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 is quietly becoming the U.S. Military’s only reliable rocket
Space Force drops ULA for SpaceX on GPS launch after Vulcan rocket anomaly investigation halts flights.
The U.S. Space Force announced today it is switching an upcoming GPS III satellite launch from United Launch Alliance’s Vulcan rocket to a SpaceX Falcon 9, a move that is as much a reflection of Vulcan’s mounting problems as it is a validation of SpaceX’s growing dominance in national security space launch. The GPS III Space Vehicle 09, originally contracted to fly on Vulcan this month, will now target a late April liftoff on Falcon 9, marking the fourth consecutive GPS III satellite the Space Force has moved to SpaceX after contracts were originally awarded to ULA.
The immediate trigger is a solid rocket motor anomaly that occurred on February 12 during Vulcan’s USSF-87 mission. Although the payloads reached orbit and ULA declared the mission successful, the company characterized the malfunction as a “significant performance anomaly” and has since paused all military launches on Vulcan pending a root cause investigation.
“With this change, we are answering the call for rapid delivery of advanced GPS capability while the Vulcan anomaly investigation continues,” said Systems Delta 81 Commander Col. Ryan Hiserote. “We are once again demonstrating our team’s flexibility and are fully committed to leverage all options available for responsive and reliable launch for the Nation.”
The broader reality is that SpaceX’s reliability record and launch cadence have made it the path of least resistance for the Pentagon, and bodes well with Elon Musk’s plans to IPO SpaceX sometime this year. Its Falcon 9 is the most flight-proven rocket in history, and the Space Force’s Rapid Response Trailblazer program was specifically designed to enable exactly this kind of provider swap for GPS missions, and effectively building SpaceX’s flexibility into the national security launch architecture by design.
For ULA, the stakes are existential. The company entered 2026 with aspirations of finally turning a corner after years of Vulcan delays, with interim CEO John Elbon pointing to a backlog of over 80 missions as reason for optimism. Meanwhile, SpaceX’s contracts with the Space Force have given it a formal pathway to take on even more national security launches going forward.
The significance of today’s announcement extends beyond one satellite swap. It reinforces that America’s most critical space infrastructure, including GPS, missile warning, and beyond, is increasingly dependent on a single commercial provider.
News
Tesla Full Self-Driving gets huge breakthrough on European expansion
All documentation for UN R-171 approval and Article 39 exemptions has been submitted, with RDW now conducting its internal review. Approval in the Netherlands is expected on April 10, shifted from the original March 20 target, following 18 months of rigorous collaboration.
Tesla Full Self-Driving has gotten a huge breakthrough as the company is still planning big things for its European expansion, hoping to bring the impressive platform into the continent after years of attempts.
Tesla Europe has announced a major breakthrough: the company has officially completed the final vehicle testing phase for Full Self-Driving (Supervised) in partnership with the Dutch vehicle authority RDW.
All documentation for UN R-171 approval and Article 39 exemptions has been submitted, with RDW now conducting its internal review. Approval in the Netherlands is expected on April 10, shifted from the original March 20 target, following 18 months of rigorous collaboration.
Together with RDW, we have officially completed the final vehicle testing phase for Full Self-Driving (Supervised) and have submitted all documentation required for the UN R-171 approval + Article 39 exemptions. The RDW team is now reviewing the documentation and test results…
— Tesla Europe, Middle East & Africa (@teslaeurope) March 20, 2026
The process has been exhaustive. Tesla said it has logged more than 1.6 million kilometers of FSD (Supervised) testing on European roads, conducted over 13,000 customer ride-alongs, executed 4,500+ track test scenarios, produced thousands of pages of documentation covering 400+ compliance requirements, and completed dozens of independent safety studies.
The company expressed pride in the partnership and anticipation of bringing the feature to “patient EU customers” soon after approval.
Europe’s regulatory landscape has presented steep challenges for Tesla’s advanced driver-assistance systems. The EU enforces some of the world’s strictest safety standards under the United Nations Economic Commission for Europe framework, particularly UN Regulation 171 on Driver Control Assistance Systems.
Unlike the more permissive U.S. environment, European rules historically limited system-initiated maneuvers, required constant driver supervision, and demanded country-by-country or bloc-wide exemptions. Tesla faced repeated delays, with initial February 2026 targets pushed back amid RDW’s insistence that safety, not public or corporate pressure, would govern timelines.
