Name: characterization of electrode materials for lithium ion and sodium ion batteries using synchrotron radiation techniques
Uploaded: 2013-11-11T19:45:00
Description: Watch this Scientific Journal Video about Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques at JoVE.com

This work is supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Portions of this research were carried out at the Stanford Synchrotron Radiation Lightsource, a Directorate of SLAC National Accelerator Laboratory and an Office of Science User Facility operated for the U.S. Department of Energy Office of Science by Stanford University. The SSRL Structural Molecular Biology Program is supported by the DOE Office of Biological and Environmental Research, and by the National Institutes of Health, National Center for Research Resources, Biomedical Technology Program (P41RR001209).

1. Planning of Experiments
<ol>
	<li>Identify beam line experiments of interest. Refer to beam line webpages as guides. For SSRL XAS and XRD, these are: <a href="http://www-ssrl.slac.stanford.edu/beamlines/bl4-1/" target="_blank">http://www-ssrl.slac.stanford.edu/beamlines/bl4-1/</a> and <a href="http://www-ssrl.slac.stanford.edu/beamlines/bl4-3/" target="_blank">http://www-ssrl.slac.stanford.edu/beamlines/bl4-3/</a> and <a href="http://www-ssrl.slac.stanford.edu/beamlines/bl11-3/" target="_blank">http://www-ssrl.slac....

<ol>
	<li>Kim, S. -. W., Seo, D. -. I., Ma, X., Ceder, G., Kang, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrode+Materials+for+Rechargeable+Sodium-Ion+Batteries:+Potential+Alternatives+to+Current+Lithium-Ion+Batteries.">Electrode Materials for Rechargeable Sodium-Ion Batteries: Potential Alternatives to Current Lithium-Ion Batteries.</a> Adv. Energy Mater. 2, 710-721 (2012).</li><li>Palomares, V., Serras, P., Villaluenga, I., Huesa, K. B., Cerretero-Gonzalez, J., Rojo, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Na-ion+Batteries,+Recent+Advances+and+Present+Challenges+to+Become+Low+Cost+Energy+Storage+Systems.">Na-ion Batteries, Recent Advances and Present Challenges to Become Low Cost Energy Storage Systems.</a> Energy Environ. Sci. 5, 5884-5901 (2012).</li><li>Kam, K. C., Doeff, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrode+Materials+for+Lithium+Ion+Batteries.">Electrode Materials for Lithium Ion Batteries.</a> Materials Matters. 7, 56-60 (2012).</li><li>Cabana, J., Monconduit, L., Larcher, D., Palacin, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Beyond+Intercalation-Based+Li-Ion+Batteries:+The+State+of+the+Art+and+Challenges+of+Electrode+Materials+Reacting+Through+Conversion+Reactions.">Beyond Intercalation-Based Li-Ion Batteries: The State of the Art and Challenges of Electrode Materials Reacting Through Conversion Reactions.</a> Adv. Energy Mater. 22, E170-E192 (2010).</li><li>McBreen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Application+of+Synchrotron+Techniques+to+the+Study+of+Lithium+Ion+Batteries.">The Application of Synchrotron Techniques to the Study of Lithium Ion Batteries.</a> J. Solid State Electrochem. 13, 1051-1061 (2009).</li><li>de Groot, F., Vank&#243;, G., Glatzel, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+1s+X-ray+Absorption+Pre-edge+Structures+in+Transition+Metal+Oxides.">The 1s X-ray Absorption Pre-edge Structures in Transition Metal Oxides.</a> J. Phys. Condens. Matter. 21, 104207 (2009).</li><li>Rumble, C., Conry, T. E., Doeff, M., Cairns, E. J., Penner-Hahn, J. E., Deb, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+and+Electrochemical+Investigation+of+Li(Ni0.4Co0.15Al0.05Mn0.4)O2.">Structural and Electrochemical Investigation of Li(Ni0.4Co0.15Al0.05Mn0.4)O2.</a> J. Electrochem. Soc. 157, A1317-A1322 (2010).</li><li>Cabana, J., Dupr&#233;, N., Gillot, F., Chadwick, A. V., Grey, C. P., Palac&#237;n, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis,+Short-Range+Structure+and+Electrochemical+Properties+of+New+Phases+in+the+Li-Mn-N-O+System.">Synthesis, Short-Range Structure and Electrochemical Properties of New Phases in the Li-Mn-N-O System.</a> Inorg. Chem. 48, 5141-5153 (2009).</li><li>Ravel, B., Newville, M. A. T. H. E. N. A., ARTEMIS, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=HEPHAESTUS:+data+analysis+for+X-ray+absorption+spectroscopy+using+IFEFFIT.">HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT.</a> Journal of Synchrotron Radiation. 12, 537-541 (2005).</li><li>Zeng, D., Cabana, J. B. r. &. #. 2. 3. 3. ;. g. e. r., Yoon, W. -. S., Grey, C. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cation+Ordering+in+Li[NixMnxCo(1–2x)]O2-Layered+Cathode+Materials:+A+Nuclear+Magnetic+Resonance+(NMR),+Pair+Distribution+Function,+X-ray+Absorption+Spectroscopy,+and+Electrochemical+Study.">Cation Ordering in Li[NixMnxCo(1–2x)]O2-Layered Cathode Materials: A Nuclear Magnetic Resonance (NMR), Pair Distribution Function, X-ray Absorption Spectroscopy, and Electrochemical Study.</a> Chem. Mater. 19, 6277-6289 (2007).</li><li>Conry, T. E., Mehta, A., Cabana, J., Doeff, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=XAFS+Investigation+of+LiNi0.45Mn0.45Co0.1-yAlyO2+Positive+Electrode+Materials.">XAFS Investigation of LiNi0.45Mn0.45Co0.1-yAlyO2 Positive Electrode Materials.</a> J. Electrochem. Soc. 159, A1562-A1571 .</li><li>Conry, T. E., Mehta, A., Cabana, J., Doeff, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+Underpinnings+of+the+Enhanced+Cycling+Stability+upon+Al-substitution+in+LiNi0.45Mn0.45Co0.1-yAlyO2+Positive+Electrode+Materials+for+Li-ion+Batteries.">Structural Underpinnings of the Enhanced Cycling Stability upon Al-substitution in LiNi0.45Mn0.45Co0.1-yAlyO2 Positive Electrode Materials for Li-ion Batteries.</a> Chem. Mater. 24, 3307-3317 (2012).</li><li>Reed, J., Ceder, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+Electronic+Structure+in+the+Susceptibility+of+Metastable+Transition-Metal+Oxide+Structures+to+Transformation.">Role of Electronic Structure in the Susceptibility of Metastable Transition-Metal Oxide Structures to Transformation.</a> Chem. Rev. 104, 4513-4534 (2004).</li><li>Cook, J. B., Kim, C., Xu, L., Cabana, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Effect+of+Al+Substitution+on+the+Chemical+and+Electrochemical+Phase+Stability+of+Orthorhombic+LiMnO2.">The Effect of Al Substitution on the Chemical and Electrochemical Phase Stability of Orthorhombic LiMnO2.</a> J. Electrochem. Soc. 160, A46-A52 (2013).</li><li>Lee, E., Persson, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Revealing+the+Coupled+Cation+Interactions+Behind+the+Electrochemical+Profile+of+LixNi0.5Mn1.5O4.">Revealing the Coupled Cation Interactions Behind the Electrochemical Profile of LixNi0.5Mn1.5O4.</a> Energy Environ. Sci. 5, 6047-6051 (2012).</li><li>Hai, B., Shukla, A. K., Duncan, H., Chen, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Effect+of+Particle+Surface+Facets+on+the+Kinetic+Properties+of+LiMn1.5Ni0.5O4+Cathode+Materials.">The Effect of Particle Surface Facets on the Kinetic Properties of LiMn1.5Ni0.5O4 Cathode Materials.</a> J. Mater. Chem. A. 1, 759-769 (2013).</li><li>Cabana, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Composition-Structure+Relationships+in+the+Li-Ion+Battery+Electrode+Material+LiNi0.5Mn1.5O4.">Composition-Structure Relationships in the Li-Ion Battery Electrode Material LiNi0.5Mn1.5O4.</a> Chem. Mater. 24, 2952-2964 (2012).</li><li>Liu, J., Kunz, M., Chen, K., Tamura, N., Richardson, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visualization+of+Charge+Distribution+in+a+Lithium+Battery+Electrode.">Visualization of Charge Distribution in a Lithium Battery Electrode.</a> J. Phys. Chem. Lett. 1, 2120-2123 (2010).</li><li>Meirer, F., Cabana, J., Liu, Y., Mehta, A., Andrews, J. C., Pianetta, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+Imaging+of+Chemical+Phase+Transformation+at+the+Nanoscale+with+Full-Field+Transmission+X-ray+Microscopy.">Three-dimensional Imaging of Chemical Phase Transformation at the Nanoscale with Full-Field Transmission X-ray Microscopy.</a> J. Synchrotron Rad. 18, 773-781 (2011).</li><li>Liu, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phase+Transformation+and+Lithiation+Effect+on+Electronic+Structure+of+LixFePO4:+An+In-Depth+Study+by+Soft+X-ray+and+Simulations.">Phase Transformation and Lithiation Effect on Electronic Structure of LixFePO4: An In-Depth Study by Soft X-ray and Simulations.</a> J. Am. Chem. Soc. 134, 13708-13715 (2012).</li><li>Sokaras, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+High+Resolution+and+Solid+Angle+X-ray+Raman+Spectroscopy+End-Station+at+the+Stanford+Synchrotron+Radiation+Lightsource.">A High Resolution and Solid Angle X-ray Raman Spectroscopy End-Station at the Stanford Synchrotron Radiation Lightsource.</a> Rev. Sci. Instrum. 83, 043112 (2012).</li><li>Chan, M. K. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure+of+Lithium+Peroxide.">Structure of Lithium Peroxide.</a> J. Phys. Chem. Lett. 2, 2483-2486 (2011).</li></ol>

