Busbar with power-off pressure relief function, battery cover and battery

Abstract

This invention relates to the field of battery technology, and provides a busbar with power-off and pressure-relief function, a battery cap, and a battery. The busbar includes a power-off structure, a pressure-relief structure, and a connecting section. One end of the connecting section is connected to the power-off structure; the other end of the connecting section is connected to the pressure-relief structure. The power-off structure, the pressure-relief structure, and the connecting section are integrally formed components. A first cutout structure is provided between the power-off structure and the connecting section; a second cutout structure is provided on the surface of the pressure-relief structure. The first and second cutout structures are used to reduce the thickness at corresponding locations. This busbar and battery with power-off and pressure-relief function can ensure reliable disconnection between the pressure-relief structure and the power-off structure when the internal pressure of the battery abnormally increases, while also simplifying the manufacturing process.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a busbar with power-off and pressure relief function, a battery cap, and a battery. Background Technology

[0002] The battery cap is installed at the positive terminal of the battery, serving as the positive conductive terminal and sealing the battery. In addition, the battery cap also needs to have the functions of power cut-off and pressure relief when the internal pressure of the battery rises abnormally.

[0003] The current solution involves spaced power-off structures (CID) and pressure-relief structures (VENT) along the length of the battery. When the battery is operating normally, the power-off structure is connected to the battery cell, while the pressure-relief structure has a concave center that contacts the power-off structure and an edge that contacts the top cap, thus transferring current from the battery cell to the top cap. When the internal pressure of the battery rises abnormally, the concave part of the pressure-relief structure flips into a convex part under the influence of the increased pressure, thereby disconnecting from the power-off structure and disconnecting the power. If the internal pressure of the battery rises further, the pressure-relief structure will rupture to release the pressure in the battery.

[0004] To prevent the power-off structure and the pressure relief structure from disconnecting when the battery is working normally, the recessed parts of the power-off structure and the pressure relief structure are often connected by welding. However, due to the high strength of the welded joint, it is difficult to completely separate the pressure relief structure from the power-off structure when it is flipped, thus making it impossible to disconnect the power. Moreover, the welding quality is easily affected by the external environment and welding equipment, which can cause unexpected changes in the Vent flipping pressure, which is not conducive to the quality control of the battery cap.

[0005] Meanwhile, welding operations are performed in the gap between the power-off structure and the pressure relief structure, which is difficult to process and will negatively affect the control of working time and cost. Summary of the Invention

[0006] The purpose of this invention is to solve the problem that existing battery caps with welded power-off and pressure-relief structures are prone to incomplete power-off due to excessive connection strength at the weld points. This invention provides a busbar, battery cap, and battery with power-off and pressure-relief functions.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A busbar with power-off and pressure relief function includes a power-off structure and a pressure relief structure; characterized in that it further includes a connecting section;

[0009] One end of the connecting section is connected to the power-off structure; the other end of the connecting section is connected to the pressure relief structure; the power-off structure, the pressure relief structure, and the connecting section are integrally formed components;

[0010] A first cutout structure is provided between the power-off structure and the connecting section; a second cutout structure is provided on the surface of the pressure relief structure; the first cutout structure and the second cutout structure are respectively used to reduce the thickness at the corresponding positions.

[0011] The specific shape of the connecting section is designed based on the performance of the bending machine, the bending characteristics of the material used in the connecting section, and the installation dimensions of the manifold. It can be U-shaped or straight. One or more connecting sections can be set, but it should be ensured that the manifold can be unfolded into a plane. The specific cross-sectional dimensions of the connecting section depend on the flow requirements.

[0012] The first cut structure can be of various shapes, such as continuous straight lines, discontinuous straight lines, continuous curves, or discontinuous curves, as long as it can induce the disconnection of the power-off structure and the connecting section when the internal pressure of the battery rises to the specified pressure; the second cut structure can be of various shapes, such as circular or square, as long as it can induce the pressure relief structure to rupture when the internal pressure of the battery rises to the specified pressure; the residual thickness of the first cut structure is determined according to the required cutting pressure of the power-off structure; the residual thickness of the second cut structure is determined according to the required cutting pressure of the pressure relief structure.

