Lithium ion battery and method for manufacturing the same

Abstract

A lithium ion secondary battery is disclosed that can inhibit generation of gas due to decomposition of a non-aqueous electrolyte solution. The lithium ion battery includes a cathode, a non-aqueous electrolyte solution and an anode, wherein the cathode includes a conductive material, a layered niobium-containing oxide that coats a surface of the conductive material, and a lithium-containing oxide active material having an upper-limit potential to a redox potential of metal lithium of no less than 4.5 V (vs. Li/Li + ).

What is claimed is: 
     
         1 . A lithium ion battery comprising:
 a cathode;   a non-aqueous electrolyte solution; and   an anode,   
       wherein the cathode includes a conductive material, a layered niobium-containing oxide that coats a surface of the conductive material, and a lithium-containing oxide active material having an upper-limit potential to a redox potential of metal lithium of no less than 4.5 V (vs. Li/Li + ). 
     
     
         2 . The lithium ion battery according to  claim 1 , wherein a thickness of the layered niobium-containing oxide is no less than 0.4 nm. 
     
     
         3 . The lithium ion battery according to  claim 2 , wherein the thickness of the layered niobium-containing oxide is in the range of from 0.4 nm to 5 nm. 
     
     
         4 . The lithium ion battery according to  claim 1 , wherein the conductive material consists of a carbon material. 
     
     
         5 . The lithium ion battery according to  claim 1 , wherein said niobium-containing oxide includes niobium oxide and lithium niobate. 
     
     
         6 . The lithium ion battery according to  claim 1 , wherein said lithium-containing oxide includes a lithium nickel manganese composite oxide. 
     
     
         7 . The lithium ion battery according to  claim 1 , wherein said conductive material is in a particulate form having a particle diameter of 5 nm to 100 nm and an aspect ratio of less than 2. 
     
     
         8 . The lithium ion battery according to  claim 1 , wherein said conductive material is in a fibrous form having a fiber diameter of 10 nm to 1 μm and has an aspect ratio of no less than 20. 
     
     
         9 . A method for manufacturing a lithium ion battery comprising:
 coating a surface of a conductive material with a layered niobium-containing oxide to form a complex;   mixing the complex and a lithium-containing oxide active material having an upper-limit potential to a redox potential of metal lithium of no less than 4.5 V (vs. Li/Li p ) to obtain a cathode mixture;   manufacturing a cathode from the cathode mixture; and   manufacturing a power generation element from the cathode, a non-aqueous electrolyte solution and an anode.   
     
     
         10 . The method according to  claim 9 , wherein the coating of the layered niobium-containing oxide is by an atomic layer deposition (ALD). 
     
     
         11 . The method according to  claim 9 , wherein said layered niobium-containing oxide has a thickness of in the range of no less than 0.4 nm. 
     
     
         12 . The method according to  claim 9 , wherein said layered niobium-containing oxide has a thickness in the range of 0.4 nm to 5 nm. 
     
     
         13 . The method according to  claim 9 , wherein the conductive material consists of a carbon material. 
     
     
         14 . The method according to  claim 9 , wherein said niobium-containing oxide includes niobium oxide and lithium niobate. 
     
     
         15 . The method accordingly to  claim 9 , wherein said lithium-containing oxide includes a lithium nickel manganese composite oxide. 
     
     
         16 . The method according to  claim 9 , wherein said conductive material is in a particulate form having a particle diameter of 5 nm to 100 nm and an aspect ratio of less than 2. 
     
     
         17 . The method according to  claim 9 , wherein said conductive material is in a fibrous form having a fiber diameter of 10 nm to 1 μm and has an aspect ratio of no less than 20.