The document discusses the 4RC model of Li-ion batteries, which uses four resistor-capacitor elements to accurately represent a battery's internal behavior and dynamic performance. It provides advantages over simpler models by capturing both steady-state and transient responses. The 4RC model sees applications in battery management systems, electric vehicle design, and renewable energy storage due to its improved accuracy in predicting battery state and performance. However, its complexity requires accurate estimation of resistor and capacitor parameter values.

1. Equivalent Circuit 4RC
Model of Li-ion Battery
In this presentation, we'll discuss the advantages and uses of the 4RC
model of Li-ion batteries, including its basic components, working
principles, and limitations.
by Vandana MS

2. Importance of Accurate Battery Models
1 Battery management systems
Control the charging and discharging
process of batteries to ensure safe and
effective operation.
2 Electric vehicle design
Optimize battery performance for
maximum range and durability.
3 Renewable energy systems
Store and deliver energy from solar and
wind power more efficiently.
4 Consumer electronics
Extend battery life and improve overall
device performance.

3. Overview of Li-ion Battery Equivalent
Circuits
Single RC Model
Simplest equivalent circuit,
consisting of a single resistor
and capacitor element. Good
for steady-state behavior but
limited in capturing transient
responses.
Dual Polarization
Model
Adds two additional elements
to capture polarization effects.
More accurate than single RC
model but adds complexity.
4RC Model
Includes four resistor-
capacitor elements to capture
the battery's internal behavior.
Offers the most accurate
representation of dynamic
battery performance.

4. Basic Components of 4RC Model
Resistor Elements
Represent the I-R voltage loss within the cell. The
4RC model includes four resistor elements.
Capacitor Elements
Represent the electrochemical reactions of
charge transfer within the cell. The 4RC model
includes four capacitor elements.

5. Working Principle of 4RC Model
1 Current-Voltage Relationship
Current flowing through the resistors and capacitors results in voltage changes
between the nodes.
2 RC Time Constants
Time constants are defined by the individual R and C values, and determine how
quickly the voltage changes in response to current changes.
3 Complete Behavior
The combination of all four RC elements allows for an accurate representation of both
the steady-state and transient behaviors of a cell.

6. Advantages of Using 4RC Model
Improved Accuracy
Allows for a more accurate prediction of
dynamic battery behavior and performance.
Capturing Transient Responses
Enables the model to capture the cell's
transient behavior, such as during a current
or temperature change.

7. Limitations and Considerations
1 Model Complexity
The 4RC model is more complex than other equivalent circuits, requiring accurate
parameter estimation.
2 Parameter Estimation
Accurate estimation of R and C values is crucial for reliable modeling. Different
models will require different approaches to parameter estimation.

8. Applications and Uses of 4RC Model
Battery Management System Design
The 4RC model can be used in the design and
development of advanced battery management
systems.
Battery State Estimation
Accurate battery models are essential for state
estimation and prediction of battery
performance.

9. Conclusion
Recap of 4RC Model Advantages and
Uses
The 4RC model provides an accurate means of
predicting battery performance in a variety of
applications, making it an essential tool for battery
researchers and engineers.
Importance of Accurate Battery
Modeling
Accurate battery models are essential in
designing efficient and reliable battery-based
systems, from electric cars to solar energy
storage.