[0013] The installation method of the busbar is similar to that of the existing battery cap, that is, the power-off structure is electrically connected to the cell tabs of the battery cell, and the pressure relief structure is electrically connected to the top cap of the battery. Attention should also be paid to the seal between the busbar and the inner wall of the battery.

[0014] This solution integrates the power-off structure and the pressure relief structure into a single busbar. Corresponding cut structures 1 and 2 are installed at the points where breakage is required. The cutting pressure of the power-off and pressure relief structures is directly determined by the component dimensions. Compared to welded connections that require excessive strength and are easily affected by external factors, the cutting pressure of this solution is highly controllable, ensuring reliable breakage of the power-off and pressure relief structures after reaching the designed cutting pressure. Specifically, when the battery internal pressure abnormally rises to the designed breakage pressure of cut structure 1, the power-off structure breaks at one cut structure and tilts up under the pressure of the battery internal pressure, thus disconnecting the cell from the top cap and achieving battery power-off. If the battery internal pressure further rises to the designed breakage pressure of cut structure 2, the pressure relief structure cracks at cut structure 2, thereby compromising the seal of the battery cap and achieving battery pressure relief.

[0015] Both cut structure one and cut structure two have residual thickness at corresponding positions to prevent damage to the battery casing seal when the battery is working normally.

[0016] Furthermore, by integrating the power-off structure and the pressure relief structure into a single busbar, this solution reduces the number of parts and eliminates the welding process, thereby improving production efficiency, reducing manufacturing time and costs, and making quality control easier.

[0017] Meanwhile, compared to existing technologies that use welding connections, the current carrying capacity of the connection section between the power-off structure and the pressure relief structure in this solution is determined by the external dimensions of the connection section. Compared to welding connections that are easily affected by external factors, this solution makes it easier to design a connection section of appropriate size according to the current carrying requirements between the power-off structure and the pressure relief structure.

[0018] As a preferred embodiment of the present invention, the opening orientation of the first cut structure is opposite to that of the second cut structure.

[0019] If the first cutout faces the battery cell, then the second cutout faces the top cap.

[0020] After the manifold of this solution is unfolded, cut structure one and cut structure two are located on the same side of the manifold, which can facilitate the one-time molding of cut structure one and cut structure two, reducing processes and time.

[0021] As a preferred embodiment of the present invention, the busbar further includes an insulating washer; the insulating washer is disposed between the pressure relief structure and the power-off structure; the insulating washer is provided with a third cutout structure at the corresponding position of the first cutout structure.

[0022] Insulating gaskets should be made of insulating material and be able to adapt to the working environment inside the battery, such as PET and PVC.

[0023] The third cut can be through the insulating washer or not, as long as the thickness of the insulating washer at the third cut is less than the thickness of other parts.

[0024] This design can form a support between the pressure relief structure and the power-off structure to prevent the busbar from deforming. At the same time, the third cut structure can also induce the insulating gasket to cut off from the same position as the power-off structure, thereby avoiding the insulating gasket from hindering the disconnection and lifting of the power-off structure. The insulating gasket can also prevent the lifted part from contacting the pressure relief structure after the power-off structure is disconnected from the first cut structure and lifted under the action of the battery internal pressure, thereby ensuring the reliability of the power-off.

[0025] As a preferred embodiment of the present invention, the width of the third cut structure is greater than the width of the first cut structure.

[0026] This solution can prevent interference between the edge of the power-off structure near the first cut structure and the edge of the third cut structure when the power-off structure breaks off from the first cut structure and tilts up.

[0027] As a preferred embodiment of the present invention, the projection of the first cutout structure on the insulating washer covers the third cutout structure along the length direction.

[0028] This solution involves controlling the length of the third cut structure to be less than the length of the first cut structure, and offsetting the edges of the first and third cut structures to increase the length of the leakage path, thereby preventing potential leakage before the power-off structure is cut off.

[0029] As a preferred embodiment of the present invention, the thickness of the region corresponding to the insulating washer and the power-off structure is less than the thickness of other regions on the insulating washer.

