Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Electrical Engineering and Computer Science

First Advisor

Qiquan Qia

Second Advisor

Huitian Lu


1D-electrochemical model, Charge-discharge behavior, Coulumb's counting, Kinetic Monte Carlo, SOC, SOH, Solid-Electrolyte Interface layer


The accurate model on the growth of Solid-Electrolyte Interface (SEI) layer of Lithiumion batteries is used to study the capacity fade, ageing, and cycling life and provides significant information to ensure the battery safety. In this work, the model for SEI layer dynamics is developed using the Kinetic Monte Carlo approach, in which four major dynamical processes including adsorption, absorption, diffusion, and passivation are described by their individual rates, and determined from chemical and physical properties of materials used in the battery. Total cycle numbers to be simulated determine the number of Kinetic Monte Carlo steps. The formation of a passive SEI layer with variable thickness was simulated based on a mathematical model of SEI dynamics. The interfacial resistance of every cycle was calculated with the varying coverage and thickness of SEI layer. The simulation results were found consistent with the literature where thickness increased proportionally to the square root of the time (cycle). The interfacial resistance obtained from the simulation was used in the 1D- electrochemical model, to predict the chargedischarge behavior of the battery with the varying resistance. The State of Charge (SOC) was also calculated using Coulomb’s counting and impedance spectroscopy method, whereas the State of Health (SOH) was determined through the measurement of internal resistance and capacity. After the coupling of SEI layer model to the 1D electrochemical model, the results obtained from the simulation were validated with experimental results.

Library of Congress Subject Headings

Lithium ion batteries -- Materials.
Electric capacity.
Monte Carlo method.


Includes bibliographical references (pages 97-101).



Number of Pages



South Dakota State University



Rights Statement

In Copyright