Combined battery cover plate, assembling method thereof and battery

Abstract

The invention provides a combined battery cover plate, an assembling method thereof and a battery. The combined battery cover plate comprises a first insulating part, a cover plate, a second insulating part, a sealing ring, a pole and a pressing plate, the pole comprises a first pole section and a second pole section, and the first pole section abuts against one side, deviating from the cover plate, of the first insulating part; the end part, deviating from the second pole, of the first pole section is an external end, the second pole section penetrates through the first insulating part, the cover plate and the second insulating part, and the pressing plate is fixedly connected to the second pole section; the end part, deviating from the first pole, of the second pole section is an internal connection end, and the internal connection end is used for connecting a battery cell tab of the battery; the sealing ring is hermetically connected with the second pole section, the second insulating part, the cover plate and the first insulating part; the pole disclosed by the invention is less in material consumption and lower in cost; and when the battery cells are grouped, the welding area of the chips is larger, the error-tolerant rate is high, the material consumption of the pole is less, and the sealing ring is conical, so that the stress area of the sealing ring can be increased, and the sealing effect of the sealing ring and the safety performance of the battery are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a combined battery cover plate, an assembly method thereof, and a battery. Background Art In the rapidly developing field of new energy vehicles and energy storage systems, battery packs are core energy storage units, and their performance, safety, and cost-effectiveness are key factors in measuring the competitiveness of the entire system. In a battery pack, the battery cover, as the packaging and protection structure of the battery cell, not only carries multiple functions such as sealing, explosion-proofing, and heat dissipation, but is also directly related to the electrical connection and energy transmission efficiency between the battery cells. Among them, the pole, as a key component on the battery cover, is responsible for drawing out the electrical energy inside the battery cell and connecting it to the external circuit. The rationality of its design is crucial to the overall performance of the battery pack.

[0002] However, in the design of traditional battery cover, a common problem is that the volume of the pole is relatively large. This is mainly because the pole needs a sufficient cross-sectional area to ensure low resistance and high stability of the current during transmission, especially in the application scenarios of high energy density and high power output, which puts higher requirements on the conductivity and heat dissipation performance of the pole. Therefore, increasing the volume of the pole has become a common solution, but this also brings problems such as increased material costs, increased weight and reduced space utilization.

[0003] On the other hand, during the grouping process of the battery cells, multiple single battery cells need to be connected in series or in parallel through the bar (also called connecting plate or busbar) to achieve the voltage and capacity requirements of the overall battery pack. Due to the compact arrangement of the battery cells, the space left for the bar welding is limited, resulting in a relatively small welding area. This design not only increases the difficulty of welding, reduces the mechanical strength of the welded joint and the reliability of the electrical connection, but also limits the fault tolerance of the battery pack under complex working conditions. Once a welding point fails, it may quickly spread to the entire battery pack, affecting the safety and stability of the entire system; therefore, how to overcome the above-mentioned technical problems and defects has become a key issue that needs to be solved. Summary of the invention

[0004] In order to solve the problems of large pole volume, relatively small welding area and great welding difficulty, the present invention provides a combined battery cover plate, an assembly method thereof and a battery.

[0005] The technical solution adopted by the present invention to solve the above technical problems is as follows: A first aspect of the present invention provides a combined battery cover plate, comprising a first insulating member, a cover plate, a second insulating member, a sealing ring, a pole and a pressing plate; The first insulating member is arranged on the outer side of the cover plate, and the second insulating member is arranged on the inner side of the cover plate; The pole comprises a first pole segment and a second pole segment connected to the first pole segment; The first pole segment abuts against a side of the first insulating member away from the cover plate; an end of the first pole segment away from the second pole is an external connection end, the external connection end is used for external connection, and an end surface of the external connection end is exposed outside the first insulating member; The second pole segment is passed through the first insulating member, the cover plate and the second insulating member, the pressing plate is fixedly connected to the second pole segment, and the pressing plate abuts against a side of the second insulating member away from the cover plate; the end of the second pole segment away from the first pole is an inner connection end, the inner connection end is used to connect to the battery cell tab of the battery, and the end surface of the inner connection end is exposed outside the pressing plate; The sealing ring seals and connects the second pole segment, the second insulating member, the cover plate and the first insulating member.

[0006] Optionally, the second pole segment includes a first segment connected to the first pole segment, and a second segment connected to the first segment; the outer periphery of the first pole segment protrudes from the outer periphery of the first segment, and the outer periphery of the first segment protrudes from the second segment; The first section is provided through the first insulating member, the cover plate and the second insulating member; The second section is passed through the pressing plate, and the end of the second section away from the first section is an inner connection end; The pressing plate abuts against the end surface of the first section and is fixed to the second section.

[0007] Optionally, an end surface of the second section facing away from the first section is flush with or protrudes from a side of the pressing plate facing away from the second insulating member.

[0008] Optionally, the side length or diameter of the first pole segment is L1mm, the side length or diameter of the first segment is L2mm, the side length or diameter of the second segment is L3mm, L1 and L2 satisfy the relationship: 2.5mm≤L1-L2≤5.5mm; L2 and L3 satisfy the relationship: 1mm≤L2-L3≤3mm.

[0009] Optionally, the outer circumference of the sealing ring gradually increases from one end to the other end of the sealing ring.

