loading page

Incremental Capacity and Voltammetry of Batteries, and Implications for Electrochemical Impedance Spectroscopy
  • +2
  • Christopher J. Dunn,
  • Jonathan B. Scott,
  • Marcus T. Wilson,
  • Michael R. Mucalo,
  • Michael J. Cree
Christopher J. Dunn
The University of Waikato School of Engineering

Corresponding Author:[email protected]

Author Profile
Jonathan B. Scott
The University of Waikato School of Engineering
Author Profile
Marcus T. Wilson
The University of Waikato School of Science
Author Profile
Michael R. Mucalo
The University of Waikato School of Science
Author Profile
Michael J. Cree
The University of Waikato School of Engineering
Author Profile

Abstract

Incremental capacity analysis (ICA), where incremental charge (Q) movements associated with changes in potential are tracked, and cyclic voltammetry (CV), where current response to a linear voltage sweep is recorded, are used to investigate the properties of electrochemical systems. Electrochemical impedance spectroscopy (EIS), on the other hand, is a powerful, non-destructive technique that can be used to determine small-signal AC impedance over a wide frequency range. It is frequently used to design battery equivalent-circuit models. This manuscript explores the relationships between ICA, CV and EIS and demonstrates how sweep rate in CV is related to charging (C) rate in ICA. In addition, it shows the connection between observations linked to rate of charge movement in CV and ICA and intermittent, irregular behavior seen in EIS when performed on a battery. It also explains the use of an additional DC stimulus during EIS to ensure reliability of battery impedance data and to facilitate equivalent-circuit modeling, and suggests a method for obtaining CV-type data from a whole battery without risking its destruction.