Analysis of XANES data indicates that as-made LiNixCo1-2xMnxO2 (0.01&#8804;x&#8804;1) compounds contains Ni2+, Co3+, and Mn4+.10 A recent in situ XAS study on LiNi0.4Co0.15Al0.05Mn0.4O2 showed that Ni2+ was oxidized to Ni3+ and, ultimately, Ni4+ during delithiation, but that redox processes involving Co3+ contributed some capaci...

Lithium ion batteries for consumer electronics presently command an $11 billion market worldwide (<a href="http://www.marketresearch.com/David-Company-v3832/Lithium-Ion-Batteries-Outlook-Alternative-6842261/" target="_blank">http://www.marketresearch.com/David-Company-v3832/Lithium-Ion-Batteries-Outlook-Alternative-6842261/</a>) and are the premier choice for emerging vehicular applications such as plug-in hybrid electric vehicles (PHEVs) and electric vehicles (EVs). Analogs to these devices utilizing sodium ions rather than lithium are in earlier stages of development, but are considered attractive for large scale energy storage (i.e.&#160;grid applications) based on cost and supply security arguments1, 2. Both dual intercalation systems work on the same principle; alkali metal ions shuttle between two electrodes acting as host structures, which undergo insertion processes at different potentials. The electrochemical cells themselves are relatively simple, consisting of composite positive and negative electrodes on current collectors, separated by a porous membrane saturated with an electrolytic solution usually consisting of a salt dissolved in a mixture of organic solvents (Figure 1). Graphite and LiCoO2 are the most commonly employed negative and positive electrodes, respectively, for lithium ion batteries. Several alternative electrode materials have also been developed for specific applications, including variants of LiMn2O4 spinel, LiFePO4 with the olivine structure, and NMCs (LiNixMnxCo1-2xO2 compounds) for positives, and hard carbons, Li4Ti5O12, and alloys of lithium with tin for negatives3. High voltage materials like LiNi0.5Mn1.5O4, new high capacity materials such as layered-layered composites (e.g.&#160;xLi2MnO3&#183;(1-x)LiMn0.5Ni0.5O2), compounds with transition metals that can undergo multiple changes in redox states, and Li-Si alloy anodes are currently subjects of intense research, and, if successfully deployed, should raise practical energy densities of lithium ion cells further. Another class of materials, known as conversion electrodes, in which transition metal oxides, sulfides, or fluorides are reversibly reduced to the metallic element and a lithium salt, are also under consideration for use as battery electrodes (primarily as replacements for anodes)4. For devices based on sodium, hard carbons, alloys, NASICON&#160;structures, and titanates are being investigated for use as anodes and various transition metal oxides and polyanionic compounds as cathodes.
Because lithium ion and sodium ion batteries are not based on fixed chemistries, their performance characteristics vary considerably depending on the electrodes that are employed. The redox behavior of the electrodes determines the potential profiles, rate capabilities, and cycle lives of the devices. Conventional powder X-ray diffraction (XRD) techniques can be used for initial structural characterization of pristine materials and ex situ measurements on cycled electrodes, but practical considerations such as low signal strength and the relatively long times needed to collect data limit the amount of information that can be obtained on the discharge and charge processes. In contrast, the high brilliance and short wavelengths of synchrotron radiation (e.g.&#160;&#955;=0.97 &#197; at the Stanford Synchrotron Radiation Lightsource&#39;s beamline 11-3), combined with the use of high throughput image detectors, permit acquisition of high-resolution data on samples in as little as 10 sec. In situ work is performed in transmission mode on cell components undergoing charge and discharge in hermetically sealed pouches transparent to X-rays, without having to stop operation to acquire data. As a result, electrode structural changes can be observed as &#34;snapshots in time&#34; as the cell cycles, and much more information can be obtained than with conventional techniques.
X-ray absorption spectroscopy (XAS), also sometimes referred to as X-ray Absorption Fine Structure (XAFS) gives information about the local electronic and geometric structure of materials. In XAS experiments, the photon energy is tuned to the characteristic absorption edges of the specific elements under investigation. Most commonly for battery materials, these energies correspond to the K-edges (1s orbitals) of the transition metals of interest, but soft XAS experiments tuned to O, F, C, B, N and the L2,3 edges of first row transition metals are also sometimes carried out on ex situ samples5. The spectra generated by XAS experiments can be divided into several distinct regions, containing different information (see Newville, M., Fundamentals of XAFS,&#160;<a href="http://xafs.org/Tutorials?action=AttachFile&amp;do=get&amp;target=Newville_xas_fundamentals.pdf" target="_blank">http://xafs.org/Tutorials?action=AttachFile&#38;do=get&#38;target=Newville_xas_fundamentals.pdf</a>). The main feature, consisting of the absorption edge and extending about 30-50 eV beyond is the X-ray Absorption Near Edge Structure (XANES) region and indicates the ionization threshold to continuum states. This contains information about the oxidation state and coordination chemistry of the absorber. The higher energy portion of the spectrum is known as the Extended X-ray Absorption Fine Structure (EXAFS) region and corresponds to the scattering of the ejected photoelectron off neighboring atoms. Fourier analysis of this region gives short-range structural information such as bond lengths and the numbers and types of neighboring ions. Preedge features below the characteristic absorption energies of some compounds also sometimes appear. These arise from dipole forbidden electronic transitions to empty bound states for octahedral geometries, or dipole allowed orbital hybridization effects in tetrahedral ones and can often be correlated to the local symmetry of the absorbing ion (e.g.&#160;whether it is tetrahedrally or octahedrally coordinated)6.
XAS is a particularly useful technique for studying mixed metal systems such as NMCs to determine initial redox states and which transition metal ions undergo redox during delithiation and lithiation processes. Data on several different metals can be obtained rapidly in a single experiment and interpretation is reasonably straightforward. In contrast, Mossbauer spectroscopy is limited to only a few metals used in battery materials (primarily, Fe and Sn). While magnetic measurements can also be used to determine oxidation states, magnetic coupling effects can complicate interpretation particularly for complex oxides such as the NMCs.
Well-planned and -executed in situ and ex situ synchrotron XRD and XAS experiments give complementary information and allow a more complete picture to be formed of the structural changes occurring in electrode materials during normal battery operation than what can be obtained via conventional techniques. This, in turn, gives a greater understanding of what governs the electrochemical behavior of the devices.

