Battery

Abstract

The utility model discloses a battery which comprises an end cover, a shell and a current collecting disc, and the current collecting disc is arranged between the end cover and the shell; the flow collecting disc comprises a flow collecting disc body and a lap joint part, and the lap joint part is connected to the radial outer side of the flow collecting disc body in a surrounding mode and protrudes relative to the flow collecting disc body in the axial direction to form a limiting sinking groove matched with the end cover; in the axial direction, the projection of the lap joint part and the projection of the shell are at least partially overlapped, and the first outer circle face of the lap joint part is attached to the inner wall of the shell; and the end cover and the lap joint part as well as the shell and the lap joint part are in welded connection. Therefore, according to the battery, through lap joint of the current collector and the shell and lap joint of the end cover and the current collector plate, axial and radial three-dimensional positioning can be carried out on the current collector, the shell and the end cover before welding connection, and subsequent welding operation is facilitated. The shell, the current collecting disc and the end cover can be completed in a one-time welding process, and one-time welding can be omitted compared with a structural form that the current collecting disc and the shell are welded firstly and then the shell and the end cover are welded.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries. Background Art

[0002] In the current electrical connection technology of cylindrical batteries, the connection part at one end of the collector plate is connected to the battery cell, and the connection part at the other end is connected to the end cap or pole. The two connections are connected in the form of folding or spring clips. The folding method causes the collector plate to form three layers of material thickness in the axial direction of the battery cell. The overly thick collector plate reduces the height of the battery cell and reduces the battery energy density. The traditional spring-type collector plate and rolling groove sealing structure occupy a huge amount of battery cell capacity. At present, there is a method of lap welding the shell and the collector plate inside the shell, but there are huge risks in the preparation tolerance of the structural parts, tooling fixtures, and welding processes. Utility Model Content

[0003] In view of this, the purpose of the utility model is to provide a battery that can solve the three-dimensional positioning problem among the end cover, the shell and the current collecting plate. At the same time, the shell, the current collecting plate and the end cover can be completed in a single welding process, and visual welding can be achieved.

[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0005] A battery, comprising an end cap, a housing and a current collecting plate, wherein:

[0006] The collecting plate is arranged between the end cover and the shell; the collecting plate comprises a collecting plate body and a lap portion, the lap portion is connected around the radial outer side of the collecting plate body and protrudes relative to the collecting plate body in the axial direction to form a limiting sink groove matched with the end cover;

[0007] Along the axial direction, the projection of the overlap portion at least partially overlaps with the projection of the shell, and the first outer circumferential surface of the overlap portion is in contact with the inner wall of the shell;

[0008] The end cover and the overlapping portion as well as the shell and the overlapping portion are connected by welding.

[0009] Optionally, in the above battery, the first outer circular surface is an outer wall surface of the overlapping portion.

[0010] Optionally, in the above-mentioned battery, the overlapping portion includes a first bending portion extending along the axial direction relative to the collecting plate body, and a second bending portion connected to the free end of the first bending portion and extending radially from the inside to the outside, and the first outer circular surface is the outer wall surface of the first bending portion.

[0011] Optionally, in the above battery, along the axial direction, the overlapping portion, the shell and the end cover are flush.

[0012] Optionally, in the above battery, along the radial direction, the overlapping portion, the shell and the end cover are flush.

[0013] Optionally, in the above battery, the thickness of the overlapped portion disposed between the shell and the end cover is W1;

[0014] The shell and the overlapped portion form a first weld, the overlapped portion and the end cover form a second weld, and the weld widths of the first weld and the second weld are both W2, W2≤2W1;

[0015] Alternatively, the shell, the overlapped portion and the end cover form a third weld, and the weld width of the third weld is W3, W1≤W3≤4W1.

[0016] Optionally, in the above battery, the penetration depths of the first weld, the second weld and the third weld are all h1, 0.2mm≤h1≤1.0mm.

[0017] Optionally, in the above battery, along the axial direction, the overlapping portion is flush with the shell, and along the radial direction, the end cover is flush with the shell.

[0018] Optionally, in the above battery, the overlapped portion and the shell form a fourth weld, the end cover and the shell form a fifth weld, and the penetration depths of the fourth weld and the fifth weld are both h2, 0.2 mm ≤ h2 ≤ 1.0 mm;

[0019] Alternatively, a sixth weld is formed at the connection between the overlap portion, the shell and the end cover, and the penetration depth of the sixth weld is h3, m+0.2mm≤h3≤m+1.0mm, and m is the thickness of the shell at the position of the sixth weld.

[0020] Optionally, in the above battery, along the axial direction, the shell is flush with the end cover, and along the radial direction, the end cover is flush with the overlapping portion.

[0021] Optionally, in the above battery, the overlapped portion and the shell form a seventh weld, the end cover and the shell form an eighth weld, and the penetration depths of the seventh weld and the eighth weld are both h4, 0.2 mm ≤ h4 ≤ 1.0 mm;

[0022] Alternatively, a ninth weld is formed at the connection between the overlap portion, the shell and the end cover, and the penetration depth of the ninth weld is h5, n+0.2mm≤h5≤n+1.0mm, and n is the thickness of the end cover at the position of the ninth weld.

