A battery lid is formed of a metal plate integrally formed with a valve and a surrounding plate portion surrounding the valve which facilitates rupturing the valve at a predetermined pressure. The valve includes a pressure receiving plate portion having a bending groove, and bendable from the bending groove by applied pressure, and a thin plate portion thinner than the thickness of the surrounding plate portion, and connects the pressure receiving plate portion to the surrounding plate portion. The thin plate portion has a rupture groove passing through extension sections on the respective lines extending from the bending groove. As the pressure receiving plate portion is deformed by the pressure applied to the valve, the extension sections are pulled more strongly than are the other sections in the valve. Therefore, when a predetermined pressure is applied, the valve is ruptured from the extension sections of the rupture groove.

A battery lid is formed of a metal plate integrally formed with a valve and a surrounding plate portion surrounding the valve which facilitates rupturing the valve at a predetermined pressure. The valve includes a pressure receiving plate portion having a bending groove, and bendable from the bending groove by applied pressure, and a thin plate portion thinner than the thickness of the surrounding plate portion, and connects the pressure receiving plate portion to the surrounding plate portion. The thin plate portion has a rupture groove passing through extension sections on the respective lines extending from the bending groove. As the pressure receiving plate portion is deformed by the pressure applied to the valve, the extension sections are pulled more strongly than are the other sections in the valve. Therefore, when a predetermined pressure is applied, the valve is ruptured from the extension sections of the rupture groove.

A power storage module includes an array including power storage devices each having first and second surfaces opposite to each other in a first direction, a first restraint member facing the first surface of each power storage device, and a second restraint member facing the second surface of each power storage device. Dimensions of the power storage devices in a second direction perpendicular to the first direction are larger than respective dimensions of the power storage devices. The power storage devices are arranged in a third direction perpendicular to the first and second directions. The first restraint member extends in the third direction and restrains the array in the third direction. The second restraint member extends in the third direction and restrains the array in the third direction. At least one of the first and second restraint members has a hole therein. The hole is a recess falling in the first direction or a through-hole passing through the restraint member in the first direction.

A power storage module includes an array including power storage devices each having first and second surfaces opposite to each other in a first direction, a first restraint member facing the first surface of each power storage device, and a second restraint member facing the second surface of each power storage device. Dimensions of the power storage devices in a second direction perpendicular to the first direction are larger than respective dimensions of the power storage devices. The power storage devices are arranged in a third direction perpendicular to the first and second directions. The first restraint member extends in the third direction and restrains the array in the third direction. The second restraint member extends in the third direction and restrains the array in the third direction. At least one of the first and second restraint members has a hole therein. The hole is a recess falling in the first direction or a through-hole passing through the restraint member in the first direction.

A power storage device includes a case, a power storage element disposed in the case, a lead connected to an electrode of the power storage element, a sealing member sealing an opening of the case. The sealing member includes a gasket and a sealing plate having conductivity. The gasket includes a base having a disk shape. The base is disposed between the sealing plate and the power storage element. The base has a through-hole formed therein. The sealing plate includes a protrusion inserted in the through-hole. The protrusion of the sealing plate is connected to the lead. The protrusion is configured to be displaced in a direction away from the lead in accordance with an increase of an internal pressure of the case so as to be disconnected from the lead.

A power storage device includes a case, a power storage element disposed in the case, a lead connected to an electrode of the power storage element, a sealing member sealing an opening of the case. The sealing member includes a gasket and a sealing plate having conductivity. The gasket includes a base having a disk shape. The base is disposed between the sealing plate and the power storage element. The base has a through-hole formed therein. The sealing plate includes a protrusion inserted in the through-hole. The protrusion of the sealing plate is connected to the lead. The protrusion is configured to be displaced in a direction away from the lead in accordance with an increase of an internal pressure of the case so as to be disconnected from the lead.

A battery housing includes at least one membrane-like degassing element which is designed to yield when a hot gas of the at least one battery cell is released into an interior of the battery housing, and in so doing to open up a degassing opening in the housing wall for discharging the hot gas from the interior to an area surrounding the battery housing, and at least one protective cap which, for protecting the at least one degassing element against environmental influences, is arranged on an outer side of the housing wall in a manner overlapping the at least one degassing element and which is fastened to the housing wall by way of a holding device, wherein the holding device is designed to yield, and to completely release the protective cap from the degassing opening, when the hot gas is discharged via the at least one degassing element.

Provided is a secondary battery including an electrode assembly and an outer case configured to house the electrode assembly. The secondary battery includes a terminal member provided on the outer case with an insulating material interposed therebetween and connected to a tab of the electrode assembly. The outer case is provided with a cavity through which the tab passes, the terminal member is bonded onto a surface of the outer case with the insulating material interposed therebetween, the surface being positioned around the cavity, and a part of a width dimension of a bonding region provided to surround the cavity for the bonding is reduced.

Provided is a secondary battery including an electrode assembly and an outer case configured to house the electrode assembly. The secondary battery includes a terminal member provided on the outer case with an insulating material interposed therebetween and connected to a tab of the electrode assembly. The outer case is provided with a cavity through which the tab passes, the terminal member is bonded onto a surface of the outer case with the insulating material interposed therebetween, the surface being positioned around the cavity, and a part of a width dimension of a bonding region provided to surround the cavity for the bonding is reduced.

A battery pack includes: a plurality of battery modules; a venting inducing frame disposed along an edge of the battery modules and forming a venting passage; a venting gate for connecting an inside of the battery modules and the venting inducing frame; a rupture portion formed on an outside of the venting inducing frame; and a unidirectional valve formed on a passage of the venting inducing frame, wherein the unidirectional valve intercepts a passage in a direction connected to a venting gate connected to a second battery module from the venting gate connected to one battery module from among the battery modules, and opens a passage in a direction connected to the rupture portion from the venting gate connected to one battery module from among the battery modules.