Cover plate assembly and battery

Abstract

The utility model relates to the technical field of batteries, and discloses a cover plate assembly and a battery, the cover plate assembly comprises: a cover plate, which is provided with a pole through hole and a welding through hole, and the welding through hole is suitable for being arranged to directly face a tab on a pole group; the pole is arranged in the pole through hole in a penetrating manner and is riveted on the cover plate, a connecting hole is formed in the pole, and the connecting hole penetrates through the pole along the extension direction of the center line of the pole; the connecting piece comprises a connecting piece body and a welding part, the welding part protrudes out of the upper surface of the connecting piece body, the wall thickness of the welding part is equal to that of the connecting piece body, and the outer circumferential wall of the welding part is attached to and welded to the inner circumferential wall of the connecting hole; the sealing plate is arranged in the welding through hole in a covering mode so as to seal the welding through hole, the sealing plate comprises a plate body and a convex rib, the convex rib protrudes out of the upper surface of the plate body, the size of the convex rib in the vertical direction is H, the size of the plate body in the vertical direction is t, and H is larger than or equal to 0.5 t and smaller than or equal to 1.2 t. The battery internal space utilization rate and the cover plate assembly strength are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a cover plate assembly and a battery. Background Art

[0002] The cover plate assembly is an important structure in the battery. It is arranged at the opening end of the housing to seal the housing. The cover plate assembly mainly consists of a cover plate, a pole column, a connecting piece, etc. Among them, the pole column penetrates through the cover plate. One end of the pole column faces the inside of the battery and the other end faces the outside of the battery. The connecting piece is arranged on the side of the cover plate facing the inside of the battery and is connected between the pole ear on the pole group inside the battery. In the existing cover plate assembly, the upper surface of the connecting piece is usually welded to the lower surface of the pole column. Then, during the battery assembly process, the upper surface of the bent pole ear is welded to the lower surface of the connecting piece to achieve the separate connection of the connecting piece with the pole column and the pole group.

[0003] However, the way that the bent pole ear, the connecting piece, and the pole column are arranged and connected in sequence along the height direction of the battery makes the overall structure occupy too much size in the height direction of the battery, resulting in low space utilization rate inside the battery. Moreover, since the cover plate is also provided with structures such as a pole column through hole for passing through the pole column, a liquid injection hole, and an explosion-proof valve, the structural strength of the cover plate is reduced, leading to relatively weak overall structural strength of the cover plate assembly and poor stability of the battery. Summary of the Utility Model

[0004] In view of this, the utility model provides a cover plate assembly and a battery to solve the problems of low space utilization rate inside the battery and relatively weak structural strength of the cover plate assembly.

[0005] In a first aspect, the utility model provides a cover plate assembly, including: a cover plate, provided with a pole column through hole and a welding through hole, and the welding through hole is adapted to be arranged opposite to the pole ear on the pole group; a pole column, penetrating through the pole column through hole and riveted on the cover plate, a connection hole is opened on the pole column, and the connection hole penetrates through the pole column along the extending direction of the center line of the pole column; a connecting piece, including a connecting piece body and a welding part, the welding part protrudes from the upper surface of the connecting piece body, the wall thickness of the welding part is equal to the thickness of the connecting piece body, and the outer peripheral wall of the welding part is attached to and welded with the inner peripheral wall of the connection hole; a sealing plate, covering the welding through hole to seal the welding through hole, the sealing plate includes a plate body and a convex rib, the convex rib protrudes from the upper surface of the plate body, the size of the convex rib in the up and down direction is H, and the size of the plate body in the up and down direction is t, where 0.5t ≤ H ≤ 1.2t.

[0006] Beneficial effects: By providing that the terminal post has a connection hole penetrating in the up-down direction and the connecting member has a welding portion protruding upward, the welding portion can extend into the connection hole, and the outer peripheral wall of the welding portion is welded to the inner wall of the connection hole to achieve the electrical connection between the connecting member and the terminal post. Compared with the conventional matching method in which the upper surface of the connecting member abuts against the lower surface of the terminal post, the structural form in which the welding portion extends into the connection hole and cooperates with the connection hole reduces the total dimension in the up-down direction after the connecting member and the terminal post are matched, relatively increases the installation space of other components such as the electrode group inside the battery, and thus can improve the utilization rate of the internal space of the battery; By providing welding through-holes corresponding to the electrode tabs on the cover plate, it is convenient for the welding head of the welding equipment to pass through the welding through-holes to weld the electrode tabs and the connecting member after the cover plate and the battery case are assembled. The operation is convenient and it is easy to observe the welding condition between the electrode tabs and the connecting member, thereby improving the battery yield. And by providing that the sealing plate covers the welding through-hole to seal the welding through-hole, the sealing performance of the battery is ensured. The convex ribs provided on the upper surface of the sealing plate can increase the structural strength of the sealing plate and improve the reliability of the cover plate assembly. At the same time, by providing that the dimension H of the convex rib in the up-down direction and the dimension t of the plate body in the up-down direction satisfy the relational expression 0.5t ≤ H ≤ 1.2t, it can not only ensure that the convex rib has a sufficient strengthening effect on the structural strength of the sealing plate, but also avoid the excessive weight of the sealing plate.

