SEPARATOR FOR LEAD ACID STORAGE BATTERY

摘要

A separator for a lead acid storage battery enabling the lead acid storage battery to infallibly have a predetermined capacity after the initial charging and a prolonged service life by limiting the maximum quantity of reducing substance liberated/produced from the separator at or below a given level. The separator is a porous membrane the main materials of which are a polyolefin resin, an inorganic power, and a mineral oil and the sub-material of which is a surfactant. The separator is characterized in that the mass of the reducing substance liberated/eluted after electrolization for 24 hours at about 25°C with a DC current of 1.2 A using an electrosis cell composed of the porous membrane, a positive electrode, a negative electrode, and a diluted sulfuric acid is 1.0 mL/100 cm<2> in terms of the corresponding value of the consumed quantity of N/100 potassium permanganate solution per 100 cm<2> of the porous membrane.