Nonaqueous electrolytic secondary battery and method of manufacturing the same

Abstract

In a nonaqueous electrolytic secondary battery according to the invention, hexagonal system lithium containing cobalt composite oxide having a crystallite size in a (110) vector direction of 1000 Å or more and having a halogen compound added thereto by burning at time of synthesis is used as a positive electrode active material. By measuring a pH value of a filtrate obtained by dispersing, in water, the lithium containing cobalt composite oxide having the halogen compound added thereto by the burning at time of the synthesis and a crystallite size in the (110) vector direction of 1000 Å or more, a value of 9.6 to 10.1 is obtained. By using the lithium containing cobalt composite oxide as a positive electrode active material, a high temperature cycle property can be enhanced.

What is claimed is:  
     
         1 . A nonaqueous electrolytic secondary battery comprising a positive electrode active material capable of intercalating and deintercalating a lithium ion, a negative electrode active material capable of intercalating and deintercalating the lithium ion, and a nonaqueous electrolyte, 
 wherein the positive electrode active material is hexagonal system lithium containing cobalt composite oxide having a crystallite size in a (110) vector direction of 1000 Å or more and having halogen added thereto.    
     
     
         2 . The nonaqueous electrolytic secondary battery according to  claim 1 , wherein the halogen has a content of 0.001% by mass to 5.0% by mass for a mass of the positive electrode active material.  
     
     
         3 . The nonaqueous electrolytic secondary battery according to  claim 1 , wherein the hexagonal system lithium containing cobalt composite oxide having the halogen added thereto is lithium cobalt oxide having the halogen added thereto.  
     
     
         4 . The nonaqueous electrolytic secondary battery according to  claim 2 , wherein the hexagonal system lithium containing cobalt composite oxide having the halogen added thereto is lithium cobalt oxide having the halogen added thereto.  
     
     
         5 . The nonaqueous electrolytic secondary battery according to  claim 1 , wherein the hexagonal system lithium containing cobalt composite oxide having the halogen added thereto is lithium cobalt oxide having the halogen added thereto, having a part of cobalt substituted for at least one kind of heterogeneous element selected from V, Cr, Fe, Mn, Ni, Al and Ti, and having a molar ratio of the heterogeneous element to the cobalt of 0.0001 to 0.005.  
     
     
         6 . The nonaqueous electrolytic secondary battery according to  claim 2 , wherein the hexagonal system lithium containing cobalt composite oxide having the halogen added thereto is lithium cobalt oxide having the halogen added thereto, having a part of cobalt substituted for at least one kind of heterogeneous element selected from V, Cr, Fe, Mn, Ni, Al and Ti, and having a molar ratio of the heterogeneous element to the cobalt of 0.0001 to 0.005.  
     
     
         7 . The nonaqueous electrolytic secondary battery according to  claim 1 , wherein the halogen is fluorine.  
     
     
         8 . The nonaqueous electrolytic secondary battery according to  claim 4 , wherein the halogen is fluorine.  
     
     
         9 . The nonaqueous electrolytic secondary battery according to any of claims  6 , wherein the halogen is fluorine.  
     
     
         10 . A method of manufacturing a nonaqueous electrolytic secondary battery including a positive electrode active material capable of intercalating and deintercalating a lithium ion, a negative electrode active material capable of intercalating and deintercalating the lithium ion, and a nonaqueous electrolyte, comprising the steps of: 
 mixing a first component having a lithium compound, a second component having a cobalt compound, and a third component having a halogen compound to obtain a 3-component mixture; and    burning the 3-component mixture to have a crystallite size in a (110) vector direction of 1000 Å or more.    
     
     
         11 . The method of manufacturing a nonaqueous electrolytic secondary battery according to  claim 10 , wherein the halogen compound is added such that a content of a halogen component to a mass of the positive electrode active material is 0.001% by mass to 5.0% by mass.  
     
     
         12 . The method of manufacturing a nonaqueous electrolytic secondary battery according to  claim 10 , wherein the halogen compound is lithium fluoride.  
     
     
         13 . The method of manufacturing a nonaqueous electrolytic secondary battery according to  claim 11 , wherein the halogen compound is lithium fluoride.  
     
     
         14 . A method of manufacturing a nonaqueous electrolytic secondary battery including a positive electrode active material capable of intercalating and deintercalating a lithium ion, a negative electrode active material capable of intercalating and deintercalating the lithium ion, and a nonaqueous electrolyte, comprising the steps of: 
 mixing a first component having a lithium compound, a second component including a cobalt composite compound having a part of cobalt substituted for at least one kind of heterogeneous element selected from V, Cr, Fe, Mn, Ni, Al and Ti, and a third component having a halogen compound to obtain a 3-component mixture; and    burning the 3-component mixture to have a crystallite size in a (110) vector direction of 1000 Å or more.    
     
     
         15 . The method of manufacturing a nonaqueous electrolytic secondary battery according to  claim 14 , wherein the halogen compound is added such that a content of a halogen component to a mass of the positive electrode active material is 0.001% by mass to 5.0% by mass.  
     
     
         16 . The method of manufacturing a nonaqueous electrolytic secondary battery according to  claim 14 , wherein the halogen compound is lithium fluoride.  
     
     
         17 . The method of manufacturing a nonaqueous electrolytic secondary battery according to  claim 15 , wherein the halogen compound is lithium fluoride.  
     
     
         18 . A method of manufacturing a nonaqueous electrolytic secondary battery including a positive electrode active material capable of intercalating and deintercalating a lithium ion, a negative electrode active material capable of intercalating and deintercalating the lithium ion, and a nonaqueous electrolyte, comprising the steps of: 
 mixing a first component having a lithium compound, a second component having a cobalt compound, a third component having a compound containing at least one kind of element selected from V, Cr, Fe, Mn, Ni, Al and Ti, and a fourth component having a halogen compound to obtain a 4-component mixture; and    burning the 4-component mixture to have a crystallite size in a (110) vector direction of 1000 Å or more.    
     
     
         19 . The method of manufacturing a nonaqueous electrolytic secondary battery according to  claim 18 , wherein the halogen compound is added such that a content of a halogen component to a mass of the positive electrode active material is 0.001% by mass to 5.0% by mass.  
     
     
         20 . The method of manufacturing a nonaqueous electrolytic secondary battery according to  claim 18 , wherein the halogen compound is lithium fluoride.  
     
     
         21 . The method of manufacturing a nonaqueous electrolytic secondary battery according to  claim 19 , wherein the halogen compound is lithium fluoride.