Electrode protection in both aqueous and non-aqueous electrochemical cells, including rechargeable lithium batteries

Abstract

Electrode protection in electrochemical cells, and more specifically, electrode protection in both aqueous and non-aqueous electrochemical cells, including rechargeable lithium batteries, are presented. In one embodiment, an electrochemical cell includes an anode comprising lithium and a multi-layered structure positioned between the anode and an electrolyte of the cell. A multi-layered structure can include at least a first single-ion conductive material layer (e.g., a lithiated metal layer), and at least a first polymeric layer positioned between the anode and the single-ion conductive material. The invention also can provide an electrode stabilization layer positioned within the electrode to control depletion and re-plating of electrode material upon charge and discharge of a battery. Advantageously, electrochemical cells described herein are not only compatible with environments that are typically unsuitable for lithium, but the cells may be also capable of displaying long cycle life, high lithium cycling efficiency, and high energy density.

What is claimed is:  
     
         1 . An anode for use in an electrochemical cell, comprising:
 a first electroactive layer comprising an active electrode species;   a second electroactive layer comprising the active electrode species, wherein the anode is adapted and arranged such that when the anode is present in an electrochemical cell, at least some of the active electrode species in the second electroactive layer is depleted upon discharge of the electrochemical cell; and   a protective structure comprising a polymeric material and/or an ion conductive material, wherein the protective structure separates the first electroactive layer from the second electroactive layer.   
     
     
         2 . An anode for use in an electrochemical cell, comprising:
 a first electroactive layer comprising an active electrode species;   a second electroactive layer comprising the active electrode species, wherein the anode is adapted and arranged such that when the anode is present in an electrochemical cell, at least some of the active electrode species in the second electroactive layer is depleted upon discharge of the electrochemical cell; and   a polymer layer and/or an ion conducting layer separating the first electroactive layer from the second electroactive layer, wherein most or all of the second electroactive layer is formed from the active electrode species.   
     
     
         3 . An anode as in  claim 1 , wherein the protective structure comprises the polymeric material. 
     
     
         4 . An anode as in  claim 1  wherein the protective structure comprises the ion conductive material. 
     
     
         5 . An anode as in  claim 1 , wherein the protective structure comprises a composite of the ion conductive material and the polymeric material. 
     
     
         6 . An anode as in  claim 5 , wherein the polymeric material is conductive to lithium ions. 
     
     
         7 . An anode as in  claim 5 , wherein the polymeric material comprises a lithium salt. 
     
     
         8 . An anode as in  claim 5 , wherein the polymeric material is substantially non-conductive to lithium ions. 
     
     
         9 . An anode as in  claim 1 , comprising a second protective structure positioned adjacent the second electroactive layer, wherein the second protective structure comprises a polymeric material and/or an ion conductive material. 
     
     
         10 . An anode as in  claim 9 , wherein at least one of the first and second protective structures comprises a polymer layer comprising the polymeric material, and the polymer layer is no greater than 0.5 microns thick. 
     
     
         11 . An anode as in  claim 9 , wherein at least one of the first and second protective structures comprises a polymer layer comprising the polymeric material, and the polymer layer is no greater than 0.1 microns thick. 
     
     
         12 . An anode as in  claim 9 , wherein at least one of the first and second protective structures comprises an ion conductive layer comprising the ion conductive material, and wherein the ion conductive layer has a thickness of less than about 500 nanometers. 
     
     
         13 . An anode as in  claim 9 , wherein at least one of the first and second protective structures comprises an ion conductive layer comprising the ion conductive material, and wherein the ion conductive layer has a thickness of less than about 50 nanometers. 
     
     
         14 . An anode as in  claim 12 , wherein the ion conductive layer comprises a ceramic conductive to lithium ions. 
     
     
         15 . An anode as in  claim 12 , wherein the ion conductive layer comprises lithium nitride. 
     
     
         16 . An anode as in  claim 12 , wherein the ion conductive layer comprises lithium oxide. 
     
     
         17 . An anode as in  claim 12 , wherein the ion conductive layer comprises pores and at least a portion of the pores are filled with a polymer. 
     
     
         18 . An anode as in  claim 12 , wherein at least one of the first and second protective structures is a multi-layered protective structure comprising alternating ion conductive layer(s) and polymer layer(s). 
     
     
         19 . An anode as in  claim 9 , wherein at least one of the first and second protective structures has a thickness of less than 1 mm. 
     
     
         20 . An anode as in  claim 1 , wherein most or all of the second electroactive layer is formed from the active electrode species. 
     
     
         21 . An anode as in  claim 1 , wherein at least one of the first and second electroactive layers comprises metallic lithium. 
     
     
         22 . An anode as in  claim 1 , wherein the thickness of the anode is in the range of about 5 to 50 microns. 
     
     
         23 . An anode as in  claim 1 , wherein each of the first and second electroactive layers is a lithium metal layer or a lithium metal alloy layer.