[0010] Optionally, a first through hole is provided on the cover plate, a second through hole is provided on the second insulating member at a position corresponding to the first through hole, the second pole segment is passed through the first through hole and the second through hole, and the sealing ring is sleeved on the outer side of the second pole segment; The small end surface of the sealing ring abuts against the first insulating member; The large end surface of the sealing ring abuts against the pressing plate, and the outer wall of the sealing ring abuts against the inner wall of the first through hole and the inner wall of the second through hole; or, The large end surface of the sealing ring abuts against the second insulating member, and the outer wall of the sealing ring abuts against the inner wall of the first through hole.

[0011] Optionally, the first insulating member is provided with an annular convex portion, the annular convex portion extends into one end of the first through hole; the small end surface of the sealing ring abuts against the annular convex portion; or, The first insulating member is located outside the first through hole and blocks the outer ring of the first through hole; the small end face of the sealing ring abuts against the portion of the first insulating member blocking the outer ring of the first through hole.

[0012] Optionally, the inner circumference of the sealing ring is a circular surface, and the outer circumference of the sealing ring is a conical surface; the end of the pole that cooperates with the sealing ring is a cylindrical section; The two axial end surfaces of the sealing end are respectively a first annular plane and a second annular plane.

[0013] Optionally, the cover plate includes a cover plate body and a first boss disposed on the cover plate body, and an outer side of the first boss protrudes out of an outer side of the cover plate body; The first boss is provided with a first groove and the first through hole; the first through hole passes through the bottom of the first groove, and the first insulating member is embedded in the first groove; The first insulating member is provided with a second groove and a third through hole, wherein the third through hole passes through the bottom of the second groove; the first pole segment is embedded in the second groove, and the second pole segment is passed through the third through hole; The groove wall of the first groove limits the rotation of the first insulating member, and the groove wall of the second groove limits the rotation of the first pole segment.

[0014] Optionally, the first groove and the second groove are square grooves, and the first insulating member and the first pole segment are square structures.

[0015] Optionally, a third groove is formed on the inner side of the cover plate, the third groove surrounds the outer periphery of the first through hole, the second insulating member protrudes toward the cover plate to form a second boss, the second boss surrounds the outer periphery of the second through hole, and the second boss is embedded in the third groove.

[0016] Optionally, the second insulating member is recessed toward the cover plate to form a fourth groove, and the pressing plate is embedded in the fourth groove.

[0017] Optionally, a fifth groove is provided on the second insulating member, the fifth groove is closed by the cover plate to form a cavity, and a plurality of air-permeable liquid holes for connecting the cavity and the inner cavity of the battery housing are opened on the fifth groove; The cover plate is provided with a first liquid injection port and an explosion-proof component, the second insulating component is provided with a second liquid injection hole at a position corresponding to the first liquid injection hole, the first liquid injection hole is connected to the second liquid injection hole, and the explosion-proof component is located on the cover plate at a position opposite to the fifth groove.

[0018] A second aspect of the present invention provides a method for assembling a combined battery cover plate, the method comprising the following steps: The first insulating member, the cover plate, the second insulating member, the pole and the sealing ring are assembled into a component 1; wherein: The first insulating member, the cover plate, and the second insulating member are stacked; the pole is passed through the first insulating member, the cover plate, and the second insulating member; the sealing ring is sleeved on the first pole segment and embedded in the cover plate; Assemble the pressing plate on the component 1, and clamp the first pole segment and the pressing plate, so that the first pole segment, the first insulating member, the cover plate, the second insulating member and the pressing plate are pressed in sequence along the thickness direction of the cover plate, and the sealing ring is pressed between the second pole segment, the pressing plate, the second insulating member, the cover plate and the first insulating member, or the sealing ring is pressed between the second pole segment, the second insulating member, the cover plate and the first insulating member; The pressing plate and the second pole segment are welded to obtain the combined battery cover plate.

[0019] A third aspect of the present invention provides a battery, the battery comprising the combined battery cover plate described above, or the combined battery cover plate assembled by the above-mentioned assembly method.

[0020] According to the combined battery cover provided by the present invention, the pole of the present application is installed in an inverted manner, the portion of the first pole segment exposed to the first insulating member is used for external connection, and the portion of the second pole segment exposed to the pressure plate is used for connection with the battery cell, avoiding the need to weld multiple parts in the combined battery cover to achieve circuit connection between the battery cell and circuits outside the combined battery cover, and has a better overcurrent effect; when the battery cells are grouped, the tabs used to connect adjacent battery cells are electrically connected to the first pole segment (such as welding), and the pole ears of the battery cells are electrically connected to the second pole segment (such as welding). While meeting the overcurrent requirements of the battery cells, the first pole segment has a larger connection surface that can be connected to the tabs, has a large fault tolerance, can reduce the size of the pole in a direction perpendicular to its axial direction, uses less material for the pole, and achieves weight reduction and cost reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 is an exploded schematic diagram of a combined battery cover provided by an embodiment of the present invention; Figure 2 It is a schematic structural diagram of a pole in a combined battery cover provided by an embodiment of the present invention; Figure 3 It is a structural schematic diagram of a sealing ring in a combined battery cover provided by an embodiment of the present invention; Figure 4 is a cross-sectional schematic diagram of a combined battery cover provided by an embodiment of the present invention; Figure 5 yes Figure 4 Enlarged view of part A in the middle; Figure 6 is a partial cross-sectional schematic diagram of a combined battery cover provided by another embodiment of the present invention; The reference numerals in the drawings of the specification are as follows: 1-first insulating member; 11-annular convex portion; 12-second groove; 13-third through hole; 2-cover plate; 21-first through hole; 22-cover plate body; 23-first boss; 24-first groove; 25-third groove; 26-first liquid injection port; 27-explosion-proof member; 3-second insulating member; 31-second through hole; 32-second boss; 33-fourth groove; 34-fifth groove; 35-air-permeable liquid hole; 36-second liquid injection hole; 4-sealing ring; 41-circular surface; 42-conical surface; 43-first circular plane; 44-second circular plane; 5-pole; 51-first pole section; 52-second pole section; 521-first section; 522-second section; 6-pressing plate. DETAILED DESCRIPTION

