在這項研究中，我們研究了各種鋰鹽的氨化電萃溶液的電化學性質，以試圖將氨化電萃溶液用作Li-S電池中的液體電解質。鋰鹽包括LiBH4，LiClO4，LiNO3，LiTFSI，LiFSI，LiTriflate。氨化電萃溶液通常在放置於不銹鋼反應器中，在0.56 atm的氨氣分壓下形成。也可以將所述電萃溶液摻入Li-PAA樹脂中，並與20、30、40重量％的鋰鹽一起當作凝膠型電解質。
氨化的電子溶液的離子電導率很高，在室溫下通常約為10-3 S cm-1。LiClO4（或LiClO4 + LiNO3）的透明電萃溶液的離子電導率達到6x10-3 S cm-1。用循環伏安法測量電萃溶液的穩定性，發現電位窗口幾乎相同，為3.8 V。潛在的窗口大小主要取決於鋰鹽的氨化帶來的自由能下降。電位窗口大小對於Li-S電池已經足夠，其鋰離子電池的電位上限低於3.0 V.
氨化的電萃溶液不溶於多硫化物作為電解質。電萃溶液具有不溶多硫化物的巨大優勢，因為溶解的多硫化物會引起多硫化物的穿梭問題以及Li-S電池不可逆的電容量衰減。不幸的是，氨化的電萃溶液在直接接觸時也會與鋰金屬電極反應。我們嘗試了許多方法來保護氨化的電萃溶液免於與鋰金屬反應，但是失敗了。在鋰陽極上形成的類SEI無法提供足夠的氨防護。因此，我們組裝的Li-S電池是容量~1086 mA h g-1的一次電池。

In this study, we studied the electrochemical properties of ammoniated electride solutions of various lithium salts solvated by ammonia in an attempt to apply the ammoniated electride solution as the liquid electrolyte in the Li-S battery. The lithium salts include LiBH4, LiClO4, LiNO3, LiTFSI, LiFSI, LiTriflate. The ammoniated electride solution is generally formed in a stainless steel chamber under 0.56 atm ammonia in an argon atmosphere of 5.0 atm. The electride solution can also be incorporated in Li-PAA resin and utilized as a gel-type electrolyte with lithium salt 20, 30, 40 wt%.
The ion conductivity of the ammoniated electride solution is high, generally in the order of magnitude 10-3 S cm-1 at room temperature. The conductivity of the transparent electride solution of LiClO4 (or LiClO4+LiNO3) reaches 6x10-3 S cm-1. The stability of electride solutions is measured with cyclic voltammetry and found to be more and less the same, 3.8 V. The potential window size is mainly determined by the free energy benefits brought by ammonia solvation of lithium salts. The potential window size is sufficient for the Li-S battery, of which the upper potential limit is less than 3.0 V.
As an electrolyte, the ammoniated electride solution does not dissolve the polysulfides. The insoluble polysulfides in ammoniated electride solution offer a huge advantage over other electrolytes, since dissolved polysulfides cause the polysulfide shuttle problem and irreversible capacity decay of the Li-S battery. Unfortunately, the ammoniated electride solution also reacts with the lithium metal electrode upon direct contact. We have tried many approaches to protect the ammoniated electride solution from reaction with lithium metal, but failed. Common SEIs formed on the lithium anode cannot provide sufficient protection from ammonia. Consequently, the Li-S battery that we assembled is a primary battery with a capacity ~1086 mAh g-1.

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