Battery module and battery pack

Abstract

The utility model provides a battery module and a battery pack, the battery module comprises a battery cell, the battery module comprises a pole, and the first surface of the pole is connected with a fastener; the edge of the first surface in the first direction is defined as a first edge, and the minimum spacing distance between the edge of the fastener and the first edge is a; the length of the first surface in the first direction is not greater than that in the second direction, and the second direction intersects with the first direction; the module bar is welded with the first surface of the pole, and a welding track is arranged around the fastener; when a is smaller than 4 mm, the welding track comprises a sectional type welding line track; and when a is greater than or equal to 4mm, the welding track comprises a continuous welding line track. According to the battery module and the battery pack provided by the invention, matched welding tracks can be arranged on the first surfaces corresponding to the first surfaces with different sizes, so that reliable welding between the pole and the module bar is realized, the structural design flexibility of the battery cell is effectively improved, and the design of the battery cell and the pole is not limited by the welding tracks any more.

Description

Technical Field

[0001] The present application relates to the technical field of power batteries, and in particular to a battery module and a battery pack. Background Art

[0002] The battery module includes multiple battery cells. In order to achieve electrical connection between adjacent battery cells, module bars are used to connect the poles of the adjacent battery cells. The module bars and poles are usually connected by welding. The existing welding tracks usually formed on the poles of the battery cells are continuous annular tracks. In order to make the surface of the pole meet the process requirements for setting the existing welding tracks, the surface size of the pole can only be designed to be larger, which limits the structural design of the battery cells.

[0003] Therefore, how to improve the structural design flexibility of battery cells by improving the existing welding tracks has become an urgent problem to be solved. Utility Model Content

[0004] In view of this, the purpose of the present application is to provide a battery module and a battery pack.

[0005] Based on the above-mentioned purpose, the first aspect of the present application provides a battery module, including: a battery cell, including a pole, a first surface of the pole is connected to a fastener; the edge of the first surface in the first direction is defined as a first edge, and the minimum spacing distance between the edge of the fastener and the first edge is a; the length of the first surface in the first direction is not greater than the length in the second direction, and the second direction intersects with the first direction; a module tab, welded to the first surface of the pole, and a welding track is arranged around the fastener; when a<4mm, the welding track includes a segmented weld track; when a≥4mm, the welding track includes a continuous weld track.

[0006] Optionally, in the same battery cell, there are two poles, and the two poles are spaced apart along the second direction; the welding trajectory of one of the two poles includes a segmented weld trajectory, and the welding trajectory of the other pole includes a continuous weld trajectory.

[0007] Optionally, the segmented weld trajectory includes: alternately arranged welding segments and avoidance fractures, and the avoidance fracture is located between the fastener and the first edge.

[0008] Optionally, a positioning structure is also provided on the pole; along the second direction, the positioning structure is spaced apart from the fastener, and the positioning structure is close to the first edge; the second direction is perpendicular to the first direction; the third direction is perpendicular to the first direction and the second direction respectively, and along the third direction, the orthographic projection of the welding trajectory on the first surface does not overlap with the orthographic projection of the positioning structure on the first surface.

[0009] Optionally, a portion of the welding track corresponding to the positioning structure is formed as an avoidance track, and the avoidance track is located between the positioning structure and the fastener.

[0010] Optionally, the avoidance track is formed into an angular structure shape.

[0011] Optionally, the corner structure shape includes a straight corner shape and / or a rounded corner shape.

[0012] Optionally, the welding tracks are distributed in a centrally symmetrical manner relative to the fastener.

[0013] Optionally, a portion of the segmented weld trajectory that is close to the fastener and extends along the first direction is connected to a bent trajectory segment, and the bent trajectory segment extends toward the fastener and / or away from the fastener.

[0014] Optionally, when the bending track segment extends away from the fastener, the bending track segment includes a first bending sub-segment and a second bending sub-segment connected in end to end, the first bending sub-segment extends along the second direction, and the second bending sub-segment extends along the first direction.

[0015] Optionally, in the same battery cell, there are two poles, and the two poles are spaced apart along the second direction; the welding trajectory of one of the two poles satisfies a<4mm, and the welding trajectory of the other pole satisfies a≥4mm.

[0016] Based on the same inventive concept, the second aspect of the present application also provides a battery pack, comprising the battery module as described in the first aspect.

