Superior high-voltage performance of Li-ion full cell with Li-rich layered oxide cathode prepared with fluorinated polyimide (FPI) binder, compared to the cell with conventional binder PVdF. (Click to enlarge.)
Image: Seung Wan Song

In order to increase the driving range of electric vehicles, researchers across the globe are working to develop lithium-ion batteries with higher energy storage. Now, scientists at Chungnam National University and Kumoh National Institute of Technology in Korea are taking a step toward that goal with their development of the first high-voltage cathode binder for higher energy Li-ion batteries.

Today’s Li-ion batteries are limited to charge to 4.2V due to the electrochemical instability of the liquid electrolyte and cathode-electrolyte interface, and loosening of conventional binder, polyvinylidenefluoride (PVdF), particularly at elevated temperatures. The fabrication of Li-rich layered oxide cathode with a novel high-voltage binder, as the research team demonstrated, can overcome these limitations.

Charging the batteries with Li-rich layered oxide cathode (xLi₂MnO₃∙(1−x)LiMO2, M = Mn, Ni, Co) to higher than 4.5V produces approximately doubled capacity than those with LiCoO₂ cathode, so that doubled energy density batteries can be achieved.

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New research from Sandia National Laboratory is moving toward advancing solid state lithium-ion battery performance in small electronics by identifying major obstacles in how lithium ions flow across battery interfaces.

The team of researchers, including ECS member Forrest Gittleson, looked at the nanoscale chemistry of solid state batteries, focusing on the area where the electrodes and electrolytes make contact.

“The underlying goal of the work is to make solid-state batteries more efficient and to improve the interfaces between different materials,” says Farid El Gabaly, coauthor of the recently published work. “In this project, all of the materials are solid; we don’t have a liquid-solid interface like in traditional lithium-ion batteries.”

According to El Gabaly, the faster the lithium can travel from one electrode to the other, the more efficient the batteries could be.

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Capitalizing on tiny defects can improve electrodes for lithium-ion batteries, new research suggests.

In a study on lithium transport in battery cathodes, researchers found that a common cathode material for lithium-ion batteries, olivine lithium iron phosphate, releases or takes in lithium ions through a much larger surface area than previously thought.

“We know this material works very well but there’s still much debate about why,” says Ming Tang, an assistant professor of materials science and nanoengineering at Rice University. “In many aspects, this material isn’t supposed to be so good, but somehow it exceeds people’s expectations.”

Part of the reason, Tang says, comes from point defects—atoms misplaced in the crystal lattice—known as antisite defects. Such defects are impossible to completely eliminate in the fabrication process. As it turns out, he says, they make real-world electrode materials behave very differently from perfect crystals.

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Safety concerns regarding lithium-ion batteries have been making headlines in light of smartphone fires and hoverboard explosions. In order to combat safety issues, at team of researchers from Drexel University, led by ECS member Yury Gogotsi, has developed a way to transform a battery’s electrolyte solution into a safeguard against the chemical process that leads to battery fires.

Dendrites – or battery buildups caused by the chemical reactions inside the battery – have been cited as one of the main causes of lithium-ion battery malfunction. As more dendrites compile over time, they can breach the battery’s separator, resulting in malfunction.

(MORE: Read more research by Gogotsi in the ECS Digital Library.)

As part of their solution to this problem, the research team is using nanodiamonds to curtail the electrochemical deposition that leads to the short-circuiting of lithium-ion batteries. To put it in perspective, nanodiamond particles are roughly 10,000 times smaller than the diameter of a single hair.

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Researchers have found a new method for finding lithium, used in the lithium-ion batteries that power modern electronics, in supervolcanic lake deposits.

While most of the lithium used to make batteries comes from Australia and Chile, but scientists say there are large deposits in sources right here in America: supervolcanoes.

In a recently published study, scientists detail a new method for locating lithium in supervolcanic lake deposits.

The findings represent an important step toward diversifying the supply of this valuable silvery-white metal, since lithium is an energy-critical strategic resource, says study coauthor Gail Mahood, a professor of geological sciences at Stanford University’s School of Earth, Energy & Environmental Sciences.

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In May 2017 during the 231st ECS Meeting, we sat down with Doron Aurbach, professor at Bar-Ilan University in Israel, to discuss his life in science, the future of batteries, and scientific legacy. The conversation was led by Rob Gerth, ECS’s director of marketing and communications.

