Secondary battery and electrode production method

Abstract

Secondary battery includes a battery assembly configured by alternately stacking positive electrodes 1 and negative electrodes 6 via separators 20, in which the positive electrode and the negative electrode respectively include collectors 3 and 8, and active materials 2 and 7 applied on the collectors. On each surface of the collector, a coated portion coated with the active material and an uncoated portion not coated with any active material are provided. In one or both of the positive electrode and the negative electrode, boundary portion 4 a between the coated portion and the uncoated portion on the front surface of the collector, is positioned planarly away from boundary portion 4 b between the coated portion and the uncoated portion on the rear surface of the collector.

1 . A production method of electrode for a secondary battery in which the electrodes are stacked with a separator interposed the electrodes, comprising:
 providing a coated portion coated with the active material and an uncoated portion not coated with the active material along a longitudinal direction so that the coated portion and the uncoated portion are adjacent to each other, by continuously applying an active material on a collector;   arranging a boundary portion between the coated portion and the uncoated portion on front or rear surface of the collector at a position not facing a boundary portion between the coated portion and the uncoated portion on the other front or rear surface; and   providing an insulating member which covers the boundary portion between the coated portion and the uncoated portion.   
     
     
         2 . The production method of the electrodes according to  claim 1 , further comprising arranging a double-side coated portion in which the active material is applied on both sides of the collector, a one-side coated portion in which the active material is applied on front or rear surface of the collector and in which the active material is not applied on the other front or rear surface, and a double-side uncoated portion in which the active material is not applied on the both sides of the collector, side by side in the longitudinal direction of the electrodes.