<table border="1">
	<tbody>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Equipment</td>
		</tr>
		<tr>
			<td>Inert atmosphere glovebox</td>
			<td>Vacuum Atmospheres</td>
			<td>Custom order, contact vendors</td>
			<td>Used during cell assembly and to store alkali metals and moisture sensitive components. (<a href="http://vac-atm.com" target="_blank">http://vac-atm.com</a>)</td>
		</tr>
		<tr>
			<td>Inert atmosphere glovebox</td>
			<td>Mbraun</td>
			<td></td>
			<td>Various sizes (single, double) available, many options such as mini or heated antechambers oxygen/water removal systems, shelving, electrical feedthroughs, etc. (<a href="http://www.mbraunusa.com" target="_blank">http://www.mbraunusa.com</a>)</td>
		</tr>
		<tr>
			<td>X-ray powder diffractometer (XRD)</td>
			<td>Panalytical</td>
			<td>X&#39;Pert Powder</td>
			<td>X&#39;Pert is a modular system. Many accessories available for specialized experiments. (<a href="http://www.mbraunusa.com" target="_blank">www.panalytical.com</a>)</td>
		</tr>
		<tr>
			<td>X-ray powder diffractometer (XRD)</td>
			<td>Bruker</td>
			<td>Bruker D2 Phaser</td>
			<td>Bruker D2 Phaser is compact and good for routine powder analyses. (<a href="www.bruker.com" target="_blank">www.bruker.com</a>)</td>
		</tr>
		<tr>
			<td>Scanning Electron Microscope (SEM)</td>
			<td></td>
			<td>JSM7500F</td>
			<td>High resolution field emission scanning electron microscope with numerous customizable options. JEOL (<a href="http://www.jeolusa.com" target="_blank">http://www.jeolusa.com</a>) Low cost tabletop versions also available. Contact vendor for options.</td>
		</tr>
		<tr>
			<td>Pouch Sealer</td>
			<td>VWR</td>
			<td>11214-107</td>
			<td>Used to seal pouches for in situ work. (<a href="https://us.vwr.com/" target="_blank">https://us.vwr.com</a>)</td>
		</tr>
		<tr>
			<td>Manual crimping tool</td>
			<td>Pred Materials</td>
			<td>HSHCC-2016, 2025, 2032, 2320</td>
			<td>Used to seal coin cells. Match size to coin cell hardware. (<a href="http://www.predmaterials.com/" target="_blank">www.predmaterials.com</a>)</td>
		</tr>
		<tr>
			<td>Coin cell disassembling tool</td>
			<td>Pred Materials</td>
			<td>Contact vendor</td>
			<td>Used to take apart coin cells to recover electrodes for ex situ work. Needlenose pliers can also be used. Cover ends with Teflon tape to avoid shorting cells. (<a href="http://www.predmaterials.com/" target="_blank">www.predmaterials.com</a>)</td>
		</tr>
		<tr>
			<td>Film casting knives</td>
			<td>BYK Gardner</td>
			<td>4301, 4302, 4303, 4304,4305,2325, 2326,2327,2328, 2329</td>
			<td>Used to cast electrodes films from slurries. Different sizes available, with either metric or English gradations. Bar film or Baker-type applicators and doctor blades are less versatile but lower cost options. Can be used by hand or with automatic film applicators. (<a href="https://www.byk.com/" target="_blank">https://www.byk.com</a>)</td>
		</tr>
		<tr>
			<td>Doctor blades, Baker applicators</td>
			<td>Pred Materials</td>
			<td>Baker type applicator and doctor blade. Film casting knives also available.</td>
			<td>Used to cast electrodes films from slurries. Different sizes available, with either metric or English gradations. Bar film or Baker-type applicators and doctor blades are less versatile but lower cost options. Can be used by hand or with automatic film applicators. (<a href="http://www.predmaterials.com/" target="_blank">www.predmaterials.com</a>)</td>
		</tr>
		<tr>
			<td>Automatic film applicator</td>
			<td>BYK Gardner</td>
			<td>2101, 2105, 2121, 2122</td>
			<td>Optional. Used with bar applicators, doctor blades, or film casting knives for automatic electrode film production. Films can also be made by hand but are less uniform. (<a href="https://www.byk.com/" target="_blank">https://www.byk.com</a>)</td>
		</tr>
		<tr>
			<td>Automatic film applicator</td>
			<td>Pred Materials</td>
			<td>Contact vendor</td>
			<td>Optional. Used with bar applicators, doctor blades, or film casting knives for automatic electrode film production. Films can also be made by hand but are less uniform. (<a href="http://www.predmaterials.com/" target="_blank">www.predmaterials.com</a>)</td>
		</tr>
		<tr>
			<td>Potentiostat/Galvanostat</td>
			<td>Bio-Logic Science Instruments</td>
			<td>VSP</td>
			<td>Portable 5 channel computer-controlled potentiostat/galvanostat used to cycle cells for in situ experiments. (<a href="http://www.bio-logic.info/" target="_blank">http://www.bio-logic.info</a>)</td>
		</tr>
		<tr>
			<td>Potentiostat/Galvanostat</td>
			<td>Gamry Instruments</td>
			<td>Reference 3000</td>
			<td>Portable single channel computer-controlled potentiostat/galvanostat used to cycle cells for in situ experiments. (<a href="www.gamry.com" target="_blank">www.gamry.com</a>)</td>
		</tr>
		<tr>
			<td>The Area Diffraction Machine</td>
			<td></td>
			<td>Free download</td>
			<td>Used for analysis of 2D diffraction data. Mac and Windows versions available. <a href="http://code.google.com/p/areadiffractionmachine/" target="_blank">http://code.google.com/p/areadiffractionmachine/</a></td>
		</tr>
		<tr>
			<td>IFEFFIT</td>
			<td></td>
			<td>Free download</td>
			<td>Suite of interactive programs for XAS analysis, including Hephaestus, Athena, and Artemis. Available for Mac, Windows, and UNIX. <a href="http://cars9.uchicago.edu/ifeffit/" target="_blank">http://cars9.uchicago.edu/ifeffit/</a></td>
		</tr>
		<tr>
			<td>SIXPACK</td>
			<td></td>
			<td>Free download</td>
			<td>XAS analysis program that builds on IFEFFIT. Windows and Mac versions. <a href="http://home.comcast.net/~sam_webb/sixpack.html" target="_blank">http://home.comcast.net/~sam_webb/sixpack.html</a></td>
		</tr>
		<tr>
			<td>CelRef</td>
			<td></td>
			<td>Free download</td>
