Battery cap and battery

Abstract

The utility model relates to the technical field of battery equipment, in particular to a battery cap and a battery. A battery cap in the battery comprises a top cap, a pressure relief valve plate, a power-off pore plate and a sealing ring, the top cap, the pressure relief valve plate and the power-off pore plate are sequentially stacked in a containing cavity of the sealing ring, and welding equipment can weld three welding spots on a weak part of the power-off pore plate so as to weld and fix the weak part and the pressure relief valve plate. The three welding spots are not located in the same straight line, the weak part is driven by the protrusion of the pressure release valve plate to protrude outwards relative to the power-off pore plate, so that the weak part is disconnected with the power-off pore plate or the three welding spots used for connecting the weak part with the pressure release valve plate are disconnected, and power-off of the battery roll core and an external butt joint device is achieved. The anti-torsion rigidity can be effectively improved, meanwhile, the welding difficulty of the weak part and the pressure release valve plate is reduced to the maximum extent, the welding efficiency is improved, and the actual requirement is met.

Description

Technical Field

[0001] The utility model relates to the technical field of battery equipment, in particular to a battery cap and a battery. Background Art

[0002] With the continuous development of battery technology and the continuous improvement of people's needs, batteries are gradually developing in the direction of high density and large capacity. For high-density and large-capacity batteries, the safety requirements are more stringent. When the battery cell fails (such as overheating, short circuit, overcharging, etc.), a lot of gas will be generated inside the battery. If the generated gas cannot be discharged from the battery in time, the battery will swell or even explode.

[0003] To ensure the safety of battery use, a CID (current interrupt device) needs to be set on the battery cap. When the internal pressure of the battery increases to a preset value, the CID will cut off the circuit loop inside the battery and prevent the electrochemical reaction of the battery cell from continuing.

[0004] In the prior art, CID usually includes a pressure relief valve plate and a power-off orifice plate, wherein the welding between the pressure relief valve plate and the power-off orifice plate is usually single-spot welding. During battery quality inspection or when the battery is bumped, the power-off orifice plate is easily broken due to the torsional force, causing battery failure and unnecessary losses. In order to improve the torsional stiffness between the pressure relief valve plate and the power-off orifice plate, ring welding is performed between the pressure relief valve plate and the power-off orifice plate. However, although the ring welding method can improve the torsional stiffness between the pressure relief valve plate and the power-off orifice plate, the welding is difficult and the welding efficiency is low, which cannot meet actual production needs.

[0005] Therefore, it is urgent to invent a battery cap and a battery to solve the above problems. Utility Model Content

[0006] The utility model aims to provide a battery cap and a battery, so as to improve the torsional rigidity between the pressure relief valve sheet and the power-off orifice plate, reduce the welding difficulty and improve the welding efficiency.

[0007] To achieve this purpose, the utility model adopts the following technical solutions:

[0008] Battery cap, including top cap, pressure relief valve plate, power-off orifice plate and sealing ring;

[0009] The top cap, the pressure relief valve plate and the power-off orifice plate are stacked in sequence in the accommodating cavity of the sealing ring;

[0010] The welding equipment can weld three welding points on the weak part of the power-off orifice plate to weld and fix the weak part to the pressure relief valve plate, and the three welding points are not located in the same straight line.

[0011] As a preferred embodiment, a supporting portion extending radially inward is provided at one axial end of the sealing ring, the power-off orifice plate is overlapped on the supporting portion, and an annular protrusion extending outward is provided on one end face of the supporting portion away from the power-off orifice plate.

[0012] As a preferred solution, the vertical distance between the outwardly extending end of the annular protrusion and the end surface of the supporting portion away from the power-off orifice plate is 1 mm to 3 mm.

[0013] As a preferred solution, the battery cap further includes:

[0014] An insulating gasket is sandwiched between the pressure relief valve plate and the power-off orifice plate. A docking protrusion is provided on the lower end surface of the pressure relief valve plate. The docking protrusion passes through the insulating gasket and is welded and fixed to the weak portion.

[0015] As a preferred solution, the thickness of the insulating gasket is 0.5 mm to 1 mm, and the lower end surface of the docking protrusion is flush with the lower end surface of the insulating gasket.

[0016] As a preferred solution, the diameter of each welding spot is 0.5 mm to 1 mm.