[0030] The specific thickness of the insulating gasket corresponding to the power-off structure is designed according to the breaking pressure required by the power-off structure; the thickness of the insulating gasket can be reduced by setting grooves or hollow cavities.

[0031] This solution reduces the thickness of the insulating gasket at the location corresponding to the power-off structure, thereby reducing the pressure that the power-off structure needs to overcome when it tilts up, making the tilting of the power-off structure smoother, and thus ensuring the reliability of its power-off function.

[0032] As a preferred embodiment of the present invention, the insulating washer is provided with a groove structure on the side facing the pressure relief structure; the space between the groove structure and the insulating washer forms an air groove.

[0033] When the internal pressure of the battery rises abnormally, causing the power-off structure to break after the first cut-out structure is disconnected, the groove structure of this solution can be used to collect the gas that has rushed in from the first cut-out structure, thereby providing sufficient pressure to break the second cut-out structure.

[0034] The groove structure of this design can also reduce the thickness of the insulating gasket at the corresponding position, making it easier for the insulating gasket to break off with the power-off structure.

[0035] As a preferred embodiment of the present invention, the insulating washer and the power-off structure are bonded together.

[0036] Adhesive bonding can be achieved using glue or tape, but the appropriate type should be selected based on the battery's internal working environment, such as its resistance to electrolyte corrosion.

[0037] This solution involves bonding the power-off structure and the insulating gasket together. This prevents the power-off structure from being cut off from the cut structure and then falling back down and overlapping the edge of the cut structure when the battery casing is subjected to impact or vibration. This makes the power-off function of this solution more reliable.

[0038] As a preferred embodiment of the present invention, the pressure relief structure is provided with a protruding structure whose shape and position correspond to the power-off structure; the protruding structure protrudes in a direction away from the power-off structure.

[0039] The specific height of the protrusion depends on the specific fracture condition of the power-off structure, and is calculated to prevent interference with the pressure relief structure when the power-off structure warps after fracture.

[0040] This solution creates additional burst space between the power-off structure and the pressure relief structure without increasing the height of the connecting section, preventing the power-off structure from contacting the pressure relief structure when it breaks and warps up. This allows the height of the connecting section to be relatively reduced, thereby reducing the thickness of the outer sealing ring and making the battery cap structure of this solution more compact.

[0041] Meanwhile, the space between the raised structure and the insulating gasket can form a gas groove for accumulating gas. When the first cut structure breaks, the gas inside the battery passes through the third cut structure and gathers in the gas groove, thereby driving the second cut structure to break with gas pressure. In other words, the raised structure of this solution is also beneficial to ensure that the second cut structure can be reliably cut off when the internal pressure of the battery rises abnormally.

[0042] As a preferred embodiment of the present invention, the second cutout structure is C-shaped on the pressure relief structure; the area of ​​the circular region enclosed by the second cutout structure is larger than the area of ​​the power-off structure.

[0043] The second cut structure in this design encloses a circular area on the pressure relief structure, while retaining a section of the arc without a groove. This ensures that when the internal pressure of the battery rises to a specified pressure and causes the pressure relief structure to break along the second cut structure, the circular portion enclosed by the second cut structure will lift up from the arc section without a groove, forming a circular notch for pressure relief. Furthermore, the area of ​​the circular notch is larger than the area of ​​the power-off structure, preventing the lifted power-off structure from blocking the pressure relief notch, thus ensuring the stability of the venting and pressure relief effect.

[0044] A battery cover with power-off and pressure relief function includes a top cover and a busbar of the present invention; the top cover is connected to the side of the pressure relief structure opposite to the power-off structure.

[0045] The battery cap in this design uses a busbar with a power-off and pressure relief function, which can reliably and promptly cut off power and relieve pressure when the internal pressure of the battery rises abnormally.

[0046] A battery with power-off and pressure relief function includes a battery casing; one end of the battery casing is open; and the busbar of the present invention is installed at the opening of the battery casing.

[0047] This solution utilizes a busbar with a power-off and pressure-relief function, which enables timely and reliable power-off and pressure relief when the battery internal pressure rises abnormally.

