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.
I’d love to hear from you! If you have any comments, concerns, or questions, please email me at joey@teslarati.com. You can also reach me on Twitter @KlenderJoey, or if you have news tips, you can email us at tips@teslarati.com.
Elon Musk
Elon Musk’s X will start using a Tesla-like software update strategy
The initiative seems designed to accelerate updates to the social media platform, while maintaining maximum transparency.
Elon Musk’s social media platform X will adopt a Tesla-esque approach to software updates for its algorithm.
The initiative seems designed to accelerate updates to the social media platform, while maintaining maximum transparency.
X’s updates to its updates
As per Musk in a post on X, the social media company will be making a new algorithm to determine what organic and advertising posts are recommended to users. These updates would then be repeated every four weeks.
“We will make the new 𝕏 algorithm, including all code used to determine what organic and advertising posts are recommended to users, open source in 7 days. This will be repeated every 4 weeks, with comprehensive developer notes, to help you understand what changed,” Musk wrote in his post.
The initiative somewhat mirrors Tesla’s over-the-air update model, where vehicle software is regularly refined and pushed to users with detailed release notes. This should allow users to better understand the details of X’s every update and foster a healthy feedback loop for the social media platform.
xAI and X
X, formerly Twitter, has been acquired by Elon Musk’s artificial intelligence startup, xAI last year. Since then, xAI has seen a rapid rise in valuation. Following the company’s the company’s upsized $20 billion Series E funding round, estimates now suggest that xAI is worth tens about $230 to $235 billion. That’s several times larger than Tesla when Elon Musk received his controversial 2018 CEO Performance Award.
As per xAI, the Series E funding round attracted a diverse group of investors, including Valor Equity Partners, Stepstone Group, Fidelity Management & Research Company, Qatar Investment Authority, MGX, and Baron Capital Group, among others. Strategic partners NVIDIA and Cisco Investments also continued support for building the world’s largest GPU clusters.
News
Tesla FSD Supervised wins MotorTrend’s Best Driver Assistance Award
The decision marks a notable reversal for the publication from prior years, with judges citing major real-world improvements that pushed Tesla’s latest FSD software ahead of every competing ADAS system.
Tesla’s Full Self-Driving (Supervised) system has been named the best driver-assistance technology on the market, earning top honors at the 2026 MotorTrend Best Tech Awards.
The decision marks a notable reversal for the publication from prior years, with judges citing major real-world improvements that pushed Tesla’s latest FSD software ahead of every competing ADAS system. And it wasn’t even close.
MotorTrend reverses course
MotorTrend awarded Tesla FSD (Supervised) its 2026 Best Tech Driver Assistance title after extensive testing of the latest v14 software. The publication acknowledged that it had previously criticized earlier versions of FSD for erratic behavior and near-miss incidents, ultimately favoring rivals such as GM’s Super Cruise in earlier evaluations.
According to MotorTrend, the newest iteration of FSD resolved many of those shortcomings. Testers said v14 showed far smoother behavior in complex urban scenarios, including unprotected left turns, traffic circles, emergency vehicles, and dense city streets. While the system still requires constant driver supervision, judges concluded that no other advanced driver-assistance system currently matches its breadth of capability.
Unlike rival systems that rely on combinations of cameras, radar, lidar, and mapped highways, Tesla’s FSD operates using a camera-only approach and is capable of driving on city streets, rural roads, and freeways. MotorTrend stated that pure utility, the ability to handle nearly all road types, ultimately separated FSD from competitors like Ford BlueCruise, GM Super Cruise, and BMW’s Highway Assistant.
High cost and high capability
MotorTrend also addressed FSD’s pricing, which remains significantly higher than rival systems. Tesla currently charges $8,000 for a one-time purchase or $99 per month for a subscription, compared with far lower upfront and subscription costs from other automakers. The publication noted that the premium is justified given FSD’s unmatched scope and continuous software evolution.
Safety remained a central focus of the evaluation. While testers reported collision-free operation over thousands of miles, they noted ongoing concerns around FSD’s configurable driving modes, including options that allow aggressive driving and speeds beyond posted limits. MotorTrend emphasized that, like all Level 2 systems, FSD still depends on a fully attentive human driver at all times.
Despite those caveats, the publication concluded that Tesla’s rapid software progress fundamentally reshaped the competitive landscape. For drivers seeking the most capable hands-on driver-assistance system available today, MotorTrend concluded Tesla FSD (Supervised) now stands alone at the top.
News
Elon Musk’s Grokipedia surges to 5.6M articles, almost 79% of English Wikipedia
The explosive growth marks a major milestone for the AI-powered online encyclopedia, which was launched by Elon Musk’s xAI just months ago.
Elon Musk’s Grokipedia has grown to an impressive 5,615,201 articles as of today, closing in on 79% of the English Wikipedia’s current total of 7,119,376 articles.
The explosive growth marks a major milestone for the AI-powered online encyclopedia, which was launched by Elon Musk’s xAI just months ago. Needless to say, it would only be a matter of time before Grokipedia exceeds English Wikipedia in sheer volume.
Grokipedia’s rapid growth
xAI’s vision for Grokipedia emphasizes neutrality, while Grok’s reasoning capabilities allow for fast drafting and fact-checking. When Elon Musk announced the initiative in late September 2025, he noted that Grokipedia would be an improvement to Wikipedia because it would be designed to avoid bias.
At the time, Musk noted that Grokipedia “is a necessary step towards the xAI goal of understanding the Universe.”
Grokipedia was launched in late October, and while xAI was careful to list it only as Version 0.1 at the time, the online encyclopedia immediately earned praise. Wikipedia co-founder Larry Sanger highlighted the project’s innovative approach, noting how it leverages AI to fill knowledge gaps and enable rapid updates. Netizens also observed how Grokipedia tends to present articles in a more objective manner compared to Wikipedia, which is edited by humans.
Elon Musk’s ambitious plans
With 5,615,201 total articles, Grokipedia has now grown to almost 79% of English Wikipedia’s article base. This is incredibly quick, though Grokipedia remains text-only for now. xAI, for its part, has now updated the online encyclopedia’s iteration to v0.2.
Elon Musk has shared bold ideas for Grokipedia, including sending a record of the entire knowledge base to space as part of xAI’s mission to preserve and expand human understanding. At some point, Musk stated that Grokipedia will be renamed to Encyclopedia Galactica, and it will be sent to the cosmos.
“When Grokipedia is good enough (long way to go), we will change the name to Encyclopedia Galactica. It will be an open source distillation of all knowledge, including audio, images and video. Join xAI to help build the sci-fi version of the Library of Alexandria!” Musk wrote, adding in a later post that “Copies will be etched in stone and sent to the Moon, Mars and beyond. This time, it will not be lost.”
Elon Musk’s X will start using a Tesla-like software update strategy
Tesla FSD Supervised wins MotorTrend’s Best Driver Assistance Award