[0017] As a preferred solution, an equilateral triangle can be formed with the three welding points as vertices, the weak portion is a circle, and the center of the equilateral triangle formed by the three welding points coincides with the center of the circle of the weak portion.

[0018] As a preferred solution, the three welding points are welded by a one-time welding fixation method or are welded sequentially by separate welding fixation methods.

[0019] As a preferred solution, a plurality of ventilation holes are arranged on the power-off orifice plate, and the plurality of ventilation holes are arranged at intervals with the weak portion as the center.

[0020] A battery, comprising a battery core, an electrolyte, a battery shell, a battery cover and the battery cap as described above, wherein the battery core and the electrolyte are both contained in the battery shell, the battery cap is arranged on the battery cover, the power-off hole plate in the battery cap can be fixed to the pole ear of the battery core, the top cap in the battery cap can be fixed to an external docking device, and the battery cover is used to seal the battery shell containing the battery core and the electrolyte.

[0021] Beneficial effects of the utility model:

[0022] The battery cap provided by the utility model realizes the insulation accommodation of the top cap, the pressure relief valve sheet and the power-off orifice plate by stacking the top cap, the pressure relief valve sheet and the power-off orifice plate in sequence in the accommodating chamber of the sealing ring, and three welding points are welded at the weak part of the power-off orifice plate by welding equipment to ensure the welding and fixation of the weak part and the pressure relief valve sheet. When the battery coil core in the battery generates gas due to failure, the gas expands and squeezes the pressure relief valve sheet, driving the pressure relief valve sheet to bulge outward. Since the weak part is welded and fixed to the pressure relief valve sheet, the pressure relief valve sheet will drive the weak part to bulge relative to the pressure relief valve sheet. The power-off orifice plate protrudes outward, so that the weak portion is disconnected from the power-off orifice plate or the three welding points connecting the weak portion and the pressure relief valve sheet are disconnected, thereby disconnecting the power supply to the battery roll core and the external docking device, and preventing the electrochemical reaction of the battery roll core from proceeding. Moreover, since there are three welding points between the weak portion and the pressure relief valve sheet, and the three welding points are not located in the same straight line, if the three welding points are used as vertices, a triangle can be formed. Compared with the prior art, it can effectively improve its torsional stiffness while reducing the difficulty of welding the weak portion and the pressure relief valve sheet to the greatest extent.

[0023] The utility model also provides a battery. By applying the above-mentioned battery cap, when the battery core inside the battery generates gas due to failure, the gas expands and squeezes the pressure relief valve plate, driving the pressure relief valve plate to bulge outward. Since the weak portion is welded and fixed to the pressure relief valve plate, the pressure relief valve plate will drive the weak portion to bulge outward relative to the power-off orifice plate, so that the weak portion is disconnected from the power-off orifice plate or the three welding points used to connect the weak portion and the pressure relief valve plate are disconnected, thereby disconnecting the power of the battery core and the external docking device, and preventing the electrochemical reaction of the battery core from occurring. Moreover, since there are three welding points between the weak portion and the pressure relief valve plate, and the three welding points are not located in the same straight line, a triangle can be formed with the three welding points as vertices. Compared with the prior art, it is possible to effectively improve its torsional rigidity while reducing the difficulty of welding the weak portion to the pressure relief valve plate to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a cross-sectional schematic diagram of a battery cap provided by an embodiment of the utility model;

[0025] Figure 2 It is a bottom view of the battery cap provided by the embodiment of the utility model.

[0026] In the figure:

[0027] 1. Soldering points;

[0028] 1000, battery cap;

[0029] 100, power-off hole plate; 110, weak part; 120, vent hole;

[0030] 200, pressure relief valve plate; 210, docking protrusion;

[0031] 300, sealing ring; 310, supporting portion; 311, annular protrusion;

[0032] 400, top hat;

[0033] 500. Insulating gasket. DETAILED DESCRIPTION

[0034] In order to make the technical problems solved by the present invention, the technical solutions adopted and the technical effects achieved more clearly, the technical solutions of the present invention are further explained below with reference to the accompanying drawings and through specific implementation methods.

