BATTERY AND MANUFACTURING METHOD THEREOF

A battery is provided which can attain a high space efficiency in a battery case, and is excellent in insertability of a wound electrode body into the battery case during manufacturing. The battery herein disclosed includes a rectangular battery case and a wound electrode body including an electrode. The electrode has a long collector and mixture material layers. The electrode has alternately flat first surfaces stacked in the main surface direction of the wound electrode body and second surfaces stacked in the side surface direction of the wound electrode body. A thickness ratio B/A is 0.1 or less, where A represents an average thickness of the mixture material layers present on the first surfaces and B represents an average thickness of the mixture material layers present on the second surfaces.