Battery cell cover plate assembly, battery cell, battery pack and vehicle

Abstract

The utility model provides a battery cell cover plate assembly, a battery cell, a battery pack and a vehicle, and relates to the technical field of power batteries. The battery cell cover plate assembly comprises a cover plate body, a fixing piece, a first insulating piece and a first heat insulation piece, the first insulating piece is arranged between the cover plate body and the fixing piece, and the first heat insulation piece is arranged between the fixing piece and the first insulating piece. Due to the existence of the first heat insulation part, heat generated by the fixing part due to welding is almost not transferred to the first insulation part through the first heat insulation part, so that the condition that the first insulation part is not subjected to hot melting, deformation and the like can be ensured, and the structural reliability of the battery cell cover plate assembly and even the battery cell is ensured; and the insulation effectiveness of the first insulating part is also ensured, and the qualified rate of battery cell products and even modules is finally improved.

Description

Technical Field

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

[0002] In new energy vehicles, battery cell production is crucial and is also one of the main directions of current new energy vehicle development. In the battery cell production and manufacturing process, the assembly of the cover assembly is particularly important for any type of battery cell, and reliability, sealing, insulation and other requirements need to be considered. The cover assembly usually includes a cover body (usually a bare aluminum plate), a pole and a fixing. During the assembly of the cover assembly, the pole passes through the cover body and is fixed to the fixing. For example, the fixing is a rivet block, and the pole is fixed by riveting with the fixing. For insulation requirements, an insulating part is needed between the fixing and the cover body to achieve insulation between the pole and the cover body.

[0003] When the cover plate assembly, or even the entire battery cell, is assembled, it needs to be connected in parallel and / or in series with other battery cells to form a module and finally a battery pack. When the battery cells are connected in parallel and / or in series, it is usually necessary to weld the fixings of multiple battery cells to the bus to achieve indirect electrical connection between the pole and the bus, among which laser welding is a commonly used process method. Laser welding is a non-contact welding method that uses a high-energy-density laser beam as a heat source. During the welding process, the surface of the fixing is quickly heated by high-energy laser radiation. The laser beam power density of laser welding is usually greater than 10,000 W per square centimeter. During the welding process, due to the fluctuation of the laser power, the insulating parts are prone to heat melting, deformation, etc. If the deformation is too large, it may reduce the reliability of the cover plate assembly structure, and may also cause insulation failure problems, which will eventually cause the battery cell product to be unqualified. Utility Model Content

[0004] The utility model aims to improve the product qualification rate of the battery core.

[0005] To solve the above problems, the utility model provides a battery cell cover assembly, including a cover body, a fixing member, a first insulating member and a first thermal insulation member, wherein the first insulating member is arranged between the cover body and the fixing member, and the first thermal insulation member is arranged between the fixing member and the first insulating member.

[0006] Compared with the prior art, the battery cover assembly provided by the utility model has but is not limited to the following technical effects:

[0007] Compared with the traditional battery cell cover plate assembly, a first thermal insulation member can be added between the first insulating member and the fixing member before the pole and the fixing member are fixed, and then the pole and the fixing member can be fixed; when multiple battery cells with the battery cell cover plate assembly need to be connected in series or / and in parallel, that is, when the fixing members of the multiple battery cells are welded to the bus, due to the presence of the first thermal insulation member, the heat generated by the welding of the fixing member will hardly be transmitted to the first insulating member through the first thermal insulation member, thereby ensuring that the first insulating member will not be hot-melted, deformed, etc., thereby ensuring the structural reliability of the battery cell cover plate assembly and even the battery cell, and also ensuring the insulation effectiveness of the first insulating member, ultimately improving the qualified rate of the battery cell products and even the module.

[0008] Furthermore, the battery cell cover plate assembly also includes a second thermal insulation member, and the second thermal insulation member is arranged between the cover plate body and the first insulating member.

[0009] Furthermore, the battery cell cover assembly also includes a pole and a second insulating member, the pole passes through the second insulating member, the cover body, the second thermal insulation member, the first insulating member, the first thermal insulation member and the fixing member in sequence, and the pole is fixed to the fixing member.

[0010] Furthermore, the battery cell cover plate assembly also includes a third thermal insulation member, and the third thermal insulation member is arranged between the pole and the second insulating member.

[0011] Furthermore, the battery cell cover plate assembly also includes a pole ear, and one end of the pole away from the third thermal insulation component is welded to the pole ear.