[0017] From the above, it can be seen that for the battery module and battery pack provided by the present application, when the minimum spacing distance between the edge of the fastener and the first edge is ≥4mm, the welding trajectory can be designed as a continuous weld trajectory; and when the minimum spacing distance between the two is <4mm, the welding trajectory can be designed as a segmented weld trajectory to avoid the welding trajectory exceeding the first edge and to avoid the welding trajectory from contacting the fastener to prevent cold welding. In summary, corresponding to first surfaces of different sizes, matching welding trajectories can be set on the first surface to achieve reliable welding between the pole and the module tab, which effectively improves the structural design flexibility of the battery cell, so that the design of the battery cell and the pole is no longer restricted by the welding trajectory. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present application or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 A three-dimensional schematic diagram of a battery module according to an embodiment of the present application;

[0020] Figure 2 An exploded schematic diagram of a battery module according to an embodiment of the present application;

[0021] Figure 3 It is a three-dimensional schematic diagram of two adjacent battery cells in a battery module of an embodiment of the present application being connected via a module tab;

[0022] Figure 4 It is a top view schematic diagram of two adjacent battery cells in a battery module of an embodiment of the present application being connected via a module tab;

[0023] Figure 5 A schematic diagram of the positional relationship between a first welding track and a first surface of a battery module according to an embodiment of the present application;

[0024] Figure 6 It is a top view schematic diagram of another structure in which two adjacent battery cells in the battery module of an embodiment of the present application are connected via a module bar;

[0025] Figure 7 A schematic diagram of the positional relationship between the second welding track and the first surface of the battery module of an embodiment of the present application;

[0026] Figure 8 A schematic top view of a battery module of an embodiment of the present application showing that the same battery cell includes two poles with different structures;

[0027] Fig. 9 A schematic top view of a module tab of a battery module having a first welding track of an embodiment of the present application;

[0028] Fig.10 A schematic top view of a module tab of a battery module of an embodiment of the present application having a third type of welding track;

[0029] Fig.11 A schematic top view of a module tab of a battery module of an embodiment of the present application having a fourth welding track;

[0030] Fig.12 A schematic top view of a module tab of a battery module having a fifth welding track of an embodiment of the present application;

[0031] Fig.13 A schematic top view of a module tab of a battery module of an embodiment of the present application having a sixth welding track;

[0032] Fig.14 Schematic diagram of a top view of a module tab of a battery module with a seventh welding track of an embodiment of the present application;

[0033] Fig.15 A schematic top view of a module tab of a battery module having a second welding track of an embodiment of the present application;

[0034] Fig.16 A schematic top view of a module tab of a battery module having an eighth welding trajectory of an embodiment of the present application;

[0035] Fig.17 It is a top view schematic diagram of a module tab of a battery module having a ninth welding trajectory according to an embodiment of the present application.

[0036] Description of reference numerals:

[0037] 100, end plate assembly; 110, end plate body; 120, output pole base;

[0038] 200, middle plate; 300, side plate; 400, module cover;

[0039] 500, battery cell group; 510, battery cell; 511, pole; 5111, positioning structure; 5112, first surface; 5113, fastener; 5114, first edge;

[0040] 600, bus bar assembly; 610, module bar; 620, electrode output terminal;

[0041] 700, welding track; 710, avoidance fracture; 720, avoidance track; 730, bending track segment; 731, first bending sub-segment; 732, second bending sub-segment; 740, welding segment. DETAILED DESCRIPTION

[0042] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0043] It should be noted that the relative arrangement of the components, the numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise.

[0044] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0045] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0046] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be the usual meanings understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0047] like Figure 1 , Figure 1 A three-dimensional schematic diagram of a battery module is shown. Figure 1 The structure shown is used as an example for explanation. The battery module includes two end plate assemblies 100 and two side plates 300. The two side plates 300 and the two end plate assemblies 100 together form a circumferential frame of the battery module. A module upper cover 400 is also provided above the circumferential frame.

