Battery, and battery pack and vehicle comprising the same

A battery includes an electrode assembly including a first electrode, a second electrode and a separator between the first electrode and the second electrode wound around a winding axis to define a core and an outer circumferential surface, the first electrode including a first uncoated region in which an active material layer is not coated along a winding direction; a housing accommodating the electrode assembly through an open portion at a lower end thereof; a first current collector coupled to the first uncoated region and disposed in the housing; a cap to cover the open portion; and a spacer between the first current collector and the cap and having a height corresponding to a distance between the first current collector and the cap.