When a battery is used, electrically charged ions travel between electrodes, causing those electrodes to shrink and swell. For some time, researchers have wondered why the electrode materials – which are fairly brittle – don’t crack in the expansion and contraction styles.

Now, a team of researchers from MIT, led by ECS member Yet-Ming Chiang, may have found the answer to this mystery.

This from MIT:

While the electrode materials are normally crystalline, with all their atoms neatly arranged in a regular, repetitive array, when they undergo the charging or discharging process, they are transformed into a disordered, glass-like phase that can accommodate the strain of the dimensional changes.

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A newly created material may have the capacity to double the efficiency of solar cells.

Conventional solar cells are at most one-third efficient, a limit known to scientists as the Shockley-Queisser Limit. The new material, a crystalline structure that contains both inorganic materials (iodine and lead) and an organic material (methyl-ammonium), boosts the efficiency so that it can carry two-thirds of the energy from light without losing as much energy to heat.

In less technical terms, this material could double the amount of electricity produced without a significant cost increase, according to the new study in Science.

Enough solar energy reaches the earth to supply all of the planet’s energy needs multiple times over, but capturing that energy has been difficult—as of 2013, only about 1 percent of the world’s grid electricity was produced from solar panels.

The new material, called a hybrid perovskite, would create solar cells thinner than conventional silicon solar cells, and is also flexible, cheap, and easy to make, says Libai Huang, assistant professor of chemistry at Purdue University.

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A new mathematical model may help researchers design new materials for use in high-power batteries. According to the research team, the model could benefit chemists and materials scientists who typically rely on a trial and error method when developing new materials for batteries and capacitors.

“The potential here is that you could build batteries that last much longer and make them much smaller,” says Daniel Tartakovsky, co-author of the study. “If you could engineer a material with a far superior storage capacity than what we have today, then you could dramatically improve the performance of batteries.”

Demand for affordable, efficient energy storage continues to increase as more entities transition toward renewable energy. While there are many researchers working in the area of energy storage, the team behind this development is looking at the field in a new light.

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A team of scientists from Oak Ridge National Laboratory is using the precision of an electron beam to instantly adhere cathode coatings for lithium-ion batteries. This new development, as reported in the Journal of The Electrochemical Society, could lead to a leap in efficiency that saves energy, reduces production cost, and eliminates the use of toxic solvents.

This from ORNL:

The technique uses an electron beam to cure coating material as it rolls down the production line, creating instantaneous cross-links between molecules that bind the coating to a foil substrate, without the need for solvents, in less than a second.

Read the full article.

“Typical curing processes can require drying machinery the length of a football field and expensive equipment for solvent recovery,” says David Wood, co-author of the study. “This approach presents a promising avenue for fast, energy-efficient manufacturing of high-performance, low-cost lithium-ion batteries.”

Read the full paper, “Electron Beam Curing of Composite Positive Electrode for Li-Ion Battery.”

Joint research from the Universidad Carlos III de Madrid and the Council for Scientific Research reports the development of a new ceramic electrode for lithium-ion batteries that can lead to cheaper, more efficient, and safer conventional batteries.

“What we have patented are new ceramic electrodes that are much safer and can work in a wider temperature interval,” says Alejandro Varez, co-author of the research.

To achieve this result, the researchers made ceramic sheets by way of thermoplastic extrusion molds.

“This technique allows making electrodes that are flat or tube-shaped, and these electrodes can be applied to any type of lithium-ion battery,” Varez says.

According to the researchers, the cost of production is low and it could easily be adapted into current lithium-ion battery production, making this an easy technology to move quickly to industrialization.

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Image: Kathy F. Atkinson, University of Delaware

Fuel cells are an important technology for the nation’s energy portfolio, offering a cleaner, more efficient alternative to combustion engines that utilize fossil fuels.

However, a team of researchers from the University of Delaware point out that a major challenge in the commercialization of fuel cells is the durability of the membrane, which tends to develop cracks that short is life during operation.

A new article published in the Journal of The Electrochemical Society, “Self-Healing Composite Membrane for Proton Electrolyte Membrane Fuel Cell Applications,” aims to address the fuel cell membrane issue by developing a self-healing membrane, incorporating microcapsules prefilled with a Nafion solution.

