Cover plate assembly, battery monomer and battery module

Abstract

The utility model relates to the technical field of batteries, particularly provides a cover plate assembly for a single battery, the single battery and a battery module, and aims to solve the technical problem that a cover plate liquid injection hole sealing assembly of the single battery is poor in sealing performance due to mechanical contact sealing. Therefore, the cover plate assembly for the battery monomer comprises a cover plate, a plurality of liquid injection holes and a plurality of liquid injection holes, the first end of the liquid injection channel is connected with the cover plate along the edge of the liquid injection hole; the sealing element is arranged in the liquid injection channel; wherein a groove is formed in the inner wall of the liquid injection channel, and the sealing piece abuts against an opening of the groove. The groove is formed in the inner wall of the liquid injection channel, the sealing piece abuts against the opening of the groove, on the premise that the material surface machining standard of the liquid injection channel is consistent, the sealing piece can make line contact with the opening end of the groove, and compared with an existing mode that the sealing piece makes surface contact with the liquid injection channel, the sealing effect is better.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field, specifically provide a cover plate subassembly, battery monomer and battery module. BACKGROUND

[0002] On the cover plate subassembly constituting the battery shell, be provided with the electrolyte injection hole for injecting electrolyte to the inside of battery shell. When injecting electrolyte in lithium ion battery, open the battery top cover and then inject electrolyte, after completing the liquid injection, use the sealing nail to seal the liquid injection hole, then through laser welding the sealing nail is welded to the cover plate, thereby realizing the sealing of the cover plate. Or directly cover the aluminum sheet on the liquid injection hole, carry out the sealing welding to the liquid injection hole on the aluminum sheet and the cover plate. But the above-mentioned liquid injection hole sealing structure form is complex, the process is complex, and the cost is high. Through the design of the welding connection of the sealing nail and the liquid injection hole, because the electrolyte is easy to remain around the liquid injection hole, it is easy to cause the problems of poor welding such as virtual welding, porosity and crack of the sealing nail, and the sealing nail is easy to deform, therefore the reliability of the liquid injection hole sealing structure form is relatively low. And the sealing plastic nail may be caused by aging and poor cooperation with the liquid injection hole, which has the risk of falling into the secondary battery.

[0003] In order to solve the above problems, usually the hard sealing mode is used to seal the liquid injection hole, and the sealing nail is not welded. However, the sealing element of hard sealing belongs to mechanical contact sealing with the liquid injection hole, and the surface quality of the contact surface is required to be high. Therefore, the problem needs to be solved urgently. SUMMARY

[0004] The utility model aims at solving the above technical problem, that is, solving the technical problem of poor sealing performance of the cover plate liquid injection hole sealing assembly of the battery monomer caused by mechanical contact sealing.

[0005] In the first aspect, the utility model provides a kind of cover plate subassembly for battery monomer, comprising: cover plate, is equipped with liquid injection hole;Liquid injection channel, the first end of liquid injection channel is connected with cover plate along the edge of liquid injection hole;Sealing element, is equipped in liquid injection channel;Wherein, the inner wall of liquid injection channel is provided with recess, and sealing element and the opening of recess abut.

[0006] In the above technical solution, recess is arranged on the inner wall of liquid injection channel, and sealing element abuts with the opening of recess. Under the premise that the material surface of liquid injection channel is processed with consistent standard, sealing element can be in contact with the opening end line of recess, and compared with the mode that existing sealing element is in contact with liquid injection channel, the sealing effect is better.

[0007] In some embodiments, the sealing element covers the opening of the recess.

[0008] In the above technical solution, the opening of the recess is covered by the sealing element, which can ensure that the sealing element has two line seals with the opening end of the recess, and enhances the sealing performance.

[0009] In some embodiments, a plurality of grooves are provided, and the plurality of grooves are arranged along the center line direction of the liquid injection channel.

[0010] In the above technical solution, the number of grooves is set to be multiple, which can increase the number of line contacts between the liquid injection channel and the sealing element, and further enhance the sealing performance.

[0011] In some embodiments, the width of the groove is greater than or equal to 0.01 mm and less than or equal to 0.8 mm; and / or, the depth of the groove is greater than or equal to 0.01 mm and less than or equal to 0.8 mm.

