Battery cell structure, battery module, and battery pack

Abstract

The application discloses a kind of electric core structure, battery module and battery pack, electric core structure includes shell, electrode assembly, top cover assembly and pin component, electrode assembly is set in shell, electrode assembly includes electric core body and by the tab of electric core body extension, top cover assembly includes top cover body and electrode terminal set on top cover body, top cover body connects shell, pin component includes mutually connected terminal connecting portion and tab guide portion, terminal connecting portion is connected with electrode terminal, tab guide portion is connected with tab, terminal connecting portion is connected with tab guide portion, the side of tab guide portion away from electrode assembly is outer surface, part surface of the outer surface is concave and forms groove, part tab is contained in the groove, part tab is contained in groove, tab is hidden in the thickness space of tab guide portion, to reduce the space occupied by tab, tab end does not need to cut, and metal scrap is not generated.

Description

Technical Field

[0001] This invention relates to the field of battery cell structure, and particularly to a battery cell structure, battery module, and battery pack. Background Technology

[0002] The battery contains tabs and leads, with the leads electrically connected to the tabs. The existing process for welding tabs and leads involves first ultrasonically welding the tabs, then cutting the tabs, and finally laser welding the tabs and leads.

[0003] There are many problems with the soldering method between the pins and the tabs. First, the cutting process of the tabs will generate a lot of metal shavings, which are difficult to clean and will remain inside the cell, which can easily lead to insulation failure. Second, the tabs of the two cells are wrapped around the pins from both sides. Due to the existing pin structure, the tabs overlap on the pins. If the tabs are not cut, the thickness of this overlapping area will increase, occupying internal space of the battery and reducing the energy density of the battery. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the prior art, which are large space occupation and low battery energy density due to the unreasonable connection method between the pin and the tab and the stacking of the tab on the pin.

[0005] To solve the above-mentioned technical problems, the present invention provides a cell structure, a battery module, and a battery pack.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is: a battery cell structure, comprising a housing, an electrode assembly, a top cover assembly, and a lead component. The electrode assembly is disposed within the housing and includes a battery cell body and a tab extending from the battery cell body. The top cover assembly includes a top cover body and electrode terminals disposed on the top cover body. The top cover body is connected to the housing. The lead component includes a terminal connection portion and a tab guide portion connected to each other. The terminal connection portion is connected to the electrode terminal, and the tab guide portion is connected to the tab. The side of the tab guide portion away from the electrode assembly is an outer surface, and a portion of the outer surface is recessed to form a groove, in which the tab portion is accommodated.

[0007] In this design, the tab extends from the cell body and is attached to the outer surface of the tab guide. Part of the tab is accommodated in the groove, so that part of the tab is hidden within the thickness space of the tab guide, thereby reducing the space occupied by the tab end and thus improving the energy density of the cell. In addition, the tab end does not need to be cut, so no metal debris is generated, and the insulation inside the cell is guaranteed.

[0008] Preferably, at least some of the tabs overlap, and the overlapping portion is accommodated in the groove.

[0009] In this design, the excess length of the tabs overlaps and is accommodated in the groove, reducing the space occupied by the overlapping part of the tabs in the thickness direction of the tab guide, which is beneficial to improving the energy density of the cell.

[0010] Preferably, at least two of the tabs are bent from two sides of the tab guide to the outer surface, and the ends of at least two of the tabs overlap, with the overlapping portion being accommodated in the groove.

[0011] In this design, at least two tabs are bent from the side closest to the electrode assembly to the outer surface, and the overlapping portions of the ends of at least two tabs are accommodated in a groove, which reduces the space occupied by the overlapping portions of the tab ends and helps to improve the energy density of the battery cell.

[0012] Preferably, the groove extends along the length direction of the electrode guide portion, and the length of the groove is greater than or equal to the length of the electrode.

[0013] In this design, since the length of the tab is less than or equal to the length of the groove, the tab can be completely placed inside the groove without any excess portion protruding outside the groove, thus reducing the space occupied by the tab.

[0014] Preferably, the groove is located at the middle position of the outer surface.

