Lithium Ion Rechargeable Batteries E-Book

• Herausgeber: Wiley-VCH
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 582

Veröffentlichungsjahr: 2012

Beschreibung

Starting out with an introduction to the fundamentals of lithium ion batteries, this book begins by describing in detail the new materials for all four major uses as cathodes, anodes, separators, and electrolytes. It then goes on to address such critical issues as self-discharge and passivation effects, highlighting lithium ion diffusion and its profound effect on a battery's power density, life cycle and safety issues. The monograph concludes with a detailed chapter on lithium ion battery use in hybrid electric vehicles. Invaluable reading for materials scientists, electrochemists, physicists, and those working in the automobile and electrotechnical industries, as well as those working in computer hardware and the semiconductor industry.

Leseprobe

Contents

Preface

List of Contributors

1 General Concepts

1.1 Brief Outline of Batteries

1.2 Early Development of Lithium-Ion Batteries

1.3 Toward a Realistic Goal

References

2 Lithium Insertion Materials Having Spinel-Framework Structure for Advanced Batteries

2.1 Introduction

2.2 Structural Description of Spinel

2.3 Derivatives of Spinel-Framework Structure

2.4 Electrochemistry of Lithium Insertion Materials Having Spinel-Framework Structure

2.5 An Application of Lithium Insertion Materials Having Spinel-Framework Structure to 12 V “Lead-Free” Accumulators

2.6 Concluding Remarks

References

3 Overlithiated Li1+x (Niz Co1−2z Mnz)1−x O2 as Positive Electrode Materials for Lithium-Ion Batteries

3.1 Introduction

3.2 Co-Free Li1+x (Ni1/2 Mn1/2)1−x O2

3.3 Li1+x (Ni1/3 Co1/3 Mn1/3)1−x O2

3.4 Other Li1+x (Niz Co1−2z Mnz)1−x O2 Materials

3.5 Conclusion

References

4 Iron-Based Rare-Metal-Free Cathodes

4.1 Introduction

4.2 2D Layered Rocksalt-Type Oxide Cathode

4.3 3D NASICON-Type Sulfate Cathode

4.4 3D Olivine-Type Phosphate Cathode

4.5 3D Calcite-Type Borate Cathode

4.6 3D Perovskite-Type Fluoride Cathode

4.7 Summary

References

5 Thermodynamics of Electrode Materials for Lithium-Ion Batteries

5.1 Introduction

5.2 Experimental

5.3 Results

5.4 Conclusion

References

6 Raman Investigation of Cathode Materials for Lithium Batteries

6.1 Introduction

6.2 Raman Microspectrometry: Principle and Instrumentation

6.3 Transition Metal-Oxide-Based Compounds

6.4 Phospho-Olivine LiMPO4 Compounds

6.5 General Conclusion

References

7 Development of Lithium-Ion Batteries: From the Viewpoint of Importance of the Electrolytes

7.1 Introduction

7.2 General Design to Find Additives for Improving the Performance of LIB

7.3 A Series of Developing Processes to Find Novel Additives

7.4 Cathodic and the Other Additives for LIBs

7.5 Conditioning

References

8 Inorganic Additives and Electrode Interface

8.1 Introduction

8.2 Transition Metal Ions and Cathode Dissolution

8.3 How to Suppress the Mn(II) Degradation

8.4 Alkali Metal Ions

8.5 Alkali Salt Coating

8.6 Summary

References

9 Characterization of Solid Polymer Electrolytes and Fabrication of all Solid-State Lithium Polymer Secondary Batteries

9.1 Molecular Design and Characterization of Polymer Electrolytes with Li Salts

9.2 Fabrication of All-Solid-State Lithium Polymer Battery

References

10 Thin-Film Metal-Oxide Electrodes for Lithium Microbatteries

10.1 Introduction

10.2 Lithium Cobalt Oxide Thin Films

10.3 LiNiO2 and Its Derivatives Compounds LiNi1−x MO2

10.4 LiMn2 O4 Films

10.5 V2 O5 Thin Films

10.6 MoO3 Thin Films

10.7 General Conclusions

References

11 Research and Development Work on Advanced Lithium-Ion Batteries for High-Performance Environmental Vehicles

11.1 Introduction

11.2 Energy Needed to Power an EV

11.3 Quest for a High-Power Characteristic in Lithium-Ion Batteries

11.4 Cell Thermal Behavior and Cell System Stability

Further Reading

Index

The Editor

Dr. Kazunori OzawaEnax, Inc.President & CEO2-11-19 Otowa, Bunkyo-kuTokyo 112-0013Japan

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ISBN: 978-3-527-31983-1

Preface

Lithium ion battery has become the basis of the huge market for cellular phones and lap top computers, and these mobile communication market continues to grow at a rapid rate, supported by the demand all over the world. Even so, intensive efforts are still under way to further improve the technology. The main target of the effort is not only the automobile industry by achieving higher energy and higher power, but also the energy storage market supplementing environmentally friendly power source such as solar energy and wind turbine.

