Battery top cover and battery

Abstract

The utility model relates to the technical field of batteries, and discloses a battery top cover and a battery, the battery top cover comprises a cover plate main body and a thin sheet; the thin sheet is arranged on one side, facing a battery cell, of the cover plate main body, at least the bottom surface, opposite to the cover plate main body, of the thin sheet has insulativity, a groove is formed in one surface, facing the thin sheet, of the cover plate main body, and a liquid injection hole communicated with the groove is formed in one surface, opposite to the thin sheet, of the cover plate main body; a plurality of through liquid inlet holes which are communicated with the groove are formed in the thin sheet; the battery mainly solves the technical problems that the existing battery is low in liquid injection efficiency and easy to overflow outwards in the liquid injection process based on the structural design that the distance between the top cover and the battery cell is relatively small.

Description

Technical Field

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

[0002] With the development of the battery industry, the requirements for energy density of batteries are getting higher and higher. Currently, lithium-ion batteries include a shell, a battery cell and a top cover. The battery cell is housed inside the shell, and the top cover is used to seal the opening on the shell to prevent foreign matter from entering the shell and to prevent the electrolyte inside the shell from flowing out. Among them, the top cover is usually provided with an injection hole. In order to pursue higher battery density, one of the current improvement directions is to shorten the distance between the battery cell and the top cover. When the distance between the top cover and the battery cell is small or even zero, there will be insufficient space inside the battery for the injection hole to enter. During the efficient injection process, there will be a problem of electrolyte overflow, which cannot meet the production requirements of efficient and high-quality injection.

[0003] Therefore, there is a need to improve the existing technology.

[0004] The above information is presented as background information only to assist with an understanding of the present disclosure and is not a determination or admission that any of the above may be applicable as prior art with respect to the present disclosure. Utility Model Content

[0005] The utility model provides a battery top cover and a battery, which mainly solve the technical problems of low liquid injection efficiency and easy overflow during the injection process in the existing battery due to the structural design based on the small distance between the top cover and the battery core.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] A battery top cover comprises a cover plate body and a thin sheet;

[0008] The thin sheet is arranged on the side of the cover body facing the battery cell, and the thin sheet has insulation properties at least on the bottom surface facing away from the cover body. A groove is provided on the side of the cover body facing the thin sheet, and a liquid injection hole connected to the groove is provided on the side of the cover body facing away from the thin sheet. The thin sheet is provided with multiple liquid inlet holes that penetrate and are all connected to the groove.

[0009] In one technical solution, the battery top cover further includes a pole and an explosion-proof valve. The cover body is provided with a first opening and a second opening that penetrate through and are both connected to the groove. The pole is provided at the first opening and is used to connect with the tab. An insulating seal is connected between the pole and the hole wall of the first opening, and the insulating seal is used to insulate and separate the cover body and the pole; the explosion-proof valve is provided at the second opening.

[0010] The thin sheet is provided with a through avoidance hole at a position corresponding to the pole for exposing the pole, and the thin sheet is provided with a through pressure relief hole at a position corresponding to the second opening.

[0011] In one of the technical solutions, a first boss is convexly provided on the bottom of the groove and surrounds the outer periphery of the first opening, and a first gap is formed between the side surface of the first boss and the side wall of the groove, and the thin sheet abuts against the first boss.

[0012] In one of the technical solutions, a second boss is convexly provided on the bottom of the groove and surrounds the outer periphery of the second opening, and a second gap is provided between the side surface of the second boss and the side wall of the groove, and the thin sheet abuts against the second boss.

[0013] In one of the technical solutions, at least one third boss is protruding from the bottom of the groove between the first opening and the second opening, and the thin sheet abuts against the third boss.

[0014] In one of the technical solutions, the groove provides the cover plate body with an annular boss on the side facing the sheet, and the annular boss is arranged around the periphery of the groove, and the outer edges of the sheet are all in contact with the annular boss.

[0015] In one of the technical solutions, the pole and the explosion-proof valve do not extend beyond the bottom surface of the sheet.

[0016] In one of the technical solutions, a lead-out hole is provided on the pole, and the lead-out hole is used to allow the pole lug on the power core to pass through. A protective cover is fixed on the top of the pole, and the protective cover is a conductive metal part, and the protective cover is used to cover the pole lug passing through the lead-out hole.

[0017] In one of the technical solutions, the multiple liquid inlet holes include at least one first hole position and multiple second hole positions, the first hole position is located at a position corresponding to the liquid injection hole, and the multiple second hole positions are spaced apart along the length direction of the cover plate body, and the aperture of the first hole position is larger than the aperture of the liquid injection hole.

