Battery, battery pack and energy storage system

Abstract

The utility model provides a battery, a battery pack and an energy storage system, and belongs to the technical field of batteries. The battery comprises a cover plate, a shell and a battery cell, wherein the cover plate covers the shell; the cover plate is provided with a valve hole, the valve hole is provided with an anti-explosion valve plate, the surface, deviating from the battery cell, of the cover plate is provided with a bulge, the bulge is annularly arranged on the periphery of the valve hole to form a cavity, the cavity is provided with an opening, the opening is communicated with the valve hole, the opening is provided with a valve cover, the valve cover seals the opening, and the valve cover is connected with an elastic piece. When the internal pressure of the shell is larger than or equal to a first threshold value, the anti-explosion valve plate is broken, and the valve deck moves in the direction away from the opening and enables the elastic piece to deform. And when the internal pressure of the shell is smaller than or equal to a second threshold value, the elastic piece is used for enabling the valve cover to move in the direction close to the opening and sealing the opening. And the bulge, the valve cover and the elastic piece are matched to form an anti-explosion valve piece, so that the anti-explosion valve piece can be automatically closed in time after the valve is opened, and the safety of the battery after thermal runaway is ensured. And the explosion-proof valve plate ensures that the battery is in a reliable sealing state during non-thermal runaway.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to batteries, battery packs and energy storage systems. Background Art

[0002] Secondary batteries such as lithium-ion batteries and sodium-ion batteries generally include: battery cells, a housing and a cover plate. The cover plate is welded to the housing to form a sealed cavity, and the battery cells are accommodated in the sealed cavity. The cover plate is provided with a positive electrode post, a negative electrode post and an explosion-proof valve. The explosion-proof valve can be opened when the battery cells undergo thermal runaway, so as to release the battery cell ejecta such as high-temperature flue gas, electrolyte, solid particles, etc.

[0003] In the related art, the explosion-proof valve includes an explosion-proof valve sheet. The explosion-proof valve sheet is connected to the cover plate and seals the valve hole provided on the cover plate. When the battery cells undergo thermal runaway, the explosion-proof valve sheet breaks under the impact of the battery cell ejecta, realizing the opening of the explosion-proof valve.

[0004] However, the explosion-proof valve always remains open after being opened, which makes it easy for external air or impurities to enter the battery cells therefrom, and even causes the battery cells to catch fire, posing a great safety hazard. Summary of the Utility Model

[0005] Embodiments of the utility model provide a battery, a battery pack and an energy storage system, which can solve the technical problems existing in the related art. Specifically, the technical solutions are as follows.

[0006] On the one hand, a battery is provided. The battery includes a cover plate, battery cells and a housing for accommodating the battery cells. The cover plate covers the housing. The cover plate is provided with a valve hole, and an explosion-proof valve sheet is installed in the valve hole. A protrusion is provided on the surface of the cover plate facing away from the battery cells. The protrusion surrounds the periphery of the valve hole to form a cavity. The cavity is provided with an opening, and the opening is communicated with the valve hole. A valve cover is provided at the opening, and the valve cover seals the opening. The valve cover is connected with an elastic member. When the internal pressure of the housing is greater than or equal to a first threshold value, the explosion-proof valve sheet breaks, and the valve cover moves away from the opening, causing the elastic member to deform. When the internal pressure of the housing is less than or equal to a second threshold value, the elastic member is used to move the valve cover towards the opening and seal the opening.

[0007] The battery provided by the embodiment of the present utility model, on the one hand, by providing an explosion-proof valve piece on the cover plate, the explosion-proof valve piece is used to close the valve hole to seal the cavity where the battery cell is located. The explosion-proof valve piece is a single component and is fixedly connected to the cover plate, which makes the explosion-proof valve piece have stable sealing reliability. For the case where no abnormality occurs from the fresh state to the end of the life cycle of the battery cell, the presence of the explosion-proof valve piece can ensure that the battery is always in a reliable sealed state during its life cycle and avoid abnormal valve opening of the battery. On the other hand, the protrusion, the valve cover and the elastic member cooperate to form an explosion-proof valve member. Thus, the explosion-proof valve piece and the explosion-proof valve member are arranged in sequence from the inside to the outside. When the battery cell undergoes thermal runaway, so that the internal pressure of the housing is greater than or equal to the first threshold value, the explosion-proof valve piece ruptures, the valve cover moves away from the opening and causes the elastic member to deform. At this time, the ejected matter of the battery cell is ejected through the explosion-proof valve piece and the explosion-proof valve member in sequence. As the ejected matter of the battery cell leaks out, when the internal pressure of the housing is less than or equal to the second threshold value, it is not enough to overcome the elastic member to deform it, and the elastic member elastically resets to make the valve cover move towards the direction close to the opening and seal the opening. Thus, the explosion-proof valve member returns to the sealed state, avoiding external air or impurities from entering the battery internal, reducing the risk of valve opening and combustion of the battery cell, and improving the safety after thermal runaway of the battery cell.

[0008] In some possible implementation manners, the elastic member has a pre-tightening force, and the pre-tightening force of the elastic member is greater than the external atmospheric pressure and less than or equal to the first threshold value. By making the pre-tightening force of the elastic member greater than the external atmospheric pressure, the internal pressure of the housing in the sealed state is greater than the external atmospheric pressure, ensuring that the air outside the battery cannot enter the battery cell through the valve cover. By making the pre-tightening force of the elastic member less than or equal to the first threshold value, it is ensured that after the explosion-proof valve piece opens the valve, the explosion-proof valve member also opens the valve in time.

[0009] In some possible implementation manners, the valve cover moves in a translational manner, which includes: the valve cover abuts against the protrusion through the elastic member, and the force application direction of the elastic member on the valve cover is perpendicular to the valve cover, so that the valve cover moves translationally along the axial direction of the protrusion to open or close the opening.

[0010] As an example, the protrusion has an upper open end and a lower open end, the lower open end is connected to the cover plate and communicates with the valve hole, and the upper open end provides the opening; the valve cover abuts against the upper open end of the protrusion and covers the opening, the elastic member is located inside the protrusion, and both ends of the elastic member are respectively connected to the valve cover and the protrusion. This solution has the advantages of simple structure, few components, and reliable operation.

[0011] As another example, the protrusion has an upper open end and a lower open end. The lower open end is connected to the cover plate and communicates with the valve hole, and the lower open end provides the opening; the valve cover abuts against the lower open end of the protrusion and covers the opening. The elastic member is located inside the protrusion, and two ends of the elastic member are respectively connected to the valve cover and the protrusion. This solution can also achieve the translational movement of the valve cover.

[0012] In some other possible implementation manners, the valve cover moves in a rotational manner, which includes: the valve cover is connected to the protrusion through a hinge mechanism, such that the valve cover rotates about the hinge mechanism as a rotation axis, and the rotation axis of the valve cover is skew perpendicular to the axis of the protrusion to open or close the opening.

[0013] As an example, the protrusion has an upper open end and a lower open end. The lower open end is connected to the cover plate and communicates with the valve hole, and the upper open end provides the opening; the valve cover is hinged to the upper open end of the protrusion through a hinge mechanism and covers the opening. The elastic member is located inside the protrusion, and two ends of the elastic member are respectively connected to the valve cover and the protrusion.

[0014] As another example, the protrusion has an upper open end and a lower open end. The lower open end is connected to the cover plate and communicates with the valve hole, and the upper open end provides the opening; the valve cover includes a support shaft connected to the opening. The support shaft divides the opening into a first sub-opening and a second sub-opening. The valve cover further includes a first sub-valve cover covering the first sub-opening and a second sub-valve cover covering the second sub-opening. The first sub-valve cover and the second sub-valve cover are respectively hinged to two sides of the support shaft through a hinge mechanism; the elastic member is a torsion spring, the body of the torsion spring is sleeved on the support shaft, one torsion arm of the torsion spring abuts against the first sub-valve cover, and the other torsion arm of the torsion spring abuts against the second sub-valve cover.

