Electrochemical measurements are essential for understanding the characteristics of battery cells, which enables the development of batteries with longer cycle lives and more efficient charge and discharge mechanisms. The electrochemical tests used for analyzing battery capacity, performance, and lifetime are typically carried out using a battery cycler with multiple measurement channels to boost throughput. Battery cycler technologies use repetitions of charge and discharge cycles under controlled conditions to provide information about how the cells behave over time. Battery cycling protocols vary based on the desired output data, but experiments can include open circuit potential (OCP), cyclic voltammetry (CV), chronopotentiometry (CP), and additional, more complex methods such as Electrochemical Impedance Spectroscopy (EIS).
Impedance measurements in battery development
Impedance measurements add an additional layer of quantifying device performance. This non-destructive technique allows for investigation into the degradation mechanisms of batteries while minimizing downtime. It is expected that all batteries will undergo a reduction in performance and an increase in measured impedance as they are cycled over time, which makes impedance measurements an important tool for monitoring battery health. As the battery degrades, understanding the various degradation pathways related to each internal component of the battery empowers scientists with the data they need to optimize the materials. The impedance-based analysis of internal reactions provides information about the anode, cathode, and separator materials, as well as diffusion and different states of charge.
Predictive modeling for battery performance and efficiency
By fitting the impedance data to an equivalent circuit model, the results can be plotted as a function of the state of charge and/or cycle number. The model can be used to simulate the behavior of the battery under different conditions and in different systems to predict its performance and efficiency. This information is critical for identifying sources of resistance in the battery and guiding the process of optimizing the battery’s design.
Factors to consider while choosing a Battery cycler
When choosing a battery cycler for your lab, it is important to consider:
- The type of battery device being measured
- The available measurement modes
- The number of channels needed
- The software features
Ivium Technologies Battery Cyclers
Ivium Technologies designs modular battery cyclers that offer full experimental flexibility with integrated EIS on every channel. By factory-integrating the necessary hardware for simultaneous impedance measurements, the signal path length is shortened, ensuring minimal noise degradation or other effects at high frequency that cables can introduce. These battery-testing systems are designed by electrochemists, for electrochemists and run on the easy-to-use, and feature rich CycliScan tool in the IviumSoft software, which helps users build automated battery cycling protocols, designate specific datasets for later analysis, and choose each mode, parameter, limit, and impedance step in the experiment to assist with Design of Experiments (DOE). For data analysis, the Ivilab program is a powerful tool for analyzing charge/discharge and impedance data. It allows you to visualize data in various ways and extract meaningful information and provides a better understanding of how to improve the battery being tested.
To learn more about our battery cyclers and the benefits of simultaneous impedance measurements on every channel, watch our webinar: Empowering Battery Testing with Ivium Technologies – Nanoscience Instruments