[Analysis Case] Evaluation of Si Anode in Lithium-Ion Secondary Batteries

It is possible to evaluate the structure of the Si anode after charging through sample cooling.

Si is one of the candidates for high-capacity negative electrode active materials, but it is said to suffer from severe cycle degradation due to very large volume changes during charge and discharge. In this study, to confirm the state of the Si negative electrode after charging, we disassembled it under a controlled atmosphere environment and performed cooling FIB processing, followed by observing the cross-sectional shape using SEM. When observing the cross-section at room temperature, significant damage such as film contraction, roughness of the observation surface, and pore formation was observed. In contrast, by conducting the observation while cooling, we were able to suppress the alteration of the Si negative electrode and evaluate the original shape of the sample.

Contract AnalysisContract measurement