Primary funding for the work was provided by the Electron Microscopy of Soft Matter Program from the Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The battery assembly portion of the project was supported by the BATT program from the Vehicle Technologies program, through the Office of Energy Efficiency and Renewable Energy under U.S. DOE Contract DE-AC02-05CH11231. Hard X-ray microtomography experiments were performed at the Advanced Light Source which is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Katherine J. Harry was supported by a National Science Foundation Graduate Research Fellowship.

1. Elektrolyt Herstellung <ol><li> Synthetisieren eine 240 kg / mol - 260 kg / mol Poly (styrol) - blockieren - Poly (ethylenoxid) Copolymer (SEO) mit anionische Polymerisation. <ol><li> Führen Sie alle zusätzliche Probenvorbereitung in einer Argon-Handschuhfach, wo die Wasser- und Sauerstoffgehalt kontrolliert werden und zu bleiben &lt;5 ppm. </li><li> Aufzulösen 0,3 g Polymer in wasserfreiem N-Methyl-2-pyrrolidon (NMP) mit trockenem Lithiumbis (Trifluormethan) Sulfonimid (LiTFSI) Salz. Verwenden Sie einen LiTFSI Salz SEO Massenverhältnis von 0,275 und einer NMP-Masse-Verhältnis von 13,13 SEO. Hinweis: Diese Polymermenge wird eine Membran groß genug, um etwa 20 Proben machen ergeben. </li><li> Guss gesamte Polymer und Salz-Gemisch in den Schritten hergestellt oben auf eine ca. 15 cm x 15 cm großes quadratisches Stück aus Nickelfolie unter Verwendung einer Rakel. Trocknen des resultierenden Films bei 60 ° CO / N. </li><li> Nach dem Trocknen schälen die Folie von der Nickelfolie und erlauben weiter unter Vakuum bei 9 trocknen0 ° C. </li><li> Wickeln Sie die resultierende freistehenden Films in Nickelfolie und Speicherung innerhalb einer luftdichten Box im Handschuhfach für den späteren Gebrauch. </li></ol></li></ol> 2. Lithium - Lithium Symmetric Zellpräparation <ol><li> Verwenden Sie einen 7/16 im Durchmesser, runde Metall Punch, um von einer Rolle von 99,9% rein, Batterie-Grade-Lithiummetallfolie ausgeschnitten zwei Lithium-Metall-Elektroden. </li><li> Verwenden Sie einen 1/2 Zoll Durchmesser Metall Punch zu schneiden Sie ein Stück des Polymerelektrolyt-Film. Hinweis: Das Lithiummetall ist weicher und leichter zu stanzen als der Polymerelektrolyt. </li><li> Sandwich der Polymerelektrolytfilm zwischen den beiden Lithium-Metall-Elektroden und drücken Sie die Nickel-Registerkarten auf die Elektroden. </li><li> Vakuumdichtung der Probe in einem luftdichten Beutel aus Polypropylen und Nylon gefüttert Aluminium. Hinweis: Eine der Lithium-Elektroden ist leicht mit einer Kathode vertauscht, wenn man eine volle Batterie studieren will. </li></ol> 3. Symmetrische Handy Cyclin<html> g <ol><li> Legen Sie die vakuumdichte Probe in einem Ofen bei 90 ° C und Zyklus mit elektrochemischen Fahrradausrüstung statt. Erhitzen Sie die Probe während dem Fahrrad zur angemessenen Ionenleitfähigkeit durch die Elektrolytmembran zu erreichen. Zur Sicherheit, dass die Probe nicht die Lithiummetallschmelzpunkt von 180 ° C nähern. </li><li> Übergeben Sie eine Stromdichte von 0,175 mA / cm 2 durch die Probe 4 Stunden lang und folgen Sie mit einer 