Xiaojun Tan, Sun Yat-sen University, China, is a Professor and leads the Research Center of New Energy Vehicles at the School of Intelligent Systems Engineering, Sun Yat-sen University. He has nearly two decades' research experience in battery modeling, testing and diagnoses, and has spearheaded many industry partnerships.

Andrea Vezzini, Bern University of Applied Sciences, Switzerland is a Professor with more than two decades' experience in battery systems research and development. He leads the Energy Storage Research Centre (ESReC) at Bern University of Applied Sciences and has been involved through several spin-offs in the product development of customized battery system solutions for the industrial and automotive market.

Yuqian Fan, received his PhD. in Intelligent Transportation Engineering from Sun Yat-sen University, China. His research interests include intelligent control and optimization design for power battery systems, battery thermal management and thermal safety, and battery state of health prediction.

Neeta Khare, is a Director with Iveco Group. Dr. Khare acquired her doctoral degree in Intelligent Battery Monitoring from Banasthali University, India. Her core expertise is in aging algorithms of battery/ cell using AI and adaptive algorithms, Battery Pack, Battery Management System (BMS) development, and more.

You Xu, is an Associate Professor at Guangdong Polytechnic Normal University, China, where he has been engaged in power battery system, precision reverse equipment. Dr. You received his PhD. from Sun Yat-sen University. He has authored over 20 scientific publications, and his research interests include battery management for electrical vehicles.

Liangliang Wei, is an Associate Professor in Control Science and Engineering at Sun Yat-Sen University, China. Dr. Wei has authored over 20 scientific publications and received his PhD. in Electrical Engineering from the Wuhan University, China.

Preface xiii

About the Authors xv

Part I Introduction 1

1 Why Does a Battery Need a BMS? 3

1.1 General Introduction to a BMS 3

1.2 Example of a BMS in a Real System 5

1.3 System Failures Due to the Absence of a BMS 7

2 General Requirements (Functions and Features) 11

2.1 Basic Functions of a BMS 11

2.2 Topological Structure of a BMS 16

3 General Procedure of the BMS Design 19

3.1 Universal Battery Management System and Customized Battery Management System 19

3.2 General Development Flow of the Power Battery Management System 21

Part II Li-Ion Batteries 27

4 Introduction to Li-Ion Batteries 29

4.1 Components of Li-Ion Batteries: Electrodes, Electrolytes, Separators, and Cell Packing 29

4.2 Li-Ion Electrode Manufacturing 31

4.3 Cell Assembly in an Li-Ion Battery 32

4.4 Safety and Cost Prediction 33

5 Schemes of Battery Testing 37

5.1 Battery Tests for BMS Development 37

5.2 Capacity and the Charge and Discharge Rate Test 41

5.3 Discharge Rate Characteristic Test 44

5.4 Charge and Discharge Equilibrium Potential Curves and Equivalent Internal Resistance Tests 46

5.5 Battery Cycle Test 49

5.6 Phased Evaluation of the Cycle Process 58

6 Test Results and Analysis 67

6.1 Characteristic Test Results and Their Analysis 67

6.2 Degradation Test and Analysis 80

7 Battery Modeling 101

7.1 Battery Modeling for BMS 101

7.2 Common Battery Models and Their Deficiencies 102

7.3 External Characteristics of the Li-Ion Power Battery and Their Analysis 105

7.4 A Power Battery Model Based on a Three-Order RC Network 110

7.5 Model Parameterization and Its Online Identification 117

7.6 Battery Cell Simulation Model 124

Part III Functions of BMS 133

8 Battery Monitoring 135

8.1 Discussion on Real Time and Synchronization 135

8.2 Battery Voltage Monitoring 139

8.3 Battery Current Monitoring 145

8.4 Temperature Monitoring 149

9 SoC Estimation of a Battery 153

9.1 Different Understandings of the SoC Definition 153

9.2 Classical Estimation Methods 158

9.3 Difficulty in an SoC Estimation 162

9.4 Actual Problems to Be Considered During an SoC Estimation 166

9.5 Estimation Method Based on the Battery Model and the Extended Kalman Filter 169

9.6 Error Spectrum of the SoC Estimation Based on the EKF 177

10 Charge Control 193

10.1 Introduction 193

10.2 Charging Power Categories 196

10.3 Charge Control Methods 198

10.4 Effect of Charge Control on Battery Performance 203

10.5 Charging Circuits 204

10.6 Infrastructure Development and Challenges 209

10.7 Isolation and Safety Requirement for EC Chargers 211

11 Balancing/Balancing Control 213

11.1 Balancing Control Management and Its Significance 213

11.2 Classification of Balancing Control Management 218

11.3 Review and Analysis of Active Balancing Technologies 221

11.4 Balancing Strategy Study 226

11.5 Two Active Balancing Control Strategies 234

11.6 Evaluation and Comparison of Balancing Control Strategies 245

12 State of Health (SoH) Estimation of a Battery 257

12.1 Definition and Indices/Parameters of SoH 257

12.2 Modeling of Battery Degradation (Aging) and SoH Estimation 265

12.3 Battery Degradation Diagnosis for EVs 278

13 Communication Interface for BMS 291

13.1 BMS Communication Bus and Protocols 293

13.2 Higher-Layer Communication Protocols 298

13.3 A Case Study: Universal CiA EnergyBus for a Low-Emission Vehicle (LEV) 299

14 Battery Lifecycle Information Management 301

14.1 Data Type of Power Battery 301

14.2 Vehicle Instrument Data Display 302

14.3 Battery Data Transmission Mode 306

14.4 Information Concerning a Full-Power Battery Lifecycle 311

14.5 Storage and Analysis of Historical Information of a Battery 316

14.6 Battery Detection System Based on a Mobile Terminal 320

Part IV Case Studies 327

15 BMS for an E-Bike 329

15.1 Balancing 329

15.2 Battery Pack Design for an E-Bike 331

15.3 Methodology 333

15.4 Active Balancing Solutions 337

15.5 Test Results 341

15.6 Possibility with Active Balancing 349

15.7 Results and Evaluation 349

16 BMS for a Fork-Lift 353

16.1 Lithium-Iron-Phosphate Batteries for Fork-Lifts 353

16.2 Battery Management Systems for Fork-Lifts 355

16.3 The LIONIC Battery System for Truck Applications 356

16.4 Application 357

16.5 The Usable Energy Li-Ion Traction Batteries 359

17 BMS for a Minibus 363

17.1 Internal Resistance Analysis of a Power Battery System and Discharging Strategy Research of Vehicles 361

17.2 Consistency Evaluation Research of a Power Battery System 377

17.3 Safety Management and Protection of a Power Battery System 386

Index 389