BATTERY PACK

A battery pack includes a plurality of rectangular secondary batteries arranged in a state in which the plurality of rectangular secondary batteries is pressed against each other in an arrangement direction through spacers. Each rectangular secondary battery is configured such that a flat wound electrode body is housed in a battery case with a winding axis extending parallel with a long side surface of the battery case. The electrode body has a flat portion in which positive and negative electrode material mixture layers face each other with a separator interposed therebetween. The spacers include a pair of first pressing portions pressing both end portions of the long side surface, which faces the flat portion, of the battery case in a winding axis direction along a direction perpendicular to the winding axis, and a second pressing portion pressing a portion of the long side surface along the winding axis between the pair of first pressing portions.