45 min Pause. Als nächstes passieren eine Stromdichte von -0,175 mA / cm 2 durch die Probe 4 Stunden lang und folgen Sie mit einer 45 min Pause. Wiederholen Sie diesen Radfahren Routine so oft wie gewünscht. </li><li> Beachten Sie die Spannungsantwort für diese Stromdichte durch eine 30 um dicke SEO Elektrolyten geleitet und vergleichen Sie mit dem in Abbildung 1 dargestellt. Stoppen Sie den Radsport-Routine, wenn die Zellenspannung als Reaktion sinkt auf 0,00 V, weil die Batterie durch Kurzschluss anzeigt, der ausgefallene Wachstum von Lithiumdendriten. </li></ol>itel &quot;&gt; 4. Synchrotron harter Röntgenmikrotomographie Imaging <ol><li> Nachdem der symmetrischen Zelle getaktet, bringen sie zurück in das Handschuhfach und entfernen Sie sie aus seinem Beutel. </li><li> Verwenden Sie einen 1/8 Zoll Metallstempel zum Ausschneiden der Mittelteil des cell.Vacuum dichten den Mittelabschnitt der Zelle in Beutelmaterial und aus dem Handschuhfach entfernen, für den Transport zum Synchrotron. Hinweis: In der Abbildung einer Probe mit einem reduzierten Durchmesser, wird die Menge an Material außerhalb des Sichtfeldes des Röntgendetektors verringert. Dies verbessert die Bildqualität insgesamt durch die Reduzierung von Lärm durch dieses Zusatzmaterial verursacht. Darüber hinaus ist die Entfernung der hoch röntgenstrahlenabsorbierenden Nickel Stromkollektoren notwendig, für diese Taschenkonstruktion, klare Röntgenbilder zu erhalten. </li><li> Einmal an der Strahllinie verwenden Polyimidband um die Probe auf dem Probentisch zu befestigen. Falls erwünscht, das Band um kleine Metallmarker auf der Oberseite der Probe mit Ausrichtung zu unterstützen. Legen Sie die Metall-Marker etwa in der Mitte des sample, um den Ort, um die die Probe einmal ausgerichtet drehen markieren. </li><li> Verwenden Sie 20 keV Röntgenstrahlen, die dem Bild der Probe mit einer Belichtungszeit für das System optimiert. Optimieren Sie die Belichtungszeit durch den Ausgleich des Scanzeit und die Anzahl der Zählungen pro Bild. Schätzung der Gesamtscanzeit durch Multiplizieren der Belichtungszeit durch die Anzahl der gesammelten Bilder. <ol><li> Hierbei kann die Verwendung einer Belichtungszeit von 300 msec, was eine Zykluszeit von 5 bis 10 min. </li></ol></li><li> Messen der Pixelgröße, wobei die optischen Linsen an der Beginn jeder Messzeit Verschiebung verbunden. Anmerkung: Für den 4x-Objektiv verwendet, um das in 2 gezeigte Bild zu nehmen, die Pixelgröße betrug 1,61 &amp; mgr; m / Pixel. Höheren Vergrößerungslinsen (10x und 20x) sind auch für die Nutzung zur Verfügung. </li><li> Position und Ausrichtung der Probe auf einem Drehtisch in Bezug auf das Detektionssystem, so daß sie in das Sichtfeld des Detektors bleibt, wie es durch 180 ° dreht. </li><li> Positionieren Sie die Probe so nahder Detektor wie möglich gleichzeitig sicherzustellen, dass die Probe nicht den Detektor treffen jederDrehWinkel. Hinweis: Da die Probe in zunehmendem Abstand Detektor wird der Fresnel-Phasenkontrast stärker ausgeprägt in den rekonstruierten Bildern geworden. Dies kann Features zu verschleiern und zu einer schlechteren Auflösung. Beutel für Zellen ist die Probe zum Detektor-Abstand