[0023] Optionally, the above battery further comprises a battery cell, which is located in the shell, and along the axial direction, the gap distance between the end cover and the current collecting plate body is G1, 0.1mm≤G1≤3mm;

[0024] G1 ≥ δ1 + δ2 + x;

[0025] δ1 and δ2 are respectively the absolute values ​​of the positive and negative tolerances of the cell height, and x is the height required for the cell to move.

[0026] Optionally, in the above battery, the current collecting plate body includes a first connecting portion, a second connecting portion, and an elastic portion, wherein:

[0027] The radial outer side of the first connection portion is connected to the elastic portion, and the radial outer side of the elastic portion is connected to the radial inner side of the second connection portion;

[0028] A gap between the first connection portion and the second connection portion along the axial direction is greater than 0.

[0029] Optionally, in the above battery, a cross section of the elastic portion along the radial direction is wavy, and a highest point and a lowest point of the cross section are both within the gap between the first connecting portion and the second connecting portion along the axial direction.

[0030] Optionally, in the above battery, a plurality of the elastic parts are arranged along the circumference of the first connecting part, through holes are arranged between adjacent elastic parts, and the corners of the through holes are chamfered;

[0031] The through hole includes a circular arc hole area close to the first connecting portion, and the diameter of the circular arc hole area is d, 0.5mm≤d≤6mm.

[0032] Optionally, in the above battery, the elastic portion includes a plurality of stacked sheet-like members, and the thickness of the sheet-like members is T1, 0.1≤T1≤1mm;

[0033] Alternatively, the elastic portion is a single-layer structure, and its thickness is t3, 0.1 mm ≤ t3 ≤ 3 mm;

[0034] and / or, the thickness t1 of the first connecting portion, 0.1 mm ≤ t1 ≤ 3 mm;

[0035] and / or, the thickness t2 of the second connecting portion, 0.1 mm ≤ t2 ≤ 3 mm

[0036] Optionally, in the above battery, along the circumferential direction, a plurality of the elastic parts are sequentially connected to form a polygon, the radius of the inscribed circle of which is R, 10 mm ≤ R ≤ r,

[0037]

[0038] Among them, R is in mm; Q is the rated capacity of the battery, in Ah; C is the charge and discharge rate, in c; s is the welding safety factor; H is the thickness of the elastic part, in mm; K is the current carrying capacity per unit area of ​​the material, in A / mm 2 ; r is the radius of the winding core of the battery cell, in mm.

[0039] Optionally, in the above battery, a first recessed platform is provided on the outer end surface of the end cover, and along the axial direction, a projection of the second connecting portion at least partially overlaps with a projection of the first recessed platform;

[0040] A tenth weld is provided at the first sinking position, and the penetration depth of the tenth weld is greater than the thickness of the end cover.

[0041] Optionally, in the above battery, the outer end surface of the end cover is provided with notches along a rectangular track, and the notches are provided as chamfers at the corners of the rectangle.

[0042] Optionally, in the above battery, the ratio of the residual thickness of the notch to the thickness of the unnotched portion is proportional to the bursting pressure of the end cover.

[0043] Optionally, in the above battery, the distance between the two long sides of the rectangle is a, the distance between the two short sides is b, the radius of the chamfer of the notch is r1, and the area of ​​the rectangular track is S;

[0044] S=r1 2 (4+π)+ab-4r1(a+b)

[0045] When Q≤50Ah, 100mm2≤S≤300mm2;

[0046] When Q≥50Ah,

[0047]

[0048] Optionally, in the above battery, a reinforcing rib is protruding from the inner end of the end cover.

[0049] Optionally, in the above battery, the battery further includes a battery cell, and the shell includes a cylindrical shell and a square shell.

[0050] It can be seen from the above technical solutions that the battery provided by the utility model can perform axial and radial three-dimensional positioning of the three before welding connection through the overlap of the current collector and the shell, and the overlap of the end cover and the current collector plate, so as to facilitate subsequent welding operations. The shell, the current collector plate and the end cover can be completed in one welding process, which can save one welding compared to the structural form of welding the current collector plate and the shell first, and then welding the shell and the end cover; in addition, the outer lap welding is less difficult than the internal lap welding and the penetration welding process, and can realize visual welding, which can avoid the problem of position offset affecting the welding quality during the welding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0052] Figure 1 A schematic diagram of the structure of a current collecting plate provided in an embodiment of the utility model;

[0053] Figure 2 A top view of a current collecting plate provided in an embodiment of the utility model;

[0054] Figure 3 A cross-sectional view of AA is provided for an embodiment of the utility model;

[0055] Figure 4 A cross-sectional view of a battery provided in Example 1 of the utility model;

[0056] Figure 5 The embodiment of the utility model provides Figure 4 A partial enlarged view of the

[0057] Figure 6 A cross-sectional view of a battery provided in Example 2 of the utility model;

[0058] Figure 7 The embodiment of the utility model provides Figure 6 A partial enlarged view of the

[0059] Figure 8 A cross-sectional view of a battery provided in Embodiment 3 of the present utility model;

[0060] Fig. 9 The embodiment of the utility model provides Figure 8 A partial enlarged view of the

[0061] Fig.10A cross-sectional view of a battery provided in Embodiment 4 of the present utility model;