[0015] In some possible implementation manners, the cover plate further includes: a sealing ring, and the sealing ring is arranged between the protrusion and the valve cover. By arranging the sealing ring between the protrusion and the valve cover, the gap between the valve cover and the protrusion can be effectively sealed, ensuring the reliable sealing of the valve cover to the protrusion and improving the sealing effect of the explosion-proof valve component.

[0016] In some possible implementation manners, a limiting groove is provided on a surface of the cover plate facing away from the battery cell. The lower end portion of the protrusion is embedded in the limiting groove, such that the protrusion and the cover plate are mutually limited in a direction parallel to the cover plate, improving the assembly stability of the explosion-proof valve component on the cover plate.

[0017] In some possible implementation manners, the cover plate includes a metal cover plate and an insulating partition connected to one side of the metal cover plate facing the battery cell. The explosion-proof valve sheet is welded to the metal cover plate, and the protrusion is welded to the metal cover plate. Thus, the explosion-proof valve sheet and the explosion-proof valve component form an integrated cover plate structure with a valve together with the metal cover plate, which not only helps to improve the structural stability of the cover plate, but also helps to improve the sealing performance of the explosion-proof valve component and reduce the failure probability such as air leakage.

[0018] On the other hand, a battery pack is provided, which includes a plurality of batteries as described above, and the plurality of batteries are connected in series or in parallel.

[0019] In some possible implementation manners, the battery pack has a smoke exhaust channel, and the protrusion extends into the smoke exhaust channel, so that the valve cover and the opening of the protrusion are located inside the smoke exhaust channel.

[0020] On yet another aspect, an energy storage system is provided, which includes a power converter and at least one battery pack as described above; the power converter is configured to perform power conversion on the voltage output by the battery pack and output it to the power grid or a load, and / or perform power conversion on the voltage output by an external power source and output it to the battery pack. Description of the Drawings

[0021] Figure 1 A cross-sectional view of the first exemplary battery provided by an embodiment of the present invention;

[0022] Figure 2 For Figure 1 A combined view of the cover plates in the battery shown;

[0023] Figure 3 For Figure 1 An exploded view of the cover plates in the battery shown;

[0024] Figure 4 A cross-sectional view of the second exemplary battery provided by an embodiment of the present invention;

[0025] Figure 5 A cross-sectional view of the third exemplary battery provided by an embodiment of the present invention;

[0026] Figure 6 A cross-sectional view of the fourth exemplary battery provided by an embodiment of the present invention;

[0027] Figure 7 A cross-sectional view of the fifth exemplary battery provided by an embodiment of the present invention;

[0028] Figure 8 For Figure 7 A cross-sectional view of the battery shown in the valve-opening state;

[0029] Figure 9 Cross-sectional view of the sixth exemplary battery provided by the embodiment of the present utility model;

[0030] Figure 10 is Figure 9 Top view of the valve cover in the battery shown;

[0031] Figure 11 is Figure 9 Cross-sectional view of the battery shown in the valve-opening state;

[0032] Figure 12 Structural schematic diagram of an exemplary explosion-proof valve sheet provided by the embodiment of the present utility model;

[0033] Figure 13 Cross-sectional view of an exemplary battery pack provided by the embodiment of the present utility model.

[0034] Reference numerals respectively represent:

[0035] 001, battery;

[0036] 100, cover plate;

[0037] 11, plate body; 110, valve hole; 111, limiting groove; 101, metal cover plate; 102, insulating partition;

[0038] 12, explosion-proof valve sheet; 120, notch;

[0039] 13, explosion-proof valve member; 131, protrusion; 1310, opening; 1311, upper opening end; 1312, lower opening end;

[0040] 132, valve cover; 1321, first sub-valve cover; 1322, second sub-valve cover; 1323, support shaft;

[0041] 133, elastic member;

[0042] 14, hinge mechanism;

[0043] 15, sealing ring;

[0044] 16, negative electrode post; 17, positive electrode post;

[0045] 200, housing;

[0046] 300, battery cell;

[0047] 002, smoke exhaust channel. Detailed implementation manners

[0048] In the description of the embodiments of the present utility model, it should be understood that the orientation or positional relationships indicated by terms such as "upper", "lower", "inner", "outer", "top", "bottom", "vertical", "horizontal", "height", "depth", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. When the product is placed in different postures, the orientation may change. Therefore, it should not be construed as a limitation on the embodiments of the present utility model. For example, for the battery involved in the embodiments of the present utility model, the orientation where the cover plate is located is "upper", and correspondingly, the orientation where the housing is located is "lower".

[0049] For secondary batteries such as lithium-ion batteries and sodium-ion batteries, they generally include: a battery cell, a housing, and a cover plate. The cover plate is welded to the housing to form a sealed cavity, and the battery cell is accommodated in the sealed cavity. When an exothermic side reaction occurs inside the battery cell, resulting in heat accumulation, it will not only cause combustion or explosion, but also generate toxic gases at the moment of ignition. Therefore, an explosion-proof valve is usually provided on the cover plate to timely relieve the pressure inside the battery and discharge the toxic gases.

[0050] In the related art, the explosion-proof valve includes an explosion-proof valve sheet, which is connected to the cover plate and seals the valve hole provided on the cover plate. When the battery cell undergoes thermal runaway, the explosion-proof valve sheet breaks under the impact of the ejected substances from the battery cell, realizing the opening of the explosion-proof valve, thereby releasing the ejected substances from the battery cell such as high-temperature flue gas, electrolyte, and solid particles.

[0051] It can be seen that during the use of the battery cell, once thermal runaway occurs, such as internal short circuit, foreign object piercing, external heat source triggering, etc., the explosion-proof valve opens. After the pressure inside the battery is relieved, the explosion-proof valve cannot close, that is, the explosion-proof valve remains open after opening. This makes it easy for external air or impurities to enter the battery cell through this, and may even cause the battery cell to catch fire and burn, and even cause a chain runaway reaction in adjacent battery cells, posing a great potential safety hazard.

[0052] In view of the above technical problems, the embodiments of the present utility model provide a battery, as shown in the attached Figure 1 which exemplifies a sectional view of a battery. As shown in the attached Figure 1 , the battery includes a cover plate 100, a battery cell 300, and a housing 200 for accommodating the battery cell 300. The cover plate 100 covers the housing 200.

[0053] The attached Figure 2 and the attached Figure 3 respectively exemplify the combined view and the exploded view of the cover plate 100 integrated with the explosion-proof valve module. On the basis of Figure 1 further combined with Figure 2 and Figure 3As shown in the figure, the cover plate 100 is provided with a valve hole 110, and an explosion-proof valve sheet 12 is installed in the valve hole 110. A protrusion 131 is provided on the surface of the cover plate 100 facing away from the battery cell 300. The protrusion 131 is arranged around the outer periphery of the valve hole 110 to form a cavity. The cavity is provided with an opening 1310, and the opening 1310 is communicated with the valve hole 110 (for example, Figure 2 It is exemplified that the opening 1310 and the valve hole 110 are arranged opposite to each other and communicated), and a valve cover 132 is arranged at the opening 1310. The valve cover 132 seals the opening 1310, and the valve cover 132 is connected with an elastic member 133.

[0054] When the pressure inside the housing 200 is greater than or equal to the first threshold value, the explosion-proof valve sheet 12 ruptures, and the valve cover 132 moves in a direction away from the opening 1310 and deforms the elastic member 133. When the pressure inside the housing 200 is less than or equal to the second threshold value, the elastic member 133 is used to move the valve cover 132 in a direction close to the opening 1310 and seal the opening 1310.

