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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Tesla will increase its Full Self-Driving subscription price, meaning it will eventually be more than the current $99 per month price tag it has right now.
Already stating that the ability to purchase the suite outright will be removed, Tesla CEO Elon Musk said earlier this week that the Full Self-Driving subscription price would increase when its capabilities improve:
“I should also mention that the $99/month for supervised FSD will rise as FSD’s capabilities improve. The massive value jump is when you can be on your phone or sleeping for the entire ride (unsupervised FSD).”
This was an expected change, especially as Tesla has been hinting for some time that it is approaching a feature-complete version of Full Self-Driving that will no longer require driver supervision. However, with the increase, some are concerned that they may be priced out.
$99 per month is already a tough ask for some. While Full Self-Driving is definitely worth it just due to the capabilities, not every driver is ready to add potentially 50 percent to their car payment each month to have it.
While Tesla has not revealed any target price for FSD, it does seem that it will go up to at least $150.
I should also mention that the $99/month for supervised FSD will rise as FSD’s capabilities improve.
The massive value jump is when you can be on your phone or sleeping for the entire ride (unsupervised FSD). https://t.co/YDKhXN3aaG
— Elon Musk (@elonmusk) January 23, 2026
Additionally, the ability to purchase the suite outright is also being eliminated on February 14, which gives owners another reason to be slightly concerned about whether they will be able to afford to continue paying for Full Self-Driving in any capacity.
Some owners have requested a tiered program, which would allow people to pay for the capabilities they want at a discounted price.
Unsupervised FSD would be the most expensive, and although the company started removing Autopilot from some vehicles, it seems a Supervised FSD suite would still attract people to pay between $49 and $99 per month, as it is very useful.
Tesla will likely release pricing for the Unsupervised suite when it is available, but price increases could still come to the Supervised version as things improve.
This is not the first time Musk has hinted that the price would change with capability improvements, either. He’s been saying it for some time. In 2020, he even said the value of FSD would “probably be somewhere in excess of $100,000.”
The FSD price will continue to rise as the software gets closer to full self-driving capability with regulatory approval. It that point, the value of FSD is probably somewhere in excess of $100,000.
— Elon Musk (@elonmusk) May 18, 2020
Tesla has chosen to axe the ability to purchase Full Self-Driving outright from a select group of cars just days after CEO Elon Musk announced the company had plans to eliminate that option in February.
The company is making a clear-cut stand that it will fully transition away from the ability to purchase the Full Self-Driving suite outright, a move that has brought differing opinions throughout the Tesla community.
Earlier this week, the company also announced that it will no longer allow buyers to purchase Full Self-Driving outright when ordering a pre-owned vehicle from inventory. Instead, that will be available for $99 per month, the same price that it costs for everyone else.
The ability to buy the suite for $8,000 for a one-time fee at the time of order has been removed:
NEWS: Tesla no longer allows buyers to purchase FSD outright in the U.S. when ordering a pre-owned vehicle directly from inventory. Tesla now gives you the option to either subscribe for $99/month, or purchase FSD outright after taking delivery (available until February 14th). pic.twitter.com/1xZ0BVG4JB
— Sawyer Merritt (@SawyerMerritt) January 23, 2026
This is a major move because it is the first time Tesla is eliminating the ability to purchase FSD outright for one flat fee to any of its vehicles, at least at the time of purchase.
It is trying to phase out the outright purchase option as much as it can, preparing people for the subscription-based service it will exclusively offer starting on February 14.
In less than a month, it won’t be available on any vehicle, which has truly driven some serious conversation from Tesla owners throughout the community.
There’s a conflict, because many believe that they will now lose the ability to buy FSD and not pay for it monthly, which is an attractive offer. However, others believe, despite paying $8,000 for FSD, that they will have to pay more money on top of that cost to get the unsupervised suite.
Additionally, CEO Elon Musk said that the FSD suite’s subscription price would increase over time as capabilities increase, which is understandable, but is also quite a conflict for those who spent thousands to have what was once promised to them, and now they may have to pay even more money.
News
Tesla Robotaxi has a highly-requested hardware feature not available on typical Model Ys
These camera washers are crucial for keeping the operation going, as they are the sole way Teslas operate autonomously. The cameras act as eyes for the car to drive, recognize speed limit and traffic signs, and travel safely.
Tesla Robotaxi has a highly-requested hardware feature that is not available on typical Model Ys that people like you and me bring home after we buy them. The feature is something that many have been wanting for years, especially after the company adopted a vision-only approach to self-driving.
After Tesla launched driverless Robotaxi rides to the public earlier this week in Austin, people have been traveling to the Lone Star State in an effort to hopefully snag a ride from one of the few vehicles in the fleet that are now no longer required to have Safety Monitors present.
BREAKING: Tesla launches public Robotaxi rides in Austin with no Safety Monitor
Although only a few of those completely driverless rides are available, there have been some new things seen on these cars that are additions from regular Model Ys, including the presence of one new feature: camera washers.
With the Model Y, there has been a front camera washer, but the other exterior “eyes” have been void of any solution for this. For now, owners are required to clean them manually.
In Austin, Tesla is doing things differently. It is now utilizing camera washers on the side repeater and rear bumper cameras, which will keep the cameras clean and keep operation as smooth and as uninterrupted as possible:
🚨 Tesla looks to have installed Camera Washers on the side repeater cameras on Robotaxis in Austin
pic.twitter.com/xemRtDtlRR— TESLARATI (@Teslarati) January 23, 2026
Rear Camera Washer on Tesla Robotaxi pic.twitter.com/P9hgGStHmV
— TESLARATI (@Teslarati) January 24, 2026
These camera washers are crucial for keeping the operation going, as they are the sole way Teslas operate autonomously. The cameras act as eyes for the car to drive, recognize speed limit and traffic signs, and travel safely.
This is the first time we are seeing them, so it seems as if Safety Monitors might have been responsible for keeping the lenses clean and unobstructed previously.
However, as Tesla transitions to a fully autonomous self-driving suite and Robotaxi expands to more vehicles in the Robotaxi fleet, it needed to find a way to clean the cameras without any manual intervention, at least for a short period, until they can return for interior and exterior washing.
Tesla to increase Full Self-Driving subscription price: here’s when
Tesla starts removing outright Full Self-Driving purchase option at time of order
