Aqueous electrolyte lithium sulfur batteries

Abstract

Provided are lithium sulfur battery cells that use water as an electrolyte solvent. In various embodiments the water solvent enhances one or more of the following cell attributes: energy density, power density and cycle life. Significant cost reduction can also be realized by using an aqueous electrolyte in combination with a sulfur cathode. For instance, in applications where cost per Watt-Hour (Wh) is paramount, such as grid storage and traction applications, the use of an aqueous electrolyte in combination with inexpensive sulfur as the cathode active material can be a key enabler for the utility and automotive industries, providing a cost effective and compact solution for load leveling, electric vehicles and renewable energy storage.

What is claimed is: 
     
         1 . An aqueous lithium sulfur electrochemical cell, comprising:
 an anode structure comprising a lithium electroactive material;   a cathode comprising a solid electron transfer medium;   an aqueous electrolyte comprising a non-aqueous solvent in direct contact with the electron transfer medium; and   active sulfur species in direct contact with the aqueous electrolyte;   wherein the anode electroactive material is isolated from direct contact with the aqueous electrolyte whereby the anode electroactive material does not contact water of the aqueous electrolyte or the active sulfur species.