SEPARATOR FOR ELECTROCHEMICAL ELEMENTS, AND ELECTROCHEMICAL ELEMENT

A separator for electrochemical elements is formed of beaten regenerated cellulose fibers and capable of withstanding a common element winding process for an aluminum electrolytic capacitor, while having denseness and low impedance characteristics. The separator is interposed between a pair of electrodes, while capable of holding an electrolyte solution that contains an electrolyte, is configured from a single layer so as to have a thickness of 10 to 35 μm, a density of 0.35 to 0.80 g/cm, a tensile strength of 9.8 N/15 mm or more, an average pore diameter of 0.05 to 1.00 μm, and a modified tensile strength of 5.9 N/15 mm or more, if the value of a tensile strength as measured by setting the distance between holders of a tensile testing machine to 0.1 mm and the elongation rate of a test piece to 200 mm/min is defined as the modified tensile strength.