Lithium-containing phosphates, methods of preparation, and uses thereof

Abstract

The invention provides an electrochemical cell which comprises a first electrode and a second electrode which is a counter electrode to said first electrode. The first electrode comprises a phosphorous compound of the nominal general formula Li 3 E′ a E″ b (PO 4 ) 3 , desirably at least one E is a metal; and preferably, Li 3 M′M″(PO 4 ) 3 . E′ and E″ are the same or different from one another, where at least one of E′ and E″ has more than one oxidation state.

What is claimed is:  
     
         1 . A mixture, comprising: 
 a compound represented by the nominal formula Li 3 V 2 (PO 4 ) 3 , and an electrically conductive diluent.    
     
     
         2 . The mixture of  claim 1 , wherein electrically conductive diluent is carbon.  
     
     
         3 . The mixture of  claim 1 , wherein electrically conductive diluent is carbon black.  
     
     
         4 . The mixture of  claim 3 , wherein the carbon black has a BET average surface area of 70±5 m 2 /gr.  
     
     
         5 . The mixture of  claim 1 , further comprising a binder.  
     
     
         6 . The mixture of  claim 5 , wherein the binder is selected from the group consisting of an ethylene propylene diene termonomer, polyvinylidene difluoride, an ethylene acrylic acid copolymer, and an ethylene vinyl acetate copolymer.  
     
     
         7 . The mixture of  claim 1 , wherein the compound has an XRD pattern corresponding to FIG. 6.  
     
     
         8 . An electrode, comprising: 
 an electrode active material represented by the nominal formula Li 3 V 2 (PO 4 ) 3 ; and    an electrically conductive diluent.    
     
     
         9 . The electrode of  claim 8 , wherein the electrically conductive diluent is carbon.  
     
     
         10 . The electrode of  claim 8 , wherein the electrically conductive diluent is carbon black.  
     
     
         11 . The electrode of  claim 10 , wherein the carbon black has a BET average surface area of 70±5 m 2 /gr.  
     
     
         12 . The electrode of  claim 10 , wherein the electrode comprises from 5 to 30% by weight carbon black.  
     
     
         13 . The electrode of  claim 8 , further comprising a binder.  
     
     
         14  The electrode of  claim 13 , wherein the binder is selected from the group consisting of an ethylene propylene diene termonomer, polyvinylidene difluoride, an ethylene acrylic acid copolymer, and an ethylene vinyl acetate copolymer.  
     
     
         15 . The electrode of  claim 13 , wherein the electrode comprises from 3 to 20% by weight binder.  
     
     
         16 . The electrode of  claim 8 , wherein the electrode active material has an XRD pattern corresponding to FIG. 6.  
     
     
         17 . A battery, comprising: 
 a first electrode comprising an electrode active material in a first condition represented by the nominal formula Li 3−x V 2 (PO 4 ) 3 , the first electrode further comprising an electrically conductive diluent;    a second electrode comprising an intercalation active material; and    an electrolyte;    wherein in the first condition x=0, and in a second condition 0<x≦3 and at least one V has an oxidation state higher than its oxidation state in the first condition.    
     
     
         18 . The battery of  claim 17 , wherein the electrically conductive diluent is carbon.  
     
     
         19 . The battery of  claim 17 , wherein the electrically conductive material is carbon black.  
     
     
         20 . The electrode of  claim 19 , wherein the carbon black has a BET average surface area of 70±5 m 2 /gr.  
     
     
         21 . The electrode of  claim 19 , wherein the electrode comprises from 5 to 30% by weight carbon black.  
     
     
         22 . The battery of  claim 17 , wherein the first electrode further comprises a binder.  
     
     
         23 . The battery of  claim 22 , wherein the binder is selected from the group consisting of an ethylene propylene diene termonomer, a polyvinylidene difluoride, an ethylene acrylic acid copolymer, and an ethylene vinyl acetate copolymer.  
     
     
         24 . The battery of  claim 22 , wherein the first electrode comprises from 3 to 20% by weight binder.  
     
     
         25 . The battery of  claim 17 , wherein the intercalation active material is selected from the group consisting of a transition metal oxide, a metal chalcogenide, carbon, graphite, and mixtures thereof.  
     
     
         26 . The battery of  claim 25 , wherein the second electrode comprises graphite.  
     
     
         27 . The battery of  claim 25 , wherein the electrically conductive diluent of the first electrode is carbon.  
     
     
         28 . The battery of  claim 25 , wherein the electrically conductive diluent of the first electrode is carbon black.  
     
     
         29 . The battery of  claim 28 , wherein the carbon black has a BET average surface area of 70±5 m 2 /gr.  
     
     
         30 . The battery of  claim 17 , wherein the electrode active material of the first electrode has an XRD pattern corresponding to FIG. 6.  
     
     
         31 . A method of making a lithium-vanadium-phosphate compound, comprising the steps of: 
 forming a mixture of a lithium-containing compound, at least one vanadium oxide compound, and a phosphoric acid-containing compound; and    heating the mixture at a temperature and for a time sufficient to form a lithium-vanadium-phosphate compound.    
     
     
         32 . The method of  claim 31 , wherein the lithium-containing compound is selected from the group consisting of lithium acetate, lithium hydroxide, lithium nitrate, and lithium carbonate.  
     