			<td>Graphical unit cell refinement. Windows only. <a href="http://www.ccp14.ac.uk/tutorial/lmgp/celref.htm" target="_blank">http://www.ccp14.ac.uk/tutorial/lmgp/celref.htm and http://www.ccp14.ac.uk/ccp/web-mirrors/lmgp-laugier-bochu/</a></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Reagent/Material</td>
		</tr>
		<tr>
			<td>Electrode active materials</td>
			<td>various</td>
			<td></td>
			<td>Synthesized in-house or obtained from various suppliers.</td>
		</tr>
		<tr>
			<td>Synthetic flake graphite</td>
			<td>Timcal</td>
			<td>SFG-6</td>
			<td>Conductive additive for electrodes. (<a href="http:/www.timcal.com" target="_blank">www.timcal.com</a>)</td>
		</tr>
		<tr>
			<td>Acetylene black</td>
			<td>Denka</td>
			<td>Denka Black</td>
			<td>Conductive additive for electrodes. (<a href="http://www.denka.co.jp/eng/index.html" target="_blank">http://www.denka.co.jp/eng/index.html</a>)</td>
		</tr>
		<tr>
			<td>1-methyl-2-pyrrolidinone (NMP)</td>
			<td>Sigma-Aldrich</td>
			<td>328634</td>
			<td>Used to make electrode slurries. (<a href="http://www.sigmaaldrich.com" target="_blank">www.sigmaaldrich.com</a>)</td>
		</tr>
		<tr>
			<td>Al current collectors</td>
			<td>Exopack</td>
			<td>z-flo 2650</td>
			<td>Carbon-coated foils. Coated on one side. (<a href="http://www.exopackadvancedcoatings.com" target="_blank">http://www.exopackadvancedcoatings.com</a>)</td>
		</tr>
		<tr>
			<td>Al current collectors</td>
			<td>Alfa-Aesar</td>
			<td>10558</td>
			<td>0.025 mm (0.001 in) thick, 30 cm x 30 cm (12 in x 12 in), 99.45% (metals basis), uncoated (<a href="http://www.alfa.com" target="_blank">http://www.alfa.com</a>)</td>
		</tr>
		<tr>
			<td>Cu current collectors</td>
			<td>Pred Materials</td>
			<td>Electrodeposited Cu foil</td>
			<td>For use with anode materials for Li-ion batteries. (<a href="http://www.predmaterials.com" target="_blank">www.predmaterials.com</a>)</td>
		</tr>
		<tr>
			<td>Lithium foil</td>
			<td>Rockwood Lithium</td>
			<td>Contact vendor</td>
			<td>Anode for half cells. Available in different thicknesses and widths. Reactive and air sensitive. Store and handle in an inert atmosphere glovebox under He or Ar (reacts with N2). (<a href="http://www.rockwoodlithium.com" target="_blank">www.rockwoodlithium.com</a>)</td>
		</tr>
		<tr>
			<td>Lithium foil</td>
			<td>Sigma-Aldrich</td>
			<td>320080</td>
			<td>Anode for half cells. Available in different thicknesses and widths. Reactive and air sensitive. Store and handle in an inert atmosphere glovebox under He or Ar (reacts with N2). (<a href="http://www.sigmaaldrich.com" target="_blank">www.sigmaaldrich.com</a>)</td>
		</tr>
		<tr>
			<td>Sodium ingot</td>
			<td>Sigma-Aldrich</td>
			<td>282065</td>
			<td>Anodes for half cells. Can be extruded into foils. Reactive and air sensitive. Store and handle in an inert atmosphere glovebox under He only. (<a href="http://www.sigmaaldrich.com" target="_blank">www.sigmaaldrich.com</a>)</td>
		</tr>
		<tr>
			<td>Electrolyte solutions</td>
			<td>BASF</td>
			<td>Selectilyte P-Series contact vendor</td>
			<td>Contact vendor for desired formulations. (<a href="http://www.catalysts.basf.com/p02/USWeb-Internet/catalysts/en/content/microsites/catalysts/prods-inds/batt-mats/electrolytes" target="_blank">http://www.catalysts.basf.com/p02/USWeb-Internet/catalysts/en/content/microsites/catalysts/prods-inds/batt-mats/electrolytes</a>)</td>
		</tr>
		<tr>
			<td>Dimethyl carbonate (DMC)</td>
			<td>Sigma-Aldrich</td>
			<td>517127</td>
			<td>Used to wash electrodes for ex situ experiments. (<a href="http://www.sigmaaldrich.com" target="_blank">www.sigmaaldrich.com</a>)</td>
		</tr>
		<tr>
			<td>Microporous separators</td>
			<td>Celgard</td>
			<td>2400</td>
			<td>Polypropylene membranes (<a href="http://www.celgard.com/" target="_blank">http://www.celgard.com</a>)</td>
		</tr>
		<tr>
			<td>Coin cell hardware (case, cap, gasket)</td>
			<td>Pred Materials</td>
			<td>CR2016, CR2025, CR2320, CR2032</td>
			<td>Match size to available crimping tool, Al-clad components also available. (<a href="http://www.predmaterials.com" target="_blank">www.predmaterials.com</a>)</td>
		</tr>
		<tr>
			<td>Wave washers</td>
			<td>Pred Materials</td>
			<td>SUS316L</td>
			<td>(<a href="http://www.predmaterials.com/" target="_blank">www.predmaterials.com</a>)</td>
		</tr>
		<tr>
			<td>Spacers</td>
			<td>Pred Materials</td>
			<td>SUS316L</td>
			<td>(<a href="http://www.predmaterials.com/" target="_blank">www.predmaterials.com</a>)</td>
		</tr>
		<tr>
			<td>Ni and Al pretaped tabs</td>
			<td>Pred Materials</td>
			<td>Contact vendor</td>
			<td>Sizes subject to change. Inquire about custom orders. (<a href="http://www.predmaterials.com/" target="_blank">www.predmaterials.com</a>)</td>
		</tr>
		<tr>
			<td>Polyester pouches</td>
			<td>VWR</td>
			<td>11214-301</td>
			<td>Used to seal electrochemical cells for in situ work. Avoid heavy duty pouches because of strong signal interference. (<a href="https://us.vwr.com" target="_blank">https://us.vwr.com</a>)</td>
		</tr>
		<tr>
			<td>Kapton film</td>
			<td>McMaster-Carr</td>
			<td>7648A735</td>
			<td>Used to cover electrodes for ex situ experiments, 0.0025 in thick (<a href="http://www.mcmaster.com/" target="_blank">www.mcmaster.com</a>)</td>
		</tr>
		<tr>
			<td>Helium, Argon and 4-10% hydrogen in helium or argon</td>
			<td>Air Products</td>
			<td>contact vendor for desired compositions and purity levels</td>
			<td>Helium or argon used to fill glovebox where cell assembly is carried out and alkali metal is stored. (<a href="http://www.airproducts.com/products/gases.aspx" target="_blank">http://www.airproducts.com/products/gases.aspx</a>)</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Do not use nitrogen because it reacts with lithium. Use only helium if sodium is being stored. 
			Purity level needed depends on whether the glovebox is equipped with a water and oxygen removal system. Hydrogen mixtures needed to regenerate water/oxygen removal system, if present&#160;or any other suitable gas supplier</td>
		</tr>
	</tbody>
</table>

