Battery aging degree evaluation method and device

Abstract

The invention discloses a battery aging degree evaluation method and device. The method comprises the steps of obtaining a set of CT images of a cross section of a to-be-tested battery in a single direction; and determining an evaluation value for evaluating the aging degree of the battery according to the SSIM between the CT images. The device comprises a collection module, which is used for obtaining the set of CT images of the cross section of the to-be-tested battery in the single direction; and a processing module used for determining the evaluation value for evaluating the aging degree of the battery according to the SSIM between the CT images. The aging degree is determined through the SSIM between the CT images, computer processing can be introduced, and the processing speed and accuracy are greatly improved.

Description

technical field

[0001] The invention relates to battery technology, in particular to a battery aging degree evaluation method and device. Background technique

[0002] Currently, with the widespread application of electric vehicles and electronic products using batteries. A lot of batteries that have not reached the level of end-of-life are replaced. For the sake of practicality, lithium-ion batteries can be used in cascades after strict screening to exert the remaining economic value.

[0003] At present, most of the methods for evaluating the aging degree of batteries are based on methods that are harmful to batteries, such as cycle charge and discharge aging tests, and CT image analysis, as a means of non-destructive analysis, is based on the fact that batteries with good electrochemical performance have fewer internal structures. Therefore, the images on each cross-section of the battery will have higher consistency, while the battery with poor electrochemical performa...

Examples

Embodiment 1

[0030] refer to figure 1 , showing a battery aging degree evaluation method, including:

[0031] S1. Obtain a collection of CT images of cross-sections in a single direction of the battery to be tested;

[0032] S2. Determine an evaluation value for evaluating battery aging according to the SSIM between CT images.

[0033] Such as figure 2 The CT scan example shown includes the overall scan image of the battery on the left and the cross-sectional scan image on the right; obtain the CT image of the cross-section of the battery to be tested in a single direction, for example, the horizontal concept is perpendicular to the electrode direction, and the vertical direction is The electrode direction, and so on; the CT process does not only scan one layer, but continues to scan along a certain direction (designated axis direction), so a large number of images will be generated, that is, a collection of CT images. According to the value of SSIM between different CT images, the eva...

Embodiment 2

[0046] An embodiment of the present invention provides a battery aging evaluation device, including: a collection module 1, used to acquire a collection of CT images of sections in a single direction of the battery to be tested; a processing module 2, used to The SSIM between determines the evaluation value used to evaluate the degree of battery aging.

Embodiment 3

[0048] The purpose of this embodiment is to provide specific examples to explain the technical solution in Embodiment 1.

[0049] (1) The battery is scanned using the axial helical scanning method (that is, the method of rotating around the specified axis). Taking the Werth TomoScop XS instrument as an example, a battery can obtain a total of 2,500 CT images. It is worth noting that the spiral CT method allows the tube to rotate continuously and the bed surface to move in a directional manner, so that projection data can be collected without interruption. Therefore, one battery, after helical scanning, can obtain hundreds to thousands of CT images at different positions, and the number depends on the accuracy of the instrument.

[0050] (2) Extract 15 CT images equidistantly. For example, assuming that the CT equipment scans 1500 CT pictures, and the pictures are numbered according to the shooting sequence 1-1500, then one picture is selected every 100 numbers, so 15 CT pictu...

technical field

[0001] The invention relates to battery technology, in particular to a battery aging degree evaluation method and device. Background technique

[0002] Currently, with the widespread application of electric vehicles and electronic products using batteries. A lot of batteries that have not reached the level of end-of-life are replaced. For the sake of practicality, lithium-ion batteries can be used in cascades after strict screening to exert the remaining economic value.

[0003] At present, most of the methods for evaluating the aging degree of batteries are based on methods that are harmful to batteries, such as cycle charge and discharge aging tests, and CT image analysis, as a means of non-destructive analysis, is based on the fact that batteries with good electrochemical performance have fewer internal structures. Therefore, the images on each cross-section of the battery will have higher consistency, while the battery with poor electrochemical performa...

Examples

Embodiment 1

[0030] refer to figure 1 , showing a battery aging degree evaluation method, including:

[0031] S1. Obtain a collection of CT images of cross-sections in a single direction of the battery to be tested;

[0032] S2. Determine an evaluation value for evaluating battery aging according to the SSIM between CT images.

[0033] Such as figure 2 The CT scan example shown includes the overall scan image of the battery on the left and the cross-sectional scan image on the right; obtain the CT image of the cross-section of the battery to be tested in a single direction, for example, the horizontal concept is perpendicular to the electrode direction, and the vertical direction is The electrode direction, and so on; the CT process does not only scan one layer, but continues to scan along a certain direction (designated axis direction), so a large number of images will be generated, that is, a collection of CT images. According to the value of SSIM between different CT images, the eva...

Embodiment 2

[0046] An embodiment of the present invention provides a battery aging evaluation device, including: a collection module 1, used to acquire a collection of CT images of sections in a single direction of the battery to be tested; a processing module 2, used to The SSIM between determines the evaluation value used to evaluate the degree of battery aging.

Embodiment 3

[0048] The purpose of this embodiment is to provide specific examples to explain the technical solution in Embodiment 1.

[0049] (1) The battery is scanned using the axial helical scanning method (that is, the method of rotating around the specified axis). Taking the Werth TomoScop XS instrument as an example, a battery can obtain a total of 2,500 CT images. It is worth noting that the spiral CT method allows the tube to rotate continuously and the bed surface to move in a directional manner, so that projection data can be collected without interruption. Therefore, one battery, after helical scanning, can obtain hundreds to thousands of CT images at different positions, and the number depends on the accuracy of the instrument.

[0050] (2) Extract 15 CT images equidistantly. For example, assuming that the CT equipment scans 1500 CT pictures, and the pictures are numbered according to the shooting sequence 1-1500, then one picture is selected every 100 numbers, so 15 CT pictu...

Images