Method for Analyzing the Cracking Rate of Electrode Active Materials for Secondary Batteries

Rapid, Pretreatment-Free Analysis Method for Quantifying Active Material Pulverization via XRD Full Width at Half Maximum (FWHM) Changes

This technology analyzes electrodes before and after electrochemical reactions using X-ray diffraction (XRD) and quantifies the degree of pulverization and cracking of active material particles by measuring changes in the Full Width at Half Maximum (FWHM) of the diffraction peaks.

Conventional cross-sectional image analysis methods are hindered by complex and time-consuming sample preparation, such as resin impregnation and ion milling. Consequently, it has been difficult to quickly and quantitatively assess the level of cracking and pulverization in active materials.

This technology eliminates the need for separate pretreatment by measuring the XRD pattern of the electrode surface or a cut cross-section. The degree of cracking is calculated by substituting the FWHM value before the reaction (A) and after the reaction (B) into the formula: Cracking Rate (%) = (1 - A/B) × 100. It can be applied to quality control lines for cathode manufacturers, optimization of high-pressure rolling electrode processes, and degradation diagnostics for long-life cell development, allowing for the rapid comparative evaluation of multiple samples and replacing cross-sectional observation methods that take hours.

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Key Features:

• Measuring the X-ray diffraction pattern of the electrode and processing the data to determine the FWHM value of the electrode active material peaks.
• Selecting two to three effective diffraction peaks from the measured X-ray diffraction pattern to obtain an average FWHM value.
• Calculating the cracking rate by substituting the FWHM values before and after the electrochemical reaction (A and B) into the formula (1 - A/B) × 100%.
• Performing X-ray diffraction analysis on the exposed electrode active material layer surface after cutting the electrode to a specific depth.

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