[0055] It should be noted that (1) the cover plate 100 involved in the embodiment of the present invention at least includes a plate body 11. Figure 1 And Figure 2 It is exemplified the composition of the plate body 11. As shown in Figure 2 , the plate body 11 generally includes a metal cover plate 101 and an insulating partition 102. The insulating partition 102 is connected to the surface of the metal cover plate 101 close to the battery cell 300. The insulating partition 102 is used to insulate and isolate the metal cover plate 101 and the battery cell 300. Among them, the valve hole 110 is simultaneously arranged on both the metal cover plate 101 and the insulating partition 102. (2) In the embodiment of the present invention, the components formed by the protrusion 131 (which can be regarded as a valve housing), the valve cover 132 and the elastic member 133 can be called an explosion-proof valve member 13. Thus, the explosion-proof valve sheet 12 and the explosion-proof valve member 13 are arranged in sequence from inside to outside to form an explosion-proof valve module with a dual explosion-proof function. The explosion-proof valve module can be integrally arranged on the plate body 11 of the cover plate 100. Therefore, the cover plate 100 is a new cover plate integrated with an explosion-proof valve module with a dual explosion-proof function. (3) The explosion-proof valve sheet 12 is installed at the valve hole 110 to close the valve hole 110. Thus, the inner cavity of the battery is isolated from the outside by using the explosion-proof valve sheet 12. The explosion-proof valve sheet 12 can be arranged at any position distributed along the axial direction of the valve hole 110. For example, Figure 2 It is exemplified that the explosion-proof valve sheet 12 is arranged at a position between the two ends of the valve hole 110.

[0056] The battery provided by the embodiment of the present utility model, on the one hand, by providing an explosion-proof valve sheet 12 on the cover plate 100, the explosion-proof valve sheet 12 is used to close the valve hole 110 to seal the cavity where the battery cell 300 is located. The explosion-proof valve sheet 12 is a single component and is fixedly connected to the plate body 11, which makes the explosion-proof valve sheet 12 have stable sealing reliability. For the situation where the battery cell 300 does not show any abnormality from the fresh state to the end of its life, the presence of the explosion-proof valve sheet 12 can ensure that the battery is always in a reliable sealed state during its life cycle, avoiding abnormal valve opening of the battery. On the other hand, the protrusion 131, the valve cover 132 and the elastic member 133 cooperate to form an explosion-proof valve member 13. Thus, the explosion-proof valve sheet 12 and the explosion-proof valve member 13 are arranged in sequence from the inside to the outside. When the battery cell 300 undergoes thermal runaway, so that the internal pressure of the housing 200 is greater than or equal to the first threshold value, the explosion-proof valve sheet 12 ruptures, and the valve cover 132 moves away from the opening 1310 and deforms the elastic member 133. At this time, the battery cell ejecta sprays out through the explosion-proof valve sheet 12 and the explosion-proof valve member 13 in sequence. As the battery cell ejecta leaks out, when the internal pressure of the housing 200 is less than or equal to the second threshold value, it is not sufficient to overcome the elastic member 133 to deform it, and the elastic member 133 elastically returns to its original position to make the valve cover 132 move towards the direction close to the opening 1310 and seal the opening 1310. Thus, the explosion-proof valve member 13 returns to the sealed state, avoiding external air or impurities from entering the battery interior, reducing the risk of battery cell valve opening and combustion, and enhancing the safety after the occurrence of battery cell thermal runaway.

[0057] In summary, for the battery provided by the embodiment of the present utility model, through the arrangement of the explosion-proof valve sheet 12 and the explosion-proof valve member 13, on the one hand, the explosion-proof valve member 13 is used to ensure timely automatic closing after valve opening, ensuring the safety of the battery after thermal runaway. On the other hand, based on the excellent sealing reliability of the explosion-proof valve sheet 12, for the situation where the battery cell 300 does not show any abnormality from the fresh state to the end of its life, it can ensure that the battery is always in a reliable sealed state during its life cycle, avoiding abnormal valve opening of the battery.

[0058] Regarding the explosion-proof valve sheet 12 involved in the embodiment of the present utility model, it can adopt the known explosion-proof valve sheet structure currently. For example, Figure 12 illustrates a structure of an explosion-proof valve sheet 12. As shown in Figure 12 , the explosion-proof valve sheet 12 is a metal valve sheet, and it has a notch 120 (also known as a blasting notch) thereon. When the explosion-proof valve sheet 12 is impacted by the battery cell ejecta, when the impact pressure borne by the explosion-proof valve sheet 12 is greater than the valve opening pressure of the explosion-proof valve sheet 12, the explosion-proof valve sheet 12 ruptures along the notch 120, thereby releasing the internal pressure and gas of the battery and other battery cell ejecta.

[0059] In the embodiments of the present utility model, the arrangement manner of the explosion-proof valve sheet 12 on the cover plate 100 includes but is not limited to the following situations: (1) The explosion-proof valve sheet 12 is connected to the metal cover plate 101 (see Figure 2 ). For example, the explosion-proof valve sheet 12 is made of metal and is connected to the metal cover plate 101 by welding. Further, the surface of the metal cover plate 101 facing the insulating partition 102 has a receiving groove, and the explosion-proof valve sheet 12 is embedded in the receiving groove (see Figure 2 ). Of course, it is not excluded that the explosion-proof valve sheet 12 can also be connected to the surface of the metal cover plate 101 facing away from the insulating partition 102, or the explosion-proof valve sheet 12 is connected to the inner side wall of the valve hole 110 on the metal cover plate 101. (2) The metal cover plate 101 is connected to the insulating partition 102, for example, by bonding (not shown in the figure).

[0060] For the explosion-proof valve member 13 involved in the above embodiments of the present utility model, Figure 3 it is exemplified that its protrusion 131 is connected to the side of the metal cover plate 101 of the cover plate 100 facing away from the insulating partition 102. And, its valve cover 132 is movably connected or abutted against the protrusion 131 and covers its opening 1310. Under the impact of the ejected material of the battery cell, the pre-tightening force of the elastic member 133 itself is overcome, and the valve cover 132 can move from the position covering the opening 1310 to the position opening the opening 1310. Thus, the explosion-proof valve member 13 realizes valve opening. Based on the elastic reset function of the elastic member 133, the valve cover 132 can reset and move from the position opening the opening 1310 to the position covering the opening 1310. Thus, the explosion-proof valve member 13 realizes valve closing.

[0061] It can be seen that the elastic member 133 determines that the explosion-proof valve member 13 can realize automatic valve closing. The pre-tightening force of the elastic member 133 itself refers to the initial tension that the elastic member 133 has when not subjected to external force, which can ensure that the elastic member 133 has a certain elastic deformation and resilience ability during the working process. In some examples, the elastic member 133 is also used to make the valve cover 132 in close contact with the protrusion 131 based on its pre-tightening force, improving the sealing effect of the valve cover 132 on the opening 1310 of the protrusion 131.

[0062] In the embodiment of the present utility model, the first threshold mentioned above can be considered as the opening pressure of the explosion-proof valve plate 12, and the pre-tightening force of the elastic member 133 is less than or equal to the first threshold. Thus, when the explosion-proof valve plate 12 opens, the pressure released inside the housing 200 can not only impact the valve cover 132 to make it move, but also overcome the pre-tightening force of the elastic member 133, causing the elastic member 133 to deform. The pre-tightening force of the elastic member 133 is greater than the second threshold mentioned above. Thus, when the internal pressure of the housing 200 is less than or equal to the second threshold, the internal pressure of the housing 200 will not be able to overcome the pre-tightening force of the elastic member 133 to make it deform. Therefore, the elastic member 133 elastically returns to its initial pre-tightened state from the deformed state. The pre-tightening force of the elastic member 133 can be adjusted so that the elastic member 133 can respond in a timely manner to the internal pressure of the housing 200, and thus change its state in a timely manner.

