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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News
Honda gives up on all-EV future: ‘Not realistic’
Mibe believes the demand for its gas vehicles is certainly strong enough and has changed “beyond expectations.” As many drivers went for EVs a few years back, hybrids are becoming more popular for consumers as they offer the best of both worlds.
Honda has given up on a previous plan to completely changeover to EVs by 2040, a new report states. The company’s CEO, Toshihiro Mibe, said that the idea is “not realistic.”
Mibe believes the demand for its gas vehicles is certainly strong enough and has changed “beyond expectations.” As many drivers went for EVs a few years back, hybrids are becoming more popular for consumers as they offer the best of both worlds.
Mibe said (via Motor1):
“Because of the uncertainty in the business environment and also the customer demand, is changing beyond our expectation and, therefore, we have judged that it’ll be difficult to achieve. That ratio [100-percent electric in 2040] is not realistic as of now. We have withdrawn this target.”
Instead of going all-electric, Honda still wants to oblige by its hopes to be net carbon neutral by 2050. It will do this by focusing on those popular hybrid powertrains, planning to launch 15 of them by March 2030.
Honda will invest 4.4 trillion yen, or almost $28 billion, to build hybrid powertrains built around four and six-cylinder gas engines.
There are so many companies abandoning their all-electric ambitions or even slowing their roll on building them so quickly. Ford, General Motors, Mercedes, and Nissan have all retreated from aggressive EV targets by either cancelling, delaying, or pausing the development of electric models.
Hyundai’s 2030 targets rely on mixed offerings of electric, hybrid & hydrogen vehicles
Early-decade pledges from multiple brands proved overly ambitious as infrastructure lags, battery costs remain high in some markets, and many buyers prefer hybrids for their convenience and range. Toyota has long championed hybrids, while others have quietly extended internal-combustion timelines.
For Honda—historically known for reliable gasoline engines—this shift leverages its core strengths while buying time to refine electric technology. Whether the hybrid-heavy strategy will protect market share in an increasingly competitive landscape remains to be seen, but one thing is clear: the gas engine is far from dead at Honda, unfortunately.
Elon Musk
Delta Airlines rejects Starlink, and the reason will probably shock you
In a pointed exchange on X, Elon Musk defended SpaceX’s uncompromising approach to Starlink’s in-flight internet service, explaining why Delta Air Lines walked away from a deal.
SpaceX frontman Elon Musk explained on Wednesday why commercial airline Delta got cold feet over offering Starlink for stable internet on its flights — and the reason will probably shock you.
In a pointed exchange on X, Elon Musk defended SpaceX’s uncompromising approach to Starlink’s in-flight internet service, explaining why Delta Air Lines walked away from a deal.
Delta rejected Starlink because it insisted on routing all connectivity through its branded “Delta Sync” portal rather than allowing a simple Starlink experience.
Instead, the airline partnered with Amazon’s Project Kuiper—rebranded as Amazon Leo—for high-speed Wi-Fi on up to 500 aircraft, with rollout targeted for 2028. At the time of the announcement, Kuiper had roughly 300 satellites in orbit, while Starlink operated more than 10,400.
The use of the “Delta Sync” portal would not work for SpaceX, as Musk went on to say that:
“SpaceX requires that there be no annoying ‘portal’ to use Starlink. Starlink WiFi must just work effortlessly every time, as though you were at home. Delta wanted to make it painful, difficult and expensive for their customers. Hard to see how that is a winning strategy.”
Musk doubled down in a follow-up post:
“Yes, SpaceX deliberately accepted lower revenue deals with airlines in exchange for making Starlink super easy to use and available to all passengers.”
Not exactly. SpaceX requires that there be no annoying “portal” to use Starlink.
Starlink WiFi must just work effortlessly every time, as though you were at home.
Delta wanted to make it painful, difficult and expensive for their customers. Hard to see how that is a winning…
— Elon Musk (@elonmusk) May 13, 2026
SpaceX has structured its airline agreements to prioritize zero-friction access—no captive portals, no SkyMiles logins, no paywalls or ads blocking basic connectivity.
While this means forgoing higher-margin deals that would let carriers monetize the service more aggressively, it ensures Starlink feels like home broadband at 35,000 feet. Passengers on partner airlines such as United, Qatar Airways, and Air France have already praised the service for enabling seamless video calls, streaming, and work mid-flight without interruptions.