Tesla Europe builds momentum with expanding FSD demos and regional launches
A former Tesla executive warned in 2024 that certain regulatory elements could slip to 2028, highlighting bureaucratic hurdles, extensive audits, and the need for harmonized data privacy and liability frameworks across fragmented member states.
Yet progress is accelerating. Amendments to UN R-171 adopted in 2025 now permit hands-free highway lane changes and other automated features, clearing technical barriers. Once the Netherlands grants national approval, mutual recognition allows other EU countries to adopt it immediately, potentially leading to an EU-wide rollout by summer 2026.
This European breakthrough is part of Tesla’s broader push into foreign markets. Full Self-Driving (Supervised) is already live in the United States and expanding rapidly.
In China, where partial approvals exist, CEO Elon Musk has targeted full rollout around the same February–March 2026 window, despite lingering data-security reviews.
Additional markets, including the UAE, are slated for early 2026 launches. These expansions are critical as Tesla seeks to monetize software amid softening EV demand globally.
For European Tesla owners, the wait appears nearly over. Approval would unlock advanced autonomy features that have long been available elsewhere, marking a pivotal step in Tesla’s global autonomy ambitions and reinforcing its commitment to navigating complex international regulations.
Elon Musk
Tesla’s $2.9 billion bet: Why Elon Musk is turning to China to build America’s solar future
Tesla looks to bring solar manufacturing to the US, with latest $2.9 billion bet to acquire Chinese solar equipment.
Tesla is reportedly in talks to purchase $2.9 billion worth of solar manufacturing equipment from a group of Chinese suppliers, including Suzhou Maxwell Technologies, which is the world’s largest producer of screen-printing equipment used in solar cell production. According to Reuters sources, the equipment is expected to be delivered before autumn and shipped to Texas, where Tesla plans to anchor its next phase of domestic solar production.
The move is a direct extension of a vision Elon Musk has been building for months. At the World Economic Forum in Davos this past January, Musk announced that both Tesla and SpaceX were independently working to establish 100 gigawatts of annual solar manufacturing capacity inside the United States. Days later, on Tesla’s Q4 2025 earnings call, he made the ambition concrete: “We’re going to work toward getting 100 GW a year of solar cell production, integrating across the entire supply chain from raw materials all the way to finished solar panels.”
Job postings on Tesla’s website reflect that same target, with language explicitly calling for 100 GW of “solar manufacturing from raw materials on American soil before the end of 2028.”
Tesla job listing for Staff Manufacturing Development Engineer, Solar Manufacturing
The urgency behind the latest solar manufacturing target is rooted in a set of rapidly emerging pressures related to AI and Tesla’s own energy business. U.S. power consumption hit its second consecutive record high in 2025 and is projected to climb further through 2026 and 2027, driven largely by the explosion in AI data centers and the broader electrification of transportation. Tesla’s own energy division, which produces the Megapack utility-scale battery storage system, has been growing rapidly, and solar supply is a critical companion component for the business to scale. Musk has argued that solar is not just a clean energy option but the only one that makes economic sense at the scale AI infrastructure demands.
Tesla lands in Texas for latest Megapack production facility
Ironically, the path to domestic solar independence currently runs through China. Sort of.
Despite Tesla’s stated push to localize its supply chain, mirrored recently by the company’s plan for a $4.3 billion LFP battery manufacturing partnership with LG Energy Solution in Michigan, Tesla still relies on China-based suppliers to keep its cost structure intact.
The $2.9 billion equipment deal underscores a tension Musk himself acknowledged at Davos: “Unfortunately, in the U.S. the tariff barriers for solar are extremely high and that makes the economics of deploying solar artificially high, because China makes almost all the solar.” Building the factory in America requires buying the machinery from the country Tesla is trying to reduce its dependence on.
Tesla named by U.S. Gov. in $4.3B battery deal for American-made cells
The regulatory pathway adds another layer of complexity. Suzhou Maxwell has been seeking export approval from China’s commerce ministry, and it remains unclear how quickly that clearance will come. Still, the market has already reacted, with shares in the Chinese firms reportedly involved in the talks surged more than 7% following the Reuters report that broke the story.
Whether Tesla can hit its 2028 target of 100GW of solar manufacturing remains an open question. Though that scale may seem staggering, especially in such a short timeframe, we know that Musk has a documented history of “always pulling it off” in the face of ambitious deadlines that may slip. But, rest assured – it’ll get done.
SpaceX is quietly becoming the U.S. Military’s only reliable rocket
Tesla Full Self-Driving gets huge breakthrough on European expansion
