| 摘要 |
PROBLEM TO BE SOLVED: To provide a fine fiber structure which is good in ion permeability and short circuit resistance, excellent in capacity retention at a high rate, and suitable as a separator or an insulation material for a battery, an electric double layer capacitor, and a capacitor.SOLUTION: A fine fiber structure includes a porous fine fiber layer comprising polymer fine fibers having an average diameter of 50 to 3000 nm. The porous fine fiber layer has a residual solvent quantity of less than 0.1 wt%, an average pore diameter of 0.01 to 15 μm, a thickness of 0.0025 to 0.3 mm, a porosity of 20 to 90%, a basis weight of 1 to 90 g/m, a Frazier air permeability of less than 46 m/min/m, and a Macmillan number of 2 to 15. |
