In the previous paper Ralph Brodd and Martin Winter described the different kinds of batteries and fuel cells. In this paper I will describe lithium batteries in more detail, building an overall foundation for the papers that follow which describe specific components in some depth and usually with an emphasis on the materials behavior. The lithium battery industry is undergoing rapid expansion, now representing the largest segment of the portable battery industry and dominating the computer, cell phone, and camera power source industry. However, the present secondary batteries use expensive components, which are not in sufficient supply to allow the industry to grow at the same rate in the next decade. Moreover, the safety of the system is questionable for the large-scale batteries needed for hybrid electric vehicles (HEV). Another battery need is for a high-power system that can be used for power tools, where only the environmentally hazardous Ni/ Cd battery presently meets the requirements. A battery is a transducer that converts chemical energy into electrical energy and vice versa. It contains an anode, a cathode, and an electrolyte. The anode, in the case of a lithium battery, is the source of lithium ions. The cathode is the sink for the lithium ions and is chosen to optimize a number of parameters, discussed below. The electrolyte provides for the separation of ionic transport and electronic transport, and in a perfect battery the lithium ion transport number will be unity in the electrolyte. The cell potential is determined by the difference between the chemical potential of the lithium in the anode and cathode, ∆G ) -EF. As noted above, the lithium ions flow through the electrolyte whereas the electrons generated from the reaction, Li ) Li+ + e-, go through the external circuit to do work. Thus, the electrode system must allow for the flow of both lithium ions and electrons. That is, it must be both a good ionic conductor and an electronic conductor. As discussed below, many electrochemically active materials are not good electronic conductors, so it is necessary to add an electronically conductive material such as carbon * To whom correspondence should be addressed. Phone and fax: (607) 777-4623. E-mail: stanwhit@binghamton.edu. 4271 Chem. Rev. 2004, 104, 4271−4301

http://www.chemie.uni-regensburg.de/Anorganische_Chemie/Vortrag/StudentenWS06-07/Vortrag_Amereller.pdf

Lithium Batteries and Cathode Materials

Positive electrodes for Li-ion and lithium batteries (also termed “cathodes”) have been under intense scrutiny since the advent of the Li-ion cell in 1991. This is especially true in the past decade. Early on, carbonaceous materials dominated the negative electrode and hence most of the possible improvements in the cell were anticipated at the positive terminal; on the other hand, major developments in negative electrode materials made in the last portion of the decade with the introduction of nanocomposite Sn/C/Co alloys and Si−C composites have demanded higher capacity positive electrodes to match. Much of this was driven by the consumer market for small portable electronic devices. More recently, there has been a growing interest in developing Li−sulfur and Li−air batteries that have the potential for vastly increased capacity and energy density, which is needed to power large-scale systems. These require even more complex assemblies at the positive electrode in order to achieve good properties. This r...

Positive Electrode Materials for Li-Ion and Li-Batteries†

Nanostructured materials lie at the heart of fundamental advances in efficient energy storage and/or conversion, in which surface processes and transport kinetics play determining roles. This Review describes some recent developments in the synthesis and characterization of nanostructured cathode materials, including lithium transition metal oxides, vanadium oxides, manganese oxides, lithium phosphates, and various nanostructured composites. The major goal of this Review is to highlight some new progress in using these nanostructured materials as cathodes to develop lithium batteries with high energy density, high rate capability, and excellent cycling stability resulting from their huge surface area, short distance for mass and charge transport, and freedom for volume change in nanostructured materials.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/adma.200702242

Developments in Nanostructured Cathode Materials for High‐Performance Lithium‐Ion Batteries

The olivine LiFePO4 now stands as a competitive candidate of cathode material for the next generation of a green and sustainable lithium-ion battery system due to its long life span, abundant resources, low toxicity, and high thermal stability. In this review, we focus on LiFePO4 and discuss its structure, synthesis, electrochemical behavior, mechanism, and the problems encountered in its application. The major goal is to highlight some recent development of LiFePO4 with high rate capability, high energy density, and excellent cyclability resulting from conductive coating, nanocrystallization, or preparation.

Development and challenges of LiFePO4 cathode material for lithium-ion batteries

For more than 20 years, most of the technological achievements for the realization of positive electrodes for practical rechargeable Li battery systems have been devoted to transition metal oxides such as LixMO2 (M = Co, Ni, Mn), LixMn2O4, LixV2O5, or LixV3O8. The first two classes of materials built on close-packed oxygen stacking adopt bidimensional and tridimensional crystal structures, respectively (Figure 1), from which lithium ions may be easily intercalated or extracted in a reversible manner. These oxides are reasonably good ionic and electronic conductors, and lithium insertion/extraction proceeds while operating on the M4+/M3+ redox couple, located between 4 and 5 V versus Li+/Li...

Polyanionic (phosphates, silicates, sulfates) frameworks as electrode materials for rechargeable Li (or Na) batteries.

LiFePO4 powders were synthesized under two different conditions ~hydrothermal or mechanochemical activation! using iron~II! phosphate and lithium phosphate as starting materials. The samples were characterized by X-ray diffraction, chemical titration, and their electrochemical performance was investigated in terms of cycling behavior and impedance response. We also report the benefit of introducing an electronic conductor precursor ~typically a sucrose! during or after the synthesis to overcome the poor charge transfer associated to the lithium iron phosphate.

https://iopscience.iop.org/article/10.1149/1.1506962/pdf

LiFePO4 Synthesis Routes for Enhanced Electrochemical Performance

Structural and electrochemical properties of a new highly rechargeable lithium iron phosphate are described here, Its behavior as cathodic material was also tested in a complete power system based on a nanocrystalline Li 4 Ti 5 O 12 anode and a nonaqueous liquid electrolyte (1 mol L -1 LiPF 6 in ethylene carbonate/dimethyl carbonate). This cell operates with a very flat voltage profile at around 2 V, with very little capacity fading upon cycling, even at a very high rate (4C or 8C). These features, combined with the low cost and the lack of toxicity of the components, make this system an attractive and inexpensive power source for the low voltage electronic market.

C. Bourbon

Papers

LiFePO4 Synthesis Routes for Enhanced Electrochemical Performance

Optimized Lithium Iron Phosphate for High-Rate Electrochemical Applications

Chemistry and electrochemistry of composite LiFePO4 materials for secondary lithium batteries

Raman study of the spinel-to-layered phase transformation in sol–gel LiCoO2 cathode powders as a function of the post-annealing temperature

Chemistry and electrochemistry of nanostructured iron oxyhydroxides as lithium intercalation compounds for energy storage