[0035] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0037] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0038] In the prior art, CID usually includes a pressure relief valve plate and a power-off orifice plate, wherein the welding between the pressure relief valve plate and the power-off orifice plate is single-spot welding, and the torsional stiffness of the spot welding is low. During battery quality inspection or when the battery is bumped, the power-off orifice plate is easily broken due to the torsional force, resulting in battery failure and unnecessary losses. In order to improve the torsional stiffness between the pressure relief valve plate and the power-off orifice plate, ring welding is performed between the pressure relief valve plate and the power-off orifice plate. However, although the ring welding method can improve the torsional stiffness between the pressure relief valve plate and the power-off orifice plate, the welding is difficult and the welding efficiency is low, which cannot meet the actual production needs.

[0039] In order to solve the above problems, Figure 1 and Figure 2 As shown, this embodiment provides a battery cap 1000. The battery cap 1000 includes a top cap 400, a pressure relief valve sheet 200, a power-off orifice plate 100, and a sealing ring 300, wherein the top cap 400, the pressure relief valve sheet 200, and the power-off orifice plate 100 are sequentially stacked and arranged in the accommodating cavity of the sealing ring 300, and the welding equipment can weld three welding points 1 at the weak portion 110 of the power-off orifice plate 100 to weld and fix the weak portion 110 to the pressure relief valve sheet 200, and the three welding points 1 are not located in the same straight line.

[0040] The battery cap 1000 is stacked in the receiving chamber of the sealing ring 300 with the top cap 400, the pressure relief valve sheet 200 and the power-off orifice plate 100 in sequence to achieve insulation accommodation of the top cap 400, the pressure relief valve sheet 200 and the power-off orifice plate 100. Three welding points 1 are welded at the weak portion 110 of the power-off orifice plate 100 by welding equipment to ensure that the weak portion 110 and the pressure relief valve sheet 200 are welded and fixed. When the battery coil core in the battery generates gas due to failure, the gas expands and squeezes the pressure relief valve sheet 200, driving the pressure relief valve sheet 200 to bulge outward. Since the weak portion 110 and the pressure relief valve sheet 200 are welded and fixed, the pressure relief valve sheet 200 will drive The weak portion 110 protrudes outward relative to the power-off orifice plate 100, so that the weak portion 110 is disconnected from the power-off orifice plate 100 or the three welding points 1 used to connect the weak portion 110 and the pressure relief valve plate 200 are disconnected, thereby disconnecting the power supply between the battery roll core and the external docking device and preventing the electrochemical reaction of the battery roll core from proceeding. In addition, since there are three welding points 1 between the weak portion 110 and the pressure relief valve plate 200, and the three welding points 1 are not located in the same straight line, if the three welding points 1 are used as vertices, a triangle can be formed. Compared with the prior art, it is possible to effectively improve its torsional stiffness while minimizing the difficulty of welding the weak portion 110 and the pressure relief valve plate 200.

[0041] It should be noted that when the pressure relief valve sheet 200 drives the weak portion 110 to bulge outward relative to the power-off orifice plate 100, if the breaking tensile force threshold between the three welding points 1 is greater than the breaking tensile force threshold of the weak portion 110 relative to the power-off orifice plate 100, the weak portion 110 is first disconnected relative to the power-off orifice plate 100. If the breaking tensile force threshold between the three welding points 1 is less than the breaking tensile force threshold of the weak portion 110 relative to the power-off orifice plate 100, the three welding points 1 are first disconnected relative to the weak portion 110 and the pressure relief valve sheet 200. If the breaking tensile force threshold between the three welding points 1 is equal to the breaking tensile force threshold of the weak portion 110 relative to the power-off orifice plate 100, the three welding points 1 are disconnected relative to the weak portion 110 and the pressure relief valve sheet 200, and the weak portion 110 is disconnected relative to the power-off orifice plate 100.

[0042] A stress analysis is performed on the pole ear, weak portion 110 and pressure relief valve sheet 200 of the battery roll core. Three welding points 1 are arranged between the weak portion 110 and the pressure relief valve sheet 200, and a triangle can be formed with the three welding points 1 as vertices. When the pole ear of the battery roll core is welded and fixed to the lower end surface of the power-off orifice plate 100, the three welding points 1 that are not located in the same straight line will not form a lever structure with the welding position of the pole ear of the battery roll core and the lower end surface of the power-off orifice plate 100, thereby improving its torsional stiffness.