“The microcapsules are designed to rupture when they encounter defects in the membrane and then release the prefilled Nafion solution to heal the defects in place,” says Liang Wang, past ECS member and co-author of the study.

Testing showed that the newly developed membrane and its self-healing functionality could greatly extend its useful life.

By: Joshua D. Rhodes, University of Texas at Austin

The electric grid is an amazing integrated system of machines spanning an entire continent. The National Academy of Engineering has called it one of the greatest engineering achievements of the 20th century.

But it is also expensive. By my analysis, the current (depreciated) value of the U.S. electric grid, comprising power plants, wires, transformers and poles, is roughly US$1.5 to $2 trillion. To replace it would cost almost $5 trillion.

That means the U.S. electric infrastructure, which already contains trillions of dollars of sunk capital, will soon need significant ongoing investment just to keep things the way they are. A power plant built during the rapid expansion of the power sector in the decades after World War II is now 40 years old or older, long paid off, and likely needs to be replaced. In fact, the American Society of Civil Engineers just gave the entire energy infrastructure a barely passing grade of D+.

The current administration has vowed to invest heavily in infrastructure, which raises a number of questions with regard to the electric system: What should the energy grid of the future look like? How do we achieve a low-carbon energy supply? What will it cost?

Infrastructure seems to be an issue that can gather support from both sides of the aisle. But to make good decisions on spending, we need first to understand the value of the existing grid.

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Every year on March 22, people around the globe celebrate World Water Day to advocate for improved access to clean water internationally. To date, there are over 663 million people living without a safe water supply close to home, leading to families spending countless hours retrieving water from distant sources or coping with the health impacts of using contaminated water.

This year, the theme of World Water Day is “Wastewater.” According to the World Health Organization, over 80 percent of wastewater flows back into nature, polluting the environment and wasting what could be a recycled resource. By exploring wastewater and finding ways to safely manage and recycle it, a sustainable source of water, energy, and nutrients could be recovered.

Critical gaps in water and sanitation

For ECS members, wastewater treatment and efforts to improve access to clean water in the developing world is familiar territory.

In 2014, ECS partnered with the Bill & Melinda Gates Foundation to establish the first Science for Solving Society’s Problems challenge, leveraging the brainpower of scientists from around the world to create innovative solutions to some of the most pressing problems in global water and sanitation.

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Chemists have engineered a molecule that uses light or electricity to convert carbon dioxide into carbon monoxide—a carbon-neutral fuel source—more efficiently than any other method of “carbon reduction.”

“If you can create an efficient enough molecule for this reaction, it will produce energy that is free and storable in the form of fuels,” says study leader and Liang-shi Li, associate professor in the chemistry department at Indiana University Bloomington. “This study is a major leap in that direction.”

Burning fuel—such as carbon monoxide—produces carbon dioxide and releases energy. Turning carbon dioxide back into fuel requires at least the same amount of energy. A major goal among scientists has been decreasing the excess energy needed.

This is exactly what Li’s molecule achieves: requiring the least amount of energy reported thus far to drive the formation of carbon monoxide. The molecule—a nanographene-rhenium complex connected via an organic compound known as bipyridine—triggers a highly efficient reaction that converts carbon dioxide to carbon monoxide.

The ability to efficiently and exclusively create carbon monoxide is significant due to the molecule’s versatility.

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Reports of a woman’s headphones catching fire while on a flight from Bejing to Melbourne has once again heightened interest in lithium-ion battery safety. According to the Australian Transport Safety Bureau, the incident occurred while the woman was sleeping mid-flight wearing battery-powered headphones.

Early in 2016, battery expert and ECS fellow, K.M. Abraham, talked to ECS about lithium-ion battery safety concerns amidst reports of exploding hoverboards. Below are some excerpts of what he had to say.

“It is safe to say that these well-publicized hazardous events are rooted in the uncontrolled release of the large amount of energy stored in lithium-ion batteries as a result of manufacturing defects, inferior active and inactive materials used to build cells and battery packs, substandard manufacturing and quality control practices by a small fraction of cell manufacturers, and user abuses of overcharge and over-discharge, short-circuit, external thermal shocks and violent mechanical impacts,” Abraham told ECS. “All of these mistreatments can lead lithium-ion batteries to thermal runaway reactions accompanied by the release of hot combustible organic solvents which catch fire upon contact with oxygen in the atmosphere.”

Read Abraham’s full article.

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