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Ames Lab Scientists' Surprising Discovery: Making Ferromagnets Stronger by Adding Non-Magnetic Element

Researchers at the U.S. Department of Energy's Ames Laboratory discovered that they could functionalize magnetic materials through a thoroughly unlikely method, by adding amounts of the virtually non-magnetic element scandium to a gadolinium-germanium alloy. It was so unlikely they called it a "counterintuitive experimental finding" in their published work on the research.

Cut U.S. Commercial Building Energy Use 29% with Widespread Controls

The U.S. could slash its energy use by the equivalent of what is currently used by 12 to 15 million Americans if commercial buildings fully used energy-efficiency controls nationwide.

How a Single Chemical Bond Balances Cells Between Life and Death

With SLAC's X-ray laser and synchrotron, scientists measured exactly how much energy goes into keeping a crucial chemical bond from triggering a cell's death spiral.

New Efficient, Low-Temperature Catalyst for Converting Water and CO to Hydrogen Gas and CO2

Scientists have developed a new low-temperature catalyst for producing high-purity hydrogen gas while simultaneously using up carbon monoxide (CO). The discovery could improve the performance of fuel cells that run on hydrogen fuel but can be poisoned by CO.

Study Sheds Light on How Bacterial Organelles Assemble

Scientists at Berkeley Lab and Michigan State University are providing the clearest view yet of an intact bacterial microcompartment, revealing at atomic-level resolution the structure and assembly of the organelle's protein shell. This work can help provide important information for research in bioenergy, pathogenesis, and biotechnology.

A Single Electron's Tiny Leap Sets Off 'Molecular Sunscreen' Response

In experiments at the Department of Energy's SLAC National Accelerator Laboratory, scientists were able to see the first step of a process that protects a DNA building block called thymine from sun damage: When it's hit with ultraviolet light, a single electron jumps into a slightly higher orbit around the nucleus of a single oxygen atom.

Researchers Find New Mechanism for Genome Regulation

The same mechanisms that separate mixtures of oil and water may also help the organization of an unusual part of our DNA called heterochromatin, according to a new study by Berkeley Lab researchers. They found that liquid-liquid phase separation helps heterochromatin organize large parts of the genome into specific regions of the nucleus. The work addresses a long-standing question about how DNA functions are organized in space and time, including how genes are silenced or expressed.

The Rise of Giant Viruses

Research reveals that giant viruses acquire genes piecemeal from others, with implications for bioenergy production and environmental cleanup.

Grasses: The Secrets Behind Their Success

Researchers find a grass gene affecting how plants manage water and carbon dioxide that could be useful to growing biofuel crops on marginal land.

SLAC Experiment is First to Decipher Atomic Structure of an Intact Virus with an X-ray Laser

An international team of scientists has for the first time used an X-ray free-electron laser to unravel the structure of an intact virus particle on the atomic level. The method dramatically reduces the amount of virus material required, while also allowing the investigations to be carried out several times faster than before. This opens up entirely new research opportunities.


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Chicago Quantum Exchange to Create Technologically Transformative Ecosystem

The University of Chicago is collaborating with the U.S. Department of Energy's Argonne National Laboratory and Fermi National Accelerator Laboratory to launch an intellectual hub for advancing academic, industrial and governmental efforts in the science and engineering of quantum information.

Department of Energy Awards Six Research Contracts Totaling $258 Million to Accelerate U.S. Supercomputing Technology

Today U.S. Secretary of Energy Rick Perry announced that six leading U.S. technology companies will receive funding from the Department of Energy's Exascale Computing Project (ECP) as part of its new PathForward program, accelerating the research necessary to deploy the nation's first exascale supercomputers.

Cynthia Jenks Named Director of Argonne's Chemical Sciences and Engineering Division

Argonne has named Cynthia Jenks the next director of the laboratory's Chemical Sciences and Engineering Division. Jenks currently serves as the assistant director for scientific planning and the director of the Chemical and Biological Sciences Division at Ames Laboratory.

