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Thermal-Electrochemical Modeling and State of Charge Estimation for Lithium Ion Batteries in Real-Time Applications Thermal-Electrochemical Modeling and State Of THERMAL-ELECTROCHEMICAL MODELING AND STATE OF CHARGE ESTIMATION FOR LITHIUM ION BATTERIES IN REAL-TIME APPLICATIONS THERMAL-ELECTROCHEMICAL MODELING AND STATE OF CHARGE ESTIMATION FOR LITHIUM ION BATTERIES IN REAL-TIME APPLICATIONS BY MOHAMMED FARAG, M.A.Sc., B.Sc. a thesis submitted to the department of Mechanical Engineering and the school of graduate studies of mcmaster university in partial fulfilment of the requirements for the degree of Doctor of Philosophy c Copyright by Mohammed Farag, February 2017 All Rights Reserved DOCTOR OF PHILOSOPHY (2017) McMaster University (Mechanical Engineering) Hamilton, Ontario, Canada TITLE: Thermal-Electrochemical Modeling and State of Charge Estimation for Lithium Ion Batteries in Real-Time Ap- plications AUTHOR: Mohammed Farag M.A.Sc., (Mechanical Engineering) McMaster University, Hamilton, Ontario, Canada SUPERVISOR: Dr. Saeid R. Habibi, Professor Department of Mechanical Engineering NUMBER OF PAGES: xxii, 226 ii I dedicate this work to my wonderful parents. "It is not the critic who counts; not the man who points out how the strong man stumbles, or where the doer of deeds could have done them better. The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood; who strives valiantly; who errs, who comes short again and again, because there is no effort without error and shortcoming; but who does actually strive to do the deeds; who knows great enthusiasms, the great devotions; who spends himself in a worthy cause; who at the best knows in the end the triumph of high achievement, and who at the worst, if he fails, at least fails while daring greatly, so that his place shall never be with those cold and timid souls who neither know victory nor defeat." Theodore Roosevelt iv Permission to use In presenting this thesis in partial fulfillment of the requirements for a Postgraduate degree from McMaster University, I agree that the Libraries of this University may make it freely available for inspection. I further agree that the permission for copying this thesis in any manner, in whole or in part for scholarly purposes, may be granted by the professors who supervised my thesis work or, in their absence, by the Head of the Department or the Faculty Dean in which my thesis work was conducted. It is understood that any copying or publication or use of this thesis or parts thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and McMaster University in any scholarly use which may be made of any material in my thesis. Requests for permission to copy or to make other use of material in this thesis, in whole or part, should be addressed to: Head of the Department of Mechanical Engineering McMaster University Faculty of Engineering 1280 Main Street West Hamilton, Ontario L8S 4L6, Canada. v Abstract In the past decade, automobile manufacturers have gone through the initial adoption phase of electric mobility. The increasing momentum behind electric vehicles (EV) suggests that electrified storage systems will play an important role in electric mo- bility going forward. Lithium ion batteries have become one of the most common solutions for energy storage due to their light weight, high specific energy, low self- discharge rate, and non-memory effect. To fully benefit from a lithium-ion energy storage system and avoid its physical limitations, an accurate battery management system (BMS) is required. One of the key issues for successful BMS implementation is the battery model. A robust, accurate, and high fidelity battery model is required to mimic the battery dynamic behavior in a harsh environment. This dissertation introduces a robust and accurate model-based approach for lithium-ion battery man- agement system. Many strategies for modeling the electrochemical processes in the battery have been proposed in the literature. The proposed models are often highly complex, re- quiring long computational time, large memory allocations, and real-time control. Thus, model-order reduction and minimization of the CPU run-time while main- taining the model accuracy are critical requirements for real-time implementation of lithium-ion electrochemical battery models. In this dissertation, different modeling vi techniques are developed. The proposed models reduce the model complexity while maintaining the accuracy. The thermal management of the lithium ion batteries is another important consid- eration for a successful BMS. Operating the battery pack outside the recommended operating conditions could result in unsafe operating conditions with undesirable con- sequences. In order to keep the battery within its safe operating range, the tempera- ture of the cell