characterization of electrode materials for lithium ion and sodium ion batteries using synchrotron radiation techniques

Intercalation compounds such as transition metal oxides or phosphates are the most commonly used electrode materials in Li-ion and Na-ion batteries. During insertion or removal of alkali metal ions, the redox states of transition metals in the compounds change and structural transformations such as phase transitions and/or lattice parameter increases or decreases occur. These behaviors in turn determine important characteristics of the batteries such as the potential profiles, rate capabilities, and cycle lives. The extremely bright and tunable x-rays produced by synchrotron radiation allow rapid acquisition of high-resolution data that provide information about these processes. Transformations in the bulk materials, such as phase transitions, can be directly observed using X-ray diffraction (XRD), while X-ray absorption spectroscopy (XAS) gives information about the local electronic and geometric structures (e.g.&#160;changes in redox states and bond lengths). In situ experiments carried out on operating cells are particularly useful because they allow direct correlation between the electrochemical and structural properties of the materials. These experiments are time-consuming and can be challenging to design due to the reactivity and air-sensitivity of the alkali metal anodes used in the half-cell configurations, and/or the possibility of signal interference from other cell components and hardware. For these reasons, it is appropriate to carry out ex situ experiments (e.g.&#160;on electrodes harvested from partially charged or cycled cells) in some cases. Here, we present detailed protocols for the preparation of both ex situ and in situ samples for experiments involving synchrotron radiation and demonstrate how these experiments are done.

