Electrolyte materials for use in electrochemical cells

Abstract

Electrolyte materials for use in electrochemical cells, electrochemical cells comprising the same, and methods of making such materials and cells, are generally described. In some embodiments, the materials, processes, and uses described herein relate to electrochemical cells comprising sulfur and lithium such as, for example, lithium sulfur batteries. The electrolyte can comprise a polymeric material and, in some cases, an absorbed auxiliary material. For example, the electrolyte material can be capable of forming a gel, and the auxiliary material can comprise an electrolyte solvent. In some instances, the electrolyte material can comprise at least one organic (co)polymer selected from polyethersulfones. The non-fluid material in the electrolyte, when configured for use, can, alone or in combination with the optional absorbed auxiliary material, have a yield strength greater than that of lithium metal, in some embodiments. In some embodiments, the electrochemical cell (e.g., the electrolyte) can be configured such that the electrochemical cell can be cycled at relatively high temperatures without experiencing thermal runaway.

Description

RELATED APPLICATIONS[0001]This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No. 61 / 376,559, filed Aug. 24, 2010, and entitled “Electrolyte Materials for Use in Electrochemical Cells,” which is incorporated herein by reference in its entirety for all purposes.FIELD OF INVENTION[0002]Electrolyte materials for use in electrochemical cells, electrochemical cells comprising the same, and methods of making such materials and cells are generally described. In some embodiments, the materials, processes, and uses described herein relate to electrochemical cells comprising sulfur and lithium such as, for example, lithium sulfur batteries.BACKGROUND[0003]Lithium compound containing electric cells and batteries containing such cells are modern means for storing energy. They exceed conventional secondary batteries with respect to capacity and life-time and, in many times, use of toxic materials such as lead can be avoided. However, in contrast t...

AI Technical Summary

Benefits of technology

The present invention provides electrolyte materials for use in electrochemical cells, methods of making such materials and cells, and uses of the materials and cells. The electrolyte materials comprise a sulfur-containing electrode, a lithium or lithium alloy electrode, and a gel-state polyethersulfone organic polymer. The electrolyte also includes an organic solvent and a salt of lithium. The electrochemical cells comprising these materials have a yield strength greater than that of lithium metal and can be used at temperatures up to about 130°C without experiencing thermal runaway. The invention also provides methods for making the electrodes and using the cells.

Problems solved by technology

However, in contrast to conventional lead-based secondary batteries, various technical problems have not yet been solved.

Although the batteries mentioned therein exhibit advantageous features, they are limited in capacity.

A particular problem with lithium sulfur batteries is the thermal runaway which can be observed at elevated temperatures between, e.g., 150 to 230° C. and which leads to complete destruction of the battery.

However, those methods usually lead to a dramatic reduction in capacity.

However, the thermal runaway problem has not been solved satisfactorily.

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