[0012] In the above technical solution, if the width or depth of the groove is set too large, it will affect the overall strength of the liquid injection channel; if the width or depth of the groove is set too small, it will affect the sealing effect of the sealing element and the liquid injection channel.

[0013] In some embodiments, the sealing element is spherical, and the diameter of the sealing element is greater than or equal to 2 mm and less than or equal to 6.5 mm.

[0014] In the above technical solution, the sealing element is set to be spherical, which can enhance the sealing effect with the liquid injection hole; if the diameter of the sealing element is set too large or too small, it will affect the sealing effect of the sealing element and the liquid injection hole.

[0015] In some embodiments, the material of the sealing element is metal material or polymer material.

[0016] In the above technical solution, the material of the sealing element is selected as metal material or polymer material, which is beneficial to the cooperation of the sealing element and the liquid injection channel and enhances the sealing effect.

[0017] In some embodiments, the diameter of the liquid injection hole is greater than or equal to 2 mm and less than or equal to 6 mm; and / or, the wall thickness of the liquid injection channel is greater than or equal to 0.1 mm and less than or equal to 0.8 mm.

[0018] In the above technical solution, if the diameter of the liquid injection hole is set too small, it will affect the liquid injection efficiency of the electrolyte, and at the same time, when welding the positive electrode, the welding needle needs to be inserted into the electrode assembly through the liquid injection hole, so if the diameter of the liquid injection hole is set too small, it will be difficult to insert the welding needle; if the diameter of the liquid injection hole is set too large, the cell hole of the corresponding electrode assembly will also increase, which will affect the overall energy density of the electrode assembly.

[0019] In some embodiments, the first end of the liquid injection channel has a first round corner.

[0020] In the above technical solution, a first round corner is provided at the connection between the liquid injection channel and the cover plate, which can play a guiding role when the sealing element is installed to seal the liquid injection hole, and facilitate the assembly of the sealing element.

[0021] In some embodiments, the second end of the liquid injection channel has a second rounded corner.

[0022] In the above technical solution, the second end of the liquid injection channel has a second rounded corner, compared with the liquid injection channel whose second end is a right angle, during the process of assembling the cover plate to the battery monomer, the liquid injection channel can avoid interfering with the roll core hole in the electrode assembly, and then scratching the diaphragm of the electrode assembly, causing the positive and negative short circuit or leakage, causing the battery to overheat, fire, explosion and other safety accidents; at the same time, the diaphragm damage will also cause the mixing and reaction of the internal materials of the battery, resulting in the situation of reduced capacity, reduced carrying capacity or reduced performance.

[0023] In some embodiments, the cover plate and the liquid injection channel are integrally formed.

[0024] In the above technical solution, the cover plate and the liquid injection channel are integrally formed, which simplifies the production process and reduces the manufacturing cost.

[0025] In a second aspect, the utility model also provides a battery monomer, including shell, the shell has opening, still include above-mentioned cover plate assembly, cover plate assembly sets up in opening.

[0026] The battery monomer has the same advantages as the above-mentioned cover plate assembly relative to the prior art, which will not be repeated here.

[0027] In a third aspect, the utility model also provides a battery module, the battery module includes a plurality of above-mentioned battery monomers.

[0028] The battery module has the same advantages as the above-mentioned cylindrical battery monomer relative to the prior art, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments, it should be understood that the following drawings only show some embodiments of the present application, therefore should not be regarded as the limitation to the scope, for the ordinary skilled person in the art, on the premise of not paying the creative labor, can also obtain other related drawings according to these drawings;

[0030] Fig. 1 It is the structure schematic diagram of battery monomer provided by the utility model embodiment;

[0031] Fig. 2 It is the partial sectional view of battery monomer provided by the utility model embodiment;

[0032] Fig. 3 It is the partial sectional view of cover plate assembly provided by the utility model embodiment;

[0033] LIST OF REFERENCE NUMERALS

[0034] 1, battery monomer; 2, cover plate assembly; 3, cover plate; 4, liquid injection hole; 5, liquid injection channel; 6, sealing element; 7, groove; 8, first fillet; 9, second fillet; 10, shell; 11, top wall; 12, side wall; 13, pole. DETAILED DESCRIPTION

[0035] The preferred embodiments of the present application will be described below with reference to the accompanying drawings. Those skilled in the art will understand that these embodiments are only used to explain the technical principles of the present application, and are not intended to limit the protection scope of the present application.