[0062] Fig.11 The embodiment of the utility model provides Fig.10 A partial enlarged view of the

[0063] Fig.12 Schematic diagram of welding structure provided in the first and fourth embodiments of the present invention Figure 1 ;

[0064] Fig.13 Schematic diagram of welding structure provided in the first and fourth embodiments of the present invention Figure 2 ;

[0065] Fig.14 A schematic diagram of the welding structure provided in the second embodiment of the utility model;

[0066] Fig.15 A schematic diagram of the welding structure provided by the third embodiment of the utility model;

[0067] Fig.16 A structural schematic diagram of welding at the first sinking position provided by an embodiment of the utility model;

[0068] Fig.17 A top view of the end cap provided in the embodiment of the utility model;

[0069] Fig.18 The utility model provides Fig.13 Schematic diagram of welding trajectory Figure 1 ;

[0070] Fig.19 The utility model provides Fig.13 Schematic diagram of welding trajectory Figure 2 .

[0071] in:

[0072] 1-end cover, 11-first sink, 12-notch, 13-liquid injection hole, 14-first reinforcing rib, 15-second reinforcing rib, 16-second sink, 2-shell, 3-collecting plate,

[0073] 31-collecting disc body, 311-first connecting portion, 3111-second through hole, 312-second connecting portion, 313-elastic portion,

[0074] 32-lap joint, 321-first outer circumferential surface, 322-first bending portion, 323-second bending portion, 33-through hole,

[0075] 4-Battery cells. DETAILED DESCRIPTION

[0076] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0077] In the description of the utility model, it should be noted that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the utility model product is usually placed when in use, and are only for the convenience of describing the utility model 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 a limitation on the utility model. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0078] like Figures 1 to 19 As shown, an embodiment of the utility model provides a battery.

[0079] First, the battery comprises an end cover 1, a shell 2 and a current collecting plate 3, wherein the current collecting plate 3 is arranged between the end cover 1 and the shell 2; the current collecting plate 3 comprises a current collecting plate body 31 and an overlap portion 32, the overlap portion 32 is connected to the radial outer side of the current collecting plate body 31 in a surrounding manner, and protrudes relative to the current collecting plate body 31 in the axial direction to form a limiting groove matched with the end cover 1, and the end cover 1 is arranged in the groove, which can limit the end cover 1 axially and radially; along the axial direction, the projection of the overlap portion 32 overlaps with the projection of the shell 2 at least partially, so that the overlap portion 32 can overlap on the shell 2, which can limit the current collecting plate 3 axially, and the first outer cylindrical surface 321 of the overlap portion 32 fits with the inner wall of the shell 2, which can limit the current collecting plate 3 radially; the end cover 1 and the overlap portion 32 and the shell 2 and the overlap portion 32 are welded and connected, and the axial and radial positions of the end cover 1, the shell 2 and the current collecting plate 3 are mutually limited, which is convenient for the welding operation among the three.

[0080] It can be seen that the battery provided by the embodiment of the utility model can perform axial and radial three-dimensional positioning of the three before welding connection through the overlap of the current collector and the shell 2, and the overlap of the end cover 1 and the current collecting plate 3, so as to facilitate the subsequent welding operation. The shell, the current collecting plate and the end cover can be completed in one welding process, which can save one welding compared to the structural form of welding the current collecting plate and the shell first, and then welding the shell and the end cover; in addition, the outer lap welding is less difficult than the internal lap welding and the penetration welding process, and can realize visual welding, which can avoid the problem of position deviation affecting the welding quality during the welding process. It is convenient for subsequent manual visual inspection and other work.

[0081] Example 1

[0082] For specific implementation, see Figure 5 , Figure 7 , Fig. 9 , the first outer circular surface 321 is the outer wall surface of the overlap portion 32, and the shell 2 is provided with a receiving groove capable of placing at least part of the overlap portion 32, so that the overlap portion 32 can overlap the shell 2. It should be noted that, in order to ensure that the projection of the overlap portion 32 and the projection of the shell 2 at least partially overlap in the axial direction, the inner diameter of the overlap portion 32 at the position where the inner wall of the shell 2 is attached is larger than the inner diameter of the shell 2 at the position where the overlap portion 32 is not attached, so that the shell 2 forms a step surface at the position where the overlap portion 32 is attached, so that the overlap portion 32 can overlap the step surface, and the axial position of the shell 2 and the overlap portion 32 is limited. The step surface can be formed by making the outer diameter of the shell 2 equal and the shell 2 partially thinned; it can also be achieved by keeping the thickness of the shell 2 unchanged and bending at the step surface position. In this case, the thickness of the shell 2 remains unchanged, and the outer diameter of the shell 2 at the position where the overlap portion 32 is attached to the inner wall of the shell 2 is larger than the outer diameter of the shell 2 at the position where the overlap portion 32 is attached. However, it is not limited thereto. As long as the shell 2 can form a stepped surface overlapping with the overlapping portion 32 , the specific structure of the shell 2 can be specifically designed by those skilled in the art according to actual needs.

