Battery pack

A battery pack comprising:

• a plurality of unit cells and at least one spacer, wherein
• the plurality of unit cells and the at least one spacer are alternately arranged in an arrangement direction and a load is applied in the arrangement direction;
• each unit cell of the plurality of unit cells comprises:
• an electrode body having a positive electrode and a negative electrode;
• and
• a battery case accommodating the electrode body and having a pair of long side surfaces, at least one of the pair of the long side surfaces of the battery case facing the at least one spacer;
• the electrode body has, along a direction in which the pair of long side surfaces of the battery case are arranged, a reaction section in which the positive electrode and the negative electrode are laminated in the arrangement direction in an insulated state;
• the at least one spacer includes, on a surface thereof facing a long side surface of the pair of long side surfaces of the battery case, a first pressing portion that presses a first part of the reaction section in the arrangement direction;
• the first part of the reaction section of which the first pressing portion presses includes
• a first center portion and a pair of end portions, each extending in a width direction of the long side surface of the pair of long side surfaces of the battery case, which is orthogonal to a vertical direction of the long side surface of the pair of long side surfaces of the battery case,
• the first pressing portion presses each of the first center portion and the pair of end portions of the reaction section along an entire height of these respective portions in the vertical direction of the long side surface of the pair of long side surfaces of the battery case;
• and
• the first pressing portion does not press a lower region of the reaction section, the lower region of the reaction section including ⅓ of an entire height of the reaction section, as measured from a lower end of the reaction section to an upper end of the reaction section in the vertical direction of the long side surface of the pair of long side surfaces of the battery case, and the lower region of the reaction section extending over a length of ½ or more of an entire length of the reaction section in the width direction of the long side surface of the pair of long side surfaces of the battery case.