[0018] The present application also provides a battery, comprising a shell, a battery cell and a battery top cover as described in any of the above technical solutions, wherein the shell is provided with an opening, the battery cell is accommodated in the shell through the opening, and the cover body seals the opening.

[0019] Compared with the prior art, the battery cover provided by the present invention has at least the following beneficial effects:

[0020] This solution sets a thin sheet on the side of the cover body facing the battery cell, and sets the side of the thin sheet facing away from the cover body to be insulating, so that the cover body will not directly contact the battery cell and cause a short circuit. That is, the top cover of this solution can be as close to the battery cell as possible to shorten the distance between the battery cell and the top cover as much as possible, which is conducive to ensuring a higher energy density. Based on this, this solution sets a groove on the side of the cover body facing the thin sheet, and designs the existing injection hole on the cover body to be connected to the groove, and sets a liquid inlet hole also connected to the groove on the thin sheet, so that during efficient injection, there is enough space inside the battery for the electrolyte to enter the battery, thereby solving the problem of the electrolyte easily overflowing due to insufficient internal space during efficient injection. In fact, after the electrolyte enters from the injection hole, it will flow into the groove, and then flow to the interior of the battery cell below from each liquid inlet hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 A schematic structural diagram of a battery provided in an embodiment of the present application;

[0023] Figure 2 A schematic diagram of the structure of the battery top cover provided in an embodiment of the present application when viewed from above;

[0024] Figure 3 A top view of a battery cover provided in an embodiment of the present application;

[0025] Figure 4 for Figure 3 A local enlarged view of the middle AA;

[0026] Figure 5 for Figure 4 A partial enlarged view of point B in the middle;

[0027] Figure 6 for Figure 4 A partial enlarged view of point C in the middle;

[0028] Figure 7 for Figure 4 A partial enlarged view of point D in the middle;

[0029] Figure 8 This is an exploded view of the structure of the battery top cover provided in an embodiment of the present application when viewed from above;

[0030] Figure 9 for Figure 4 A partial enlarged view of point E in the middle.

[0031] Reference numerals:

[0032] 1. Shell; 11. Opening; 2. Battery cell; 21. Tab; 3. Battery cover;

[0033] 31. Cover plate body; 300. Protrusion; 310. Annular boss; 311. Groove; 312. Injection hole; 313. First opening; 314. Second opening; 315. First boss; 316. Second boss; 317. First gap; 318. Second gap; 319. Third boss; 3100. Fitting hole;

[0034] 32, sheet; 321, liquid inlet; 3211, first hole position; 3212, second hole position; 322, avoidance hole; 323, pressure relief hole;

[0035] 33. Pole; 331. Lead-out hole; 34. Explosion-proof valve; 35. Insulation seal; 36. Protective cover; 37. Protective sheet. DETAILED DESCRIPTION

[0036] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0037] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0038] It should be understood that the terms, "upper", "lower", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0040] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0041] See also Figure 1 The present invention provides a battery comprising a housing 1, a battery cell 2, and a battery cover 3. The housing 1 is provided with an opening 11, through which the battery cell 2 is loaded. The battery cover 3 is primarily used to seal the opening 11 to prevent foreign matter from entering the housing 1 and to prevent the electrolyte within the housing 1 from leaking out. Typically, the battery cover 3 is also used to electrically connect to the tabs 21 extending from the battery cell 2 to externally expose the positive and negative electrodes of the battery cell 2, thereby facilitating the discharge of the battery cell 2 or the charging of the internal battery cell 2.

[0042] Please also refer to Figures 1 to 9 The battery top cover 3 specifically includes a cover body 31 and a thin sheet 32, wherein the cover body 31 is used to seal the above-mentioned opening 11, and the thin sheet 32 is arranged on the side of the cover body 31 facing the battery cell 2 (it can be understood that the thin sheet 32 is arranged at the bottom of the cover body 31), and the thin sheet 32 has insulation at least on the bottom surface facing away from the cover body 31. It can be understood that the thin sheet 32 can only be provided with an insulating pad or insulating paint on the bottom surface facing away from the cover body 31, or the thin sheet 32 can also be a plastic part with insulation. The material of the sheet 32 is preferably PE or PP with good rigidity and insulation. The thickness of the sheet 32 is preferably 1 mm, and a groove 311 is provided on the side of the cover body 31 facing the sheet 32, and a through injection hole 312 is provided on the side of the cover body 31 facing away from the sheet 32 (which can be understood as the top surface of the cover body 31), and this injection hole 312 is downwardly connected to the groove 311. A plurality of through liquid inlet holes 321 are provided on the sheet 32, and these plurality of liquid inlet holes 321 are upwardly connected to the groove 311.

