Battery cap and battery comprising same

Abstract

The invention relates to a battery cap and a battery comprising the same. The battery cap comprises a top cover, the explosion-proof valve plate is arranged below the top cover and is electrically connected with the top cover, and the peripheral size of the explosion-proof valve plate is smaller than that of the top cover; the pore plate is arranged below the anti-explosion valve plate, the pore plate and the anti-explosion valve plate are electrically connected at the central position, and a gap is reserved between the pore plate and the anti-explosion valve plate at the peripheral position; and the inner gasket is used for sealing a gap between the explosion-proof valve plate and the periphery of the pore plate. According to the invention, the electrolyte can be effectively sealed under the normal working condition, and the pressure can be quickly and effectively released in case of emergency. Moreover, through the structural design of the cap, the overall height of the battery cap is reduced, and under the condition that the height of the battery is not changed, the roll core height and the electrolyte injection amount can be effectively improved, so that the overall capacity of the battery is improved.

Description

Technical Field

[0001] The present invention relates to the field of batteries, and in particular to a battery cap. The present invention also relates to a battery containing the cap. Background Art

[0002] Batteries are widely used in various electronic devices. They are mainly composed of caps, shells, winding cores, and electrolytes. In order to pursue higher battery capacity, the space utilization of the battery should be increased as much as possible within a certain battery volume limit to increase the amount of electrolyte injection. The battery cap is an important guarantee for battery safety. When a short circuit or failure occurs inside the battery, the gas inside the battery will increase instantly. If it cannot be discharged in time and effectively, the battery may explode. Therefore, in order to ensure the safety of the battery during use, a safe and effective explosion-proof structure needs to be designed in the cap.

[0003] The existing explosion-proof structure of the battery cap usually includes an explosion-proof valve plate and an orifice plate. In order to ensure the sealing performance during normal operation and the effective pressure relief performance in abnormal situations, the explosion-proof valve plate is usually designed to have a step structure. Under normal use, the internal electrolyte of the battery is isolated from the outside by structures such as the explosion-proof valve plate, the orifice plate, and the gasket. When an abnormality occurs and the pressure rises, the explosion-proof valve plate is allowed to break and flip, thereby achieving effective pressure relief to achieve the purpose of explosion-proof. However, in order to ensure the above steps, an excessive amount of space redundancy is usually set between the top cover and the winding core of the battery cap, thereby increasing the overall height of the cap, which in turn leads to a reduction in the effective utilization space of the battery. At the same time, in the existing battery cap design, the top cover and the explosion-proof valve plate are sealed by wire welding. If the wire welding is not firm enough, leakage is likely to occur.

[0004] Therefore, it is necessary to provide a battery cap and a battery containing the cap to at least partially solve the above problems. Summary of the invention

[0005] The present invention provides a battery cap that can achieve effective sealing of electrolyte under normal working conditions and rapid and effective pressure relief in emergency situations. In addition, the present invention reduces the overall height of the battery cap through the structural design of the cap, and can effectively increase the height of the winding core and the amount of electrolyte injection while keeping the battery height unchanged, thereby increasing the overall capacity of the battery. At the same time, the present invention also provides a battery containing the battery cap as described above.

[0006] According to one aspect of the present invention, there is provided a battery cap, comprising:

[0007] Top cover;

[0008] An explosion-proof valve plate, the explosion-proof valve plate is arranged below the top cover and is electrically connected to the top cover, and the outer circumference of the explosion-proof valve plate is smaller than the outer circumference of the top cover;

[0009] An orifice plate, the orifice plate is arranged below the explosion-proof valve plate, the orifice plate and the explosion-proof valve plate are electrically connected at the center position and are separated at the peripheral position with a gap;

[0010] An internal gasket is used to seal the gap between the explosion-proof valve plate and the outer periphery of the orifice plate.

[0011] In one embodiment, an upward groove is provided at the center of the explosion-proof valve, and a downward groove is provided at the center of the orifice plate; the downward groove is electrically connected to the upward groove; and the upward groove or the downward groove has a boss structure.

