Measuring the thickness of wet layers in battery production

In the production of battery cells, films are coated continuously or intermittently. The film thickness and the coating thickness represent a process-critical measurement parameter. Precise thicknessGAUGE measuring systems from Micro-Epsilon monitor these values with high accuracy during ongoing production.

In the coating process of anode and cathode material, the film and coating thickness, the purity and the surface quality are decisive parameters for the quality of the end product. The thicknessGAUGE inline measuring system monitors the wet film thickness to an accuracy of <±1 μm at 150 to 500 µm object thickness. The system consists of a linear unit with electromechanical drive, two confocal chromatic distance sensors, an automatic calibration unit and a multi-touch panel IPC.

The high precision and the measuring rate of up to 5 kHz enable fully automated thickness measurement during ongoing production. The confocal sensors measure the material surface from two sides based on the differential method. The distance between the sensors is continuously determined via automatic calibration to a reference target. The material thickness is calculated from the sensor distance and the two distance values. The high resolution of the confocal sensors enables measurement of the smallest of thickness deviations.

The thicknessGAUGE can be used for fixed track measurements, for example, to determine the center thickness or the thickness measurement at the edges. Using the linear axis to move the thicknessGAUGE over the strip allows the complete cross profile to be determined by traversing. Up to 400 m strip width can be measured via traversing thickness measurements.