Cover plate assembly and battery

Abstract

The utility model relates to the technical field of batteries, in particular to a cover plate assembly and a battery. The utility model provides a cover plate assembly and a battery. The cover plate assembly comprises a cover plate body and a pole, wherein a liquid injection hole and an anti-explosion valve are arranged on the cover plate body; the pole columns comprise a positive pole column and a negative pole column, and the positive pole column and the negative pole column are arranged on the cover plate body; and the liquid injection hole and the anti-explosion valve are separated by the positive pole or the negative pole. According to the cover plate assembly and the battery provided by the utility model, the problem that the explosion-proof valve is easy to crack during liquid injection can be solved.

Description

Technical Field

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

[0002] The battery cell includes a shell, a battery cell and a cover assembly, wherein the battery cell is arranged inside the shell, and the cover assembly is sealed at the opening of the shell. The cover assembly of the battery cell includes a cover, a pole, a liquid injection hole, an explosion-proof valve and a connecting piece, wherein the pole includes a positive pole and a negative pole, and the pole is connected to the pole ear of the battery cell through a connecting piece. The liquid injection hole is used to inject electrolyte into the battery shell, and the explosion-proof valve plays a role in preventing the battery cell from exploding due to excessive pressure in the battery shell.

[0003] In the prior art, the injection hole and the explosion-proof valve are adjacent and are arranged between the positive pole and the negative pole. In order to facilitate injection, the interior of the battery housing needs to be evacuated before injection to make the interior of the battery housing in a negative pressure state, and then the electrolyte is injected into the battery housing.

[0004] When the electrolyte is injected into the battery case, the internal pressure of the battery case is converted from negative pressure to positive pressure. However, at the moment when the negative pressure is converted to positive pressure, the explosion-proof valve often ruptures.

[0005] Therefore, how to solve the problem that the explosion-proof valve is prone to rupture during liquid injection in the prior art has become an important technical problem to be solved by those skilled in the art. Utility Model Content

[0006] In view of this, the utility model provides a cover plate assembly and a battery, which can solve the problem that the explosion-proof valve is easily broken during liquid injection.

[0007] In a first aspect, an embodiment of the present utility model provides a cover plate assembly, comprising a cover plate body and a pole; wherein:

[0008] The cover plate body is provided with a liquid injection hole and an explosion-proof valve;

[0009] The poles include a positive pole and a negative pole, and the positive pole and the negative pole are arranged on the cover body;

[0010] The liquid injection hole and the explosion-proof valve are separated by the positive pole or the negative pole.

[0011] Beneficial effects:

[0012] In the technical solution provided by the utility model, the explosion-proof valve and the injection hole are separated by the positive pole or the negative pole. Unlike the prior art in which the explosion-proof valve and the injection hole are adjacently arranged, the distance between the explosion-proof valve and the injection hole in the solution of the utility model is relatively far. When injecting liquid into the battery housing through the injection hole, even if there is a positive and negative pressure switch in the internal pressure of the battery housing, the impact on the explosion-proof valve at the moment of the positive and negative pressure switch is small, thereby avoiding the problem of explosion-proof valve rupture. Moreover, the injection hole is far away from the explosion-proof valve, which can avoid the problem of electrolyte splashing to the explosion-proof valve position during the injection process, causing corrosion of the explosion-proof valve.

[0013] In an optional embodiment, the explosion-proof valve is arranged in the middle of the cover body, the positive pole and the negative pole are respectively arranged on two opposite sides of the explosion-proof valve, and the injection hole is arranged near the edge of the cover body.

[0014] Beneficial effects:

[0015] The positive pole and the negative pole are arranged close to the center of the cover body, and both are close to the pole ears of the battery cell, thereby shortening the current path from the pole ears to the poles, reducing heat generation, and improving the current capacity of the entire battery cell.

[0016] In an optional embodiment, a connecting piece is further included, and the connecting piece includes a pole connecting portion and a pole lug connecting portion, the pole connecting portion is connected to the pole, and the pole lug connecting portion is used to connect to the pole lug of the battery cell.