[0048] like Figure 2 , Figure 2The exploded schematic diagram of the battery module is shown. A middle plate 200 is arranged in the circumferential frame, and the middle plate 200 can be parallel to the side plate 300. Two battery cell groups 500 are also arranged in the circumferential frame, and the battery cell group 500 is located between the middle plate 200 and the side plate 300. Each battery cell group 500 includes a battery cell group 500 along the length direction of the battery module (such as Figure 2 A plurality of battery cells 510 are arranged in the circumferential direction (in the X1 direction in the figure). A busbar assembly 600 is arranged above the battery cell group 500, and the busbar assembly 600 includes a plurality of module bars 610, and each module bar 610 is respectively connected to the poles 511 of two adjacent battery cells 510 to achieve electrical connection between the two adjacent battery cells 510. The busbar assembly 600 also includes an electrode output terminal 620 (including a positive output terminal and a negative output terminal) extending outside the circumferential frame, and the portion of the electrode output terminal 620 located in the circumferential frame is connected to the pole 511 of the corresponding battery cell 510. The end plate assembly 100 includes an end plate body 110 and an output pole base 120 connected to the top of the end plate body 110, and the output pole base 120 is used to support the electrode output terminal 620. Typically, the output pole base 120 is made of an insulating material (such as plastic).

[0049] like Figure 3 , Figure 3 The figure shows a three-dimensional schematic diagram of two adjacent battery cells 510 connected by a module bar 610. Specifically, the two battery cells 510 are arranged side by side in the thickness direction, and a module bar 610 is disposed above two adjacent poles 511 on the same side. A welding track 700 is formed on the top surface of the module bar 610 to achieve the connection between the module bar 610 and the pole 511. Figure 4 , Figure 4 FIG. 5 is a top view schematic diagram showing two adjacent battery cells 510 connected via a module bar 610. Figure 4 Taking the structure shown in the figure as an example, the top surface of the pole 511 is defined as a first surface 5112, and the first surface 5112 is connected with a fastener 5113. For example, the fastener 5113 can be a battery core rivet. Figure 4 The edge of the first surface 5112 in the first direction (in the X2 direction) is defined as the first edge 5114, and the minimum spacing distance between the edge of the fastener 5113 and the first edge 5114 is a. The length of the first surface 5112 in the first direction is not greater than that in the second direction (such as Figure 4 The length in the Y2 direction) of the second direction intersects the first direction; the module bar 610 is welded to the first surface 5112 of the pole 511.

[0050] Figure 4 The situation shown is a situation where the distance between the first edge 5114 and the fastener 5113 is large. Figure 5 , Figure 5The schematic diagram of the positional relationship between the first welding track 700 and the first surface 5112 is shown. The welding track 700 is arranged around the fastener 5113. When a≥4mm, the welding track 700 includes a continuous weld track. When a≥4mm, the gap between the edge of the fastener 5113 and the first edge 5114 can meet the process requirements for setting the welding track 700, so the welding track 700 can be a continuous weld track.

[0051] like Figure 6 , Figure 6 A top view schematic diagram of another structure in which two adjacent battery cells 510 are connected via a module bar 610 is shown. Figure 6 The illustrated situation is a situation where the distance between the first edge 5114 and the fastener 5113 is small. Figure 7 , Figure 7 The schematic diagram shows the positional relationship between the second welding track 700 and the first surface 5112. When a<4 mm, the welding track 700 includes a segmented weld track.

[0052] When a is less than 4 mm, the gap between the edge of the fastener 5113 and the first edge 5114 is insufficient to set the welding track 700. In this case, the welding track 700 may not be provided with a weld at a position where the gap space is small, and may be provided with a weld at a position where the gap space meets the setting requirements, that is, the welding track 700 may be provided as a segmented weld track to ensure that the welding track 700 does not exceed the first edge 5114 and does not contact the fastener 5113.

[0053] In the battery module provided in the embodiment of the present application, when the minimum spacing distance a between the edge of the fastener 5113 and the first edge 5114 is ≥4mm, the welding track 700 can be designed as a continuous weld track; and when the minimum spacing distance a between the two is <4mm, the welding track 700 can be designed as a segmented weld track to prevent the welding track 700 from exceeding the first edge 5114, and the welding track 700 avoids contact with the fastener 5113 to prevent cold welding. In summary, corresponding to first surfaces 5112 of different sizes, matching welding tracks 700 can be set on the first surface 5112 to achieve reliable welding between the pole 511 and the module bar 610, which effectively improves the structural design flexibility of the battery cell, so that the design of the battery cell 510 and the pole 511 is no longer restricted by the welding track 700.

[0054] In some embodiments, the length of the first surface 5112 of the pole 511 in the second direction is greater than the length in the first direction, and the length of the welding track 700 in the second direction is greater than the length in the first direction.