[0023] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0024] In the description of the present invention, it should be understood that the terms "longitudinal", "radial", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0025] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] like Figure 1-Figure 2 As shown, in one embodiment, the first aspect of the present invention provides a combined battery cover, including a first insulating member 1, a cover 2, a second insulating member 3, a sealing ring 4, a pole 5 and a pressing plate 6; The first insulating member 1 is arranged on the outer side of the cover plate 2, and the second insulating member 3 is arranged on the inner side of the cover plate 2; The pole 5 includes a first pole segment 51 and a second pole segment 52 connected to the first pole segment 51; The first pole segment 51 abuts against the side of the first insulating member 1 away from the cover plate 2; the end of the first pole segment 51 away from the second pole 5 is an external connection end, which is used for external connection, and the end surface of the external connection end is exposed outside the first insulating member 1; The second pole section 52 is passed through the first insulating member 1, the cover plate 2 and the second insulating member 3, and the pressing plate 6 is fixedly connected to the second pole section 52, and the pressing plate 6 abuts against the side of the second insulating member 3 away from the cover plate 2; the end of the second pole section 52 away from the first pole 5 is an inner connection end, which is used to connect the battery cell ear, and the end surface of the inner connection end is exposed outside the pressing plate 6; The sealing ring 4 seals and connects the second pole segment 52 , the second insulating member 3 , the cover plate 2 and the first insulating member 1 .

[0027] Compared with the existing pole 5, the pole 5 of the present application is installed in an inverted manner. The portion of the first pole segment 51 exposed to the first insulating member 1 is used for external connection, and the portion of the second pole segment 52 exposed to the pressure plate 6 is used to connect to the battery cell, avoiding the need to weld multiple parts in the combined battery cover to achieve circuit connection between the battery cell and the circuit outside the combined battery cover, and has a better overcurrent effect; when the battery cells are grouped, the bar used to connect adjacent battery cells is electrically connected to the first pole segment 51 (such as welding), and the pole ear of the battery cell is electrically connected to the second pole segment 52 (such as welding). While meeting the overcurrent requirements of the battery cell, the first pole segment 51 has a larger connection surface that can be connected to the bar, has a large fault tolerance, can reduce the size of the pole 5 in a direction perpendicular to its axial direction, uses less material for the pole 5, and achieves weight reduction and cost reduction.

[0028] Specifically, the cover plate is a metal cover plate.

[0029] like Figure 2 As shown, in one embodiment, the second pole segment 52 includes a first segment 521 connected to the first pole segment 51, and a second segment 522 connected to the first segment 521; the outer periphery of the first pole segment 51 protrudes from the outer periphery of the first segment 521, and the outer periphery of the first segment 521 protrudes from the second segment 522; The first section 521 is disposed through the first insulating member 1, the cover plate 2 and the second insulating member 3; The second section 522 is disposed through the pressing plate 6, and the end of the second section 522 away from the first section 521 is an inner connection end; The pressing plate 6 abuts against the end surface of the first section 521 and is fixed to the second section 522 .

[0030] Specifically, the area of ​​the first pole segment 51 is larger than the area of ​​the first segment 521, the area of ​​the first segment 521 is larger than the area of ​​the second segment 522, the sealing ring 4 is sleeved on the outside of the first segment 521, the pressing plate 6 is sleeved on the second segment 522, and abuts against the end of the first segment 521 away from the first pole segment 51. The pressing plate 6 and the first pole segment 51 cooperate to clamp the first insulating member 1, the cover plate 2, the second insulating member 3 and the sealing ring 4, simplifying the structure and assembly of the combined battery cover plate, and ensuring the strength of the pole mounting part of the combined battery cover plate.

[0031] like Figure 4 As shown, in one embodiment, the end surface of the second section 522 facing away from the first section 521 is flush with or protrudes from the side of the pressing plate 6 facing away from the second insulating member 3 .

[0032] Specifically, in some embodiments, the end surface of the second section 522 facing away from the first section 521 is flush with the side of the pressing plate 6 facing away from the second insulating member 3 to facilitate welding of the end surface of the second section 522 facing away from the first section 521 to the tab of the battery cell.

[0033] In other embodiments, the end surface of the second section 522 facing away from the first section 521 protrudes from the side of the pressing plate 6 facing away from the second insulating member 3, so as to facilitate welding of the end surface of the second section 522 facing away from the first section 521 and the tab of the battery cell.