[0048] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0049] 1. By integrating the power-off structure and the pressure relief structure into a single component, and setting corresponding cutting structures one and two at the points where breakage is required, the cutting pressure of the power-off structure and the pressure relief structure in this solution is directly determined by the component size. Compared with the use of welded connections that are too strong and easily affected by external factors, the cutting pressure of this solution is highly controllable, thus enabling the power-off structure and the pressure relief structure in this solution to reliably cut off after reaching the designed cutting pressure.

[0050] 2. By integrating the power-off structure and the pressure relief structure into a single component, this solution reduces the number of parts and eliminates the welding process, thereby improving production efficiency, reducing manufacturing time and costs, and making quality control easier.

[0051] 3. Compared with the existing technology that uses welding connections, the current carrying capacity of the connection section between the power-off structure and the pressure relief structure in this solution is determined by the external dimensions of the connection section. Compared with the welding connection that is easily affected by external factors, this solution makes it easier to design a connection section of appropriate size according to the current carrying requirements between the power-off structure and the pressure relief structure.

[0052] 4. The battery cover in this solution uses a busbar with power-off and pressure relief function, which can promptly and reliably cut off power and relieve pressure when the internal pressure of the battery rises abnormally.

[0053] 5. The battery in this solution uses a busbar with power-off and pressure relief function, which can reliably and promptly cut off power and relieve pressure when the internal pressure of the battery rises abnormally. Attached Figure Description

[0054] Figure 1 This is a front-view cross-sectional diagram of a combiner plate with power-off and pressure relief function installed in battery mode according to the present invention;

[0055] Figure 2 This is a magnified cross-sectional diagram of the busbar;

[0056] Figure 3 This is a three-dimensional structural diagram of the busbar self-power-off structure viewed from above;

[0057] Figure 4 This is a front view schematic diagram of the self-relief structure of the busbar;

[0058] Figure 5 This is a front view diagram of the busbar self-disconnection component.

[0059] Figure 6 This is a front view schematic diagram of the insulating washer as seen from its groove structure;

[0060] Icons: 1-Top cap; 2-Bucket plate; 3-Pressure relief port; 4-Outer sealing ring; 5-Battery casing; 6-Battery cell;

[0061] 21-Power-off structure; 22-Pressure relief structure; 23-Connecting section; 24-Insulating washer;

[0062] 211 - Cut structure one; 221 - Cut structure two; 222 - Protrusion structure; 241 - Cut structure three; 242 - Groove structure. Detailed Implementation

[0063] The present invention will now be described in detail with reference to the accompanying drawings.

[0064] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0065] Example 1

[0066] like Figures 1-6 As shown, the manifold 2 with power-off and pressure relief function used in this invention includes a pressure relief structure 22 and a power-off structure 21. Both the pressure relief structure 22 and the power-off structure 21 are disc-shaped and are connected as one piece from the side by a connecting section 23. The manifold 2 is an integrally formed component, specifically, it is formed by bending and stamping.

[0067] A first cutout structure 211 is provided at the connection between the power-off structure 21 and the connecting section 23, and a second cutout structure 221 is also provided on the pressure relief structure 22. In this embodiment, the second cutout structure 221 is C-shaped, and as shown... Figure 4 and Figure 5 As shown, the diameter of its arc segment is D2, which is larger than the diameter D1 of the power-off structure 21, so that the area enclosed by it is larger than the area of ​​the power-off structure 21, thereby completely preventing the gap formed after the fracture structure 221 breaks from being blocked by the raised power-off structure 21.

[0068] An insulating washer 24 is sandwiched between the pressure relief structure 22 and the power-off structure 21. The insulating washer 24 has a groove structure 242 whose size and position correspond to those of the power-off structure 21, forming an air groove between the insulating washer 24 and the pressure relief structure 22, and reducing the thickness of the portion of the insulating washer 24 corresponding to the power-off structure 21. A third cut structure 241 is also provided on the insulating washer 24 at the position corresponding to the first cut structure 211, and... Figure 2 , Figure 5 and Figure 6 As shown, the width W2 of the third cut structure 241 is greater than the width W1 of the first cut structure 211. The length of the third cut structure 241 is L2, and the length of the first cut structure 211 is L1, where L1 > L2. Furthermore, both ends of the third cut structure 241 along its length direction are 1 mm shorter than both ends of the first cut structure 211. In this embodiment, the third cut structure 241 is a through groove to facilitate processing.

