Sulfide and oxy-sulfide glass and glass-ceramic films for batteries incorporating metallic anodes

Abstract

A solid state electrolyte including an oxy-sulfide glass or glass ceramic, solid state electrolyte layer having a thickness in the range of ten micrometers to two hundred micrometers is provide. The composition of the electrolyte layer is the reaction product of a mixture initially including either a glass former including sulfur or a glass co-former including sulfur, and a glass modifier including Li2O or Na2O. The solid-state electrolyte layer is further characterized as having a wholly amorphous microstructure or as having small recrystallized regions separated from each other in an amorphous matrix, the recrystallized regions having a size of up to five micrometers. The solid-state electrolyte layer includes mobile lithium ions or mobile sodium ions associated with sulfur anions chemically anchored in the microstructure.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a divisional of U.S. patent application Ser. No. 15 / 480,505 filed on Apr. 6, 2017. The entire disclosure of the above application is incorporated herein by reference.TECHNICAL FIELD[0002]Methods are provided for preparing sulfide and oxy-sulfide glass and glass-ceramic solid-state electrolytes for batteries having a metallic anode substantially consisting of lithium or sodium. Dense sulfur-containing glasses are prepared which enable the formation of energy dense metal anode batteries while preventing penetration of metallic dendrites into the solid-state electrolyte / separator.INTRODUCTION[0003]Lithium batteries are finding increasing use in automotive vehicles and many other consumer products and sodium batteries are receiving favorable consideration for such applications. Exemplary batteries may employ a lithium metal anode in combination with a suitable liquid or solid electrolyte and a compatible active cathode mat...

AI Technical Summary

Benefits of technology

[0006]Sulfide and oxy-sulfide glasses may be formed by combining three classes of materials: i) one or more glass formers, including, for example, P2S5, SiS2, GeS2, SnS2, P2O5, B2O3, SiO2, Al2O3; ii) one or more glass modifiers, including, for example, Li2S, Na2S, Li2O, Na2O, and; iii) one or more dopants, for improving glass formability and / or stability, including, for example, LiI, Li3PO4, Li4SiO4. It will be understood that the compositions associated with particular material classes are exemplary and neither limiting nor exclusionary.

[0012]In an embodiment of the invention, an initial lithium-containing sulfide glass composition is in the form of small particles (a powder) having amorphous glassy microstructures. The particles are applied to a quartz substrate layer (or a like material resistant to moderate temperatures of less than about 350° C. and non-reactive with the glass particles) in a thin layer of generally uniform thickness and over an area predetermined for finished formation of the glass electrode / separator layers. The amorphous glass particles are then heated on, and consolidated against, the substrate to form a fully integral consolidated glass layer, 10 micrometers to 200 micrometers thick, still having a non-crystalline microstructure. The supported thin glass layer is then annealed to reduce any localized stresses induced in the consolidated microstructure and, if desired, to introduce small isolated crystal phases in the non-crystalline matrix.

[0014]The intention is to produce a thin, transparent to translucent, glass electrode / separator layer that can function cooperatively with a metallic lithium or sodium anode layer and efficiently accommodate the transport of lithium or sodium ions between the anode layer and an engaging, or nearby, cathode layer. Further, the thin glass layer remains resistant to penetration of metallic dendrites which may form on the anode during repeated cycling of the battery cell.

Problems solved by technology

Sulfide glasses have fair to excellent lithium ion conductivity but have been difficult to form as electrolyte / separator structures and have been vulnerable to cell failure due to penetration by lithium dendrites formed on and from the lithium anode during repeated cycling of the battery cell(s).

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