[0012] Furthermore, the first thermal insulation member, the second thermal insulation member and the third thermal insulation member are respectively mica paper.

[0013] Furthermore, the first thermal insulation member and the second thermal insulation member are coatings disposed on the surface of the first insulation member, and the third thermal insulation member is a coating disposed on the surface of the second insulation member.

[0014] The utility model also provides a battery core, comprising the battery core cover plate assembly as described above.

[0015] Since the technical improvement and technical effect of the battery cell are the same as those of the battery cell cover plate assembly, the battery cell will not be described in detail.

[0016] The utility model also provides a battery pack, comprising the battery core as described above.

[0017] Since the battery cell of the utility model has higher structural reliability and better insulation effectiveness, the battery pack having the battery cell also has higher internal structural reliability, better internal insulation safety and higher product qualification rate.

[0018] The utility model also provides a vehicle, comprising the battery pack as described above. Since the battery pack has higher internal structure reliability, better internal insulation safety and higher product qualification rate, the vehicle with the battery pack also has higher safety and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the exploded structure of a battery cover assembly of a battery cell according to an embodiment of the utility model Figure 1 ;

[0020] Figure 2 Schematic diagram of the exploded structure of a battery cover assembly of a battery cell according to an embodiment of the utility model Figure 2 ;

[0021] Figure 3 The present invention is a schematic diagram of the exploded structure of another battery cover assembly of a battery cell according to an embodiment of the present invention.

[0022] Description of reference numerals:

[0023] 1. Cover plate body; 2. Fixing member; 3. First insulating member; 4. First thermal insulation member; 5. Second thermal insulation member; 6. Pole; 61. Pole base; 62. Pole body; 7. Second insulating member; 8. Third thermal insulation member; 9. Pole ear; 10. First outer shell; 11. Second outer shell. DETAILED DESCRIPTION

[0024] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0025] In the description of the present invention, it is necessary to understand that the terms "upper" and "lower" etc. indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 the present invention.

[0026] Moreover, the Z axis in the drawings represents the vertical direction, that is, the up-down direction, and the positive direction of the Z axis represents the up direction, and the negative direction of the Z axis represents the down direction. It should also be noted that the aforementioned Z axis representation is only for the convenience of describing the present invention and simplifying the description, and does 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 the present invention.

[0027] See also Figure 1-3A battery cell cover assembly according to an embodiment of the utility model includes a cover body 1, a fixing member 2, a first insulating member 3 and a first thermal insulation member 4, wherein the first insulating member 3 is arranged between the cover body 1 and the fixing member 2, and the first thermal insulation member 4 is arranged between the fixing member 2 and the first insulating member 3.

[0028] In this embodiment, compared with the traditional cell cover assembly, before the pole 6 is fixed to the fixing member 2, a first heat insulating member 4 can be added between the first insulating member 3 and the fixing member 2, and then the pole 6 and the fixing member 2 can be fixed. The fixing member 2 can be a riveting block, and the pole 6 can be fixed by riveting with the riveting block.

[0029] When multiple battery cells having the battery cell cover assembly need to be connected in series or / and in parallel, that is, when the fixing parts 2 of the multiple battery cells, such as rivet blocks, are welded to the bus, due to the presence of the first thermal insulation part 4, the heat generated by the welding of the fixing part 2 will hardly be transferred to the first insulating part 3 through the first thermal insulation part 4, thereby ensuring that the first insulating part 3, especially when the first insulating part 3 is a plastic part with a low melting point, will not be hot-melted or deformed, thereby ensuring the structural reliability of the battery cell cover assembly and even the battery cell, and also ensuring the insulation effectiveness of the first insulating part 3, ultimately improving the qualified rate of the battery cell products and even the module.

[0030] It should be noted that in the field of battery cells, since the cross-sectional dimensions of the pole 6 are relatively small, much smaller than the cross-sectional dimensions of the fixing member 2, and the fixing member 2 is usually a riveted block made of aluminum. Therefore, when assembling a module, the pole 6 is usually not directly welded to the bus bar, but the fixing member 2 is welded to the bus bar, thereby achieving indirect electrical connection between the pole 6 and the bus bar.