typischerweise in der Größenordnung von 3 cm von dem Detektor weg. </li><li> Sobald sie ausgerichtet, einen Scanvorgang, bestehend aus 1.025 Bildern über Muster Drehungen zwischen 0 und 180 ° gesammelt. &quot;Hellfeld&quot; Sammeln Sie Bilder durch Bewegen der Probe aus dem Sichtfeld (auch als &quot;Flachfeld&quot; oder &quot;Hintergrund&quot; bekannt). Zusätzlich sammeln &quot;Dunkelfeld&quot; Bilder, indem sie Bilder, während der Strahl ausgeschaltet ist. Verwenden Sie diese, um die Beispielbilder für inhomogene Beleuchtung, Szintillator Antwort und CCD-Kamera als Reaktion zu normalisieren. </li></ol> 5. Bildrekonstruktion <ol><li> Tomographischrekonstruieren den Satz von 1025 Röntgenaufnahmen in einen Stapel von Bildern, wobei jedes Bild stellt eine Scheibe in dem Volumen nach dem folgenden Verfahren. <ol><li> Erstens, normalisieren die Bilder durch Subtraktion der &quot;Dunkelfeld&quot; Bilder von den beiden Röntgenbildern und den &quot;Hellfeld&quot; Bilder. Teilen Sie die resultierende Röntgenbilder geteilt durch den resultierenden &quot;Hellfeld&quot; Bilder. </li><li> Als nächstes führen tomographischen Rekonstruktion, das Verfahren, durch das die Reihe von Projektionswinkeln in ein 3D-Bild umgewandelt, von dem normierten Röntgenbildern nach dem Protokoll des Herstellers. Hinweis: Der Rekonstruktionssoftware gibt eine Reihe von Bildern, die jeweils einen horizontalen Schnitt durch die gestapelten sample.When dieser Satz von rekonstruierten Bilder bilden eine dreidimensionale Röntgenabsorptions Karte der Probe. </li></ol></li><li> Visualisierung der einzelnen Scheiben bzw. der Probe in drei Dimensionen zu sehen, was die Probe aussieht auf der Innenseite.</li></ol> 6. Daten-Visualisierung und Verarbeitung <ol><li> Verwenden Sie eine aus einer Vielzahl von kommerziellen und Open-Source-Bildbearbeitungs-Software-Pakete für Datenvisualisierung und Analyse zur Verfügung. 22, 23 </li><li> Beim Öffnen der Stapel von rekonstruierten Bildern mit der gewünschten Software zu erstellen orthoslices, um die XY, XZ und YZ Perspektiven der rekonstruierten Daten zeigen. </li><li> Die Kamera schwenkt durch diese Bilder und die Suche nach Eigenschaften von Interesse, wie die in 2 gezeigte Lithiumdendrit. </li><li> Als Nächstes verwenden Segmentierung (digital Kennzeichnung) und 3D-Rendering-Werkzeuge, um das Merkmal von Interesse in drei Dimensionen zu machen. </li><li> Digital-Segment das Bild, erstellen Sie ein Beschriftungsfeld und benutzen Schwellen Tools, um Bereiche der Probe, die einem Material zu wählen. </li><li> Um ein Bild wie das in 2B gezeigt neu zu erstellen, beschriften Sie die dunklen Pixel Lithium und den hellen Pixeln Elektrolyten. Beschriften Sie die in das enthaltene Lithium-Dendriten getrennt von den oberen und unteren Lithiumelektroden. <ol><li> Rendern Sie die dendritischen Lithium in Orange und die Polymer-Elektrolyt in blau. Rendern der oberen und unteren Lithiummetallelektroden in grau und stellen Sie den Transparenzwert um den orangefarbenen dendritischen Lithium offenbaren. Drehen dieses dreidimensionalen Rekonstruktion, die Struktur aus vielen Perspektiven zu betrachten. </li></ol></li></ol>