[0012] In one embodiment, the upward groove has a boss structure, and the boss structure protrudes from the lower surface of the explosion-proof valve plate; the downward groove is a pit-shaped structure formed at the center of the orifice plate.

[0013] In one embodiment, the downward groove has a boss structure, and the boss structure protrudes from the upper surface of the orifice plate; the upward groove is a pit-shaped structure formed at the center position of the explosion-proof valve plate.

[0014] In one embodiment, a sealing ring is provided between the top cover and the explosion-proof valve plate, and the sealing ring is made of elastic material.

[0015] In one embodiment, a downward annular groove is provided on the lower surface of the top cover, and an upward annular groove is provided on the upper surface of the explosion-proof valve plate. The space formed by closing the downward annular groove and the upward annular groove is used to accommodate the sealing ring.

[0016] In one embodiment, the cross-sections of the downward annular groove and the upward annular groove are both isosceles triangles or semicircles, and the downward annular groove and the upward annular groove form a diamond structure or a circular structure when closed; preferably, the cross-sections of the downward annular groove and the upward annular groove are both isosceles right triangles, and the downward annular groove and the upward annular groove form a square structure when closed.

[0017] In one embodiment, after the downward annular groove and the upward annular groove are closed, the sealing ring is compressed, and the compression ratio of the sealing ring is 20-30%, preferably 25%.

[0018] In one embodiment, the outer circumference size of the explosion-proof valve plate is the same as the outer circumference size of the orifice plate.

[0019] In one embodiment, the upper surface of the explosion-proof valve plate is provided with a peripheral explosion-proof groove, and the explosion-proof groove is located inside the upward annular groove.

[0020] In one embodiment, a peripheral orifice plate explosion-proof groove is provided at the bottom of the downward groove.

[0021] In one embodiment, the cross-section of the internal gasket is a T-shaped structure, and the internal gasket includes an intermediate cushion layer located between the explosion-proof valve plate and the orifice plate, an upper side wall located outside the explosion-proof valve plate, and a lower side wall located outside the orifice plate.

[0022] In one embodiment, the upper side wall exerts a pressing force on the explosion-proof valve plate, and the lower side wall exerts a pressing force on the orifice plate.

[0023] In one embodiment, the thickness of the intermediate cushion layer is slightly greater than the height of the boss structure.

[0024] In one embodiment, the thickness of the upper side wall is slightly greater than the thickness of the explosion-proof valve plate.

[0025] In one embodiment, the explosion-proof valve plate is connected to the top cover by welding, and the downward groove is connected to the upward groove by welding.

[0026] In one embodiment, the height of the top cover is less than 2.1 mm, preferably less than or equal to 1.7 mm.

[0027] In one embodiment, the height of the explosion-proof valve plate is less than 1.3 mm, preferably less than or equal to 0.6 mm.

[0028] In one embodiment, the height of the orifice plate is less than 0.5 mm, preferably less than or equal to 0.4 mm.

[0029] In one embodiment, the total height of the top cover, explosion-proof valve plate and orifice plate is less than 3.9 mm, preferably less than or equal to 2.7 mm.

[0030] According to another aspect of the present invention, there is provided a battery, comprising the battery cap, the external gasket and the outer shell as described above;

[0031] The external gasket is in direct contact with the side wall of the top cover and the upper and lower surfaces close to the peripheral portion, and is used to connect and seal the battery cap with the outer shell.

[0032] In one embodiment, the explosion-proof valve plate is connected to the top cover by wire welding, and the wire welding is continuous or segmented.

[0033] In one embodiment, the contact between the outer gasket and the upper surface of the top cover does not cover the wire bond.

[0034] In one embodiment, a portion of the outer gasket that contacts the upper surface of the top cover is provided with a circle of protrusions.

[0035] In one embodiment, the wire bond is continuous and the contact of the outer gasket with the upper surface of the top cover covers the wire bond. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to better understand the above and other purposes, features, advantages and functions of the present invention, reference may be made to the preferred embodiments shown in the accompanying drawings. The same reference numerals in the accompanying drawings refer to the same components. It should be understood by those skilled in the art that the accompanying drawings are intended to schematically illustrate the preferred embodiments of the present invention and have no limiting effect on the scope of the present invention, and the components in the drawings are not drawn to scale.

