Unveiling Impedance Response of Commercial Coin-type Lithium-ion Batteries Exposed to Overcharge and Over-discharge through Equivalent Circuit Modeling

This study investigates the impedance spectroscopy response of commercial coin-type lithium-ion cells under overcharge and over-discharge conditions through equivalent circuit modeling. Electrochemical tests were conducted on battery cells, employing impedance spectroscopy to track variations across various charge states, including overcharge and over-discharge conditions. The impedance data highlighted distinct patterns during normal operation, prompting the application of an anomalous diffusion impedance model. Regression analysis of the model parameters offered valuable insights into the cells' electrochemical performance before and after exposure to overcharge and over-discharge.