Delta’s choice reflects a different philosophy. By keeping Wi-Fi behind its Delta Sync ecosystem, the airline aims to drive loyalty program engagement and control the digital passenger journey. Yet, critics argue this short-term control comes at the expense of immediate competitiveness.
Airlines already installing Starlink are pulling ahead in customer satisfaction surveys, while Delta passengers face years of reliance on slower, legacy systems until Leo launches.
SpaceX’s decision to trade revenue for simplicity will pay off in the longer term, as Starlink is already positioning itself as the default high-speed option for carriers that value passenger satisfaction over incremental fees.
Musk’s focus on creating not only a great service but also a reasonable user experience highlights SpaceX’s prowess with Starlink as it continues to expand across new partners and regions.
News
Tesla gathers 93,000 FSD miles in a country where FSD isn’t approved – here’s how
Tesla has quietly logged an impressive 93,000 miles (roughly 150,000 km) of autonomous driving at its Giga Berlin factory—using Full Self-Driving (FSD) in a country where the technology remains unavailable to consumers on public roads.
Tesla has gathered 93,000 Full Self-Driving miles in a country where Full Self-Driving is not even approved. Here’s how.
Tesla has quietly logged an impressive 93,000 miles (roughly 150,000 km) of autonomous driving at its Giga Berlin factory—using Full Self-Driving (FSD) in a country where the technology remains unavailable to consumers on public roads.
The milestone, revealed alongside news that Giga Berlin has now built 750,000 Model Y vehicles, highlights how Tesla is putting its AI to work in one of the most controlled environments imaginable: it’s own factory floor.
Every Model Y that rolls off the final assembly line at Giga Berlin doesn’t need a human driver to reach the outbound lot. Instead, the freshly built vehicles engage FSD and navigate themselves across the factory campus.
The Tesla Model Ys rolling off the production line at Giga Berlin have now driven themselves on FSD a combined 93,000 miles from the end of the production line to the outbound lot. https://t.co/6RhL3W4q4p pic.twitter.com/DOKKHUcSSL
— Sawyer Merritt (@SawyerMerritt) May 11, 2026
The route—from the end of the production line through marked internal pathways to the staging area where cars await delivery or export—is entirely on private property. No public roads, no mixed traffic, and no regulatory hurdles for on-road autonomous operation.
It’s a closed-loop system: wide lanes, predictable layouts, minimal pedestrians, and consistent conditions that make it one of the simplest proving grounds for the software.
A short factory tour video shared by Tesla Manufacturing shows General Assembly team member Jan explaining the process. Gesturing beside a glossy black Model Y still wearing its protective wrap, he notes the cumulative distance the fleet has covered autonomously.
Tesla Giga Berlin seems to be using FSD Unsupervised to move Model Y units
The cars handle the short drive flawlessly, freeing up workers who would otherwise spend hours shuttling vehicles manually. For a high-volume plant like Giga Berlin, the time and labor savings add up quickly. Even small gains in cycle time per car can reclaim valuable space in the outbound lot and streamline logistics.
This internal deployment serves multiple purposes. First, it delivers zero-cost validation data. Each factory run exposes FSD to real-world physics—acceleration, steering precision, obstacle avoidance—in a repeatable setting far safer than public testing.
Second, it demonstrates the system’s readiness at scale. If FSD can reliably move thousands of brand-new cars without intervention inside a busy factory, it underscores the robustness of the vision-based, end-to-end neural network Tesla has been refining.
Critics often point to Europe’s cautious regulatory stance on unsupervised autonomy, yet Tesla has turned that limitation into an advantage. While owners in Germany still cannot activate consumer FSD on highways or city streets, the software is already proving its worth behind the factory gates.
The 93,000 miles represent not just internal efficiency gains but a subtle flex: the cars are manufactured ready to navigate autonomously, at least in the bounds of the factory. It’s a big feather in the cap of FSD, even if regulators have yet to green-light broader use.
As Giga Berlin continues ramping output, expect this autonomous logistics loop to grow. What began as a practical workaround for moving finished vehicles has quietly become one of the most compelling real-world showcases of FSD’s potential—right in the heart of regulated Europe. Tesla isn’t waiting for approval to perfect its autonomy; it’s already driving the future, one factory mile at a time.
Honda gives up on all-EV future: ‘Not realistic’
Delta Airlines rejects Starlink, and the reason will probably shock you
