Energy Storage Science and Technology ›› 2024, Vol. 13 ›› Issue (5): 1699-1706.doi: 10.19799/j.cnki.2095-4239.2023.0954

• Energy Storage Test: Methods and Evaluation • Previous Articles     Next Articles

Mechanical behavior and structure of lithium-ion battery electrode calendering process

Xinbing XIE1(), Kaiyue YANG1, Xiaozhong DU1,2()   

  1. 1.School of Mechanical Engineering, Taiyuan University of Science and Technology
    2.School of Energy and Materials Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, Shanxi, China
  • Received:2023-12-27 Revised:2024-01-11 Online:2024-05-28 Published:2024-05-28
  • Contact: Xiaozhong DU E-mail:xinbing_x@126.com;xiaozhong_d@163.com

Abstract:

Calendering is a crucial step in the electrode preparation process for lithium-ion batteries, significantly impacting the battery's consistency and safety. Given that the electrode is a composite material comprising a current collector (metal) and a coating (nonmetal), the complexity of the calendering deformation mechanism is heightened. In this study, we employed the discrete element method (DEM) model to characterize the coating component of the cathode electrode in a lithium battery, simulating the electrode calendering process numerically. Cathode electrodes were prepared, and experiments with varying calendering degrees were conducted. The congruence between the numerical simulations and experimental outcomes validates the model's accuracy. This research delves into the electrode's morphological evolution throughout the calendering process, unveiling the fundamental nature of calendering deformation. It also quantifies the load at the interface between the coating and the current collector during calendering, providing an in-depth interface analysis. The findings indicate that the DEM model can effectively simulate the microstructural evolution and actual mechanical behavior of the electrode. As the rolling reduction increases, the maximum stress on the current collector exhibits a linear rising trend. The enhanced compactness among the active particles in the coating is identified as the primary cause of calendering deformation. Some active particles in the coating become embedded in the current collector's surface, causing noticeable plastic deformation and stress concentration. This investigation offers innovative research perspectives and valuable insights for further exploration of the electrode calendering process.

Key words: lithium-ion battery, electrode calendaring, discrete element method

CLC Number: