Identification and quantification of ageing mechanisms in Lithium-ion batteries using the EIS technique

Investigating the Effects of Mechanical Damage on Electrical Response of Li-Ion Pouch Cells

“…Electrochemical impedance spectroscopy data for all EIS measurements is fit to the proposed ECM using the simplex method. The simplex method as previously stated is an optimization algorithm, that uses functional evaluation to settle at a local minimum [32]. The initial value Warburg diffusion element was estimated using (17) and (10), where the diffusion coefficient is 2e -15 m 2 /mol.…”

“…The equivalent circuit model for this study can be seen in Figure 3, it consists of passive elements to replicate a complex non-linear electrical circuit. This ECM is proposed in [25], [32]. Each element in the ECM can be attributed to one of five electrochemical phenomena occurring in the cell: loss of conductivity, solid electrolyte interface formation, charge transfer resistance, double layer capacitance and finite diffusion.…”

Study on degradation behavior of commercial 18650 LiAlNiCoO2cells in over‐charge conditions

“…Then the increase of charge transfer impedance (R ct ) is also relevant with LLI. 1,20 Since diffusion process is related to morphological changes in the electrode structure, the change of Warburg impedance (R W ) would lead to LAM. Considering the slope of the straight line at low frequency is proportional to the variation of the Warburg impedance, 42 the R W was described by using the slope change of the straight line.…”

“…19 On the basis of Dubarry's research, Carlos et al analyzed the effects of the degradation modes using incremental capacity and differential voltage (IC-DV) analysis and EIS. 20 They then compared IC-DV and EIS on the same data set to evaluate if both techniques provide similar insights into the causes of cell degradation and found both techniques are correlated. 20 The derivative technique of IC looks at the evolution of the increments of capacity (dQ) per increment of voltage (dV).…”

“…20 They then compared IC-DV and EIS on the same data set to evaluate if both techniques provide similar insights into the causes of cell degradation and found both techniques are correlated. 20 The derivative technique of IC looks at the evolution of the increments of capacity (dQ) per increment of voltage (dV). 21 It is believed that such analysis can improve understanding of cell degradation mechanisms and offer different insights into the rate and nature of Li-ion cell.…”