Electrochemical Cell Modeling
Simscape™ Battery™ includes Simscape blocks or dynamic models of battery cells and fuel cells. These blocks allow you to emulate the time-based or frequency-based response of your cells for design and verification. Use these blocks as fundamental elements to start building your system-level models such as battery modules, battery packs, or fuel cell stack. By default, these fundamental blocks include the most basic electrical dynamics required for fast-running simulation, but they can also include thermal effects and more complex electrical parameter dependencies.
Equivalent circuit models (ECM) approximate the dynamic behavior of an electrochemical cell, such as the voltage response over time, by using a collection of electrical circuit elements, including resistors, capacitors, and inductors connected in a specific circuit topology. An ECM is an analogy to a real electrochemical system. ECMs have faster simulation times but lower model fidelity and accuracy.
Electrochemical models provide a detailed representation of the physical and chemical processes inside the battery. These models can represent the charge and mass transfer, reaction kinetics, and thermodynamics. The models are computationally intensive and are more challenging to parameterize.
Simscape Blocks
Topics
- Model PEM Fuel Cell with Membrane Water Dynamics
This example shows how to model a proton-exchange membrane (PEM) fuel cell stack with a custom Simscape™ block. (Since R2024b)
- Parameterize Entropic Coefficient with Measurement Protocol and Data Analysis
This example shows what experiments to conduct and how to analyze the resulting experimental data for parameterizing the entropic coefficient. (Since R2024a)
Featured Examples
Analyze Battery Spatial Temperature Variation During Fast Charge
How the temperature gradient over the cell surface varies during the fast charging of a battery. Fast charging is one of the key enablers for the adoption of battery electric vehicles. Fast charging pushes a considerable amount of current inside the battery. This process produces a lot of heat. It is important to understand how temperatures spatially vary in a battery and how this affects its long term warranty. Typically, to ensure a good battery life with uniform degradation, the temperature gradient over the cell surface should not exceed around five or six degrees centigrade. This example uses Simscape™ Battery™ to model the cell electrical dynamics and the Partial Differential Equation Toolbox™ to generate the reduced order model (ROM) that describes the battery 3-D thermal model. This example uses a 50 ampere-hour battery (Valence:U27_36XP) and charges it for 10 minutes from an initial state of charge (SOC) of 15%. Then, the example analyzes the maximum gradient in the cell temperature.
Analyze Performance of Vanadium Redox Flow Battery
Model a vanadium redox flow battery (VRFB), calculate the state of charge (SOC), and assess the impact of electrolyte flow rate on the performance of the battery.
Examine Effects of Diffusion Coefficient and Volume Fraction on Battery Terminal Voltage
How the diffusion coefficient and the volume fraction of the electrode active material of a Battery Single Particle block affect the battery terminal voltage.
Model Battery Cycling Aging
Simulate the capacity cycling aging of a battery. Battery aging is a critical factor that affects the performance and lifespan of energy storage systems. As batteries undergo charge and discharge cycles, their components degrade, which leads to a gradual decline in capacity and efficiency. Solid electrolyte interface (SEI), lithium plating, and other side reactions are the main cause of degradation in lithium-ion batteries.
Model Voltage Hysteresis in Battery
Simulate the voltage hysteresis phenomena in rechargeable batteries by using the Battery Equivalent Circuit block. The open-circuit voltage (OCV) is the difference in measured voltage between the battery terminals when the current flow is equal to zero. The OCV is the electromotive force or the rest potential. For rechargeable or secondary batteries such as lithium-ion batteries, the OCV at a given state of charge and temperature state depends on whether you previously charged or discharged the battery. In lithium-ion cells with conventional intercalation electrodes, this discrepancy is typically explained by the presence of different solid phases in the electrode active material, reaction path hysteresis, and related thermodynamic effects. The lithiation and delithiation of an electrode active material during the charge and discharge processes often produce different electrode solid phases at different states of charge depending on battery chemistry.