Though the lithium ion technology is so wide this book can include only a few topics, I believe the readers can find an indicator to do the research.

Chapter one covers the basic concepts of electrochemical devices and lithium ion battery.

From Chapter two to Chapter four cathode materials are described, and Chapter two especially proposes new application such as an accumulator.

The basic thoughts of the materials are mentioned in Chapter five and Chapter six. These two Chapters are so new, then they may give a big impact to the readers.

Chapter seven and Chapter eight focus on the solid electrolyte interface, so called SEI which is important to develop high performance lithium ion batteries.

Solid state batteries are discussed in Chapter nine and Chapter ten. These batteries may show the big business chance in the future.

Las but not least, Chapter eleven explain advanced lithium ion batteries for high performance environmental vehicles.

The substantial contribution of each of the authors to this book is gratefully acknowledged, as well as their cooperation in preparing their manuscripts in the style and format selected. I also wish to express my appreciation to the companies, associations who supported the contributing authors and willingly provided their technical information and data permitted its use in this book.

Kazunori Ozawa

January, 2009

List of Contributors

Kingo Ariyoshi

Osaka City University (OCU)

Graduate School of Engineering

Department of Applied Chemistry

Sugimoto 3-3-138

Sumiyoshi, Osaka 558-8585

Japan

Rita Baddour-Hadjean

Institut de Chimie et des Matériaux

Paris-Est, ICMPE/GESMAT

UMR 7182 CNRS et Université Paris

XII, CNRS, 2 rue Henri Dunant

94320 Thiais

France

Nikolay Dimov

Saga University

Advanced Research Center

IM & T Inc.

1341 Yoga-machi, Saga 840-0047

Japan

Hideaki Horie

Nissan Motor Co., Ltd.

Nissan Research Center

1, Natsushima-cho, Yokosuka-shi

Kanagawa, 237-85223

Japan

Yuki Kato

University of Tokyo

Institute of Industrial Science

4-6-1 Komaba, Meguro-ku

Tokyo 153-8505

Japan

Jung-Min Kim

Iwate University

Graduate School of Engineering

Department of Frontier Materials

and Functional Engineering

4-3-5 Ueda, Morioka

Iwate 020-8551

Japan

Shinichi Komaba

Tokyo University of Science

Department of Applied Chemistry

1-3 Kagurazaka, Shinjuku

Tokyo 162-8601

Japan

Naoaki Kumagai

Iwate University

Graduate School of Engineering

Department of Frontier Materials

and Functional Engineering

4-3-5 Ueda, Morioka

Iwate 020-8551

Japan

Yoshinari Makimura

Toyota Central Research and

Development Laboratories, Inc.

Nagakute, Aichi 480-1192

Japan

Kenzo Matsuki

Yamagata University

4-3-16 Jonan, Yonezawa

Yamagata 992-8510

Japan

Hiroyoshi Nakamura

Saga University

Department of Applied Chemistry

1 Honjyo, Saga, 840-8502

Japan

Masanobu Nakayama

Nagoya Institute of Technology

Graduate School of Engineering

Department of Materials and

Science and Engineering

Gokiso-cho, Syowa-ku

Nagoya 466-8555

Japan

Tsutomu Ohzuku

Osaka City University (OCU)

Graduate School of Engineering

Department of Applied Chemistry

Sugimoto 3-3-138

Sumiyoshi, Osaka 558-8585

Japan

Shigeto Okada

Kyushu University

Institute for Materials Chemistry and

Engineering, 6-1, Kasuga Koen

Kasuga, 816-8580

Japan

Kazunori Ozawa

Enax, Inc.

8F Otowa KS Bldg.