[0043] In this embodiment, the three welding points 1 as vertices can form an equilateral triangle to further improve the torsional rigidity of the three welding points 1. In other embodiments, the relative positions of the three welding points 1 can be adjusted arbitrarily according to actual needs, and it is only necessary to ensure that the three welding points 1 are not located in the same straight line, which is not specifically limited in this embodiment.

[0044] Furthermore, the weak portion 110 is circular, and the center of the equilateral triangle formed by the three welding points 1 coincides with the center of the weak portion 110. By setting the weak portion 110 to be circular and ensuring that the center of the equilateral triangle formed by the three welding points 1 coincides with the center of the circular weak portion 110, the torsional rigidity of the weak portion 110 can be further improved.

[0045] Preferably, a plurality of vent holes 120 are provided on the power-off orifice plate 100, and the plurality of vent holes 120 are arranged at intervals with the weak portion 110 as the center of the circle. By arranging a plurality of vent holes 120 on the power-off orifice plate 100 with the weak portion 110 as a circular interval, it is possible to further facilitate the gas inside the battery to drive the pressure relief valve sheet 200 to bulge outward, thereby ensuring the normal pressure relief of the pressure relief valve sheet 200. It should be noted that, in the present embodiment, four vent holes 120 are provided on the power-off orifice plate 100, and the four vent holes 120 are arranged at equal intervals with the weak portion 110 as the center of the circle, thereby improving the aesthetics of the power-off orifice plate 100. In other embodiments, the number of vent holes 120 on the power-off orifice plate 100 can also be adjusted according to actual needs, and the plurality of vent holes 120 can also be arranged at unequal intervals with the weak portion 110 as the center of the circle, which is not specifically limited in the present embodiment. In addition, the specific shape of the vent hole 120 can be circular, rectangular or any shape, which is not specifically limited in the present embodiment.

[0046] In this embodiment, the three welding points 1 are welded by a one-time welding fixation method. By welding and fixing the three welding points 1 as a whole, the welding efficiency of the weak portion 110 and the pressure relief valve plate 200 can be further improved. In other embodiments, the welding equipment can also weld the three welding points 1 between the weak portion 110 and the pressure relief valve plate 200 in sequence, which is not specifically limited in this embodiment.

[0047] Specifically, the diameter of each solder joint 1 is 0.5 mm to 1 mm. In this embodiment, the diameter of each solder joint 1 is preferably 0.75 mm. In other embodiments, the specific diameter of the solder joint 1 can be adjusted arbitrarily within the range of 0.5 mm to 1 mm, and this embodiment does not make any specific limitation.

[0048] Preferably, a supporting portion 310 extending radially inward is provided at one axial end of the sealing ring 300, and the power-off orifice plate 100 is overlapped on the supporting portion 310. An annular protrusion 311 extending outward is provided on one end surface of the supporting portion 310 away from the power-off orifice plate 100, and the annular protrusion 311 is used to limit the limit position of the battery roll core expanding upward. By providing an annular protrusion 311 extending outward at one end of the supporting portion 310 away from the power-off orifice plate 100, when the battery roll core expands, the limit position of the battery roll core expanding in the direction close to the power-off orifice plate 100 is abutting against the annular protrusion 311, and the battery roll core will not abut against the supporting portion 310 and the power-off orifice plate 100, thereby avoiding the failure of the battery that can be used normally due to the weak portion 110 on the power-off orifice plate 100 being broken off by the power-off orifice plate 100 after the battery roll core expands upward, thereby improving the protection of the power-off orifice plate 100 and the battery.

[0049] It should be noted that, in the present embodiment, the battery cap 1000 is placed vertically, the lower end face of the power-off orifice plate 100 faces downward, the battery roll core is arranged below the power-off orifice plate 100, the upper end face of the battery roll core is directly opposite to the power-off orifice plate 100, and the lower end face of the supporting portion 310 is provided with an annular protrusion 311 extending vertically downward. In other embodiments, the battery cap 1000 and the battery roll core may also be placed horizontally or tilted, and it is only necessary to ensure that the power-off orifice plate 100 is directly opposite to the battery roll core, which is not specifically limited in the present embodiment. In addition, the annular protrusion 311 extends in the direction close to the battery roll core and tilts at any angle, which is not specifically limited in the present embodiment.

