An Electrochemical/Thermodynamic Analytical Model for Hard-Pack Lithium-Ion Batteries in Engineering Education

Abstract

Modeling lithium-ion battery states plays a crucial role in supporting engineering education, yet applying existing models in the classroom poses challenges. This paper presents an electrochemical/thermodynamic analytical model with 19 parameters for hard-pack lithium-ion batteries, providing efficient and compact MATLAB code as an instructional tool for engineering education. The paper elucidates the mechanisms of electrochemical/thermodynamic behavior evolution in lithium-ion batteries under thermal abuse and develops a state evaluation model based on ordinary differential equations. The highly nonlinear dynamic problem is discretized into a series of static problems, which are solved using the Levenberg–Marquardt algorithm. The MATLAB program is applied to prismatic and cylindrical lithium-ion batteries, yielding critical venting points and state evolution curves, such as temperature, pressure, gas production, heat generation rate, and reaction rate. The comprehensive results vividly demonstrate the evolution of electrochemical and thermodynamic behavior in lithium-ion batteries, aiding students in grasping complex concepts within the course. The modeling and solution process, along with the discussion of algorithm parameters, are expected to enhance students' programming skills and engineering thinking. The proposed algorithm demonstrates second-level efficiency and good convergence, highlighting its potential for classroom applications.