[0063] In some examples, the opening pressure of the explosion-proof valve member 13 is set to meet the following conditions: the opening pressure of the explosion-proof valve member 13 is equal to the pre-tightening force of the elastic member 133, and the pre-tightening force of the elastic member 133 is greater than the external atmospheric pressure and less than or equal to the first threshold (i.e., the opening pressure of the explosion-proof valve plate 12).

[0064] By making the opening pressure of the explosion-proof valve member 13 equal to the pre-tightening force of the elastic member 133, when the internal pressure of the housing 200 (i.e., the impact force of the cell ejecta) is greater than the pre-tightening force of the elastic member 133, the elastic member 133 can produce elastic deformation, thereby allowing the valve cover 132 to move from the position covering the opening 1310 to the position opening the opening 1310. When the internal pressure of the housing 200 is less than the pre-tightening force of the elastic member 133, the elastic member 133 elastically returns, thereby driving the valve cover 132 to move back from the position opening the opening 1310 to the position covering the opening 1310.

[0065] As the cell ejecta leaks out, the internal pressure of the housing 200 decreases. When the internal pressure of the housing 200 is less than the pre-tightening force of the elastic member 133, that is, less than the opening pressure of the explosion-proof valve member 13, the valve cover 132 covers the protrusion 131 to seal it. Since the opening pressure of the explosion-proof valve member 13 is greater than the external atmospheric pressure, the internal pressure of the sealed housing 200 is greater than the external atmospheric pressure, ensuring that the air outside the battery cannot enter the cell 300 through the valve cover 132. (Based on this, the explosion-proof valve member 13 can be considered as a positive pressure explosion-proof valve member).

[0066] By making the opening pressure of the explosion-proof valve member 13 less than or equal to the opening pressure of the explosion-proof valve plate 12, it is ensured that after the explosion-proof valve plate 12 opens, the explosion-proof valve member 13 also opens in a timely manner. In addition, for the case where the pressure of the cell ejecta decreases after breaking through the explosion-proof valve plate 12, by making the opening pressure of the explosion-proof valve member 13 less than the opening pressure of the explosion-proof valve plate 12, it can also be ensured that when the cell ejecta breaks through the explosion-proof valve plate 12 and further impacts the valve cover 132, the elastic member 133 can be elastically deformed to allow the valve cover 132 to open.

[0067] In some examples, the first threshold, that is, the opening pressure of the explosion-proof valve plate 12, can be 0.6 MPa to 1.0 MPa, which includes but is not limited to: 0.6 MPa, 0.7 MPa, 0.8 MPa, 0.9 MPa, 1 MPa, etc. When no abnormal phenomena such as thermal runaway occur during the period from the fresh state to the end of life of the cell 300, the internal pressure of the battery is stable below 0.6 MPa. Thus, the explosion-proof valve plate 12 plays a stable sealing role during this period. When the cell 300 undergoes thermal runaway, the internal pressure of the housing 200 will be greater than the opening pressure of the explosion-proof valve plate 12. Thus, the explosion-proof valve plate 12 opens for exhaust.

[0068] In some examples, the opening pressure of the explosion-proof valve member 13 can be 0.2 MPa to 0.4 MPa (i.e., the second threshold is less than 0.2 MPa to 0.4 MPa), for example, this includes but is not limited to 0.2 MPa, 0.25 MPa, 0.3 MPa, 0.35 MPa, 0.4 MPa, etc., so as to ensure that the internal pressure of the housing 200 is greater than the external air pressure, and external air cannot enter the battery through the valve cover 132.

[0069] In summary, for the battery provided by the embodiment of the present invention, through the combined action of the explosion-proof valve plate 12 with higher sealing reliability and the positive pressure explosion-proof valve member 13 with automatic opening and closing, it can not only provide reliable sealing protection for the cell 300 during the life cycle when the cell 300 does not have abnormalities, but also open the valve in a timely manner to relieve pressure when the cell 300 undergoes thermal runaway, and automatically close the valve in a timely manner at a certain moment when the internal pressure of the battery decreases to be greater than the external atmospheric pressure, re-seal the battery, and prevent external air from entering the battery, thereby improving the safety of the battery. Due to the presence of the elastic member 133, the explosion-proof valve member 13 can automatically open and close in real time according to the internal pressure of the battery, and both the number of times of opening and closing can be multiple times.

[0070] For the explosion-proof valve member 13, its valve cover 132 is arranged in a movable manner, and the elastic member 133 acts on the valve cover 132 to reset it. All explosion-proof valve members 13 that satisfy this function are applicable to the embodiment of the present invention. The following is an exemplary description of the arrangement of the valve cover 132 and the elastic member 133 in the explosion-proof valve member 13.

[0071] In some embodiments (1), the valve cover 132 moves in a translational manner and is attached Figure 4 - attached Figure 6 Embodiments of the explosion-proof valve member 13 of the valve cover 132 based on translation are respectively exemplified. As attached Figure 4 - attached Figure 6 shown, the valve cover 132 is abutted against the protrusion 131 through the elastic member 133, and the force applied by the elastic member 133 to the valve cover 132 is perpendicular to the valve cover 132, so that the valve cover 132 moves translationally along the axial direction of the protrusion 131 to open or close the opening 1310.

[0072] Among them, by making the force applied by the elastic member 133 to the valve cover 132 perpendicular to the valve cover 132, the translational direction of the valve cover 132 is along the axial direction of the protrusion 131, that is, the translational direction of the valve cover 132 is perpendicular to the plane where the valve cover 132 is located, that is Figure 4 and Figure 5 the up and down directions in

[0073] For embodiment (1), taking Figure 4 as an example, the valve cover 132 is closely attached to the protrusion 131 under the pre-tightening force of the elastic member 133, so as to achieve a tight seal of the opening 1310 of the protrusion 131. The valve cover 132 can move translationally along the direction away from the protrusion 131 under the impact of the cell ejecta (for example, Figure 4 the upward arrow in

[0074] Figure 4 exemplifies some embodiments (1.1) based on embodiment (1). In this embodiment (1.1), the structure of the protrusion 131 can still refer to the protrusion 131 shown in Figure 3 The protrusion 131 has an upper opening end 1311 and a lower opening end 1312. The lower opening end 1312 is connected to the cover plate 100 (i.e., the plate body 11) and is in communication with the valve hole 110. The upper opening end 1311 provides the opening 1310. Further as attached Figure 4 shown, the valve cover 132 abuts against the upper opening end 1311 of the protrusion 131 and covers the opening 1310. The elastic member 133 is located inside the protrusion 131, and both ends of the elastic member 133 are respectively connected to the valve cover 132 and the protrusion 131. Embodiment (1.1) has the advantages of simple structure, few components, and reliable operation.

[0075] In the embodiment of the present utility model, the "upper opening end 1311" of the protrusion 131 refers to the end of the protrusion 131 that is away from the plate body 11, and the "lower opening end 1312" of the protrusion 131 refers to the end of the protrusion 131 that is connected to the plate body 11. The "upper opening end 1311" and the "lower opening end 1312" of the protrusion 131 are arranged oppositely and communicated with each other.

[0076] The protrusion 131 may be, for example, a cylindrical structure with openings at both ends, and it at least includes a closed cylindrical side wall. The cylindrical side wall encloses to form the inner cavity of the protrusion 131. The cross-sectional shape of the protrusion 131 includes, but is not limited to, circular, elliptical, square, rectangular, etc.

[0077] For the implementation scheme (1.1), the upper opening end 1311 of the protrusion 131 provides an opening 1310. The valve cover 132 abuts against the upper opening end 1311 of the protrusion 131 and covers the opening 1310. On this basis, the upper end of the elastic member 133 is connected to the valve cover 132, and the lower end of the elastic member 133 is connected to the protrusion 131. For example, the lower opening end 1312 of the protrusion 131 has an annular bottom wall, and the lower end of the elastic member 133 is connected to the annular bottom wall of the protrusion 131.