[0050] Furthermore, the vertical distance between the end of the annular protrusion 311 extending outward and the end face of the supporting portion 310 away from the power-off orifice plate 100 is 1 mm to 3 mm. It should be noted that in this embodiment, since the battery cap 1000 is placed vertically, the lower end face of the power-off orifice plate 100 faces downward, the battery roll core is arranged below the power-off orifice plate 100, and the upper end face of the battery roll core is directly opposite to the power-off orifice plate 100, the annular protrusion 311 extends downward, and the distance that the annular protrusion 311 extends downward from the lower end face of the supporting portion 310 is preferably 2 mm. In other embodiments, the vertical distance between the end of the annular protrusion 311 extending outward and the end face of the supporting portion 310 away from the power-off orifice plate 100 can be arbitrarily adjusted within the range of 1 mm to 3 mm, and this embodiment does not make specific limitations.

[0051] In order to improve the pressure relief accuracy of the pressure relief valve plate 200, the battery cap 1000 also includes an insulating gasket 500, wherein the insulating gasket 500 is clamped between the pressure relief valve plate 200 and the power-off orifice plate 100, and the lower end surface of the pressure relief valve plate 200 is provided with a docking protrusion 210, which passes through the insulating gasket 500 and is welded and fixed to the weak part 110. By arranging a docking protrusion 210 on the lower end surface of the pressure relief valve plate 200, and utilizing the docking protrusion 210 to weld and fix to the weak portion 110 in the power-off orifice plate 100, utilizing the gap between the pressure relief valve plate 200 and the power-off orifice plate 100 can further facilitate the pressure relief valve plate 200 to drive the weak portion 110 to disconnect from the power-off orifice plate 100, and sandwiching an insulating gasket 500 between the pressure relief valve plate 200 and the power-off orifice plate 100, so that the docking protrusion 210 passes through the insulating gasket 500 and is welded and fixed to the weak portion 110. The structure is compact and the design is ingenious, and the stable docking of the pressure relief valve plate 200 and the power-off orifice plate 100 can be ensured on the basis of increasing the gap between the pressure relief valve plate 200 and the power-off orifice plate 100. It should be noted that in this embodiment, since the weak portion 110 is circular, in order to ensure the docking effect between the docking protrusion 210 and the weak portion 110, the docking protrusion 210 is also circular and extends downward from the lower end surface of the pressure relief valve plate 200. The docking protrusion 210 and the weak portion 110 are concentrically arranged and the circular cross-sectional areas of the two are equal, so as to further facilitate the docking protrusion 210 to drive the weak portion 110 to disconnect from the power-off orifice plate 100. In other embodiments, the specific shape of the docking protrusion 210 can also be adjusted according to actual needs, and this embodiment does not make a specific limitation.

[0052] In addition, the pressure relief valve plate 200 is provided with a plurality of scratches, which are arranged at equal intervals with the docking protrusion 210 as the center, which can not only improve the aesthetics of the pressure relief valve plate 200, but also facilitate the pressure expansion of the pressure relief valve plate 200. It should be noted that in this embodiment, the pressure relief valve plate 200 is provided with 4 scratches arranged at equal intervals with the docking protrusion 210 as the center, and each scratch extends outward with the docking protrusion 210 as the center. In other embodiments, the number of scratches and the extension direction of each scratch can also be adjusted according to actual needs, and this embodiment does not specifically limit it.

[0053] Furthermore, the thickness of the insulating gasket 500 is 0.5 mm to 1 mm, and the lower end surface of the docking protrusion 210 is flush with the lower end surface of the insulating gasket 500. By limiting the thickness of the insulating gasket 500 and ensuring that the lower end surface of the docking protrusion 210 is flush with the lower end surface of the insulating gasket 500, it can be ensured that the docking protrusion 210 can easily drive the weak part 110 to reduce the overall height of the battery cap 1000. It should be noted that in this embodiment, the thickness of the insulating gasket 500 is 0.75 mm, and accordingly, the distance that the docking protrusion 210 extends downward from the lower end surface of the pressure relief valve plate 200 is 0.75 mm. In other embodiments, the thickness of the insulating gasket 500 can also be adjusted within the range of 0.5 mm to 1 mm according to actual needs, and this embodiment does not make specific limitations.

[0054] This embodiment also provides a battery. The battery includes a battery core, an electrolyte, a battery shell, a battery cover, and the battery cap 1000. The battery core and the electrolyte are both contained in the battery shell. The battery cap 1000 is disposed on the battery cover. The power-off hole plate 100 in the battery cap 1000 can be fixed to the pole ear of the battery core. The top cap 400 in the battery cap 1000 can be fixed to an external docking device. The battery cover is used to seal the battery shell containing the battery core and the electrolyte.