[0015] In this design, the groove is located in the middle of the outer surface, making the distance between the two sides of the electrode guide and the groove consistent. This allows two electrodes of the same length to wrap around the electrode guide from both sides, and the overlapping area of ​​the two electrodes is exactly aligned with the groove, thus defining the position of the two electrode assemblies. In addition, since the electrodes of the two electrode assemblies are of the same length, there is no need to consider the order of the two electrode assemblies, avoiding the situation where the overlapping area of ​​the electrodes cannot be aligned with the groove due to misoperation, thus providing a good error-proof effect.

[0016] Preferably, the sidewall of the groove smoothly transitions with the outer surface to form a first arc portion.

[0017] In this design, the tab extends from the outer surface to the groove and bends at the first arc portion, thus preventing the tab from breaking due to pressure from sharp corners.

[0018] Preferably, the bottom of the groove has a bottom wall surface, and the height difference between the bottom wall surface and the outer surface is at least the thickness of a single tab.

[0019] In this design, two tabs respectively embrace the tab guide from both sides. The end of the first tab is recessed into a groove, and the end of the tab forms a high horizontal surface and a low horizontal surface from high to low. The second tab rests on the low horizontal surface. Due to the height difference between the bottom wall surface and the outer surface, the height difference between the high horizontal surface and the low horizontal surface is at least the thickness of a single tab. Therefore, the upper surface of the second tab will not protrude from the upper surface of the first tab.

[0020] Preferably, the bottom of the groove has a bottom wall surface, which is recessed in the direction close to the electrode assembly to form a through groove; the electrode assembly passes through the through groove and enters the groove, and the end of the electrode is bent and overlaps the bottom wall surface.

[0021] In this design, the tab passes through the through groove from the middle of the tab guide, and the end of the tab extends into the groove and rests on the bottom wall. In this way, the end of the tab does not protrude from the outer surface, which is beneficial to improving the energy density of the cell.

[0022] A battery module comprising the aforementioned cell structure.

[0023] In this solution, the battery module utilizes the aforementioned cell structure, which saves internal space and thus improves the overall energy density of the battery module.

[0024] A battery pack comprising the aforementioned cell structure or the aforementioned battery module.

[0025] In this solution, the use of the aforementioned cell structure or battery module inside the battery pack can reduce the amount of unused space occupied inside the battery pack, thereby increasing the amount of electricity contained in the battery pack per unit volume.

[0026] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of the present invention.

[0027] The positive and progressive effects of this invention are as follows: the tab extends from the cell body and is attached to the outer surface of the tab guide. Part of the tab is accommodated in the groove, so that part of the tab is hidden in the thickness space of the tab guide, thereby reducing the space occupied by the tab end, which is conducive to improving the energy density of the cell. In addition, the tab end does not need to be cut, so no metal debris is generated, and the insulation inside the cell is guaranteed. Attached Figure Description

[0028] Figure 1 This is an exploded structural diagram of the first embodiment of the battery cell structure of the present invention.

[0029] Figure 2 for Figure 1 A schematic diagram of the top cover assembly and pin components.

[0030] Figure 3 for Figure 2 A magnified schematic diagram of the middle pin component.

[0031] Figure 4 This is a schematic diagram of the electrode guide portion surrounding the electrode tab in Embodiment 1 of the battery cell structure of the present invention.

[0032] Figure 5 This is a schematic diagram of the pin component in Embodiment 2 of the battery cell structure of the present invention.

[0033] Figure 6 for Figure 5 Schematic diagram of the structure on the inner and outer surfaces.

[0034] Figure 7 This is a schematic diagram of the electrode guide portion surrounding the electrode tab in Embodiment 2 of the battery cell structure of the present invention.

