Meaning
Analytical measurement of microstructural strain in crystalline materials utilizes non-destructive diffraction techniques to evaluate internal force distributions. The evaluation of x-ray diffraction residual stress maps the lattice spacing changes within copper collectors, electrode coatings, and structural cell casings. This measurement is crucial for determining how machining, coating, and cycling operations affect the mechanical longevity of battery components.
Measurement Principle
Stress evaluation using x-rays relies on detecting changes in the angle of diffraction from crystalline planes. Calculating the x-ray diffraction residual stress involves measuring the shift in diffraction peak positions when the sample is rotated through different angles. This shift reveals whether the material is under tensile or compressive stress, allowing engineers to predict where fractures are likely to form.
By analyzing these shifts across multiple sample points, a complete map of mechanical tension can be constructed for critical structural components.
Process Optimization
Sourcing and manufacturing teams use strain data to optimize manufacturing processes such as calendering and welding. Monitoring the x-ray diffraction residual stress in calendered electrodes helps to adjust the roller pressure, preventing the formation of micro-cracks in the active material coatings. This optimization reduces the defect rate and increases the uniformity of the finished electrodes.
Fatigue Prevention
Mechanical failure under dynamic loading is often accelerated by high levels of pre-existing tension within the material structure. Reducing the x-ray diffraction residual stress through controlled annealing or post-weld treatments prevents premature structural failures during transport and operation. This mechanical stabilization is essential for ensuring that welded tabs and electrical busbars do not fail under vibration.