2-11-19 Otowa

Bunkyo-ku, Tokyo 112-0013

Japan

Jean-Pierre Pereira-Ramos

Institut de Chimie et des

Matériaux Paris-Est

ICMPE/GESMAT, UMR 7182

CNRS et Université Paris XII, CNRS

2 rue Henri Dunant

94320 Thiais

France

Masataka Wakihara

Tokyo Institute of Technology

Office Wakihara:

Dear City Akasaka W-403

2-12-21 Akasaka Minato-ku

Tokyo 107-0052

Japan

Jun-ichi Yamaki

Kyushu University

Institute for Materials

Chemistry and Engineering

6-1, Kasuga Koen

Kasuga 816-8580

Japan

Rachid Yazami

California Institute of Technology

(CALTECH)

International Associated Laboratory

on Materials for Electrochemical

Energetics (LIA-ME2), MC 138-78

Pasadena, CA 91125

USA

Masaki Yoshio

Saga University

Advanced Research Center

1341 Yoga-machi, Saga, 840-0047

Japan

1

General Concepts

Kenzo Matsuki and Kazunori Ozawa

1.1 Brief Outline of Batteries

The first practical battery is the generally known Volta cell (also called the Galvanic cell). Its invention, over two centuries ago, spawned the invention of a variety of batteries based principally on the Volta cell. However, interestingly, during the last century, only three batteries, namely, the MnO2 primary battery and the secondary batteries of lead/acid or nickel have been in use. Knowing why such batteries continue to be used would give us some important pointers toward the development of new technology in this line. These old batteries are close to reaching their technical limit. Recently, however, new concepts have been used in the development of lithium-ion secondary batteries with higher ability.

A battery generally provides two functions – the ability to supply power over a duration of time and the ability to store power. These are defined by two operations, charge/discharge (progress of the reaction) and storage/stop (termination of the reaction), that is, a battery is a device that provides two functions, namely, energy storage and energy conversion (from chemical to electrical, and vice versa). As shown in Figure 1.1, the field of energy conversion is a multiphase system that is composed of positive/negative terminals and positive/negative active materials and electrolyte; the ions and electrons transfer through their interfaces. The interfaces reflect the nature of each phase. In addition, the state of these interfaces changes over time with the operation of the battery. The cell voltage is supported by an electric double layer with a remarkably high electric field between the electrodes and the electrolytic solution in which the electrode reactions take place. It should be emphasized that battery technology is essentially the same as the technology that controls these interfaces.

Fig. 1.1 Multilayer system composed of five phases and four interfaces.

1.1.1 Galvanic Cell System – Aqueous Electrolyte System

To understand the cell structure and its reaction, the well-known Daniel cell is schematically shown in Figure 1.2.

Fig. 1.2 Daniel cell.

The two half cells of Zn|Zn2+ and Cu|Cu2+ are combined and a separator is placed between them so that they are not miscible with each other. The formula that shows the principle and the structure of the Daniel cell is as follows:

where the symbols | and || show the interface of different phases and the liquid–liquid junction (separator), respectively.

The cathode (positive electrode) active material of the Daniel cell is the Cu2+ ion in the electrolyte, while the Zn anode (negative electrode) dissolves to form the Zn2+ ion. The drop in voltage of the cell occurs because of self-discharge of the active materials. Generally, a self-discharge tends to occur when the dissolved chemical species such as Cu2+ ion are used as the cathode-active material. This is one of the reasons that the Daniel cell was not used for practical purposes.

Cathodeand anode-active materials in the Leclanche cell are MnO2 (solid) and Zn metal, respectively. These electrode reactions are as follows:

When the discharge reaction takes place, the Zn anode dissolves to form a complex ion. Since MnO2 has a depolarizing ability that reduces the potential drop produced, the Leclanche type battery has been improved progressively to produce several kinds of batteries for commercial use, such as the manganese dry cell, the ZnCl2 cell, and the alkaline MnO2 cell.

In 1859, Plante invented the lead acid storage battery. This battery has been improved over the years and is now industrially mass-produced. The electrode reactions in the lead storage battery are described as follows:

During discharge, a secondary solid phase of PbSO4 is formed on both the anode and the cathode. Moreover, sulfuric acid in the aqueous solution – which is another active species – and water also participate in the charge/discharge reactions. These factors cause some polarizations that lower the cell performance.