[0007] In an alternative embodiment, the number of the convex ribs is at least two, including a transverse rib and at least one annular rib. The annular rib is arranged circumferentially around the transverse rib, and two adjacent convex ribs are arranged at intervals.

[0008] Beneficial effects: By providing that the number of the convex ribs is multiple and two adjacent convex ribs are arranged at intervals, and the multiple convex ribs are distributed on the upper surface of the plate body, an uneven structure form of concave and convex alternation is formed on the upper side of the sealing plate, which can fully increase the structural strength of the sealing plate. And by providing that the multiple convex ribs include a transverse rib and at least one annular rib and the annular rib is arranged circumferentially around the transverse rib, the space on the upper surface of the plate body can be fully utilized, and the coverage area of the convex ribs on the upper surface of the plate body can be increased as much as possible, thereby further improving the structural strength of the sealing plate.

[0009] In an alternative embodiment, the value range of the width W1 of the annular rib is: 0.3t ≤ W1 ≤ 2t; and / or, the value range of the distance W2 between two adjacent convex ribs is: 0.3t ≤ W2 ≤ 2t.

[0010] Beneficial effects: By setting the width W1 of the annular rib to be within the range of 0.3t to 2t, the width dimension of the annular rib is associated with the thickness of the plate body, which can not only ensure the smooth forming of the annular rib, but also ensure that the annular rib can increase the strength of the sealing plate, thereby ensuring the reliability of the cover assembly and the stability of the battery performance. By setting the distance W2 between two adjacent convex ribs to be within the range of 0.3t to 2t, the interval between the two convex ribs is associated with the thickness of the plate body, which is not only convenient for processing, but also can ensure the enhanced structural strength of the sealing plate.

[0011] In an alternative embodiment, a concave rib is formed on the lower surface of the sealing plate, the concave rib corresponding to the convex rib. The concave rib is formed by a partial area on the lower surface of the sealing plate being recessed in a direction close to the upper surface of the sealing plate, and the recessed depth of the concave rib is less than the dimension t of the plate body in the up-down direction.

[0012] Beneficial effects: By forming a concave rib corresponding to the convex rib on the lower surface of the sealing plate, the lower surface of the sealing plate has an alternating concave and convex structure, further strengthening the structural strength of the sealing plate. And the concave rib corresponds to the convex rib and the recessed depth of the concave rib is less than the dimension t of the plate body in the up-down direction, which can avoid having an overly thin area on the sealing plate in the up-down direction, also improving the structural strength of the sealing plate.

[0013] In an alternative embodiment, the wall thickness T1 of the welding part ≥ 1.5 mm; and / or, the upper surface of the welding part is located below the plane where the upper surface of the pole column is located.

[0014] Beneficial effects: By setting the wall thickness T1 of the welding part to be greater than or equal to 1.5 mm, it can ensure that the welding part has sufficient welding strength and connection strength, thus ensuring the reliability and safety of the cover assembly. By setting the upper surface of the welding part to be below the plane where the upper surface of the pole column is located, that is, the upper surface of the welding part is lower than the upper surface of the pole column, it can prevent the weld formed after welding the welding part and the pole column from protruding above the upper surface of the pole column, thereby avoiding affecting the welding of the pole column and the bus bar, ensuring that the pole column has sufficient current-carrying area, and improving the battery quality.

[0015] In an alternative embodiment, the connection hole is a circular hole, and the value range of the diameter R0 of the circular hole is: 4.5 mm ≤ R0 ≤ 30 mm, and the wall thickness W0 of the side wall of the pole column ≥ 1.5 mm.

[0016] Beneficial effects: By setting the diameter R0 of the connection hole to be within the range of 4.5 mm to 30 mm and the wall thickness W0 of the side wall of the pole column to be greater than or equal to 1.5 mm, it is ensured that when the pole column is riveted to the cover plate, the connection hole will not deform, thus ensuring the assembly and welding effect between the connection hole and the welding part.

[0017] In an alternative embodiment, the circumferential edge of the upper surface of the welding portion is configured as a first guiding angle, and the lower edge of the connecting hole is configured as a second guiding angle. The second guiding angle cooperates with the first guiding angle and is adapted to guide the welding portion to be inserted into the connecting hole upward from the lower side of the pole column.

[0018] Advantageous effects: The second guiding angle and the first guiding angle guide the movement of the welding portion into the connecting hole, ensuring that the welding portion can be smoothly inserted into the connecting hole, thereby ensuring the smooth cooperation between the connecting member and the pole column, which is beneficial to improving work efficiency.

[0019] In an alternative embodiment, both the first guiding angle and the second guiding angle are guiding rounded corners, and the radius of the circle where the second guiding angle is located is greater than or equal to 0.2 mm.

[0020] Advantageous effects: The rounded corner has better guiding performance, and the rounded corner enables the surface of the pole column to have a smooth transition at this position, which can avoid stress concentration. By setting the radius of the circle where the second guiding angle is located to be greater than or equal to 0.2 mm, it is possible to avoid insufficient guiding effect due to too small a guiding angle, thereby further ensuring that the welding portion can be smoothly inserted into the connecting hole.

