Abstract: Disclosed is a method for pre-detecting a defective porous polymer substrate for a separator, including selecting a porous polymer substrate having a plurality of pores; observing the selected porous polymer substrate with a scanning electron microscope (SEM) to obtain an image of the porous polymer substrate; quantifying the average value of pore distribution index (PDI); correcting the quantified average value of pore distribution index to obtain the corrected average value of pore distribution index; determining whether or not the corrected average value of pore distribution index is 60 a.u. (arbitrary unit) or less; and classifying the porous polymer substrate as a good product, when the corrected average value of pore distribution index is determined to be 60 a.u. or less, and classifying the porous polymer substrate as a defective product, when the corrected average value of pore distribution index is determined to be larger than 60 a.u.

Abstract: A branching device for enclosing a hybrid fan-out cable the hybrid fan-out cable comprising plural optical cables and power cables, the branching device includes: an enclosure having a first end, through which the hybrid fan-out cable is inserted, and a second end that is opened; and a gasket provided at the second end of the enclosure and having plural through-holes; and a cover thread-coupled to the second end of the enclosure to fasten the gasket to the second end of the enclosure in such a manner that the through-holes are exposed. In the enclosure, the hybrid fan-out cable is branched out into plural individual sub-part cable components, and each of the sub-part cable components is drawn out through one of the through-holes of the gasket to the outside. The gasket is formed from an elastic material which forms a tight seal between the inner peripheral surface of the enclosure and with the outer peripheral surface of each of the sub-part cable components to seal the other end of the enclosure.