[0036] It should be noted that in the description of the present application, the terms "inner", "outer", "top", "bottom", and the like, which indicate the direction or positional relationship, are based on the direction or positional relationship shown in the drawings, which is only for the convenience of description, and does not indicate or imply that the device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", "fourth" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance.

[0037] In addition, it should be noted that in the description of the present application, unless otherwise explicitly specified and limited, the terms "mounting", "setting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrally connected. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0038] In the embodiments of the present application, the same reference signs represent the same components, and for the sake of brevity, detailed description of the same components is omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device, are only exemplary and should not constitute any limitation on the present application.

[0039] Please refer to Figs. 1-3 , Figs. 1-3 The structure schematic diagram of the cover plate assembly for the battery monomer and the battery monomer provided by the embodiments of the present application.

[0040] As Figs. 1-3As shown, the cover plate assembly 2 comprises a cover plate 3, in the embodiment, the cover plate 3 is adapted to the shape of the battery cell 1, for example, the battery cell 1 is a cylindrical battery cell, and the cover plate 3 is circular. The cover plate 3 is provided with a liquid injection hole 4, which is arranged at the center of the cover plate 3. The cover plate assembly 2 comprises a liquid injection channel 5, the first end of the liquid injection channel 5 is connected with the cover plate 3 along the edge of the liquid injection hole 4. In some embodiments, the liquid injection channel 5 can be welded with the cover plate 3 or formed integrally with the cover plate 3. In the case of the liquid injection channel 5 being formed integrally with the cover plate 3, the liquid injection channel 5 can be punched from the cover plate 3. In the embodiment, the cover plate assembly 2 further comprises a sealing element 6, which is arranged in the liquid injection channel 5 and arranged in the liquid injection hole 4 after the liquid injection in the battery cell 1 is completed, to prevent liquid leakage or air leakage. The inventor found that when the sealing element 6 cooperates with the liquid injection channel 5, the sealing element 6 and the liquid injection channel 5 are in a face-to-face contact sealing mode. When the surface processing standard of the material of the liquid injection channel 5 is low, there will be several gaps in the inner surface of the liquid injection channel 5 in the center line direction. The existence of these gaps leads to the leakage of electrolyte, which affects the sealing effect of the sealing element 6. At the same time, improving the surface processing standard of the material of the liquid injection channel 5 is difficult to produce and manufacture, and the cost is high. Based on this, the inner wall of the liquid injection channel 5 is provided with a groove 7, and the opening of the groove 7 abuts against the sealing element 6. Due to the arrangement of the groove 7, the opening end of the sealing element 6 and the groove 7 is in a face-to-line contact sealing mode, which prevents the leakage of electrolyte caused by the gap in the inner surface of the liquid injection channel 5, and the sealing effect is better. Further, the sealing element 6 covers the opening of the groove 7, which can ensure that the sealing element 6 and the opening end of the groove 7 have two line seals, and the sealing performance is enhanced. In some embodiments, the number of grooves 7 can be multiple, and the multiple grooves 7 are arranged along the center line direction of the liquid injection channel 5. The spacing between the multiple grooves 7 can be the same or different, which can achieve the purpose of enhancing the sealing effect. Further, the width of the groove 7 is greater than or equal to 0.01 millimeter and less than or equal to 0.8 millimeter. Optionally, the width of the groove 7 can be 0.01 millimeter, 0.02 millimeter, 0.03 millimeter, or 0.8 millimeter. The size of the width of the groove 7 can achieve the sealing effect and ensure the strength of the liquid injection channel 5, which is not limited herein. Preferably, the width of the groove 7 is 0.4 millimeter. The depth of the groove 7 is greater than or equal to 0.01 millimeter and less than or equal to 0.8 millimeter. The size of the depth of the groove 7 can achieve the sealing effect and ensure the strength of the liquid injection channel 5, which is not limited herein. Optionally, the depth of the groove 7 can be 0.01 millimeter, 0.02 millimeter, 0.03 millimeter, or 0.8 millimeter. Preferably, the depth of the groove 7 is 0.4 millimeter. If the width or depth of the groove 7 is set too large, it will affect the overall strength of the liquid injection channel 5; if the width or depth of the groove 7 is set too small, it will affect the sealing effect of the sealing element 6 and the liquid injection channel 5.

