Lithium News

Researchers at Yokohama National University have developed a stretchy, high-precision measurement wearable device that combines soft polymer materials and rigid electronic elements. This device can accurately measure inertial data even if it extends up to 2.5 times its length.

The combination of this stretchable high-precision device and machine learning achieved multiple types of motion recognition with a high accuracy rate. The potential applications of this technology have led to the realization of systems that integrate various soft and rigid electronics with information technology.

Stretchable, wearable devices that can sense physical and bioelectrical information quickly and accurately are increasingly being used for things like health monitoring and motion measurement. However, making a device that is stretchy enough to be comfortable and rigid enough to accurately sense data is difficult.

Machine learning can help make these devices more powerful, but in order to integrate the technology, stretchable hybrid wearables that combine comfort and stable data processing will need to be developed.

A paper published in Device on August 7 outlines how rigid integrated circuits layered on a flexible substrate can be used to improve wearable performance.

“Stretchable devices combining high-performance sensor integrated circuits based on solid-state electronics have been developed, but they lack the stretchability to accommodate large deformations of more than two times elongation. These factors have limited the development of integrated systems for stretchable devices and machine learning,” said Hiroki Ota, associate professor in the Faculty of Engineering at Yokohama National University.

In fact, Ota explained, there are no devices currently available on the market that can measure with both high accuracy and high repeatability among stretchable devices (or devices that have high deformability).

In this study, researchers focused on developing motion capture wearables with integrated machine learning. The devices were very deformable, meaning they were flexible and could contour to the body.

Structures called heterogeneous-rigidity protective structures were developed to provide the extra stability to the flexible wearables. These structures protected the electrical wiring and had three layers: a hard layer, an intermediate layer, and a soft layer.

The soft layer ensured the device remained stretchy and the harder layers maintained the integrity of the sensors in the device. Liquid metal paste was also used throughout the device, including to develop the wiring, to ensure the device remained flexible.

“The fusion of stretchable materials and solid-state electronics-based rigid elements realizes novel devices that combine elasticity with high computing and measurement capabilities. These devices promote integration with machine learning systems, where data reproducibility is critical,” said Ota.

To test the power of the wearable device, researchers performed three tasks: self-shape estimation of knots, recognizing writing in the air, and sign-language recognition. Researchers also tested how well the device continued to work as it was stretched.

When compared to previous iterations of wearable devices that only have a circuit board, the newly developed device with the heterogeneous-rigidity protective structure was better at handling elongation and stretching. The device with only the circuit board and soft layer showed strain at 30% elongation and it broke at 100% elongation.

In comparison, at 100% elongation the device with the heterogeneous-rigidity protective structure did not show any signs of damaging strain and it continued to work even if stretched to 150%.

The devices were also tested to see how well they performed at certain assigned tasks, including recognizing the letters spelled during finger spelling and sign-language recognition.

Currently, wearable devices used to track finger spelling have difficulty with parallel movements without finger bending. The newly developed heterogeneous-rigidity device was able to accurately classify between 91% and 98% of the letters spelled, depending on the processing model used to analyze the data, but additional research is needed to understand differences in the training models.

Researchers also posited that the technology could go beyond finger spelling and recognize American Sign Language, a highly sought-after technology. The challenges for developing this technology, however, go beyond the limitations of stretchable, wearable devices and additional development is needed.

Looking ahead, researchers plan to develop more devices with this new technology.

“Ultimately, we aim to realize stretchable hybrid electronics that integrate solid-state and stretchable electronics by utilizing the electronic properties of both rigid devices and elastic materials, and by integrating them with information processing technology,” said Ota.

Matt Riggs’ family has been farming in Urbana since 1874. But, his parents had to work second jobs to cushion themselves from the volatile corn and soybean markets that dominate Illinois’ agricultural sector.

In the past few years, Riggs has realized the land his family has worked for 150 years is also ideal for solar panels. It’s flat, well-drained and gets lots of sunlight.

As Illinois strives to convert 40% of its energy consumption to renewables by 2030 and 100% by 2050, solar installations are expected to increase by 1,700% over the next five years, according to the Solar Energy Industries Association.

Across the country, approximately 83% of new solar projects developed by 2040 will be installed on farm and ranch land, according to a 2022 American Farmland Trust analysis.

But, broad, low-lying solar arrays are not inherently compatible with farming. They typically take land out of agricultural production. This doesn’t have to be the case, however. An emerging field called agrivoltaics suggests shorter, shade-tolerant crops may grow well in the small spaces between panels.

After installing solar panels at his brewery and seeing how reliable they were, Riggs wondered if he could use them to hedge his farm’s balance sheet.

“The sun is going to come up on average a certain amount of time so you can build a really stable, predictable financial model, which I looked at having grown up on a farm and was like ‘Wow, that’s awesome,'” said Riggs.

Some Google searches led him to agrivoltaics.

While there are very few agrivoltaic projects in Illinois, early research and small projects show synergies between solar energy and agriculture. The co-location of solar panels and agriculture could keep farmers in business, improve ecosystem health, feed the country and provide clean energy.