[0034] like Figure 2 As shown, in one embodiment, any one or more of the first pole segment 51, the first segment 521 and the second segment 522 are square column segments or cylindrical segments, the side length or diameter of the first pole segment 51 is L1mm, the side length or diameter of the first segment 521 is L2mm, the side length or diameter of the second segment 522 is L3mm, L1 and L2 satisfy the relationship: 2.5mm≤L1-L2≤5.5mm; L2 and L3 satisfy the relationship: 1mm≤L2-L3≤3mm. In this way, the current capacity of the pole is ensured, and there is sufficient overlapping area between the pressing plate 6 and the second segment 522, and between the first pole segment 51 and the first insulating member 1, and the pressing plate 6 is simultaneously facing the first insulating member 1, the second segment 522, the cover plate 2 and the first insulating member 1, which is conducive to ensuring the strength of the installation part of the combined battery cover pole.

[0035] Specifically, the difference between L1 and L2 is: 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, 5mm, 5.1mm, 5.2mm, 5.3mm, 5.4mm or 5.5mm, any point value or a range value consisting of any two point values.

[0036] In a preferred embodiment, L1 and L2 satisfy the relationship: 3mm≤L1-L2≤4mm. Specifically, the difference between L2 and L3 is: any point value among 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm or 3mm, or a range consisting of any two point values.

[0037] In a preferred embodiment, L2 and L3 satisfy the relationship: 1.5 mm ≤ L2 - L3 ≤ 2.5 mm.

[0038] Through the above Preferably, the first pole segment 51 is a square column segment, the first segment 521 and the second segment 522 are cylindrical segments, L1 and L2 satisfy the relationship: 2.5mm≤L1-L2≤5.5mm; L2 and L3 satisfy the relationship: 1mm≤L2-L3≤3mm; thereby ensuring that there is sufficient torque between the first pole segment 51, the first insulating member 1 and the cover plate 2, so that the pole 5 and the first insulating member 1 do not rotate during the use of the battery module, thereby meeting the torque requirements of the pole assembly.

[0039] By making the cross-sectional area of ​​the first pole segment 51 larger than the cross-sectional area of ​​the first segment 521, and the cross-sectional area of ​​the first segment 521 larger than the cross-sectional area of ​​the second segment 522, the pole 5 is installed in an inverted manner, avoiding the need to weld multiple parts in the combined battery cover to achieve circuit connection between the battery cell and the circuit outside the combined battery cover, and having a better overcurrent effect; when the battery cells are grouped, the tabs used to connect adjacent battery cells are electrically connected to the first pole segment 51 (such as welding), and the tabs of the battery cells are electrically connected to the second pole segment 52 (such as welding). While meeting the overcurrent requirements of the battery cells, the first pole segment 51 has a larger connection surface that can be connected to the tabs, has a large fault tolerance, can reduce the size of the pole 5 in a direction perpendicular to its axial direction, uses less material for the pole 5, and achieves weight reduction and cost reduction.

[0040] like Figure 3 As shown, in one embodiment, the outer circumference of the sealing ring 4 gradually increases from one end of the sealing ring 4 to the other end.

[0041] According to the combined battery cover provided by the present invention, by designing the sealing ring 4 into the above-mentioned form, the structure of the sealing ring 4 is simplified, the sealing ring 4 is embedded between the first insulating member 1, the cover plate 2, the second insulating member 3 and the pole 5, or the sealing ring 4 is embedded between the first insulating member 1, the cover plate 2, the second insulating member 3, the pole 5 and the pressing plate 6, and the first insulating member 1, the cover plate 2, the second insulating member 3, the pole 5 and the pressing plate 6 are pressed and fixed, that is, the assembly of the sealing ring 4, the first insulating member 1, the cover plate 2, the second insulating member 3, the pole 5 and the pressing plate 6 is completed; along the direction from one end of the sealing ring 4 to the other end, the outer circumference size of the sealing ring 4 The pressure gradually increases, so that the assembled sealing ring 4 has a larger compressive stress, and an inclined sealing surface is formed between the outer side of the sealing ring 4 and the cover plate 2 (and the second insulating member 3), which is beneficial to improving the sealing performance; the sealing ring 4 compressed between the first insulating member 1 and the second insulating member 3 (or the pressing plate 6) can disperse the force along its axial direction, the direction parallel to its axial direction and the inclined direction, avoid local stress concentration leading to sealing failure, increase the service life of the sealing ring 4, prevent the electrolyte from overflowing from the gap between the first insulating member 1, the cover plate 2, the second insulating member 3, the pole 5 and the pressing plate 6, and improve the safety performance of the battery.

[0042] like Figure 1 and Figure 4As shown, in one embodiment, the cover plate 2 is provided with a first through hole 21, the second insulating member 3 is provided with a second through hole 31 at a position corresponding to the first through hole 21, the second pole section 52 is penetrated through the first through hole 21 and the second through hole 31, and a sealing ring 4 is sleeved on the outer side of the second pole section 52; The small end surface of the sealing ring 4 abuts against the first insulating member 1; The large end surface of the sealing ring 4 abuts against the pressing plate 6, and the outer wall of the sealing ring 4 abuts against the inner wall of the first through hole 21 and the inner wall of the second through hole 31; or, The large end surface of the sealing ring 4 abuts against the second insulating member 3 , and the outer wall of the sealing ring 4 abuts against the inner wall of the first through hole 21 .