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E., Doyle, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Capacity+fade+mechanisms+and+side+reactions+in+lithium-ion+batteries.">Capacity fade mechanisms and side reactions in lithium-ion batteries.</a> J Electrochem Soc. 145, 3647-3667 (1998).</li><li>Ebner, M., Marone, F., Stampanoni, M., Wood, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visualization+and+Quantification+of+Electrochemical+and+Mechanical+Degradation+in+Li+Ion+Batteries.">Visualization and Quantification of Electrochemical and Mechanical Degradation in Li Ion Batteries.</a> Science. 342, 716-720 (2013).</li><li>Qi, Y., Harris, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+Situ+Observation+of+Strains+during+Lithiation+of+a+Graphite+Electrode.">In Situ Observation of Strains during Lithiation of a Graphite Electrode.</a> J Electrochem Soc. 157, A741-A747 (2010).</li><li>Eastwood, D. S., 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=Three-dimensional+characterization+of+electrodeposited+lithium+microstructures+using+synchrotron+X-ray+phase+contrast+imaging.">Three-dimensional characterization of electrodeposited lithium microstructures using synchrotron X-ray phase contrast imaging.</a> Chem Commun. , (2014).</li><li>Shui, J. -. L., 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=Reversibility+of+anodic+lithium+in+rechargeable+lithium&#8211;oxygen+batteries.">Reversibility of anodic lithium in rechargeable lithium&#8211;oxygen batteries.</a> Nat commun. 4, (2013).</li><li>Harry, K. J., Hallinan, D. T., Parkinson, D. Y., MacDowell, A. A., Balsara, N. 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L. <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+X-ray+Microtomography.">Three-Dimensional X-ray Microtomography.</a> Science. 237, 1439-1444 (1987).</li><li>Singh, M., 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=Effect+of+molecular+weight+on+the+mechanical+and+electrical+properties+of+block+copolymer+electrolytes.">Effect of molecular weight on the mechanical and electrical properties of block copolymer electrolytes.</a> Macromolecules. 40, 4578-4585 (2007).</li><li>Monroe, C., Newman, 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+Impact+of+Elastic+Deformation+on+Deposition+Kinetics+at+Lithium/Polymer+Interfaces.">The Impact of Elastic Deformation on Deposition Kinetics at Lithium/Polymer Interfaces.</a> J Electrochem Soc. 152, A396-1149 (2005).</li><li>Stone, G. M., 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=Resolution+of+the+Modulus+versus+Adhesion+Dilemma+in+Solid+Polymer+Electrolytes+for+Rechargeable+Lithium+Metal+Batteries.">Resolution of the Modulus versus Adhesion Dilemma in Solid Polymer Electrolytes for Rechargeable Lithium Metal Batteries.</a> J Electrochem Soc. 159, A222-A227 (2012).</li><li>Panday, A., 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=Effect+of+Molecular+Weight+and+Salt+Concentration+on+Conductivity+of+Block+Copolymer+Electrolytes.">Effect of Molecular Weight and Salt Concentration on Conductivity of Block Copolymer Electrolytes.</a> Macromolecules. 42, 4632-4637 (2009).</li><li>Schneider, C. A., Rasband, W. S., Eliceiri, K. 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The authors have nothing to disclose.