[0078] Exemplarily, the elastic member 133 may be a tension spring. Based on the pre-tightening force of the tension spring itself, the valve cover 132 can closely adhere to the upper opening end 1311 of the protrusion 131. That is to say, when the tension spring is in a natural state, the valve cover 132 closely adheres to the protrusion 131 to achieve reliable sealing of the opening 1310.

[0079] The working principle of the implementation scheme (1.1) is as follows:

[0080] When the battery cell 300 undergoes thermal runaway, the ejecta of the battery cell breaks through the explosion-proof valve sheet 12 and enters the protrusion 131 through the valve hole 110, and then impacts the valve cover 132, causing the valve cover 132 to move in a direction away from the protrusion 131 to open the opening 1310. At the same time, the elastic member 133 undergoes tensile deformation. As the ejecta of the battery cell gradually discharges outward, when the pressure inside the housing 200 drops to be less than the opening pressure of the explosion-proof valve member 13, the elastic member 133 undergoes elastic reset and drives the valve cover 132 to reset. The valve cover 132 closely adheres to the protrusion 131 again to achieve reliable sealing of the opening 1310. Thus, external air cannot enter the battery through the explosion-proof valve member 13.

[0081] For the implementation scheme (1.1), the number of the elastic members 133 may be one. As shown in the appendix Figure 4 When the number of the elastic members 133 is one, the axial direction (i.e., the elastic telescopic direction) of the elastic member 133 is perpendicular to the valve cover 132. The elastic member 133 is along Figure 4It is arranged in the vertical direction as shown, so that the valve cover 132 moves horizontally in the up and down direction to move away from or close to the upper opening end 1311 of the protrusion 131.

[0082] Furthermore, for the single elastic member 133 in the form of a tension spring, along its axial direction, the diameter of the elastic member 133 remains unchanged, that is, the elastic member 133 can be a spring with a constant diameter. Of course, it is not excluded that along the axial direction of the elastic member 133, the diameter of the elastic member 133 gradually changes. For example, the elastic member 133 is a conical spring.

[0083] For the embodiment (1.1), the number of the elastic members 133 can be multiple, and the multiple elastic members 133 are evenly spaced along the circumferential direction of the protrusion 131 ( Figure 5 It is exemplified that the number of the elastic members 133 is two). There is an included angle between the axial direction of each elastic member 133 and the vertical direction, and each elastic member 133 is arranged obliquely with respect to the vertical direction. Since the multiple elastic members 133 are evenly distributed, the elastic expansion and contraction direction (i.e., the force application direction) of the elastic mechanism formed by the multiple elastic members 133 is along the vertical direction and perpendicular to the valve cover 132. Therefore, the valve cover 132 moves horizontally in the up and down direction to move away from or close to the upper opening end 1311 of the protrusion 131. Furthermore, for the case where the elastic members 133 are arranged in multiple numbers, the elastic members 133 can be tension springs with a constant diameter or tension springs with a variable diameter.

[0084] Figure 6 Some embodiments (1.2) based on the embodiment (1) are exemplified. The structure of the protrusion 131 in this embodiment (1.2) can still refer to Figure 3 the protrusion 131 shown in. The protrusion 131 has an upper opening end 1311 and a lower opening end 1312. The lower opening end 1312 is connected to the plate body 11 and communicates with the valve hole 110, and the lower opening end 1312 provides an opening 1310; further as shown in Figure 6 the figure, the valve cover 132 abuts against the lower opening end 1312 of the protrusion 131 and covers the opening 1310. The elastic member 133 is located inside the protrusion 131, and both ends of the elastic member 133 are respectively connected to the valve cover 132 and the protrusion 131.

[0085] For Embodiment (1.2), the lower opening end 1312 of the protrusion 131 provides an opening 1310. The valve cover 132 abuts against the lower opening end 1312 of the protrusion 131 and covers the opening 1310. On this basis, the lower end of the elastic member 133 is connected to the valve cover 132, and the upper end of the elastic member 133 is connected to the protrusion 131. For example, the upper opening end 1311 of the protrusion 131 has an annular top wall, and the upper end of the elastic member 133 is connected to this annular top wall of the protrusion 131. Exemplarily, the elastic member 133 can be a compression spring. Based on the pre-tightening force of the compression spring itself, the valve cover 132 can closely adhere to the lower opening end 1312 of the protrusion 131. That is to say, when the compression spring is in its natural state, the valve cover 132 closely adheres to the protrusion 131 to achieve reliable sealing of the opening 1310.

[0086] The working principle of Embodiment (1.2) is as follows:

[0087] When thermal runaway occurs in the battery cell 300, the ejecta of the battery cell breaks through the explosion-proof valve piece 12 and then impacts the valve cover 132, causing the valve cover 132 to move away from the lower opening end 1312 of the protrusion 131 to open the opening 1310. At the same time, the elastic member 133 undergoes compressive deformation. As the ejecta of the battery cell gradually discharges outward, when the pressure inside the housing 200 drops below the opening pressure of the explosion-proof valve member 13, the elastic member 133 undergoes elastic reset and drives the valve cover 132 to reset. The valve cover 132 closely adheres to the protrusion 131 again to achieve reliable sealing of the opening 1310. Thus, external air cannot enter the battery interior through the explosion-proof valve member 13.

[0088] For Embodiment (1.2), the number of elastic members 133 can be one. As shown in the appendix Figure 6 When the number of elastic members 133 is one, the axial direction of the elastic member 133 is perpendicular to the valve cover 132, and the elastic member 133 is arranged along the Figure 1 vertical direction shown. Thus, the valve cover 132 translates in the up and down direction to move away from or close to the lower opening end 1312 of the protrusion 131.

[0089] Furthermore, for the single elastic member 133 in the form of a compression spring, along its axial direction, the diameter of the elastic member 133 remains unchanged, that is, the elastic member 133 can be a constant-diameter spring. Of course, it is not excluded that along the axial direction of the elastic member 133, the diameter of the elastic member 133 gradually changes. For example, the elastic member 133 is a conical spring, and along the direction from bottom to top, the diameter of the elastic member 133 gradually increases. Thus, when the elastic member 133 is compressed, each coil shrinks into the plane of the larger coil, which is beneficial to reducing the volume of the explosion-proof valve member 13.

[0090] For Embodiment (1.2), the number of elastic members 133 can also be multiple (this can also be referred to Figure 5(Arrangement of the middle elastic member 133), a plurality of elastic members 133 are evenly spaced along the circumferential direction of the protrusion 131. There is an angle between the axial direction of each elastic member 133 and the vertical direction, and each elastic member 133 is arranged obliquely with respect to the vertical direction. Since the plurality of elastic members 133 are evenly distributed, the elastic expansion and contraction direction of the elastic mechanism formed by the plurality of elastic members 133 is along the vertical direction and perpendicular to the valve cover 132. Thus, the valve cover 132 moves translationally in the up and down direction to move away from or close to the lower opening end 1312 of the protrusion 131. Further, for the case where the elastic members 133 are arranged in plurality, the elastic members 133 can be equal-diameter compression springs or variable-diameter compression springs.

[0091] In the above embodiment (1), an exemplary description is made of the solution in which the movement mode of the valve cover 132 is translational. In some embodiments (2), the valve cover 132 moves in a rotational manner. Figure 7 - Figure 11 All exemplify embodiments of the explosion-proof valve member 13 of the valve cover 132 based on rotation. Figure 7 For example, the valve cover 132 is connected to the protrusion 131 through a hinge mechanism 14, so that the valve cover 132 rotates about the hinge mechanism 14 as the rotation axis, and the rotation axis of the valve cover 132 is skew perpendicular to the axis of the protrusion 131 to open or close the opening 1310.