[0055] According to the structural characteristic that the length of the first surface 5112 of the pole 511 in the second direction is longer than the length in the first direction, the welding track 700 is designed as a figure in which the length in the second direction is longer than the length in the first direction. This can effectively improve the space utilization rate of the first surface 5112. Compared with the track set as a circular track, the length of the welding track 700 of this embodiment is increased by 30% to 60%, and the overall area of ​​the welding track 700 is larger, which helps to improve the current flow capacity of the module bar 610.

[0056] like Figure 8 , Figure 8 A schematic diagram of a top view of the same battery cell 150 including two poles 511 of different structures is shown. In some embodiments, in the same battery cell 510, there are two poles 511, and the two poles 511 are spaced apart along the second direction; the welding track 700 of one of the two poles 511 includes a segmented weld track, and the welding track 700 of the other pole includes a continuous weld track.

[0057] by Figure 8 The structure and direction shown are taken as an example for further explanation. In the same battery cell 510, there are two poles 511, and the two poles are spaced apart along the second direction; the welding track 700 of one of the two poles 511 satisfies a<4mm, and the welding track 700 of the other satisfies a≥4mm. The structures of the two poles 511 on the same battery cell 510 are different, and the minimum spacing distance a1≥4mm between the edge of the fastener 5113 of the pole 511 on the left and the first edge 5114; the minimum spacing distance a2<4mm between the edge of the fastener 5113 of the pole 511 on the right and the first edge 5114.

[0058] In combination with the foregoing, the welding track 700 on the left pole 511 can be designed as a continuous weld track, and the welding track 700 on the right pole 511 can be designed as a segmented weld track, so that the two poles 511 with different structures can be reliably welded to the module bar 610.

[0059] like Figure 7 The segmented weld trajectory includes: alternately arranged welding segments 740 and avoidance breaks 710 , and the avoidance breaks 710 are located between the fastener 5113 and the first edge 5114 .

[0060] In combination with the above, the length of the first surface 5112 in the first direction is not greater than the length in the second direction, therefore, the gap space between the fastener 5113 and the first edge 5114 is the gap space of the minimum size between the fastener 5113 and the outer contour of the first surface 5112. Accordingly, the segmented weld track is provided with a avoidance break 710 at the position of the gap space to ensure that the welding track 700 neither contacts the fastener 5113 nor exceeds the edge of the first surface 5112; at the same time, a welding section 740 can be provided at other positions with larger gap spaces (such as the gap space between the fastener 5113 and the corner of the first surface 5112; or, when the minimum spacing distance between the edge of the fastener 5113 and the edge of the first surface 5112 in the second direction is ≥4mm, the gap space between the two) to ensure that the pole 511 can be reliably welded to the module bar 610.

[0061] like Fig. 9 , Fig. 9 A schematic diagram of a module bar 610 having a first welding track 700 is shown. In some embodiments, a positioning structure 5111 is further provided on the pole 511; Fig. 9 The second direction is in the Y2 direction (as in the Y2 direction), the positioning structure 5111 and the fastener 5113 are spaced apart, and the positioning structure 5111 is close to the first edge 5114; the second direction is in the Y2 direction (as in the Y2 direction), the positioning structure 5111 and the fastener 5113 are spaced apart, and the positioning structure 5111 is close to the first edge 5114; Fig. 9 The X2 direction in the figure is perpendicular to the third direction (such as Fig. 9 The direction perpendicular to the paper plane in the figure) is perpendicular to the first direction and the second direction respectively. Along the third direction, the orthographic projection of the welding trajectory 700 on the first surface 5112 does not coincide with the orthographic projection of the positioning structure 5111 on the first surface 5112.

[0062] Exemplarily, the positioning structure 5111 may be a battery cell anti-rotation column.

[0063] Exemplarily, two positioning structures 5111 are provided on each pole 511 , and the two positioning structures 5111 are distributed in a centrally symmetrical manner with respect to the fastener 5113 .

[0064] Generally, the positioning structure 5111 is located below the first surface 5112. If the welding track 700 passes directly above the positioning structure 5111, a cold weld will occur at the portion of the welding track 700 corresponding to the positioning structure 5111. To avoid the above situation, in this embodiment, the welding track 700 is designed to bypass the positioning structure 5111 to ensure that the pole 511 can be reliably welded to the module bar 610.