Harten Röntgenmikrotomographie ist besonders gut geeignet für die luftempfindlichen Proben, wie viele elektrochemisch aktiven Materialien, da die Röntgenstrahlen durch Schutztasche Material eindringen, so dass einfache Abbildung der Probe ohne Kontakt mit Luft. Vielleicht die wertvolle Eigenschaft dieser Abbildungstechnik ist, dass die eindringenden Röntgenstrahlen dem Benutzer erlauben, im Inneren der Probe ohne Zerstörung sehen. Häufigste bildgebenden Verfahren wie Rasterelektronenmikroskopie und traditionelle o...

Researchers are actively investigating battery chemistries with theoretical energy densities over an order of magnitude larger than traditional lithium-ion batteries.1,2 These high-energy-density batteries will make electric vehicles more competitive with their gasoline-powered counterparts.3 However, these new chemistries have several failure modes that preclude their use in commercial technologies. For example, these battery chemistries require a lithium metal anode to achieve large enhancements in energy density; unfortunately, lithium metal is prone to dendrite growth as lithium ions are reduced at the anode surface during charging.4-9 Additionally, breakage of active particles in the cathode and poor adhesion within the battery can cause cell failure.10
Many modes of battery failure occur on the micrometer scale. However, most battery materials are air sensitive making sample preparation for analysis by electron microscopy and traditional optical microscopy difficult. Synchrotron hard X-ray microtomography allows one to visualize the interior of a battery without disassembly.11-14 Furthermore, the technique produces a three-dimensional (3D) reconstruction of the assembled cell making it easy to find locations of failure.15 Finding robust techniques that enable researchers to develop the scientific understanding required to accurately predict the lifetime of a battery is critical for the design of next generation battery technologies. The procedure discussed herein will specifically demonstrate how one can prepare and image model batteries to study the growth of lithium metal dendrites through solid polymer electrolyte membranes.
Computed tomography (CT) scanning is not a new technique and has been used frequently for failure analysis in industry. Synchrotron-based X-ray microtomography is advantageous because the high brightness and flux of the source allow collection of images with high resolution and good signal to noise in a much shorter amount of time.16 Additionally, one can take advantage of the X-ray energy resolution to image at energies around a chemical species&#8217; absorption edge, causing the components containing that chemical species to be identified.17 It was found that the synchrotron source provides sufficient flux to achieve good contrast between lithium metal and solid polymer electrolyte membranes enabling one to image lithium metal dendrites.15
The study discussed herein uses a high modulus, block copolymer electrolyte membrane.18 These high modulus membranes suppress lithium dendrite growth, lengthening the lifetime of batteries.19,20 However, dendrites still eventually puncture the membrane causing the battery to fail by short-circuit. It is important to understand the nature of dendrite formation and growth in these high modulus electrolyte membranes in order to design strategies to prevent their growth.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Anhydrous N-methyl-2-pyrrolidone&#160;</td>
			<td>MILLIPORE</td>
			<td>MX1396-7</td>
			<td></td>
		</tr>
		<tr>
			<td>Lithium bis(trifluoromethane)sulfonamide</td>
			<td>MILLIPORE</td>
			<td>8438730010</td>
			<td></td>
		</tr>
		<tr>
			<td>Lithium metal</td>
			<td>FMC Lithium</td>
			<td>None</td>
			<td>Lectro Max 100</td>
		</tr>
		<tr>
			<td>Pouch material</td>
			<td>MTI Corporation</td>
			<td>EQ-alf-400-7.5M</td>
			<td></td>
		</tr>
		<tr>
			<td>Nickel tabs</td>
			<td>MTI Corporation</td>
			<td>EQ-PLiB-NTA3</td>
			<td></td>
		</tr>
	</tbody>
</table>

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.

Wenn die oben beschriebene symmetrische Lithium-Lithium-Zellen werden bei 90 ° C gefahren, sieht die Spannungsantwort wie in Abbildung 1 gezeigt ist. Schließlich wird Lithiumdendriten durch den Elektrolyten zu wachsen und der Zelle führen, durch Kurzschluß ausfallen. Wenn dies geschieht, wird der Spannungsantwort auf den angelegten Strom auf 0,00 V. Dendriten fallen, wie in Figur 2 gezeigt in Proben, die durch Kurzschluss ausgefallen angezeigt. Nichtelektrolyt spann...

Watch this Scientific Journal Video about Failure Analysis of Batteries Using Synchrotron-based Hard X-ray Microtomography at JoVE.com

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

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.

Fehleranalyse von Batterien unter Verwendung Synchrotron-basierte Feströntgenmikrotomographie

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

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8.8K Aufrufe.  University of California Berkeley. 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.