[0017] Beneficial effects:

[0018] Since the positive and negative poles are close to the tabs of the battery cell, the pole connecting part and the tab connecting part of the connecting piece can be arranged in close distance, thereby reducing the area of ​​the connecting piece, using less material for the connecting piece, reducing the cost, and reducing the overall weight of the battery.

[0019] In an optional embodiment, the connecting piece is configured as a regular polygonal structure or a circular structure, the pole connecting portion is configured in a central area of ​​the connecting piece, and the pole lug connecting portions are configured on both sides of the pole connecting portion.

[0020] Beneficial effects:

[0021] The connecting piece is set to a regular polygonal structure or a circular structure, specifically a square, a regular pentagon, a regular hexagon, a circle, etc. The pole connection part can be set in the central area of ​​the connecting piece, and the pole ear connection part is set near the edge of the connecting piece. In this way, the overall structure of the connecting piece is regular and easy to process.

[0022] In an optional embodiment, the connecting piece is provided with a notch structure, and the notch structure separates the pole connecting portion from the pole lug connecting portion.

[0023] Beneficial effects:

[0024] The connecting plate is provided with a notch structure, which separates the pole connecting part from the lug connecting part. When the lug connecting part is welded to the lug of the battery cell, even if the lug connecting part is deformed, the deformation of the lug connecting part will not be transmitted to the pole connecting part due to the action of the notch structure, thereby avoiding the problem of unstable connection between the pole and the pole connecting part of the connecting plate.

[0025] In addition, the location where the indentation structure is set on the connecting piece has a smaller thickness, and when the current exceeds the preset value, the location will fuse. Therefore, the location where the indentation structure is set on the connecting piece can be used as a fuse to play an overload protection role.

[0026] In an optional embodiment, the indentation structure includes a first indentation structure, the first indentation structure is arranged in an arc shape and is arranged around the pole connecting portion; and / or

[0027] The indentation structure includes a second indentation structure, the second indentation structure is arranged in a straight line, and the second indentation structure is located between the pole lug connection portion and the pole connection portion.

[0028] In an optional embodiment, a material reduction hole structure or a material reduction groove structure is provided in a region of the connecting sheet other than the pole connecting portion and the pole tab connecting portion.

[0029] Beneficial effects:

[0030] By providing a material-reducing hole structure or a material-reducing groove structure, the material used for the connecting sheet can be reduced, the weight of the connecting sheet can be reduced, and the cost and weight of the battery can be reduced. Moreover, the material-reducing hole structure or the material-reducing groove structure is provided in an area outside the pole connection part and the pole lug connection part, and will not affect the normal connection with the pole and the pole lug.

[0031] In an optional embodiment, the negative electrode column includes a first conductor layer and a second conductor layer, the first conductor layer is provided with a groove on the top, the second conductor layer is compounded in the groove, and the top surfaces of the first conductor layer and the second conductor layer are flush; wherein the second conductor layer is suitable for welding with the bar sheet.

[0032] Beneficial effects:

[0033] The negative electrode column includes a first conductor layer and a second conductor layer, the first conductor layer and the second conductor layer are compositely formed, and the second conductor layer is composited in the groove of the first conductor layer, and the second conductor layer is used for welding with the bar sheet, specifically, the material of the second conductor layer is the same as that of the bar sheet, so that the two can be welded together. Different from the composite pole in the prior art (the second conductor layer in the prior art is composited on the entire top surface of the first conductor layer), the second conductor layer provided in the present solution is not completely composited on the top surface of the first conductor layer, but composited in the groove of the first conductor layer, and the first conductor layer and the second conductor layer are flush with each other. With such a configuration, the top thickness of the negative electrode column is smaller without affecting the welding with the bar sheet, so that the saved space can be left to the inside of the battery, thereby increasing the capacity of the battery.

[0034] In an optional embodiment, the material of the first conductor layer is copper, and the material of the second conductor layer is aluminum.

