Lithium electrochemical alloys

Lithium. Several processes for lithium [7439-93-2], Li, metal production have been developed. The Downs cell with LiCl—KCl electrolyte produces lithium ia much the same manner as sodium is produced. Lithium metal or lithium—aluminum alloy can be produced from a mixture of fused chloride salts (108). Granular Li metal has been produced electrochemically from lithium salts ia organic solvents (109) (see LiTHlUM AND LITHIUM compounds). 

These compounds may reduce the reactivity of lithium and make the lithium deposition morphology smoother as a result of the spontaneous electrochemical alloy formation during the charging of lithium on the anode. The lithium was plated on... 

Metal halide Eff, 10 (%) Electrochemical alloying efficiency of metals with lithium [271... 

Frazer EJ. Electrochemical formation of lithium-aluminum alloys in propylene carbonate electrolytes. J Electroanal Chem 1981 121 329-339. 

Baranski AS, Fawcett WR. The formation of lithium-aluminum alloys at an aluminum electrode in propylene carbonate. J Electrochem Soc 1982 129 901-907. 

Geronov Y, Zlatilova P, Staikov G. The secondary lithium-aluminum electrode at room temperature II. Kinetics of the electrochemical formation of the lithium-aluminum alloy. J Power Sources 1984 12 155-165. 

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. 

Nonaqueous solvents can form electrolyte solutions, using the appropriate electrolytes. The evaluation of nonaqueous solvents for electrochemical use is based on factors such as -> dielectric constant, -> dipole moment, - donor and acceptor number. Nonaqueous electrochemistry became an important subject in modern electrochemistry during the last three decades due to accelerated development in the field of Li and Li ion - batteries. Solutions based on ethers, esters, and alkyl carbonates with salts such as LiPF6, LiAsly, LiN(S02CF3)2, LiSOjCFs are apparently stable with lithium, its alloys, lithiated carbons, and lithiated transition metal oxides with red-ox activity up to 5 V (vs. Li/Li+). Thereby, they are widely used in Li and Li-ion batteries. Nonaqueous solvents (mostly ethers) are important in connection with other battery systems, such as magnesium batteries (see also -> nonaqueous electrochemistry). 

Limthongkul P, Jang Y-I, Dudney NJ, Chiang Y-M (2003) Electrochemically-driven solid-state amorphization in lithium-silicon alloys and implications for lithium storage. Acta Mater 51 1103-1113... 

I = 7/2-1—> 5/2-F). The materials that can be studied, thanks to the Mossbauer effect of the above-mentioned nuclei, are also varied. Both cathode and anode materials can be examined. Moreover, the electrochemical reactions in which they are involved may vary from intercalation to conversion and/or alloying. Table 28.1 shows some examples. Fe MS provides useful information in the study of insertion cathodes, such as olivine LiFeP04, as well as layered solids structurally related to LiCo02. Fe MS is also useful to analyze anodes consisting of binary or ternary oxides for conversion reactions, or tin intermetallics that react with lithium by alloying processes. In the latter case, a multiisotope approach can be developed, due to the Mossbauer effect of both Fe and Sn nuclei. 

Lithium can alloy or react with a large number of elements or compounds, but in different ways. The major types of reactions found in electrochemical systems are (i) formation reactions, (ii) conversion reactions and (iii) insertion reactions [5]. When considering the possible reaction of lithium with other elements, it is useful to first have a look at the corresponding phase diagrams, even though most reactions do not occur at thermodynamic equilibrium. 

Szwarc R et al (1982) Discharge characteristics of lithium-boron alloy anode in molten salt thermal cells. J Electrochem Soc 129 1168-1173... 

Sanchez P et al (1992) Preparation and characterization of lithium-boron alloys electrochemical studies as anodes in molten salt media, and comparison with pure lithium-involving systems. J Mater Science 27 240-246... 

Dey AN (1971) Electrochemical alloying of lithium in organic electrol3ftes. J Electrochem Soc 118 1547-1549... 

Hudak NS, Huber DL (2012) Size effects in the electrochemical alloying and cycling of electrodeposited aluminum with lithium. J Electrochem Soc 159 A688-A695... 

To a large extent calcium anode thermal batteries are being displaced by ones using lithium rich alloys as discussed below. Lithium types avoid unwanted side reactions which characterize the calcium types which have electrochemical elEciencies down to 20% of theoretical values. 

Eagle Richer entered into the development of the lithium-metal sulphide battery system for vehicle propulsion in 1975. The electrochemical system under study utilizes an anode of a lithium-aluminium alloy and a cathode of the metal sulphides. Iron sulphide (FeS) or iron disulphide (Fe 2) is currently most commonly utilized. Initial efforts were directed toward... 

Nano-Electrochemical Approach for Improvement of Lithium-Tin Alloy Anode... 

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