Rigaku Corporation

This application note demonstrates the measurement by X-ray diffraction (XRD) of positive electrode material from lithium ion batteries during the charge/discharge process.

	Lithium ion secondary batteries are widely used in small portable devices such as mobile phones. Research and development of lithium ion batteries for use in automobiles and larger machines is an active field. To develop lithium ion secondary batteries with high capacity, high stability and long life, it is essential to evaluate the stability of the positive electrode material during the charge/discharge process. Operando X-ray diffraction measurements using an attachment that reproduces the charge/discharge environment and a 2D detector that can perform high-speed measurements enables detailed observation of crystal phase changes while a battery is in use, making it suitable for studying battery performance and life.


	Figure 1: Figure 1 shows a picture and an illustration of the cross-sectional structure of a battery cell attachment. The positive electrode material was LiMn

. Measurement using an exposure time of 15 s was repeated while charging/discharging the electrode at a charge and discharge rate 1C = 132 mAh/g. Changes to the X-ray diffraction profile over time were investigated.

	X-ray diffraction measurements of the positive electrode material during high-speed charging and discharging were carried out with a battery cell attachment and a HyPix-3000 2D detector on a Rigaku SmartLab X-ray diffractometer.


	Figure 2: Figure 2 shows the multiple 1D XRD profiles, 2D profile maps and voltage graphs. Two steps of a two-phase coexistence reaction occurred with charging and discharging. After charging and discharging, the electrode material returned to the same crystal phase as before the measurement started.

	The Rigaku SmartLab Automated multipurpose X-ray diffractometer with HyPix-3000Hybrid pixel array multi-dimensional detector can perform high-speed Operando measurements of crystal phase changes of lithium ion batteries to evaluate battery performance and life.


	Figure 3: Rigaku SmartLab automated multipurpose X-ray diffractometer (XRD) with Guidance software.


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	tel. (281) 362-2300, fax (281) 364-3628
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Operando Measurement of Li Ion Battery Positive Electrode in Charge/Discharge Process by X-ray Diffraction

This application note demonstrates the capabilities of a low-cost, benchtop WDXRF spectrometer for rapid quantitative elemental analysis of cement raw meal.

	Cement is one of the most important materials in the construction industry. Since its physical properties and those of the concrete ultimately made from it depend on its composition, it is important to monitor the composition of the raw meal used to make the clinker.

	Thanks to simple sample preparation and routine operation, short measurement times and high precision, X-ray fluorescence (XRF) spectrometry has become the technique of choice for elemental analysis at all points in cement production: from alternative fuels, raw materials and raw meal to clinker and final certification. Wavelength-dispersive (WD) XRF is the most commonly utilized analytical technique in the cement industry because it offers the highest throughput, precision and sensitivity, especially for essential light elements, such as Na, S, and K.

	Traditionally, WDXRF spectrometers used in cement plants have been large, floor-standing models with substantial installation requirements and ownership expenses. As the industry strives for greater efficiency, operators have increasingly sought equipment that is less expensive to acquire and less costly to maintain.

	The Supermini200 is a benchtop sequential wavelength-dispersive X-ray fluorescence (WDXRF) spectrometer designed specifically to deliver high performance while eliminating typical installation requirements, such as cooling water, special power supply, large floor space, etc.

	Featuring a unique air-cooled 200W X-ray tube, two detectors and three analyzing crystals, the Supermini200 can analyze all relevant elements in just minutes with full spectral separation of all peaks, high sensitivity for light elements, such as Na, Mg, P and Cl, and exceptional repeatability.

	The Windows-based software running the Supermini200 is shared with Rigaku's higher- power Primus series of WDXRF systems.

	The pressed powder method is the most common sample preparation technique in XRF because it does not require an expensive flux, fusion machine, or highly-trained operators. For this report, cement raw meal powders were pulverized and pressed into aluminum rings at 120 kN.

	Measurements were performed in vacuum on the Supermini200 with the 200W Pd target X-ray tube operating at 50 kV and 4.0 mA and using the standard crystals: LiF(200), PET, and RX25. The total analysis time for all of the analytes was about four min per sample.

	A series of reference materials of cement raw meal certified by CSBTS (China State Bureau of Technical Supervision) was used for calibration. The calibration results are presented in Table I.

