Nondestructive measurement method for binder content and performance of lithium-ion battery based on electrode deflection under bending deformation

• Published in: Journal of power sources Vol. 495; p. 229800
• Main Authors: Yamaguchi, Yuhei, Sato, Yasumoto, Kumano, Naomi, Nakano, Hiroyuki
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 31.05.2021
• Subjects: Bending deformation; Binder content; Elastic property; Lithium-ion battery; Nondestructive measurement; Nondestructive measurement; Lithium-ion battery; Binder content; Elastic property; Bending deformation
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2021.229800

To confirm the durability and reliability of lithium-ion batteries, a fundamental study for the development of nondestructive measurement method for binder content and performance of the batteries prior to cell assembly is presented herein. This study focuses on the deflection of the electrode, consisting of a current collector and an electrode film on the current collector. Bending deformation is used as a representative measurement for the binder content because it can easily be induced and measured during the production process of the electrode. The correlation between the binder content and the Young's modulus of the electrode film is characterized via tensile testing. Furthermore, the correlation between the Young's modulus of the electrode film affected by the binder content and the electrode deflection under bending deformation is experimentally confirmed and verified using finite element analysis (FEA). Additionally, it is confirmed that the charge-transfer resistance and discharge capacity retention of the cells assembled with different binder contents vary. Ultimately, it is shown that the binder content, discharge capacity retention, and charge-transfer resistance of the cells with different binder contents can be predicted from electrode deflection prior to cell assembly. •Nondestructive measurement of binder content of electrode based on deformation.•Bending deformation of electrode depends on Young's modulus of the electrode film.•Young's modulus of the electrode film is correlated with binder content.•Correlation between binder content and electrode deflection under bending.•Deflection predicts charge-transfer resistance and discharge capacity retention.