[0092] For embodiment (2), the valve cover 132 is connected to the protrusion 131 through a hinge mechanism 14. For example, one side of the valve cover 132 is connected to the corresponding position of the end of the protrusion 131 through the hinge mechanism 14 to cover the opening 1310 of the protrusion 131. Further, since the valve cover 132 is connected to the elastic member 133, the valve cover 132 can be closely attached to the protrusion 131 under the pre-tightening force of the elastic member 133, thereby achieving a tight seal of the opening 1310 of the protrusion 131.

[0093] The valve cover 132 can rotate relative to the protrusion 131 (for example, in the clockwise direction) under the impact of the cell ejecta. Thus, the valve cover 132 opens the opening 1310. At the same time, the elastic member 133 undergoes corresponding elastic deformation as the valve cover 132 rotates. When the internal pressure of the housing 200 decreases to be less than the opening pressure of the explosion-proof valve member 13, the elastic member 133 elastically returns to its original position, and the valve cover 132 rotates in the counterclockwise direction. Thus, the valve cover 132 covers the opening 1310 again.

[0094] The hinge mechanism 14 involved in the present utility model at least includes a hinge shaft and a shaft sleeve. Among them, one of the hinge shaft and the shaft sleeve is connected to the valve cover 132, and the other is connected to the protrusion 131. The shaft sleeve is rotatably sleeved on the hinge shaft, so as to realize the relative rotation of the shaft sleeve and the hinge shaft with respect to each other, and further realize the rotational connection between the valve cover 132 and the protrusion 131.

[0095] For the above-mentioned embodiment (2), some further embodiments may be as follows.

[0096] Figure 7 Some embodiments (2.1) based on embodiment (2) are exemplified. The structure of the protrusion 131 in this embodiment (2.1) may still refer to the protrusion 131 shown in Figure 3 The protrusion 131 has an upper open end 1311 and a lower open end 1312. The lower open end 1312 is connected to the cover plate 100 (i.e., the plate body 11) and communicates with the valve hole 110. The upper open end 1311 provides an opening 1310. Further, as shown in the appendix Figure 7 The valve cover 132 is hinged to the upper open end 1311 of the protrusion 131 through a hinge mechanism 14 and covers the opening 1310. The elastic member 133 is located inside the protrusion 131, and both ends of the elastic member 133 are respectively connected to the valve cover 132 and the protrusion 131.

[0097] The structure of the protrusion 131 involved in embodiment (2.1) can refer to the structure of the protrusion 131 involved in embodiment (1.1), which will not be elaborated here.

[0098] For embodiment (2.1), the upper open end 1311 of the protrusion 131 provides an opening 1310. The valve cover 132 abuts against the upper open end 1311 of the protrusion 131 and covers the opening 1310. On this basis, the upper end of the elastic member 133 is connected to the valve cover 132, and the lower end of the elastic member 133 is connected to the protrusion 131. For example, the lower open end 1312 of the protrusion 131 has an annular bottom wall, and the lower end of the elastic member 133 is connected to the annular bottom wall of the protrusion 131. Since one side of the valve cover 132 is fixedly connected to the protrusion 131, the elastic member 133 can be arranged obliquely on one side of the protrusion 131. For example, the upper end of the elastic member 133 is connected to the side of the valve cover 132 far from its hinged position, the lower end of the elastic member 133 is connected to the side of the protrusion 131 far from its hinged position, and there is an included angle between the axial direction of the elastic member 133 and the vertical direction. Thus, it is easier for the elastic member 133 to elastically deform under the drive of the valve cover 132.

[0099] Exemplarily, the elastic member 133 can be a tension spring. Based on the pre-tightening force of the tension spring itself, the valve cover 132 can closely adhere to the upper open end 1311 of the protrusion 131. That is to say, when the tension spring is in a natural state, the valve cover 132 closely adheres to the protrusion 131 to achieve reliable sealing of the opening 1310.

[0100] For embodiment (2.1), the valve cover 132 can be arranged singly. Without exclusion, the valve cover 132 can also be provided in multiple numbers, for example, symmetrically arranged in two. In this case, each valve cover 132 can be configured with a hinge mechanism 14.

[0101] The working principle of Embodiment (2.1) is as follows:

[0102] Figure 8 The open valve state of the valve cover 132 is illustrated. When thermal runaway occurs in the battery cell 300, the ejecta of the battery cell breaks through the explosion-proof valve piece 12 and enters the protrusion 131 through the valve hole 110, and then impacts the valve cover 132. Figure 8 , the valve cover 132 rotates away from the protrusion 131 to open the opening 1310 (e.g., rotate clockwise). At the same time, the elastic member 133 undergoes a tensile deformation. As the ejecta of the battery cell gradually discharges, when the internal pressure of the housing 200 drops below the opening pressure of the explosion-proof valve member 13, the elastic member 133 undergoes elastic reset and drives the valve cover 132 to reset. The valve cover 132 rotates towards the protrusion 131 to close the opening 1310 (e.g., rotate counterclockwise), and the valve cover 132 tightly adheres to the protrusion 131 again to achieve reliable sealing of the opening 1310. Thus, external air cannot enter the battery interior through the explosion-proof valve member 13.

[0103] Figure 9 Some embodiments (2.2) based on Embodiment (2) are illustrated. The structure of the protrusion 131 in this Embodiment (2.1) can still refer to Figure 3 the protrusion 131 shown in, the protrusion 131 has an upper open end 1311 and a lower open end 1312. The lower open end 1312 is connected to the cover plate 100 (i.e., the plate body 11) and is in communication with the valve hole 110, and the upper open end 1311 provides the opening 1310.

[0104] Figure 10 Further shown is Figure 9 the top view of the valve cover 132 in the closed valve state shown in, as shown in Figure 9 and Figure 10 shown, the valve cover 132 includes a support shaft 1323 connected to the opening 1310 ( Figure 9 the dotted line provided at the upper end of the protrusion 131 in refers to the upper edge of the opening 1310, and both ends of the support shaft 1323 can be respectively lapped on the upper edge of the opening 1310), the support shaft 1323 divides the opening 1310 into a first sub-opening and a second sub-opening. The valve cover 132 further includes a first sub-valve cover 1321 covering the first sub-opening and a second sub-valve cover 1322 covering the second sub-opening. The first sub-valve cover 1321 and the second sub-valve cover 1322 are respectively hinged to both sides of the support shaft 1323 through a hinge mechanism 14. The elastic member 133 is a torsion spring, the body of the torsion spring is sleeved on the support shaft 1323, one torsion arm of the torsion spring abuts against the first sub-valve cover 1321, and the other torsion arm of the torsion spring abuts against the second sub-valve cover 1322.

[0105] The structure of the protrusion 131 involved in the embodiment (2.2) can refer to the structure of the protrusion 131 involved in the embodiment (1.1), which will not be elaborated here.

[0106] The working principle of the embodiment (2.2) is as follows:

[0107] Figure 11 Further shows Figure 9 The open valve state of the shown valve cover 132. When the battery cell 300 undergoes thermal runaway, the ejecta of the battery cell breaks through the explosion-proof valve sheet 12 and enters the protrusion 131 through the valve hole 110, and then impacts the first sub-valve cover 1321 and the second sub-valve cover 1322. See Figure 11 , the first sub-valve cover 1321 and the second sub-valve cover 1322 rotate in a direction away from the protrusion 131 to respectively open the first sub-opening and the second sub-opening, that is, the opening 1310. At the same time, the elastic member 133 undergoes a torsional deformation. As the ejecta of the battery cell gradually discharges, when the internal pressure of the housing 200 drops to be less than the opening pressure of the explosion-proof valve member 13, the elastic member 133 undergoes elastic reset and drives the valve cover 132 to reset. The first sub-valve cover 1321 and the second sub-valve cover 1322 rotate in a direction close to the protrusion 131 to close the opening 1310, and the first sub-valve cover 1321 and the second sub-valve cover 1322 re-close tightly against the protrusion 131 to achieve reliable sealing of the opening 1310. Thus, external air cannot enter the battery interior through the explosion-proof valve member 13.

