An imaging system for online detection and analysis, automatic online or offline detection of square polymer soft cover bare cells or finished batteries. The device emits X-rays through the X-RAY generator, penetrates the inside of the battery, receives X-rays and images and takes pictures by the line array detector. The image is processed and automatically measured and judged by the self-developed detection software, determines the good and bad products, and selects the bad products. The front and back ends of the device can be connected with each other.