[0083] For specific implementation, see Figure 8 and Fig. 9 Along the axial direction, the overlap portion 32, the shell 2 and the end cover 1 are flush. It should be noted that the three are flush along the axial direction, that is, the end surface heights of the three are the same in the axial direction, and the shell 2, the collecting plate 3 and the bottom surface of the end cover 1 are in the same plane, ensuring that the outer end surface structure is neat, which is not only convenient for welding connection, but also can make the battery appearance more neat.

[0084] For specific implementation, see Fig.12, the thickness of the overlap portion 32 placed between the shell 2 and the end cover 1 is W1; the shell 2 and the overlap portion 32 form a first weld, the overlap portion 32 and the end cover 1 form a second weld, and the molten width of the first weld and the second weld are both W2, W2≤2W1; it should be noted that the first weld and the second weld are welded by laser welding or composite welding, but not limited to this, and the technical personnel in this field can make specific designs for the specific welding method according to actual needs. It should be noted that the specific position of the first weld is at the contact position of the shell 2 and the overlap portion 32 where visual welding can be achieved, and the specific position of the second weld is at the contact position of the overlap portion 32 and the end cover 1 where visual welding can be achieved. See for details. Figure 5 , along the axial direction, the overlap portion 32, the shell 2 and the end cover 1 are flush, and the first weld and the second weld are both located in the plane where the outer end surface of the end cover 1 is located.

[0085] Alternatively, see Fig.13 The shell 2, the overlapped portion 32 and the end cover 1 form a third weld, and the weld width of the third weld is W3, W1≤W3≤4W1. When welding the third weld, the welding swing amount needs to be increased, and the center of the weld width coincides with the center of the weld to obtain the best welding effect. In addition, the welding trajectory of the third weld is sinusoidal (see Fig.19 ) or spiral (see Fig.18 ); and, the welding adopts laser welding or composite welding. However, it is not limited to this. The welding trajectory of the third weld and the specific welding method can be specifically designed by those skilled in the art according to actual needs. It should be noted that the specific position of the third weld is at a position where visual welding can be achieved, and the shell 2, the overlap portion 32 and the end cover 1 are connected together by one welding. Along the axial direction, the overlap portion 32, the shell 2 and the end cover 1 are flush, and the third weld is located in the plane where the outer end surface of the end cover 1 is located.

[0086] However, in specific implementation, the penetration depths of the first weld, the second weld and the third weld are all h1, 0.2mm≤h1≤1.0mm, which can maintain the strength of the material and the aesthetic appearance, and can meet the welding strength requirements.

[0087] In a specific implementation, it also includes a battery cell 4, which is located in the housing 2. In the axial direction, the gap distance between the end cover 1 and the collector plate body 31 is G1, 0.1mm≤G1≤3mm; G1≥δ1+δ2+x; δ1 and δ2 are respectively the absolute values ​​of the positive and negative tolerances of the height of the battery cell 4, and x is the height required for the movement of the battery cell 4. It can ensure that during the use of the battery, the battery cell 4 can move axially within a reasonable range without affecting the performance of the battery, thereby ensuring the safety of the battery.

[0088] In specific implementation, the collector body 31 includes a first connection part 311, a second connection part 312, and an elastic part 313, wherein: the radial outer side of the first connection part 311 is connected to the elastic part 313, and the radial outer side of the elastic part 313 is connected to the radial inner side of the second connection part 312; the gap between the first connection part 311 and the second connection part 312 along the axial direction is greater than 0. That is, by setting the elastic part 313, the relative movement of the first connection part 311 and the second connection part 312 along the axial direction can be achieved. It can improve the safety and stability of the battery. It should be noted that the first connection part 311, the second connection part 312, and the elastic part 313 of the collector 3 can be an integrally formed structural part, or they can be partially or completely separate parts connected by welding or other methods.

[0089] During specific implementation, the cross section of the elastic part 313 along the radial direction is wavy, and the highest and lowest points of the cross section are both within the gap range of the first connecting part 311 and the second connecting part 312 along the axial direction. It can avoid the highest point of the elastic part 313 being higher than the first connecting part 311, avoid cold welding with the battery cell 4, and avoid the lowest point of the elastic part 313 from interfering with the end cover 1 when entering the shell 2. The cross section of the elastic part 313 is wavy to avoid interference or excessive pressure on the battery cell 4. It should be noted that the wavy cross section can have one convex point and one concave point, or multiple points, but is not limited to this. The cross section of the elastic part along the radial direction can also be linear, and those skilled in the art can make specific designs according to actual needs. The purpose is to form a bending structure along the axial and radial directions to achieve the axial movement of the battery cell 4 and compensate for the tolerance of the battery cell 4.

[0090] In specific implementation, multiple elastic parts 313 are arranged along the circumference of the first connection part 311, and through holes 33 are arranged between adjacent elastic parts 313, and the corners of the through holes 33 are chamfered; the through holes 33 include an arc hole area close to the first connection part 311 (that is, the intersection of the through hole 33 and the first connection part 311 is a rounded corner), and the arc hole area ensures that the cross-sectional area of ​​the connection between the first connection part 311 and the elastic part 313 meets the overcurrent requirement. The diameter of the arc hole area is d, 0.5mm≤d≤6mm. Make the area of ​​the first connection part 311 large enough to meet the overcurrent area given by the battery cell 4 and reduce the internal resistance of the battery cell 4. For the battery cell 4 with a diameter of 46mm, its overcurrent capacity is 6C. It should be noted that the through hole 33 can be in the form of an arc or a combination of an arc and a straight line segment. In addition, the arc hole area can disperse the current, avoid current concentration, and heat at the tip.