[0108] Regarding the above-mentioned embodiments (1) and (2), the projection of the explosion-proof valve sheet 12 on the valve cover 132 is located inside the protrusion 131. That is to say, the area of the explosion-proof valve sheet 12 is smaller than the cross-sectional area of the protrusion 131 to ensure that after the ejecta of the battery cell sprays out from the explosion-proof valve sheet 12, it smoothly and fully enters the interior of the protrusion 131.

[0109] Combined with any of the above-mentioned batteries, in some examples, as shown in the appendix Figure 4 The cover plate 100 provided by the embodiment of the present utility model further includes: a sealing ring 15, and the sealing ring 15 is arranged between the protrusion 131 and the valve cover 132.

[0110] Taking the valve cover 132 abutted against the upper opening end 1311 of the protrusion 131 as an example, a sealing ring 15 can be arranged between the valve cover 132 and the upper opening end 1311 of the protrusion 131. Among them, the sealing ring 15 can be embedded in the sealing groove on the valve cover 132, the sealing ring 15 can also be embedded in the sealing groove of the upper opening end 1311 of the protrusion 131, or the sealing ring 15 can also be embedded in the sealing grooves of both the valve cover 132 and the upper opening end 1311 of the protrusion 131, so as to realize stable positioning of the sealing ring 15. In addition, the sealing ring 15 involved in the embodiment of the present utility model can at least withstand high temperatures to prevent being damaged by the high-temperature ejecta of the battery cell.

[0111] By providing a sealing ring 15 between the protrusion 131 and the valve cover 132, the gap between the valve cover 132 and the protrusion 131 can be effectively sealed, ensuring reliable sealing of the valve cover 132 to the protrusion 131 and improving the sealing effect of the explosion-proof valve member 13. Especially when the valve cover 132 automatically returns to the position covering the opening 1310 under the action of the elastic member 133 and cannot be manually pressed tightly, the presence of the sealing ring 15 can ensure reliable sealing between the valve cover 132 and the protrusion 131 in this case.

[0112] Combined with any of the above-mentioned batteries, in some examples, the protrusion 131 and the cover plate 100 (i.e., the metal cover plate 101) are mutually limited in the direction parallel to the cover plate 100 through a limiting structure. As shown in the appendix Figure 3 As shown, the limiting structure includes a limiting groove 111, and further may include a boss. Among them, the limiting groove 111 can be formed on the surface of one of the protrusion 131 and the metal cover plate 101 of the plate body 11, and the boss can be formed on the surface of one of the protrusion 131 and the metal cover plate 101 or can also be provided by the end of the protrusion 131. The boss is embedded in the limiting groove 111, so that the protrusion 131 and the cover plate 100 are mutually limited in the direction parallel to the cover plate 100, improving the assembly stability of the explosion-proof valve member 13 on the cover plate 100.

[0113] For example, the limiting structure includes a limiting groove 111. The limiting groove 111 is opened on the surface of the plate body 11 facing away from the battery cell 300 and is communicated with the valve hole 110. The shape of the limiting groove 111 is adapted to the shape of the lower end of the protrusion 131. The lower end of the protrusion 131 serves as a boss and is adaptively embedded in the limiting groove 111, so that the protrusion 131 and the cover plate 100 are mutually limited in the direction parallel to the cover plate 100. Moreover, the arrangement of this limiting structure is simple and convenient to operate. At the same time, the presence of the limiting groove 111 also helps to reduce the assembly height of the explosion-proof valve member 13 in the battery.

[0114] In some examples, the height of the explosion-proof valve member 13 (the dimension of the explosion-proof valve member 13 in the direction perpendicular to the cover plate 100) can be 2 mm to 100 mm, further can be 5 mm to 30 mm, and even further can be 10 mm to 20 mm, so as to ensure that the battery size is more compact on the basis of ensuring the self-effect of the explosion-proof valve member 13.

[0115] As described above, the plate body 11 includes a metal cover plate 101 and an insulating partition 102 connected to one side of the metal cover plate 101 facing the battery cell 300. The explosion-proof valve sheet 12, the protrusion 131, and the metal cover plate 101 can all be made of high-temperature resistant metal materials. The explosion-proof valve sheet 12 can be welded to the metal cover plate 101, and the protrusion 131 and the metal cover plate 101 are welded together. Thus, the explosion-proof valve sheet 12 and the explosion-proof valve member 13 form an integrated valve-equipped cover plate structure with the metal cover plate 101, which not only helps improve the structural stability of the cover plate 100 but also helps improve the sealing performance of the explosion-proof valve member 13 and reduce the failure probability such as air leakage.

[0116] In some examples, in combination with the above-mentioned implementation schemes (1) and (2), as shown in the appendix Figure 3 it can be seen that a limiting groove 111 can be provided on the surface of the metal cover plate 101 facing away from the battery cell 300. The lower end of the protrusion 131 is fittingly embedded in the limiting groove 111 and welded (that is, the wall of the lower end of the protrusion 131 is welded to the wall of the limiting groove 111), so that the protrusion 131 is stably assembled on the metal cover plate 101. Another limiting groove can be provided on the side of the metal cover plate 101 facing the insulating partition 102. The explosion-proof valve sheet 12 is received in the other limiting groove and welded, so that the explosion-proof valve sheet 12 closes the valve hole 110.

[0117] For any battery involved in the embodiments of the present invention, its types include but are not limited to: lithium-ion batteries, sodium-ion batteries, lithium-air batteries, potassium-ion batteries, etc.

[0118] It should be noted that the battery cell 300 of the battery can include a bare battery cell and an insulating diaphragm coated on the outside of the bare battery cell. A negative electrode tab and a positive electrode tab are provided at the top of the bare battery cell. As shown in the appendix Figure 1 it can be seen that the plate body 11 of the cover plate 100 also has a negative electrode post 16 and a positive electrode post 17, and the negative electrode post 16 and the positive electrode post 17 are electrically connected to the negative electrode tab and the positive electrode tab of the battery cell 300 respectively.

[0119] Any battery involved in the embodiments of the present utility model can be assembled in the following assembly manner: Prepare the cover plate 100, which includes: preparing the plate body 11 by means of die stamping or the like, assembling the negative electrode post 16 and the positive electrode post 17 on the plate body 11, and welding the explosion-proof valve piece 12 on the plate body 11. Prepare the protrusion 131 by means of die stamping, machining or the like, and assemble the elastic member 133, the valve cover 132 and the optional sealing ring 15 to the corresponding positions of the protrusion 131 to prepare the explosion-proof valve member 13. Assemble the explosion-proof valve member 13 to the plate body 11. For example, embed the protrusion 131 into the limiting groove 111 on the plate body 11 and weld it to finally prepare the cover plate 100. Connect the negative electrode tab and the positive electrode tab of the battery cell 300 to the negative electrode post 16 and the positive electrode post 17 on the cover plate 100 respectively, and then assemble them into the housing 200 to prepare the battery.

[0120] On the other hand, the embodiments of the present utility model further provide a battery pack. As shown in the attached Figure 13 figure, the battery pack includes a plurality of the above-mentioned batteries 001, and the plurality of batteries 001 are connected in series or in parallel. The battery pack provided by the embodiments of the present utility model has all the advantages of the above-mentioned battery 001 and will not be elaborated herein.