[0065] Specifically, Fig. 9The portion of the welding track 700 corresponding to the positioning structure 5111 is formed as an avoidance track 720 , and the avoidance track 720 is located between the positioning structure 5111 and the fastener 5113 .

[0066] by Fig. 9 In the first direction, the positioning structure 5111 on the left is close to the first edge 5114 at the bottom and away from the first edge 5114 at the top. Therefore, there is still a large space between the positioning structure 5111 on the left and the first edge 5114 at the top for setting the welding track 700. In order to utilize the space and enable the welding track 700 to avoid the positioning structure 5111, an avoidance track 720 is set at the portion of the welding track 700 close to the positioning structure 5111. The avoidance track 720 bypasses the positioning structure 5111 from the space between the positioning structure 5111 and the fastener 5113.

[0067] The welding track 700 of this embodiment ensures that its length along the second direction is long. By setting the avoidance track 720, it prevents the welding track 700 from contacting the positioning structure 5111, which can ensure that the module bar 610 has a high current carrying capacity and the welding quality between the pole 511 and the module bar 610.

[0068] like Fig.10 , Fig.10 A schematic diagram of a module bar 610 having a third welding track 700 is shown. In some embodiments, the welding track 700 may be elliptical, and the arc track between the positioning structure 5111 and the fastener 5113 may constitute an avoidance track 720 so that the elliptical welding track 700 avoids the positioning structure 5111.

[0069] like Fig.11 , Fig.11 A schematic diagram of a module bar 610 having a fourth welding track 700 is shown. In some embodiments, the welding track 700 may be diamond-shaped, and the inclined straight track between the positioning structure 5111 and the fastener 5113 may constitute an avoidance track 720 so that the diamond-shaped welding track 700 avoids the positioning structure 5111.

[0070] In addition to the above-mentioned welding track 700 having a regular shape, the welding track 700 may also have an irregular shape.

[0071] like Fig. 9 In some embodiments, the avoidance track 720 is formed into an angle structure shape, and the angle structure shape includes a straight angle shape and / or a rounded angle shape.

[0072] Fig. 9The welding track 700 in the figure is a position avoidance track 720 with a straight angle shape arranged on the basis of a rectangle, so that the welding track 700 can avoid the positioning structure 5111.

[0073] like Fig.12 , Fig.12 The schematic diagram of the module bar 610 with the fifth welding track 700 is shown. In addition to the avoidance track 720 with a straight angle shape, the avoidance track 720 with a rounded angle shape can also be used. Fig.12 The welding track 700 in the figure is a rounded avoidance track 720 arranged on the basis of a rectangle, so that the welding track 700 can avoid the positioning structure 5111.

[0074] It should be noted that the avoidance track 720 can be arranged only on the side where the positioning structure 5111 is located, or can be arranged symmetrically. Fig. 9 , the right positioning structure 5111 is located at the top, then the avoidance track 720 on the right side of the welding track 700 is only located at the top, and the bottom is still a rectangular structure. Fig.12 Although the positioning structure 5111 on the right side is only located at the top, the avoidance track 720 on the right side of the welding track 700 can also be symmetrically arranged at the top and the bottom.

[0075] In addition to preventing the welding track 700 from contacting the positioning structure 5111 by using the avoidance track 720, the length of the welding track 700 in the second direction can also be shortened to avoid the positioning structure 5111. Fig.13 , Fig.13 FIG. 6 is a schematic diagram of a module bar 610 having a sixth welding track 700. Along the first direction, the orthographic projection of the welding track 700 on the first edge 5114 does not overlap with the orthographic projection of the positioning structure 5111 on the first edge 5114. Fig.13 Taking the structure and direction shown as an example, along the second direction, the welding track 700 is located as a whole between the two positioning structures 5111. In this space, the welding track 700 can be in any shape while ensuring that it does not contact the fastener 5113. The shape design of the welding track 700 can be relatively flexible.

[0076] like Fig.14 , Fig.14 A schematic diagram of a module bar 610 with a seventh welding track 700 is shown. In some embodiments, a portion of the segmented weld track proximate to the fastener 5113 and extending along the first direction is connected with a bent track segment 730, which extends toward the fastener 5113 and / or away from the fastener 5113.