[0091] In a specific implementation, the elastic part 313 includes a plurality of stacked sheet-like components, the thickness of the sheet-like components is T1, 0.1≤T1≤1mm; or, the elastic part 313 is a single-layer structure, and its thickness is t3, 0.1mm≤t3≤3mm; and / or, the thickness t1 of the first connection part 311 is 0.1mm≤t1≤3mm; and / or, the thickness t2 of the second connection part 312 is 0.1mm≤t2≤3mm. It should be noted that the elastic part 313 is thinner, smaller in width or more plastic in material than the first connection part 311 and the second connection part 312 to achieve the bending of the elastic part 313 in the radial or axial direction and can withstand multiple folding and reciprocating rotation due to changes in air pressure when the battery is used. The first connection part 311, the second connection part 312 and the elastic part 313 can be made of the same material. Preferably, the first connection part 311 and the second connection part 312 are made of the same metal material as the correspondingly connected battery cell 4 tabs. The elastic part 313, the first connecting part 312, and the second connecting part 313 all adopt a plurality of stacked sheet-like components, and the welding positions of the three are at the junction of the elastic part 313 and the first connecting part 311 and the connection junction of the elastic part 313 and the second connecting part 312. Alternatively, the elastic part 313, the first connecting part 312, and the second connecting part 313 all adopt a single-layer structure. Alternatively, the elastic part 313 is a plurality of stacked sheet-like components, the first connecting part 312, and the second connecting part 313 all adopt a single-layer structure, and the welding positions of the three are at the junction of the elastic part 313 and the first connecting part 311 and the connection junction of the elastic part 313 and the second connecting part 312. The welding form of the welding positions of the three is molecular diffusion welding but is not limited thereto. The welding form can be specifically designed by those skilled in the art according to actual needs.

[0092] In a specific implementation, along the circumferential direction, a plurality of elastic parts 313 are sequentially connected to form a polygon, and the radius of the inscribed circle is R, 10 mm ≤ R ≤ r.

[0093]

[0094] Among them, R is in mm; Q is the rated capacity of the battery, in Ah, in the range of 10≤Q≤200Ah; C is the charge and discharge rate, in the range of 0.5≤C≤20; s is the welding safety factor, in the range of 1≤s≤10; H is the thickness of the elastic part 313, in mm, in the range of 0.1≤H≤5mm; K is the current carrying capacity per unit area of ​​the material, in A / mm 2 , the range is 0.5≤K≤10A / mm 2 ; r is the radius of the winding core of the battery cell 4, in mm, and ranges from 20≤r≤200mm.

[0095] In specific implementation, the outer end surface of the end cover 1 is provided with a first sinking platform 11, and the projection of the second connection portion 312 and the projection of the first sinking platform 11 at least partially overlap in the axial direction; a tenth weld is provided at the position of the first sinking platform 11, and the penetration of the tenth weld is greater than the thickness of the end cover 1. That is, the first sinking platform 11 corresponds to the annular surface of the second connection portion 312 of the current collecting plate 3, and the end cover 1 and the current collecting plate 3 are welded by penetration welding at the first sinking platform 11, which can not only make the structure more stable but also further expand the flow area.

[0096] In specific implementation, the outer end surface of the end cap 1 is provided with notches 12 along a rectangular track, and the notches 12 are provided as chamfers at the rectangular corners. Under the premise of meeting the industry use standards, the thickness H1 of the end cap is 0.1mm≤H1≤2mm, preferably 0.3mm, 0.5mm, 0.8mm.

[0097] In a specific implementation, the ratio of the residual thickness of the notch 12 to the thickness of the unnotch portion is proportional to the bursting pressure of the explosion-proof disk. The residual thickness of the notch 12 is H2, and 0.1 mm ≤ H2 ≤ H1.

[0098] In a specific implementation, the distance between the two long sides of the rectangle is a, the distance between the two short sides is b, the radius of the chamfer of the notch 12 is r1, 2r1<a, the larger the r1, the more the explosion-proof disk tends to be a runway-type explosion-proof disk, and the less obvious the explosion form; the area of ​​the rectangular track is S;

[0099] S=r1 2 (4+π)+ab-4r1(a+b)

[0100] When Q≤50Ah, 100mm 2 ≤S≤300mm 2 ;

[0101] When Q≥50Ah,

[0102]

[0103] Satisfying the above relationship, when the explosion pressure is reached, there is sufficient exhaust area, and

[0104]

[0105] The larger the aspect ratio, the smaller the blasting speed.

[0106] In specific implementation, the end cap 1 is provided with a straight tearing section, and the straight tearing state of the two opposite sides of the end cap 1 after the explosion is consistent, the tearing direction is parallel to the straight line, and the bending line is parallel to the edge of the straight tearing section for winding, and finally forms a winding shape, rather than a folded shape in the straight tearing section, after the explosion, the end cap 1 has a morphology. The morphology of the end cap 1 after the explosion is more controllable, and has less impact on the gas discharge after the explosion.