Figure 2 shows a typical sequence used for an in situ experiment. After synthesis and characterization of active material powders, composite electrodes are prepared from slurries containing the active material, a binder such as polyvinylidene fluoride (PVDF) and conductive additives such as carbon black or graphite suspended in N-methylpyrrolidinone (NMP), cast onto either aluminum or copper foil current collectors. Aluminum is used for lithium ion battery cathodes and all sodium ion battery ele...

Watch this Scientific Journal Video about Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques at JoVE.com

Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques

We describe the use of synchrotron X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) techniques to probe details of intercalation/deintercalation processes in electrode materials for Li-ion and Na-ion batteries. Both in situ and ex situ experiments are used to understand structural behavior relevant to the operation of devices

Intercalation compounds such as transition metal oxides or phosphates are the most commonly used electrode materials in Li-ion and Na-ion batteries. ...

characterization-electrode-materials-for-lithium-ion-sodium-ion

Research

JoVE Journal

Engineering

Construction and Testing of Coin Cells of Lithium Ion Batteries

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime. Lithium ion batteries have also been considered to be used in electric and hybrid vehicles1 or even electrical grid stabilization systems2. All these applications simulate a dramatic increase in the research and development of battery materials3-7, including new materials3,8, doping9, nanostructuring10-13, coatings or surface modifications14-17 and novel binders18. Consequently, an increasing number of physicists, chemists and materials scientists have recently ventured into this area. Coin cells are widely used in research laboratories to test new battery materials; even for the research and development that target large-scale and high-power applications, small coin cells are often used to test the capacities and rate capabilities of new materials in the initial stage. 
 In 2010, we started a National Science Foundation (NSF) sponsored research project to investigate the surface adsorption and disordering in battery materials (grant no. DMR-1006515). In the initial stage of this project, we have struggled to learn the techniques of assembling and testing coin cells, which cannot be achieved without numerous help of other researchers in other universities (through frequent calls, email exchanges and two site visits). Thus, we feel that it is beneficial to document, by both text and video, a protocol of assembling and testing a coin cell, which will help other new researchers in this field. This effort represents the "Broader Impact" activities of our NSF project, and it will also help to educate and inspire students.
In this video article, we document a protocol to assemble a CR2032 coin cell with a LiCoO2 working electrode, a Li counter electrode, and (the mostly commonly used) polyvinylidene fluoride (PVDF) binder. To ensure new learners to readily repeat the protocol, we keep the protocol as specific and explicit as we can. However, it is important to note that in specific research and development work, many parameters adopted here can be varied. First, one can make coin cells of different sizes and test the working electrode against a counter electrode other than Li. Second, the amounts of C black and binder added into the working electrodes are often varied to suit the particular purpose of research; for example, large amounts of C black or even inert powder were added to the working electrode to test the "intrinsic" performance of cathode materials14. Third, better binders (other than PVDF) have also developed and used18. Finally, other types of electrolytes (instead of LiPF6) can also be used; in fact, certain high-voltage electrode materials will require the uses of special electrolytes7.

A protocol to construct and test coin cells of lithium ion batteries is described. The specific procedures of making a working electrode, preparing a counter electrode, assembling a cell inside a glovebox and testing the cell are presented.

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime.  Lithium ion ...

Solid-state Graft Copolymer Electrolytes for Lithium Battery Applications

Battery safety has been a very important research area over the past decade. Commercially available lithium ion batteries employ low flash point (&lt;80 &deg;C), flammable, and volatile organic electrolytes. These organic based electrolyte systems are viable at ambient temperatures, but require a cooling system to ensure that temperatures do not exceed 80 &deg;C. These cooling systems tend to increase battery costs and can malfunction which can lead to battery malfunction and explosions, thus endangering human life. Increases in petroleum prices lead to a huge demand for safe, electric hybrid vehicles that are more economically viable to operate as oil prices continue to rise. Existing organic based electrolytes used in lithium ion batteries are not applicable to high temperature automotive applications. A safer alternative to organic electrolytes is solid polymer electrolytes. This work will highlight the synthesis for a graft copolymer electrolyte (GCE) poly(oxyethylene) methacrylate (POEM) to a block with a lower glass transition temperature (Tg) poly(oxyethylene) acrylate (POEA). The conduction mechanism has been discussed and it has been demonstrated the relationship between polymer segmental motion and ionic conductivity indeed has a Vogel-Tammann-Fulcher (VTF) dependence. Batteries containing commercially available LP30 organic (LiPF6 in ethylene carbonate (EC):dimethyl carbonate (DMC) at a 1:1 ratio) and GCE were cycled at ambient temperature. It was found that at ambient temperature, the batteries containing GCE showed a greater overpotential when compared to LP30 electrolyte. However at temperatures greater than 60 &deg;C, the GCE cell exhibited much lower overpotential due to fast polymer electrolyte conductivity and nearly the full theoretical specific capacity of 170 mAh/g was accessed.

Lithium ion batteries employ flammable and volatile organic electrolytes that are suitable for ambient temperature applications. A safer alternative to organic electrolytes are solid polymer batteries. Solid polymer batteries operate safely at high temperatures (&gt;120 &deg;C), thus making them applicable to high temperature applications such as deep oil drilling and hybrid electric vehicles. This paper will discuss (a) the polymer synthesis, (b) the polymer conduction mechanism, and (c) provide temperature cycling for both solid polymer and organic electrolytes.

Battery safety has been a very important research area over the past decade. Commercially available lithium ion batteries employ low flash point (&lt;80 ...