[0077] Of course, when a≥4 mm, the welding track 700 may also include a discontinuous weld track. Fig.14Taking the structure and direction shown as an example, the segmented weld track may include two welding segments 740 spaced apart along the second direction. Taking the right welding segment 740 as an example, it includes a vertical portion extending along the first direction, and the upper end of the vertical portion may be connected to a bending track segment 730 extending toward the fastener 5113 (hereinafter referred to as the upper bending track segment). At the same time, the lower end of the vertical portion may be connected to a bending track segment 730 extending away from the fastener 5113 (hereinafter referred to as the lower bending track segment), and the lower bending track segment may be located between the lower first edge 5114 and the positioning structure 5111.

[0078] The bent track segment 730 is provided to help improve the space utilization of the first surface 5112, so that the welding track 700 can extend as long as possible within the range of the first surface 5112, so as to achieve the purpose of enhancing the flow capacity of the module bar 610 by increasing the length of the welding track 700. The overall track shape of the welding track 700 is relatively simple, easy to form, and has a high degree of process feasibility.

[0079] like Fig.14 In some embodiments, when the bending track segment 730 extends away from the fastener 5113, the bending track segment 730 includes a first bending sub-segment 731 and a second bending sub-segment 732 connected in end to end, the first bending sub-segment 731 extends along the second direction, and the second bending sub-segment 732 extends along the first direction.

[0080] Exemplarily, the first bending sub-segment 731 may be in a straight line or in an arc shape.

[0081] Illustratively, the second bending sub-segment 732 may be in a straight line or in an arc shape.

[0082] Exemplarily, each bending track segment 730 may include one, two or more first bending sub-segments 731 ; correspondingly, each bending track segment 730 may also include one, two or more second bending sub-segments 732 .

[0083] The bending track segment 730 includes a first bending sub-segment 731 extending along the second direction, and a second bending sub-segment 732 extending along the first direction, so that the bending track segment 730 can be serpentine as a whole to more fully utilize the space between the first edge 5114 and the positioning structure 5111, which helps to increase the total length of the welding track 700 and enhance the current flow capacity of the module bar 610.

[0084] like Fig.14 In some embodiments, the second bending sub-segment 732 is spaced apart from the positioning structure 5111. In order to ensure that the welding track 700 does not contact the positioning structure 5111, the second bending sub-segment 732 needs to be spaced apart from the positioning structure 5111. Fig.14Taking the structure shown as an example, the second bending sub-segment 732 and the positioning structure 5111 can be longitudinally aligned. When the second bending sub-segment 732 is extended, its tail end can be close to the positioning structure 5111, but it is necessary to maintain a certain distance from the positioning structure 5111 to avoid the occurrence of cold welding between the pole 511 and the module bar 610 due to the contact between the second bending sub-segment 732 and the positioning structure 5111.

[0085] Generally, the positioning structure 5111 is distributed on the pole 511 in a centrally symmetrical form relative to the fastener 5113. Therefore, in some embodiments, the welding track 700 is distributed in a centrally symmetrical form relative to the fastener 5113. In this way, the design difficulty of the welding track 700 can be reduced, and it can also be ensured that the entire welding track 700 will not contact the positioning structure 5111, thereby avoiding the occurrence of cold welding.

[0086] In combination with the above content, it can be known that when the minimum spacing distance a between the edge of the fastener 5113 and the first edge 5114 is less than 4 mm, the welding track 700 needs to be provided with a avoidance break 710 in the portion between the edge of the fastener 5113 and the first edge 5114 to avoid contact between the welding track 700 and the fastener 5113. However, the provision of the avoidance break 710 will result in a reduction in the total length of the welding track 700. The provision of the bent track section 730 can solve this problem. When a ≥ 4 mm, the welding track 700 can select a continuous weld track or a discontinuous weld track according to actual conditions.

[0087] like Fig.15 , Fig.15 A schematic diagram of a module bar 610 having a second welding track 700 is shown. Fig.15 To further illustrate the direction in the figure, when the portion of the welding track 700 extending along the first direction is far away from the fastener 5113, a bent track segment 730 extending toward the fastener 5113 can be provided to extend the overall length of the welding track 700. The two bent track segments 730 located above are spaced apart to form a position-avoiding break 710. When the portion of the welding track 700 extending along the first direction is arc-shaped, it can transition to the bent track segment 730 through an arc-shaped transition. Fig.16 , Fig.16 The schematic diagram of the module bar 610 with the eighth welding track 700 is shown. When the portion of the welding track 700 extending along the first direction is a straight line, it can transition to the bent track segment 730 through a straight line angle.