Electrode reactions in Ni– Cd cell are as follows:

The cathode reaction involves the insertion of an H+ ion into the solid NiOOH, which is similar to the cathode reaction of MnO2 in the manganese battery, while the anode reaction is the formation of a secondary solid phase Cd(OH)2 on the Cd anode. This prevents a smooth reaction as the Cd anode is covered with Cd(OH)2.

The cathode-active material of nickel – metal hydride (Ni – MH) battery is the H species, which is adsorbed by the hydrogen-adsorbing alloy (MH) instead of the Cd anode of the Ni– Cd battery; the cell reaction is very simple because only hydrogen participates in the charge/discharge reaction. The Ni– MH battery has almost same voltage and larger electric capacity when compared with that of the Ni– Cd battery; moreover, it is free from environmental contamination. Therefore, the industrial production of Ni – MH battery has increased rapidly in recent years.

1.1.2 Lithium-Cell System – Nonaqueous Electrolyte System

To realize a battery with high potential of 3 V, batteries using lithium metal as the anode-active material and a powerful oxidizing agent as the cathode-active material were considered to be ideal. One such promising cathode-active material was MnO2 ; the development of lithium battery using this commenced in 1962. Fortunately, at that time, substantial amount of basic and application data with MnO2 was available. About 10 years later, an Li– MnO2 battery with a lithium metal anode was made available by SANYO Inc.; this became the first representative primary lithium battery.

Since then, considerable research and development has taken place in the design and manufacture of rechargeable lithium batteries. Many cathode-active materials such as TiSe, NbSe, MoS2, and MnO2 were studied. For example, rechargeable batteries based on a lithium metal anode and a molybdenum sulfide cathode (Li insertion electrode) were developed by MOLI Energy, Inc. in 1985. This battery system was abandoned owing to safety problems. Lithium batteries based on Li metal anodes and commonly used electrolyte systems revealed the thermal runaway of these systems, which can lead to their explosion; this was almost inevitable in abuse cases such as short circuit, overheating, and overcharging. Although the highest energy density available for Li batteries is achieved by a battery system that can use Li metal anode, a solution to safety issues needs to be found.

Active materials with good reversibility for the Li intercalation/deintercalation and low charge/discharge voltage were used as anode materials instead of Li metal. A carbon material was found to meet these requirements, and a rechargeable Li battery based on a carbon anode and LiCoO2 (layered lithium cobalt oxide) cathode was developed, mass-produced, and commercialized by Sony Inc. in 1991; this lithium-ion battery was capable of high performance as well as a high voltage of 4 V. As shown schematically in Figure 1.3, lithium-ion rechargeable batteries are charged and discharged through the transport of Li+ ions between anode and cathode, with electron exchange as a result of insertion (doping) and extraction (undoping). Both anode and cathode materials are layered compounds, and, as a result, the battery reaction is very simple because only Li+ ions participate in the charge/discharge reactions.

Fig. 1.3 Schematic illustration of the reaction in a lithium-ion battery.

The features of the Li-ion batteries, compared with the other rechargeable batteries, can be summarized as follows: (i) Charge and discharge reactions transfer Li+ ions between cathode and anode with minimal side reactions; (ii) The electrolytes work only as a path for the Li+ ions; and (iii) The volume of the electrolyte between cathode and anode will not be required.

1.2 Early Development of Lithium-Ion Batteries

The UK Atomic Energy Authority showed in their patent [1] that the intercalation and deintercalation of Ax-ion of the compound AxMyO2 reversibly occurs, where Ax is an alkaline metal and My is a transition metal. In 1990, Sony used this patent to first produce Li-ion batteries for a cellular phone HP-211. The cell sizes were 14500 and 20500, where 20 refers to the diameter and 50 the length in mm. The chemistry was LiCoO2/soft carbon system, and the capacities of the 14500 and 20500 models were only 350 and 900 mAh, respectively. The production was on a pilot scale. However, the naming of the lithium-ion rechargeable battery [2] was a marketing success. It was a controversial issue whether Li existed as ion or metal in the carbon anode. By the measurement using NMR, it was revealed that some part of the Li could exist as ion [3].

The actual mass production of the lithium-ion cell was carried out for a camcorder TR-1 in 1991. The cell size was 18650, which has the same volume as the 20500 cell. The chemistry was LiCoO2/hard-carbon system [4]. Figure 1.4 displays the inside structure of a 18650 cell.

Fig. 1.4 The inside structure of a 18650 lithium-ion cell.

The reasons for Sony’s success as the first producer of lithium-ion batteries is explained in the following section.

