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

Abstract

A battery cell cover plate assembly, a battery cell, a battery pack, and a vehicle. The battery cell cover plate assembly comprises a cover plate body (1), a fixing member (2), a first insulating member (3), and a first heat insulation 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 insulation member (4) is arranged between the fixing member (2) and the first insulating member (3).

Description

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

[0001] This application claims priority to the Chinese patent application filed with the Patent Office of China on January 4, 2024, with application number 2024200234427 and invention name "A battery cell cover assembly, battery cell, battery pack and vehicle", the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The embodiments of the present invention relate to, but are not limited to, the field of power battery technology, and specifically, to a battery cell cover assembly, a battery cell, a battery pack, and a vehicle. Background Art

[0003] In new energy vehicles, battery cell production is of vital importance 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 requirements such as reliability, sealing, and insulation 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 member needs to be used between the fixing and the cover body to achieve insulation between the pole and the cover body.

[0004] 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 form 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 part is rapidly 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 fluctuations in the laser power, the insulating parts are prone to heat melting, deformation, etc. If the deformation is too large, the reliability of the cover plate assembly structure may be reduced, and insulation failure may also occur, which will eventually cause the battery cell product to be unqualified. Summary of the Invention

[0005] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0006] An embodiment of the present invention discloses 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.

[0007] Optionally, the battery core further includes an isolation cover, which is provided on a side of the pole core close to the cover plate, and the thermal conductive adhesive is filled between the isolation cover and the cover plate.

[0008] Optionally, the isolation cover is provided with a receiving cavity with an opening toward one side of the cover plate, the thermal conductive adhesive is filled in the receiving cavity, and the cover plate is connected to the isolation cover and in contact with the thermal conductive adhesive.

[0009] Optionally, a glue injection hole is provided on the cover plate, and the glue injection hole is communicated with the accommodating cavity.

[0010] Optionally, a through hole is provided at the bottom of the accommodating cavity, a conductive block is provided at one end of the pole extending into the cover plate, and the pole lug passes through the through hole to be connected to the conductive block.

[0011] Optionally, one end of the tab passes through the through hole and is then bent to form a flange, and the flange is fitted and connected to the conductive block.

[0012] Optionally, the shell is provided with openings at both ends along the length direction, and the two cover plates are respectively covered on the corresponding openings.

[0013] An embodiment of the present invention further discloses a battery cell, comprising the battery cell cover assembly described above.

[0014] An embodiment of the present invention further discloses a battery pack, comprising the battery cell described above.

[0015] An embodiment of the present invention further discloses a vehicle including the above-mentioned battery pack.

[0016] The battery cell cover plate assembly, battery cell, battery pack and vehicle of the embodiment of the present invention have the following beneficial effects: before the pole and the fixing part are fixed, a first thermal insulation part can be added between the first insulating part and the fixing part, and then the pole and the fixing part 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 parts of the multiple battery cells are welded to the bus, due to the presence of the first thermal insulation part, the heat generated by the welding of the fixing part will hardly be transferred to the first insulating part through the first thermal insulation part, thereby ensuring that the first insulating part 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 part, and ultimately improving the pass rate of the battery cell product and even the module.

[0017] Still other aspects will become apparent upon reading and understanding the detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG1 is a first exploded structural diagram of a cell cover assembly of a cell according to an embodiment of the present invention;

[0019] FIG2 is a second exploded structural diagram of a cell cover assembly of a cell according to an embodiment of the present invention;

[0020] FIG3 is a schematic diagram of an exploded structure of a cell cover assembly of another battery cell according to an embodiment of the present invention.

[0021] Explanation of the accompanying drawings: 1. Cover 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

[0022] In order to make the above-mentioned objects, features and advantages of the embodiments of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0023] In the description of the embodiments of the present invention, it should be understood that the terms "upper" and "lower" etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of 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 embodiments of the present invention.

[0024] Furthermore, the Z-axis in the accompanying drawings represents the vertical direction, that is, the up-down direction, with the positive direction of the Z-axis representing the top and the negative direction of the Z-axis representing the bottom. It should also be noted that the aforementioned Z-axis designation is merely for the purpose of facilitating the description of the embodiments of the present invention and simplifying the description, and does not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, it should not be construed as limiting the embodiments of the present invention.

[0025] Referring to Figures 1-3, a battery cell cover assembly according to an embodiment of the present invention 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.

[0026] In this embodiment, compared to conventional cell cover plate assemblies, a first thermal insulation member 4 can be added between the first insulating member 3 and the fixing member 2 before the pole 6 is fixed to the fixing member 2, and then the pole 6 and the fixing member 2 can be fixed. The fixing member 2 can be a rivet block, and the pole 6 can be fixed by riveting to the rivet block.

[0027] When multiple battery cells with 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, and ultimately improving the pass rate of the battery cell products and even the module.

