Panasonic Corporation

Ichiro Yasuoka

Masao Fukunaga

Kozo Watanabe

Toshiro Kume

An electrode in sheet form includes a current collector and an electrode mixture layer carried on each side thereof. The electrode is bent in the longitudinal direction thereof, to cause a large number of cracks in at least the electrode mixture layer to be positioned on the inner side of the current collector when wound, such that the cracks extend from the surface of the electrode mixture layer to the current collector in the direction intersecting with the longitudinal direction of the electrode. This bending process includes the steps of: bending the electrode at a curvature that is smaller than that of the winding core at least once; and thereafter bending the electrode at a curvature that is equal to or larger than that of the winding core. For example, this process is performed by arranging rollers such that their diameters decrease gradually and pressing the electrode against these rollers. This invention provides an electrode that does not break when wound to form an electrode assembly.

Growing community of inventors

Osaka, Japan

Ichiro Yasuoka