[0043] This section explains the previous section in detail. This solution sets a thin sheet 32 on the bottom of the cover body 31 facing the battery cell 2, and designs the thin sheet 32 as an insulating plastic part, so that the cover body 31 will not directly contact the battery cell 2 and cause a short circuit. That is, the battery top cover 3 of this solution can be as close to the battery cell 2 as possible to shorten the distance between the battery cell 2 and the battery top cover 3 as much as possible, thereby ensuring a higher energy density. Based on this, this solution sets a groove on the side of the cover body 31 facing the thin sheet 32 311, and the existing injection hole 312 on the cover body 31 is designed to be connected to the groove 311, and a liquid inlet hole 321 is provided on the sheet 32 which is also connected to the groove 311, so that during efficient injection, there is enough space inside the battery for the electrolyte to enter the battery, thereby solving the problem of the electrolyte easily overflowing due to insufficient internal space during efficient injection. In fact, after entering from the injection hole 312, the electrolyte will flow into the groove 311, and then flow from each liquid inlet hole 321 to the interior of the battery cell 2 below.

[0044] For more details, please also refer to Figure 2 、 Figure 8 and Figure 9 The multiple liquid inlet holes 321 include at least one first hole position 3211 and multiple second hole positions 3212, wherein the first hole position 3211 is located at a position corresponding to the liquid injection hole 312, and the aperture of the first hole position 3211 is larger than the aperture of the liquid injection hole 312, so as to improve the efficiency of the electrolyte flowing downward into the battery core 2 during liquid injection, thereby ensuring that the electrolyte does not overflow from the liquid injection hole 312 and can meet more efficient liquid injection efficiency; and the multiple second hole positions 3212 are arranged at intervals along the length direction of the cover plate body 31, so that during liquid injection, the electrolyte can diffuse to the surrounding areas in the groove 311 and then flow downward into the battery core 2 more quickly, so as to ensure that the electrolyte does not overflow from the liquid injection hole 312 and can adapt to more efficient liquid injection efficiency. Preferably, a recessed mating hole 3100 can be provided on the top surface of the cover body 31 at the position corresponding to the injection hole 312. The mating hole 3100 is larger than the injection hole 312. The mating hole 3100 is used for inserting the injection nozzle to prevent the electrolyte from overflowing during the injection process.

[0045] Please refer to the Figures 1 to 8The battery top cover 3 also includes a pole 33 and an explosion-proof valve 34, wherein the cover body 31 is provided with a first opening 313 and a second opening 314 that penetrate through the cover body 31. The first opening 313 and the second opening 314 are respectively connected to the groove 311. The pole 33 is provided at the first opening 313. An insulating seal 35 is connected between the pole 33 and the hole wall of the first opening 313. The insulating seal 35 is used to insulate and separate the cover body 31 and the pole 33, and the explosion-proof valve 34 is provided at the second opening 314. Accordingly, the sheet 32 is provided with a through avoidance hole 322 at the position corresponding to the pole 33. During installation, the tab 21 on the battery cell 2 can pass through the avoidance hole 322 and connect with the pole 33, so that the positive or negative pole on the battery cell 2 can be led to the pole 33. In addition, the sheet 32 is provided with a through pressure relief hole 323 at the position corresponding to the second opening 314. When the battery has thermal runaway, the gas inside the battery can pass through the pressure relief hole 323 and break through the explosion-proof valve 34 located in the second opening 314 to release pressure to the outside and prevent the battery from exploding.

[0046] Preferably, if Figures 4 to 6 As shown, the cover body 31 of this embodiment is provided with two first openings 313, and a pole 33 is provided at each of the two first openings 313. One pole 33 is used to connect to the positive terminal tab on the battery cell 2, and the other pole 33 is used to connect to the negative terminal tab on the battery cell 2, so that the battery top cover 3 can simultaneously lead out the positive and negative electrodes of the battery cell 2. In other embodiments, the battery top cover 3 can only lead out the pole 33 of one polarity, and the housing 1 can lead out the pole 33 of the other polarity.

