This study designed an in situ XRD jig for lithium-ion battery electrode analysis and evaluated its preliminary XRD applicability under different static sample configurations prior to operando charge–discharge measurements. The developed jig was designed with an X-ray transmission window at the upper part so that X-rays could be directly irradiated onto the electrode surface. It was fabricated by considering electrolyte sealing, electrode fixation, electrical contact stability, and repeated assembly reliability. To verify the XRD applicability of the jig, spinel-structured Li4Ti₅O12, which has excellent structural stability, was used as a reference active material. The XRD results showed that the characteristic diffraction peaks corresponding to the spinel structure were clearly observed in both the Li4Ti₅O12 standard sample and the powdered active material. In the composite electrode, the main peak positions of the active material were maintained, although peak intensity decreased and background signals increased due to the influence of the conductive additive and binder. In the film-attached electrode, X-ray absorption and scattering by the film caused partial peak attenuation and increased background signals. However, the main peak positions remained unchanged, indicating that the crystal structure of the active material was preserved. In the electrode equipped with a beryllium window, strong additional diffraction peaks originating from beryllium were observed together with the diffraction peaks of the active material. The origin of these peaks was confirmed through XRD analysis of the beryllium sheet alone, demonstrating that prior measurement and correction of background signals from the window material are essential for accurate in situ XRD analysis. Overall, the developed in situ XRD jig was able to reliably detect key crystallographic information from lithium-ion battery electrode active materials. The results confirm its potential as an experimental platform for future analysis of peak shifts, phase transitions, and lattice changes during charge and discharge processes.
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Abstract 1. 서론 2. 재료 및 방법 2.1 XRD 분석 전용 인시투 설계 2.2 인시투 지그 구성 재료 및 제작 2.3 전극 셀 조립 및 전기화학적 조건 2.4 인시투 XRD 측정 및 결정구조 분석 3. 결과 및 고찰 3.1 XRD 분석 3.2 Li4Ti5O12 시편의 결정상 확인 3.3 분말 활물질 및 복합 전극의 XRD 특성 3.4 필름 부착 복합 전극의 XRD 특성 3.5 베릴륨 윈도우 장착 전극의 XRD 특성 3.6 베릴륨 시트의 배경 신호 분석 3.7 인시투 지그 설계의 유효성 및 개선 방향 4. 결론 후기 References