[0037] Figure 1 Schematic diagram of the structure of a battery cap according to a preferred embodiment of the present invention (top view);

[0038] Figure 2 Schematic diagram of the structure of a battery cap according to a preferred embodiment of the present invention (viewed from above);

[0039] Figure 3 An exploded view of a battery cap according to a preferred embodiment of the present invention;

[0040] Figure 4 A cross-sectional view (top view) of a battery cap according to a preferred embodiment of the present invention;

[0041] Figure 5 A cross-sectional view (plan view) of a battery cap according to a preferred embodiment of the present invention;

[0042] Figure 6 for Figure 5 A partial enlarged view of

[0043] Figure 7 Schematic diagram of the structure of an explosion-proof valve plate according to a preferred embodiment of the present invention (viewed from above);

[0044] Figure 8 Schematic diagram of the structure of an explosion-proof valve plate according to a preferred embodiment of the present invention (top view);

[0045] Fig. 9 Schematic diagram of the structure of a hole plate according to a preferred embodiment of the present invention (viewed from above);

[0046] Fig.10 Schematic diagram of the structure of a hole plate according to a preferred embodiment of the present invention (top view);

[0047] Fig.11 A cross-sectional view of a battery cap in the prior art (showing the height);

[0048] Fig.12 FIG. 4 is a cross-sectional view of a battery cap according to a preferred embodiment of the present invention (showing the height).

[0049] Reference numerals:

[0050] 1 Top cover

[0051] 11 Downward annular groove

[0052] 12 wire welding

[0053] 2 explosion-proof valve plate

[0054] 21 Upward groove

[0055] 22 boss structure

[0056] 23 upward annular groove

[0057] 24 explosion-proof slots

[0058] 3-well plate

[0059] 31 Downward groove

[0060] 32-hole plate explosion-proof slot

[0061] 4 Internal gasket

[0062] 41 Middle cushion

[0063] 42 Upper side wall

[0064] 43 lower side wall

[0065] 5 External gasket

[0066] 51 bulge

[0067] 6 Sealing ring

[0068] AHeight of top cover

[0069] B explosion-proof valve plate height

[0070] C hole plate height

[0071] HTotal height of top cover, explosion-proof valve plate and orifice plate DETAILED DESCRIPTION

[0072] Now, with reference to the accompanying drawings, the specific embodiments of the present invention are described in detail. What is described here is only the preferred embodiment of the present invention, and those skilled in the art can think of other ways to implement the present invention on the basis of the preferred embodiment, and the other ways also fall into the scope of the present invention. In some embodiments, in order to avoid confusion with the present invention, some technical features known in the art are not described.

[0073] Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those generally understood by those of ordinary skill in the art. In the event of conflict, the present invention (including definitions) shall prevail. Only exemplary methods and materials are described below, and methods and materials similar or equivalent to those described in the present invention can be used for experiments or tests of the present invention. The materials, methods and examples disclosed in the present invention are only illustrative and are not intended to be limiting. For the narration of the numerical range of the present invention, each intermediate number with the same degree of accuracy is clearly expected. For example, for the range of 6 to 9, in addition to 6 and 9, the numbers 7 and 8 are also considered, and for the range of 6.0 to 7.0, the numbers 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9 and 7.0 are clearly expected.

[0074] Figure 1-Figure 10 The battery cap according to the present invention is shown. First of all, it should be noted that the directional terms and position terms in the present invention should be understood as relative directions and positions, rather than absolute directions and positions. The directional terms and position terms in the present invention can refer to Figure 1-Figure 10 The exemplary structure shown is explained.

[0075] like Fig.11 As shown, in the existing battery cap, in order to achieve effective sealing of the electrolyte under normal working conditions and rapid and effective pressure relief in emergency situations, a higher space margin is usually designed for the explosion-proof valve plate to flip over, thereby increasing the overall height of the cap, and the top cover and the explosion-proof valve plate are sealed by wire welding. If the wire welding is not strong enough, leakage is also likely to occur.