[0088] like Fig.17 , Fig.17 FIG. 6 is a schematic diagram of a module bar 610 having a ninth welding track 700. Fig.17Taking the direction in the figure as an example, when the portion of the welding track 700 extending along the first direction is close to the fastener 5113, a bent track segment 730 extending away from the fastener 5113 can be provided to extend the overall length of the welding track 700. The structure and beneficial effects of the bent track segment 730 are similar to those of Fig.14 The structure and beneficial effects of the lower bending track segment are the same and will not be repeated here.

[0089] Based on the same inventive concept and in combination with the description of the battery modules of the above embodiments, this embodiment provides a battery pack having the corresponding technical effects of the battery modules of the above embodiments, which will not be described in detail herein.

[0090] A battery pack includes the battery module as described in the above embodiments.

[0091] It should be noted that the above describes some embodiments of the present application. Other embodiments are within the scope of the appended claims.

[0092] The various embodiments in the present application 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.

[0093] The description of the present application is given for the purpose of illustration and description, and is not intended to be exhaustive or to limit the present application to the disclosed form. Many modifications and variations are obvious to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present application, and to enable those of ordinary skill in the art to understand the present application and thus design various embodiments with various modifications suitable for specific purposes.

[0094] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present application (including the claims) is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0095] Although the present application has been described in conjunction with specific embodiments thereof, many alternatives, modifications and variations of these embodiments will be apparent to those skilled in the art in light of the foregoing description.

[0096] The embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of the present application.

Claims

1. A battery module, characterized in that: include: A battery cell, comprising a pole, a first surface of the pole being connected to a fastener; The edge of the first surface in the first direction is defined as a first edge, and the minimum spacing distance between the edge of the fastener and the first edge is a; the length of the first surface in the first direction is not greater than the length in the second direction, and the second direction intersects the first direction; A module bar, welded to the first surface, with a welding track arranged around the fastener; When a<4mm, the welding trajectory includes a segmented welding trajectory; When a≥4 mm, the welding trajectory includes a continuous weld trajectory.

2. The battery module according to claim 1, characterized in that: In the same battery cell, there are two poles, and the two poles are spaced apart along the second direction; The welding trajectory of one of the two poles comprises a segmented weld trajectory, and the welding trajectory of the other pole comprises a continuous weld trajectory.

3. The battery module according to claim 1, characterized in that: The segmented weld trajectory includes: welding segments and avoidance fractures that are alternately arranged, and the avoidance fracture is located between the fastener and the first edge.

4. The battery module according to claim 1, characterized in that: The pole is also provided with a positioning structure; along the second direction, the positioning structure and the fastener are spaced apart, and the positioning structure is close to the first edge; the second direction is perpendicular to the first direction; The third direction is perpendicular to the first direction and the second direction respectively. Along the third direction, the orthographic projection of the welding track on the first surface does not overlap with the orthographic projection of the positioning structure on the first surface.

5. The battery module according to claim 4, characterized in that: The portion of the welding track corresponding to the positioning structure is formed as an avoidance track, and the avoidance track is located between the positioning structure and the fastener.

6. The battery module according to claim 5, characterized in that: The avoidance track is formed in an angular structure shape.

7. The battery module according to claim 6, characterized in that: The corner structure shape includes a straight corner shape and / or a rounded corner shape.

8. The battery module according to claim 1, characterized in that: The welding tracks are distributed in a centrally symmetrical manner relative to the fastener.

9. The battery module according to claim 1, characterized in that: A portion of the segmented weld trajectory that is close to the fastener and extends along the first direction is connected to a bent trajectory segment, and the bent trajectory segment extends toward the fastener and / or away from the fastener.

10. The battery module according to claim 9, characterized in that: When the bending track segment extends away from the fastener, the bending track segment includes a first bending sub-segment and a second bending sub-segment connected in end to end, the first bending sub-segment extends along the second direction, and the second bending sub-segment extends along the first direction.

11. The battery module according to claim 1, characterized in that: In the same battery cell, there are two poles, and the two poles are spaced apart along the second direction; The welding trajectory of one of the two poles satisfies a<4mm, and the welding trajectory of the other pole satisfies a≥4mm.

12. A battery pack, characterized in that: Comprising a battery module as claimed in any one of claims 1 to 11.

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