Session: 09-03-01: Advanced Electrochemical Energy Materials: Characterization, Modeling, and Theoretical Analysis

Paper Number: 165655

Charge-Discharge Cycle Experiment and Mechanical Damage of Electrode Materials in Lithium-Ion Batteries (LiBs) 

For the development of lithium-ion batteries (LiBs), high energy density, durability (high cycle of charge-discharge) and safety are required. The battery is a layered structure, which consists of a cathode, separator, and anode, with each layer filled with electrolyte. The electrode has a layered structure consisting of a composite of a current-collecting foil layer made of metallic foil, active material particles, and a binder that bonds them together. Active material is important for degradation of battery performance due to cyclic charging-discharging. The mechanical properties of the electrode materials are also changed due to cyclic charging-discharging. One example is the solidification of the electrolyte solution and the formation of an interface layer (SEI: Solid Electrolyte Interface). The SEI layer is formed to cover the anode electrode surface by organic substances (ethylene carbonate, etc.) decomposed in the electrolyte solution and electrons transferred to the anode electrode. In addition, the insertion and desorption reactions of Li ions cause significant expansion and contraction of the active material, which may damage the surrounding binder that plays a big role in the strength of the active material layer. This results in mechanical degradation. On the other hand, on the cathode side, the reaction between the active material and the electrolyte has been reported to cause the formation of CEI. However, few studies have clarified the relationship between charge-discharge degradation and mechanical property degradation. Since mechanical degradation, damage, or delamination of electrode materials can cause accidents such as battery explosion or fire, it is important from the standpoint of battery safety to clarify the mechanism of mechanical property changes caused by cyclic charging and discharging. This study aims to clarify the correlation between the percentage of capacity decrease after charging/discharging and the mechanical properties of each electrode by using SOH (State of Health) to evaluate the degree of degradation of the battery in relation to charging/discharging.

References

Yuzuki Kawashima, Kazuma Ogata, Yuto Shibayama, Aoi Takagi, Akio Yonezu, Jun Xu, Detailed Computational Modeling of Crack Patterns of Silicon-based Anode Sheet in Lithium-ion Batteries Upon Mechanical Stress, Energy Materials and Devices, 2025, 3, 9370054 (10 pages)

Kazuma Ogata, Yuto Kasuya, Xiang Gao, Yuto Shibayama, Aoi Takagi, Akio Yonezu, Jun Xu, Adhesion Strength of an Active Material Layer/Cu Foil Interface in Silicon-Based Anodes, ACS Applied Materials & Interfaces, 16(14), 2024, pp.17692-17700

Kazuma Ogata, Wenxia Tan, Yoshinori Takano, Akio Yonezu, Jun Xu, Mechanical Characterization and Modeling of Microstructural Deformation of Si Anode Sheet, Journal of Power Sources, Volume 580, 1 October 2023, 233442.

Presenting Author: Yuzuki Kawashima Chuo university

Presenting Author Biography: Graduate student at Chuo University

Authors:

Yuzuki Kawashima Chuo university
Daisuke Sumiya Chuo univesity
Akio Yonezu Chuo University