Characterization of Surface Modifications by White Light Interferometry: Applications in Ion Sputtering, Laser Ablation, and Tribology Experiments

In materials science and engineering it is often necessary to obtain quantitative measurements of surface topography with micrometer lateral resolution. From the measured surface, 3D topographic maps can be subsequently analyzed using a variety of software packages to extract the information that is needed.
In this article we describe how white light interferometry, and optical profilometry (OP) in general, combined with generic surface analysis software, can be used for materials science and engineering tasks. In this article, a number of applications of white light interferometry for investigation of surface modifications in mass spectrometry, and wear phenomena in tribology and lubrication are demonstrated. We characterize the products of the interaction of semiconductors and metals with energetic ions (sputtering), and laser irradiation (ablation), as well as ex situ measurements of wear of tribological test specimens.
Specifically, we will discuss:
<ol class="lroman">
	<li>Aspects of traditional ion sputtering-based mass spectrometry such as sputtering rates/yields measurements on Si and Cu and subsequent time-to-depth conversion.</li>
	<li>Results of quantitative characterization of the interaction of femtosecond laser irradiation with a semiconductor surface. These results are important for applications such as ablation mass spectrometry, where the quantities of evaporated material can be studied and controlled via pulse duration and energy per pulse. Thus, by determining the crater geometry one can define depth and lateral resolution versus experimental setup conditions.</li>
	<li>Measurements of surface roughness parameters in two dimensions, and quantitative measurements of the surface wear that occur as a result of friction and wear tests.</li>
</ol>
Some inherent drawbacks, possible artifacts, and uncertainty assessments of the white light interferometry approach will be discussed and explained.

White light microscope interferometry is an optical, noncontact and quick method for measuring the topography of surfaces. It is shown how the method can be applied toward mechanical wear analysis, where wear scars on tribological test samples are analyzed; and in materials science to determine ion beam sputtering or laser ablation volumes and depths.

In materials science and engineering it is often necessary to obtain quantitative measurements of surface topography with micrometer lateral resolution. ...

In Situ Neutron Powder Diffraction Using Custom-made Lithium-ion Batteries

Li-ion batteries are widely used in portable electronic devices and are considered as promising candidates for higher-energy applications such as electric vehicles.1,2 However, many challenges, such as energy density and battery lifetimes, need to be overcome before this particular battery technology can be widely implemented in such applications.3 This research is challenging, and we outline a method to address these challenges using in situ NPD to probe the crystal structure of electrodes undergoing electrochemical cycling (charge/discharge) in a battery. NPD data help determine the underlying structural mechanism responsible for a range of electrode properties, and this information can direct the development of better electrodes and batteries.
We briefly review six types of battery designs custom-made for NPD experiments and detail the method to construct the &#8216;roll-over&#8217; cell that we have successfully used on the high-intensity NPD instrument, WOMBAT, at the Australian Nuclear Science and Technology Organisation (ANSTO). The design considerations and materials used for cell construction are discussed in conjunction with aspects of the actual in situ NPD experiment and initial directions are presented on how to analyze such complex in situ data.

In Situ Neutron Powder Diffraction Using Custom-made Lithium-ion Batteries

We describe the design and construction of an electrochemical cell for the examination of electrode materials using in situ neutron powder diffraction (NPD). We briefly comment on alternate in situ NPD cell designs and discuss methods for the analysis of the corresponding in situ NPD data produced using this cell.

Li-ion batteries are widely used in portable electronic devices and are considered as promising candidates for higher-energy applications such as electric ...

Failure Analysis of Batteries Using Synchrotron-based Hard X-ray Microtomography

Imaging morphological changes that occur during the lifetime of rechargeable batteries is necessary to understand how these devices fail. Since the advent of lithium-ion batteries, researchers have known that the lithium metal anode has the highest theoretical energy density of any anode material. However, rechargeable batteries containing a lithium metal anode are not widely used in consumer products because the growth of lithium dendrites from the anode upon charging of the battery causes premature cell failure by short circuit. Lithium dendrites can also form in commercial lithium-ion batteries with graphite anodes if they are improperly charged. We demonstrate that lithium dendrite growth can be studied using synchrotron-based hard X-ray microtomography. This non-destructive imaging technique allows researchers to study the growth of lithium dendrites, in addition to other morphological changes inside batteries, and subsequently develop methods to extend battery life.

Synchrotron-based hard X-ray microtomography is used to image the electrochemical growth of dendrites from a lithium metal electrode through a solid polymer electrolyte membrane.

Imaging morphological changes that occur during the lifetime of rechargeable batteries is necessary to understand how these devices fail. Since the advent ...

Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films

The biological uptake of plutonium (Pu) in aquatic ecosystems is of particular concern since it is an alpha-particle emitter with long half-life which can potentially contribute to the exposure of biota and humans. The diffusive gradients in thin films technique is introduced here for in-situ measurements of Pu bioavailability and speciation. A diffusion cell constructed for laboratory experiments with Pu and the newly developed protocol make it possible to simulate the environmental behavior of Pu in model solutions of various chemical compositions. Adjustment of the oxidation states to Pu(IV) and Pu(V) described in this protocol is essential in order to investigate the complex redox chemistry of plutonium in the environment. The calibration of this technique and the results obtained in the laboratory experiments enable to develop a specific DGT device for in-situ Pu measurements in freshwaters. Accelerator-based mass-spectrometry measurements of Pu accumulated by DGTs in a karst spring allowed determining the bioavailability of Pu in a mineral freshwater environment. Application of this protocol for Pu measurements using DGT devices has a large potential to improve our understanding of the speciation and the biological transfer of Pu in aquatic ecosystems.

The technique of diffusive gradients in thin films (DGT) is proposed for speciation studies of plutonium. This protocol describes diffusion experiments probing the behavior of Pu(IV) and Pu(V) in presence of organic matter. DGTs deployed in a karstic spring allow assessment of the bioavailability of Pu.

The biological uptake of plutonium (Pu) in aquatic ecosystems is of particular concern since it is an alpha-particle emitter with long half-life which can ...

Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures

Layer semiconductors with easily processed two-dimensional (2D) structures exhibit indirect-to-direct bandgap transitions and superior transistor performance, which suggest a new direction for the development of next-generation ultrathin and flexible photonic and electronic devices. Enhanced luminescence quantum efficiency has been widely observed in these atomically thin 2D crystals. However, dimension effects beyond quantum confinement thicknesses or even at the micrometer scale are not expected and have rarely been observed. In this study, molybdenum diselenide (MoSe2) layer crystals with a thickness range of 6-2,700 nm were fabricated as two- or four-terminal devices. Ohmic contact formation was successfully achieved by the focused-ion beam (FIB) deposition method using platinum (Pt) as a contact metal. Layer crystals with various thicknesses were prepared through simple mechanical exfoliation by using dicing tape. Current-voltage curve measurements were performed to determine the conductivity value of the layer nanocrystals. In addition, high-resolution transmission electron microscopy, selected-area electron diffractometry, and energy-dispersive X-ray spectroscopy were used to characterize the interface of the metal&#8211;semiconductor contact of the FIB-fabricated MoSe2 devices. After applying the approaches, the substantial thickness-dependent electrical conductivity in a wide thickness range for the MoSe2-layer semiconductor was observed. The conductivity increased by over two orders of magnitude from 4.6 to 1,500 &#937;&#8722;1 cm&#8722;1, with a decrease in the thickness from 2,700 to 6 nm. In addition, the temperature-dependent conductivity indicated that the thin MoSe2 multilayers exhibited considerably weak semiconducting behavior with activation energies of 3.5-8.5 meV, which are considerably smaller than those (36-38 meV) of the bulk. Probable surface-dominant transport properties and the presence of a high surface electron concentration in MoSe2 are proposed. Similar results can be obtained for other layer semiconductor materials such as MoS2 and WS2.