[0055] The battery uses the battery cap 1000. When the battery core in the battery generates gas due to failure, the gas expands and squeezes the pressure relief valve sheet 200, driving the pressure relief valve sheet 200 to bulge outward. Since the weak portion 110 on the power-off orifice plate 100 is welded and fixed to the butt protrusion 210 on the pressure relief valve sheet 200, the butt protrusion 210 will drive the weak portion 110 to bulge outward relative to the power-off orifice plate 100, so that the weak portion 110 is disconnected from the power-off orifice plate 100 or is used to connect the weak portion 110 with the pressure relief valve sheet 200. The three welding points 1 of the pressure relief valve sheet 200 are disconnected, thereby disconnecting the power supply to the battery core and the external docking device, thereby preventing the electrochemical reaction of the battery core from proceeding. In addition, since there are three welding points 1 between the weak portion 110 and the docking protrusion 210, and the three welding points 1 are not located in the same straight line, a triangle can be formed with the three welding points 1 as vertices. Compared with the prior art, the torsional stiffness can be effectively improved while the welding difficulty between the weak portion 110 and the docking protrusion 210 can be reduced to the greatest extent.

[0056] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A battery cap, characterized in that: It comprises a top cap (400), a pressure relief valve plate (200), a power-off orifice plate (100) and a sealing ring (300); The top cap (400), the pressure relief valve plate (200) and the power-off orifice plate (100) are stacked in sequence and arranged in the accommodating cavity of the sealing ring (300); The welding equipment can weld three welding points (1) on the weak portion (110) of the power-off orifice plate (100) to weld and fix the weak portion (110) to the pressure relief valve plate (200), and the three welding points (1) are not located in the same straight line.

2. The battery cap according to claim 1, characterized in that: A supporting portion (310) extending radially inward is provided at one axial end of the sealing ring (300), the power-off orifice plate (100) is overlapped on the supporting portion (310), and an annular protrusion (311) extending outward is provided on an end surface of the supporting portion (310) away from the power-off orifice plate (100).

3. The battery cap according to claim 2, characterized in that: The vertical distance between the outwardly extending end of the annular protrusion (311) and the end surface of the supporting portion (310) away from the power-off orifice plate (100) is 1 mm to 3 mm.

4. The battery cap according to claim 1, characterized in that: The battery cap further comprises: an insulating gasket (500), the insulating gasket (500) being sandwiched between the pressure relief valve plate (200) and the power-off orifice plate (100), the lower end surface of the pressure relief valve plate (200) being provided with a docking protrusion (210), the docking protrusion (210) passing through the insulating gasket (500) and then being welded and fixed to the weak portion (110).

5. The battery cap according to claim 4, characterized in that: The thickness of the insulating gasket (500) is 0.5 mm to 1 mm, and the lower end surface of the butt protrusion (210) is flush with the lower end surface of the insulating gasket (500).

6. The battery cap according to claim 1, characterized in that: The diameter of each welding spot (1) is 0.5 mm to 1 mm.

7. The battery cap according to claim 6, characterized in that: An equilateral triangle can be formed with the three welding points (1) as vertices, the weak portion (110) is a circle, and the center of the equilateral triangle formed by the three welding points (1) coincides with the center of the circle of the weak portion (110).

8. The battery cap according to claim 1, characterized in that: The three welding points (1) are welded in a one-time welding fixation manner or welded in sequence in a separate welding fixation manner.

9. The battery cap according to claim 1, characterized in that: The power-off orifice plate (100) is provided with a plurality of vent holes (120), and the plurality of vent holes (120) are arranged at intervals with the weak portion (110) as the center.

10. A battery, characterized in that It comprises a battery core, an electrolyte, a battery shell, a battery cover and the battery cap according to any one of claims 1 to 9, wherein the battery core and the electrolyte are both contained in the battery shell, and the battery cap is arranged on the battery cover, the power-off hole plate (100) in the battery cap can be fixed to the pole ear of the battery core, the top cap (400) in the battery cap can be fixed to an external docking device, and the battery cover is used to seal the battery shell containing the battery core and the electrolyte.

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