[0043] Specifically, in one embodiment, the first through hole 21 and the second through hole 31 are both tapered holes, and the angle between the busbar of the first through hole 21 and the busbar of the second through hole 31 and the axis of the pole 5 is the same as the angle between the busbar of the conical surface 42 of the sealing ring 4 and the axis of the pole 5, so that the outer peripheral surface of the sealing ring 4 and the cover plate 2 and the second insulating member 3 can fit more closely, and the sealing ring 4 can be inserted into the first through hole 21 and the second through hole 31; the small end face of the sealing ring 4 abuts against the lower surface of the first insulating member 1; the large end face of the sealing ring 4 abuts against the upper surface of the pressure plate 6.

[0044] Specifically, in another embodiment, the first through hole 21 is a tapered hole, and the angle between the busbar of the first through hole 21 and the axis of the pole 5 is the same as the angle between the busbar of the conical surface 42 of the sealing ring 4 and the axis of the pole 5, so that the outer peripheral surface of the sealing ring 4 and the cover plate 2 can fit more closely, and the sealing ring 4 can be inserted into the first through hole 21; the small end face of the sealing ring 4 abuts against the lower surface of the first insulating member 1; the large end face of the sealing ring 4 abuts against the upper surface of the second insulating member 3.

[0045] like Figure 1 and Figure 4 As shown, in one embodiment, the first insulating member 1 is provided with an annular protrusion 11, and the annular protrusion 11 extends into one end of the first through hole 21; the small end surface of the sealing ring 4 abuts against the annular protrusion 11; and sealing can be achieved. Preferably, the first insulating member 1 is located outside the first through hole 21 and blocks the outer ring of the first through hole 21; the small end face of the sealing ring 4 abuts against the portion of the first insulating member 1 that blocks the outer ring of the first through hole 21; and the relatively increased height of the sealing ring 4 has a better sealing effect.

[0046] like Figure 6As shown, in one embodiment, an annular protrusion 11 is provided on one side of the first insulating member 1 facing the cover plate 2, the annular protrusion 11 extends into one end of the first through hole 21, the sealing ring 4 is located in the first through hole 21, and the upper end surface of the sealing ring 4 abuts against the bottom surface of the end of the annular protrusion 11 of the first insulating member 1 extending into the first through hole 21, thereby avoiding the outer surface of the pole 5 from contacting the inner surface of the first through hole 21; the sealing effect of the sealing ring 4 is improved.

[0047] like Figure 5 As shown, in one embodiment, the first insulating member 1 is located outside the first through hole 21 and blocks the outer ring of the first through hole 21; the small end face of the sealing ring 4 abuts against the portion of the first insulating member 1 blocking the outer ring of the first through hole 21, thereby preventing the outer surface of the pole 5 from contacting the inner surface of the first through hole 21; the sealing effect of the sealing ring 4 is improved.

[0048] like Figure 3 As shown, in one embodiment, the inner circumference of the sealing ring 4 is a circular surface 41, and the outer circumference of the sealing ring 4 is a conical surface 42; the end of the pole 5 that cooperates with the sealing ring 4 is a cylindrical section; The two axial end surfaces of the sealing end are respectively a first annular plane 43 and a second annular plane 44 .

[0049] This is not only conducive to the processing and forming of the sealing ring 4, but also makes it easier to insert the sealing ring 4 between the cover plate 2, the second insulating member 3 and the pole 5. Since the inner circumference of the sealing ring 4 is a circular surface 41, when the sealing ring 4 is compressed, its inner circumference can be well matched with the pole 5. At the same time, the outer circumference of the sealing ring 4 is a conical surface 42, so that the outer circumference of the sealing ring 4 can be more closely fitted with the first insulating member 1, the cover plate 2, the second insulating member 3 and the pressing plate 6, so that the outer circumference of the sealing ring 4 and the first insulating member 1, the cover plate 2, the second insulating member 3 and the pressing plate 6 are more closely matched, thereby improving the sealing effect of the sealing ring 4.

[0050] Specifically, the first circular plane 43 and the second circular plane 44 of the sealing ring 4 are both planar. Such a design facilitates the processing and manufacturing of the sealing ring 4 on the one hand, and on the other hand, it also facilitates the first circular plane 43 of the sealing ring 4 to fit more closely with the lower surface of the first insulating member 1; the second circular plane 44 and the upper surface of the pressure plate 6 to fit more closely.

[0051] like Figure 1 As shown, in one embodiment, the cover plate 2 includes a cover plate body 22 and a first boss 23 disposed on the cover plate body 22, and the outer side of the first boss 23 protrudes from the outer side of the cover plate body 22; The first boss 23 is provided with a first groove 24 and a first through hole 21; the first through hole 21 passes through the bottom of the first groove 24, and the first insulating member 1 is embedded in the first groove 24; The first insulating member 1 is provided with a second groove 12 and a third through hole 13, wherein the third through hole 13 passes through the bottom of the second groove 12; the first pole segment 51 is embedded in the second groove 12, and the second pole segment 52 is passed through the third through hole 13; The groove wall of the first groove 24 limits the rotation of the first insulating member 1 , and the groove wall of the second groove 12 limits the rotation of the first pole segment 51 .

[0052] Specifically, the groove wall of the first groove 24 limits the rotation of the first insulating member 1, thereby enhancing the structural strength between the first insulating member 1 and the cover plate 2, making the connection between them more reliable.

[0053] The groove wall of the second groove 12 limits the rotation of the first pole segment 51, thereby enhancing the structural strength between the first insulating member 1 and the first pole segment 51 and making the connection more reliable.