[0035] Explanation of reference numerals in the attached figures:

[0036] Battery cell body 10

[0037] JE11

[0038] Top cover assembly 12

[0039] Pin component 13

[0040] Top cover body 14

[0041] Electrode terminal 15

[0042] Terminal connection part 16

[0043] Electrode guide part 17

[0044] outer surface 18

[0045] Groove 19

[0046] First arc section 20

[0047] Bottom wall 21

[0048] Through slot 22

[0049] Second arc section 23

[0050] First electrode 24

[0051] Second pole 25

[0052] Casing 26 Detailed Implementation

[0053] The present invention will be described more clearly and completely below by way of embodiments and in conjunction with the accompanying drawings, but the present invention is not limited to the scope of the embodiments.

[0054] Example 1

[0055] Figures 1-4 The illustration shows an embodiment of a battery cell structure according to the present invention, such as... Figure 1 and Figure 2 As shown, it includes a housing 26, an electrode assembly, a top cover assembly 12, and a pin component 13. The electrode assembly is disposed inside the housing 26 and includes a cell body 10 and a tab 11 extending from the cell body 10.

[0056] The battery cell body 10 can be a stacked body or a wound core.

[0057] The top cover assembly 12 includes a top cover body 14 and electrode terminals 15 disposed on the top cover body 14, and the top cover body 14 is connected to the housing 26.

[0058] The pin component 13 includes a terminal connection portion 16 and a tab guide portion 17 that are connected to each other. The terminal connection portion 16 is connected to the electrode terminal 15, and the tab guide portion 17 is connected to the tab 11. The terminal connection portion 16 is connected to the tab guide portion 17.

[0059] The side of the tab guide 17 away from the electrode assembly is the outer surface 18. A portion of the outer surface 18 is recessed to form a groove 19, in which the tab 11 is partially accommodated.

[0060] In this embodiment, the tab 11 is partially accommodated in the groove 19, so that part of the tab 11 is hidden within the thickness space of the tab guide portion 17, thereby reducing the space occupied by the tab 11 and thus improving the energy density of the battery cell. In addition, since the excess part of the tab 11 can be accommodated in the groove 19, there is no need to cut off the excess part at the end of the tab 11, and no metal debris is generated. The insulation of the battery cell will not be damaged due to the presence of metal debris, which helps to improve the safety of the battery cell.

[0061] Preferably, at least a portion of the tabs 11 overlap, and the overlapping portion is accommodated in the groove 19.

[0062] It should be noted that in some embodiments, the end of the tab 11 is folded and accommodated in the groove 19; in other embodiments, the middle part of the tab 11 is folded and accommodated in the groove 19. Both of these embodiments can hide the tab 11 within the thickness space of the tab guide 17, thereby reducing the space occupied by the tab 11.

[0063] Preferably, at least two of the tabs 11 are bent from the two sides of the tab guide 17 to the outer surface 18, and the ends of at least two of the tabs 11 overlap, with the overlapping portion being accommodated in the groove 19.

[0064] In this example, the two tabs 11 are bent from the two sides of the tab guide 17 to the outer surface 18, and the overlapping part of the ends of the two tabs 11 is accommodated in the groove 19, which reduces the space occupied by the overlapping part of the tab ends and helps to improve the energy density of the cell.

[0065] In other embodiments of this application, a plurality of tabs 11 are bent from one side of the tab guide 17 to the outer surface 18, and a plurality of tabs 11 are bent from the other side of the tab guide 17 to the outer surface 18. The plurality of tabs 11 on both sides overlap at the outer surface 18, and the overlapping portion is accommodated in the groove 19.

[0066] Preferably, the groove 19 extends along the length direction of the tab guide 17, and the length of the groove 19 is greater than or equal to the length of the tab 11.

[0067] In some embodiments, the length of the groove 19 is greater than the length of the tab 11. Since the length of the tab 11 is less than the length of the groove 19, the tab 11 can be completely placed inside the groove 19 without any excess portion protruding outside the groove, thereby reducing the space occupied by the tab 11.

[0068] In other embodiments, the length of the groove 19 is equal to the length of the tab 11, and the tab 11 can be positioned exactly within the groove 19.

