Surprising discovery could lead to better batteriesJanuary 12, 2018
UPTON, NY - A collaboration led by scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory has observed an unexpected phenomenon in lithium-ion batteries--the most common type of battery used to power cell phones and electric cars. As a model battery generated electric current, the scientists witnessed the concentration of lithium inside individual nanoparticles reverse at a certain point, instead of constantly increasing. This discovery, which was published on January 12 in the journal Science Advances, is a major step toward improving the battery life of consumer electronics.
"If you have a cell phone, you likely need to charge its battery every day, due to the limited capacity of the battery's electrodes," said Esther Takeuchi, a SUNY distinguished professor at Stony Brook University and a chief scientist in the Energy Sciences Directorate at Brookhaven Lab. "The findings in this study could help develop batteries that charge faster and last longer."
Visualizing batteries on the nanoscale
Inside every lithium-ion battery are particles whose atoms are arranged in a lattice--a periodic structure with gaps between the atoms. When a lithium-ion battery supplies electricity, lithium ions flow into empty sites in the atomic lattice.
"Previously, scientists assumed that the concentration of lithium would continuously increase in the lattice," said Wei Zhang, a scientist at Brookhaven's Sustainable Energy Technologies Department. "But now, we have seen that this may not be true when the battery's electrodes are made from nano-sized particles. We observed the lithium concentration within local regions of nanoparticles go up, and then down--it reversed."
Electrodes are often made from nanoparticles in order to increase a battery's power density. But scientists have not been able to fully understand how these electrodes function, due to a limited ability to watch them work in action. Now, with a unique combination of experimental tools, the scientists were able to image reactions inside the electrodes in real time.
Similar to how a sponge soaks up water, we can see the overall level of lithium continuously increase inside the nano-sized particles," said Feng Wang, the leader of this study and a scientist in Brookhaven's Sustainable Energy Technologies Department. "But unlike water, lithium may preferentially move out of some areas, creating inconsistent levels of lithium across the lattice."
The scientists explained that uneven movement of lithium could have lasting, damaging effects because it strains the structure of the active materials in batteries and can lead to fatigue failure.
"Before lithium enters the lattice, its structure is very uniform," Wang said. "But once lithium goes in, it stretches the lattice, and when lithium goes out, the lattice shrinks. So each time you charge and drain a battery, its active component will be stressed, and its quality will degrade over time. Therefore, it is important to characterize and understand how lithium concentration changes both in space and time."
Combining tools of the trade
In order to make these observations, the scientists combined transmission electron microscopy (TEM) experiments--conducted at the Center for Functional Nanomaterials (CFN), a DOE Office of Science User Facility at Brookhaven Lab, and at Brookhaven's Condensed Matter Physics and Materials Science Department--with x-ray analyses at the National Synchrotron Light Source (NSLS), a DOE Office of Science user facility at Brookhaven that closed in 2014 when its successor, NSLS-II, opened.
"Wang's team combined TEM with x-ray techniques," said Yimei Zhu, co-author of the study and a senior physicist at Brookhaven Lab. "Both methods use a similar approach to analyze the structure of materials, but can provide complementary information. Electrons are sensitive to the local structure, while x-rays can probe a larger volume and enable much better statistics."
The Brookhaven team also developed a nanoscale model battery that could mimic the function of lithium-ion batteries that would "fit" into a TEM. Computer simulations conducted at the University of Michigan further confirmed the surprising conclusions.
"We initially thought that the reversal mechanism was similar to those previously proposed, which stemmed from the interactions between nearby particles," said Katsuyo Thornton, a professor of materials science and engineering at the University of Michigan, Ann Arbor, who led the theoretical effort. "However, it turned out a concentration reversal within a single particle could not be explained by existing theories, but rather, it arises from a different mechanism. Simulations were critical in this work because, without them, we would have made an incorrect conclusion."
While the study focused on lithium-ion batteries, the scientists say the observed phenomenon may also occur in other high-performance battery chemistries.
"Down the road, we plan to use the world-class facilities at CFN and NSLS-II to more closely examine how battery materials work, and to find solutions for building new batteries that can charge faster and last longer," Wang said. "These facilities offer the ideal tools for imaging the structure of battery materials in real time and under real-world conditions."
Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.
Follow @BrookhavenLab on Twitter or find us on Facebook.
DOE/Brookhaven National Laboratory
Related Nanoparticles Articles:
A team of chemists led by Carnegie Mellon's Rongchao Jin has for the first time conducted site-specific surgery on a nanoparticle.
The way that nanoparticles behave in the environment is extremely complex.
KAUST researchers reveal how small organic 'citrate' ions can stabilize gold nanoparticles, assisting research on the structures' potential.
Twenty-five years have passed since the publication of the first work on solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) as a system for delivering drugs.
In shampoo ads, hair always looks like a shiny, smooth surface.
Scientists at the University of Basel have developed nanoparticles which can serve as efficient contrast agents for magnetic resonance imaging.
Cancer treatments based on laser irridation of tiny nanoparticles that are injected directly into the cancer tumor are working and can destroy the cancer from within.
Zap a tumor with radiation to trigger expression of a molecule, then attack that molecule with a drug-loaded nanoparticle.
Use of nanoparticles in many applications, e.g. for catalysis, relies on the surface area of the particles.
Scientists have devised a triple-stage 'cluster bomb' system for delivering the chemotherapy drug cisplatin, via tiny nanoparticles designed to break up when they reach a tumor.