[0035] In a second aspect, the utility model provides a battery, comprising a cover plate assembly as described in any one of the above items.

[0036] With such arrangement, the battery provided by the utility model can solve the problem that the explosion-proof valve is easily broken during liquid injection. The derivation process of this beneficial effect is generally similar to the derivation process of the beneficial effect brought by the above-mentioned cover plate assembly, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 This is a schematic diagram of a cover assembly from a first viewing angle according to an embodiment of the utility model;

[0039] Figure 2 A schematic diagram of a cover plate assembly from a second viewing angle according to an embodiment of the utility model;

[0040] Figure 3 This is a schematic diagram of the connecting piece structure in one embodiment of the utility model;

[0041] Figure 4 This is a schematic diagram of the connecting piece structure in another embodiment of the utility model;

[0042] Figure 5 This is a schematic diagram of the connecting piece structure in another embodiment of the utility model;

[0043] Figure 6 Schematic diagram of the negative pole structure of an embodiment of the utility model.

[0044] Description of reference numerals:

[0045] 11. Cover plate body; 12. Explosion-proof valve; 13. Positive pole; 14. Negative pole; 141. First conductor layer; 142. Second conductor layer; 15. Liquid injection hole; 16. Connecting piece; 161. Pole pole connecting part; 162. Ear connecting part; 163. First indentation structure; 164. Second indentation structure; 165. Material reduction groove structure. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0047] Please refer to Figure 1-Figure 6 The cover plate assembly provided in this embodiment includes a cover plate body 11 and a pole. The cover plate body is configured as a plate-like structure for covering the shell opening of the battery cell. A liquid injection hole 15 and an explosion-proof valve 12 are provided on the cover plate body.

[0048] The injection hole 15 is used to inject electrolyte into the battery housing. The injection hole 15 may be provided with a one-way valve structure. To facilitate the injection of electrolyte, the battery housing is evacuated by the one-way valve structure before injection to put the battery housing in a negative pressure state. Then, the electrolyte is injected into the battery housing by the injection device. Under the positive pressure of the injection device and the negative pressure inside the battery housing, the electrolyte can quickly enter the battery housing.

[0049] The explosion-proof valve 12 serves to prevent the risk of the battery shell exploding due to the high pressure inside the battery cell shell. Specifically, the explosion-proof valve 12 is located relatively weaker than other positions of the battery shell. When the pressure inside the battery shell exceeds the threshold of the explosion-proof valve 12, the explosion-proof valve 12 first explodes to release the pressure, thereby avoiding the problem of the battery shell as a whole exploding due to the accumulation of a large pressure inside the battery shell.

[0050] The cover body 11 is provided with a positive electrode column 13 and a negative electrode column 14 , which are connected to the electrodes of other battery cells through a bar sheet, thereby realizing series connection or parallel connection of multiple battery cells.

[0051] In this embodiment, Figure 1 and Figure 2 As shown, the injection hole 15 and the explosion-proof valve 12 provided on the cover body 11 are separated by the positive pole 13 or the negative pole 14. In some embodiments, the explosion-proof valve 12 can be provided in the middle of the cover body 11, the positive pole 13 and the negative pole 14 are provided at both sides of the explosion-proof valve 12, respectively, and the injection hole 15 is provided on the side of the positive pole 13 or the negative pole 14 relatively far away from the explosion-proof valve 12, that is, the explosion-proof valve 12 and the injection hole 15 are separated by the positive pole 13 or the negative pole 14.

[0052] In this embodiment, the explosion-proof valve 12 and the injection hole 15 are separated by the positive pole 13 or the negative pole 14. Unlike the prior art in which the explosion-proof valve 12 and the injection hole 15 are adjacently arranged, the distance between the explosion-proof valve 12 and the injection hole 15 in this embodiment is relatively far. When the battery housing is injected through the injection hole 15, even if the pressure inside the battery housing switches between positive and negative pressures, the impact on the explosion-proof valve 12 at the moment of the positive and negative pressure switching is small, thereby avoiding the problem of the explosion-proof valve 12 rupture. Moreover, the injection hole 15 is far away from the explosion-proof valve 12, which can avoid the problem of electrolyte splashing to the explosion-proof valve 12 during the injection process, causing the explosion-proof valve 12 to corrode.

