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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 Roadster gets an update, but not the one fans were looking for
Tesla has quietly filed a new trademark application for its next-generation Roadster, giving enthusiasts their first official glimpse of fresh branding for the long-teased electric supercar.
Tesla has been slow to show its hand regarding the massive project that is the Roadster, but it is now coming forth with a new update.
However, it is probably not the one fans were looking for.
Tesla has quietly filed a new trademark application for its next-generation Roadster, giving enthusiasts their first official glimpse of fresh branding for the long-teased electric supercar.
The February 3 filing includes an inverted triangular badge with the word “ROADSTER” centered above four vertical lines that, according to the application, represent “speed, propulsion, heat, or wind.”
A sleek, angular wordmark and a minimalist curved-line silhouette hinting at the car’s aerodynamic shape round out the trio of marks.
I found something cool. Tesla has filed a new trademark application for its next-generation Roadster. It could be the new Roadster logo/badge.
The filing says the lines depict speed, propulsion, heat or wind.
(I took the liberty of making the logo red. Trademark filings are… pic.twitter.com/W9JSDwTRL7
— Sawyer Merritt (@SawyerMerritt) May 6, 2026
For a program that began with Elon Musk’s 2017 reveal, this is tangible forward motion. The original Roadster proved EVs could be thrilling; the next generation aims higher, with promises of sub-two-second 0-60 mph acceleration and, in its most extreme configuration, optional SpaceX cold-gas thrusters for rocket-like thrust.
The new trademarks suggest Tesla is now locking down the visual identity that will accompany those headline specs, as well as a small hint that maybe we’re finally getting close. However, the company has not revealed any progress on the vehicle itself or its specs to the public.
It continues to tease with developments like this one.
That said, the update lands with a familiar bittersweet note. Fans have waited nearly a decade since the initial unveiling. Production was once eyed for 2020, then 2021, then later still. In the intervening years, Tesla has delivered the Model Y, Cybertruck, Semi, and major autonomy advances while scaling its energy business.
The Roadster has taken a back seat, and the delays have been genuinely disappointing. Many longtime supporters have grown frustrated watching renderings and hearsay while other marques roll out ever-faster electric sports cars.
Yet, the Roadster program itself still sparks genuine excitement. It represents the purest expression of Tesla’s “accelerate the world’s transition to sustainable energy” mission—pushing performance boundaries to prove EVs can outperform anything with an engine.
The new branding, modest as it is, keeps that promise alive. It tells owners and prospective buyers that Tesla hasn’t forgotten the car that started it all.
No one would blame fans for wanting more than a logo right now. But in an industry where many concepts never leave the drawing board, the fact that Tesla continues to invest in and protect the Roadster’s identity is reason for measured optimism.
The wait has tested patience, but when the next-generation Roadster finally arrives, the new badge may well adorn one of the most exciting cars ever built. For those who have followed the journey this far, that payoff still feels worth it.
News
Tesla gets a massive order for the Semi: 370 units and $100M
WattEV, a leading provider of electric freight operations and charging infrastructure in the United States, has announced one of the largest deployments of electric Class 8 trucks in California history: an order for 370 Tesla Semi vehicles.
Tesla just got a massive order for the Semi, and it is its largest by a long shot.
WattEV, a leading provider of electric freight operations and charging infrastructure in the United States, has announced one of the largest deployments of electric Class 8 trucks in California history: an order for 370 Tesla Semis.
Valued at approximately $100 million, this marks the state’s biggest single electric truck order to date and signals accelerating momentum for zero-emission long-haul freight.
Credit: Tesla
Deliveries are set to begin with the first 50 Tesla Semis in 2026, with the full fleet operational by the end of 2027. More than 300 of these trucks will support a joint program with the Port of Oakland, helping electrify drayage and regional freight routes. The initiative aligns with California’s ambitious goals to transition to carbon-neutral freight operations.
Salim Youssefzadeh, CEO of WattEV, said at the annual ACT Expo industry event that the Semi was the easiest choice:
“We selected the Tesla Semi based on cost, performance, and availability after issuing a public request for proposals…With the Tesla Semi now entering mass production and drawing strong reviews from fleet operators nationwide, WattEV’s vertically integrated model – combining vehicle deployment, megawatt-class charging infrastructure, and full-service leasing – offers a turn-key path for carriers without any capital risk.”
Critical to the rollout are new Megawatt Charging System (MCS) hubs in Oakland, Fresno, Stockton, and Sacramento. These stations will deliver up to 300 miles of range in roughly 30 minutes—comparable to a traditional diesel fill-up. The Oakland depot, where WattEV recently broke ground, will serve as a cornerstone for northern and central California corridors, connecting ports to inland hubs and beyond.