[0054] Furthermore, the diameter of the first through hole 21 is greater than the diameter of the third through hole 13, and the end face of the small end of the sealing ring 4 extends into the first through hole 21 and is flush with the upper surface of the first through hole 21, so that the end face of the small end of the sealing ring 4 abuts against the first insulating member 1. Under the isolation of the sealing ring 4 and the first insulating member 1, the pole 5 is prevented from contacting the cover plate 2 assembly, thereby improving the sealing effect of the sealing ring 4.

[0055] like Figure 1 As shown, in one embodiment, the first groove 24 and the second groove 12 are square grooves, and the first insulating member 1 and the first pole segment 51 are square structures.

[0056] Specifically, the first boss 23, the first groove 24 and the first insulating member 1 are all square in shape, thereby preventing the first insulating member 1 from twisting in the first groove 24, enhancing the structural strength between the first insulating member 1 and the cover plate 2, and making the connection more reliable.

[0057] Specifically, the second groove 12 and the first pole segment 51 are both square in shape, thereby preventing the first pole segment 51 from twisting in the second groove 12, enhancing the structural strength between the first insulating member 1 and the first pole segment 51, and making the connection more reliable.

[0058] Furthermore, the shapes of the first boss 23 , the first groove 24 and the first insulating member 1 may also be other non-circular shapes, which can prevent the first insulating member 1 from twisting in the first groove 24 .

[0059] Furthermore, the shapes of the second groove 12 and the first pole segment 51 may also be other non-circular shapes, both of which can prevent the first pole segment 51 from twisting in the first insulating member 1 .

[0060] like Figure 4As shown, in one embodiment, a third groove 25 is formed on the inner side of the cover plate 2, and the third groove 25 surrounds the outer periphery of the first through hole 21. The second insulating member 3 protrudes toward the cover plate 2 to form a second boss 32, and the second boss 32 surrounds the outer periphery of the second through hole 31. The second boss 32 is embedded in the third groove 25.

[0061] Specifically, the second boss 32 is embedded in the third groove 25, so as to avoid displacement between the second insulating member 3 and the cover plate 2, so that the structure of the second insulating member 3 and the cover plate 2 is more compact, stronger and more reliable in sealing performance.

[0062] like Figure 4 As shown, in one embodiment, the second insulating member 3 is recessed toward the cover plate 2 to form a fourth groove 33 , and the pressing plate 6 is embedded in the fourth groove 33 .

[0063] Specifically, a fourth groove 33 is formed by recessing the second insulating member 3 in a direction toward the cover plate 2, and the pressing plate 6 is embedded in the fourth groove 33, which can not only avoid displacement between the pressing plate 6 and the second insulating member 3, but also make the structure between the pressing plate 6 and the second insulating member 3 more compact, stronger, and more reliable in sealing performance.

[0064] like Figure 4 As shown, in one embodiment, a fifth groove 34 is provided on the second insulating member 3, the fifth groove 34 is closed by the cover plate 2 to form a cavity, and a plurality of air-permeable liquid holes 35 for connecting the cavity and the inner cavity of the battery housing are opened on the fifth groove 34; A first liquid injection port 26 and an explosion-proof component 27 are provided on the cover plate 2. A second liquid injection hole 36 is provided on the second insulating component 3 at a position corresponding to the first liquid injection hole. The first liquid injection hole is connected to the second liquid injection hole 36. The explosion-proof component 27 is located on the cover plate 2 at a position opposite to the fifth groove 34.

[0065] Specifically, the fifth groove 34 abuts against the surface of the battery cell to prevent the battery cell from moving. A plurality of air-permeable liquid holes 35 are provided at the bottom of the fifth groove 34. The fifth groove 34 has the function of storing a certain amount of electrolyte, thereby increasing the overall liquid retention of the battery. During the battery cycle, the electrolyte will be consumed to a certain extent. At this time, the electrolyte stored in the fifth groove 34 can be used to supplement the electrolyte loss caused by the battery cycle.

[0066] Furthermore, the fifth groove 34 abuts against the surface of the battery cell, thereby preventing the battery cell from moving and improving the stability of the battery.

[0067] Specifically, the first injection hole is connected to the second injection hole 36 to form an injection hole, and the battery is injected with electrolyte through the first injection hole and the second injection hole 36. The electrolyte enters the inner cavity of the battery shell through the first injection hole and the second injection hole 36. After the injection or formation is completed, the first injection hole is closed. The closing method can be achieved by welding the cover plate 2 or setting an openable cover plate 2.

[0068] In this embodiment, the explosion-proof component 27 is selected from an explosion-proof valve or other components with explosion-proof function.

[0069] The explosion-proof valve of the present application is provided with an annular groove to form a structural weak point on the explosion-proof valve. When the battery has thermal runaway, a large amount of gas will be generated. The gas enters the cavity of the annular groove through the air-permeable liquid hole 35. The large amount of gas causes the internal pressure of the battery to increase, and then the explosion-proof valve breaks at the annular groove to form an opening, which has a pressure relief effect on the battery, and finally avoids the battery from exploding due to excessive pressure.

