A battery electric vehicle includes a pair of spaced apart and substantially parallel longitudinal members and a floor pan coupled to and above at least a portion of the longitudinal members. A battery pack bay is defined below the floor pan, longitudinally between predefined front and rear limits, and laterally between the longitudinal members. A battery pack may be upwardly disposed within the battery pack bay, the battery pack including a pair of laterally spaced apart sides whereat the first battery pack is removably attached to the respective longitudinal members. The battery pack may be dimensioned longitudinally to occupy less than the entire longitudinal space of the battery pack bay. A closeout structure may be removably attached to the respective longitudinal members and one longitudinal end of the first battery pack.