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

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.

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

Charakterisierung von Elektrodenmaterialien für Lithium-Ionen und Natrium-Ionen-Batterien mit Synchrotronstrahlung Techniken

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

Forschung

Ingenieurwesen

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.

In Situ Neutronenpulver Mit Maßgeschneiderte Lithium-Ionen-Batterien

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

Reservoir Condition Pore-scale Imaging of Multiple Fluid Phases Using X-ray Microtomography

X-ray microtomography was used to image, at a resolution of 6.6 &#181;m, the pore-scale arrangement of residual carbon dioxide ganglia in the pore-space of a carbonate rock at pressures and temperatures representative of typical formations used for CO2 storage. Chemical equilibrium between the CO2, brine and rock phases was maintained using a high pressure high temperature reactor, replicating conditions far away from the injection site. Fluid flow was controlled using high pressure high temperature syringe pumps. To maintain representative in-situ conditions within the micro-CT scanner a carbon fiber high pressure micro-CT coreholder was used. Diffusive CO2 exchange across the confining sleeve from the pore-space of the rock to the confining fluid was prevented by surrounding the core with a triple wrap of aluminum foil. Reconstructed brine contrast was modeled using a polychromatic x-ray source, and brine composition was chosen to maximize the three phase contrast between the two fluids and the rock. Flexible flow lines were used to reduce forces on the sample during image acquisition, potentially causing unwanted sample motion, a major shortcoming in previous techniques. An internal thermocouple, placed directly adjacent to the rock core, coupled with an external flexible heating wrap and a PID controller was used to maintain a constant temperature within the flow cell. Substantial amounts of CO2 were trapped, with a residual saturation of 0.203 &#177; 0.013, and the sizes of larger volume ganglia obey power law distributions, consistent with percolation theory.

We present a methodology for the imaging of multiple fluid phases at reservoir conditions by the use of x-ray microtomography. We show some representative results of capillary trapping in a carbonate rock sample.

Reservoir Zustand Pore angelegte Imaging von mehreren fluiden Phasen Mit Hilfe der Röntgenmikrotomographie

X-ray microtomography was used to image, at a resolution of 6.6 &#181;m, the pore-scale arrangement of residual carbon dioxide ganglia in the pore-space ...

Energy Dispersive X-ray Tomography for 3D Elemental Mapping of Individual Nanoparticles

Energy dispersive X-ray spectroscopy within the scanning transmission electron microscope (STEM) provides accurate elemental analysis with high spatial resolution, and is even capable of providing atomically resolved elemental maps. In this technique, a highly focused electron beam is incident upon a thin sample and the energy of emitted X-rays is measured in order to determine the atomic species of material within the beam path. This elementally sensitive spectroscopy technique can be extended to three dimensional tomographic imaging by acquiring multiple spectrum images with the sample tilted along an axis perpendicular to the electron beam direction.
Elemental distributions within single nanoparticles are often important for determining their optical, catalytic and magnetic properties. Techniques such as X-ray tomography and slice and view energy dispersive X-ray mapping in the scanning electron microscope provide elementally sensitive three dimensional imaging but are typically limited to spatial resolutions of &gt; 20 nm. Atom probe tomography provides near atomic resolution but preparing nanoparticle samples for atom probe analysis is often challenging. Thus, elementally sensitive techniques applied within the scanning transmission electron microscope are uniquely placed to study elemental distributions within nanoparticles of dimensions 10-100 nm.
Here, energy dispersive X-ray (EDX) spectroscopy within the STEM is applied to investigate the distribution of elements in single AgAu nanoparticles. The surface segregation of both Ag and Au, at different nanoparticle compositions, has been observed.

The use of energy dispersive X-ray tomography in the scanning transmission electron microscope to characterize elemental distributions within single nanoparticles in three dimensions is described.

