Inorganic oxide powder, slurry containing same, nonaqueous electrolyte secondary battery, and method for manufacturing nonaqueous electrolyte secondary battery

Abstract

The present invention relates to an inorganic oxide powder which is suitably used to form an inorganic oxide porous film having excellent heat resistance, insulation properties and film strength, regardless of a small basis weight, and also having porosity capable of imparting sufficient ion permeability on at least one surface of a positive electrode, a negative electrode, or a separator that constitutes a nonaqueous electrolyte secondary battery. Disclosed is an inorganic oxide powder, wherein: 1) an average three-dimensional particle unevenness is 3.6 or more, and 2) an abundance ratio in number of particles having a particle diameter of less than 0.3 μm is 50% or more.

What is claimed is: 
     
         1 . An inorganic oxide porous film, wherein a proportion of a total of a pore volume inside coating film of pores inside coating film having a pore diameter inside coating film of 0.2 μm or less, relative to a total of a pore volume inside coating film of all pores inside coating film, is 35% or more. 
     
     
         2 . The inorganic oxide porous film according to  claim 1 , wherein the inorganic oxide porous film comprises an inorganic oxide powder having:
 1) an average three-dimensional particle unevenness of 3.6 or more, and   2) an abundance ratio in number of particles having a particle diameter of less than 0.3 μm of 50% or more.   
     
     
         3 . The inorganic oxide porous film according to  claim 1 , wherein the inorganic oxide is α alumina. 
     
     
         4 . The inorganic oxide porous film according to  claim 2 , wherein the inorganic oxide powder has a BET specific surface area of 6.0 m 2 /g or more. 
     
     
         5 . The inorganic oxide porous film according to  claim 1 , wherein the inorganic oxide porous film has a porosity of a range of 30 to 75%. 
     
     
         6 . A laminate, wherein: the inorganic oxide porous film according to  claim 1  is formed on a surface of a positive electrode, a negative electrode or a separator. 
     
     
         7 . A nonaqueous electrolyte secondary battery, wherein: the inorganic oxide porous film according to  claim 1  is formed on at least one surface of a positive electrode, a negative electrode or a separator. 
     
     
         8 . A laminated porous film, wherein: the inorganic oxide porous film according to  claim 1  is formed on a base material porous film.