An end cover assembly includes: an end cover with a through hole for injecting electrolyte and a first clamping portion, wherein the first clamping portion is disposed along a circumferential direction of the through hole and is located on one side of the end cover away from an interior of the battery cell; a sealing ring for sealing the through hole; and a pressure relief device covering at least part of the sealing ring and closing the through hole; wherein the pressure relief device includes a second clamping portion, and is rotatable such that when the pressure relief device is rotated to a first position, the second clamping portion is clamped with the first clamping portion; and when the pressure relief device is rotated to a second position, the second clamping portion is disengaged from the first clamping portion.

A pressure balancing device comprises a mounting seat, a breathable film and a drying component. The mounting seat comprises a mounting seat housing and a support portion connected to the mounting seat housing. A fluid channel is formed in the mounting seat housing, the support portion is disposed in the fluid channel, and the fluid channel is capable of fluidly communicating an interior space of a component to be depressurized with the external environment. The breathable film covers on the fluid channel. The drying component is disposed on the support portion and is located between the support portion and the breathable film, and the drying component is configured to absorb moisture entering the fluid channel. In the present disclosure, the drying component is provided inside of the breathable film of the pressure balancing device, and water vapor entering the pressure balancing device is absorbed by the drying component.

A pressure balancing device comprises a mounting seat, a breathable film and a drying component. The mounting seat comprises a mounting seat housing and a support portion connected to the mounting seat housing. A fluid channel is formed in the mounting seat housing, the support portion is disposed in the fluid channel, and the fluid channel is capable of fluidly communicating an interior space of a component to be depressurized with the external environment. The breathable film covers on the fluid channel. The drying component is disposed on the support portion and is located between the support portion and the breathable film, and the drying component is configured to absorb moisture entering the fluid channel. In the present disclosure, the drying component is provided inside of the breathable film of the pressure balancing device, and water vapor entering the pressure balancing device is absorbed by the drying component.

A venting device is provided at one side of a battery pack to discharge a venting gas generated in an inner space of the battery pack to the outside. The venting device includes a cylinder block configured to communicate with the inside of the battery pack and a venting gas flow path for discharging the venting gas to the outside, a piston assembly configured to move upward along an extension direction of the cylinder block by receiving a force caused by the increase of the internal pressure of the battery pack so that the inner space of the battery pack communicates with the venting gas flow path and a magnet unit installed in the cylinder block and configured to restrict upward movement of the piston assembly by a magnetic force so that the communication between the venting gas flow path and the inner space of the battery pack is blocked.

A battery shell, in particular, a battery shell for a traction battery of a motor vehicle, comprises a semi-permeable membrane that is integrally bonded or frictionally connected to the battery shell.

A cell assembly includes a first sleeve. The first sleeve includes a first side, a second side facing the first side, and a third side connecting the first side and the second side. The sleeve also includes a first open end between the first side and the second side, a second open end between the first side and the second side, and opposite the first open end, and a third open end between the first open end and the second open end and opposite the third side. The cell assembly includes a first pouch-type cell between the first side and the second side of the first sleeve. A first surface of the first pouch-type cell is adjacent to the third open end. A second surface of the first pouch-type cell is opposite the first surface, and spaced apart from the third side of the first sleeve by a predetermined distance.

A cell assembly includes a first sleeve. The first sleeve includes a first side, a second side facing the first side, and a third side connecting the first side and the second side. The sleeve also includes a first open end between the first side and the second side, a second open end between the first side and the second side, and opposite the first open end, and a third open end between the first open end and the second open end and opposite the third side. The cell assembly includes a first pouch-type cell between the first side and the second side of the first sleeve. A first surface of the first pouch-type cell is adjacent to the third open end. A second surface of the first pouch-type cell is opposite the first surface, and spaced apart from the third side of the first sleeve by a predetermined distance.

A vent plug (18) includes a head portion (35), a cylindrical portion (36) extending from the head portion (35), and a filter (34) provided inside the cylindrical portion (36). The cylindrical portion (36) has a through hole (43) that allows an inside and an outside of the cylindrical portion (36) to communicate with each other. The through hole (43) has an opening portion on an inner peripheral surface of the cylindrical portion (36). The filter (34) is provided so as to close the opening portion of the through hole (43).

A vent plug (18) includes a head portion (35), a cylindrical portion (36) extending from the head portion (35), and a filter (34) provided inside the cylindrical portion (36). The cylindrical portion (36) has a through hole (43) that allows an inside and an outside of the cylindrical portion (36) to communicate with each other. The through hole (43) has an opening portion on an inner peripheral surface of the cylindrical portion (36). The filter (34) is provided so as to close the opening portion of the through hole (43).

The present invention relates to a pressure relief element (11) to be used as an overpressure safety means in devices where a gaseous medium must be rapidly released in case of overpressure, wherein the pressure relief element (11) has at least one notch (9) which is designed as a predetermined breaking point where the pressure relief element (11) breaks at a certain level of overpressure, thereby irreversibly opening an exhaust path for the gaseous medium. The present invention also relates to a pressure relief device of an electrochemical battery, comprising such a pressure relief element and a battery comprising such a pressure relief device.