[0031] Among them, the first heat insulating member 4 can be mica paper, which has many advantages, such as its light texture and will not increase the weight of the battery cell; mica paper has good high temperature resistance and can withstand the heat generated by welding of the fixing member 2 without damage; mica paper also has good insulation performance, which can play an insulating role together with the first insulating member 3, mainly to insulate the fixing member 2 from the cover body 1 (usually a light aluminum sheet, which is made of the same material as the shell of the battery cell). Secondly, mica paper has good processing performance, can be cut, folded, sewn and other processing, has a certain plasticity, and is convenient to open a hole structure for the pole 6 to pass through, and mica paper is easy to install and assemble flexibly, and it is easy to assemble with other adjacent parts. For example, the first heat insulating member 4 made of mica paper is easy to be set between the fixing member 2 and the first insulating member 3; mica paper is a natural material with good environmental performance, will not cause pollution to the environment, and is relatively cheap and low in cost; in addition, mica paper has a low thermal conductivity, is more commonly used on the market, and is easy to obtain.

[0032] Of course, in other embodiments, the first thermal insulation member 4 can be a coating of a low thermal conductivity material provided on the surface of the first insulating member 3, such as a glass fiber layer, and the coating can be provided on the surface of the first insulating member 3 by spraying.

[0033] In other embodiments, the pole may also be fixed to the fixing member 2 by welding, or even by bolt connection, clamping, etc.

[0034] See also Figure 1-3 Optionally, the battery cell cover assembly further includes a second thermal insulation member 5 , and the second thermal insulation member 5 is disposed between the cover body 1 and the first insulating member 3 .

[0035] In this embodiment, before placing the first insulating member 3 on the cover body 1, the second insulating member 5 can be placed on the cover body 1, that is, the second insulating member 5 is provided between the cover body 1 and the first insulating member 3. In this way, when the cover body 1 (usually a bare aluminum sheet) is welded to the shell port of the battery cell, the heat generated by the welding of the cover body 1 will hardly be transferred to the first insulating member 3 through the second insulating member 5, thereby ensuring that when the cover body 1 is welded, the first insulating member 3 will not be melted or deformed.

[0036] Here, the second thermal insulation member 5 can be made of mica paper having the above-mentioned advantages, just like the first thermal insulation member 4 .

[0037] Of course, in other embodiments, the second thermal insulation member 5 may be a coating of a low thermal conductivity material disposed on the surface of the first insulating member 3 , and the coating may be disposed on the surface of the first insulating member 3 by spraying.

[0038] See also Figure 1-3 Optionally, the battery cell cover assembly also includes a pole 6 and a second insulating member 7, the pole 6 passes through the second insulating member 7, the cover body 1, the second thermal insulation member 5, the first insulating member 3, the first thermal insulation member 4 and the fixing member 2 in sequence, and the pole 6 is fixed to the fixing member 2.

[0039] In this embodiment, for the battery cell, the first insulating member 3 serves as insulation between the fixing member 2 and the cover body 1 , and the second insulating member 7 is also required to serve as insulation between the pole 6 and the cover body 1 .

[0040] like Figure 1-3As shown, the pole 6 includes a pole base 61 and a columnar pole body 62. The pole base 61 and the pole body 62 are an integrated structure. When assembling the cover assembly, the end of the pole body 62 away from the pole base 61 passes through the second insulating member 7, the cover body 1, the second thermal insulation member 5, the first insulating member 3, the first thermal insulation member 4 and the fixing member 2 in sequence until the pole base 61 abuts against the second insulating member 7, and then the pole body 62 is fixed to the fixing member 2.

[0041] See also Figure 1-3 Specifically, the cell cover assembly further includes a pole ear 9, and one end of the pole 6 away from the second insulating member 7 is welded to the pole ear 9. That is to say, one end of the pole base 61 away from the pole body 62 needs to be welded to the pole ear 9 to achieve electrical connection between the pole 6 and the pole ear 9, thereby enabling the cell to be electrically connected to the external conductive structure to transfer current.

[0042] See also Figure 1-3 Optionally, the battery cell cover assembly further includes a third thermal insulation member 8 , and the third thermal insulation member 8 is disposed between the pole 6 and the second insulating member 7 .

[0043] In this embodiment, in addition to the first thermal insulation member 4 and the second thermal insulation member 5, a third thermal insulation member 8 is also included. As mentioned above, it is precisely the end of the pole 6 away from the second insulating member 7 that is welded to the pole lug 9 (that is, the end of the pole 6 away from the third thermal insulation member 8 is welded to the pole lug 9), which can ensure that the heat generated by the welding of the pole 6 with the pole lug 9 will hardly be transferred to the second insulating member 7 through the third thermal insulation member 8, thereby ensuring that the second insulating member 7 will not be hot-melted, deformed, etc. Among them, the second insulating member 7 can be the same as the first insulating member 3, both of which are plastic parts.

