Battery module, battery pack and vehicle including the same

A battery module comprising:

• a battery cell assembly having at least one battery cell;
• a module case accommodating the battery cell assembly and including a first cover plate covering a first side of the battery cell assembly and a second cover plate covering a second side of the battery cell assembly, the second side of the battery cell assembly being different from the first side of the battery cell assembly;
• and
• at least one bolting member integrally fastened through the first cover plate and the second cover plate of the module case,
• wherein each bolting member includes a first portion fastened to the first cover plate and a second portion fastened to the second cover plate, and
• wherein the first and second portions of each bolting member have different diameters.