Energieröntgentomografie für 3D-Elementar Zuordnung einzelner Nanopartikel

Energy dispersive X-ray spectroscopy within the scanning transmission electron microscope (STEM) provides accurate elemental analysis with high spatial ...

Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating

A procedure for a technique to measure the transverse coherence of synchrotron radiation X-ray sources using a single phase grating interferometer is reported. The measurements were demonstrated at the 1-BM bending magnet beamline of the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). By using a 2-D checkerboard &#960;/2 phase-shift grating, transverse coherence lengths were obtained along the vertical and horizontal directions as well as along the 45&#176; and 135&#176; directions to the horizontal direction. Following the technical details specified in this paper, interferograms were measured at different positions downstream of the phase grating along the beam propagation direction. Visibility values of each interferogram were extracted from analyzing harmonic peaks in its Fourier Transformed image. Consequently, the coherence length along each direction can be extracted from the evolution of visibility as a function of the grating-to-detector distance. The simultaneous measurement of coherence lengths in four directions helped identify the elliptical shape of the coherence area of the Gaussian-shaped X-ray source. The reported technique for multiple-direction coherence characterization is important for selecting the appropriate sample size and orientation as well as for correcting the partial coherence effects in coherence scattering experiments. This technique can also be applied for assessing coherence preserving capabilities of X-ray optics.

The measurement protocol and data analysis procedure are given for obtaining transverse coherence of a synchrotron radiation X-ray source along four directions simultaneously using a single 2-D checkerboard phase grating. This simple technique can be applied for complete transverse coherence characterization of X-ray sources and X-ray optics.

Messung der Röntgenstrahl Coherence entlang mehreren Richtungen unter Verwendung von 2-D-Schachbrett Phase Grating

A procedure for a technique to measure the transverse coherence of synchrotron radiation X-ray sources using a single phase grating interferometer is ...

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.

Mit Synchrotronstrahlung Mikrotomographie Mehrskalige Dreidimensionale Mikroelektronische Bauteile zur Untersuchung

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

Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery

We demonstrate a method for electrochemical testing of an aprotic Li-O2 battery. An aprotic Li-O2 battery is made of a Li-metal anode, an aprotic electrolyte, and an O2-breathing cathode. The aprotic electrolyte is a solution of lithium salt with aprotic solvent; and porous carbon is commonly used as the cathode substrate. To improve the performance, an electrocatalyst is deposited onto the porous carbon substrate by certain deposition methods, such as atomic layer deposition (ALD) and wet-chemistry reaction. The as-prepared cathode materials are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray absorption near edge structure (XANES). A Swagelok-type cell, sealed in a glass chamber filled with pure O2, is used for the electrochemical test on a battery test system. The cells are tested under either capacity-controlled mode or voltage controlled mode. The reaction products are investigated by electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and Raman spectroscopy to study the possible pathway of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). This protocol demonstrates a systematic and efficient arrangement of routine tests of the aprotic Li-O2 battery, including the electrochemical test and characterization of battery materials.

Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery

A protocol for the electrochemical testing of an aprotic Li-O2 battery with the preparation of electrodes and electrolytes and an introduction of the frequently used methods of characterization is presented here.

Protokoll der elektrochemischen Prüfung und Charakterisierung von aprotische Li-O<sub&gt; 2</sub&gt; Batterie

We demonstrate a method for electrochemical testing of an aprotic Li-O2 battery. An aprotic Li-O2 battery is made of a Li-metal anode, an aprotic ...

