18650 lityum-iyon ve 6HR61 nikel-metal hidrit tekrar şarj edilebilir pillerinin elektrokimyasal empedans analizi

Abstract

Highlights:Graphical/Tabular Abstract  Comparison of the impedance response of batteries  Novel process model for impedance response of rechargeable batteries  Interpretation of battery dynamics by an equivalent circuit analysis Figure A. The graph on the left handside is the Nyquist plot of 18650 lithium-ion battery cell at the potential of 3.5 volts presenting impedance (EIS) data and Kramers-Kronig (K-K) fit with the indications and explanations of electrochemical properties of the cell. The picture on the top right shows the experimental setup. The scheme on the bottom right represents the equivalent circuit for rechargeable batteries; i.e., commercially obtained 18650 lithium-ion and 6HR61 nickel-metal hydride batteries.Purpose: The objective of this work is to analyze and model impedance of widely used rechargeable batteries which are 18650 cylindrical lithium-ion battery and 6HR61 nickel-metal hydride battery pack. Theory and Methods:The rechargeable batteries were charged or discharged by using a potentiostat connected to a desktop computer. The impedance analysis of the batteries was performed at the same conditions; such as, cell potential, frequency range, temperature, and ac perturbation. The impedance responses were interpreted through equivalent circuit modeling. Results:The impedance of nickel-metal hydride cell was much greater than that of lithium-ion cell. The fit of the developed model was successful for both batteries. The regressed parameters which are significant for energy storage systems were extracted from the obtained equivalent circuit elements. Conclusion:It was concluded that lithium-ion battery had many advantages compared to nickel-metal hydride battery in terms of capacity and performance. The used electrochemical impedance spectroscopy technique and the resulting model could be a potential candidate method for the improvement of non-commercial batteries and the ability to meet the energy needs.

Analysis of electrochemical impedance spectroscopy response for commercial lithium-ion batteries: modeling of equivalent circuit elements

“…The diffusion of ions to the electrodes was represented by Z w,c . A full description of the mathematical model is provided in Moralı and Erol [7] and will therefore not be duplicated here.…”

“…The orthogonal array obtained the requisite data from the minimal number of experimental runs, and furthermore, it provided good separation of the optimum levels of each parameter for response variables. In this study, the input factors and their levels were selected based on our previous study [7]. The Taguchi design method was used to identify the factors having a significant influence on physically meaningful parameters.…”

“…The power capability of a battery is intimately involved in its impedance characteristics [7]. The impedance of a cell is the potential drop under an alternative current and is related to the frequency and retention of the applied current [8].…”

“…Recent literature shows that there is a significant effort towards improvement of LIB properties to extend their use [6,7,9]. The battery characteristics associated with performance parameters depend on a wide range of factors such as temperature, cell type, cell constituents, applied current, state-of-charge, and cyclic aging [11].…”

“…The developed process model fitted well to the impedance response, suggesting a detailed interpretation of the performance of commercial Li-ion cells. Moralı and Erol recently measured the impedances versus the state-of-charge of the commercial batteries to elucidate how the characteristics of the batteries under different SoCs are related to the alteration in cell parameters [7].…”