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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 entered two new markets this week by advancing its presence in Latvia (Europe) and officially launching operations in Uruguay (South America), marking a rapid dual-continent expansion.
These moves underscore the company’s strategy to tap into emerging EV markets with supportive policies, renewable energy grids, and growing demand for sustainable transport.
Latvia: Strengthening the Baltic Footprint
In Latvia, Tesla has built on its earlier registration of Tesla Latvia SIA in late 2025 with recent steps toward full operations, including job postings for a service center and representation in Riga. This aligns with broader Baltic expansion following Lithuania’s model of pop-up stores and service centers.
Coming to Latvia https://t.co/XNkQQJ2O6a pic.twitter.com/yS9kpcNky1
— Tesla Europe, Middle East & Africa (@teslaeurope) July 17, 2026
EV penetration in Latvia stands at around 7 percent for BEVs in new passenger car registrations. 2025 data showed 1,602 BEVs out of about 22,500 total, or 7.1 percent, with combined plug-ins nearing 19 percent. Growth has been steady but below the European average, supported by government subsidies and infrastructure development. Tesla models like the Model 3 lead local EV registrations.
Vehicles for the Latvian market will likely be sourced from Gigafactory Berlin or Gigafactory Shanghai. Charging infrastructure is robust for the region as well, with over 400- 2,000 public points, with Tesla Superchargers in Riga, Jūrmala, and along Via Baltica routes offering up to 250 kW.
Uruguay: Third South American Country
Tesla teased its Uruguay arrival with “Estamos llegando,” or, “We are arriving,” on social media, followed by an official presentation scheduled for mid-July.
Hola Uruguay 🇺🇾
Nuestros Model 3 y Model Y están cada vez mas cerca! pic.twitter.com/FR41fsA7um
— Tesla Latinoamérica (@Tesla_LatAm) June 30, 2026
The company established Tesla Uruguay SAS, homologated Model 3 and Model Y (three versions each), and appointed local leadership. This makes Uruguay Tesla’s third official South American market after Chile and Colombia.
Uruguay boasts one of Latin America’s highest EV penetrations, with battery-electric vehicles exceeding 20 percent market share recently, driven by tax incentives, high fuel prices, and a nearly 95-100 percent renewable electricity grid. Hundreds of Teslas already operate via grey imports, but official sales bring warranties, service, and support.
Vehicles will be imported from Gigafactory Shanghai, enabling competitive pricing for Model 3 and Model Y. Charging plans include Supercharger development alongside existing infrastructure, leveraging the country’s green energy advantage for affordable operation.
Tesla Superchargers follow Model 3 and Model Y to South American country
Tesla’s Dual Continent Expansion
Tesla’s simultaneous push into Latvia and Uruguay demonstrates efficient scaling: prioritizing service and infrastructure first, then direct sales in high-potential niches. In Europe, it fills Baltic gaps; in Latin America, it counters Chinese dominance while leveraging renewables.
This dual move signals Tesla’s ambition to accelerate global EV adoption amid varying regional paces. By addressing local needs, like subsidies in Latvia or incentives and green grids in Uruguay, Tesla not only boosts volumes but advances its mission of sustainable energy.
For investors and consumers, it highlights resilience and opportunity in diverse markets, potentially paving the way for further growth in underserved regions. With strong fundamentals in both, these entries could yield long-term gains as EV transitions mature worldwide.
SpaceX has announced a new target date for the thirteenth test flight of Starship: Monday, July 20, with the launch window opening at 6:45 p.m ET/5:45 p.m. CT.
This is the first rescheduling attempt of Starship’s 13th test flight. It was set to launch last night, but SpaceX scrubbed the launch attempt.
🚨 SpaceX is now looking at Monday, July 20th at 6:45 p.m ET/5:45 p.m. CT for the 13th test flight of Starship pic.twitter.com/7s8aMJV5Ge
— TESLARATI (@Teslarati) July 17, 2026
CEO Elon Musk revealed that some of the engines on Starship did not start, which automatically triggers a launch abort. Two of the Raptor engines will be removed and replaced.
To be confident of a good flight, 2 Raptors will be removed & replaced. Most probable launch timing is early next week.
— Elon Musk (@elonmusk) July 17, 2026
SpaceX officially announced the new launch window this morning.
Starship’s 13th test launch comes with a few new objectives, but SpaceX does not plan to attempt a catch of the booster, which it has done several times in the past.
For Starship’s Upper Stage, there are some adjustments to ensure engine reusability that will be assessed during the ascent, and 20 operational Starlink V3 satellites are also set to make their way into space. SpaceX also plans to attempt an in-space relight of a single Raptor engine, which is a critical demonstration for future orbital deorbit, refueling, and deep space maneuvers.
Ultimately, it will splash down in the Indian Ocean.
The continuous tests help SpaceX advance the Starship program toward eventual full reusability, operational Starlink V3 deployment, and future missions, which include NASA’s Artemis program.
Elon Musk
SpaceX Starship Flight 13 aborted at Zero and Musk just told us what broke
Four Raptor engines failed to ignite at T-zero, forcing SpaceX to scrub Starship Flight 13 Thursday.
SpaceX scrubbed the Starship Flight 13 launch attempt Thursday evening at the last possible moment, after four of the Super Heavy booster’s 33 Raptor 3 engines failed to ignite during the startup sequence. The 90-minute window had opened at 6:45 p.m. EDT from Starbase in Boca Chica, Texas, and the countdown had proceeded without issue all day, with more than 11.5 million pounds of liquid methane and liquid oxygen being fully loaded into the rocket before the automated abort triggered. SpaceX’s launch directors posted on X, “Standing down from today’s flight test attempt,” and shut down the livestream shortly after.
Musk confirmed the root cause within hours. “Some of the engines didn’t start, triggering an automatic launch abort,” he wrote on X. “To be confident of a good flight, 2 Raptors will be removed and replaced. Most probable launch timing is early next week.” SpaceX engineers began draining propellant tanks immediately and Booster 20 was rolled back to its hangar for inspection.
The timing adds a layer of significance that did not exist during any of the previous 12 Starship flights. This is the first time SpaceX has attempted to launch Starship since the company made its stock market debut in June, listing under ticker SPCX at $135 per share. Public investors are now watching every Starship outcome in real time, and a last-second abort carries more visibility than it would have six months ago.
Flight 13 was designed to be one of the most consequential tests in the program’s history. It was set to carry 20 Starlink V3 satellites, the first operational payload Starship has ever attempted to deploy. Six of those satellites carried external cameras to photograph Starship’s heat shield from the outside during flight, which would act as a self-inspection approach SpaceX has never attempted before. The mission also needed to complete a Raptor engine relight in space, a step SpaceX skipped on Flight 12 in May after losing an engine during ascent. That Flight 12 booster also flipped 90 degrees off course during its boostback burn when five engines failed to reignite.
SpaceX has not announced an official next launch date. Musk’s “early next week” window points to July 21 or 22 at the earliest, pending the engine swap and a return to the pad.
Tesla enters two new markets on two different continents in one week
SpaceX announces new Starship 13 test flight target date