Dynamic Pore-scale Reservoir-condition Imaging of Reaction in Carbonates Using Synchrotron Fast Tomography

Underground storage permanence is a major concern for carbon capture and storage. Pumping CO2 into carbonate reservoirs has the potential to dissolve geologic seals and allow CO2 to escape. However, the dissolution processes at reservoir conditions are poorly understood. Thus, time-resolved experiments are needed to observe and predict the nature and rate of dissolution at the pore scale. Synchrotron fast tomography is a method of taking high-resolution time-resolved images of complex pore structures much more quickly than traditional &#181;-CT. The Diamond Lightsource Pink Beam was used to dynamically image dissolution of limestone in the presence of CO2-saturated brine at reservoir conditions. 100 scans were taken at a 6.1 &#181;m resolution over a period of 2 hours. The images were segmented and the porosity and permeability were measured using image analysis and network extraction. Porosity increased uniformly along the length of the sample; however, the rate of increase of both porosity and permeability slowed at later times.

Synchrotron fast tomography was used to dynamically image dissolution of limestone in the presence of CO2-saturated brine at reservoir conditions. 100 scans were taken at a 6.1 &#181;m resolution over a period of 2 h.

Dynamische Pore-Skala Reservoir-Zustand Abbildung von Reaktions in Karbonate mit Synchrotronstrahlung Schnelle Tomography

Underground storage permanence is a major concern for carbon capture and storage. Pumping CO2 into carbonate reservoirs has the potential to dissolve ...

Applying X-ray Imaging Crystal Spectroscopy for Use as a High Temperature Plasma Diagnostic

X-ray spectra provide a wealth of information on high temperature plasmas; for example electron temperature and density can be inferred from line intensity ratios. By using a Johann spectrometer viewing the plasma, it is possible to construct profiles of plasma parameters such as density, temperature, and velocity with good spatial and time resolution. However, benchmarking atomic code modeling of X-ray spectra obtained from well-diagnosed laboratory plasmas is important to justify use of such spectra to determine plasma parameters when other independent diagnostics are not available. This manuscript presents the operation of the High Resolution X-ray Crystal Imaging Spectrometer with Spatial Resolution (HIREXSR), a high wavelength resolution spatially imaging X-ray spectrometer used to view hydrogen- and helium-like ions of medium atomic number elements in a tokamak plasma. In addition, this manuscript covers a laser blow-off system that can introduce such ions to the plasma with precise timing to allow for perturbative studies of transport in the plasma.

X-ray spectra provide a wealth of information on high temperature plasmas. This manuscript presents the operation of a high wavelength resolution spatially imaging X-ray spectrometer used to view hydrogen- and helium-like ions of medium atomic number elements in a tokamak plasma.

Anwenden von Röntgen Imaging Kristall Spektroskopie für den Einsatz als Hochtemperatur-Plasmadiagnose

X-ray spectra provide a wealth of information on high temperature plasmas; for example electron temperature and density can be inferred from line ...

Synchrotron X-ray Microdiffraction and Fluorescence Imaging of Mineral and Rock Samples

In this report, we describe a detailed procedure for acquiring and processing&#160;x-ray microfluorescence (&#956;XRF), and Laue and powder microdiffraction two-dimensional (2D) maps at beamline 12.3.2 of the Advanced Light Source (ALS), Lawrence Berkeley National Laboratory. Measurements can be performed on any sample that is less than 10 cm x 10 cm x 5 cm, with a flat exposed surface. The experimental geometry is calibrated using standard materials (elemental standards for XRF, and crystalline samples such as Si, quartz, or Al2O3 for diffraction). Samples are aligned to the focal point of the x-ray microbeam, and raster scans are performed, where each pixel of a map corresponds to one measurement, e.g., one XRF spectrum or one diffraction pattern. The data are then processed using the in-house developed software XMAS, which outputs text files, where each row corresponds to a pixel position. Representative data from moissanite and an olive snail shell are presented to demonstrate data quality, collection, and analysis strategies.

We describe a beamline setup meant to carry out rapid two-dimensional x-ray fluorescence and x-ray microdiffraction mapping of single crystal or powder samples using either Laue (polychromatic radiation) or powder (monochromatic radiation) diffraction. The resulting maps give information about strain, orientation, phase distribution, and plastic deformation.