Standalone sulfide based lithium ion-conducting glass solid electrolyte and associated structures, cells and methods
A standalone lithium ion-conductive solid electrolyte including a freestanding inorganic vitreous sheet of sulfide-based lithium ion conducting glass is capable of high performance in a lithium metal battery by providing a high degree of lithium ion conductivity while being highly resistant to the initiation and/or propagation of lithium dendrites. Such an electrolyte is also itself manufacturable, and readily adaptable for battery cell and cell component manufacture, in a cost-effective, scalable manner.
1. A standalone lithium ion-conductive solid electrolyte, comprising:
a freestanding inorganic vitreous sheet of sulfide-based lithium ion conducting glass having,
a liquid-like surface;
an area of at least 10 cm 2 ;
a thickness of no more than 100 μm; and
a room temperature intrinsic lithium ion conductivity of at least 10 −5 S/cm.
2. The electrolyte of claim 1 , wherein the glass sheet has a substantially uniform thickness of no more than 100 μm.
3. The electrolyte of claim 1 , wherein the glass sheet further comprises substantially parallel lengthwise edges.
4. The electrolyte of claim 1 , wherein the glass sheet is a continuous web at least 100 cm in length.
5. The electrolyte of claim 1 , wherein the glass sheet is a continuous web at least 1000 cm in length.
6. The electrolyte of claim 1 , wherein the vitreous sulfide-based glass sheet is characterized as having a threshold current for Li dendrite initiation that is greater than 1 mA/cm 2 .
7. The electrolyte of claim 1 , wherein the liquid-like surface lacks surface flaws having a depth dimension greater than 1% of the sheet thickness.
8. The electrolyte of claim 1 , wherein the sheet lacks of powder particles, inter-particle boundaries, or contiguous voids extending between first and second principal surfaces that are sufficient to propagate a Li dendrite, and the liquid-like surface lacks flaw manifestations of a pressed powder compact that are sufficient to initiate Li dendrite penetration.
9. The electrolyte of claim 1 , wherein the sulfide glass has a glass stability factor {Tx−Tg}<100° C.
10. The electrolyte of claim 1 , wherein the sulfide glass has a glass stability factor {Tx−Tg}<50° C.
11. The electrolyte of claim 1 , wherein the sulfide glass has a glass stability factor {Tx−Tg}<30° C.
12. The electrolyte of claim 1 , wherein the sulfide-based glass is of a type Li2S—YSn; Li2S—YSn—YOn and combinations thereof, wherein Y is selected from the group consisting of Ge, Si, As, B, or P, and n=2, 3/2 or 5/2.
13. The electrolyte of claim 12 , wherein the glass is chemically and electrochemically compatible in contact with lithium metal.
14. The electrolyte of claim 12 , wherein the glass is devoid of phosphorous.
15. The electrolyte of claim 1 , wherein the glass comprises Li 2 S and/or Li 2 O as a glass modifier and one or more of a glass former selected from the group consisting of P 2 S 5 , P 2 O 5 , SiS 2 , SiO 2 , B 2 S 3 and B 2 O 3 .
16. The electrolyte of claim 1 , wherein the electrolyte is disposed in a battery cell component as a separator adjacent a negative lithium electroactive layer.
17. The electrolyte of claim 1 , wherein the electrolyte is disposed in a battery cell as a separator between a positive electrode and a negative lithium electroactive layer.
18. A method of making a standalone Li-ion conductive solid electrolyte, the method comprising drawing a molten sheet of Li ion conducting sulfide glass into a freestanding inorganic vitreous sheet of sulfide-based lithium ion conducting glass.
19. The method of claim 18 , wherein the sulfide glass has a glass stability factor {Tx−Tg}<100° C.
20. The method of claim 18 , wherein the drawn freestanding inorganic vitreous sheet of sulfide-based lithium ion conducting glass has,
a liquid-like surface;
an area of at least 10 cm 2 ;
a thickness of no more than 100 μm; and
a room temperature intrinsic lithium ion conductivity of at least 10-5 S/cm.
21. A method of making a standalone Li-ion conductive solid electrolyte, the method comprising:
providing a Li ion conducting sulfide glass pre-form; and
pulling on the preform at a temperature sufficient to draw the pre-form to a vitreous glass ribbon having a thickness in the range of 5 μm to 100 μm.
22. The method of claim 21 , wherein the sulfide glass has a glass stability factor {Tx−Tg}<100° C.
23. The method of claim 21 , wherein the ribbon is a freestanding inorganic vitreous sheet of sulfide-based lithium ion conducting glass having,
a liquid-like surface;
an area of at least 10 cm 2 ;
a thickness of no more than 100 μm; and
a room temperature intrinsic lithium ion conductivity of at least 10 −5 S/cm.