     
         33 . The method of  claim 31 , wherein the at least one vanadium oxide compound is selected from the group consisting of V 2 O 5  and V 2 O 3 .  
     
     
         34 . The method of  claim 31 , wherein the wherein the at least one vanadium oxide compound is V 2 O 3 .  
     
     
         35 . The method of  claim 31 , wherein the phosphoric acid-containing compound is ammonium phosphate.  
     
     
         36 . The method of  claim 31 , wherein the step of forming a mixture further comprises blending the mixture together with a solvent to form a wet mixture, wherein the wet mixture is heated at a temperature and for a time sufficient to form the lithium-vanadium-phosphate compound.  
     
     
         37 . The method of  claim 36 , wherein the solvent is selected from the group consisting of xylene and methanol.  
     
     
         38 . The method of  claim 36 , wherein the step of forming a mixture further comprises the steps of drying the wet mixture to form a dry mixture, and pressing the dry mixture into pellets, wherein the pellets are heated at a temperature and for a time sufficient to form the compound.  
     
     
         39 . The method of  claim 31 , wherein the step of heating the mixture further comprises heating the mixture in a non-oxidizing, reducing atmosphere.  
     
     
         40 . The method of  claim 39 , wherein the reducing atmosphere is a hydrogen atmosphere.  
     
     
         41 . The method of  claim 31 , wherein the lithium-vanadium-phosphate compound has an XRD pattern corresponding to FIG. 6.  
     
     
         42 . A method of making a compound represented by the nominal formula Li 3 V 2 (PO 4 ) 3 , comprising the steps of: 
 forming a mixture of a lithium-containing compound, at least one vanadium oxide compound, and a phosphoric acid-containing compound, in proportions to provide a compound represented by the nominal formula Li 3 V 2 (PO 4 ) 3 ; and    heating the mixture at a temperature and for a time sufficient to form the compound.    
     
     
         43 . The method of  claim 42 , wherein the lithium-containing compound is selected from the group consisting of lithium acetate, lithium hydroxide, lithium nitrate, and lithium carbonate.  
     
     
         44 . The method of  claim 42 , wherein the at least one vanadium oxide compound is selected from the group consisting of V 2 O 5  and V 2 O 3 .  
     
     
         45 . The method of  claim 42 , wherein the at least one vanadium oxide compound is V 2 O 3 .  
     
     
         46 . The method of  claim 42 , wherein the phosphoric acid-containing compound is ammonium phosphate.  
     
     
         47 . The method of  claim 42 , wherein the step of forming a mixture further comprises blending the mixture together with a solvent to form a wet mixture, wherein the wet mixture is heated at a temperature and for a time sufficient to form the lithium-vanadium-phosphate compound.  
     
     
         48 . The method of  claim 47 , wherein the solvent is selected from the group consisting of xylene and methanol.  
     
     
         49 . The method of  claim 47 , wherein the step of forming a mixture further comprises the steps of drying the wet mixture to form a dry mixture, and pressing the dry mixture into pellets, wherein the pellets are heated at a temperature and for a time sufficient to form the compound.  
     
     
         50 . The method of  claim 42 , wherein the step of heating the mixture further comprises heating the mixture in a non-oxidizing, reducing atmosphere.  
     
     
         51 . The method of  claim 50 , wherein the reducing atmosphere is a hydrogen atmosphere.  
     
     
         52 . The method of  claim 42 , wherein the compound has an XRD pattern corresponding to FIG. 6.  
     
     
         53 . A compound represented by the nominal formula Li 3 V 2 (PO 4 ) 3 , made by a process comprising the steps of: 
 forming a mixture of a lithium-containing compound, at least one vanadium oxide compound, and a phosphoric acid-containing compound, in proportions to provide a compound represented by the nominal formula Li 3 V 2 (PO 4 ) 3 ; and    heating the mixture at a temperature and for a time sufficient to form the compound.    
     
     
         54 . The compound of  claim 53 , wherein the lithium-containing compound is selected from the group consisting of lithium acetate, lithium hydroxide, lithium nitrate, and lithium carbonate.  
     
     
         55 . The compound of  claim 53 , wherein the at least one vanadium oxide compound is selected from the group consisting of V 2 O 5  and V 2 O 3 .  
     
     
         56 . The compound of  claim 53 , wherein the phosphoric acid-containing compound is ammonium phosphate.  
     
     
         57 . The compound of  claim 53 , wherein the step of forming a mixture further comprises blending the mixture together with a solvent to form a wet mixture, wherein the wet mixture is heated at a temperature and for a time sufficient to form the lithium-vanadium-phosphate compound.  
     
     
         58 . The compound of  claim 57 , wherein the solvent is selected from the group consisting of xylene and methanol.  
     
     
         59 . The compound of  claim 57 , wherein the step of forming a mixture further comprises the steps of drying the wet mixture to form a dry mixture, and pressing the dry mixture into pellets, wherein the pellets are heated at a temperature and for a time sufficient to form the compound.  
     
     
         60 . The compound of  claim 53 , wherein the step of heating the mixture further comprises heating the mixture in a non-oxidizing, reducing atmosphere.  
     
     
         61 . The compound of  claim 60 , wherein the reducing atmosphere is a hydrogen atmosphere.  
     
     
         62 . The compound of  claim 53 , wherein the compound has an XRD pattern corresponding to FIG. 6.