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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Lifestyle
Tesla Semi hauls fresh Cybercab batch as Robotaxi era takes hold
A Tesla Semi was filmed hauling Cybercab units out of Giga Texas for the first time.
A Tesla Semi loaded with Cybercab units was recently filmed leaving Gigafactory Texas, marking what appears to be the first documented delivery run of Tesla’s autonomous two-seater. The footage shows multiple Cybercabs secured on a flatbed trailer being hauled by a production Tesla Semi, a truck rated for a gross combination weight of 82,000 lbs. The location is consistent with Giga Texas in Austin, where Cybercab production has been ramping since February 2026.
The sighting follows a wave of Cybercab activity at the Austin facility. In late April, drone operator Joe Tegtmeyer spotted approximately 60 Cybercabs parked in two organized groups in the factory’s outbound lot, the largest concentration observed to date. Units being staged in an outbound lot is a standard pre-delivery step, and the Semi footage is the logical next frame in that sequence.
En route with @tesla_semi pic.twitter.com/ZfuOjaeLH1
— Tesla Robotaxi (@robotaxi) May 7, 2026
This is not the first time Tesla has used its own Semi to move Tesla products. When the Semi was unveiled in 2017, Musk noted it would be used for Tesla’s own operations, and over the years Semi prototypes were spotted carrying cargo ranging from concrete weights to Tesla vehicles being delivered to consumers. In 2023, a Semi was photographed transporting a Cybertruck on a trailer ahead of that vehicle’s delivery launch.
The Cybercab itself was first revealed publicly at Tesla’s “We, Robot” event on October 10, 2024, at Warner Bros. Studios in Burbank, where 20 pre-production units gave attendees rides around the studio lot. Musk stated at the event that Tesla intends to produce the Cybercab before 2027. The first production unit rolled off the Giga Texas line on February 17, 2026, with Musk posting on X: “Congratulations to the Tesla team on making the first production Cybercab.”
Tesla’s annual production goal is 2 million Cybercabs per year once multiple factories reach full design capacity, with the company targeting a price under $30,000 per unit. Tesla has confirmed plans to expand its robotaxi service to seven cities in the first half of 2026, including Dallas, Houston, Phoenix, Miami, Orlando, Tampa, and Las Vegas, building on the unsupervised service already running in Austin. Musk has said he expects robotaxis to cover between a quarter and half of the United States by end of year.
Cybertruck
Tesla Cybertruck too safe for even Musk’s biggest critics to ignore
Krassenstein’s decision reveals that superior safety isn’t a partisan issue. For parents prioritizing family protection over personal or political grudges, the Cybertruck has become too safe to ignore.
The Tesla Cybertruck is an extremely polarizing vehicle because of its potential symbolism as a political stance instead of just a pickup truck — or at least that is what many would want you to believe.
Of course, the Cybertruck is an icon of Tesla culture, and it is one of those things that never has a middle ground: you love it, or you don’t.
But maybe there is an establishment of that “grey area” happening.
In a striking illustration of engineering triumph over political tribalism, prominent Elon Musk critic Brian Krassenstein has purchased a Tesla Cybertruck, openly citing its exceptional safety as the deciding factor for his family.
The announcement on X triggered predictable backlash, yet it underscores a growing reality: the Cybertruck’s safety credentials are proving impossible for even Musk’s fiercest detractors to dismiss.
I might get hate for this too but I bought a Cybertruck.
With a young family, safety was important and so is not polluting the atmosphere with $5 a gallon gasoline. pic.twitter.com/XJqFqR6O9r
— Brian Krassenstein (@krassenstein) May 6, 2026
Krassenstein, who has repeatedly clashed with Musk over issues ranging from content moderation and “wokeness” to public health figures, made no attempt to hide his reservations. In his May 6 post, he acknowledged the coming criticism: “I might get hate for this too but I bought a Cybertruck.”
He stressed that the decision had “nothing to do with Elon or politics,” pointing instead to practical advantages—his existing Tesla charger, eligibility for Full Self-Driving upgrades, a returning-owner discount, and crucially, the vehicle’s strong safety profile.
With gasoline prices hovering near $5 a gallon in some areas, he also highlighted the environmental benefit of switching from a polluting combustion engine.
The numbers, data, and awards validate Krassenstein’s choice.
The 2025 Cybertruck earned the Insurance Institute for Highway Safety’s (IIHS) elite Top Safety Pick+ award—the only pickup truck to achieve this highest rating. It delivered “Good” scores across every crashworthiness category, including the challenging updated moderate overlap front crash test, while excelling in crash avoidance and mitigation systems.