[0021] In an alternative embodiment, the value range of the dimension t of the plate body in the up-down direction is: 0.35 mm - 0.8 mm; and / or, the value range of the dimension T0 of the cover plate in the up-down direction is 1.5 mm - 2 mm.

[0022] Advantageous effects: By setting the thickness t of the plate body to be within the range of 0.35 mm to 0.8 mm, it can not only ensure that the sealing plate has sufficient strength to ensure the reliability of the cover plate assembly, but also can reduce the weight and cost of the sealing plate as much as possible, and can also save the internal space of the battery and improve the space utilization rate, thereby being beneficial to improving the overall energy density of the battery. By setting the thickness T0 of the cover plate to be within the range of 1.5 mm to 2 mm, it can not only ensure that the cover plate has sufficient strength to ensure the reliability of the cover plate assembly, but also can reduce the weight and cost of the cover plate as much as possible, thereby being beneficial to improving the overall energy density of the battery.

[0023] In a second aspect, the present utility model further provides a battery, including: a housing, one end of which is set as an open end; a pole group, arranged in the inner cavity of the housing, and the pole group has a pole tab arranged towards the open end of the housing; the above-mentioned cover plate assembly, arranged at the open end of the housing to close the housing. Since the battery includes the cover plate assembly and has the same effects as the cover plate assembly, it will not be elaborated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] Figure 1 Structural schematic diagram of a battery according to an embodiment of the present utility model;

[0026] Figure 2 For Figure 1 Top view of the battery shown;

[0027] Figure 3 For Figure 2 Cross-sectional view in the A-A direction in

[0028] Figure 4 For Figure 3 Partial enlarged view of B in

[0029] Figure 5 For Figure 3 Partial enlarged view of C in

[0030] Figure 6 Structural schematic diagram of a sealing plate according to an embodiment of the present utility model;

[0031] Figure 7 For Figure 6 Top view of the sealing plate shown;

[0032] Figure 8 For Figure 7 Cross-sectional view in the A-A direction in

[0033] Figure 9 For Figure 8 Partial enlarged view of the sealing plate shown;

[0034] Figure 10 For Figure 7 Cross-sectional view in the D-D direction in

[0035] Figure 11 For Figure 6 Structural schematic diagram of the bottom view of the sealing plate shown;

[0036] Figure 12 Structural schematic diagram of the battery according to an embodiment of the present utility model when the sealing plate is not welded and the ear is not welded to the connector;

[0037] Figure 13 For Figure 12 Top view of the battery shown;

[0038] Figure 14 is Figure 13 the sectional view in the A-A direction in

[0039] Figure 15 the structural schematic diagram of the battery in the embodiment of the present utility model when the tab and the connecting member are welded and the sealing plate is not welded

[0040] Figure 16 is Figure 15 the top view of the battery shown in

[0041] Figure 17 is Figure 16 the sectional view in the A-A direction in

[0042] Explanation of reference numerals:

[0043] 1. housing; 2. electrode group; 201. tab; 3. cover plate; 301. welding through hole; 4. terminal; 410. copper part; 420. aluminum part; 401. connection hole; 5. connecting member; 501. connecting member body; 502. welding part; 6. sealing plate; 610. plate body; 620. convex rib; 621. horizontal rib; 622. annular rib; 630. concave rib; 631. straight groove; 632. annular groove; 7. insulating part; 8. sealing ring; 901. upper plastic part; 902. lower plastic part. Specific embodiments

[0044] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are some but not all of the embodiments of the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0045] The following will describe the embodiments of the present utility model in conjunction with Figures 1 to 17 ,

[0046] According to an embodiment of the present utility model, on the one hand, a cover plate assembly is provided, including: a cover plate 3, a pole column 4, a connecting member 5, and a sealing plate 6. The cover plate 3 is provided with a pole column through hole and a welding through hole 301, and the welding through hole 301 is adapted to be disposed opposite to the pole ear 201 on the pole group 2; the pole column 4 is inserted into the pole column through hole and riveted to the cover plate 3, a connection hole 401 is opened on the pole column 4, and the connection hole 401 penetrates the pole column 4 along the extending direction of the center line of the pole column 4; the connecting member 5 includes a connecting member body 501 and a welding portion 502, the welding portion 502 protrudes from the upper surface of the connecting member body 501, the wall thickness of the welding portion 502 is equal to the thickness of the connecting member body 501, and the outer peripheral wall of the welding portion 502 is attached to and welded with the inner peripheral wall of the connection hole 401; the sealing plate 6 is covered in the welding through hole 301 to seal the welding through hole 301, the sealing plate 6 includes a plate body 610 and a convex rib 620, the convex rib 620 protrudes from the upper surface of the plate body 610, the dimension of the convex rib 620 in the up and down direction is H, and the dimension of the plate body 610 in the up and down direction is t, wherein, 0.5t ≤ H ≤ 1.2t. Wherein, the up and down direction refers to Figure 3 and Figure 9 the direction of "up and down" indicated by the arrow in Figure 3 and Figure 9 the surface of the "up" indicated by the arrow in; the center line of the pole column 4 extends in the up and down direction; the upper surface refers to