[0107] In specific implementation, the end cover 1 is provided with reinforcing ribs, which can improve the structural strength and rigidity of the end cover 1.

[0108] In a specific implementation, the reinforcing ribs include a first reinforcing rib 14 and a second reinforcing rib 15, the inner diameter of the first reinforcing rib 14 is larger than the inner diameter of the second reinforcing rib 15, and the end of the first reinforcing rib 14 away from the end cover 1 abuts against the second connecting portion 312. The first reinforcing rib 14 and the second reinforcing rib 15 form a second sink 16 with the end cover 1. It should be noted that, radially, the reinforcing ribs may be located outside the explosion-proof notch 12; or the reinforcing ribs may be located both outside the explosion-proof notch 12 and inside the explosion-proof notch 12. And the number of internal and external reinforcing ribs may be 0, 1, 2 or more, and those skilled in the art may make specific designs according to actual needs. However, the main role is played by the reinforcing ribs located outside the notch 12 in the radial direction.

[0109] In specific implementation, the first connection portion 311 of the current collecting plate 3 coincides with the central axis of the battery cell 4, and the first connection portion 311 is welded to the end face of the battery cell 4 near one pole of the end cover 1, and the welding connection method includes but is not limited to laser welding, and the welding track includes but is not limited to multiple radial long and short strips and multiple circular rings. The first connection portion 311 is provided with a second through hole 3111, and the center line of the second through hole 3111 coincides with the center line of the current collecting plate 3, and coincides with the center line of the injection hole 13 of the end cover 1, so as to facilitate uniform injection.

[0110] During specific implementation, the central axis of the second connecting part 312 coincides with the central axis of the end cover 1, and the second connecting part 312 is connected to the shell 2 and the end cover 1 by the overlap part 32, which can be a welding connection. The connection method can be but is not limited to laser welding. Technical personnel in this field can make specific designs according to actual needs.

[0111] In a specific implementation, the battery also includes a battery cell, and the shell includes a cylindrical shell and a square shell; that is, the collecting plate 3 and the connection method between the collecting plate 3 and the battery cell 4 and the end cover 1 are suitable for cylindrical full-pole ear lithium-ion batteries, and are also suitable for square full-pole ear lithium-ion batteries, especially single-pole square batteries.

[0112] Example 2

[0113] like Figure 6 , Figure 7 , Fig.14 As shown, the second embodiment of the present invention provides a battery. The difference between the second embodiment of the present invention and the first embodiment is that:

[0114] For specific implementation, see Fig.14 , along the axial direction, the overlap portion 32 is flush with the shell 2, and along the radial direction, the end cover 1 is flush with the shell 2. That is, along the axial direction, the overlap portion 32 and the shell 2 have the same height, and along the radial direction, the outer diameters of the end cover 1 and the shell 2 are the same.

[0115] During specific implementation, the overlapping portion 32 and the shell 2 form a fourth weld, and the end cover 1 and the shell 2 form a fifth weld. The penetration depth of the fourth weld and the fifth weld are both h2, 0.2mm≤h2≤1.0mm; through at least two welding processes, the first welding process welds the overlapping portion 32 and the shell 2 closely attached welding surface to form the fourth weld, and then the end cover 1 is positioned, and the shell 2 and the end cover 1 closely attached welding surface are welded to form the fifth weld, and laser welding or composite welding is used, but it is not limited to this. The specific welding method of the fourth weld and the fifth weld can be specifically designed by technical personnel in this field according to actual needs. It should be noted that the specific position of the fourth weld is at the contact position of the shell 2 and the overlapping portion 32 where visual welding can be achieved, and the specific position of the fifth weld is at the contact position of the shell 2 and the end cover 1 where visual welding can be achieved. See for details. Figure 7 The fourth weld is located on the plane of the end surface of the shell close to the end cover 1, and the fifth weld is located on the outer side of the shell.

[0116] Alternatively, a sixth weld is formed at the connection between the lap joint 32, the shell 2 and the end cover 1, and the penetration depth of the sixth weld is h3, m+0.2mm≤h3≤m+1.0mm, and m is the thickness of the shell 2 at the position of the sixth weld. The welding power of the shell 2 and the end cover 1 is increased to achieve penetration welding, and the end cover 1, the shell 2 and the lap joint 32 are welded together. It should be noted that the sixth weld is located on the outer side of the shell 2, at the contact position between the shell 2 and the end cover 1.

[0117] Exemplary Embodiment Three

[0118] like Figure 8 , Fig. 9 , Fig.15 As shown, the third embodiment of the present invention provides a battery. The difference between the third embodiment of the present invention and the first embodiment is that:

[0119] For specific implementation, see Fig.15 , along the axial direction, the shell 2 is flush with the end cover 1, and along the radial direction, the end cover 1 is flush with the overlap 32. That is, along the axial direction, the shell 2 and the end cover 1 are equal in height, and along the radial direction, the end cover 1 and the overlap 32 have the same outer diameter.