The vast majority of our portable electronic gadgets, and the new wave of electric transportation, are powered by lithium batteries. Texas-based startup Group1 has developed a more sustainable alternative, and has now launched the world’s first 18650 potassium-ion battery.

Group1 was co-founded in 2021 by battery tech veterans, including Leigang Xue who currently serves as Chief Product Officer but previously worked in the lab of 2019 Nobel Laureate and battery pioneer Dr. John Goodenough at University of Texas at Austin – who co-invented the Li-ion battery.

It was in this lab that Dr. Xue invented the company’s Potassium Prussian White (KBW) cathode material – which is reported to be the key development that enables production of the “safer, quickly charging, more efficient and sustainable” potassium-ion battery (KIB).

To make a KIB cell, KBW is paired with a commercial-grade graphite anode, along with readily available electrolyte formulations and separators – with the company also highlighting the distinct lack of critical minerals like lithium, cobalt, nickel and copper in the new batteries.

“As our transition away from fossil fuels accelerates, the demand for lithium-ion batteries is spiking quickly, and our lithium supplies will soon be incapable of meeting that demand,” said CEO Alexander Gira as the company came out of stealth in 2022. “Group1 and potassium-ion batteries can provide a viable alternative to bridge this supply gap.”

Group1 notes that potassium is more than a thousand times more abundant than lithium, and its KBW cathode is produced using low-temperature sustainable processes.

Development began small with a coin-cell battery, then progressed to a pouch-cell format and now the world’s first 18650 KIB has been unveiled. This format should mean relatively easy deployment to electric vehicle manufacturers, as well as potential use in power banks and portable gadgetry, for the promise of “the best combination of performance, safety, and cost when compared to LiFePO4 (LFP)-based Li-ion batteries and sodium-ion batteries.”

The new cells operate at 3.7 volts and are reported to have exceeded performance expectations, demonstrating “a practical path to achieve a gravimetric energy density of 160-180 Wh/kg.” Though this is up there with typical LFP packs currently in the wild, it still lags behind the next-gen CATL Shenxing Plus batteries – which top out at 205 Wh/kg. In a straight performance shootout, it’s even farther behind the lithium batteries in the lab as well as 4680 cells found in Tesla’s electric vehicles, for example.

Group1 has sent out samples to “key Tier 1 OEMs” and battery cell manufacturers, aiming for “widespread adoption of this transformative technology” in the very near future.

Lithium-ion batteries have a lot of advantages. They charge quickly, have a high energy density, and can be repeatedly charged and discharged.

They do have one significant shortcoming, however: they’re prone to short-circuiting. This occurs when a connection forms between the two electrodes inside the cell. A short circuit can result in a sudden loss of voltage or the rapid discharge of high current, both causing the battery to fail. In extreme cases, a short circuit can cause a cell to overheat, start on fire, or even explode.

A leading cause of short circuits are rough, tree-like crystal structures called dendrites that can form on the surface of one of the electrodes. When dendrites grow all the way across the cell and make contact with the other electrode, a short circuit can occur.

Using the Canadian Light Source (CLS) at the University of Saskatchewan (USask), researchers from the University of Alberta (UAlberta) have come up with a promising approach to prevent formation of dendrites in solid-state lithium-ion batteries. They found that adding a tin-rich layer between the electrode and the electrolyte helps spread the lithium around when it’s being deposited on the battery, creating a smooth surface that suppresses the formation of dendrites.

The results are published in the journal ACS Applied Materials and Interfaces. The team also found that the cell modified with the tin-rich structure can operate at a much higher current and withstand many more charging-discharging cycles than a regular cell.

Researcher Lingzi Sang, an assistant professor in UAlberta’s Faculty of Science (Chemistry), says the CLS played a key role in the research.

“The HXMA beamline enabled us to see at a material’s structural level what was happening on the surface of the lithium in an operating battery,” says Sang. “As a chemist, what I find the most intriguing is we were able to access the exact tin structure that we introduced to the interface which can suppress dendrites and fix this short-circuiting problem.”

In a related paper the team published earlier this year, they showed that adding a protective layer of tin also suppressed the formation of dendrites in liquid-electrolyte-based lithium-ion batteries.

This novel approach holds considerable potential for industrial applications, according to Sand. “Our next step is to try to find a sustainable, cost-effective approach to applying the protective layer in battery production,” adds Sang.

You may think it’s just an old wives’ tale, but it’s actually true: Temperature impacts the life of your car battery.

Extreme temperatures — something we know a bit about here in the South — are particularly cruel to our car batteries. While an average car battery can live about 5 years in more northern U.S. regions, battery life can be around 3.5 years or shorter for those in the warmer, southernmost regions.

“Most drivers know that the cold is rough on car batteries, but many don’t realize that heat is actually the number one cause of battery failure and reduced battery life,” said Tiffany Wright, public affairs director for AAA -The Auto Club Group in the Carolinas.

