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.電解質の準備<ol><li> 260キロ/モルのポリ（スチレン） - - ブロック -ポリ（エチレンオキシド）コポリマー（SEO）アニオン重合を使用して240キロ/モルを合成します。 <ol><li>水と酸素レベルが制御されているアルゴングローブボックス内のすべての追加のサンプル調製を行い、残る&lt;5 ppmです。 </li><li>乾燥したリチウムビス（トリフルオロメタン）スルホンイミド（LiTFSIを）塩と無水N-メチル-2-ピロリドン（NMP）中のポリマー0.3gを溶解します。 13.13の質量比をSEOするSEO質量0.275の比率及びNMPへのLiTFSI塩を使用してください。 注：ポリマーのこの量は、約20のサンプルを作成するのに十分な大きさの膜が得られます。 </li><li>ドクターブレードを用いてニッケル箔の15センチメートル平方作品によって15cm程度上に、上記の手順で調製したポリマーと塩の混合物のすべてをキャストします。 60°のCO / Nで得られたフィルムを乾燥させます。 </li><li>乾燥させた後、ニッケル箔からフィルムを剥離し、9にて真空下でさらに乾燥させます0°C。 </li><li>後で使用するために、グローブボックス中で気密ボックスの内側にニッケル箔とストア内の結果、自立フィルムを包みます。 </li></ol></li></ol> 2.リチウム - リチウム対称細胞調製<ol><li>直径7/16は、丸い金属パンチは純度99.9％、バッテリーグレードのリチウム金属箔のロールから2リチウム金属電極をカットするために使用します。 </li><li>高分子電解質膜の一部をカットするために、直径メタルパンチで1/2を使用してください。 注意：リチウム金属は柔らかく、高分子電解質よりもパンチが容易です。 </li><li> 2リチウム金属電極間の高分子電解質膜を挟むと、電極上にニッケルタブを押してください。 </li><li>真空は、ポリプロピレン、ナイロン並ぶアルミニウム製気密袋にサンプルを密封します。 注：一つは完全な電池を研究したい場合、リチウム電極の一方を容易に陰極と交換されます。 </li></ol> 3.対称セルサイクリン<html>グラム<ol><li>電気化学サイクル装置を用いて90℃のサイクルで開催されたオーブン中に真空封止されたサンプルを置きます。電解質膜を介して妥当なイオン伝導性を達成するために、サイクル中の試料を加熱します。安全のために、試料は180℃のリチウム金属の融点に近づかないことを確認してください。 </li><li> 4時間試料を0.175ミリアンペア/ cm 2の電流密度をパスし、45分の休憩でください。次に、4時間試料を-0.175ミリアンペア/ cm 2の電流密度を渡し、45分の休憩でください。必要に応じて、何回もこのサイクリングルーチンを繰り返します。 </li><li>厚さ30μmのSEOの電解質を通過し、この電流密度のための電圧応答を観察し、 図1に示すものと比較します。電池がショートを示すことによって、失敗したため、セル電圧応答は、0.00 Vまで低下するとサイクリングルーチンを停止しますリチウムデンドライトの成長。 </li></ol>itle &quot;&gt; 4。シンクロトロン硬X線マイクロトモグラフィーイメージング<ol><li>対称セルを循環した後、グローブボックスにそれを戻すと、その袋から取り出します。 </li><li>ポーチ材料にセルの中央部をシールし、シンクロトロン施設への輸送のためにグローブボックスから削除cell.Vacuumの中央部分を切り出すために1/8インチの金属パンチを使用してください。 注：縮径試料を撮像することにより、X線検出器の視野の外側の材料の量が低減されます。これは、この余分な材料に起因するノイズを低減することによって全体的な画像品質を向上させます。さらに、高度にX線吸収ニッケル電流コレクタの除去は、明確なX線画像を取得するために、この特定のパウチ設計に必要です。 </li><li>一度ビームラインで、試料ステージにサンプルを固定するためにポリイミドテープを使用しています。必要に応じて、位置合わせを支援するために、サンプルの上に小さな金属マーカーをテープで固定します。 SAMPのほぼ中央に金属マーカーを置きますルは、サンプルを一度に整列回転し、その周りの場所をマークします。 </li><li>システム用に最適化露光時間で画像にサンプルを20 keVのX線を使用してください。スキャン時間やイメージ当たりのカウント数を均衡化することによって、露光時間を最適化します。収集した画像の数で露光時間を乗じて総スキャン時間を見積もります。 <ol><li>ここでは、5〜10分のスキャン時間で、その結果、300ミリ秒の露光時間を使用しています。 </li></ol></li><li>すべてのビームタイムシフトの開始時に光学レンズに関連するピクセルサイズを測定します。 注： 図2に示される画像を撮影するために使用される4倍のレンズの場合、画素サイズは1.61ミクロン/ピクセルでした。高倍率レンズ（10倍と20倍）も使用できます。 </li><li>それは180°回転すると、それは、検出器の視野に残るように、検出システムに対して回転ステージ上にサンプルを位置と合わせます。 </li><li>位置に近いサンプルサンプルは任意の回転角度で検出器に当たらないようにしながらなどの検出器が可能です。 注：距離の増加を検出器に試料として、フレネル位相差が再構成された画像でより顕著になるであろう。これは、機能を曖昧にし、貧しい解像度をもたらすことができます。ポーチセルの場合、検出器の距離にサンプルが離れて検出器3からcmのオーダーであるのが典型的です。 </li><li>一度0と180°の間のサンプルの回転にわたって収集1025の画像からなるスキャンを実行し、整列されます。 「明視野」を収集する視野からサン​​プルを移動させることにより画像（以下、「フラットフィールド」または「バックグラウンド」として知られています）。さらに、ビームがオフの間の画像を取ることによって、「暗視野」画像を収集。不均一な照明、シンチレータ応答、およびCCDカメラ応答のサンプル画像を正規化するためにこれらを使用してください。 </li></ol> 5.画像再構成<ol><li> Tomographically各画像は、次の手順を使用してボリューム内のスライスを表す画像のスタックに1025 X線写真のセットを再構築します。 <ol><li>まず、X線写真のイメージと「明視野」の画像の両方から「暗視野」画像を減算することにより、画像を正規化します。得られた「明視野」画像で割った結果のX線写真の画像を分割します。 </li><li>次に、断層撮影の再構成、投影角度のシリーズは、メーカーのプロトコールに従って正規化されたX線撮影画像に、3次元画像に変​​換するプロセスを実行します。 注：再構成ソフトウェアは、一連の画像を出力し、積層sample.Whenを通る水平スライスを表すそれぞれは、再構成画像のセットは、試料の三次元X線吸収マップを形成します。 </li></ol></li><li>サンプルが内側にどのように見えるかを確認するために、個々のスライスまたは3次元のサンプルを可視化。</li></ol> 6.データの可視化と処理<ol><li>データの可視化と分析のために利用可能な商用およびオープンソースの画像処理ソフトウェアパッケージの多数のいずれかを使用します。22、23 </li><li>希望のソフトウェアを使用して再構成された画像のスタックを開くと、再構成されたデータのxy、XZ、YZとの視点を表示するorthoslicesを作成します。 </li><li>これらの画像を通してパンと図2に示したリチウムデンドライトのように、関心のある特徴を検索します。 </li><li>次に、3次元の関心の機能をレンダリングするためにセグメンテーション（デジタルラベル）と3D描画ツールを使用しています。 </li><li>デジタルセグメント画像は、ラベルフィールドを作成し、材料に対応するサンプルの領域を選択するために、しきい値のツールを使用します。 </li><li> 図2（b）に示すような画像を再現するために、暗いピクセルのリチウムと明るいピクセル電解質を標識します。に含まれるリチウムをラベル上部と下部のリチウム電極とは別にデンドライト。 <ol><li>オレンジ樹状リチウムと青の中の高分子電解質をレンダリングします。グレーで上部と下部のリチウム金属電極をレンダリングし、オレンジ色の樹枝状リチウムを明らかに透明度の値を調整します。多くの視点から構造を表示するには、この3次元再構成を回転させます。 </li></ol></li></ol>