The National Highway Traffic Safety Administration (NHTSA) awarded it a perfect 5-star overall rating, with top marks in frontal, side, and rollover categories. No other pickup truck holds both distinctions simultaneously.
Tesla Cybertruck crash test rating situation revealed by NHTSA, IIHS
Beyond lab results, the Cybertruck’s stainless-steel exoskeleton and ultra-rigid structure have demonstrated remarkable real-world resilience. Owners have reported surviving high-speed collisions with minimal cabin intrusion.
In one widely discussed incident, a Cybertruck endured a 70 mph sideswipe on the interstate; the driver reported barely feeling the impact while the other vehicle was heavily damaged.
Tesla’s crash demonstrations and independent analyses consistently show how the vehicle’s design prioritizes occupant protection through a fortified passenger cell rather than traditional crumple zones, giving families superior safeguarding in many common crash scenarios.
The online pile-on following Krassenstein’s post focused on aesthetics, politics, and perceived hypocrisy rather than the data. Critics called the angular truck “ugly” or accused him of selling out.
Yet his purchase highlights an inconvenient truth for polarized discourse: when objective safety metrics—IIHS awards, NHTSA ratings, and documented crash performance—point decisively toward one vehicle, even Musk’s biggest critics are forced to confront its merits.
Krassenstein’s decision reveals that superior safety isn’t a partisan issue. For parents prioritizing family protection over personal or political grudges, the Cybertruck has become too safe to ignore.
SpaceXAI announced today that it had signed an agreement with Anthropic to give the company access to its Colossus 1 data center in Memphis, Tennessee.
It is a monumental deal as Anthropic will gain access to all of the compute at the plant, delivering more than 300 megawatts of power and over 220,000 NVIDIA GPUs within the month.
Anthropic’s Claude AI account on X announced the partnership:
“We’ve agreed to a partnership with SpaceX that will substantially increase our compute capacity. This, along with our other recent compute deals, means that we’ve been able to increase our usage limits for Claude Code and the Claude API.”
The company is also:
- Doubling Claude Code’s 5-hour rate limits for Pro, Max, and Team plans;
- Removing the peak hours limit reduction on Claude Code for Pro and Max plans; and
- Substantially raising its API rate limits for Opus models.
We’ve agreed to a partnership with @SpaceX that will substantially increase our compute capacity.
This, along with our other recent compute deals, means that we’ve been able to increase our usage limits for Claude Code and the Claude API.
— Claude (@claudeai) May 6, 2026
SpaceX also published its own release on the new agreement, noting that it is “the only organization with the launch cadence, mass-to-orbit economics, and constellation operations experience to make orbital compute a near-term engineering program rather than a research concept.”
CEO Elon Musk also commented on the partnership and shed light on intense meetings he had with senior members of Anthropic last week, stating, “nobody set on my evil detector.”
Same here.
By way of background for those who care, I spent a lot of time last week with senior members of the Anthropic team to understand what they do to ensure Claude is good for humanity and was impressed.
Everyone I met was highly competent and cared a great deal about…
— Elon Musk (@elonmusk) May 6, 2026
This has turned the argument that SpaceX is as much an AI company as a space exploration company into a very valid argument:
SpaceX is following in Tesla’s footsteps in a way nobody expected
Nevertheless, this is an incredibly valuable and important move in the grand scheme of things. AI scaling is fundamentally bottlenecked by compute, and demand for Claude has surged, bringing terrestrial power grids, land, and cooling operations hitting limits everywhere.
Anthropic has been aggressively signing multiple large-scale deals to be competitive in the space, including:
- Up to 5GW with Amazon
- 5GW with Google and Broadcom
- Strategic $30b Azure deal with Microsoft/NVIDIA
- $50b U.S. infrastructure investment with Fluidstack
Access to Colossus 1 gives Anthropic immediate relief on NVIDIA GPU capacity. For SpaceXAI, it turns its rapid buildout into revenue. It also showcases its ability to deliver at world-leading speed and scale.
Most importantly, it plants the seed that its much larger vision, orbital AI compute, is totally viable.
Starlink V3 satellites could enable SpaceX’s orbital computing plans: Musk
Within the month, Anthropic will begin using 100 percent of Colossus 1’s compute, directly expanding capacity for Claude Pro and Max subscribers and the API. This means fewer limits, faster responses, and support for heavier workloads.
In the long term, meaning 2026 and beyond, there will be a continued rollout of other multi-GW deals Anthropic has signed, and an early exploration of orbital compute with SpaceXAI.
Tesla Semi hauls fresh Cybercab batch as Robotaxi era takes hold
Tesla Cybertruck too safe for even Musk’s biggest critics to ignore