[0076] The present invention provides a battery cap which can partially solve the above-mentioned drawbacks of the existing battery cap structure. Under the conditions of ensuring effective sealing of the electrolyte under normal working conditions and rapid and effective pressure relief in emergency situations, the overall height of the cap can be reduced, thereby increasing the height of the winding core and the amount of electrolyte injection.

[0077] refer to Figure 1-Figure 10 A battery cap according to a preferred embodiment of the present invention comprises the following structure:

[0078] Top cover 1;

[0079] An explosion-proof valve plate 2, wherein the explosion-proof valve plate 2 is disposed below the top cover 1 and is electrically connected to the top cover 1, and the outer circumference of the explosion-proof valve plate 2 is smaller than the outer circumference of the top cover 1;

[0080] An orifice plate 3, wherein the orifice plate 3 is disposed below the explosion-proof valve plate 2, the orifice plate 3 is electrically connected to the explosion-proof valve plate 2 at the center and is separated from the explosion-proof valve plate 2 by a gap at the peripheral position;

[0081] The internal gasket 4 is used to seal the gap between the explosion-proof valve plate 2 and the outer periphery of the orifice plate 3 .

[0082] It should be noted that although Figure 1-Figure 12 The battery caps shown are all cylindrical, but those skilled in the art will understand that the battery cap structure described in the present invention can also be applied to square batteries. For square batteries, it is only necessary to convert the structure in the figure from a circle to a corresponding square. In the conversion process, in order to ensure the technical effect of the present invention, the square structure will be appropriately adjusted. For example, when the internal gasket 4 is converted from a circular ring to a square, its sealing performance must be ensured through structural design. The above conversion and adjustment are routine operations for those skilled in the art, and no creative work is required.

[0083] The outer peripheral size mentioned in the present invention refers to the outer edge size of the component, which corresponds to the diameter of a cylindrical battery and the corresponding side length of a square battery. Fig.11 As shown, in the prior art, the outer circumference of the explosion-proof valve plate is larger than the outer circumference of the top cover, and the outer circumference of the explosion-proof valve plate will cover the outer circumference of the top cover to obtain better sealing, but this also increases the height of the explosion-proof valve plate. Figure 4 As shown, the internal gasket 4 is used to seal the gap between the explosion-proof valve plate 2 and the outer periphery of the orifice plate 3, that is, to ensure that the edges of the explosion-proof valve plate 2 and the orifice plate 3 are sealed.

[0084] In addition, the electrical connection described in the present invention refers to a conductive connection between two components, and needs to have a certain connection strength, such as connection by welding or bonding with a conductive adhesive, etc., which is not limited here.

[0085] The structure in which the orifice plate 3 and the explosion-proof valve plate 2 are electrically connected at the center and separated at the peripheral position with a gap is not specifically limited, as long as the above functions can be met. Fig.11 As shown, the explosion-proof valve plate can adopt the structure of being integrally recessed downward in the prior art.

[0086] In order to achieve a better explosion-proof effect, as a preferred embodiment, Figure 4 and Figure 5As shown, an upward groove 21 with an opening upward is provided at the center of the explosion-proof valve plate 2; a downward groove 31 with an opening downward is provided at the center of the orifice plate 3; the downward groove 31 is electrically connected to the upward groove 21 (i.e., constitutes a current cut-off device CID); the upward groove 21 or the downward groove 31 has a boss structure 22, so that a gap is left between the explosion-proof valve plate 2 and the orifice plate 3 (the gap is used for the gas generated when an abnormality occurs in the battery to enter to open the CID).

[0087] Please refer to Figure 4 , Figure 5 , Figure 7-Figure 10 The boss structure 22 is used to leave a gap between the explosion-proof valve plate 2 and the orifice plate 3, and the gap is used for the gas generated when the battery is abnormal to enter to open the CID. Those skilled in the art can understand that as a preferred embodiment, the boss structure 22 can be formed by the bottom of the upward groove 21, and the boss structure 22 protrudes from the lower surface of the explosion-proof valve plate 2 (refer to Figure 4 , Figure 5 , Figure 7 ); correspondingly, the downward groove 31 is a pit-shaped structure (preferably a cylindrical groove) formed at the center of the orifice plate 3, and the upper surface of the orifice plate 3 is the same plane (reference Fig. 9 , Fig.10 As another preferred embodiment, which is not shown in the figure but can be understood by those skilled in the art, the boss structure can be formed by the top of the downward groove 31, and the boss structure protrudes from the upper surface of the orifice plate 3; correspondingly, the upward groove 21 is a pit-shaped structure (preferably a cylindrical groove) formed at the center of the explosion-proof valve plate 2, and the lower surface of the explosion-proof valve plate 2 is the same plane.

