Secondary Battery

A secondary battery is disclosed. According to one aspect of the present disclosure, there is provided a secondary battery comprising a cell assembly comprising battery cells, first and second frames coupled to the battery cells, and a case accommodating the battery cells and the first and second frames, and a housing in which one or more cell assemblies are accommodated, wherein the battery cells are combined with the first frame to form cell units and the cell units are connected to each other by the second frame.