Abstract: A battery rack effectively prevents the spread of a fire or heat to adjacent battery packs when the fire or thermal runaway occurs in any of a plurality of battery packs. To achieve the above-described object, the battery rack includes a plurality of battery packs; and a rack case having a receiving space with an open structure in which the plurality of battery packs is vertically mounted at intervals and placed in vertical communication with one another, wherein a stopper is provided in the receiving space and disposed between the plurality of battery packs, spaced apart from the plurality of battery packs, and is configured to suppress volume expansion of the battery pack when the volume of the battery pack expands.

Abstract: A battery module includes a plurality of battery cells assemblies, each having a plurality of battery cells stacked on each other; and at least one cooling unit provided between the plurality of battery cells assemblies and filled with a predetermined coolant therein, the at least one cooling unit having at least one membrane member provided at one end thereof to be opened or closed according to a change of an internal pressure thereof.

Abstract: A cylindrical secondary battery includes a first gasket and a second gasket having a modified shape to secure hermetic sealability and insulation. The battery includes a cylindrical can for receiving an electrode assembly, a cap assembly located at the upper part of the cylindrical can, a first gasket for covering outer circumferential edges of a top cap and a venting member of the cap assembly, a current interrupt device (CID) located at the lower part of the cap assembly, and a second gasket along the outer circumferential edge of the current interrupt device. An upper end portion of the first gasket covers the upper surface of the outer circumferential edge of the top cap, and includes a recessed portion in its inner surface configured to prevent the first gasket from being brought into tight contact with the upper surface of the outer circumferential edge of the top cap.