[0120] During specific implementation, the overlap portion 32 and the shell 2 form the seventh weld, and the end cover 1 and the shell 2 form the eighth weld. The penetration depth of the seventh weld and the eighth weld are both h4, 0.2mm≤h4≤1.0mm; through at least two welding processes, the first welding process welds the overlap portion 32 and the shell 2 closely attached welding surface to form the seventh weld, and then the end cover 1 is positioned, and the shell 2 and the end cover 1 closely attached welding surface are welded to form the eighth weld, and laser welding or composite welding is used, but it is not limited to this. The specific welding method of the seventh weld and the eighth weld can be specifically designed by technical personnel in this field according to actual needs. It should be noted that the specific position of the seventh weld is at the contact position of the overlap portion 32 and the shell 2 where visual welding can be achieved, and the specific position of the eighth weld is at the contact position of the shell 2 and the end cover 1 where visual welding can be achieved. See for details. Fig. 9 The seventh weld is located on the plane where the end face of the overlapped portion is away from the battery core 4 , and the eighth weld is located on the plane where the outer end face of the end cover 1 is located.

[0121] Alternatively, a ninth weld is formed at the connection between the lap joint 32, the shell 2 and the end cover 1, and the penetration depth of the ninth weld is h5, n+0.2mm≤h5≤n+1.0mm, and n is the thickness of the end cover 1 at the position of the ninth weld. The welding power of the shell 2 and the end cover 1 is increased to achieve penetration welding, and the end cover 1, the shell 2 and the lap joint 32 are welded together. It should be noted that the ninth weld is located in the plane where the outer end surface of the end cover 1 is located, and the contact position between the shell 2 and the end cover 1.

[0122] Example 4

[0123] like Fig.10 , Fig.11 As shown, the fourth embodiment of the utility model provides a battery. The difference between the fourth embodiment of the utility model and the first embodiment is that:

[0124] For specific implementation, see Fig.10 The overlapping portion 32 includes a first bending portion 322 extending axially relative to the collecting disc body 31, and a second bending portion 323 connected to the free end of the first bending portion 322 and extending radially from the inside to the outside. The first outer circular surface 321 is the outer wall surface of the first bending portion 322, that is, the radial cross-section of the overlapping portion 32 is L-shaped, and the second bending portion 323 can be placed on the outer end surface of the shell 2 so that the overlapping portion 32 can overlap the shell 2 and can axially limit the collecting disc 3; the outer wall surface of the first bending portion 322 is in contact with the inner wall of the shell 2, which can radially limit the collecting disc 3.

[0125] In specific implementation, the overlap portion 32, the shell 2 and the end cover 1 are flush along the radial direction. It should be noted that the flushness along the radial direction means that the outer diameters of the three are equal and the circumferential outer surface of the battery is flush, which is not only convenient for welding connection, but also can make the battery appearance more neat.

[0126] For specific implementation, see Fig.11 The first weld and the second weld are both located on the outer side of the shell 2.

[0127] For specific implementation, see Fig.13 The third weld is located on the outer side of the shell 2. The specific position of the third weld is at a position where visible welding can be achieved, and the shell 2, the overlap portion 32 and the end cover 1 are connected together by one welding.

[0128] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0129] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0130] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery, characterized in that: It comprises an end cover (1), a shell (2) and a current collecting plate (3), wherein: The collecting plate (3) is arranged between the end cover (1) and the shell (2); the collecting plate (3) comprises a collecting plate body (31) and an overlapping portion (32); the overlapping portion (32) is connected to the radial outer side of the collecting plate body (31) in a surrounding manner and protrudes relative to the collecting plate body (31) in the axial direction to form a limiting sink groove that cooperates with the end cover (1); Along the axial direction, the projection of the overlapping portion (32) at least partially overlaps with the projection of the shell (2), and the first outer circular surface (321) of the overlapping portion (32) is in contact with the inner wall of the shell (2); The end cover (1) and the overlapping portion (32) as well as the shell (2) and the overlapping portion (32) are connected by welding.

2. The battery according to claim 1, characterized in that: The first outer circular surface (321) is the outer wall surface of the overlapping portion (32).

3. The battery according to claim 1, characterized in that: The overlapping portion (32) comprises a first bent portion (322) extending along the axial direction relative to the collecting plate body (31), and a second bent portion (323) connected to the free end of the first bent portion and extending radially from the inside to the outside, and the first outer circular surface (321) is the outer wall surface of the first bent portion.

4. The battery according to claim 2, characterized in that Along the axial direction, the overlapping portion (32), the shell (2) and the end cover (1) are flush.

5. The battery according to claim 3, characterized in that: Along the radial direction, the overlapping portion (32), the shell (2) and the end cover (1) are flush.

6. The battery according to claim 2 or 3, characterized in that: The thickness of the overlapping portion (32) disposed between the shell (2) and the end cover (1) is W1; The shell (2) and the overlapped portion (32) form a first weld, the overlapped portion (32) and the end cover (1) form a second weld, and the weld widths of the first weld and the second weld are both W2, W2≤2W1; Alternatively, the shell (2), the overlapping portion (32) and the end cover (1) form a third weld, and the weld width of the third weld is W3, W1≤W3≤4W1.

7. The battery according to claim 6, characterized in that The penetration depths of the first weld, the second weld and the third weld are all h1, 0.2mm≤h1≤1.0mm.

8. The battery according to claim 2, characterized in that Along the axial direction, the overlap portion (32) is flush with the shell (2), and along the radial direction, the end cover (1) is flush with the shell (2).