[0070] In one embodiment, the second aspect of the present invention provides a method for assembling a combined battery cover, the method comprising the following steps: The first insulating member 1, the cover plate 2, the second insulating member 3, the pole 5 and the sealing ring 4 are assembled into a component 1; in the component 1: The first insulating member 1, the cover plate 2, and the second insulating member 3 are stacked; the pole 5 is passed through the first insulating member 1, the cover plate 2, and the second insulating member 3; the sealing ring 4 is sleeved on the first pole section 51 and embedded in the cover plate 2; Assemble the pressing plate 6 on the component 1, and clamp the first pole segment 51 and the pressing plate 6, so that the first pole segment 51, the first insulating member 1, the cover plate 2, the second insulating member 3 and the pressing plate 6 are pressed in sequence along the thickness direction of the cover plate 2, and the sealing ring 4 is elastically pressed between the second pole segment, the pressing plate 6, the second insulating member 3, the cover plate 2 and the first insulating member 1, or the sealing ring 4 is elastically pressed between the second pole segment, the second insulating member 3, the cover plate 2 and the first insulating member 1; The pressing plate 6 and the second pole section 52 are welded to obtain a combined battery cover.

[0071] Specifically, during the assembly process, the first insulating member 1, the cover plate 2, and the second insulating member 3 are first stacked, and then the sealing ring 4 is pressed onto the cover plate 2 and the second insulating member 3. Finally, the pole 5 is passed through the first insulating member 1 and the sealing ring 4, and then the pressing plate 6 is placed on the side of the second insulating member 3 away from the cover plate 2, and the upper end surface of the sealing ring 4 abuts against the bottom surface of the first insulating member 1, and the lower end surface of the sealing ring 4 abuts against the upper surface of the pressing plate 6. In this way, the force-bearing area of ​​the sealing ring 4 can be increased, and then the filling amount of the sealing ring 4 in the gap between the first insulating member 1, the cover plate 2, the second insulating member 3, the pole 5 and the pressing plate 6 is increased, so that the sealing ring 4 can better fit between the first insulating member 1, the cover plate 2, the second insulating member 3, the pole 5 and the pressing plate 6, thereby improving the sealing effect of the sealing ring 4. Specifically, the pole 5 of the present application includes a first pole section 51 and a second pole section 52. The pole 5 of the present application is installed in an inverted manner. The first pole section 51 is located in the second groove 12 of the first insulating member 1. The second pole section 52 is sleeved with a sealing ring 4 on the outside. While meeting the overcurrent requirements of the battery cell, the sealing ring 4 is used to seal the pole 5. Less material is used, and the cost is lower; and the pole 5 is installed in an inverted manner. While meeting the requirements, the welding area of ​​the bar sheet is larger when the battery cells are grouped, the fault tolerance rate is large, and the pole 5 uses less material; The sealing ring 4 is conical, which can increase the force-bearing area of ​​the sealing ring 4, thereby increasing the amount of the sealing ring 4 filling the gap between the first insulating member 1, the cover plate 2, the second insulating member 3, the pole 5 and the pressing plate 6, so that the sealing ring 4 can better fit between the first insulating member 1, the cover plate 2, the second insulating member 3, the pole 5 and the pressing plate 6, thereby improving the sealing effect of the sealing ring 4, preventing the electrolyte from overflowing from the gap between the first insulating member 1, the cover plate 2, the second insulating member 3, the pole 5 and the pressing plate 6, and improving the safety performance of the lithium-ion battery. In one embodiment, the third aspect of the present invention provides a battery, the battery includes the above-mentioned combined battery cover, or the combined battery cover assembled by the above-mentioned assembly method.

[0072] In one embodiment, the battery housing is a semi-enclosed housing with an opening at one end, and the combined battery cover plate closes the opening at one end of the battery housing.

[0073] In another embodiment, the battery housing is a cylindrical housing with openings at both ends, and the number of combined battery covers is two. The combined battery cover plate respectively closes the openings at both ends of the battery shell.

[0074] In some embodiments, the battery housing is a square housing, a cylindrical housing, a prismatic housing or other irregular housings.

[0075] The battery disclosed in the embodiment of the present application can be used in various energy storage systems that use batteries as power sources or use batteries as energy storage elements. The electrical device can be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, and the like. The vehicle can be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, etc.; the spacecraft includes an airplane, a rocket, a space shuttle, and a spacecraft, etc.; the electric toy includes a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc.; the electric tool includes a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and a railway electric tool, for example, an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, and an electric planer, etc.

[0076] The above description is only a preferred embodiment of the present invention and is 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 in the protection scope of the present invention.

Claims

1. A combined battery cover, characterized in that: It includes a first insulating member, a cover plate, a second insulating member, a sealing ring, a pole and a pressing plate; The first insulating member is disposed on the outer side of the cover plate, and the second insulating member is disposed on the inner side of the cover plate; The pole comprises a first pole segment and a second pole segment connected to the first pole segment; The first pole segment abuts against a side of the first insulating member away from the cover plate; an end of the first pole segment away from the second pole is an external connection end, the external connection end is used for external connection, and an end surface of the external connection end is exposed outside the first insulating member; The second pole segment is passed through the first insulating member, the cover plate and the second insulating member, the pressing plate is fixedly connected to the second pole segment, and the pressing plate abuts against a side of the second insulating member away from the cover plate; the end of the second pole segment away from the first pole is an inner connection end, the inner connection end is used to connect to the battery cell tab of the battery, and the end surface of the inner connection end is exposed outside the pressing plate; The sealing ring seals and connects the second pole segment, the second insulating member, the cover plate and the first insulating member.