[0069] like Figure 4 As shown, in some embodiments, there are two electrode assemblies stacked together. Two tabs 11 respectively hug the tab guide 17 from both sides. The two tabs 11 overlap at the outer surface 18, and the overlapping part is disposed in the groove 19, which reduces the space occupied by the overlapping part of the tabs 11 and improves the space utilization.

[0070] It should be noted that the number of electrode assemblies is not limited to the two mentioned above. In other embodiments of this application, the number of electrode assemblies is one, with one electrode tab 11 on it hugging the electrode guide 17 from one side of the electrode guide 17. The excess part at the end of the electrode tab 11 is folded and placed in the groove 19 to avoid cutting off the excess electrode tab 11 and to reduce the space occupied by the end of the electrode tab 11.

[0071] like Figure 3 As shown, in some embodiments, the groove 19 is located in the middle of the outer surface 18.

[0072] In this example, the two tabs 11 are of the same length and are bent from both sides onto the outer surface 18 of the tab guide 17. The two tabs 11 overlap at the middle position of the outer surface 18, and the overlapping part is directly opposite the position of the groove 19.

[0073] The groove 19 is located in the middle of the outer surface 18, so that the distance between the two sides of the electrode guide 17 and the groove 19 is the same, so that the two electrodes 11 of the same length can wrap around the electrode guide 17 from both sides of the electrode guide 17 respectively. The overlapping area of ​​the two electrodes 11 is exactly opposite to the position of the groove 19, so as to define the position of the two electrode assemblies.

[0074] In addition, since the tabs 11 of the two electrode assemblies are of the same length, there is no need to consider the installation order of the two electrode assemblies, which avoids the situation where the overlapping area of ​​the tabs 11 cannot be aligned with the groove 19 due to misoperation, and has a good foolproof effect.

[0075] It should be noted that the position of the groove 19 is not limited to the middle position mentioned above. In other embodiments of this application, the groove 19 may be offset from the center position of the electrode guide 17 as needed to accommodate the different lengths of the two electrodes 11.

[0076] like Figure 3 As shown, preferably, the sidewall of the groove 19 smoothly transitions to the outer surface 18 to form a first arc portion 20.

[0077] In this example, the tab 11 extends from the outer surface 18 to the groove 19 and bends at the first arc portion 20. Since the first arc portion 20 has a smooth surface, the tab 11 is prevented from being squeezed by sharp corners and breaking.

[0078] Preferably, the bottom of the groove 19 has a bottom wall surface 21, and the height difference between the bottom wall surface 21 and the outer surface 18 is at least the thickness of a single tab 11.

[0079] like Figure 4 As shown, in some instances, the first tab 24 bends from one side of the tab guide 17 and hugs the tab guide 17, and the end of the first tab 24 bends and is recessed into the groove 19, forming a high horizontal surface and a low horizontal surface from high to low.

[0080] The second tab 25 bends from the other side of the tab guide 17 and hugs the tab guide 17, and extends on the outer surface 18 to rest on the low horizontal surface.

[0081] The first tab 24 is attached to the outer surface 18 and the bottom wall surface 21 of the groove 19. The height difference between the bottom wall surface 21 and the outer surface 18 is the thickness of one tab 11. The height difference between the high horizontal surface and the low horizontal surface is also the thickness of one tab 11. Therefore, the upper surface of the second tab 25 is flush with the upper surface of the first tab 24, thereby reducing the thickness of the protruding tab 11.

[0082] In other embodiments of this application, the height difference between the bottom wall surface 21 and the outer surface 18 is greater than the thickness of one tab 11. In this case, the second tab 25 is recessed at the groove 19 so that its upper surface does not protrude from the upper surface of the first tab 24, thus achieving the same effect.

[0083] Preferably, the terminal connection portion 16 and the electrode guide portion 17 form an L-shaped bent plate. The L-shaped bent plate fits against the side of the electrode assembly, and because it is a plate, it occupies little space.