core must be monitored and controlled. The dissertation implements a real-time electrochemical, thermal model for large prismatic cells used in electric ve- hicles' energy storage systems. The presented model accurately predicts the battery's core temperature and terminal voltage. vii Acknowledgements Firstly, I would like to express my sincere gratitude to my advisor Prof. Saeid Habibi for the continuous supervision of my Ph.D. study, for his patience, motivation, and immense knowledge. His guidance helped me in all the time of research. Besides my advisor, I would like to thank my thesis committee: Prof. A. Emadi, Prof. G. Goward, and Prof. F. Yan, for their insightful comments and encouragement. Financial support provided by the BMW AG, the Natural Sciences and Engi- neering Research Council of Canada (NSERC), the School of Graduate Studies, the Department of Mechanical Engineering, and the Ontario Government's Graduate Scholarship Program is acknowledged. My sincere thanks also go to my BMW colleagues in Munich, Germany, who provided me an opportunity to join their team, and provided access to the laboratory data and research facilities. I would like to thank all my friends, A. El-Mazariky and L. Schumann for their continuous support, encouragement and for all the fun we had in the past few years. Also, without whom this thesis would have been completed a year earlier. Last but not the least, I would like to thank my family: my parents, my brother, and my sister for their endless love, encouragement, and absolute confidence in me throughout my life. viii Publications and Patents In compliance with the regulations of McMaster University, this dissertation is assem- bled as a sandwich thesis composed of four journal articles. These articles represent the independent work of the author of this dissertation. The research also resulted in two patents. The publications and patents are as follows. [1] International Patent - filled in June 28, 2016 and received an application no. PCT/EP2016/065003. Authors: Mohammed Farag (McMaster Univeristy), Benno Schweiger (BMW AG), and Saeid Habibi (McMaster Univeristy). Title: Method and device for estimating a voltage of a battery [2] International Patent - filled in June 28, 2016 and received an application no. PCT/EP2016/064998. Authors: Mohammed Farag (McMaster Univeristy), Edwin Knobbe (BMW AG), Benno Schweiger (BMW AG), Matthias Fleckenstein (BMW AG), and Saeid Habibi (McMaster Univeristy). Title: Method and device for estimating the state of charge of a battery ix [3] Journal article - submitted and accepted by the Journal of Power Sources Mohammed Farag, Matthias Fleckenstein, and Saeid Habibi. Title: Continuous piecewise-linear, reduced-order electrochemical model for lithium- ion batteries in real-time applications. http://dx.doi.org/10.1016/j.jpowsour. 2016.12.044 [4] Journal article - Submitted in December 2016 and under revision by the Journal of Power Sources Mohammed Farag, Haitham Sweity, Matthias Fleckenstein, and Saeid Habibi. Title: Combined reduced-order electrochemical, heat generation, and thermal model for large prismatic lithium-ion batteries in real-time applications. [5] Journal article - submitted in March 2017 to the IEEE Journal of Emerging and Selected Topics in Power Electronics Mohammed Farag and Saeid Habibi. Title: A critical comparative review of battery modeling categories and state of charge estimation strategies for real-time applications. [6] Journal article - Accepted by the International Journal of Chemical, Molecular, Nuclear, Materials and Metallurgical Engineering. Mohammed Farag, Mina Attari, Andrew Gadsden, and Saeid Habibi. Title: Li-ion battery state of charge estimation using one state hysteresis model with nonlinear estimation strategies. http://waset.org/publications/10006626 x Table of Contents Permission to usev Abstract vi Acknowledgements viii Publications and Patents ix Table of Contents xi List of Tables xvii List of Figures xix 1 Introduction1 1.1 Thesis Motivation.............................1 1.2 Thesis contributions and novelty.....................2 1.3 Thesis Outline...............................4 2 Literature Review7 2.1 Introduction................................7 xi 2.2 Background................................9 2.2.1 Operating principles of Li-ion batteries.............9 2.2.2 Battery terminology....................... 11 2.3 Battery management system....................... 12 2.4 Battery models.............................. 13 2.4.1 Ideal battery models....................... 13 2.4.2 Behavioral or Black-box battery models............ 14 2.4.3 Equivalent circuit battery models................ 19 2.4.4 Electrochemical battery models................. 25 2.5 Battery thermal managament...................... 28 2.5.1 Heat generation
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