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 first frame comprises a first plate portion and a first support portion protruding from an upper surface of the first plate portion and supporting a side surface of the battery cells, and the second frame comprises a second plate portion and a second support portion protruding from a lower surface of the second plate portion and supporting the side surface of the battery cells.