[0069] When installed in the battery, the busbar 2 is placed at the opening of the battery casing 5 and electrically connected from one end of the power-off structure 21 to the cell tab of the battery cell 6, and from one end of the pressure relief structure 22 to the top cap 1, thereby achieving electrical connection between the battery cell 6 and the top cap 1 when the battery is working normally, ensuring the normal operation of the battery; an outer sealing ring 4 is also provided between the busbar 2 and the inner wall at the opening of the battery casing 5 to form a seal on the battery casing 5.

[0070] When the internal pressure of the battery abnormally rises to the design fracture pressure of the first cut structure 211, the power-off structure 21 breaks off from the first cut structure 211 and tilts up under the action of the internal pressure of the battery, thereby disconnecting the connection between the cell and the top cap 1 and realizing the power-off of the battery; at the same time, the insulating gasket 24 is also driven by the tilted power-off structure 21, breaking off from the end where the third cut structure 241 is located and tilting up; if the internal pressure of the battery rises further, the gas in the battery will accumulate between the insulating gasket 24 and the pressure relief structure 22 until it reaches the design fracture pressure of the second cut structure 221, causing the pressure relief structure 22 to crack from the second cut structure 221, thereby destroying the battery's seal and realizing the battery pressure relief.

[0071] Specifically, in this embodiment, the middle part of the top cap 1 protrudes upward and is provided with a pressure relief port 3; the outer sealing ring 4 is roughly annular and has a groove on its inner side. The height of the groove corresponds to the thickness of the combination of the top cap 1 and the busbar 2. The outer edges of the top cap 1 and the busbar 2 are engaged in the groove on the inner side of the outer sealing ring 4, so that when the busbar 2 with power-off pressure relief function in this embodiment is installed on the battery housing 5, a seal can be formed on the battery housing 5.

[0072] It should be noted that, unless otherwise specified, the height direction refers to the height direction of the battery casing 5; above, such as above the power-off structure 21 or above the pressure relief structure 22, refers to the direction along the height of the battery casing 5 and pointing towards the opening of the battery casing 5.

[0073] Example 2

[0074] Based on Example 1, the contact surfaces of the insulating gasket 24 and the power-off structure 21 are coated with adhesive to bond the insulating gasket 24 and the power-off structure 21 together.

[0075] This embodiment enables the power-off structure 21 to connect more reliably with the insulating washer 24, preventing the power-off structure 21 from tilting up and then falling back down due to external impacts or vibrations.

[0076] Example 3

[0077] like Figures 1-4As shown, based on embodiments 1 and 2, the first cut structure 211 is provided on the lower surface of the U-shaped connection end; the second cut structure 221 is provided on the upper surface of the pressure relief structure 22.

[0078] In this embodiment, before the bending process, the first cut structure 211 and the second cut structure 221 of the busbar 2 are located on the same side of the busbar 2 plate, so that they can be processed in one go, simplifying the production process and shortening the working time.

[0079] Example 4

[0080] like Figures 1-4 As shown, based on embodiments 1 to 3, a circular protrusion 222 is provided on the pressure relief structure 22 at the corresponding position of the power-off structure 21, and the radius of the protrusion 222 is larger than the radius of the power-off structure 21.

[0081] This embodiment can create an additional burst space between the power-off structure 21 and the pressure relief structure 22 without increasing the height of the connecting section 23, thereby making the structure of the busbar 2 more compact; and the space between the protruding structure 222 and the insulating gasket 24 can form a gas collecting groove for accumulating gas. When the first cut structure 211 breaks, the gas in the battery passes through the third cut structure 241 and collects in the gas collecting groove, thereby driving the second cut structure 221 to break with gas pressure. That is, the protruding structure 222 in this embodiment is also beneficial to ensure that the second cut structure 221 is reliably cut off when the internal pressure of the battery rises abnormally.

[0082] Example 5

[0083] The battery cap with power-off and pressure relief function used in this invention includes a top cap 1 and any one of the busbars 2 in embodiments 1 to 4; wherein the top cap 1 is connected to the side of the pressure relief structure 22 of the busbar 2 away from the power-off structure 21, and a pressure relief port 3 is provided on the top cap 1.