[0047] Please also refer to Figures 4 to 8The bottom of the groove 311 is provided with a first boss 315 and a second boss 316, wherein the first boss 315 is arranged around the periphery of the first opening 313, and the second boss 316 is arranged around the periphery of the second opening 314. The thin sheet 32 abuts against the first boss 315 and the second boss 316 at the same time. By providing the first boss 315 and the second boss 316, the thin sheet 32 can be supported to prevent the thin sheet 32 from being easily deformed upward due to its thin thickness, and ensure that the groove 311 above the thin sheet 32 has enough space for the electrolyte being injected to flow in, so as to ensure that the electrolyte will not overflow from the injection hole 312 under the condition of efficient injection. In addition, a first gap 317 is defined between the side of the first boss 315 and the sidewall of the groove 311, and a second gap 318 is defined between the side of the second boss 316 and the sidewall of the groove 311. The first gap 317 and the second gap 318 ensure that neither the first boss 315 nor the second boss 316 blocks the space within the groove 311. While ensuring sufficient support for the sheet 32, sufficient space is ensured within the groove 311 for the electrolyte being injected, further ensuring that under conditions of efficient injection, the electrolyte does not overflow from the injection hole 312. The provision of the first boss 315 also allows the depth of the first opening 313 to be extended, facilitating the provision of a thicker insulating seal 35, thereby improving the sealing between the terminal 33 and the cover body 31.

[0048] Please refer again Figure 8 At least one third boss 319 may be provided at the bottom of the groove 311 between the first opening 313 and the second opening 314. When the sheet 32 abuts against the third boss 319, it can further prevent the sheet 32 from deforming upward, thereby further ensuring that the groove 311 above the sheet 32 has sufficient space for the electrolyte being injected to flow in, so as to further ensure that the electrolyte will not overflow from the injection hole 312 under the condition of efficient injection. In addition, the groove 311 allows the cover body 31 to be provided with an annular boss 310 arranged around the outer periphery of the groove 311 on the side facing the thin sheet 32 (i.e., the bottom surface of the cover body 31). The outer edges of the thin sheet 32 are all in contact with this annular boss 310, thereby effectively separating the cover body 31 and the battery cell 2 to prevent the battery cell 2 from short-circuiting. At the same time, it also makes the thin sheet 32 less likely to deform under the support of the annular boss 310, thereby further ensuring that the groove 311 above the thin sheet 32 has sufficient space for the electrolyte being injected to flow in, so as to further ensure that the electrolyte will not overflow from the injection hole 312 under the condition of efficient injection.

[0049] Please also refer to Figure 2 、 Figures 4 to 7Because the distance between the sheet 32 and the battery cell 2 in this embodiment is very close, and the sheet 32 can even directly abut the top surface of the battery cell 2, based on this design, the terminal post 33 and the explosion-proof valve 34 in this embodiment are preferably not protruding from the bottom surface of the sheet 32. This prevents the terminal post 33 or the explosion-proof valve 34 from contacting the top surface of the battery cell 2 and causing a short circuit. In other words, the risk of short circuiting is reduced while ensuring the battery has a high energy density. Preferably, in this embodiment, the bottom surface of the terminal post 33 is designed to be flush with the bottom surface of the first boss 315, and the bottom surface of the explosion-proof valve 34 is designed to be flush with the bottom surface of the second boss 316.

[0050] Please also refer to Figure 1 、 Figure 4 、 Figure 5 and Figure 8 The pole 33 is provided with a lead-out hole 331 extending therethrough, and a protective cover 36 is fixed to the top of the pole 33. The protective cover 36 is a conductive metal part. During welding, the tab 21 on the battery cell 2 can first pass upward through the lead-out hole 331. Then, the portion of the tab 21 passing upward through the lead-out hole 331 is bent and welded to the top surface of the pole 33. Finally, the protective cover 36 is placed on the top of the pole 33 and welded to the pole 33. At this time, the protective cover 36 can hide the tab 21 inside to protect the tab 21. At the same time, since the protective cover 36 is conductive, it can conduct the electrical properties of the tab 21 welded to the pole 33. At this time, the protective cover 36 and the pole 33 together constitute a pole assembly. With this design, no space needs to be reserved between the cover body 31 and the battery cell 2 to accommodate the bent tab 21 , thereby shortening the distance between the cover body 31 and the battery cell 2 and further improving the energy density of the battery.

[0051] See also Figure 7 The cover body 31 has a protruding block 300 on the side facing away from the sheet 32 (i.e., the top of the cover body 31). The second hole 3212 passes through the protruding block 300 upward. The protruding block 300 can extend the depth of the second hole 3212 upward, so that a protective sheet 37 can be set in the second hole 3212. The protective sheet 37 is located above the explosion-proof valve 34. The protective sheet 37 is used to protect the explosion-proof valve 34 and prevent it from being ruptured by external force. It ensures that the explosion-proof valve 34 can only rupture and release pressure to the outside after the internal air pressure reaches a threshold, thereby improving the stability and safety of battery use.