[0053] In a further embodiment, the explosion-proof valve 12 is arranged in the middle position in the length direction of the cover body 11, the positive electrode column 13 and the negative electrode column 14 are respectively arranged on both sides of the explosion-proof valve 12 in the length direction of the cover body 11, and the injection hole 15 is arranged at a position close to one end of the length direction of the cover body 11.

[0054] In this arrangement, the positive electrode column 13 and the negative electrode column 14 are arranged close to the center of the cover body 11, and both are close to the pole ears of the battery cell, thereby shortening the current path from the pole ears to the poles, which can reduce heat generation and improve the current capacity of the entire battery cell.

[0055] In a further embodiment, the cover plate assembly further includes a connecting piece 16, which includes a pole connecting portion 161 and a pole tab connecting portion 162, wherein the pole connecting portion 161 is connected to the pole, and the pole tab connecting portion 162 is used to connect to the pole tab of the battery cell.

[0056] The connecting piece 16 is divided into a positive connecting piece and a negative connecting piece. The positive connecting piece is used to connect the positive electrode column 13 and the positive electrode ear, and the negative connecting piece is used to connect the negative electrode column 14 and the negative electrode ear. For example, the pole connecting portion 161 of the positive connecting piece can be welded to the lower end surface of the positive electrode column 13 (one end located inside the battery housing) by welding, and the pole ear connecting portion 162 of the positive connecting piece is connected to the positive pole ear of the battery cell by welding. The pole connecting portion 161 of the negative connecting piece can be welded to the lower end surface of the negative electrode column 14 (one end located inside the battery housing) by welding, and the pole ear connecting portion 162 of the negative connecting piece is connected to the negative pole ear of the battery cell by welding.

[0057] The positive electrode column 13 and the negative electrode column 14 are arranged close to the center of the cover body 11, and the positive electrode connecting piece and the negative electrode connecting piece are also close to the center of the cover body 11. Since the positive electrode ear and the negative electrode ear of the battery cell are closer to the center of the cover body 11, Figure 3-Figure 5 As shown, the pole connection portion 161 and the pole ear connection portion 162 of the connecting piece 16 (positive connecting piece and negative connecting piece) can be arranged in close proximity, thereby reducing the area of ​​the connecting piece 16. The connecting piece 16 uses less material, reduces the cost, and reduces the overall weight of the battery.

[0058] In a further embodiment, the connecting piece 16 is configured as a regular polygonal structure or a circular structure, for example, the connecting piece 16 can be configured as a square, a regular pentagon, a regular hexagon, a circle, etc. The central area of ​​the connecting piece 16 is a pole connecting portion 161, which is used to connect to the pole, and the connection can be achieved by welding. The pole ear connecting portion 162 is arranged on two opposite sides of the pole connecting portion 161.

[0059] With such arrangement, the overall shape of the connecting piece 16 is regular and easy to process. Moreover, the distance between the pole connecting portion 161 and the pole ear connecting portion 162 is short, and the current path is short, which can reduce heat generation and improve the current carrying capacity of the entire battery cell.

[0060] In a further embodiment, the connecting sheet 16 is provided with a dent structure, which separates the pole connecting portion 161 from the pole lug connecting portion 162. Specifically, one of the positive connecting sheet and the negative connecting sheet may be provided with the dent structure, or both may be provided with the dent structure.

[0061] The connecting piece 16 is provided with a notch structure, which separates the pole connection part 161 from the pole lug connection part 162. When the pole lug connection part 162 is welded to the pole lug of the battery cell, even if the pole lug connection part 162 is deformed, due to the action of the notch structure, the deformation of the pole lug connection part 162 will not be transmitted to the pole connection part 161, thereby avoiding the problem of unstable connection between the pole and the pole connection part 161 of the connecting piece 16.

