Electrochemistry lithium battery electrodes

Johnson CS et al (2008) Synthesis, characterization and electrochemistry of lithium battery electrodes xLi2Mn03 (l-x)LiMn0.333Ni0.333Co0.33302 (0 < x<0.7). Chem Mater 20 6095-6106. doi 10.1021/cm801245r... 

Apart from the work toward practical lithium batteries, two new areas of theoretical electrochemistry research were initiated in this context. The first is the mechanism of passivation of highly active metals (such as lithium) in solutions involving organic solvents and strong inorganic oxidizers (such as thionyl chloride). The creation of lithium power sources has only been possible because of the specific character of lithium passivation. The second area is the thermodynamics, mechanism, and kinetics of electrochemical incorporation (intercalation and deintercalation) of various ions into matrix structures of various solid compounds. In most lithium power sources, such processes occur at the positive electrode, but in some of them they occur at the negative electrode as well. 

A major part of the work with nonaqueous electrolyte solutions in modern electrochemistry relates to the field of batteries. Many important kinds of novel, high energy density batteries are based on highly reactive anodes, especially lithium, Li alloys, and lithiated carbons, in polar aprotic electrolyte systems. In fact, a great part of the literature related to nonaqueous electrolyte solutions which has appeared during the past two decades is connected to lithium batteries. These facts justify the dedication of a separate chapter in this book to the electrochemical behavior of active metal electrodes. 

Novak R, Joho F, Lanz M., Rykart B., Panitz J.-C., Alliata D., Kbtz R., Haas O. The complex electrochemistry of graphite electrodes in lithium-ion batteries, J. Power Sources 2001, 97-98, 39-46. 

A unique approach in nonaqueous electrochemistry which may be applicable to several fields, especially for batteries, was recently presented by Koch et al. (private communication). They showed that it is possible to use solid matrices based on lithium salts contaminated with organic solvents as electrolyte systems. These systems demonstrate several advantages over liquid systems based on the same solvents and salts as solutions. Their electrochemical windows are larger, especially in the anodic direction (oxidation reactions), and it appears that their reactivity toward active electrodes (e.g., Li, Li—C) is much lower than that of the liquid electrolyte systems. 

There is no question that the development and commercialization of lithium ion batteries in recent years is one of the most important successes of modem electrochemistry. Recent commercial systems for power sources show high energy density, improved rate capabilities and extended cycle life. The major components in most of the commercial Li-ion batteries are graphite electrodes, LiCo02 cathodes and electroljde solutions based on mixtures of alkyl carbonate solvents, and LiPFe as the salt. The electrodes for these batteries always have a composite structure that includes a metallic current collector (usually copper or aluminum foil/grid for the anode and cathode, respectively), the active mass comprises mierometric size particles and a polymeric binder. 

Koura, N. lizuka, K. Idemoto, Y, Ui, K., Li and li-Al negative electrode characteristics for the lithium secondary battery with a nonflammable SOCI2, Li added, liQ saturated AICI3-EMIC molten salt electrolyte. Electrochemistry 1999, 67, 706—712. 

Lalia, B. S. Yoshimoto, N. Egashira, M. Morita, M., Electrochemical performances of nonflammable gel electrolyte for lithium ion battery using LiFeP04 positive electrode. Electrochemistry 2010, 78, 332-335. 

Electrodes. Its chemical inertness, its wide range of usable potential (1.2 to -1.0 V vs. SCE) and the hydrodynamic and structural advantages of its open-pore foam structure make vitreous carbon foam an attractive material for electrodes for lithium-ion and other types of batteries, with many potential applications in electrochemistry.[ l[ ll ]... 

Idemoto Y, Narai H, Koura N (2002) Oxygen content and electrode characteristics of LiMni 5Nio.504 as a 5 V class cathode material for lithium secondary battery. Electrochemistry 70 587-589... 

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