Argonne-Developed Technology for Producing Graphene Wins TechConnect National Innovation Award

A method that significantly cuts the time and cost needed to grow graphene has won a 2017 TechConnect National Innovation Award. This is the second year in a row that a team at Argonne's Center for Nanoscale Materials has received this award.

Honeywell UOP and Argonne Seek Research Collaborations in Catalysis Under Technologist in Residence Program

Researchers at Argonne are collaborating with Honeywell UOP scientists to explore innovative energy and chemicals production.

Follow the Fantastic Voyage of the ICARUS Neutrino Detector

The ICARUS neutrino detector, born at Gran Sasso National Lab in Italy and refurbished at CERN, will make its way across the sea to Fermilab this summer. Follow along using an interactive map online.

JSA Awards Graduate Fellowships for Research at Jefferson Lab

Jefferson Sciences Associates announced today the award of eight JSA/Jefferson Lab graduate fellowships. The doctoral students will use the fellowships to support their advanced studies at their universities and conduct research at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) - a U.S. Department of Energy nuclear physics laboratory managed and operated by JSA, a joint venture between SURA and PAE Applied Technologies.

Muon Magnet's Moment Has Arrived

On May 31, the 50-foot-wide superconducting electromagnet at the center of the Muon g-2 experiment saw its first beam of muon particles from Fermilab's accelerators, kicking off a three-year effort to measure just what happens to those particles when placed in a stunningly precise magnetic field. The answer could rewrite scientists' picture of the universe and how it works.

Seven Small Businesses to Collaborate with Argonne to Solve Technical Challenges

Seven small businesses have been selected to collaborate with researchers at Argonne to address technical challenges as part of DOE's Small Business Vouchers Program.

JSA Names Charles Perdrisat and Charles Sinclair as Co-Recipients of its 2017 Outstanding Nuclear Physicist Prize

Jefferson Science Associates, LLC, announced today that Charles Perdrisat and Charles Sinclair are the recipients of the 2017 Outstanding Nuclear Physicist Prize. The 2017 JSA Outstanding Nuclear Physicist Award is jointly awarded to Charles Perdrisat for his pioneering implementation of the polarization transfer technique to determine proton elastic form factors, and to Charles Sinclair for his crucial development of polarized electron beam technology, which made such measurements, and many others, possible.


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Oxygen: The Jekyll and Hyde of Biofuels

Scientists are devising ways to protect plants, biofuels and, ultimately, the atmosphere itself from damage caused by an element that sustains life on earth.

The Rise of Giant Viruses

Research reveals that giant viruses acquire genes piecemeal from others, with implications for bioenergy production and environmental cleanup.

Grasses: The Secrets Behind Their Success

Researchers find a grass gene affecting how plants manage water and carbon dioxide that could be useful to growing biofuel crops on marginal land.

New Perspectives Into Arctic Cloud Phases

Teamwork provides insight into complicated cloud processes that are important to potential environmental changes in the Arctic.

Mountaintop Plants and Soils to Become Out of Sync

Plants and soil microbes may be altered by climate warming at different rates and in different ways, meaning vital nutrient patterns could be misaligned.

If a Tree Falls in the Amazon

For the first time, scientists pinpointed how often storms topple trees, helping to predict how changes in Amazonia affect the world.

Turning Waste into Fuels, Microbial Style

A newly discovered metabolic process linking different bacteria in a community could enhance bioenergy production.

Department of Energy Awards Six Research Contracts Totaling $258 Million to Accelerate U.S. Supercomputing Technology

Today U.S. Secretary of Energy Rick Perry announced that six leading U.S. technology companies will receive funding from the Department of Energy's Exascale Computing Project (ECP) as part of its new PathForward program, accelerating the research necessary to deploy the nation's first exascale supercomputers.

