Lithium-ion battery X-ray foreign body detector

Seiko Instruments has successfully developed a detection instrument that can automatically perform elemental analysis and quickly detect the tiny metal about 20 μm that may be doped in the electrodes of lithium-ion rechargeable batteries and fuel cells within minutes. foreign body. This test machine will be exhibited on September 7-9.

Lithium-ion rechargeable batteries and fuel cells do not contain metallic foreign materials, which is an important reason for the reduction of the yield and life of batteries. Lithium-ion rechargeable batteries in particular heat up and may cause a fire. In recent years, with the car? As batteries for electric oil hybrid vehicles and residential applications are gradually enlarged, the prevention of the incorporation of metallic foreign materials becomes more important. Therefore, in order to prevent the incorporation of metallic foreign materials, a complex fault analysis was performed centering on the battery manufacturer.

The method of incorporation of metallic foreign materials is caused by the incorporation of active materials [1], separators [2], and other materials, as well as painting and other production projects. In the past, the failure analysis was performed by removing the bad battery, detecting the existence of a metal foreign substance through the X-ray penetration inspection apparatus and the microscope, and then using a specific target element such as a scanning electron microscope and an X-ray fluorescence analyzer, and then speculating that the way. However, due to the limitations of the instrument performance, these methods are difficult to detect metal foreign objects below 50 μm, and it is also one of the problems that the detection time is very long. In addition, due to elemental analysis of detected foreign materials using other instruments, there is a possibility that no place to be detected may be found.

Recently, SIINT has integrated X-ray penetration for metal foreign matter detection and X-ray fluorescence for elemental analysis, and has developed the world's first X-ray foreign body inspection device capable of detecting and analyzing minute metal foreign materials of about 20 μm.

Put the electrode plate and separator, the active material contained in the container into the instrument, select the inspection order, just click to start the measurement, the photograph from the X-ray penetration image to the metal foreign object detection and element analysis can be automatically run. In addition, the analysis results include the number of metal foreign objects in the sample, the composition and size of each foreign matter, and the observation image of the microscope. Since no preprocessing is required and it is completely automatic, it is easy for anyone to perform failure analysis. Sampling inspection.

X-ray foreign body detector main features:

1. A metal foreign material of about 20 μm in A4 size sample can be detected in a few minutes. For example, a metal foreign material of about 20 μm in the battery electrode of A4 size needs to be detected. The conventional X-ray penetration inspection instrument requires several hours of imaging time. ※1 . SIINT has shortened the shooting time significantly by adopting the latest X-ray tube and detector and new image processing technology. The detection speed has successfully achieved more than 100 times. The A4 size battery electrode can be used for imaging in 3 to 6 minutes to detect metal foreign objects of about 20 μm and detect them automatically.

2. Significant increase in the speed of element recognition The detected metallic foreign materials are automatically analyzed by X-ray fluorescence. This instrument is equipped with a high-brightness X-ray optical system developed by our company. The recognition rate of metal foreign objects of about 20 μm is 10 times faster than that of conventional instruments.

3, the integration of operations, to improve the efficiency of the X-ray penetration tester and element analyzers and microscopes are included in a single instrument, each system can be combined to fully automatic output measurement results. Therefore, the operator only needs to place a good sample to obtain the measurement result, which greatly improves the working efficiency.

[1] Active substance: A substance that absorbs electrons or releases electrons through a chemical reaction with an electrolyte. An electron-absorbing active material is called a positive electrode active material, and an electron-emitting active material is called a negative electrode active material.

[2] Separator: Insulate the positive and negative electrodes with a thin film (polyethylene: PE or polypropylene: PP) with numerous tiny holes.