Control method and control system of film thickness of slit coater

Abstract

The invention relates to a control method and control system of the film thickness of a slit coater. The control system comprises a wet material thickness measuring instrument for measuring the thickness of a wet material, a dry material thickness measuring device for measuring the thickness of a dry material, a comparator for comparing the results measured by the dry material thickness measuring instrument with a predetermined allowable range of the thickness of the dry material and transmitting the comparison results to a digital information processor, a calculator for calculating the ratio of the wet material to the dry material according to the on-line test values of the dry material thickness measuring instrument and the wet material thickness measuring instrument, a first storage device for storing the standard ratio of the wet material to the dry material, a second storage device for storing the temporary ratio of the wet material to the dry material, a digital information processor for coordinating with the wet material thickness measuring instrument, the dry material thickness measuring instrument, the comparator, the first storage device, the second storage device and an actuator to work according to a procedure, and the actuator for adjusting the coating gap of the coater. According to the control method and the control system, the uniformity of film thickness can be improved, and the film thickness of the dry material is ensured to be in an allowable error range.

Description

technical field [0001] The invention relates to a film thickness control method and a film thickness control system of a slit coating machine. Background technique [0002] Existing slit coaters generally include a coating machine head, a substrate retracting and unwinding device, and an electrode material drying device. Evenly coated on one side of the substrate, the substrate with the electrode slurry passes through a drying device to dry the electrode slurry, and fix the electrode material (also called electrode film) on the substrate. The positive electrode or negative electrode of the battery is produced by this coating machine, and the thickness of the electrode film has a great influence on the quality of the battery made in the subsequent process. Therefore, it is very important to control the thickness of the electrode film. [0003] The most traditional slit coater is to get the appropriate coating gap of the coating head by taking samples when starting up, and th...

AI Technical Summary

Problems solved by technology

This kind of coating machine simply relies on the light intensity passing through the coating gap to estimate the dry thickness of the electrode film. In fact, it is only a prediction and cannot truly reflect the actual dry thickness of the electrode film. In addition, this through coating The illuminance of the gap is easily affected by the particle size and concentration of the electronic slurry, and the illuminance will be changed incorrectly, resulting in a regulation that is completely unsuitable for the actual situation.

As we all know, the dry thickness of the electrode film is affected by many factors such as the concentration of the slurry, the pressure of the slurry on the coating roller (also called the material pressure), and the mechanical properties. The thickness of the electrode film is controlled simply by measuring the coating gap. The dry thickness is not enough to meet the technical requirements

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