Molten chloride salts for next generation CSP plants: Electrolytical salt purification for reducing corrosive impurity level

Potential scalability of a cost-effective purification method for MgCl2-Containing salts for next-generation concentrating solar power technologies

Thermal batteries with molten salt electrolytes are used for many military applications, primarily as power sources for guided missiles The Li–B/CoS2 couple is designed for high-power, high-voltage thermal batteries However, their capacity and safe properties are influenced by acute self-discharge that results from the dissolved lithium anode in molten salt electrolytes To solve those problems, in this paper, carbon coated CoS2 was prepared by pyrolysis reaction of sucrose at 400 °C The carbon coating as a physical barrier can protect CoS2 particles from damage by dissolved lithium and reduce the self-discharge reaction Therefore, both the discharge efficiency and safety of Li–B/CoS2 thermal batteries are increased remarkably Discharge results show that the specific capacity of the first discharge plateau of carbon-coated CoS2 is 243 mA h g−1 which is 50 mA h g−1 higher than that of pristine CoS2 at a current density of 100 mA cm−2 The specific capacity of the first discharge plateau at 500 mA cm−2 for carbon-coated CoS2 and pristine CoS2 are 283 mA h g−1 and 258 mA h g−1 respectively The characterizations by XRD and DSC indicate that the carbonization process has no noticeable influence on the intrinsic crystal structure and thermal stability of pristine CoS2

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Suppressing self-discharge of Li─B/CoS2 thermal batteries by using a carbon-coated CoS2 cathode

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Molten Chloride Thermophysical Properties, Chemical Optimization, and Purification

This chapter is concerned with electroanalytical chemistry in molten salts. Electroanalysis has been applied extensively for in situ determination and characterization of solutes in molten salt solvents. This field has been reviewed previously(1–6)† either alone or in conjunction with other topics. In this review we shall stress more recent developments (1965–1971) in several important solvent systems. We shall exclude the discussion of transport properties and related topics, the electrical double layer, and the rates of charge-transfer processes, since the reviews of these topics(6–8) are quite up to date.

Electroanalytical Chemistry in Molten Salts—A Review of Recent Developments

溶融塩化リチウム- 塩化カリウム混合塩に対する金属リチウムの溶解度を測定し, 酸素, 窒素が溶解度に及ぼす影響を調べた。450℃で共融塩に対する溶解度はきわめて小さく約0.1mol%であった。従来, 金属の電解製造における電流効率低下の主要な原因は金属の浴中への溶解に起因するものと考えられていたが,この結果によると,電析したリチウムが空気中の水分,酸素,窒素と反応して生成したリチウム化合物が浴中へ溶解することが主要な原因の一つであることが明らかとなった。

Solubility of Lithium in Molten Lithium Chloride-Potassium Chloride System

溶融MgCl2 系に対する金属Mgの溶解度とMg濃淡電池の起電力が750℃で測定された。Mg濃淡電池の起電力はMgの濃度の対数に直線的に依存することがわかった。この依存性の勾配からMgの溶解生成物はMgoまたはMg22+であることが推定された。溶融MgCl2に対するMgの溶解度はアルカリ塩化物の添加によって減少し, その減少割合はアルカリ金属の原子番号の増加とともに増大することが認められた。アルカリ塩化物系ではその原子番号の増加とともにMgCl2との錯形成能が増大するので, Mgの溶解度は溶解塩中のMg2+ 活量に比例すると考えられる。したがって, 溶融塩中におけるMgの溶解種はMgoよりもむしろMg22+イオンであると結論されるであろう。

Koichiro Nakanishi

Papers

Solubility of Lithium in Molten Lithium Chloride-Potassium Chloride System

Solubility of Magnesium in Molten Magnesium Chloride