[0047] Applying the cover plate assembly of this embodiment, by setting that the pole column 4 has a connection hole 401 penetrating in the up and down direction and the connecting piece 5 has a welding part 502 protruding upward, the welding part 502 can extend into the connection hole 401, and the outer peripheral wall of the welding part 502 is welded to the inner wall of the connection hole 401 to realize the electrical connection between the connecting piece 5 and the pole column 4. The structural form in which the welding part 502 extends into the connection hole 401 and cooperates with the connection hole 401 reduces the total size in the up and down direction after the connecting piece 5 and the pole column 4 are combined compared with the traditional matching method in which the upper surface of the connecting piece 5 abuts against the lower surface of the pole column 4, relatively increasing the setting space of other components such as the electrode group 2 inside the battery, so as to improve the utilization rate of the internal space of the battery; by providing welding through holes 301 corresponding to the pole tabs 201 on the electrode group 2 on the cover plate 3, it is convenient for the welding head of the welding equipment to pass through the welding through holes 301 to weld the pole tabs 201 and the connecting piece 5 after the cover plate 3 and the battery case 1 are assembled. The operation is convenient and it is convenient to observe the welding condition of the pole tabs 201 and the connecting piece 5, thereby improving the battery yield. And by setting the sealing plate 6 to cover the welding through holes 301 to realize the sealing of the welding through holes 301 and ensure the sealing performance of the battery. The convex ribs provided on the upper surface of the sealing plate 6 can increase the structural strength of the sealing plate 6 and improve the reliability of the cover plate assembly. At the same time, by setting that the dimension H of the convex rib 620 in the up and down direction and the dimension t of the plate body 610 in the up and down direction satisfy the relational expression 0.5t ≤ H ≤ 1.2t, it can not only ensure that the convex rib 620 has sufficient strengthening effect on the structural strength of the sealing plate 6, but also avoid the excessive weight of the sealing plate 6.

[0048] It should be noted that the sealing plate 6 is composed of a plate body 610 and a convex rib 620 protruding from the upper surface of the plate body 610. The dimension t of the plate body 610 in the up and down direction is the height of the plate body 610, and the dimension H of the convex rib 620 in the up and down direction is the height of the convex rib 620. If H < 0.5t, the height of the convex rib 620 is too small, and the strengthening effect on the strength of the sealing plate 6 is not obvious. The structural strength of the sealing plate 6 is insufficient, resulting in a weak structural strength of the cover plate assembly; if H > 1.2t, the height of the convex rib 620 is too large, the molding is difficult, and more materials are required, resulting in an excessive overall weight of the sealing plate 6, which is not conducive to the improvement of the overall energy density of the battery.

[0049] It should be noted that the pole 4 is riveted to the cover plate 3, which has good stability and high reliability, and avoids the position displacement of the pole 4 during the welding process with the welding portion 502, thereby ensuring the welding quality; the connector 5 is a component of equal wall thickness, which can reduce the material used for the connector 5 and reduce the weight of the connector 5 as much as possible, thereby also improving the energy density of the battery; the welding through hole 301 is arranged opposite to the pole ear 201, and a partial area on the connector 5 corresponds to the pole ear 201, then the partial area is also located in the area opposite to the welding through hole 301, from This makes it convenient for the welding head to extend into the interior of the battery from the welding through hole 301 to perform welding operations on the pole ear 201 and the connector 5; after the pole ear 201 passes through the connector 5 from the bottom to the top, it is bent toward the upper surface of the connector 5, and the bent portion of the pole ear 201 is attached to and welded to the upper surface of the connector 5. Compared with the traditional structure in which the pole ear 201 is first bent and then welded to the lower surface of the connector 5, the total size of the pole ear 201 and the connector 5 along the up and down direction can be reduced, thereby further improving the space utilization inside the battery.

[0050] In one embodiment, the number of the convex ribs 620 is at least two, including a transverse rib 621 and at least one annular rib 622, the annular rib 622 is arranged circumferentially around the transverse rib 621, and two adjacent convex ribs 620 are arranged at intervals. By setting the number of convex ribs 620 to be multiple and the two adjacent convex ribs 620 are arranged at intervals, the multiple convex ribs 620 are distributed on the upper surface of the plate body 610, so that the upper side of the sealing plate 6 forms a concave-convex alternating structure, which can fully increase the structural strength of the sealing plate 6, and by setting multiple convex ribs 620 including a transverse rib 621 and at least one annular rib 622, and the annular rib 622 is arranged circumferentially around the transverse rib 621, the space on the upper surface of the plate body 610 can be fully utilized, and the coverage area of ​​the convex rib 620 on the upper surface of the plate body 610 can be increased as much as possible, thereby further improving the structural strength of the sealing plate 6.

[0051] It should be noted that, since the outer contour of the sealing plate 6 is usually rectangular, the transverse rib 621 is parallel to a longer side of the rectangle, thereby increasing the coverage area of ​​the convex rib 620 on the upper side of the sealing plate 6 .

[0052] In one embodiment, the annular rib 622 is in a racetrack shape, which has a simple structure and is easy to process.

[0053] Preferably, the number of the annular ribs 622 is two, and the two annular ribs 622 are concentrically arranged with a reasonable layout, which can not only improve the strength of the sealing plate 6 but also facilitate molding.