Electrifying Magnetism

Researchers create materials with controllable electrical and magnetic properties, even at room temperature.

One Step Closer to Practical Fast Charging Batteries

Novel electrode materials have designed pathways for electrons and ions during the charge/discharge cycle.


Developing Tools to Understand Lithium-Ion Battery Instabilities

Article ID: 673265

Released: 2017-04-19 13:05:27

Source Newsroom: Department of Energy, Office of Science

  • Credit: Image courtesy of Advanced Energy Materials

    Atomic force microscopy (AFM) can measure atomic-scale height variations on the surface of a material. This investigation has developed AFM techniques to study silicon (Si) battery electrode materials during charge-discharge cycling (left). The design of the thin film electrode allows the measurement of growth of the surface interface layer (SEI) (purple region in the right image) during the cycling; this approach allows extraction of the interface thickness from the overall electrode volume change (tan).

The Science

Wouldn’t it be nice if lithium-ion batteries lasted as long as a car? Scientists have proposed silicon as a high-capacity negative electrode for lithium-ion batteries. Unfortunately, the formation and thickening of interface layers on top of silicon electrodes degrades cell performance. The result? You have to replace the battery. Measurements of the thickness of the interface material, known as the solid-electrolyte interphase or SEI, vary by two orders of magnitude. In this research, scientists combined real-time atomic force microscopy, which can measure surface layer thicknesses, with electrochemical cycling and a carefully designed sample geometry to unambiguously measure the SEI evolve. The sample design facilitates clear separation of SEI thickness evolution from the volume changes of the underlying silicon electrode. The measurements can be used to benchmark models of SEI reaction kinetics for different electrolytes.

The Impact

To lengthen the life of lithium-ion batteries, we need to know how to combat SEI formation. This measurement capability is a vital step in new studies of SEI properties. The approach offers real-time measurement of SEI thickness evolution with nanometer precision. It will allow for effective study of electrolyte compositions and additives and their effect on cell performance.   

Summary

This research has developed new techniques for in situ measurements of the growth of solid-electrolyte interphase (SEI) layers on silicon electrodes. These interface changes are accompanied by volume expansion induced by transport of lithium into the silicon. For these investigations, the team fabricated thin film amorphous silicon electrodes in a configuration that allows unambiguous separation of the total thickness change into the contributions due to the growth of the SEI and from the change in the silicon volume. They assembled the electrodes into a custom-designed electrochemical cell, which they integrated with an atomic force microscope. The electrodes are subjected to charge-discharge (lithiation-delithiation) cycles at a sequence of constant potential values and the thickness measurements are made at each potential after equilibrium is reached. The team carried out experiments with two electrolytes: 1.2M lithium hexafluoro-phosphate (LiPF6) in ethylene carbonate (EC) and 1.2M LiPF6 in propylene carbonate (PC) – to investigate the influence of electrolyte composition on SEI evolution. The team observed that SEI formation occurs predominantly during the first charging cycle and the maximum SEI thickness is approximately 17 nm and 10 nm, respectively, for EC and PC electrolytes. The measurements also yield valuable information on how the silicon electrode’s expansion ratio and charge capacity vary with equilibrium potential. Both relationships display hysteresis (for example, the measurements show a dependence on whether the electrode is being charged or discharged), which is explained in terms of the evolution of stress in silicon electrodes due to the changing volume. This sample design and measurement capability open the door for clear determination of which components and variations result in performance improvements in high-capacity lithium-ion batteries.

 

Funding

This work was fully supported by a Department of Energy Experimental Program to Stimulate Competitive Research (EPSCoR) Implementation award.

Publications

I. Yoon, D.P. Abraham, B.L. Lucht, A.F. Bower, and P.R. Guduru, “In situ measurement of solid electrolyte interphase evolution on silicon anodes using atomic force microscopy.” Advanced Energy Materials 6(12), 1600099 (2016). [DOI 10.1002/aenm.201600099]