We describe the approaches for the device fabrication and electrical characterization of molybdenum diselenide (MoSe2) layer semiconductor nanostructures with different thicknesses. In addition, the fabrication of ohmic contacts for MoSe2-layer nanocrystals by the focused-ion beam deposition method using platinum (Pt) as a contact metal is described.

Layer semiconductors with easily processed two-dimensional (2D) structures exhibit indirect-to-direct bandgap transitions and superior transistor ...

Non-aqueous Electrode Processing and Construction of Lithium-ion Coin Cells

Research into new and improved materials to be utilized in lithium-ion batteries (LIB) necessitates an experimental counterpart to any computational analysis. Testing of lithium-ion batteries in an academic setting has taken on several forms, but at the most basic level lies the coin cell construction. In traditional LIB electrode preparation, a multi-phase slurry composed of active material, binder, and conductive additive is cast out onto a substrate. An electrode disc can then be punched from the dried sheet and used in the construction of a coin cell for electrochemical evaluation. Utilization of the potential of the active material in a battery is critically dependent on the microstructure of the electrode, as an appropriate distribution of the primary components are crucial to ensuring optimal electrical conductivity, porosity, and tortuosity, such that electrochemical and transport interaction is optimized. Processing steps ranging from the combination of dry powder, wet mixing, and drying can all critically affect multi-phase interactions that influence the microstructure formation. Electrochemical probing necessitates the construction of electrodes and coin cells with the utmost care and precision. This paper aims at providing a step-by-step guide of non-aqueous electrode processing and coin cell construction for lithium-ion batteries within an academic setting and with emphasis on deciphering the influence of drying and calendaring.

Non-aqueous electrode processing is central to the construction of coin cells and the evaluation of new electrode chemistries for lithium-ion batteries. A step-by-step guide to the basic practices needed as an electrochemical engineer working with batteries in an academic experimental setting is furnished.

Research into new and improved materials to be utilized in lithium-ion batteries (LIB) necessitates an experimental counterpart to any computational ...

Using Synchrotron Radiation Microtomography to Investigate Multi-scale Three-dimensional Microelectronic Packages

Synchrotron radiation micro-tomography (SR&#181;T) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data acquisition times with high spatial resolution. In the electronics industry there is serious interest in performing failure analysis on 3D microelectronic packages, many which contain multiple levels of high-density interconnections. Often in tomography there is a trade-off between image resolution and the volume of a sample that can be imaged. This inverse relationship limits the usefulness of conventional computed tomography (CT) systems since a microelectronic package is often large in cross sectional area 100-3,600 mm2, but has important features on the micron scale. The micro-tomography beamline at the Advanced Light Source (ALS), in Berkeley, CA USA, has a setup which is adaptable and can be tailored to a sample&#39;s properties, i.e., density, thickness, etc., with a maximum allowable cross-section of 36 x 36 mm. This setup also has the option of being either monochromatic in the energy range ~7-43 keV or operating with maximum flux in white light mode using a polychromatic beam. Presented here are details of the experimental steps taken to image an entire 16 x 16 mm system within a package, in order to obtain 3D images of the system with a spatial resolution of 8.7 &#181;m all within a scan time of less than 3 min. Also shown are results from packages scanned in different orientations and a sectioned package for higher resolution imaging. In contrast a conventional CT system would take hours to record data with potentially poorer resolution. Indeed, the ratio of field-of-view to throughput time is much higher when using the synchrotron radiation tomography setup. The description below of the experimental setup can be implemented and adapted for use with many other multi-materials.

For this study synchrotron radiation micro-tomography, a non-destructive three-dimensional imaging technique, is employed to investigate an entire microelectronic package with a cross-sectional area of 16 x 16 mm. Due to the synchrotron&#39;s high flux and brightness the sample was imaged in just 3 min&#160;with an 8.7 &#181;m spatial resolution.

Synchrotron radiation micro-tomography (SR&#181;T) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data ...

Synthesis of Ionic Liquid Based Electrolytes, Assembly of Li-ion Batteries, and Measurements of Performance at High Temperature

The chemical instability of the traditional electrolyte remains a safety issue in widely used energy storage devices such as Li-ion batteries. Li-ion batteries for use in devices operating at elevated temperatures require thermally stable and non-flammable electrolytes. Ionic liquids (ILs), which are non-flammable, non-volatile, thermally stable molten salts, are an ideal replacement for flammable and low boiling point organic solvent electrolytes currently used today. We herein describe the procedures to: 1) synthesize mono- and di-phosphonium ionic liquids paired with chloride or bis(trifluoromethane)sulfonimide (TFSI) anions; 2) measure the thermal properties and stability of these ionic liquids by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA); 3) measure the electrochemical properties of the ionic liquids by cyclic voltammetry (CV); 4) prepare electrolytes containing lithium bis(trifluoromethane)sulfonamide; 5) measure the conductivity of the electrolytes as a function of temperature; 6) assemble a coin cell battery with two of the electrolytes along with a Li metal anode and LiCoO2 cathode; and 7) evaluate battery performance at 100 &#176;C. We additionally describe the challenges in execution as well as the insights gained from performing these experiments.

Here, we describe protocols to prepare phosphonium-based ionic liquid and lithium bis(trifluoromethane)sulfonimide salt electrolytes, and assemble a non-flammable and high temperature functioning lithium-ion coin cell battery.

The chemical instability of the traditional electrolyte remains a safety issue in widely used energy storage devices such as Li-ion batteries. Li-ion ...