Related Nanoparticles Reading:
Gold Nanoparticles for Physics, Chemistry and Biology
by Catherine Louis (Author), Catherine Louis (Editor), Olivier Pluchery (Editor)
Gold Nanoparticles for Physics, Chemistry and Biology offers an overview of recent research into gold nanoparticles, covering their discovery, usage and contemporary practical applications.
This Second Edition begins with a history of over 2000 years of the use of gold nanoparticles, with a review of the specific properties which make gold unique. Updated chapters include gold nanoparticle preparation methods, their plasmon resonance and thermo-optical properties, their catalytic properties and their future technological applications. New chapters have been included, and reveal... View Details
Nanoparticles: From Theory to Application
by GÃ¼nter Schmid (Editor)
Very small particles are able to show astonishing properties. For example, gold atoms can be combined like strings of pearls, while nanoparticles can form one-, two- and three-dimensional layers. These assemblies can be used, for instance, as semiconductors, but other electronic as well as optical properties are possible.
An introduction to the booming field of "nanoworld" or "nanoscience", from fundamental principles to their use in novel applications.
With its clear structure and comprehensive coverage, backed by numerous examples from recent literature, this is a prime reference... View Details
Nanoparticles (De Gruyter Textbook)
by Raz Jelinek (Author)
Nanoparticles presents the variety of nanoparticle families, structures, and functions. The book discusses nanoparticles made of semiconductors, metals, metal-oxides, organics, biological and hybrid constituents. Through a wealth of examples and case studies, readers that are not necessarily active or experts in this area acquire a broad overview of this exciting field at the interface between scientific research and practical technologies.View Details
Nanoparticles - Nanocomposites Â– Nanomaterials: An Introduction for Beginners
by Dieter Vollath (Author)
Meeting the demand for a readily understandable introduction to nanomaterials and nanotechnology, this textbook specifically addresses the needs of students - and engineers - who need to get the gist of nanoscale phenomena in materials without having to delve too deeply into the physical and chemical details.
The book begins with an overview of the consequences of small particle size, such as the growing importance of surface effects, and covers successful, field-tested synthesis techniques of nanomaterials. The largest part of the book is devoted to the particular magnetic, optical,... View Details
Gas Phase Nanoparticle Synthesis
by Claes Granqvist (Editor), Laszlo Kish (Editor), William Marlow (Editor)
This book deals with gas-phase nanoparticle synthesis and is intended for researchers and research students in nanomaterials science and engineering, condensed matter physics and chemistry, and aerosol science. Gas-phase nanoparticle synthesis is instrumental to nanotechnology - a field in current focus that raises hopes for environmentally benign, resource-lean manufacturing. Nanoparticles can be produced by many physical, chemical, and even biological routes. Gas-phase synthesis is particularly interesting since one can achieve accurate manufacturing control and hence industrial viability.... View Details
Formulation and process variables influencing nanoparticles properties: Factors influencing properties of nanoparticles prepared by nanoprecipitation and emulsification-based methods
by Maja Simonoska Crcarevska (Author), Marija Glavas Dodov (Author), Nikola Lazarevski (Author)
Having in mind the toxicity of certain drugs, problems associated with multi drug resistance and favorable pharmacokinetic properties offered by nanoparticulated drug delivery systems (NDDS), it could be said that nanoencapsulation is a challengeable and interesting approach to achieve desired benefits of lower toxicity and increased drug accumulation into the target tissue/organ. The first step that needs to be mastered in the NDDS design, is to achieve prolonged blood circulation time by providing the adequate nanoparticle (NP) size... View Details
Studies on Metal & Metal Oxide Nanoparticles and Carbon Nanostructures: Metal Nanoparticles & C-Nanostructures
by Ashwani Kumar Singh (Author)
Metal nanoparticles exhibit unique optical, electronic and catalytic properties which are primarily based on their small size and their high surface to volume ratio. The properties of these materials are often different from corresponding bulk materials of the same kind and are usually influenced by the particle size. Developments of metal/metal oxide nanostructures, which can be synthesized by cost effective synthesis methods and with well-defined morphologies, have attracted considerable interest. The structural, microstructural characteristics, properties and their inter-relationship lead... View Details
Metal Nanoparticles in Pharma
by Mahendra Rai Ph.D (Editor), Ranjita Shegokar Ph.D (Editor)
Completely dedicated to the biomedical applications of metal nanoparticles, this book covers the different toxicity problems found in healthcare situations and also provides comprehensive info on the use of metal nanoparticles in treating various diseases. Metal Nanoparticles in Pharma is the first edited volume to set up the discussion for a clinical setting and to target a pharmaceutical audience of academic and industry-based researchers. View Details
Bio-Nanoparticles: Biosynthesis and Sustainable Biotechnological Implications
by Om V. Singh (Editor)
Nanoparticles are the building blocks for nanotechnology; they are better built, long lasting, cleaner, safer, and smarter products for use across industries, including communications, medicine, transportation, agriculture and other industries. Controlled size, shape, composition, crystallinity, and structure-dependent properties govern the unique properties of nanotechnology.
Bio-Nanoparticles: Biosynthesis and Sustainable Biotechnological Implications explores both the basics of and advancements in nanoparticle biosynthesis. The text introduces the reader to a variety of... View Details
Characterization of Nanoparticles Intended for Drug Delivery (Methods in Molecular Biology)
by Scott E. McNeil (Editor)
This second edition volume expands on the first edition by providing up-to-date protocols to characterize nanomaterials used as drug delivery agents. The chapters in this book are divided into 5 parts and cover topics such as: advances and obstacles in nanomedicine research; methods to test sterility and endotoxin, physicochemical features, immunological effects, drug release, and in vivo efficacy. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents,... View Details