[0084] Example 6

[0085] like Figure 1 As shown, the battery with power-off and pressure relief function used in this invention includes a battery casing 5 and a busbar 2. One end of the battery casing 5 is open, and the busbar 2 is disposed at the opening of the battery casing 5. An outer sealing ring 4 is provided between the inner wall of the opening of the battery casing 5 and the busbar 2 to seal the battery casing 5. The power-off structure 21 of the busbar 2 is electrically connected to the cell tab of the battery cell 6 inside the battery casing 5. The pressure relief structure 22 of the busbar 2 is connected to a top cap 1 on the side opposite to the power-off structure 21.

[0086] The busbar 2 can be any one of the busbars 2 in Examples 1 to 4.

[0087] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A busbar (2) with power-off and pressure relief function, comprising a power-off structure (21) and a pressure relief structure (22); characterized in that, It also includes a connection segment (23); One end of the connecting section (23) is connected to the power-off structure (21); the other end of the connecting section (23) is connected to the pressure relief structure (22); the connecting section (23) connects the power-off structure (21) and the pressure relief structure (22) from the side into one piece, and the power-off structure (21), the pressure relief structure (22) and the connecting section (23) are an integrally formed component; A first cut structure (211) is provided between the power-off structure (21) and the connecting section (23); a second cut structure (221) is provided on the surface of the pressure relief structure (22); the first cut structure (211) and the second cut structure (221) are respectively used to reduce the thickness at the corresponding positions; the power-off structure (21) can be disconnected from the first cut structure (211) and tilted up under the action of the internal pressure of the battery; the pressure relief structure (22) can be cracked from the second cut structure (221); The busbar (2) also includes an insulating washer (24); the insulating washer (24) is disposed between the pressure relief structure (22) and the power-off structure (21); the insulating washer (24) has a cut structure three (241) at the corresponding position of the cut structure one (211).

2. The busbar (2) with power-off and pressure relief function according to claim 1, characterized in that, The opening orientation of the first cut structure (211) is opposite to that of the second cut structure (221).

3. The busbar (2) with power-off and pressure relief function according to claim 1, characterized in that, The width of the third cut structure (241) is greater than the width of the first cut structure (211).

4. The busbar (2) with power-off and pressure relief function according to claim 1, characterized in that, The projection of the first cut structure (211) on the insulating washer (24) along the length direction covers the third cut structure (241).

5. A busbar (2) with power-off and pressure relief function according to claim 1, characterized in that, The thickness of the area corresponding to the insulating gasket (24) and the power-off structure (21) is less than the thickness of other areas on the insulating gasket (24).

6. The busbar (2) with power-off and pressure relief function according to claim 1, characterized in that, The insulating washer (24) has a groove structure (242) on the side facing the pressure relief structure (22); the space between the groove structure (242) and the insulating washer (24) forms an air groove.

7. A busbar (2) with power-off and pressure relief function according to claim 1, characterized in that, The insulating gasket (24) and the power-off structure (21) are bonded together.

8. A busbar (2) with power-off and pressure relief function according to any one of claims 1 to 7, characterized in that, The pressure relief structure (22) is provided with a protruding structure (222) whose shape and position correspond to the power-off structure (21); the protruding structure (222) protrudes in a direction away from the power-off structure (21).

9. A busbar (2) with power-off and pressure relief function according to any one of claims 1 to 7, characterized in that, The second cut structure (221) is C-shaped on the pressure relief structure (22); the area of ​​the circular region enclosed by the second cut structure (221) is larger than the area of ​​the power-off structure (21).

10. A battery cap with power-off and pressure relief function, comprising a top cap (1), characterized in that, It also includes a busbar (2) as described in any one of claims 1 to 9; the top cap (1) is connected to the side of the pressure relief structure (22) away from the power-off structure (21).

11. A battery with power-off and pressure relief function, comprising a battery casing (5), characterized in that, The battery housing (5) has an opening at one end; the opening is used to install a busbar (2) as described in any one of claims 1 to 9.

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