[0084] Example 2

[0085] Figures 5-7 The illustration shows a second embodiment of the battery cell structure of this application, which includes a housing 26, an electrode assembly, a top cover assembly 12, and a lead component 13. The housing 26, electrode assembly, and top cover assembly 12 are consistent with those of Embodiment 1, while the lead component 13 has features different from those of Embodiment 1, as detailed below:

[0086] like Figure 5 and Figure 6 As shown, in this embodiment, the bottom of the groove 19 on the electrode guide 17 has a bottom wall surface 21. The bottom wall surface 21 is recessed in the direction close to the electrode assembly to form a through groove 22. The through groove 22 cuts off the central area of ​​the bottom wall surface 21 so that the remaining bottom wall surface 21 surrounds the edge of the through groove 22.

[0087] like Figure 7 As shown, the electrode 11 passes through the through groove 22 and enters the groove 19 through the electrode assembly, and the end of the electrode 11 is bent and overlapped on the bottom wall surface 21.

[0088] The tab 11 adopts the above connection method. The end of the tab 11 does not protrude from the outer surface 18. The end of the tab is hidden in the groove 19, which occupies the thickness space of the tab guide 17, but does not occupy the space outside the tab guide 17. This reduces the space occupied by the tab inside the cell and is conducive to improving the energy density of the cell.

[0089] like Figure 5 As shown, preferably, the side wall of the through groove 22 and the bottom wall 21 of the groove 19 smoothly transition to form the second arc portion 23.

[0090] In this example, the tab 11 extends from the through groove 22, bends and overlaps the bottom wall surface 21, and the tab 11 bends at the second arc portion 23. Since the second arc portion 23 has a smooth transition surface, the tab 11 is prevented from being squeezed by sharp corners and breaking.

[0091] like Figure 6 As shown, the through groove 22 is a U-shaped groove, and the opening of the U-shaped groove is away from the terminal connection part 16.

[0092] In this example, the pin component 13 is mounted on the fixture using a U-shaped groove. The fixture fixes the pin component 13 so that the tab 11 can be soldered to the tab guide 17.

[0093] Example 3

[0094] A battery module comprising the cell structure described in the above embodiments.

[0095] In this example, the battery module uses the cell structure described above, which can save internal space and thus improve the overall energy density of the battery module.

[0096] Example 4

[0097] A battery pack comprising the above-described cell structure and / or the above-described battery module.

[0098] In this example, the application of the aforementioned cell structure or battery module inside the battery pack can reduce the amount of unused space occupied inside the battery pack, thereby increasing the amount of electricity contained in the battery pack per unit volume.

[0099] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A battery cell structure, characterized in that, It includes: case; An electrode assembly is disposed within the housing, the electrode assembly comprising a battery cell body and tabs extending from the battery cell body; A top cover assembly, the top cover assembly including a top cover body and electrode terminals disposed on the top cover body, the top cover body being connected to the housing; The pin component includes a terminal connection portion and a tab guide portion that are connected to each other. The terminal connection portion is connected to the electrode terminal, and the tab guide portion is connected to the tab. The side of the tab guide portion away from the electrode assembly is an outer surface, and a portion of the outer surface is recessed to form a groove, in which the tab portion is accommodated. The bottom of the groove has a bottom wall surface, and at least two of the electrodes are bent from the two sides of the electrode guide to the outer surface. At least a portion of the electrodes overlap, and the overlapping portion is accommodated in the groove and fits against the bottom wall surface.

2. The cell structure as described in claim 1, characterized in that, At least two of the said electrodes overlap at their ends.

3. The cell structure as described in claim 1, characterized in that, The groove extends along the length of the electrode guide portion, and the length of the groove is greater than or equal to the length of the electrode.

4. The cell structure as described in claim 1, characterized in that, The groove is located at the middle position of the outer surface.

5. The cell structure as described in claim 1, characterized in that, The sidewall of the groove smoothly transitions with the outer surface to form a first arc portion.

6. The cell structure as described in claim 1, characterized in that, The height difference between the bottom wall surface and the outer surface is at least equal to the thickness of a single tab.

7. A battery module, characterized in that, It includes the cell structure as described in any one of claims 1-6.

8. A battery pack, characterized in that, It includes the cell structure as described in any one of claims 1-6 or the battery module as described in claim 7.

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