[0052] In summary, the battery of this embodiment adopts the above-mentioned battery top cover 3, which can have a higher energy density while meeting the requirements of high-efficiency and high-quality liquid injection, ensuring that the battery can have better production efficiency.

[0053] The above is merely a preferred embodiment of the present invention and only specifically describes the technical principles of the present invention. These descriptions are intended only to explain the principles of the present invention and should not be construed in any way as limiting the scope of protection of the present invention. Based on the explanations herein, any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention, as well as other specific embodiments of the present invention that can be imagined by those skilled in the art without inventive effort, shall be included within the scope of protection of the present invention.

Claims

1. A battery top cover, characterized in that: It comprises a cover plate body (31) and a thin sheet (32); The thin sheet (32) is arranged on the side of the cover plate body (31) facing the battery core, and the thin sheet (32) has insulation properties at least on the bottom surface facing away from the cover plate body (31). The cover plate body (31) is provided with a groove (311) on the side facing the thin sheet (32), and the cover plate body (31) is provided with a liquid injection hole (312) connected to the groove (311) on the side facing away from the thin sheet (32). The thin sheet (32) is provided with a plurality of penetrating liquid inlet holes (321) that are all connected to the groove (311).

2. The battery top cover according to claim 1, wherein: The battery top cover further comprises a pole (33) and an explosion-proof valve (34); a first opening (313) and a second opening (314) are provided on the cover body (31), both of which are penetrated and communicated with the groove (311); the pole (33) is provided at the first opening (313) and is used to be connected to the pole lug; an insulating seal (35) is connected between the pole (33) and the hole wall of the first opening (313); the insulating seal (35) is used to insulate and separate the cover body (31) and the pole (33); the explosion-proof valve (34) is provided at the second opening (314); The thin sheet (32) is provided with a through avoidance hole (322) at a position corresponding to the pole (33) for exposing the pole (33), and the thin sheet (32) is provided with a through pressure relief hole (323) at a position corresponding to the second opening (314).

3. The battery top cover according to claim 2, wherein: A first boss (315) is convexly provided on the bottom of the groove (311) and is arranged around the outer periphery of the first opening (313), and a first gap (317) is provided between the side surface of the first boss (315) and the side wall of the groove (311), and the thin sheet (32) abuts against the first boss (315).

4. The battery top cover according to claim 2, wherein: A second boss (316) is convexly provided on the bottom of the groove (311) and is arranged around the outer periphery of the second opening (314), and a second gap (318) is provided between the side surface of the second boss (316) and the side wall of the groove (311), and the thin sheet (32) abuts against the second boss (316).

5. The battery top cover according to claim 2, wherein: At least one third boss (319) is protruding from the bottom of the groove (311) between the first opening (313) and the second opening (314), and the sheet (32) abuts against the third boss (319).

6. The battery top cover according to claim 1, wherein: The groove (311) enables the cover plate body (31) to be provided with an annular boss (310) on the side facing the thin sheet (32) and surrounding the outer periphery of the groove (311), and the outer edges of the four sides of the thin sheet (32) are all in contact with the annular boss (310).

7. The battery top cover according to claim 2, wherein: The pole (33) and the explosion-proof valve (34) do not extend beyond the bottom surface of the sheet (32).

8. The battery top cover according to claim 2, wherein: The pole (33) is provided with a through lead-out hole (331), and the lead-out hole (331) is used for allowing the pole lug on the power core to pass through. A protective cover (36) is fixed on the top of the pole (33), and the protective cover (36) is a conductive metal part, and the protective cover (36) is used to cover the pole lug passing through the lead-out hole (331).

9. The battery top cover according to any one of claims 1 to 8, characterized in that: The plurality of liquid inlet holes (321) include at least one first hole position (3211) and a plurality of second hole positions (3212), wherein the first hole position (3211) is located at a position corresponding to the liquid injection hole (312), and the plurality of second hole positions (3212) are spaced apart along the length direction of the cover plate body (31), and the aperture of the first hole position (3211) is larger than the aperture of the liquid injection hole (312).

10. A battery, characterized in that: The invention comprises a shell (1), a battery cell (2) and a battery top cover (3) according to any one of claims 1 to 9, wherein the shell (1) is provided with an opening (11), the battery cell (2) is received in the shell (1) through the opening (11), and the cover body (31) seals the opening (11).

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