Disclosed is a positive electrode plate (2) which comprises: a double side coated part (14) in which an active material layer (13) and a porous protective film (28) are formed on the both surfaces of a collector core material (12); a core material exposed part (18); and a single side coated part (17) which is positioned between the double side coated part (14) and the core material exposed part (18) and in which the active material layer (13) and the porous protective film (28) are formed on one surface of the collector core material (12). The double side coated part (14) is provided with a plurality of grooves (10), but the single side coated part (17) is not provided with a groove (10). The grooves (10) are so formed as to extend from the surface of the porous protective film (28) to the surface of the active material layer (13). A collector lead (20) of the positive electrode is connected to the core material exposed part (18), and the positive electrode plate (2) is rolled up in such a manner that the core material exposed part (18) makes the roll end.