チオビスリチウム

化学的特性Lithium sulfide is the inorganic compound with the formula Li2S. It crystallizes in the antifluorite motif, described as the salt (Li+)2S2−. It forms a solid yellow-white deliquescent powder. In air, it easily hydrolyses to release hydrogen sulfide (rotten egg odor) Lithium sulfide is prepared by treating lithium with sulfur. This reaction is conveniently conducted in anhydrous ammonia. The THF-soluble triethylborane adduct of lithium sulfide can be generated using superhydride. Lithium sulfide (Li2S) is considered the promising cathode material for its high theoretical capacity, high melting point, affordable volume expansion, and lithium composition.

解説硫化リチウムとは、化学式はLi2Sで表わされるの硫化物です。 別称としては、硫化二リチウム、チオビスリチウム、ジリチオスルフィドがあります。通常無色～白色の粉末状であり、卵の腐ったような独特の臭気 (腐卵臭) があることが特徴です。不燃性ですが、加熱や酸類との接触によりやが発生します。 また、水に溶けやすいが加水分解しやすく、潮解性があります。水との接触時には発熱を伴い、水溶液はアルカリ性です。水溶液は硫黄を溶解し、Li2S2、Li2S4といったポリ硫化物を生じます。

使用Lithium sulfide (Li2S) is a product specially designed for the use in high performance batteries which can be either applied as electrode material or as precursor for solid electrolytes. It as an electrode material not only has high capacity but also overcomes many problems caused by pure sulfur electrodes. Lithium sulfide is an anti fluorite semiconductor (bandgap 3.865eV). It exists in orthorhombic and cubic structures. The densities of the orthorhombic and cubic structures are 1.75g/cm3 and 1.63g/cm3 respectively. Lithium sulfide has been studied as a MgB2- like superconductor. It is also used as a cathode material in rechargeable lithium-sulfur batteries.

一般的な説明Lithium sulfide is an anti fluorite semiconductor (bandgap 3.865eV). It exists in orthorhombic and cubic structures. The densities of the orthorhombic and cubic structures are 1.75g/cm3 and 1.63g/cm3 respectively.

使用用途硫化リチウムは、全固体電池における正極活物質および固体電解質として有望視されています。近年、電子機器の発達に伴い、二次電池の高密度化、安全性向上が求められており、現行の (LiB) を代替する次世代二次電池の研究開発が進められています。 そこで、注目されているのが全固体電池であり、なかでも特に期待を集めているのが全固体リチウム-硫黄電池 (LiSB) です。全固体リチウム硫黄電池が実用化されると、ポータブル電子機器だけでなく電気自動車や航空機といった用途拡大が期待されます。

製造方法Lithium sulfide, Li2S, is formed in the reaction of lithium with sulfur in liquid ammonia, by the decomposition of the ethanol adduct of lithium hydrogen sulfide with lithium ethanolate, and, more recently, by the reaction of hydrogen sulfide with lithium amylate to yield lithium hydrogen sulfide, LiSH, which is thermally decomposed in a vacuum to yield the sulfide. A very high quality anhydrous lithium sulfide may be prepared by the reaction of lithium metal and hydrogen sulfide in tetrahydrofuran if care is taken to exclude water. The reaction product is filtered from the reaction medium, and it is vacuum dried to remove tetrahydrofuran and to decompose the small amount of lithium hydrogen sulfide which forms. Lithium sulfide is reported to have an antifluorite structure. Lithium sulfide is readily hydrolyzed, even by water in the air, yielding hydrogen sulfide. The sulfide also reacts with sulfur to form a variety of polysulfides.