During the 231st ECS Meeting, Aurbach received the ECS Allen J. Bard Award in Electrochemical Science for his distinguished contributions to the field. He has published more than 540 peer-reviewed papers, which have received more than 37,000 citations. Doron serves as a technical editor for the Journal of The Electrochemical Society and is an ECS fellow. His work in fundamental battery research has received recognition world-wide.

Listen to the podcast and download this episode and others for free on Apple Podcasts, SoundCloud, Podbean, or our RSS Feed. You can also find us on Stitcher and Acast.

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Lithium-ion batteries power a vast majority of the world’s portable electronics, from smartphones to laptops. A standard lithium-ion batteries utilizes a liquid as the electrolyte between two electrodes. However, the liquid electrolyte has the potential to lead to safety hazards. Researchers from MIT believe that by using a solid electrolyte, lithium-ion batteries could be safer and able to store more energy. However, most research in the area of all-solid-state lithium-ion batteries has faced significant barriers.

According to the team from MIT, a reason why research into solid electrolytes has been so challenging is due to incorrect interpretation of how these batteries fail.

This from MIT:

The problem, according to this study, is that researchers have been focusing on the wrong properties in their search for a solid electrolyte material. The prevailing idea was that the material’s firmness or squishiness (a property called shear modulus) determined whether dendrites could penetrate into the electrolyte. But the new analysis showed that it’s the smoothness of the surface that matters most. Microscopic nicks and scratches on the electrolyte’s surface can provide a toehold for the metallic deposits to begin to force their way in, the researchers found.

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In an effort to expand South Australia’s renewable energy supply, the state has looked to business magnate Elon Musk to build the world’s largest lithium-ion battery. The goal of the project is to deliver a grid-scale battery with the ability to stabilize intermittency issues in the area as well as reduce energy prices.

An energy grid is the central component of energy generation and usage. By changing the type of energy that powers that grid in moving from fossil fuels toward more renewable sources, the grid itself changes. Traditional electrical grids demand consistency, using fossil fuels to control production for demand. However, renewable sources such as wind and solar provide intermittency issues that traditional fossil fuels do not. Researchers must look at how we can deliver energy to the electrical grid when the sun goes down or the wind stops blowing. This is where energy storage systems, such as batteries, play a pivotal role.

In South Australia, Musk’s battery is intended to sustain 100 megawatts of power and store that energy for 129 megawatt hours. To put it in perspective, that is enough energy to power 30,000 homes and, according to Musk, will be three times as powerful as the world’s current largest lithium-ion battery.

Musk hopes to complete the project by December, stating that “It’s a fundamental efficiency improvement to the power grid, and it’s really quite necessary and quite obvious considering a renewable energy future.”

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A new development in electrolyte chemistry, led by ECS member Shirley Meng, is expanding lithium-ion battery performance, allowing devices to operate at temperatures as low as -60° Celsius.

Currently, lithium-ion batteries stop operating around -20° Celsius. By developing an electrolyte that allows the battery to operate at a high efficiency at a much colder temperature, researchers believe it could allow electric vehicles in cold climates to travel further on a single charge. Additionally, the technology could allow battery-powered devices, such as WiFi drones, to function in extreme cold conditions.

(MORE: Read ECS’s interview with Meng, “The Future of Batteries.”)

This from UC San Diego:

The new electrolytes also enable electrochemical capacitors to run as low as -80 degrees Celsius — their current low temperature limit is -40 degrees Celsius. While the technology enables extreme low temperature operation, high performance at room temperature is still maintained. The new electrolyte chemistry could also increase the energy density and improve the safety of lithium batteries and electrochemical capacitors.

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In an effort to increase security on airplanes, the U.S. government is considering expanding a ban on lithium-ion based devices from cabins of commercial flights, opting instead for passengers to transport laptops and other electronic devices in their checked luggage in the cargo department. However, statistics from the Federal Aviation Administration suggest that storing those devices in the cargo area could increase the risk of fires.

The FAA reports that batteries were responsible for nine airline fires in 2014. The number grew to 16 in 2015 and further to 31 in 2016. Most fires were able to be extinguished by passengers.
According to Homeland Security Secretary John Kelly, the U.S. government is considering expanding the ban to 71 additional airports.

(READ: “What’s Next for Batteries?” with Robert Kostecki.)

Mainstream concern regarding lithium-ion battery safety became widespread in 2016 when videos of hoverboards exploding began to emerge. Since then, news reports of smartphone and laptop batteries have emerged.

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