2. The combined battery cover according to claim 1, characterized in that: The second pole segment includes a first segment connected to the first pole segment and a second segment connected to the first segment; the outer periphery of the first pole segment protrudes from the outer periphery of the first segment, and the outer periphery of the first segment protrudes from the second segment; The first section is provided through the first insulating member, the cover plate and the second insulating member; The second section is passed through the pressing plate, and the end of the second section away from the first section is an inner connection end; The pressing plate abuts against the end surface of the first section and is fixed to the second section.

3. The combined battery cover according to claim 2, characterized in that: An end surface of the second section facing away from the first section is flush with or protrudes from a side of the pressing plate facing away from the second insulating member.

4. The combined battery cover according to claim 2, characterized in that: The side length or diameter of the first pole segment is L1mm, the side length or diameter of the first segment is L2mm, the side length or diameter of the second segment is L3mm, L1 and L2 satisfy the relationship: 2.5mm≤L1-L2≤5.5mm; L2 and L3 satisfy the relationship: 1mm≤L2-L3≤3mm.

5. The combined battery cover according to any one of claims 1 to 4, characterized in that: The outer circumference size of the sealing ring gradually increases from one end to the other end of the sealing ring.

6. The combined battery cover according to claim 5, characterized in that: The cover plate is provided with a first through hole, the second insulating member is provided with a second through hole at a position corresponding to the first through hole, the second pole section is passed through the first through hole and the second through hole, and the sealing ring is sleeved on the outer side of the second pole section; The small end surface of the sealing ring abuts against the first insulating member; The large end surface of the sealing ring abuts against the pressing plate, and the outer wall of the sealing ring abuts against the inner wall of the first through hole and the inner wall of the second through hole; or, The large end surface of the sealing ring abuts against the second insulating member, and the outer wall of the sealing ring abuts against the inner wall of the first through hole.

7. The combined battery cover according to claim 6, characterized in that: The first insulating member is provided with an annular convex portion, the annular convex portion extends into one end of the first through hole, and the small end surface of the sealing ring abuts against the annular convex portion; or, The first insulating member is located outside the first through hole and blocks the outer ring of the first through hole; the small end face of the sealing ring abuts against the portion of the first insulating member blocking the outer ring of the first through hole.

8. The combined battery cover according to claim 1, characterized in that: The inner circumference of the sealing ring is a circular surface, and the outer circumference of the sealing ring is a conical surface; the end of the pole that cooperates with the sealing ring is a cylindrical section; The two axial end surfaces of the sealing end are respectively a first annular plane and a second annular plane.

9. The combined battery cover according to claim 6, characterized in that: The cover plate comprises a cover plate body and a first boss disposed on the cover plate body, wherein the outer side of the first boss protrudes out of the outer side of the cover plate body; The first boss is provided with a first groove and the first through hole; the first through hole passes through the bottom of the first groove, and the first insulating member is embedded in the first groove; The first insulating member is provided with a second groove and a third through hole, wherein the third through hole passes through the bottom of the second groove; the first pole segment is embedded in the second groove, and the second pole segment is passed through the third through hole; The groove wall of the first groove limits the rotation of the first insulating member, and the groove wall of the second groove limits the rotation of the first pole segment.

10. The combined battery cover according to claim 9, characterized in that: The first groove and the second groove are square grooves, and the first insulating member and the first pole segment are square structures.

11. The combined battery cover according to claim 6, characterized in that: A third groove is formed on the inner side of the cover plate, and the third groove surrounds the outer periphery of the first through hole. The second insulating member protrudes toward the cover plate to form a second boss, and the second boss surrounds the outer periphery of the second through hole, and the second boss is embedded in the third groove.

12. The combined battery cover according to claim 1, characterized in that: The second insulating member is recessed toward the cover plate to form a fourth groove, and the pressing plate is embedded in the fourth groove.

13. The combined battery cover according to claim 1, characterized in that: The second insulating member is provided with a fifth groove, the fifth groove is closed by the cover plate to form a cavity, and the fifth groove is provided with a plurality of air-permeable liquid holes for connecting the cavity and the inner cavity of the battery housing; The cover plate is provided with a first liquid injection port and an explosion-proof component, the second insulating component is provided with a second liquid injection hole at a position corresponding to the first liquid injection hole, the first liquid injection hole is connected to the second liquid injection hole, and the explosion-proof component is located on the cover plate at a position opposite to the fifth groove.

14. An assembly method of a combined battery cover according to any one of claims 1 to 13, characterized in that: The method comprises the following steps: The first insulating member, the cover plate, the second insulating member, the pole and the sealing ring are assembled into a component 1; wherein: The first insulating member, the cover plate, and the second insulating member are stacked; the pole is passed through the first insulating member, the cover plate, and the second insulating member; the sealing ring is sleeved on the first pole segment and embedded in the cover plate; Assemble the pressing plate on the component 1, and clamp the first pole segment and the pressing plate, so that the first pole segment, the first insulating member, the cover plate, the second insulating member and the pressing plate are pressed in sequence along the thickness direction of the cover plate, and the sealing ring is pressed between the second pole segment, the pressing plate, the second insulating member, the cover plate and the first insulating member, or the sealing ring is pressed between the second pole segment, the second insulating member, the cover plate and the first insulating member; The pressing plate and the second pole segment are welded to obtain the combined battery cover plate.

15. A battery, characterized in that: The battery comprises the combined battery cover plate according to any one of claims 1 to 13, or the combined battery cover plate assembled by the assembly method according to claim 14.

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