This deployment builds on WattEV’s existing experience. The company has already logged millions of electric miles in Southern California, including early Tesla Semi deployments at the Ports of Long Beach and Los Angeles. By combining high-efficiency electric trucks with strategically placed fast-charging depots, WattEV aims to prove that battery-electric long-haul trucking can match—or exceed—diesel economics while slashing emissions.
The order arrives as Tesla ramps up Semi production at its Nevada factory, targeting higher volumes in 2026. Fleet operators nationwide have praised the Semi’s real-world performance, including strong torque, low operating costs, and advanced safety features. For California, the project supports air quality improvements around ports and highways while demonstrating scalable infrastructure for heavy-duty electrification.
Industry observers see this as a pivotal step toward broader adoption. With diesel trucks facing rising fuel and regulatory costs, turnkey electric solutions like WattEV’s could accelerate the shift. As the first 50 Semis hit the road in 2026, they will not only move freight but also help build the charging network that paves the way for even larger fleets.
This landmark order underscores Tesla’s growing footprint in commercial trucking and California’s leadership in sustainable transportation. For WattEV and its partners, it’s more than a vehicle purchase—it’s the foundation of a zero-emission freight network connecting Northern and Central California.
News
Tesla begins factoring international designs in Full Self-Driving visualization
Tesla has begun incorporating region-specific vehicle designs into its Full Self-Driving (FSD) visualization system, marking a quiet but meaningful step toward global readiness. In software update 2026.14, released as part of the Spring Update, European Tesla owners are now seeing flat-fronted, cab-over European-style semi-trucks rendered accurately on their center displays.
Tesla has begun factoring international designs into its Full Self-Driving (Supervised) visualizations, marking a tremendous step in how the company plans to roll out its driver assistance tech in areas outside North America.
Tesla has begun incorporating region-specific vehicle designs into its Full Self-Driving (FSD) visualization system, marking a quiet but meaningful step toward global readiness. In software update 2026.14, released as part of the Spring Update, European Tesla owners are now seeing flat-fronted, cab-over European-style semi-trucks rendered accurately on their center displays.
The change, first spotted by Not a Tesla App, adds a second 3D model alongside the traditional North American long-nose semi-trucks that have been standard until now. Vehicles can detect and display both styles depending on what’s in front of them, and the feature requires no FSD subscription—every Tesla owner in Europe sees it immediately.
The European semi-truck visualization was actually added to the vehicle software back in October alongside roughly fifteen new visual assets.
Tesla held it in reserve, activating it only once fleet data confirmed the AI could recognize these trucks with high confidence. This mirrors recent rollouts for horses and golf carts, where Tesla similarly waited for reliable detection before enabling the graphics. The result is a more realistic on-screen representation tailored to local roads, where cab-over designs dominate heavy transport.
The significance of this update extends far beyond a simple graphics tweak, which is really what people need to be paying attention to. These small, incremental steps forward continue to show Tesla’s intent for global expansion.
For the first time, Tesla is explicitly factoring international vehicle designs into its visualization engine, signaling a deliberate push to make FSD feel native in international markets.
In Europe, where cab-over semis are commonplace, seeing an accurate rendering builds immediate driver trust—the critical bridge between the car’s AI perception and the human behind the wheel. Accurate visualizations reinforce that the system truly understands its surroundings, reducing range anxiety and skepticism that have slowed autonomous adoption abroad.
Regulators in the EU have repeatedly emphasized human-AI transparency; by customizing visuals to match local reality, Tesla strengthens its case for broader FSD approvals and smoother regulatory reviews.
This move also highlights Tesla’s data-driven engineering philosophy. Rather than rushing generic models worldwide, the company is leveraging its global fleet to learn regional nuances before flipping the switch.
It accelerates FSD’s international expansion while improving safety—misidentified vehicles could erode confidence or, in edge cases, affect decision-making. For a company aiming to deploy robotaxis and unsupervised FSD globally, tailoring visualizations to European, Asian, or other markets is no longer optional; it’s foundational.
Early European owners report the change feels more intuitive, making the car’s “mind” easier to read in daily traffic.
As Tesla continues enabling the remaining visual assets added last year, the pattern is clear: localization is now baked into the FSD roadmap. What began as a small graphics update in Europe could soon appear in other regions, turning the visualization display into a truly worldwide language of autonomy.
With this step, Tesla isn’t just showing trucks differently—it’s proving it’s serious about making FSD work everywhere, one culturally accurate pixel at a time.
Tesla Roadster gets an update, but not the one fans were looking for
Tesla gets a massive order for the Semi: 370 units and $100M