[0044] The third thermal insulation member 8 may also be made of mica paper having the above-mentioned advantages.

[0045] Of course, in other embodiments, the third thermal insulation member 8 may be a coating of a low thermal conductivity material disposed on the surface of the second insulation member 7, and the coating may be disposed on the surface of the second insulation member 7 by spraying.

[0046] Another embodiment of the present invention further provides a battery cell, comprising the battery cell cover assembly as described above.

[0047] Since the technical improvement and technical effect of the battery cell are the same as those of the battery cell cover plate assembly, the battery cell will not be described in detail.

[0048] See also Figure 1-2In this embodiment, a battery cell can be a long strip battery cell. The long strip battery cell includes a first housing 10 with openings at both ends, and also includes two battery cell cover assemblies, one is a positive battery cell cover assembly (wherein the pole 6 is a positive pole pole 6, and the pole lug 9 is a positive pole lug), and the other is a negative battery cell cover assembly (wherein the pole 6 is a negative pole pole, and the pole lug 9 is a negative pole lug).

[0049] See also Figure 3 Another battery cell provided in this embodiment may be a square battery cell, including a second housing 11 with only one end open, and in the battery cell cover assembly, the positive electrode column 6 and the negative electrode column are both arranged on a cover body 1. It can be understood that the elongated battery cell is longer and thinner than the square battery cell.

[0050] Yet another embodiment of the present invention provides a battery pack, comprising the battery cell as described above.

[0051] Since the battery cell of the present invention has higher structural reliability and better insulation effectiveness, the battery pack having the battery cell also has higher internal structural reliability, better internal insulation safety and higher product qualification rate.

[0052] Yet another embodiment of the present invention provides a vehicle, comprising the battery pack as described above.

[0053] Since the battery pack of the present invention has higher internal structure reliability, better internal insulation safety and higher product qualification rate, the vehicle having the battery pack also has higher safety and reliability.

[0054] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first" and "second" may explicitly or implicitly include at least one of the features.

[0055] Although the utility model is disclosed as above, the protection scope of the utility model is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the utility model, and these changes and modifications will fall within the protection scope of the utility model.

Claims

1. A battery cover assembly, characterized in that: The invention comprises a cover plate body (1), a fixing member (2), a first insulating member (3) and a first heat insulating member (4), wherein the first insulating member (3) is arranged between the cover plate body (1) and the fixing member (2), and the first heat insulating member (4) is arranged between the fixing member (2) and the first insulating member (3).

2. The battery cover assembly according to claim 1, characterized in that: It also comprises a second heat insulating member (5), wherein the second heat insulating member (5) is arranged between the cover plate body (1) and the first insulating member (3).

3. The battery cover assembly according to claim 2, characterized in that: It also includes a pole (6) and a second insulating member (7), wherein the pole (6) passes through the second insulating member (7), the cover body (1), the second thermal insulation member (5), the first insulating member (3), the first thermal insulation member (4) and the fixing member (2) in sequence, and the pole (6) is fixed to the fixing member (2).

4. The battery cover assembly according to claim 3, characterized in that: It also comprises a third heat insulating member (8), wherein the third heat insulating member (8) is arranged between the pole (6) and the second insulating member (7).

5. The battery cover assembly according to claim 4, characterized in that: It also comprises a pole lug (9), and one end of the pole (6) away from the third thermal insulation member (8) is welded to the pole lug (9).

6. The battery cover assembly according to claim 4, characterized in that: The first thermal insulation member (4), the second thermal insulation member (5) and the third thermal insulation member (8) are respectively mica paper.

7. The battery cover assembly according to claim 4, characterized in that: The first thermal insulation member (4) and the second thermal insulation member (5) are coatings provided on the surface of the first insulating member (3), and the third thermal insulation member (8) is a coating provided on the surface of the second insulating member (7).

8. A battery cell, characterized in that: It comprises a battery cell cover plate assembly as described in any one of claims 1 to 7.

9. A battery pack, characterized in that: Comprising the battery cell as claimed in claim 8.

10. A vehicle, characterized in that: Comprising the battery pack as claimed in claim 9.

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