[0062] In addition, the position where the indentation structure is set on the connecting piece 16 has a smaller thickness, and when the current exceeds the preset value, the position will fuse. Therefore, the position where the indentation structure is set on the connecting piece 16 can be used as a fuse to play an overload protection role.

[0063] In some embodiments, the indentation structure includes a first indentation structure 163 and / or a second indentation structure 164; wherein the first indentation structure 163 is configured to be arc-shaped and is configured to surround the pole connecting portion 161, such as Figure 4The second indentation structure 164 is set to be linear, and the second indentation structure 164 is between the pole ear connection part 162 and the pole connection part 161, as shown in FIG. Figure 3 shown.

[0064] In some embodiments, the first indentation structure 163 and / or the second indentation structure 164 may be etched on the connection sheet 16 by an etching process, or may be punched on the connection sheet 16 by a stamping process.

[0065] The first indentation structure 163 is arranged in an arc shape, and the pole connection part 161 is arranged in the space surrounded by the first indentation structure 163. In this way, the first indentation structure 163 forms a weak part of the connecting sheet 16, and the pole connection part 161 is separated from the pole lug connection part 162 by the first indentation structure 163. When the pole lug connection part 162 is welded with the pole lug of the battery cell, even if the pole lug connection part 162 is deformed, under the blocking effect of the first indentation structure 163, the deformation of the pole lug connection part 162 will not be transmitted to the pole connection part 161, and thus the pole connection part 161 will not be deformed. The connection reliability between the pole connection part 161 and the pole is ensured.

[0066] In some embodiments, the pole connection portion 161 and the pole lug connection portion 162 may also be separated by a linear second indentation structure 164. Specifically, the transition portion between each pole lug connection portion 162 and the pole connection portion 161 is provided with the above-mentioned second indentation structure 164. The second indentation structure 164 also constitutes a weak portion on the connecting plate 16. When the pole lug connection portion 162 and the pole lug are deformed during welding, the second indentation structure 164 can also prevent the deformation from being transmitted to the pole connection portion 161, causing deformation of the pole connection portion 161.

[0067] It should be noted that, in this embodiment, either the first indentation structure 163 or the second indentation structure 164 may be disposed on the connecting sheet 16 , or both may be disposed on the connecting sheet 16 at the same time.

[0068] In a further embodiment, the connecting piece 16 is provided with a material reduction hole structure or a material reduction groove structure 165 in the area other than the pole connecting portion 161 and the pole ear connecting portion 162, such as Figure 5 By providing the material-reducing hole structure or the material-reducing groove structure 165, the material used for the connecting piece 16 can be reduced, the weight of the connecting piece 16 can be reduced, and the cost and weight of the battery can be reduced. Moreover, the material-reducing hole structure or the material-reducing groove structure 165 is provided in the area outside the pole connecting portion 161 and the pole lug connecting portion 162, and will not affect the normal connection with the pole and the pole lug.

[0069] In a further embodiment, Figure 6 As shown, the negative electrode column 14 includes a first conductor layer 141 and a second conductor layer 142, a groove is provided on the top of the first conductor layer 141, the second conductor layer 142 is compounded in the groove, and the top surfaces of the first conductor layer 141 and the second conductor layer 142 are flush with each other; wherein the second conductor layer 142 is suitable for welding with the bar sheet.

[0070] The negative electrode column 14 includes a first conductor layer 141 and a second conductor layer 142. The first conductor layer 141 and the second conductor layer 142 are compositely formed, and the second conductor layer 142 is composited in the groove of the first conductor layer 141. The second conductor layer 142 is used for welding with the bar piece. Specifically, the material of the second conductor layer 142 is the same as that of the bar piece so that the two can be welded together.