[0041] In the embodiment, the sealing member 6 is in a spherical shape, and the spherical sealing member 6 and the hard sealing of the liquid injection channel 5 can enhance the sealing effect. The diameter of the sealing member 6 is greater than or equal to 2 mm and less than or equal to 6.5 mm. The diameter of the sealing member 6 can be selected to ensure the sealing effect of the sealing member 6 and the liquid injection channel 5, and is not limited herein. Alternatively, the diameter of the sealing member 6 can be 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, or 6.5 mm. Preferably, the diameter of the sealing member 6 is 4 mm. Further, the material of the sealing member 6 is a metal material or a polymer material, and alternatively, the material of the sealing member 6 can be carbon steel, other metal materials, or composite polymer materials. In some embodiments, the first end of the liquid injection channel 5 (the end of the liquid injection channel 5 close to the liquid injection hole 4) has a first round corner 8. In the embodiment, the connection between the liquid injection channel 5 and the cover plate 3 has the first round corner 8, and when the sealing member 6 is installed to seal the liquid injection hole 4, the first round corner 8 can serve as a guide to facilitate the assembly of the sealing member 6. Further, the second end of the liquid injection channel 5 (the end of the liquid injection channel 5 away from the liquid injection hole 4) has a second round corner 9, that is, the second round corner 9 is machined on the second end of the liquid injection channel 5 using a cutting tool. Compared with the liquid injection channel 5 with a straight angle at the second end, the interference between the flange and the roll core hole in the electrode assembly can be avoided during the assembly of the cover plate 3 to the battery monomer 1, thereby scratching the diaphragm of the electrode assembly, causing the positive and negative electrodes to short circuit or leak, and causing safety accidents such as battery overheating, fire, explosion, and the like.

[0042] As shown in Figs. 1-3 The cylindrical battery monomer of the embodiment includes a shell 10 having an opening at one end. In the embodiment, the shell 10 is a hollow structure with one side open, serving as a containing cavity for containing an electrode assembly and electrolyte, and the electrode assembly is arranged in the containing cavity of the shell 10. The shape of the shell 10 can be determined according to the specific shape of the electrode assembly, and in the embodiment, the electrode assembly is in a cylindrical structure, and the shell 10 is selected as a cylindrical shell 10. The shell 10 can be positively charged, negatively charged, or not charged. The cover plate assembly 2 is arranged at the opening of the shell 10, and the cover plate assembly 2 is electrically connected with the shell 10 and the electrode assembly, respectively. In the embodiment, the shell 10 is directly connected with the electrode assembly, and the shell 10 is charged. Alternatively, the cover plate assembly 2 and the shell 10 can be connected by welding, so that the cover plate assembly 2 and the shell 10 can have substantially the same potential.