[0088] Please continue to refer to Figure 1 The top cover 1 of the present invention is provided with a vent hole for pressure relief, which is a conventional structure in the art, and the present invention does not specifically limit its structure. Due to the special design of the explosion-proof valve plate 2 structure of the present invention, the explosion-proof valve plate 2 can occupy less space when flipped upward, thereby reducing the height A of the top cover 1.

[0089] In order to ensure a certain sealing between the explosion-proof valve plate 2 and the top cover 1, the two are connected by wire welding 12, and the wire welding 12 surrounds the center of the explosion-proof valve plate 2 and the top cover 1. The wire welding 12 can be continuous or segmented, preferably continuous.

[0090] To achieve better sealing effect, such as Figure 3-Figure 6As shown, as a further preferred embodiment, a sealing ring 6 is provided between the top cover 1 and the explosion-proof valve plate 2, and the sealing ring 6 is made of an elastic material, such as rubber, etc. It is used to further seal the top cover 1 and the explosion-proof valve plate. Specifically, as a preferred embodiment, a downward annular groove 11 is provided on the lower surface of the top cover 1, and an upward annular groove 23 is provided on the upper surface of the explosion-proof valve plate 2. The space formed by closing the downward annular groove 11 and the upward annular groove 23 is used to accommodate the sealing ring 6.

[0091] Please refer to Figure 5 and Figure 6 As a preferred embodiment, the cross-sections of the downward annular groove 11 and the upward annular groove 23 are both isosceles triangles or semicircles, and the downward annular groove 11 and the upward annular groove 23 are rhombus structures or circular structures after being closed. As a further preferred embodiment, the cross-sections of the downward annular groove 11 and the upward annular groove 23 are both isosceles right triangles, and the downward annular groove 11 and the upward annular groove 23 are square structures after being closed. In order to achieve a better sealing effect, as a preferred embodiment, after the downward annular groove 11 and the upward annular groove 23 are closed, the sealing ring 6 is compressed, and the compression ratio of the sealing ring 6 is 20-30%, preferably 25%. Wherein, the compression ratio is calculated by the following formula: sealing ring compression ratio = (original diameter of the sealing ring - diameter after compression) ÷ original diameter of the sealing ring × 100%, where the diameter is the diameter of the cross section of the sealing ring. For example, if the original diameter of the sealing ring is 0.2 mm and the diameter after compression is 0.15 mm, the sealing ring compression ratio is 25%.

[0092] As a preferred embodiment, please refer to Figure 4 and Figure 5 The outer circumference of the explosion-proof valve plate 2 is the same as the outer circumference of the orifice plate 3. The inner gasket 4 may be a conventional annular gasket structure. Preferably, the cross section of the inner gasket 4 is a T-shaped structure. Figure 5As shown, the internal gasket 4 includes an intermediate cushion layer 41 located between the explosion-proof valve plate 2 and the orifice plate 3, an upper side wall 42 located outside the explosion-proof valve plate 2, and a lower side wall 43 located outside the orifice plate 3. That is, the upper side wall 42 is used to accommodate the explosion-proof valve plate 2, and the lower side wall 43 is used to accommodate the orifice plate 3. As a further preferred embodiment, the upper side wall 42 has an extrusion force on the explosion-proof valve plate 2 (the inner diameter of the upper side wall 42 is slightly smaller than the diameter of the explosion-proof valve plate 2), and the lower side wall 43 has an extrusion force on the orifice plate 3 (the inner diameter of the lower side wall 43 is slightly smaller than the diameter of the orifice plate 3), so as to effectively fix the explosion-proof valve plate 2 and the orifice plate 3 and improve their sealing. Preferably, the thickness of the intermediate cushion layer 41 is slightly greater than the height of the boss structure 22, that is, the explosion-proof valve plate 2 and the orifice plate 3 will have a certain extrusion force on the intermediate cushion layer 41, so as to improve the sealing of the periphery between the explosion-proof valve plate 2 and the orifice plate 3. And more preferably, the thickness of the upper side wall 42 is slightly greater than the thickness of the explosion-proof valve plate 2, that is, the upper side wall 42 will exert a certain squeezing force on the top cover 1 to improve the sealing between the explosion-proof valve plate 2 and the top cover 1. In addition, such a design, while ensuring the above-mentioned sealing performance, makes the structure composed of the explosion-proof valve plate 2, the orifice plate 3 and the internal gasket 4 more compact and reduces the space occupied.

