The performance, safety, and reliability of lithium-ion (Li-ion) batteries are heavily influenced by the mechanical properties of their constituent materials. As battery technologies advance to meet the growing demands for higher energy densities and diverse applications—including electric vehicles, portable electronics, and renewable energy storage—understanding the micromechanical behaviour of key battery components is essential. This study employs advanced nanoindentation techniques to investigate the mechanical properties of critical materials, focusing on cathode and anode active materials, which play a pivotal role in the durability and safety of lithium-ion battery packs.
Nanoindentation enables high-resolution characterization of mechanical properties, including hardness, elastic modulus, and viscoelastic behavior, facilitating precise evaluation of localized mechanical responses. In this study, cathode and anode samples were extracted from a prismatic battery cell. The samples were prepared by sequential washing and drying before being affixed to a nanoindentation sample holder. Subsequently, the mechanical properties of the cathode and anode active materials were analyzed through a matrix-based nanoindentation approach. Each individual measurement was evaluated using the Oliver-Pharr method, a standard technique in nanoindentation, to determine the elastic modulus and hardness at each measurement point. The nanoindentation parameters were optimized to ensure that the indentation imprint size corresponded to the characteristic dimensions of the cathode and anode particles.
The results indicate significant heterogeneity in the elastic modulus and hardness of both cathode and anode active materials. Notably, the cathode material exhibits a higher elastic modulus and hardness compared to the anode material.
These findings underscore the critical influence of microstructural properties on the mechanical behavior of lithium-ion battery electrode materials. Future research should focus on elucidating the relationship between mechanical properties, electrochemical performance, and degradation mechanisms to advance the understanding and optimization of battery materials.