A battery housing includes a valve device for pressure equalization and for letting out a hot gas of a battery cell. The valve device has a valve seat in the form of a gas release opening in a housing wall of the battery housing and a valve body. The valve body closes the gas release opening when in a closed position, can be moved by a pressure-difference-induced internal pressure increase into a first open position in which the valve body reversibly opens the gas release opening to provide pressure equalization, and can be moved by a hot-gas-induced internal pressure increase into a second open position in which the valve body irreversibly opens the gas release opening to let out the hot gas.

A battery housing includes a valve device for pressure equalization and for letting out a hot gas of a battery cell. The valve device has a valve seat in the form of a gas release opening in a housing wall of the battery housing and a valve body. The valve body closes the gas release opening when in a closed position, can be moved by a pressure-difference-induced internal pressure increase into a first open position in which the valve body reversibly opens the gas release opening to provide pressure equalization, and can be moved by a hot-gas-induced internal pressure increase into a second open position in which the valve body irreversibly opens the gas release opening to let out the hot gas.

The present invention concerns a fire safety arrangement for a battery. More particularly, but not exclusively, this invention concerns a fire safety arrangement for a metal ion battery, for example a lithium ion battery cell. The metal ion battery cell comprises a plurality of electrodes and an electrolyte encased within a housing. The housing comprises a safety valve or vent to allow gas build up within the housing to vent outside the housing, and a fabric envelope surrounding the housing. Any sparks generated by the battery are contained within the fabric envelope, thereby reducing or eliminating the chances of fire or explosion.

A valve for a battery is provided to expel the air in case of overpressure generated in a battery includes from an external body (2) and a plunger (3) that travels inside it pushed by the battery pressure. The valve presents two opening positions and is coupled to a plunger (3), at least: —a first O-ring (5) that closes the passage of the air when there is no pressure and opens it when the plunger (3) moves at a first position from a given degree of pressure, —a second O-ring (6) that prevents the direct exit outside of the air when there is only a first degree of pressure and allows it when the degree of pressure is exceeded that opens the plunger (3) at second position, and —a ventilation element (4) that allows the passage of the air through it, but not the passage of the water.

A valve for a battery is provided to expel the air in case of overpressure generated in a battery includes from an external body (2) and a plunger (3) that travels inside it pushed by the battery pressure. The valve presents two opening positions and is coupled to a plunger (3), at least: —a first O-ring (5) that closes the passage of the air when there is no pressure and opens it when the plunger (3) moves at a first position from a given degree of pressure, —a second O-ring (6) that prevents the direct exit outside of the air when there is only a first degree of pressure and allows it when the degree of pressure is exceeded that opens the plunger (3) at second position, and —a ventilation element (4) that allows the passage of the air through it, but not the passage of the water.

In order to provide a pressure equalization apparatus (10) by means of which a pressure equalization can be brought about in the event of an overpressure—in particular, in an electrochemical system—and which is as simple as possible to produce, according to the invention, the pressure equalization apparatus comprises a main element (110), a sealing device (112), and a connection device (114) for connecting the main element and the sealing device, wherein the sealing device sealingly bears against the main element when the pressure equalization apparatus is in a closed state and is fixed relative to the main element by means of the connection device, and wherein a fixing connection between the main element and the sealing device which is formed thereby can be released in order to unblock a fluid connection between the interior of the pressure equalization apparatus and surroundings of the pressure equalization apparatus, and wherein the connection device comprises a spring element (150), the spring force of which acts in particular in a direction extending crosswise to an opening direction of the pressure equalization apparatus.

In order to provide a pressure equalization apparatus (10) by means of which a pressure equalization can be brought about in the event of an overpressure—in particular, in an electrochemical system—and which is as simple as possible to produce, according to the invention, the pressure equalization apparatus comprises a main element (110), a sealing device (112), and a connection device (114) for connecting the main element and the sealing device, wherein the sealing device sealingly bears against the main element when the pressure equalization apparatus is in a closed state and is fixed relative to the main element by means of the connection device, and wherein a fixing connection between the main element and the sealing device which is formed thereby can be released in order to unblock a fluid connection between the interior of the pressure equalization apparatus and surroundings of the pressure equalization apparatus, and wherein the connection device comprises a spring element (150), the spring force of which acts in particular in a direction extending crosswise to an opening direction of the pressure equalization apparatus.

A pressure relief valve includes a valve body; a valve cover matched with the valve body; a flexible element positioned between the valve body and the valve cover and having a through hole; and a breathable film covering the through hole. The flexible element has a compression portion at least partially surrounding the through hole and configured to be deformable to make the flexible element displace relative to the valve body. A battery pack can use the pressure relief valve. Due to the use of the pressure relief valve, internal pressure of the battery pack can be controlled.

According to embodiments, a pressure relief mechanism comprises a case with an installation hole formed therein, and a pressure relief valve. The pressure relief valve comprises an insertion portion which comprising a vent path formed in an axial portion of the insertion portion and a slit formed in a peripheral wall portion of the insertion portion so as to communicate with the vent path, a pedestal portion provided at an outer end of the insertion portion, a locking portion provided at an inner end of the insertion portion and locked on an inner edge of the installation hole, and a ring-like seal member interposed between around the installation hole and the pedestal portion, the seal portion comprising an elastic member.

According to embodiments, a pressure relief mechanism comprises a case with an installation hole formed therein, and a pressure relief valve. The pressure relief valve comprises an insertion portion which comprising a vent path formed in an axial portion of the insertion portion and a slit formed in a peripheral wall portion of the insertion portion so as to communicate with the vent path, a pedestal portion provided at an outer end of the insertion portion, a locking portion provided at an inner end of the insertion portion and locked on an inner edge of the installation hole, and a ring-like seal member interposed between around the installation hole and the pedestal portion, the seal portion comprising an elastic member.