Calibration of Electrochemical Models for Li-ion Battery Cells Using Three-Electrode Testing

Electrochemical models of lithium ion batteries are today a standard tool in the automotive industry for activities related to the computer-aided engineering design, analysis, and optimization of energy storage systems for electrified vehicles. One of the challenges in the development or use of such models is the need of detailed information on the cell and electrode geometry or properties of the electrode and electrolyte materials, which are typically unavailable or difficult to retrieve by end-users. This forces engineers to resort to “hand-tuning” of many physical and geometrical parameters, using standard cell-level characterization tests.

This paper proposes a method to provide information and data on individual electrode performance that can be used to simplify the calibration process for electrochemical models. The proposed approach consists in inserting a reference electrode in commercial-grade Li-ion to obtain real-time data of how the cathode and anode interact with one another during cell operation, rather than resorting to coin cell testing of individual electrode materials.