[0054] In one embodiment, the width W1 of the annular rib 622 ranges from 0.3t to 2t. The orthographic projection of the annular rib 622 on the upper surface of the plate body 610 is annular, and the width of the annular rib 622 refers to the width of the ring, that is, the dimension of the annular rib 622 along the Figure 9 "first direction" indicated by the arrow in Figure 9 . If W is less than 0.3t, the width of the annular rib 622 is too small and difficult to form; if W1 is greater than 2t, the width of the annular rib 622 is too large, resulting in a weakening of the strength of the annular rib 622 itself and a poor strengthening effect on the strength of the sealing plate 6. Therefore, by setting the width W1 of the annular rib 622 to range from 0.3t to 2t and correlating the width dimension of the annular rib 622 with the thickness of the plate body 610, it is possible to ensure that the annular rib 622 can be successfully formed and that the annular rib 622 can increase the strength of the sealing plate 6, thereby ensuring the reliability of the cover assembly and the stability of the battery performance.

[0055] In one embodiment, the distance W2 between two adjacent convex ribs 620 ranges from 0.3t to 2t. Wherein, a circular groove recessed relative to the upper surface of the convex rib 620 is formed between two adjacent convex ribs 620, and the distance W2 between two adjacent convex ribs 620 refers to the width of the circular groove, that is, the dimension of the distance between two adjacent convex ribs 620 along the Figure 9 "first direction" indicated by the arrow in Figure 9 . If W2 is less than 0.3t, the interval between two adjacent convex ribs 620 is too small and difficult to form; if W2 is greater than 2t, the interval between two adjacent convex ribs 620 is too large, resulting in a weak strength of the circular groove part and being not conducive to enhancing the strength of the sealing plate 6. Therefore, by setting the distance W2 between two adjacent convex ribs 620 to range from 0.3t to 2t and correlating the interval between the two convex ribs 620 with the thickness of the plate body 610, it is convenient for processing and can ensure the structural strength of the sealing plate 6.

[0056] It should be noted that the convex rib 620 includes a transverse rib 621 and an annular rib 622, and the dimension of the transverse rib 621 and the annular rib 622 in the up-and-down direction is both H. In one embodiment, the dimension H of the annular rib 622 in the up-and-down direction and the width W1 of the annular rib 622 satisfy the relational expression: 0.2 ≤ H / W1 ≤ 4. Wherein, the up-and-down direction refers to Figure 9In the direction indicated by the arrow in the figure, the dimension H of the annular rib 622 in the up and down direction is the height of the annular rib 622. If H / W1 is less than 0.2, the annular rib 622 is flat, the height of the annular rib 622 is too small and the width is too large, and the structural strength of the annular rib 622 itself is relatively low, and the strengthening effect on the strength of the sealing plate 6 is not obvious; if H / W1 is greater than 4, the annular rib 622 is in a narrow and high shape, and it is more difficult to form. Therefore, by setting the ratio of the dimension H of the annular rib 622 in the up and down direction to the width W1 of the annular rib 622 to be within the range of 0.2 to 4, it is possible to ensure that the annular rib 622 can be successfully formed and to ensure the strengthening effect of the annular rib 622 on the strength of the sealing plate 6.

[0057] In one embodiment, the width W1 of the annular rib 622 and the distance W2 between two adjacent convex ribs 620 satisfy the relationship: 0.15 ≤ W1 / W2 ≤ 6.6. If W1 / W2 is less than 0.15, the width of the annular rib 622 is too small relative to the distance between two adjacent convex ribs 620, the annular rib 622 is too narrow, and the structural strength of the annular groove part is weak; if W1 / W2 is greater than 0.15, the width of the annular rib 622 is too large relative to the distance between two adjacent convex ribs 620, the annular rib 622 is too wide, and the strength of the annular rib 622 itself is weak. Therefore, by setting the ratio of the width W1 of the annular rib 622 to the distance W2 between two adjacent convex ribs 620 to be within the range of 0.15 to 6.6, it is possible to ensure that the convex rib 620 has a sufficient strengthening effect on the strength of the sealing plate 6.

[0058] In one embodiment, a concave rib 630 is formed on the lower surface of the sealing plate 6. The concave rib 630 corresponds to the convex rib 620. The concave rib 630 is formed by the depression of a partial area on the lower surface of the sealing plate 6 towards the direction close to the upper surface of the sealing plate 6. The depression depth of the concave rib 630 is less than the dimension t of the plate body 610 in the up and down direction. By forming the concave rib 630 corresponding to the convex rib 620 on the lower surface of the sealing plate 6, the lower surface of the sealing plate 6 has an uneven alternating structure form, which further strengthens the structural strength of the sealing plate 6, and the concave rib 630 corresponds to the convex rib 620 and the depression depth of the concave rib 630 is less than the dimension t of the plate body 610 in the up and down direction, which can avoid having an overly thin area on the sealing plate 6 in the up and down direction and also improve the structural strength of the sealing plate 6.

[0059] Specifically, the concave rib 630 includes a straight groove 631 and an annular groove 632. The straight groove 631 corresponds to the transverse rib 621, the annular groove 632 corresponds to the annular rib 622, and the groove width of the straight groove 631 is less than the width of the transverse rib 621, and the groove width of the annular groove 632 is less than the width W1 of the annular rib 622.

