Lithium batteries using nonaqueous electrolyte

All lithium based batteries use nonaqueous electrolytes because of the reactivity of lithium in aqueous solution and because of the electrolyte s stability at high voltage. The majority of these cells use microporous membranes made of polyolefins. In some cases, nonwovens made of polyolefins are either used alone or with microporous separators. This section will mainly focus on separators used in secondary lithium batteries followed by a brief summary of separators used in lithium primary batteries. 

Defined narrowly, the lithium-ion battery (LIB) is a secondary battery using nonaqueous electrolyte with carbonaceous material as a negative electrode and a metal oxide compound containing hthium (usually LiCo02) as a positive electrode [1]. The LlB s electrochemical system is shown in Fig. 1. 

Lithium batteries use nonaqueous solvents for the electrolyte because of the reactivity of lithium in aqueous solutions. Organic solvents such as acetonitrile, propylene carbonate, and dimethoxyethane and inorganic solvents such as thionyl chloride are typically employed. A compatible solute is added to provide the necessary electrolyte conductivity. (Solid-state and molten-salt electrolytes are also used in some other primary and reserve lithium cells see Chaps. 15, 20, and 21.) Many different materials were considered for the active cathode material sulfur dioxide, manganese dioxide, iron disulfide, and carbon monofluoride are now in common use. The term lithium battery, therefore, applies to many different types of chemistries, each using lithium as the anode but differing in cathode material, electrolyte, and chemistry as well as in design and other physical and mechanical features. 

Jones, G. Dole, M. (1929). The transference number of barium chloride as a function of the concentration. Journal of the American Chemical Society, 51, (1929), 1073-1091 Kaminsky M. (1957). The concentration and temperature dependence of the viscosity of aqueous solutions of strong electrolytes. III. KCl, K2SC>4, MgC12, BeS04, and MgS04 solutions. Zeitschrift filer Physikalische Chemie, 12, (1957), 206-231 Kaneko, S. Kono, Y. Kobayashi, H. Ishikawa, H. Utsuki, K. (2009). Nonaqueous electrolyte solution, gel electrolyte, and secondary lithium battery using the electrolyte solution and the gel electrolyte. Jpn. Kokai Tokkyo Koho (2009), ]P 2009140641 A 20090625... 

Lithium batteries must use nonaqueous electrolytes, usually combinations of solvents, for stabiUty because lithium reacts readily with water. Many of... 

Most battery systems in which lithium is applied as anode material belong to the group using nonaqueous electrolytes, but there is one system that works with water serving as solvent and reactant as well. 

Carbon-Lithium Rechargeable Batteries. The carbon-lithium batteries use a lithium alloy for the negative active material, a nonaqueous organic electrolyte, such as propylene carbonate, and activated carbon for the positive electrode. The battery is built in a discharged state. The mode of operation and the reactions during charge and discharge are delineated as follows ... 

The primary and secondary batteries based on lithium use nonaqueous electrolytes because of the reactivity of Hthium with aqueous solutions. 

Primary and secondary lithium batteries using a nonaqueous electrolyte, exhibit higher energy density than aqueous electrolyte-based batteries due to the cell potential higher than 1.23 V, the thermodynamic limitation of water at 25 °C. The excellent performances of nonaqueous lithium batteries may meet the need for high power batteries in micro-devices, portable equipment, and even electrical vehicles. 

Choy SH, Noh HG, Lee HY, Sun HY, Kim HS (2005) Nonaqueous electrolyte composition for improving overcharge safety and lithium battery using the same. U.S. Patent 6,921,612. Accessed 26 July 2005... 

This section reports on the current state of knowledge on nonaqueous electrolytes for lithium batteries and lithium-ion batteries. The term electrolyte in the current text refers to an ion-conducting solution which consists of a solvent S and a salt, here generally a lithium salt. Often 1 1-salts of the LiX type are preferred for reasons given below only a few l 2-salts Li2X have attained some importance for batteries, and 1 3-salts Li3X are not in use. 

As to anodes, in most of the research work a generously dimensioned sheet of lithium metal has been used. Such an electrode is rather irreversible, but this is not noticed when a large excess of lithium is employed. Li-Al alloys and carbon materials inserting lithium cathodically during recharging can be used as anodes in nonaqueous solutions. Zinc has been used in polymer batteries with aqueous electrolyte (on the basis of polyaniline). 

In the nonaqueous organic solvent-based systems used for lithium batteries, the conductivities are of the order of 10 —10 S/cm k Compared to water, most organic solvents have a lower solvating power and a lower dielectric constant. This favors ion pair formation, even at low salt concentration. Ion pair formation lowers the conductivity as the ions are no longer free and bound to each other. Organic electrolytes show lower conductivities and much higher... 

Electrolytes are ubiquitous and indispensable in all electrochemical devices, and their basic function is independent of the much diversified chemistries and applications of these devices. In this sense, the role of electrolytes in electrolytic cells, capacitors, fuel cells, or batteries would remain the same to serve as the medium for the transfer of charges, which are in the form of ions, between a pair of electrodes. The vast majority of the electrolytes are electrolytic solution-types that consist of salts (also called electrolyte solutes ) dissolved in solvents, either water (aqueous) or organic molecules (nonaqueous), and are in a liquid state in the service-temperature range. [Although nonaqueous has been used overwhelmingly in the literature, aprotic would be a more precise term. Either anhydrous ammonia or ethanol qualifies as a nonaqueous solvent but is unstable with lithium because of the active protons. Nevertheless, this review will conform to the convention and use nonaqueous in place of aprotic .]... 

Another approach is to use a lithium/sulfur cell with nonaqueous electrolyte systems. Rechargeable lithium batteries are being developed for portable power applications such as electric vehicles, partly because of their specific energy ranges 100-150 Wh kg (and... 

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