[0071] Different from the composite pole in the prior art (the second conductor layer 142 in the prior art is composited on the entire top surface of the first conductor layer 141), the second conductor layer 142 provided in this embodiment is not completely composited on the top surface of the first conductor layer 141, but composited in the groove of the first conductor layer 141, and the first conductor layer 141 and the second conductor layer 142 are flush. In this way, the top thickness of the negative pole 14 is small without affecting the welding with the bar sheet, and the saved space can be left to the inside of the battery, thereby increasing the capacity of the battery.

[0072] In an optional embodiment, the material of the first conductor layer 141 is copper, and the material of the second conductor layer 142 is aluminum. Copper is suitable as the negative electrode material of the battery, and aluminum is compounded on the copper. By welding the aluminum with the aluminum tab, the connection reliability with the tab can be ensured.

[0073] The positive electrode column 13 can be made of all-aluminum material, which is suitable as a positive electrode material for batteries and suitable for welding with aluminum tabs.

[0074] An embodiment of the utility model further provides a battery, comprising a cover plate assembly as described in any one of the above items.

[0075] With such arrangement, the battery provided by the utility model can solve the problem that the explosion-proof valve 12 is easily broken during liquid injection. The derivation process of this beneficial effect is generally similar to the derivation process of the beneficial effect brought by the above-mentioned cover plate assembly, and will not be repeated here.

[0076] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A cover plate assembly, characterized in that: It comprises a cover plate body (11) and a pole; wherein, The cover plate body (11) is provided with a liquid injection hole (15) and an explosion-proof valve (12); The poles include a positive pole (13) and a negative pole (14), and the positive pole (13) and the negative pole (14) are arranged on the cover plate body (11); The liquid injection hole (15) and the explosion-proof valve (12) are separated by the positive electrode column (13) or the negative electrode column (14).

2. A cover plate assembly according to claim 1, characterized in that: The explosion-proof valve (12) is arranged in the middle of the cover body (11), the positive pole (13) and the negative pole (14) are respectively arranged on two opposite sides of the explosion-proof valve (12), and the injection hole (15) is arranged at a position close to the edge of the cover body (11).

3. A cover plate assembly according to claim 1 or 2, characterized in that: It also comprises a connecting piece (16), the connecting piece (16) comprising a pole connecting portion (161) and a pole lug connecting portion (162), the pole connecting portion (161) being connected to the pole, and the pole lug connecting portion (162) being used to be connected to a pole lug of a battery cell.

4. A cover plate assembly according to claim 3, characterized in that: The connecting piece (16) is arranged in a regular polygonal structure or a circular structure, the pole connecting portion (161) is arranged in the central area of ​​the connecting piece (16), and the pole lug connecting portion (162) is arranged on both sides of the pole connecting portion (161).

5. A cover plate assembly according to claim 4, characterized in that: The connecting sheet (16) is provided with a notch structure, and the notch structure separates the pole connecting portion (161) from the pole lug connecting portion (162).

6. A cover plate assembly according to claim 5, characterized in that: The indentation structure comprises a first indentation structure (163), the first indentation structure (163) is arranged in an arc shape and is arranged around the pole connecting portion (161); and / or The indentation structure comprises a second indentation structure (164), the second indentation structure (164) is arranged in a straight line, and the second indentation structure (164) is located between the pole lug connection portion (162) and the pole connection portion (161).

7. A cover plate assembly according to claim 4, characterized in that: A material reduction hole structure or a material reduction groove structure (165) is provided in the area outside the pole connecting portion (161) and the pole lug connecting portion (162) of the connecting sheet (16).

8. The cover plate assembly according to claim 1, characterized in that: The negative electrode column (14) comprises a first conductor layer (141) and a second conductor layer (142), wherein a groove is arranged on the top of the first conductor layer (141), the second conductor layer (142) is compounded in the groove, and the top surfaces of the first conductor layer (141) and the second conductor layer (142) are flush with each other; wherein the second conductor layer (142) is suitable for welding with a bar.

9. A cover plate assembly according to claim 8, characterized in that: The material of the first conductor layer (141) is copper, and the material of the second conductor layer (142) is aluminum.

10. A battery, characterized in that: It comprises the cover plate assembly as described in any one of claims 1 to 9.

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