Abstract: Provided is a separator which can make the electric field on the surface of a negative electrode for a metal secondary battery homogeneous to thereby prevent the formation of dendrites. A porous separator for metal secondary batteries, which has a polymer electrolyte layer formed on the surface layer of at least one main surface of a porous polyimide film. It is preferred that the polymer electrolyte layer is composed of both a polymer electrolyte material which is supported on at least one main surface of the porous polyimide film and a polymer electrolyte material which is supported in voids in a layered region that extends from the main surface.

Abstract: A method for manufacturing, a secondary battery separator including a porous resin film in which pores have three-dimensionally ordered structure and are in mutual communication via through-holes. The method includes: uniformly dispersing spherical microparticles having narrow particle size distribution in a dispersion medium to prepare a microparticles-dispersed slurry; drying slurry to obtain a spherical microparticles-dispersed film; heat-treating the film to form a microparticles-resin film in which the microparticles are regularly arrayed in three-dimensions in a resin matrix; and contacting the microparticles-resin film with an organic acid, water, an alkaline solution or an inorganic acid other than hydrofluoric acid to dissolve and remove the microparticles, or heating the microparticles-resin film to remove the microparticles, to form pores which are in mutual communication and regularly arrayed in the resin matrix.

Abstract: A lithium secondary battery having a positive electrode, a negative electrode, a separator and an electrolyte solution, in which the positive electrode contains a first active material and a second active material each capable of intercalating and deintercalating lithium. The first active material is in the state under which only deintercalation of lithium can be carried out in a battery reaction with the negative electrode immediately after assembly of the lithium secondary battery, and the second active material is in the state under which lithium can be intercalated in the battery reaction with the negative electrode immediately after assembly of the lithium secondary battery. The negative electrode contains metal lithium as an active material. The separator has a structure in which pores are three-dimensionally regularly arranged.

Abstract: Provided is a separator which can make the electric field on the surface of a negative electrode for a metal secondary battery homogeneous to thereby prevent the formation of dendrites. A porous separator for metal secondary batteries, which has a polymer electrolyte layer formed on the surface layer of at least one main surface of a porous polyimide film. It is preferred that the polymer electrolyte layer is composed of both a polymer electrolyte material which is supported on at least one main surface of the porous polyimide film and a polymer electrolyte material which is supported in voids in a layered region that extends from the main surface.

Abstract: A method for manufacturing, a secondary battery separator including a porous resin film in which pores have three-dimensionally ordered structure and are in mutual communication via through-holes. The method includes: uniformly dispersing spherical microparticles having narrow particle size distribution in a dispersion medium to prepare a microparticles-dispersed slurry; drying slurry to obtain a spherical microparticles-dispersed film; heat-treating the film to form a microparticles-resin film in which the microparticles are regularly arrayed in three-dimensions in a resin matrix; and contacting the microparticles-resin film with an organic acid, water, an alkaline solution or an inorganic acid other than hydrofluoric acid to dissolve and remove the microparticles, or heating the microparticles-resin film to remove the microparticles, to form pores which are in mutual communication and regularly arrayed in the resin matrix.