Capacity Fading Detection of Rectangular LiFePO_4 Battery by Tomographic Image

摘要

Detection of the power battery capacity and its fading is still a problem, owing to the commonly test method time-consuming and destructively. Based on the principle of battery electrochemistry and computer tomography, the X-ray computed tomography image detection of battery capacity fading is proposed because of the advantage of quick, accurate and non-destructive. A kind of typical rectangular LiFePO_4 battery which used in pure electric vehicle is experiment object. The structure morphological change is extracted by tomography image of battery in different capacity fading. Combining with the traditional electrochemical performance detection, the relationship between the electrochemical performance parameter and the structure morphological parameter is studied. The experimental result shows that the variation of active material's area is relate to the capacity fading of battery. The more the active material's area decrease, the more the capacity fading. The X-ray computed tomography image detection method is a practical, quickly, and non-destructively method to detect capacity fading.