9. The battery according to claim 8, characterized in that The overlapped portion (32) and the shell (2) form a fourth weld, the end cover (1) and the shell (2) form a fifth weld, the penetration depths of the fourth weld and the fifth weld are both h2, 0.2 mm ≤ h2 ≤ 1.0 mm; Alternatively, a sixth weld is formed at the connection between the overlap portion (32), the shell (2) and the end cover (1), and the penetration depth of the sixth weld is h3, m+0.2mm≤h3≤m+1.0mm, and m is the thickness of the shell (2) at the position of the sixth weld.

10. The battery according to claim 2, characterized in that Along the axial direction, the housing (2) is flush with the end cover (1), and along the radial direction, the end cover (1) is flush with the overlap portion (32).

11. The battery according to claim 10, characterized in that The overlapping portion (32) and the shell (2) form a seventh weld, the end cover (1) and the shell (2) form an eighth weld, and the penetration depths of the seventh weld and the eighth weld are both h4, 0.2 mm ≤ h4 ≤ 1.0 mm; Alternatively, a ninth weld is formed at the connection between the overlap portion (32), the shell (2) and the end cover (1), and the penetration depth of the ninth weld is h5, n+0.2mm≤h5≤n+1.0mm, and n is the thickness of the end cover (1) at the position of the ninth weld.

12. The battery according to claim 1, characterized in that It also includes an electric core (4), which is located in the housing (2), and along the axial direction, the gap distance between the end cover (1) and the current collecting plate body (31) is G1, 0.1mm≤G1≤3mm; G1 ≥ δ1 + δ2 + x; δ1 and δ2 are respectively the absolute values ​​of the positive and negative tolerances of the height of the battery cell (4), and x is the height required for the battery cell (4) to move.

13. The battery according to claim 12, characterized in that The collecting plate body (31) comprises a first connecting portion (311), a second connecting portion (312), and an elastic portion (313), wherein: The radial outer side of the first connection portion (311) is connected to the elastic portion (313), and the radial outer side of the elastic portion (313) is connected to the radial inner side of the second connection portion (312); A gap between the first connecting portion (311) and the second connecting portion (312) along the axial direction is greater than 0.

14. The battery according to claim 13, characterized in that The cross section of the elastic portion (313) along the radial direction is wave-shaped, and the highest point and the lowest point of the cross section are both within the gap range between the first connecting portion (311) and the second connecting portion (312) along the axial direction.

15. The battery according to claim 13, characterized in that A plurality of the elastic parts (313) are arranged along the circumference of the first connecting part (311), through holes (33) are arranged between adjacent elastic parts (313), and the corners of the through holes (33) are chamfered; The through hole (33) comprises a circular arc hole area close to the first connecting portion (311), and the diameter of the circular arc hole area is d, 0.5 mm≤d≤6 mm.

16. The battery according to claim 13, characterized in that The elastic part (313) comprises a plurality of stacked sheet-like components, the thickness of the sheet-like components being T1, 0.1≤T1≤1mm; Alternatively, the elastic portion (313) is a single-layer structure, and its thickness is t3, 0.1mm≤t3≤3mm; and / or, the thickness t1 of the first connecting portion (311) is 0.1 mm ≤ t1 ≤ 3 mm; And / or, the thickness t2 of the second connecting portion (312) is 0.1mm≤t2≤3mm.

17. The battery according to claim 13, characterized in that Along the circumferential direction, a plurality of the elastic parts (313) are sequentially connected to form a polygon, the radius of the inscribed circle of which is R, 10 mm ≤ R ≤ r, Wherein, R is in mm; Q is the rated capacity of the battery in Ah; C is the charge and discharge rate in c; s is the welding safety factor; H is the thickness of the elastic part (313) in mm; K is the current carrying capacity per unit area of ​​the material in A / mm 2 ; r is the radius of the winding core of the battery cell (4), in mm.

18. The battery according to claim 13, characterized in that The outer end surface of the end cover (1) is provided with a first sinking platform (11), and along the axial direction, the projection of the second connecting portion (312) at least partially overlaps with the projection of the first sinking platform (11); A tenth weld is provided at the position of the first sink (11), and the penetration depth of the tenth weld is greater than the thickness of the end cover (1).

19. The battery according to claim 1, characterized in that The outer end surface of the end cover (1) is provided with a notch (12) along a rectangular track, and the notch (12) is provided as a chamfer at a rectangular corner.

20. The battery according to claim 19, characterized in that The ratio of the residual thickness of the notch (12) to the thickness of the unnotch portion is proportional to the bursting pressure of the end cover.

21. The battery according to claim 19, characterized in that The distance between the two long sides of the rectangle is a, the distance between the two short sides is b, the radius of the chamfer of the notch is r1, and the area of ​​the rectangular track is S; S=r1 2 (4+π)+ab-4r1(a+b) When Q≤50Ah, 100mm 2 ≤S≤300mm 2 ; When Q≥50Ah, 22. The battery according to claim 13, characterized in that The inner end of the end cover (1) is protrudingly provided with a reinforcing rib.

23. The battery according to claim 1, characterized in that The battery further comprises a battery cell, and the shell comprises a cylindrical shell and a square shell.

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