Aiming at the problems of low definition, poor contrast, and blurred electrode contours in lithium battery X-ray images, an X-ray image enhancement algorithm for lithium batteries based on improved multi-scale Retinex was proposed. First, in the traditional multi-scale Retinex algorithm,bilateral filtering is used to estimate the luminance component, while image dynamic range compression is performed globally adaptively based on the mean logarithmic luminance value. Then use the improved MSR algorithm to extract the reflection component of the image, use the sobel operator to obtain the longitudinal gradient of the reflection component, and then fuse the gradient information with the reflection component to enhance the image details, and then use the CLAHE algorithm to enhance the contrast of the fused image, and finally use Bilateral filtering is used to remove noise to obtain the final enhanced image. The experiments are carried out on the self-constructed data set. The experimental results show that the proposed method can significantly improve the clarity and contrast of X-ray images of lithium batteries, and the edge contours of the cathode lines in the images are significantly enhanced. It is significantly better than the traditional multi-scale Retinex algorithm in highlighting the edge details of lithium battery X-ray images and enhancing image contrast.