	One of the reference materials, used in the calibration, was measured consecutively 10 times to determine the short-term stability of the method and instrument. The results show that it is possible to analyze pressed pellets of cement raw meal with high repeatability on a 200W WDXRF instrument that is small enough to fit on a bench.

	This report demonstrates that cement raw meal samples can be routinely analyzed by the pressed powder method with excellent accuracy and precision on the Rigaku Supermini200 low-cost benchtop sequential WDXRF spectrometer that does not require cooling water or special facility accommodations.


	9009 New Trails Drive, The Woodlands TX 77381
	tel. (281) 362-2300, fax (281) 364-3628
	Website: 

Cement Raw Meal Analysis by the Pressed Powder Method on Supermini200 Benchtop WDXRF

Semi-quantitative analysis in modern XRF instruments is a unique method which is performed without reference materials for the unknown samples. This report demonstrates determination of chemical composition in geological samples using semi-quantitative analysis by the pressed powder method on a WDXRF spectrometer.

Semi-Quantitative Analysis for Geological Samples

The permitted sulfur limit in fuel oils has been decreased to 10 ppm in many regions. This application note demonstrates that the performance of the Rigaku Micro-Z ULS meets the requirement of ASTM D2622-10, in the analysis of ultra-low sulfur in automotive fuels.

Recent developments in ultra-low sulfur (ULS) fuel have improved fuel efficiency and created cleaner exhaust gas. Globally, the permitted sulfur limit in fuel oils has been decreased to 10 ppm in many countries and regions. 

For compliance verification, X-ray fluorescence (XRF) spectrometry is the definitive analysis tool for use at distribution terminals and refineries, as well as mobile or stationary testing laboratories. In recent years, there has been an increasing need for an instrument which does not require the use of helium gas, for instances when acquisition or delivery of helium to the analysis site is difficult. 

The Micro-Z ULS (ultra-low sulfur) is a newly developed sulfur analyzer which does not require helium gas in operation. This application note demonstrates that Micro-Z ULS can meet the requirements of ASTM D2622-10. 

The Micro-Z ULS is a benchtop wavelength dispersive X-ray fluorescence (WDXRF) spectrometer with fixed optics optimized for sulfur analysis. The atmosphere in the optics path of the Micro-Z ULS is a vacuum, so that helium gas is not required. The spectrometer is designed to minimize the restrictions in installation such as the need for cooling water, a special power supply, and installation space. The Micro-Z ULS is equipped with an air-cooled 40 W Cr-target X-ray tube and a doubly curved RX-9 analyzing crystal optimized for low concentration sulfur. 

The Micro-Z ULS has a built-in operation panel, which enables simple and easy operation for daily analysis. The counting time was 300 s for peak and background measurements in this experiment. 

Approximately, 4 mL of each sample was poured into a liquid cell with sample film of 2.5 µm Mylar® film (Chemplex® 100). 

"Number 2 diesel fuel" standards and isooctane-based standards provided by VHG Labs, Inc. were used for calibrations of diesel fuel and gasoline respectively. 

 Figure 1: Calibration curve for each material of Micro-Z ULS; (a) diesel fuel, (b) isooctane (for gasoline).			

Repeatability tests were carried out using a representative sample for each material. For each sample, two aliquots were prepared and analyzed using the calibration Figure 1; this process was repeated 20 times. The term "r" represents "repeatability" defined by the following formula in ASTM D2622-10 (1): 

The difference between successive test results obtained by the same operator with the same apparatus under constant operation conditions on identical test material would exceed the values calculated by equation 1 only in one case in every 20. 

The test results, where the maximum value for each fuel is smaller than r, prove that the performance of the Micro-Z ULS meets the requirement of ASTM D2622-10 for diesel fuel and gasoline. 

Low concentration sulfur in petroleum-based fuel can be routinely analyzed with high accuracy and precision on the Micro-Z ULS, a benchtop WDXRF spectrometer with fixed optics, which does not require He gas, external water for cooling the X-ray tube, or special power supply. This application note demonstrates that the performance of the Micro-Z ULS meets the requirement of ASTM D2622-10, which has become strict in the recent versions of ASTM D2622. 

(1) ASTM D2622-10(2010), "Standard Test Method for Sulfur in Petroleum Products by Wavelength Dispersive X-ray Fluorescence Spectrometry," 

9009 New Trails Drive, The Woodlands TX 77381

The permitted sulfur limit in fuel oils has been decreased to 10 ppm in many regions.

Author | Rigaku Corporation

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