[0093] As a preferred embodiment, the downward groove 31 is connected to the upward groove 21 by welding, such as spot welding, to achieve a certain connection strength and good conductivity. The connection strength needs to be sufficient to separate the two when a certain amount of gas is generated during abnormal use of the battery, that is, the CID is turned on to disconnect the battery.

[0094] In addition, in order to better realize the overturning of the explosion-proof valve plate 2 under a certain air pressure, as a preferred embodiment, Figure 4 , Figure 5 , Figure 8 As shown, a circle of explosion-proof grooves 24 are provided on the upper surface of the explosion-proof valve plate 2, and the explosion-proof grooves 24 are located inside the upward annular grooves 23. The depth and other dimensions of the explosion-proof grooves 24 need to meet the requirements that when a certain amount of gas is generated due to abnormal use of the battery, the explosion-proof valve plate 2 can be turned over, or even the explosion-proof grooves 24 can be cracked to discharge the gas, so as to prevent the battery from exploding.

[0095] As a further preferred embodiment, Fig. 9 As shown, a peripheral hole plate explosion-proof groove 32 is provided at the bottom of the downward groove 31 . When a certain amount of gas is generated due to abnormal use of the battery, the downward groove 31 can be depressed downward to better separate the downward groove 31 from the upward groove 21 .

[0096] Through the above structural design of the present invention, the height of the battery cap can be reduced as much as possible on the basis of meeting certain sealing performance and explosion-proof performance. Fig.11 , Fig.12 As shown in the table below, compared with the prior art, the height of the top cover 1 of the present invention is less than 2.1 mm, preferably less than or equal to 1.7 mm; the height of the explosion-proof valve plate 2 is less than 1.3 mm, preferably less than or equal to 0.6 mm; the height of the orifice plate 3 is less than 0.5 mm, preferably less than or equal to 0.4 mm. Furthermore, the total height of the top cover 1, the explosion-proof valve plate 2 and the orifice plate 3 is less than 3.9 mm, preferably less than or equal to 2.7 mm.

[0097] Existing technology / mm The present invention / mm Reduction / mm Top cover height (A) 2.10 1.70 0.40 Explosion-proof valve plate height (B) 1.30 0.60 0.70 Orifice plate height (C) 0.50 0.40 0.10 Overall height (H) 3.90 2.70 1.20

[0098] As can be seen from the table above, the cap height of the present invention can be reduced by 31% compared to the prior art, and the height of the winding core and the amount of electrolyte injection can be effectively increased while the battery height remains unchanged, thereby increasing the overall capacity of the battery.

[0099] Another aspect of the present invention provides a battery, comprising the battery cap, the external gasket 5 and the outer shell of the present invention as described above;

[0100] Please continue to refer to Figure 1-Figure 5 The external gasket 5 is in direct contact with the side wall of the top cover 1 and the upper and lower surfaces close to the peripheral portion, and is used to connect and seal the battery cap to the outer shell.

[0101] As an implementation method, Figure 1 and Figure 4 As shown, the explosion-proof valve plate 2 is connected to the top cover 1 by wire welding 12, and the wire welding 12 is continuous or segmented.

