| 摘要 |
This invention provides a composite material for use as an electrode in electrochemical devices. An electroactive composite material includes a first electroactive metal, the electroactive material including a phase enriched in a metal or metal alloy, MeI, capable of intercalating or alloying with a species selected from the group consisting of alkali metals and hydrogen, and a second material having the first active material intimately mixed therein. The second material includes a metal oxide, MeyIIOz, wherein the metals MeI have a less negative Gibbs free energy for alloying or compound formation with oxygen than the metals that comprise MeIIO. The materials of the invention comprise a first material that is an elemental metal, metal alloy, metal oxide, or other metal compound, selected so that it is able to alloy with lithium, and prepared in a dispersed one-, two- or three-dimensional form. The first material is intimately mixed with or dispersed within a second material that may be substantially conductive to electrons or electron holes or lithium ions. The composite material may be prepared by a process known as "partial reduction" or "internal reduction," in which a precursor to the first material is preferentially reduced, or the process known as "partial oxidation," in which a precursor to the second material is preferentially oxidized.
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