1.2.1 Ceramics Production Capability

Sony were already one of the biggest Mn – Zn ferrites producers in Japan. They also had considerable experience in the production of LiCoO2.

1.2.2 Coating Technology

Sony had been producing magnetic tapes for audioand videotape recorders. The coating technology for magnetic tapes was very useful and very important in making cathode and anode electrodes, especially in making good slurry and performing intermittent coating.

1.2.3 LiPF6 as a Salt for Electrolytes

LiPF6 is unstable and easily decomposes with heat and moisture. Since the acid HF is produced in the presence of water, numerous arguments opposing the use of LiPF6 were put forth in conferences and seminars. However, it was revealed that a small amount of HF increased the life cycle, because of the formation of a very strong passive layer such as AlF3 on the surface of an aluminum cathode collector [5]. LiPF6 is also easily soluble in the solvent, making it a good solid electrolyte interface (SEI) on the surface of anode materials.

1.2.4 Graphite Conductor in the Cathode

Synthesized graphite KS-15 was added as a conductor in the cathode. Since the cathode material is an oxide, which is nonconductive, a conductor has to be added. Metallic materials were also considered as conductors, but only carbon was effective for cycle performance because it acts as a reduction material giving a conductive path on the surface of the material.

1.2.5 Using Hard Carbon for the Anode

It is possible to use hard carbon and soft carbon in the form of propylene carbonate (PC) as solvent for the electrolyte. At first, soft carbon was used for the 14500 and 20500 cells, but it was changed to hard carbon in the 18650 cell after considering the float-charge stability – soft carbon is graphitizable carbon, whereas hard carbon is nongraphitizable carbon when it is heated to high temperatures of 2800– 3000°C.

1.2.6 Nonwoven Shut-down Separator

Nonwoven polyethylene (PE) separators made by Tonen could be used for the 18650 cell. This separator melted at ∼140°C and gave good safety results by shutting down the rush current in the case of abuse.

1.2.7 Ni-Plated Fe Can

Since the acid HF is produced inside the cell, a can should be made with stainless steel. However, the conductivity of stainless steel is so low that it is not suitable for the can, which requests low electroresistance. Ni-plated Fe can was then used for producing cylindrical cells.

After Sony’s commercialization, various modifications have been made to develop advanced Li+ ion batteries with higher energy density, retaining their good safety characteristics. These efforts achieved energy density of 200 W h kg−1 and 500 W h l−1, values of which would be close to those postulated earlier.

The shapes of cells have been widely expanded from cylindrical to prismatic and laminated. The applications of cells have also widely expanded from cellular phones and camcorders to laptop computers, power tools, and light electric vehicles.

Not only LiCoO2 but also LiMn2O4, LiNi1/3 Co1/3 Mn1/3O2, LiNiAlO2, etc. have been developed as cathode materials.

It has become possible to use graphite for the anode by controlling the SEI layer. However, LiPF6 is interestingly still preferred as a salt in the electrolyte, and components of the solvent are usually still cyclic carbonates such as PC, ethylene carbonate (EC), and linear carbonates such as dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl– methyl carbonates (EMC), and/or their combinations. Lithium-ion batteries are considered to be good in electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid vehicles. In tune with the increased and diverse applications, a strong demand for higher power density (kilowatts per kilograms) and higher energy density (kilowatt hours per kilogram) will become the target of the further research and development activities.

1.3 Toward a Realistic Goal

One of our final goals is a high-energy and high-power battery that can replace the lead/acid battery of automobiles satisfying EU RoHS (EU Directive: Restrictions on Hazardous Substances) instructions. To realize lead-free accumulators (engine starters), it is important to study the materials from their basic properties. Lithium insertion materials without the destruction core structures, called topotactic reactions, are classified into three categories:

1. Layer structure: LiCoO2, LiNiO2, LiNi1/2 Mn1/2O2, LiCo1/3 Ni1/3 Mn1/3O2, LiAl0.05 Co0.15 Ni0.8O2, etc. [6];

2. Spinel-frame work structure: LiMn2O4, Li[Ni1/2 Mn3/2 ]O4, LiV2O4, Li[Li1/3 Ti5/3 ]O4, etc. [7, 8];

3. Olivine structure: LiFePO4, LiMnPO4, LiCoPO4, etc. [9].

LiMn2O4 is a very attractive material as a cathode, but is reported to have a poor cycle performance. Measurement of the entropy of lithiation may indicate a solution [10], which is described in Chapter 5. Olivine structure, also called chrysoberyl structure, has a space group system of Pnma and shows excellent stability, but very low electric conductivity.