[0102] In order to achieve better sealing effect, such as Figure 1 and Figure 4 As shown, as a preferred embodiment, the contact between the external gasket 5 and the upper surface of the top cover 1 does not cover the wire weld 12. The wire weld 12 and the external gasket 5 work together to achieve a better sealing effect.

[0103] like Figure 4 As shown, as a further preferred embodiment, the portion where the external gasket 5 contacts the upper surface of the top cover 1 is provided with a circle of protrusions 51, and when the external gasket 5 contacts the upper surface of the top cover 1, the protrusions 51 can achieve a better sealing effect.

[0104] As another embodiment, the wire weld 12 is continuous, and the contact between the external gasket (5) and the upper surface of the top cover 1 covers the wire weld 12. Since the wire weld 12 is a continuous protrusion, when the external gasket 5 contacts the upper surface of the top cover 1 and covers the wire weld 12, the protrusion can also achieve a better sealing effect.

[0105] The present invention does not impose any specific limitation on the material of the inner gasket 4 and the outer gasket 5 as long as they can achieve the sealing effect, such as elastic material rubber.

[0106] In addition, as another aspect of the present invention, a method for assembling a battery cap is provided, comprising the following steps:

[0107] Step 1, install the sealing ring 6 in the downward annular groove 11 of the top cover 1, and buckle the upward annular groove 23 of the explosion-proof valve plate 2 on the sealing ring 6;

[0108] Step 2, pressing the top cover 1 and the explosion-proof valve plate 2 together and welding them by wire welding;

[0109] Step 3, buckle the upper side of the internal gasket 4 onto the explosion-proof valve plate 2, buckle the orifice plate 3 onto the lower side of the internal gasket 4, and connect the downward groove 31 of the orifice plate 3 with the upward groove 21 of the explosion-proof valve plate 2 by welding.

[0110] The above description of various embodiments of the present invention is provided to one of ordinary skill in the relevant art for the purpose of description. It is not intended that the present invention be exclusive or limited to a single disclosed embodiment. As above, a person of ordinary skill in the field of the above teachings will understand the various substitutions and variations of the present invention. Therefore, although some alternative embodiments are specifically described, a person of ordinary skill in the art will understand or relatively easily develop other embodiments. The present invention is intended to include all substitutions, modifications and variations of the present invention described herein, as well as other embodiments that fall within the spirit and scope of the present invention described above.

Claims

1. A battery cap, characterized in that: include: Top cover (1); an explosion-proof valve plate (2), the explosion-proof valve plate (2) being arranged below the top cover (1) and being electrically connected to the top cover (1), the outer circumference of the explosion-proof valve plate (2) being smaller than the outer circumference of the top cover (1); An orifice plate (3), the orifice plate (3) being arranged below the explosion-proof valve plate (2), the orifice plate (3) being electrically connected to the explosion-proof valve plate (2) at a central position and being separated from the explosion-proof valve plate (2) by a gap at a peripheral position; An internal gasket (4), the internal gasket (4) is used to seal the gap between the explosion-proof valve plate (2) and the outer periphery of the orifice plate (3).

2. The battery cap according to claim 1, characterized in that: An upward groove (21) is provided at the center of the explosion-proof valve (2), and a downward groove (31) is provided at the center of the orifice plate (3); the downward groove (31) is electrically connected to the upward groove (21); and the upward groove (21) or the downward groove (31) has a boss structure (22).

3. The battery cap according to claim 2, characterized in that: The upward groove (21) has a boss structure (22), and the boss structure (22) protrudes from the lower surface of the explosion-proof valve plate (2); the downward groove (31) is a pit-shaped structure formed at the center position of the orifice plate (3).

4. The battery cap according to claim 2, characterized in that: The downward groove (31) has a boss structure, and the boss structure protrudes from the upper surface of the orifice plate (3); the upward groove (21) is a pit-shaped structure formed at the center position of the explosion-proof valve plate (2).

5. The battery cap according to claim 1, characterized in that: A sealing ring (6) is provided between the top cover (1) and the explosion-proof valve plate (2), and the sealing ring (6) is made of an elastic material.

