is straightforward. NASA cited recently shortened ISS mission durations, technical issues and schedule delays encountered by Boeing, the allocation of missions between Boeing and SpaceX, and the ongoing technical challenges of maintaining a reliable crew transportation capability as the driving factors behind the decision. Boeing’s CST-100 Starliner has still not been certified for crewed flights, and a cargo-only Starliner mission was not included on NASA’s most recent mission manifest. With Boeing effectively sidelined for the foreseeable future, SpaceX is the only American company capable of rotating crews to the station.
The history behind this contract tells the fuller story of how SpaceX got here. NASA originally awarded SpaceX its Commercial Crew contract in 2014 for $2.6 billion. In 2022 NASA modified the contract to add five missions covering Crew-10 through Crew-14, worth $1.436 billion, bringing the total contract value at that point to $4.9 billion. The recent May 18 filing by NASA extends that runway further, with Crew-12 currently docked at the station and Crew-13 assigned and targeting a mid-September 2026 launch.
According to a report by SpaceNews, NASA stated in its filing: “It is necessary to award additional PCMs to SpaceX given the recently shortened ISS mission durations, technical issues and schedule delays encountered by Boeing, the allocation of missions between Boeing and SpaceX, NASA’s projections for when an alternative crew transportation system may become available, and the ongoing technical challenges of maintaining a reliable capability for crewed flights to ISS.”
No dollar value for the new six missions has been publicly confirmed yet, but based on the 2022 precedent of roughly $287 million per mission, the new block could represent close to $1.7 billion in additional contract value. With SpaceX simultaneously preparing Starship as NASA’s Artemis lunar lander, filing its S-1 for a June IPO, and now absorbing more ISS crew rotation work, the company’s role as the primary contractor for American human spaceflight is no longer a matter of circumstance. It is NASA policy.
In a notable intersection of Big Tech powerhouses, Meta, led by Mark Zuckerberg, has partnered with Canadian energy infrastructure giant Enbridge on a significant renewable energy initiative that will rely on battery technology from Elon Musk’s Tesla.
The project, which was announced this week, marks another step in Meta’s aggressive push to power its expanding data center operations with clean energy, dispelling many of the complaints people have about them.
This new development is located near Cheyenne, Wyoming, and will feature a 365-megawatt (MW) solar farm paired with a 200 MW/1,600 megawatt-hour (MWh) battery energy storage system, also known as BESS. Tesla is providing the batteries for the project, valued at roughly $200 million.
The story was originally reported by Utility Dive.
This Wyoming project represents the first phase of Enbridge and Meta’s joint “Cowboy Project.” Once operational, it will deliver power to Meta’s regional data centers through Cheyenne Light, Fuel, and Power under Wyoming’s Large Power Contract Service tariff.
This tariff, originally developed in collaboration with Microsoft and Black Hills Energy, is designed specifically for large loads like data centers. It ensures that the renewable supply serves hyperscale customers without impacting retail electricity rates for other users.
The battery system will operate under a long-term tolling agreement, providing dispatchable capacity that enhances grid reliability. During periods of high demand, the utility can access the backup generation, addressing one of the key challenges of integrating large-scale renewables with the explosive growth of data center electricity demand driven by artificial intelligence.
This latest collaboration builds on prior joint efforts between Enbridge and Meta in Texas, including the 600 MW Clear Fork Solar, 152 MW Easter Wind, and 300 MW Cone Wind projects. Together with the Wyoming initiative, the companies have now partnered on roughly 1.6 gigawatts (GW) of combined solar, wind, and storage capacity.
The deal highlights the intensifying demand for reliable, low-carbon power from technology giants. Meta has committed to supporting its data center growth with renewable energy, joining peers like Microsoft and Google in seeking large-scale solutions. Enbridge’s Allen Capps described the project as “one of the larger utility-scale battery installations supporting U.S. data center operations and growth.”
The involvement of Tesla’s battery technology adds an intriguing layer, linking two of the world’s most prominent tech leaders—Zuckerberg and Musk—in the clean energy transition.
As data centers continue to drive unprecedented electricity load growth across the United States, projects like this one illustrate how hyperscalers are turning to strategic partnerships with traditional energy players and innovative storage solutions to meet both sustainability goals and reliability needs.
SpaceX has decided to stand down from what was supposed to be the first test launch of Starship’s v3 rocket tonight after a minor issue with a hydraulic pin delayed the flight once more.
The company scrubbed its first test flight of the upgraded Starship v3 on May 21 in the final minutes of the countdown. SpaceX CEO Elon Musk quickly took to social media platform X, explaining that a hydraulic pin on the launch tower’s “chopsticks” arm failed to retract properly.
Musk added that the company would fix the issue this evening. SpaceX will attempt another launch tomorrow night at 5:30 p.m. CT, 6:30 p.m. ET, and 3:30 p.m. PT.
The hydraulic pin holding the tower arm in place did not retract.
If that can be fixed tonight, there will be another launch attempt tomorrow at 5:30 CT. https://t.co/DJAdvDYQpH
— Elon Musk (@elonmusk) May 21, 2026
The countdown for Starship Flight 12 — featuring the taller and more capable V3 stack with Booster 19 and Ship 39 — had been progressing smoothly until the late-stage issue surfaced. The Mechazilla tower arm, designed to secure the vehicle on the pad and eventually catch returning boosters, could not complete its retraction sequence.
SpaceX teams immediately began troubleshooting the hydraulic system for an overnight repair.
Starship V3 introduces several significant upgrades over earlier versions. These include greater propellant capacity, more powerful Raptor 3 engines, larger grid fins, enhanced heat shielding, and an improved fuel transfer system.
We covered the changes that were announced just days ago by SpaceX:
SpaceX unveils sweeping Starship V3 upgrades ahead of May 19 launch
The changes are intended to increase payload performance, support higher flight rates, and advance the vehicle toward operational missions, including Starlink deployments, NASA Artemis lunar landings, and future crewed Mars flights. The debut flight from Starbase’s new Launch Pad 2 marked an important milestone in scaling up the fully reusable Starship system.
This stand-down highlights the intricate challenges of preparing the world’s most powerful rocket for flight. Despite extensive pre-launch checks, a single component in the ground support equipment can force a scrub.
The incident aligns with Starship’s proven iterative development approach. Previous test flights have encountered both successes and setbacks, each providing critical data that refines hardware and procedures. Some outlets may call some of these flights “failures,” when in reality, they are all opportunities for SpaceX to learn for the next attempt.
With V3, SpaceX aims to reduce ground-system dependencies and increase launch cadence to meet ambitious long-term goals.
NASA just gave SpaceX more crew missions because Boeing can’t certify
Elon Musk called it Epic: The full story of SpaceX’s Starship Flight 12