As for an accumulator of a consumer car, the battery has to have very high energy that resists overdischarging during parking. For the higher energy density, the species that have the biggest redox potential should be considered. The term redox is obtained from a contraction of the words reduction and oxidation. Table 1.1 shows the standard potentials of electrode reaction at room temperature. Lithium has the maximum potential on the negative side, and fluorine has the maximum on the positive side. These suggest our future target.

Table 1.1 Redox Potential.

It is also necessary to consider the fact that the key elements of lithium-ion batteries are facing the crisis of exhaustion. Co metal used for the cathode has been in great shortage for quite some time. Element resources in the earth were estimated as the Clarke number, which was presented about 80 years ago. These values are not fully accepted, but they suggest our standpoint.

Focusing on the transition metals, they are ranked as follows in weight:

Lithium-ion batteries are still one of the most promising storage devices. To realize the ideal battery, further development efforts are continuing all over the world.

References

1 Goodenough, J.B. and Mizushima, K. (1979) c/o United Kingdom Atomic Energy Authority, United Kingdom Patent GB 11953/79, April 1979.

2 Nagaura, T. and Tozawa, K. (1990)Prog. Batteries Sol. Cells, 9, 209.

3 Tanaka, K., Itabashi, M., Aoki, M., Hiraka, S., Kataoka, M.,Sataori, K., Fujita, S., Sekai, K. and Ozawa, K. (1993) 184th ECS Fall Meeting, New Orleans, Louisiana.

4 Ozawa, K. (1994) Solid State Ionics,69, 212.

5 Tachibana, K., Nishina, T., Endo, T., and Matsuki, K. (1999) The 1999 Joint International meeting, 196th Meeting of the Electrochemical Society, 1999 Fall Meeting of The Electrochemical Society of Japan with Technical cosponsorship of the Japan Society of Applied Physics, Honolulu, Abstract No. 381 (1999).

6 Mizushima, K., Jopnes, P.C., Wiseman, P.J., and Goodenough, J.B. (1984) Mater. Res. Bull., 19, 170.

7 Hunter, J.C. (1981) J. Solid StateChem., 39, 142.

8 Thackeray, M.M., Johnson, P.J., de Piciotto, L.A., Bruce, P.G., and Goodenough, J.B. (1984) Mater. Res. Bull., 19, 179.

9 Phadhi, A.K., Nanjundaswang, K.S., and Goodenough, J.B. (1997) J. Electrochem. Soc., 144, 1188.

10 Yazami, R., Reynier, Y., and Fultz, B. IMLB 2006, Biarritz, France.

2

Lithium Insertion Materials Having Spinel-Framework Structure for Advanced Batteries

Kingo Ariyoshi, Yoshinari Makimura, and Tsutomu Ohzuku

2.1 Introduction

Lithium-ion batteries are popular worldwide as power sources for wireless telephones, laptop computers, and other electronic devices. Current lithium-ion batteries mostly consist of LiCoO2 and graphite, which are the layered structures. Possible alternatives to LiCoO2 and graphite have been intensively investigated by many research groups over the past 15 years, and many lithium insertion materials have been reported [1 – 4]. However, LiCoO2 and graphite continue to be used in lithium-ion batteries because of their high-energy density. Current lithium-ion batteries have about 550 Wh dm−3 of volumetric energy density. Because graphite shows the lowest operating voltage against lithium with the high rechargeable capacity of more than 350 mAh g−1 and LiCoO2 shows a flat operating voltage of about 4 V versus Li with rechargeable capacity of about 140 mAh g−1, it is very difficult to replace LiCoO2 or graphite with other lithium insertion materials with respect to energy density. Recently, possible applications of batteries have diversified from high energy density to high power density and long life owing to environmental issues. This new direction gives us a chance to promote research on brand-new batteries and materials. Lithium insertion materials having spinel-framework structure described in this chapter fit applications that require high power and long life.

We review the crystal structure of spinel in Section 2.2, in which the structural feature of spinel in relation to a lithium insertion scheme is described. Derivatives of spinel-framework structure are explained by lowering the crystal symmetry of cubic spinel and a series of crystal structures in terms of superstructure due to cation ordering are discussed in Section 2.3.