[0060] In one embodiment, the wall thickness T1 of the welding part 502 ≥ 1.5 mm. It should be noted that the connecting piece 5 is a product with a uniform wall thickness. The wall thickness of the welding part 502 and the wall thickness of the connecting piece body 501 are both T1. The wall thickness of the welding part 502 being T1 refers to the thickness of the bottom wall of the welding part 502 in the up and down direction and the wall thickness of its side wall along Figure 4 the "first direction" indicated by the arrow in Figure 4 are both T1. If the wall thickness T1 of the welding part 502 is less than 1.5 mm, the wall thickness is too small and the strength of the welding part 502 is weak. Then, during the welding process of the welding part 502 and the terminal post 4, the welding part 502 may be welded through, or the connection strength between the welding part 502 and the terminal post 4 after welding is poor. Therefore, by setting the wall thickness T1 of the welding part to be greater than or equal to 1.5 mm, it can ensure that the welding part 502 has sufficient welding strength and connection strength, thus ensuring the reliability and safety of the cover plate assembly.

[0061] In one embodiment, the upper surface of the welding part 502 is located below the plane where the upper surface of the terminal post 4 is located. Among them, the upper surface refers to the surface along the Figures 3 to 4 "up" direction indicated by the arrow in Figures 3 to 4 , and the lower surface refers to the surface along the Figures 3 to 4 "down" direction indicated by the arrow in Figures 3 to 4 . It should be noted that during the welding process of the welding part 502 and the terminal post 4, the welding head of the welding equipment performs welding operations from the upper side of the terminal post 4 and welds along the upper side edge of the mating surface between the welding part 502 and the connection hole 401. If the upper surface of the welding part 502 is flush with or protrudes from the upper surface of the terminal post 4, the weld seam formed by welding will protrude from the upper surface of the terminal post 4, affecting the subsequent welding of the terminal post 4 and the Busbar (bus bar), thereby affecting the current-carrying area of the terminal post 4 and resulting in a reduction in the overall performance of the battery. Therefore, by setting the upper surface of the welding part 502 to be located below the plane where the upper surface of the terminal post 4 is located, that is, the upper surface of the welding part 502 is lower than the upper surface of the terminal post 4, it can prevent the weld seam formed after welding the welding part 502 and the terminal post 4 from protruding from the upper surface of the terminal post 4, thereby avoiding affecting the welding of the terminal post 4 and the bus bar and ensuring that the terminal post 4 has a sufficient current-carrying area and improving the battery quality.

[0062] In one embodiment, the connection hole 401 is a circular hole, and the value range of the diameter R0 of the circular hole is: 4.5 mm ≤ R0 ≤ 30 mm, and the wall thickness W0 of the side wall of the pole column 4 ≥ 1.5 mm. The connection hole 401 is a circular hole, which is convenient for processing and has a stable structure. Correspondingly, the projection of the side wall of the pole column 4 on the cross-section perpendicular to the center line of the pole column 4 is a ring, and the wall thickness W0 of the side wall of the pole column 4 is the width of the ring. If the aperture of the connection hole 401 is too small, the contact area with the welding part 502 is too small, affecting the current-carrying capacity; if the aperture of the connection hole 401 is too large and the wall thickness of the side wall of the pole column 4 is too small, the structural strength of the pole column 4 is weak. During the riveting process of the pole column 4 and the cover plate 3, the pole column 4 is prone to deformation, resulting in the connection hole 401 being deformed into a non-circular shape, affecting the fit between the connection hole 401 and the welding part 502. Therefore, by setting the diameter R0 of the connection hole 401 to be within the range of 4.5 mm to 30 mm and the wall thickness W0 of the side wall of the pole column 4 to be greater than or equal to 1.5 mm, it is ensured that when the pole column 4 is riveted to the cover plate 3, the connection hole 401 will not be deformed, thus ensuring the assembly and welding effect between the connection hole 401 and the welding part 502.

[0063] It should be noted that the pole column 4 is riveted on the cover plate 3. After riveting, the pole column 4 includes a riveting rib and riveting heads located at the upper and lower ends of the riveting rib. The outer contour of the riveting head is larger than the contour of the outer peripheral side of the riveting rib. The riveting rib is arranged in the connection hole 401, and the cross-section of the riveting rib is a ring. Then, the wall thickness W0 of the side wall of the pole column 4 refers to the width of the ring formed by the riveting rib. The first riveting head connected to the upper end of the riveting rib is located on the upper side of the cover plate 3, and the second riveting head connected to the lower end of the riveting rib is located on the lower side of the cover plate 3.

[0064] In one embodiment, the circumferential edge of the upper surface of the welding part 502 is configured as a first guiding angle, and the lower edge of the connection hole 401 is configured as a second guiding angle. The second guiding angle cooperates with the first guiding angle and is suitable for guiding the welding part 502 to be inserted into the connection hole 401 from below the pole column 4. The first guiding angle is configured on the edge formed by the intersection of the upper surface of the welding part 502 and its circumferential surface, and the second guiding angle is configured on the edge formed by the intersection of the lower surface of the pole column 4 and the inner wall of the connection hole 401. When the welding part 502 and the pole column 4 are assembled, the welding part 502 is inserted into the connection hole 401 from below the pole column 4. The second guiding angle and the first guiding angle provide guidance for the welding part 502 to move into the connection hole 401, ensuring that the welding part 502 can be smoothly inserted into the connection hole 401, thereby ensuring the smooth fit between the connecting member 5 and the pole column 4 and facilitating the improvement of work efficiency.