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The authors have nothing to disclose.

X線は大気に触れることなく、試料の容易なイメージングを可能にする、保護ポーチ材料を貫通することができますので、硬X線マイクロトモグラフィーは、多くの電気化学的に活性な物質のような空気に敏感なサンプルに特に適しています。おそらく、このイメージング技術の最も貴重な特徴は、貫通したX線は、ユーザーがそれを破壊することなく、試料の内部を見るために可能にすること...

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.

上記の対称性のリチウムリチウム電池を90℃で循環している場合、電圧応答は 、図1に示すようになります。最終的には、リチウムデンドライトが電解質を通って成長し、セルが短絡することにより失敗します。このとき、図2に示したものは、短絡によって故障したサンプルに表示されますように、印加電流に対する電圧応答は、0.00 Vの樹状突起にまで低下します。?...

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.

シンクロトロンベースのハードX線マイクロトモグラフィーを用いて電池の故障解析

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

failure-analysis-batteries-using-synchrotron-based-hard-x-ray

Research

JoVE Journal

Engineering

8.8K ビュー.  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.

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

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.

リチウムイオン電池のコイン細胞の構築とテスト

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

工学

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.

その場中性子粉末回折ではカスタムメイドのリチウムイオン電池を使用して、

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.

X線マイクロトモグラフィーを使用した複数の流体相の貯水池条件ポアスケールのイメージング

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.

個々のナノ粒子の3次元元素マッピングのためのエネルギー分散型X線トモグラフィー

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.

2次元チェッカーボード位相格子を使用して複数の方向に沿ってX線ビームコヒーレンスの測定

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.

マルチスケール三次元マイクロエレクト​​ロニクスパッケージを調査するために放射光マイクロトモグラフィーを用いて、

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.

非プロトン性のLi-Oの電気化学的試験のプロトコルとキャラクタリゼーション<sub&gt; 2</sub&gt;バッテリー

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.

シンクロトロン高速断層撮影法を使用した炭酸における反応の動的細孔スケール貯水池条件イメージング

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.

高温プラズマ診断として使用するためのX線イメージングクリスタル分光法を適用します

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.