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DOE OSTI · 2326216

Sulfide glass solid-state electrolyte separators for Li metal batteries: using an interlayer to increase rate performance and reduce stack pressure

Yersak, Thomas A.·Kang, Chansoon·Salvador, James R.·Pieczonka, Nicholas P. W.·Cai, Mei
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Abstract

We report on the solubility of (Li 2 S) 60 (SiS 2 ) x (P 2 S 5 ) 40–x , (0 ≤ x ≤ 40) sulfide glass solid-state electrolytes in the 1:1 (v/v) DME:DOL solvent mixture, a popular choice for lithium metal battery liquid electrolytes. SiS 2 -rich glasses within the compositional range of (Li 2 S) 60 (SiS 2 ) x (P 2 S 5 ) 40–x (28 ≤ x ≤ 40) were found to be functionally insoluble in DME:DOL. Hybrid symmetric test cells with a thin liquid electrolyte layer (0.6 M LiTFSI + 0.4 M LiNO 3 in 1:1 (v/v) DME:DOL) at the interface between lithium metal electrodes and an insoluble (Li 2 S) 60 (SiS 2 ) 28 (P 2 S 5 ) 12 glass wafer were tested. Hybrid test cells delivered a critical current density of 3.0 mA cm –2 at 25 °C and 0.1 MPa, which is nearly double the CCD of comparable dry symmetric test cells cycled at 10× higher stack pressure.

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Yersak, Thomas A., Kang, Chansoon, Salvador, James R., Pieczonka, Nicholas P. W., Cai, Mei. 2022-05-16. Sulfide glass solid-state electrolyte separators for Li metal batteries: using an interlayer to increase rate performance and reduce stack pressure. https://doi.org/10.1039/d1ma00926e

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