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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Elon Musk
Tesla China posts strong February wholesale growth at Gigafactory Shanghai
The update was shared by Tesla observers on social media platform X, citing monthly China Passenger Car Association (CPCA) data.
Tesla China sold 58,599 vehicles wholesale in February, reflecting strong year-over-year growth. The figure includes both domestic deliveries in China and vehicles exported to international markets.
The update was shared by Tesla observers on social media platform X, citing monthly China Passenger Car Association (CPCA) data.
Tesla’s February wholesale result represents a 91% increase year over year, compared with 30,688 vehicles in February 2025. Month over month, the result was down 15.2% from January, when Tesla China recorded 69,129 wholesale units.
The February total reflects combined sales of the Model 3 and Model Y produced at Gigafactory Shanghai. The facility produces the two vehicles for both domestic sales and exports.
Gigafactory Shanghai continues to serve as Tesla’s primary vehicle export hub, supplying vehicles to markets across Asia and Europe. Data compiled by Tesla watchers shows that 18,485 vehicles were sold domestically in China in January 2026, while exports accounted for 50,644 units during the same period.
Tesla has also been extending financing programs in China as it pushes to strengthen domestic demand. The company recently extended its seven-year ultra-low-interest and five-year interest-free financing programs through March 31, marking the second extension of the promotion this year.
The financing initiative was first introduced on January 6 as a strategy aimed at offsetting higher ownership costs ahead of China’s planned 5% NEV purchase tax in 2026. The promotion was originally scheduled to expire at the end of January before being extended to February and then again through the end of the first quarter.
Tesla’s efforts come amid growing competition in China’s EV market. According to data compiled by CNEV Post, Tesla’s 2025 retail sales in China reached 625,698 vehicles, representing a 4.78% year-over-year decline. Part of that decline was linked to the Model Y changeover to its updated variant in early 2025, which temporarily reduced deliveries during the transition period.
News
Tesla Model Y L spotted on transport trucks in Australia
One of the sightings was reported along Victoria Parade in Melbourne, and it showed multiple Model Y L vehicles on a transport carrier.
Tesla’s upcoming Model Y L has been spotted on transport trucks in Australia. Sightings of the six-seat extended wheelbase Model Y variant have been reported on social media platform X by members of the Australian Tesla community.
One of the sightings was reported along Victoria Parade in Melbourne, and it showed multiple Model Y L vehicles on a transport carrier.
The sighting follows earlier observations by Tesla enthusiasts in Sydney, where a covered vehicle believed to be a Model Y L was spotted at a Supercharger.
The Sydney sighting drew attention after observers noted that the vehicle’s tare weight appeared to match the ADR approval listing for the Model Y L, suggesting it could indeed be the extended wheelbase variant of the electric SUV.
Tesla has previously confirmed that the Model Y L will launch in Australia and New Zealand in 2026. The confirmation was reported by techAU following a media release from Tesla Australia and New Zealand.
The Model Y L expands the existing Model Y lineup with seating for six passengers. The vehicle features a longer body compared with the standard Model Y in order to accommodate a spacious second and third row.
Tesla has opted for a 2-2-2 seating configuration instead of a traditional seven-seat layout for the Model Y L. The design includes two individual seats in the middle row to provide easier access to the third row and additional passenger space.
Tesla Australia and New Zealand has also stated that the Model Y L will be covered under the company’s updated warranty structure beginning in 2026.
Tesla has not yet announced pricing or official range figures for the Model Y L in Australia.
Elon Musk
Elon Musk shares timeframe for X Money early public access rollout
X Money is expected to enable financial transactions within the app, expanding the platform’s capabilities beyond social media features.
Elon Musk has stated that X Money, the digital payments system being developed for social media platform X, is expected to enter early public access next month.
The update was shared by Musk in a post on X. “𝕏 Money early public access will launch next month,” Musk wrote in his post.
As noted in a Reuters report, X Money is being developed as a digital payment service that’s directly integrated into the X platform.
The system is expected to enable financial transactions within the app, expanding the platform’s capabilities beyond social media features.
Musk has previously discussed plans to introduce payments and financial services as part of X’s broader development.
Since acquiring the platform in 2022, Musk has discussed expanding X to include a range of services such as messaging, media, and financial tools.
Elon Musk has shared his goal of transforming X into an “everything app.” During a previous podcast interview with members of the Tesla community, Musk mused about turning X into something similar to China’s WeChat, which allows users to shop, pay, communicate, and perform a variety of other tasks.
“In China, you do everything in WeChat… it’s kickass… Outside of China, there’s nothing like it, people live on one app. My idea would be like how about if we just copy WeChat,” Musk joked at the time.
To prepare for the rollout of X Money, X has partnered with payment company Visa to support the development of payment services for the platform’s users. The move could allow X to tap into the growing demand for digital and in-app financial transactions as the company builds additional services around its existing user base.
Tesla China posts strong February wholesale growth at Gigafactory Shanghai
Tesla Model Y L spotted on transport trucks in Australia