Hot air temperatures drive up the temperature under the hood — especially when the vehicle is in direct sunlight. In the summer, battery fluid can evaporate much faster, leading to corrosion on terminals and connections, Wright said.

“Summer heat accelerates the rate of fluid loss, resulting in oxidation of battery components, which can leave you stranded without warning,” Wright said.

The number of drivers who call for assistance increases significantly when temperatures are above 90 degrees for a few days straight, according to Wright. The most calls for AAA assistance in the summer come from drivers with dead batteries and flat tires, she said.

AAA reportedly responded to 1.93 million service calls related to batteries during the summer of 2023.

What should you do if you live in a warmer climate? How can you protect your car battery?

Experts suggest parking your vehicle in the shade or a garage whenever you can. Drivers should also avoid using their battery when the engine isn’t on, which can drain the battery.

It’s a good idea to clean the battery posts often enough to prevent the buildup of dirt, grime and corrosion.

“Heat and vibration are a battery’s two worst enemies leading to internal breakdown and eventual failure. While drivers can’t do much about the heat, they can make sure their battery is securely mounted in place to minimize vibration,” AAA said. “Check the car battery to be sure cable connections are clean and tight, and the hold down hardware is secure. Dirty, loose connections limit the flow of current and are a common cause of battery issues.”

Experts also suggest driving the vehicle regularly — for at least 20 minutes per trip — to replenish the battery.

How often should you check in on your car battery?
Experts encourage drivers living in warmer climates to have their car battery load tested every year once the battery reaches 2 years old. Load tests help determine the battery’s ability to hold voltage while being used.

Load tests typically need to be carried out by professionals with the proper equipment. These test results can help identify how much longer you can trust your battery to operate properly.

You can also check in on the voltage of your battery, but it’s not necessarily a good indicator of how much life is actually left in the battery.

AAA says its members can request a free battery check from a service professional.

Most experts agree that it’s better to be proactive rather than reactive when it comes to car battery health. Car batteries can give out at any moment and without warning. Checking in on the battery can help you decide when it’s time to buy a new one.

About 12,000 Chinese households can now be powered by salt.

In truth, the “world’s largest” sodium-ion battery system in Qianjiang is proof that the unique power pack chemistry can store a hoard of renewable energy, reliably putting it on the grid, according to PV Magazine and Interesting Engineering.

The system was put online in June by state-owned power provider Datang Group, turning heads across the energy sector.

“The growing storage capacities of these units show that the sodium-ion batteries are no longer limited to the laboratories and are making their presence felt in the market,” IE’s Ameya Paleja wrote.

The power packs are the first part of a storage station being completed in phases. It includes 42 energy storage containers provided by HiNa Battery Technology. Throwing the switch on the project was a score for the development team after a long series of “difficulties,” all per PV’s report.

Sodium-ion batteries have some impressive advantages over common lithium-ion packs, used in most electric vehicles and other large storage units, like Tesla’s Megapacks.

When mass produced, the salt-based batteries could be much cheaper to make than alternatives on the market because sodium is abundant and less costly to harvest than lithium. Aluminum can be used as an anode instead of more expensive copper, reducing expenses even more, all per PV.

The article also noted challenges that need to be overcome to bring the science to fruition, something the Chinese experts have apparently achieved with the Datang project.

“Before sodium ion batteries can challenge existing lead acid and lithium iron phosphate batteries, industry players will need to reduce the technology’s cost by improving technical performance, establishing supply chains, and achieving economies of scale,” Shazan Siddiqi, an analyst at UK-based research company IDTechEx, said in the online magazine.

At the Qianjiang site, experts told PV that the station can be powered up and down more than 300 times a year. The stored electricity can be released to support the grid during peak times. Datang Group said the system can reduce harmful air pollution output by more than 13,000 tons each year.

Breathing high amounts of pollution can increase the chances for a host of health problems, from increased cancer risks to asthma and even dementia, according to health experts.

At Datang, the team is also touting other impressive metrics as part of its pollution-curbing solution.

“Sodium-ion batteries have excellent safety and low-temperature operating performance. They can still guarantee 85% charge and discharge efficiency at (minus 68-degrees Fahrenheit), which is unmatched by other batteries. They can also guarantee 1,500 charge and discharge cycles at a high temperature of (140-degrees),” Datang project manager Cui Yongle said in the PV article.

It’s another boon for the burgeoning renewable power and storage sector, as huge solar farms and other projects are being turned on or are in development in China, the U.S., Portugal, and elsewhere.

You can leverage steep tax breaks to install smaller, home-based systems and battery storage units. Installing solar can save you $1,500 a year on electricity bills, if canceling $125 worth of energy each month. Tax rebates, on average, are worth $4,600.

EnergySage and Rewiring America are free online tools that can help you navigate solar and battery options, applicable tax incentives, and even find an installer.

“An alternative from an abundantly available and cheaper source makes the transition easier,” IE’s Paleja noted, referencing the sodium science.