[0065] In one embodiment, both the first guiding angle and the second guiding angle are guiding rounded corners, and the radius of the circle where the second guiding angle is located is greater than or equal to 0.2 mm. The rounded corner surface has a smooth transition, good guiding stability, can avoid stress concentration, and by setting the radius of the circle where the second guiding angle is located to be greater than or equal to 0.2 mm, it can avoid insufficient guiding effect due to too small guiding angle, thereby further ensuring that the welding part 502 can be smoothly inserted into the connection hole 401.

[0066] In one embodiment, the value range of the dimension t of the plate body 610 in the up-down direction is: 0.35 mm - 0.8 mm. The dimension of the plate body 610 in the up-down direction is the thickness of the plate body 610. If the thickness of the plate body 610 is less than 0.35 mm, the plate body 610 is too thin and the strength of the sealing plate 6 is weak; if the thickness of the plate body 610 is greater than 0.8 mm, the plate body 610 is too thick, with too much material used, large weight and high cost. Therefore, by setting the thickness t of the plate body to be within the range of 0.35 mm to 0.8 mm, it can not only ensure that the sealing plate 6 has sufficient strength and the reliability of the cover plate assembly, but also can reduce the weight and cost of the sealing plate 6 as much as possible, and can also save the internal space of the battery and improve the space utilization rate, thereby being beneficial to improving the overall energy density of the battery.

[0067] In one embodiment, the value range of the dimension T0 of the cover plate 3 in the up-down direction is 1.5 mm - 2 mm. The dimension of the cover plate 3 in the up-down direction is the thickness of the cover plate 3. If the thickness of the cover plate 3 is less than 1.5 mm, the cover plate 3 is too thin and the strength of the cover plate 3 itself is weak; if the thickness of the cover plate 3 is greater than 2 mm, the cover plate 3 is too thick, with too much material used, large weight and high cost. Therefore, by setting the thickness T0 of the cover plate 3 to be within the range of 1.5 mm to 2 mm, it can not only ensure that the cover plate 3 has sufficient strength and the reliability of the cover plate assembly, but also can reduce the weight and cost of the cover plate 3 as much as possible, thereby being beneficial to improving the overall energy density of the battery.

[0068] In one embodiment, the cover plate assembly further includes: an insulating member 7, and the insulating member 7 is arranged below the sealing plate 6 to prevent the sealing plate 6 from directly contacting the tab 201 or the connecting member 5 and causing a short circuit.

[0069] It should be noted that the terminal post 4 is riveted to the cover plate 3. The cover plate 3 is a polished aluminum plate. The cover plate assembly further includes: a sealing ring 8 sleeved on the outer peripheral side of the riveting rib of the terminal post 4 and located between the terminal post 4 and the cover plate 3 to ensure the sealing between the terminal post 4 and the cover plate 3; an upper plastic part 901 disposed between the first riveting head and the upper surface of the cover plate 3 to ensure insulation between the terminal post 4 and the upper surface of the cover plate 3; a lower plastic part 902 disposed on the lower side of the cover plate 3 to ensure insulation between the cover plate 3 and the electrode group. A part of the structure on the lower plastic part 902 extends between the second riveting head and the lower surface of the cover plate 3 to ensure insulation between the terminal post 4 and the lower surface of the cover plate 3. By providing the sealing ring 8, the upper plastic part 901 and the lower plastic part 902 between the cover plate 3 and the terminal post 4, the insulation and sealing between the terminal post 4 and the cover plate 3 are ensured.

[0070] According to an embodiment of the present invention, on the other hand, a battery is further provided, including: a housing 1, an electrode group 2, and the above-mentioned cover plate assembly. One end of the housing 1 is set as an open end; the electrode group 2 is disposed in the inner cavity of the housing 1, and the electrode group 2 has an electrode tab 201 disposed toward the open end of the housing 1; the cover plate assembly is disposed at the open end of the housing 1 to close the housing 1.

[0071] Specifically, the number of terminal post holes is two, the welding through hole 301 is located between the two terminal post holes, and the terminal post holes and the welding through hole 301 are arranged at intervals; correspondingly, the number of terminal posts 4 is two, one is a positive terminal post and the other is a negative terminal post; the electrode group 2 has two electrode tabs on the side facing the cover plate 3, one is a positive electrode tab and the other is a negative electrode tab. The positive terminal post is connected to the positive electrode tab, and the negative terminal post is connected to the negative electrode tab; the number of connecting members 5 is two, one is connected between the positive terminal post and the positive electrode tab, and the other is connected between the negative terminal post and the negative electrode tab. Among them, the negative terminal post, as Figure 4 shown in, is a copper-aluminum composite terminal post, including a copper part 410 and an aluminum part 420. The copper-aluminum composite terminal post is processed from a copper-aluminum composite plate, that is, the copper part 410 and the aluminum part 420 are closely attached together; the positive terminal post is a single-material aluminum terminal post.