6. The battery cap according to claim 5, characterized in that: The lower surface of the top cover (1) is provided with a downward annular groove (11), and the upper surface of the explosion-proof valve plate (2) is provided with an upward annular groove (23). The space formed by closing the downward annular groove (11) and the upward annular groove (23) is used to accommodate the sealing ring (6).

7. The battery cap according to claim 6, characterized in that: The cross-sections of the downward annular groove (11) and the upward annular groove (23) are both isosceles triangles or semicircles, and the downward annular groove (11) and the upward annular groove (23) are in a diamond structure or a circular structure when closed; preferably, the cross-sections of the downward annular groove (11) and the upward annular groove (23) are both isosceles right triangles, and the downward annular groove (11) and the upward annular groove (23) are in a square structure when closed.

8. The battery cap according to claim 7, characterized in that: After the downward annular groove (11) and the upward annular groove (23) are closed, the sealing ring (6) is compressed, and the compression ratio of the sealing ring (6) is 20-30%, preferably 25%.

9. The battery cap according to claim 1, characterized in that: The outer circumference size of the explosion-proof valve plate (2) is the same as the outer circumference size of the orifice plate (3).

10. The battery cap according to claim 1, characterized in that: The upper surface of the explosion-proof valve plate (2) is provided with a peripheral explosion-proof groove (24), and the explosion-proof groove (24) is located inside the upward annular groove (23).

11. The battery cap according to claim 1, characterized in that: A peripheral orifice plate explosion-proof groove (32) is provided at the bottom of the downward groove (31).

12. The battery cap according to claim 1, characterized in that: The cross section of the internal gasket (4) is a T-shaped structure. The internal gasket (4) comprises an intermediate gasket (41) located between the explosion-proof valve plate (2) and the orifice plate (3), an upper side wall (42) located outside the explosion-proof valve plate (2), and a lower side wall (43) located outside the orifice plate (3).

13. The battery cap according to claim 12, characterized in that: The upper side wall (42) exerts a pressing force on the explosion-proof valve plate (2), and the lower side wall (43) exerts a pressing force on the orifice plate (3).

14. The battery cap according to claim 12, characterized in that: The thickness of the intermediate cushion layer (41) is slightly greater than the height of the boss structure (22).

15. The battery cap according to claim 12, characterized in that: The thickness of the upper side wall (42) is slightly greater than the thickness of the explosion-proof valve plate (2).

16. The battery cap according to claim 1, characterized in that: The explosion-proof valve plate (2) is connected to the top cover (1) by welding, and the downward groove (31) is connected to the upward groove (21) by welding.

17. The battery cap according to claim 1, characterized in that: The height of the top cover (1) is less than 2.1 mm, preferably less than or equal to 1.7 mm.

18. The battery cap according to claim 1, characterized in that: The height of the explosion-proof valve plate (2) is less than 1.3 mm, preferably less than or equal to 0.6 mm.

19. The battery cap according to claim 1, characterized in that: The height of the orifice plate (3) is less than 0.5 mm, preferably less than or equal to 0.4 mm.

20. The battery cap according to claim 1, characterized in that: The total height of the top cover (1), the explosion-proof valve plate (2) and the orifice plate (3) is less than 3.9 mm, preferably less than or equal to 2.7 mm.

21. A battery, characterized in that: A battery cap, an external gasket (5) and a housing according to any one of claims 1 to 20; The external gasket (5) is in direct contact with the side wall of the top cover (1) and the upper and lower surfaces close to the peripheral portion, and is used to connect and seal the battery cap with the outer shell.

22. The battery cap according to claim 21, characterized in that: The explosion-proof valve plate (2) is connected to the top cover (1) via wire welding (12), and the wire welding (12) is continuous or segmented.

23. The battery according to claim 22, characterized in that The contact between the outer gasket (5) and the upper surface of the top cover (1) does not cover the wire weld (12).

24. The battery according to claim 23, characterized in that The portion of the external gasket (5) that contacts the upper surface of the top cover (1) is provided with a circle of protrusions (51).

25. The battery according to claim 22, characterized in that The wire weld (12) is continuous, and the contact between the external gasket (5) and the upper surface of the top cover (1) covers the wire weld (12).

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