[0043] In the embodiment, as shown in Figs. 1-3As shown, in the embodiment, the shell 10 comprises a side wall 12 and a top wall 11, the top wall 11 is arranged opposite to the opening and connected to the side wall 12. The side wall 12 and the top wall 11 can be an integrally formed structure, that is, the shell 10 is an integrally formed member. In addition, the side wall 12 and the top wall 11 can also be two members arranged separately, and then connected together by welding or the like, which is not limited here. The side wall 12 is a cylindrical structure, and the top wall 11 is a plate-shaped structure, the shape of which corresponds to the shape of the side wall 12. One end of the side wall 12 forms an opening, and the top wall 11 is connected to the other end of the side wall 12 away from the opening. In some embodiments, the top wall 11 has an electrode lead-out hole, and the pole 13 is arranged on the top wall 11 in an insulating manner, and the pole 13 can be fixed integrally on the outside of the top wall 11, or can extend into the inside of the shell 10 through the electrode lead-out hole. The embodiment utilizes the opening process to form the electrode lead-out hole for mounting the pole 13 on the top wall 11, and the top wall 11 is processed and formed from the shell 10, and the arrangement of the electrode lead-out hole will not affect the flatness of the top wall 11, and the connection strength of the top wall 11 and the busbar is enhanced. The top wall 11 and the pole 13 can serve as two output poles of the cylindrical battery monomer, simplify the structure of the cylindrical battery monomer, and ensure the overcurrent capacity of the cylindrical battery monomer. The top wall 11 and the pole 13 are arranged at the same end of the cylindrical battery terminal, so that the busbar can be assembled to the same side, simplifying the assembly process and improving the efficiency of assembling multiple cylindrical battery monomers into a group. In some embodiments, the electrode assembly has a positive tab and a negative tab, the positive tab is connected to the pole 13, and the negative tab is connected to the cover plate assembly 2; alternatively, the positive tab is connected to the cover plate assembly 2, and the negative tab is connected to the pole 13. When the positive tab is connected to the pole 13 and the negative tab is connected to the cover plate assembly 2, the pole 13 is the positive output pole of the cylindrical battery monomer, and the cover plate assembly 2 is the negative output pole of the cylindrical battery monomer; when the positive tab is connected to the cover plate assembly 2 and the negative tab is connected to the pole 13, the pole 13 is the negative output pole of the cylindrical battery monomer, and the cover plate assembly 2 is the positive output pole of the cylindrical battery monomer. The positive tab and the negative tab are arranged at two ends of the electrode assembly, which can reduce the risk of positive and negative tab conduction, and also increase the overcurrent area of the positive tab and the overcurrent area of the negative tab.

[0044] The utility model also provides a battery module with multiple battery monomers, the battery module has the same advantages as the battery monomer in the embodiment compared with the prior art, and details are not repeated here.

[0045] The technical scheme of the utility model has been described in combination with the preferred embodiments shown in the drawings, but those skilled in the art can easily understand that the protection scope of the utility model is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to related technical features without deviating from the principles of the utility model, and the technical schemes after the changes or replacements will all fall within the protection scope of the utility model.

Claims

1. A cover plate assembly for a battery cell, characterized by, The application relates to a cover plate assembly for a battery cell. The cover plate assembly comprises: a cover plate provided with a liquid injection hole; a liquid injection channel, a first end of the liquid injection channel being connected to the cover plate along an edge of the liquid injection hole; a sealing member arranged in the liquid injection channel, the sealing member being made of a metal material and being spherical.

2. The cover plate assembly for a battery cell of claim 1, wherein, The inner wall of the liquid injection channel is provided with a groove, and the sealing member abuts against the opening of the groove.

3. The cover plate assembly for a battery cell of claim 1, wherein, The sealing member covers the opening of the groove.

4. The cover plate assembly for a battery cell of claim 1, wherein, The groove is arranged in a plurality of ways along the center line direction of the liquid injection channel.

5. The cover plate assembly for a battery cell of claim 1, wherein, The width of the groove is greater than or equal to 0.01 mm and less than or equal to 0.8 mm; and / or the depth of the groove is greater than or equal to 0.01 mm and less than or equal to 0.8 mm.

6. The cover plate assembly for a battery cell of claim 1, wherein, The diameter of the sealing member is greater than or equal to 2 mm and less than or equal to 6.5 mm.

7. The cover plate assembly for a battery cell of claim 1, wherein, The diameter of the liquid injection hole is greater than or equal to 2 mm and less than or equal to 6 mm; and / or the wall thickness of the liquid injection channel is greater than or equal to 0.1 mm and less than or equal to 0.8 mm.

8. The cover plate assembly for a battery cell of claim 1, wherein, The first end of the liquid injection channel has a first round corner.

9. The cover plate assembly for a battery cell of claim 1, wherein, The second end of the liquid injection channel has a second round corner.

10. A battery cell characterized by, The cover plate and the liquid injection channel are integrally formed. The application relates to a battery cell.

11. A battery module, characterized by The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application relates to a battery cell. The application

Images