How to test the adhesion fastness of electrode coating on electrode surface

Abstract: whether the electrode coating is easy to fall off is an important factor affecting the performance and service life of the battery In this paper, 180 degree peel test is used to test the peel strength of the coating on the surface of electrode samples, and the test principle, parameters and application scope of XLW (PC) intelligent electronic tensile testing machine and the test process are introduced, so as to provide reference for how to test the adhesion fastness of electrode coating Key words: electrode coating, adhesion fastness, peeling force value, 180 degree peeling, intelligent electronic tensile testing machine, coating peeling 1 Significance according to different coating materials and electrode types, electrode coating has a variety of functions, such as good electrochemical activation function, improving the oxidation resistance of electrode, etc The firmness of the coating on the electrode surface is an important factor to determine whether the coating can give full play to the above functions If the coating has poor adhesion and even falls off, it will reduce or even lose its activation and oxidation resistance functions, leading to electrode failure and serious loss, greatly reducing the service life of the battery With the promotion and application of battery in the fields of automobile, electric energy storage, mobile communication, new energy energy energy storage power supply, navigation and so on, the service life is more important for the application performance of battery, so we should pay more attention to the detection and research of the adhesion fastness of electrode coating This paper introduces an effective test method for the adhesion of coating Figure 1 example of coated electrode 2 In this paper, the black coated electrode is used as the test sample 3 At present, there is no test method standard related to the adhesion fastness of electrode coating published in China The sample preparation part of this test is carried out according to the relevant ink layer binding fastness part of GB / T 7707-2008 intaglio decoration printing, and the test process is carried out according to GB 8808-1988 soft composite plastic material peeling test method 4 This test uses XLW (PC) intelligent electronic tensile testing machine to test the peel strength of the sample 4.1 test principle this test is to evaluate the adhesion fastness of the coating on the electrode surface by testing the force value required for the adhesive tape to peel the coating off the electrode surface During the test, the test is clamped in the lower clamp, the clamp is fixed, and the free end of the adhesive tape used to paste the coating is fixed in the upper clamp The clamp can move upward according to the set speed, so as to drive the adhesive tape to peel the coating from the electrode surface The force sensor equipped with the upper fixture records the force generated during the stripping process in real time, and the average value of the force value is taken as the stripping force value of the electrode coating Fig 2 XLW (PC) intelligent electronic tensile testing machine 4.2 two kinds of force value sensors with equipment parameters of 500N and 50N can be selected, and the test accuracy is 0.5 level, which is far and away in the industry, effectively ensuring the accuracy of test results; according to relevant standards, the equipment provides 50mm / min, 100mm / min, 150mm / min, 200mm / min, 250mm / min, 300mm / min Seven test speeds of 500 mm / min can be set freely according to the requirements of test standards; 1000 mm The ultra long stroke of the tester can meet the requirements of the testing of materials with ultra large deformation rate; the intelligent configuration of limit protection, overload protection, automatic return and power failure memory can ensure the operation safety of the user; a tester integrates seven independent testing procedures such as stretching, peeling and tearing, which provides the user with a variety of test options 4.3 scope of application (1) the equipment can be used for the test of peel strength, tensile property, breaking force, tensile strength and deformation rate, tear resistance, heat sealing strength, puncture resistance and other indexes of plastic film, composite film, thin film and other materials; it can be used for the puncture of infusion bag cover, soft rubber bottle plug and oral liquid cover/ It can be used to test the unwinding force of adhesive tape, the pressure resistance of plastic bottle, the opening force of combined cover, jelly cup, yoghurt cup cover film and other products and packaging performance (2) The equipment can meet more than 20 domestic and foreign relevant standards such as ISO 37, GB / T 10004, GB 8808, GB / T 1040.1, GB / T 1040.2, GB / T 1040.3, GB / T 1040.4, GB / T 1040.5, QB / T 2358, QB / T 1130, ASTM d882, ASTM D1938, ASTM d3330, etc 5 During the test (1) cut 5 samples with width of 15.0 mm and length of 100 mm from the surface of electrode sample containing coating, and 5 adhesive tapes with width of 15.0 mm and length of at least 250 mm from the adhesive tape meeting the requirements of the standard (2) Five adhesive tapes shall be pasted on five samples respectively, and the width direction of the two shall be fully aligned The samples pasted with adhesive tapes shall be rolled three times by the adhesive tape roller press, and placed for 10 minutes (3) Parameter information such as sample name, test speed, invalid head length and invalid tail length shall be set on the control software of the equipment (4) Install the free end of the adhesive tape and the sample in the upper and lower clamps of the equipment, click the test option, and the test starts The upper fixture moves upward to make the adhesive tape with coating peel off from the sample electrode After the test, the equipment displays the test results Test the remaining 4 samples according to the loading test process 6 Test results the test results of the five samples tested in this test are 0.831 n / 15mm, 0.806 n / 15mm, 0.846 n / 15mm, 0.811 n / 15mm and 0.795 n / 15mm respectively, so the force required for the coating to peel off the electrode surface is 0.818 n / 15mm 7 Conclusion the adhesion fastness of the coating on the electrode surface is an important factor affecting the service life of the battery In this paper, the 180 degree peel test method is used to measure the force required to peel the coating off the electrode surface, and to characterize the adhesion fastness of the coating on the electrode surface The test is simple, the equipment is easy to operate, and the test results are reliable In order to better simulate the actual application environment of the electrode, the prepared sample can also be placed in the high temperature environment for a period of time for testing according to the actual situation Ji'nan Languang mechanical and Electrical Technology Co., Ltd is a high-tech enterprise specializing in the R & D and production of packaging testing equipment and packaging testing services The more you understand, the more you trust! 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