Page 21 - Handbook of Battery Materials

XX Contents

19.6.1.1 Direct-Current (DC) Measurements 681
19.6.1.2 Impedance Analysis 682
19.6.1.3 Determination of the Activation Energy 683
19.6.2 Partial Electronic Conductivity 683
19.6.2.1 Determination of the Transference Number 685
19.6.2.2 The Hebb–Wagner Method 685
19.6.2.3 Mobility of Electrons and Holes 686
19.6.2.4 Concentration of Electrons and Holes 686
19.6.3 Stability Window 688
19.6.4 Determination of the Ionics Conduction Mechanism and Related
Types of Defects 689
Acknowledgment 690
References 690
Further Reading 691
20 Separators for Lithium-Ion Batteries 693
Robert Spotnitz
20.1 Introduction 693
20.2 Market 694
20.3 How a Battery Separator Is Used in Cell Fabrication 697
20.4 Microporous Separator Materials 700
20.5 Gel Electrolyte Separators 707
20.6 Polymer Electrolytes 708
20.7 Characterization of Separators 708
20.8 Mathematical Modeling of Separators 712
20.9 Conclusions 714
References 714

21 Materials for High-Temperature Batteries 719
H. B¨ohm
21.1 Introduction 719
21.2 The ZEBRA System 720
21.2.1 The ZEBRA Cell 720
21.2.2 Properties of ZEBRA Cells 721
21.2.3 Internal Resistance of ZEBRA Cells 723
21.2.4 The ZEBRA Battery 726
21.3 The Sodium/Sulfur Battery 728
21.3.1 The Na–S System 728
21.3.2 The Na/S Cell 729
21.3.3 The Na/S Battery 731
21.3.4 Corrosion-Resistant Materials for Sodium/Sulfur Cells 733
21.3.4.1 Glass Seal 733
21.3.4.2 Cathode and Anode Seal 733
21.3.4.3 Current Collector for the Sulfur Electrode 734
21.4 Components for High-Temperature Batteries 735