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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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Tesla Full Self-Driving is set to get a major fix with pothole avoidance, a feature that CEO Elon Musk said recently was “coming soon.” The feature has been included within the FSD v14 release notes for some time as an upcoming improvement.
Potholes come in all shapes and sizes, but one thing is universal about them, and that is the fact that every driver wants to avoid them. Driving into or over a pothole can cause tire and wheel damage, alignment issues, and even, in some more severe instances, injury to occupants or major damage to a vehicle in despair.
Tesla Cybercab uses a unique strategy for picking up the right rider
Musk said late last night in a post that pothole avoidance while utilizing the Full Self-Driving suite is “coming soon.”
Coming soon
— Elon Musk (@elonmusk) August 31, 2026
Full Self-Driving, even in its most recent and robust forms, still has its shortcomings. While the suite has performed exceptionally well with avoiding on-road obstacles like cardboard boxes, horse droppings, car parts, and other debris, it still seems to struggle with recognizing certain things.
Potholes and other abrupt changes in a road’s layout are things that FSD still tends to struggle with. Perhaps the suite’s 3D modeling is still in need of some additional data or some sort of script that will help it to avoid a potentially destructive pothole or bump in the road that would be easily recognizable by the human eye.
Musk has mentioned pothole avoidance for some time, with the initial idea coming in April 2019 when an owner first requested the feature. Musk said that Tesla would “definitely” develop pothole avoidance.
In August 2020, Musk said Tesla was in the process of labeling bumps and potholes so cars can either slow down or steer around them altogether.
Tesla to utilize micro maps for pothole-detection in future update
Avoiding major disturbances in the road is a necessary feature for Full Self-Driving to have, especially as Tesla is working toward a fully autonomous program that will eventually allow every occupant in the vehicle to sleep, work, or enjoy leisure time while traveling.
That truly begins this week with the launch of Cybercab on Thursday.
Elon Musk
Elon Musk says he knows how to save Earth for a billion years
Elon Musk says sentient AI satellites launched from the Moon could keep Earth livable forever.
Elon Musk spent part of his weekend describing a plan to keep the planet livable for roughly a billion years, and it starts with satellites that can think for themselves.
In a post on X, Musk argued that swapping fossil fuels for solar and wind power will not be enough to protect humanity from what he called extremely severe extinction events, the kind that occur roughly every 100 million years. His fix is what he called sentient satellites, or solar-powered satellites, controlled by AI, that would sit in a fixed spot between Earth and the Sun after being launched off the Moon using a giant electromagnetic catapult instead of rockets.
The satellites’ onboard AI would make continuous, small adjustments rather than waiting on human instructions. The mass driver is Musk’s proposed way of getting the raw material there cheaply by using an electromagnetic launch track built on the Moon, where lower gravity and no atmosphere make it far easier to fling cargo into space than it is from Earth.
But we do need to act much faster than that if people still want to live where the beach is today. We have about 50 years or so to take action, which should be more than enough time for the space satellites to solve any heating problems. https://t.co/xhrVQALwQw
— Elon Musk (@elonmusk) August 30, 2026
Musk shared a Grok generated estimate suggesting roughly 5 percent of Florida’s land, or about 1.68 million acres, could face regular flooding by 2070 under a high sea level rise scenario, and said humanity has about 50 years to act before coastal living looks very different than it does today.
This is not the first time Musk has floated the idea. He raised a similar concept in November, describing a solar powered AI satellite constellation that could make tiny adjustments to incoming sunlight to fine tune Earth’s temperature. Musk has also tied planetary risk to his broader vision at SpaceX, where his compensation package is explicitly linked to establishing a self-sustaining Mars colony, one he has described as an insurance policy against the kind of extinction event he referenced this weekend, and where he has said humans could set foot within five to seven years.
Elon Musk
OpenAI cites distrust of SpaceX in decision to drop Cursor partnership
OpenAI will cut SpaceX-owned Cursor’s model access in November, citing Musk’s history of broken contracts.
OpenAI, the company behind ChatGPT, announced late Friday that it is ending its partnership with Cursor, cutting off the coding tool’s access to its models on November 12. The move comes two weeks after SpaceX completed its $60 billion acquisition of Cursor’s parent company, Anysphere, folding the popular AI coding assistant into Elon Musk’s growing SpaceXAI division.
In a post on its website, OpenAI said the decision came down to trust, not technology. “We cannot be confident that SpaceX will use our technology within our terms of service, based on our experience with Elon Musk’s companies violating contracts,” the company wrote. OpenAI pointed to two specific incidents: X, now part of SpaceX, allegedly breaking the terms of an existing OpenAI contract after Musk bought Twitter.
That lawsuit is the backdrop for all of this. Musk cofounded OpenAI in 2015, left the board in 2018, and sued Sam Altman and Greg Brockman in 2024, arguing they abandoned the company’s nonprofit mission for profit. A federal jury sided with OpenAI in May, finding Musk waited too long to sue rather than ruling on the merits of his claims. Musk said at the time he would appeal to the Ninth Circuit, calling the outcome a “calendar technicality” rather than a real judgment.
SpaceX’s interest in Cursor predates that verdict by weeks. The company first struck a deal with Cursor in April, securing an option to acquire it for $60 billion or pay $10 billion for joint development work instead. As Teslarati reported at the time, the logic was straightforward: Cursor was paying retail prices to Anthropic and OpenAI, two of its most direct competitors, every time a developer used its product, while SpaceX had idle capacity on its Colossus supercomputer, roughly the equivalent of a million Nvidia H100 GPUs, that Cursor could use to train its own models instead. SpaceX exercised the option in June, days after its own IPO, and the deal closed in mid-August.
Once it closed, Musk moved fast. On an all-hands call with more than 1,000 Cursor employees, he reportedly told staff that SpaceXAI’s Grok was playing catchup in the AI race, unlike Tesla and SpaceX in their own markets, and singled out Anthropic as the company to catch. Cursor CEO Michael Truell now reports directly to Musk inside SpaceXAI.
Losing OpenAI’s models leaves Cursor leaning harder on Anthropic’s Claude, which has its own compute agreement with SpaceX, and on Cursor’s in-house Composer model, the one SpaceX’s compute was supposed to accelerate in the first place. OpenAI framed the November deadline as maximum notice under its contract, and said it wants to “go above and beyond” to help developers through the transition. Whether Anthropic makes the same call is now the open question in AI coding.
Tesla is fixing Full Self-Driving’s pothole problem
Elon Musk says he knows how to save Earth for a billion years
