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.
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The research was funded by the National Science Foundation and the Department of Defense.
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News
SpaceX just launched a secret payload from California
SpaceX launched a classified Space Force mission from Vandenberg, revealing almost nothing about its payload.
SpaceX launched a classified Falcon 9 mission for the U.S. Space Force from Vandenberg Space Force Base on Saturday night, and the government released almost nothing about what was on board. The mission, designated USSF-366, lifted off from Space Launch Complex 4E with a window that opened at 9:52 p.m. ET and ran into the early hours of Sunday, according to SpaceX’s own mission page, which described the payload only as classified. SpaceX confirmed the launch on its X account and pointed viewers to a livestream that began roughly ten minutes before liftoff.
Watch Falcon 9 launch the USSF-366 mission from pad 4E in California https://t.co/FFEzeYOds1
— SpaceX (@SpaceX) August 16, 2026
The lack of detail did not stop analysts from filling in the blanks. Independent tracking of the rocket’s stage drop zones matched the pattern SpaceX has used on previous Starlink Group 15 missions, according to reporting from Outer Space Today, which pointed to Starshield as the likely payload rather than a one off government satellite. Starshield is SpaceX’s national security product, a version of the Starlink satellite bus built to Pentagon specifications for earth observation, communications and hosted payloads. Unlike consumer Starlink, government agencies do not have to disclose what Starshield satellites are actually doing once they reach orbit.
USSF-366 is the latest entry in a steady flow of classified and semi classified work between SpaceX and the Space Force. The company picked up a $178.5 million task order in April to launch missile tracking satellites for the Space Development Agency, as Teslarati reported at the time, and followed that in July with a $1.6 billion award covering 18 more Falcon 9 missions from Vandenberg through the end of 2027, also detailed by Teslarati. Add those contracts up and SpaceX’s Pentagon business for 2026 alone tops $8 billion.
SpaceX scores another massive Pentagon deal to support military satellites
The Falcon 9 that flew Saturday landed back near the launch site, producing the sonic booms that have become routine for residents near Vandenberg. What is less routine is how little the public will likely ever learn about what the rocket carried. SpaceX and the Space Force have not confirmed the Starshield connection, and government satellite programs built on commercial buses rarely get identified beyond a mission number and a general orbit. For a company that live streams almost everything else it does, from Starship test flights to Optimus robot demos, USSF-366 is a reminder that some of SpaceX’s busiest work now happens entirely out of public view.
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On Friday, Tesla launched the Outlet Adapter that enabled Vehicle-to-Load (V2L) energy transfer, meaning owners could essentially utilize their cars as a power source for things like laptops, electric grills, or string lights.
However, even owners of some of the newest builds of the Model Y are finding out that their cars are not compatible with the new $80 accessory, stirring up a new complaint among members of the community.
Tesla launches V2L Outlet Adapter for Premium Model Y in the U.S.
Upon the release of the Outlet Adapter on Friday, I signed into my Tesla account to order the accessory. However, I was met with the dreaded “This product is not compatible with your 2026 Model Y” message at the bottom of the screen.
Some said their accounts also displayed the same message, but they ordered anyway. However, they might be surprised to find that this is no mistake; some of the newest Model Ys do not have the appropriate Power Conversion System (PCS). Mine, which was ordered on this day last year and delivered on August 31, has the old 48A, single-phase PCS.
Vehicles with the new, two-piece PCS are able to utilize V2L features on their cars:
🚨 Looks like you can hit the Parts Catalog and enter your VIN and check to see if your Model Y will be able to use the adapter for V2L.https://t.co/QA9zRk7n2k
h/t to @SawyerMerritt for finding this out.
-I am sad but this isn’t a huge loss. https://t.co/AYpI12QVV9 pic.twitter.com/LRFSrtRywo
— TESLARATI (@Teslarati) August 16, 2026
Obviously, it’s disappointing. Many owners have taken delivery this year and still can not utilize the Outlet Adapter because their cars feature the old PCS:
Took delivery in February of 2026. I have the older one, so not going to work for me pic.twitter.com/RcOVq8gvvT
— Russell (@QuietTesla) August 16, 2026
It looks like if you have one of these older PCS units, you can upgrade, but the parts alone are $1,750, and that’s before Tesla adds labor for installing. It is honestly more logical to get some kind of portable power supply or power station at that point.
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It is great that Tesla has enabled V2L for Model Y vehicles, but it is also unfortunate that vehicles that are less than one year old are not able to take advantage of this awesome new feature.
With that being said, it truly is a first-world problem; can you really complain when Full Self-Driving is available, maintenance is incredibly inexpensive, and the car has been so good through a year of ownership?
Tesla has launched a new Vehicle-to-Load (V2L) Outlet Adapter for Premium Model Y vehicles in the United States, meaning you can now power devices like laptops or light strings with your vehicle’s battery.
It appears the capability will be available for any Model Y Premium trim, including those that were purchased prior to the Adapter being launched. It will also only impact Juniper Model Y vehicles, so the first-gen owners will unfortunately not have access to this capability.
If your Model Y was purchased before Tesla renamed the trim levels to “Premium” and “Standard,” it does not seem to be compatible. My Model Y is technically a Premium build, as it is the Long Range All-Wheel-Drive. However, Tesla says it is not compatible with my vehicle.
🚨 Tesla has launched the Outlet Adapter for Model Y Premium in the U.S., enabling V2L capability for all Premium trims (that’s what it appears to be as it is available for purchase with all Premium trims)
It’s available for $80. 2.4kW max power and rated for 120v, 20A pic.twitter.com/lDxlVIk5s8
— TESLARATI (@Teslarati) August 14, 2026
For $80, you can now utilize your car as a portable charger for small appliances or devices. This is perfect for things like tailgates, concerts, or camping, as you can now plug in devices that you might use. Those string lights for camping? That laptop for the other games that are on at the tailgate?
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They’ll both utilize energy from your Tesla’s battery to be powered. This is the first time Tesla has expanded the capability to vehicles outside of the Model Y Performance and Cybertruck. However, this feature has been highly requested by owners for an extended period of time.
Tesla launched the Outlet Adapter in China last year:
Tesla China rolls out Model Y L V2L adapter, and it’s free for early owners
You will need the Mobile Connector to operate the Outlet Adapter: the Outlet Adapter will plug into the main housing of the Mobile Connector, where the appropriate adapter to charge your vehicle will plug in.
It is rated for 120 volts and 20 amps, and has a max power rating of 2.4kW.
You can buy it here from Tesla for $80.
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SpaceX just launched a secret payload from California
Tesla V2L adapter for Model Y stirs up a new complaint among owners