[0121] Generally, the battery pack includes a metal housing, components such as a battery module, a cold plate assembly, and electrical components located inside the metal housing. The battery module includes a plurality of batteries 001 connected in series or in parallel. As shown in the attached Figure 13 figure, a smoke exhaust channel 002 is usually provided in the battery pack. For example, the gap between the top of the battery module and the top wall of the metal housing of the battery pack is used as the smoke exhaust channel 002, and a battery pack explosion-proof valve is provided on the side wall of the metal housing of the battery pack. The smoke exhaust channel 002 is used to collect the battery cell eruption products. When the pressure inside the smoke exhaust channel 002 reaches the set value, the battery pack explosion-proof valve opens, so that the battery cell eruption products are discharged to the outside of the battery pack.

[0122] The battery pack provided by the embodiments of the present utility model, as shown in the attached Figure 13 figure, has a smoke exhaust channel 002, and the explosion-proof valve member 13 extends into the smoke exhaust channel 002, so that the valve cover 132 of the explosion-proof valve member 13 and the opening 1310 of the protrusion 131 are located inside the smoke exhaust channel 002. Of course, part of the protrusion 131 can also be located inside the smoke exhaust channel 002, which can realize the directional discharge of the battery cell eruption products. When a certain battery cell 300 in the battery pack is thermally out of control, the high-temperature flue gas, electrolyte, solid particles and other battery cell eruption products ejected by the out-of-control battery cell 300 are directly discharged into the smoke exhaust channel 002 from the opening 1310 of the protrusion 131, and finally discharged to the outside of the battery 001 through the battery pack explosion-proof valve, avoiding the corrosion of other components such as the negative electrode post 16 and the positive electrode post 17 by the high-temperature steam.

[0123] On the other hand, an embodiment of the present disclosure further provides an energy storage system, which includes a power converter and at least one of the above-mentioned battery packs; the power converter is configured to perform power conversion on the voltage output by the battery pack and output it to the power grid or load, and / or perform power conversion on the voltage output by an external power source and output it to the battery pack.

[0124] The energy storage system provided by the embodiment of the present disclosure has all the advantages of the battery or battery pack provided by the embodiment of the present disclosure, which will not be elaborated here.

[0125] The above description is only for the convenience of those skilled in the art to understand the technical solution of the present invention, and is not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A battery, characterized in that, The battery includes a cover plate (100), a battery cell (300), and a housing (200) for accommodating the battery cell (300), and the cover plate (100) covers the housing (200); The cover plate (100) is provided with a valve hole (110), an explosion-proof valve sheet (12) is installed in the valve hole (110), a protrusion (131) is provided on the surface of the cover plate (100) facing away from the battery cell (300), the protrusion (131) is arranged around the outer periphery of the valve hole (110) to form a cavity, an opening (1310) is provided in the cavity, the opening (1310) is communicated with the valve hole (110), a valve cover (132) is provided at the opening (1310), the valve cover (132) seals the opening (1310), and the valve cover (132) is connected with an elastic member (133); When the internal pressure of the housing (200) is greater than or equal to a first threshold value, the explosion-proof valve sheet (12) ruptures, and the valve cover (132) moves away from the opening (1310) and deforms the elastic member (133); When the internal pressure of the housing (200) is less than or equal to a second threshold value, the elastic member (133) is used to move the valve cover (132) towards the opening (1310) and seal the opening (1310).

2. The battery according to claim 1, wherein, The elastic member (133) has a pre-tightening force, and the pre-tightening force of the elastic member (133) is greater than the external atmospheric pressure and less than or equal to the first threshold value.

3. The battery according to claim 1, wherein, The valve cover (132) abuts against the protrusion (131) through the elastic member (133), and the force application direction of the elastic member (133) on the valve cover (132) is perpendicular to the valve cover (132), so that the valve cover (132) moves translationally along the axial direction of the protrusion (131) to open or close the opening (1310).

4. The battery according to claim 3, characterized in that, The protrusion (131) has an upper open end (1311) and a lower open end (1312), the lower open end (1312) is connected to the cover plate (100) and is communicated with the valve hole (110), and the upper open end (1311) provides the opening (1310); The valve cover (132) abuts against the upper open end (1311) of the protrusion (131) and covers the opening (1310), the elastic member (133) is located inside the protrusion (131), and both ends of the elastic member (133) are respectively connected to the valve cover (132) and the protrusion (131).

5. The battery according to claim 3, characterized in that, The protrusion (131) has an upper open end (1311) and a lower open end (1312), the lower open end (1312) is connected to the cover plate (100) and is communicated with the valve hole (110), and the lower open end (1312) provides the opening (1310); The valve cover (132) abuts against the lower opening end (1312) of the protrusion (131) and covers the opening (1310). The elastic member (133) is located inside the protrusion (131), and both ends of the elastic member (133) are respectively connected to the valve cover (132) and the protrusion (131).

6. The battery according to claim 1, wherein The valve cover (132) is connected to the protrusion (131) through a hinge mechanism (14), such that the valve cover (132) rotates about the hinge mechanism (14) as a rotation axis, and the rotation axis of the valve cover (132) is skew perpendicular to the axis of the protrusion (131) to open or close the opening (1310).

7. The battery according to claim 6, characterized in that, The protrusion (131) has an upper opening end (1311) and a lower opening end (1312). The lower opening end (1312) is connected to the cover plate (100) and is in communication with the valve hole (110), and the upper opening end (1311) provides the opening (1310). The valve cover (132) is hinged to the upper opening end (1311) of the protrusion (131) through a hinge mechanism (14) and covers the opening (1310). The elastic member (133) is located inside the protrusion (131), and both ends of the elastic member (133) are respectively connected to the valve cover (132) and the protrusion (131).

8. The battery according to claim 6, characterized in that The protrusion (131) has an upper opening end (1311) and a lower opening end (1312). The lower opening end (1312) is connected to the cover plate (100) and is in communication with the valve hole (110), and the upper opening end (1311) provides the opening (1310). The valve cover (132) includes a support shaft (1323) connected to the opening (1310). The support shaft (1323) divides the opening (1310) into a first sub-opening and a second sub-opening. The valve cover (132) further includes a first sub-valve cover (1321) covering the first sub-opening and a second sub-valve cover (1322) covering the second sub-opening. The first sub-valve cover (1321) and the second sub-valve cover (1322) are respectively hinged to both sides of the support shaft (1323) through a hinge mechanism (14). The elastic member (133) is a torsion spring. The body of the torsion spring is sleeved on the support shaft (1323). One torsion arm of the torsion spring abuts against the first sub-valve cover (1321), and the other torsion arm of the torsion spring abuts against the second sub-valve cover (1322).

9. The battery according to any one of claims 1-8, characterized in that, The cover plate (100) further includes: a sealing ring (15), and the sealing ring (15) is disposed between the protrusion (131) and the valve cover (132).

10. The battery according to any one of claims 1-8, characterized in that, One side surface of the cover plate (100) facing away from the battery cell (300) has a limiting groove (111), and the lower end portion of the protrusion (131) is embedded in the limiting groove (111).

11. The battery according to any one of claims 1-8, characterized in that, The cover plate (100) includes a metal cover plate (101) and an insulating partition plate (102) connected to one side of the metal cover plate (101) facing the battery cell (300). The explosion-proof valve sheet (12) is welded to the metal cover plate (101), and the protrusion (131) is welded to the metal cover plate (101).

12. A battery pack, characterized in that, The battery pack includes a plurality of batteries (001) as described in any one of claims 1-11, and the plurality of batteries (001) are connected in series or in parallel.

13. The battery pack according to claim 12, characterized in that, The battery pack has a smoke exhaust channel (002), and the protrusion (131) extends into the smoke exhaust channel (002) such that the valve cover (132) and the opening (1310) of the protrusion (131) are located inside the smoke exhaust channel (002).

14. An energy storage system, characterized in that, The energy storage system includes a power converter and at least one battery pack as described in claim 12 or 13; The power converter is configured to perform power conversion on the voltage output by the battery pack and output it to the power grid or a load, and / or perform power conversion on the voltage output by an external power source and output it to the battery pack.

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