[0072] It should be noted that during the battery assembly process, first, the terminal post 4, the sealing ring 8, the upper plastic part 901, and the lower plastic part 902 are assembled onto the cover plate 3, and then the two connecting members 5 are each assembled and welded to one terminal post 4 to form an integral cover plate assembly; then the electrode group 2 is installed in the housing 1, and then the cover plate assembly is assembled to the open end of the housing 1. At this time, as Figures 12 to 14As shown, the tab 201 on the electrode group 2 extends in the up and down direction, and the tab 201 vertically penetrates the connecting member 5 in the up and down direction; a bending operation is performed on the tab 201 through the welding through hole 301 on the cover plate 3. After the tab 201 is bent by 90°, it fits with the upper surface of the connecting member 5. Then, the welding head of the welding equipment passes through the welding through hole 301 on the cover plate 3 to weld the tab 201 and the connecting member 5, thereby realizing the connection between the tab 201 and the connecting member 5. The structural form after the tab 201 and the connecting member 5 are welded is as shown in Figures 15 to 17 ; Finally, the sealing plate 6 and the insulating member 7 are assembled into one body and then embedded in the welding through hole 301, and the sealing plate 6 is welded to the cover plate 3 to realize the sealing of the welding through hole 301 by the sealing plate 6, completing the assembly of the battery. The structural schematic diagram of the assembled battery is as shown in Figures 1 to 3 . Among them, the welding process between the tab 201 and the connecting member 5 is laser welding or ultrasonic welding, etc.

[0073] Applying the battery of this embodiment improves the space utilization rate inside the battery, reduces the bending process of the connecting member 5, and improves the production efficiency.

[0074] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cover plate assembly, characterized in that: include: The cover plate is provided with a pole through hole and a welding through hole, wherein the welding through hole is suitable for being arranged opposite to the pole ear on the pole group; A pole, which is inserted into the pole through hole and riveted to the cover plate, and a connecting hole is provided on the pole, and the connecting hole passes through the pole along the extension direction of the center line of the pole; A connector, comprising a connector body and a welding portion, wherein the welding portion protrudes from an upper surface of the connector body, the wall thickness of the welding portion is equal to the thickness of the connector body, and the outer peripheral wall of the welding portion is fitted and welded to the inner peripheral wall of the connecting hole; A sealing plate is covered in the welding through hole to close the welding through hole. The sealing plate includes a plate body and a convex rib. The convex rib is protruding from the upper surface of the plate body. The dimension of the convex rib along the up and down direction is H, and the dimension of the plate body along the up and down direction is t, wherein 0.5t≤H≤1.2t.

2. The cover plate assembly according to claim 1, characterized in that: The number of the convex ribs is at least two, including a transverse rib and at least one annular rib. The annular rib is arranged circumferentially around the transverse rib, and two adjacent convex ribs are arranged at intervals.

3. The cover plate assembly according to claim 2, characterized in that: The value range of the width W1 of the annular rib is: 0.3t≤W1≤2t; and / or the value range of the distance W2 between two adjacent convex ribs is: 0.3t≤W2≤2t.

4. The cover plate assembly according to claim 1, characterized in that: The lower surface of the sealing plate is constructed with concave ribs, which correspond to the convex ribs. The concave ribs are formed by a partial area on the lower surface of the sealing plate being recessed toward the upper surface of the sealing plate, and the recessed depth of the concave ribs is smaller than the dimension t of the plate body along the up and down directions.

5. The cover plate assembly according to claim 1, characterized in that: The wall thickness T1 of the welding portion is ≥ 1.5 mm; And / or, the upper surface of the welding portion is located below the plane where the upper surface of the pole is located.

6. The cover plate assembly according to claim 1, characterized in that: The connecting hole is a circular hole, the diameter R0 of the circular hole is in the range of 4.5 mm ≤ R0 ≤ 30 mm, and the wall thickness W0 of the side wall of the pole is ≥ 1.5 mm.

7. The cover plate assembly according to claim 1, characterized in that: The circumferential edge of the upper surface of the welding part is configured as a first guide angle, and the lower side edge of the connecting hole is configured as a second guide angle. The second guide angle cooperates with the first guide angle and is suitable for providing guidance for the welding part to be installed into the connecting hole from the bottom of the pole upward.

8. The cover plate assembly according to claim 7, characterized in that: The first guide angle and the second guide angle are both guide rounded angles, and the radius of the circle where the second guide angle is located is greater than or equal to 0.2 mm.

9. The cover plate assembly according to any one of claims 1 to 8, characterized in that: The dimension t of the plate body in the up-down direction ranges from 0.35 mm to 0.8 mm. And / or, a dimension T0 of the cover plate along the up-down direction ranges from 1.5 mm to 2 mm.

10. A battery, characterized in that: include: A shell, one end of which is configured as an open end; A pole group is arranged in the inner cavity of the shell, and the pole group has a pole ear arranged toward the open end of the shell; The cover plate assembly according to any one of claims 1 to 9 is arranged at the open end of the shell to close the shell.

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