[0028] It should be noted that in the battery cell field, the cross-sectional dimensions of the pole 6 are relatively small, much smaller than those of the fixing member 2, which is typically a riveted aluminum block. Therefore, when assembling a module, the pole 6 is usually not directly welded to the busbar. Instead, the fixing member 2 is welded to the busbar, thereby achieving an indirect electrical connection between the pole 6 and the busbar.

[0029] The first thermal insulation member 4 can be made of mica paper. Mica paper has many advantages, such as being lightweight and thin, which does not increase the weight of the battery cell. Mica paper has excellent high-temperature resistance and can withstand the heat generated by welding the fixing member 2 without damage. Mica paper also has good insulation properties and can act together with the first insulating member 3 to provide insulation, mainly serving to insulate the fixing member 2 from the cover body 1 (usually a plain aluminum sheet, the same material as the battery cell shell). Secondly, mica paper has good processing properties and can be cut, folded, and sewn. It has a certain degree of plasticity, which makes it easy to create a hole structure for the pole 6 to pass through. Mica paper is also easy to install and assemble flexibly, and can be easily assembled with other adjacent components. For example, the first thermal insulation member 4 made of mica paper can be easily installed between the fixing member 2 and the first insulating member 3. Mica paper is a natural material with good environmental performance and will not cause pollution to the environment. It is also relatively cheap and low in cost. In addition, mica paper has a low thermal conductivity coefficient and is commonly available on the market.

[0030] 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.

[0031] In other embodiments, the pole may also be fixed to the fixing member 2 by welding, or even fixed to the fixing member 2 by bolt connection, clamping, etc.

[0032] 1-3 , optionally, the cell cover assembly further includes a second thermal insulation member 5 , which is disposed between the cover body 1 and the first insulating member 3 .

[0033] In this embodiment, before the first insulating member 3 is placed 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 disposed between the cover body 1 and the first insulating member 3. In this way, when the cover body 1 (usually a plain aluminum sheet) is welded to the battery cell housing port, the heat generated by the welding of the cover body 1 is hardly transferred to the first insulating member 3 through the second insulating member 5. This ensures that the first insulating member 3 will not melt or deform during the welding of the cover body 1.

[0034] 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 .

[0035] Of course, in other embodiments, the second thermal insulation member 5 may be a coating of a low thermal conductivity material provided on the surface of the first insulation member 3 , and the coating may be provided on the surface of the first insulation member 3 by spraying.

[0036] Referring to Figures 1-3, optionally, the battery cell cover assembly also includes a pole 6 and a second insulating member 7, and 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.

[0037] 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 . Meanwhile, the second insulating member 7 is required to serve as insulation between the pole 6 and the cover body 1 .

[0038] As shown in Figures 1-3, 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.

[0039] 1-3 , specifically, the cell cover assembly further includes a tab 9, to which the end of the pole 6 away from the second insulating member 7 is welded. In other words, the end of the pole base 61 away from the pole body 62 needs to be welded to the tab 9 to achieve electrical connection between the pole 6 and the tab 9, thereby enabling the battery cell to be electrically connected to an external conductive structure and transmit current.

[0040] 1-3 , optionally, the 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 .

[0041] In this embodiment, in addition to the first and second thermal insulators 4 and 5, a third thermal insulator 8 is also included. As previously described, the end of the pole 6 away from the second insulating member 7 is welded to the tab 9 (i.e., the end of the pole 6 away from the third thermal insulator 8 is welded to the tab 9). This ensures that the heat generated by welding the pole 6 to the tab 9 is virtually non-transmitted to the second insulating member 7 through the third thermal insulator 8, thereby preventing the second insulating member 7 from melting or deforming. The second insulating member 7 can be made of plastic, similar to the first insulating member 3.

[0042] The third thermal insulation member 8 may also be made of mica paper having the above-mentioned advantages.

[0043] Of course, in other embodiments, the third thermal insulation member 8 may be a coating of a low thermal conductivity material provided on the surface of the second insulation member 7, and the coating may be provided on the surface of the second insulation member 7 by spraying.

[0044] Another embodiment of the present invention further provides a battery cell, comprising the battery cell cover assembly as described above.

[0045] Since the technical improvements and technical effects of the battery cell are the same as those of the battery cell cover assembly, the battery cell will not be described in detail.

[0046] 1-2 , a battery cell provided in this embodiment may be an elongated battery cell. The elongated battery cell includes a first housing 10 with openings at both ends, and two battery cell cover assemblies, one for the positive electrode (wherein the electrode 6 is the positive electrode and the tab 9 is the positive tab), and the other for the negative electrode (wherein the electrode 6 is the negative electrode and the tab 9 is the negative tab).

[0047] Referring to 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. In this battery cell cover assembly, the positive electrode column 6 and the negative electrode column are both provided on a cover body 1. It can be understood that the elongated battery cell is longer and thinner than the square battery cell.

[0048] Yet another embodiment of the present invention provides a battery pack, comprising the battery cell as described above.

[0049] Since the battery cell of the embodiment 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.

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

[0051] Since the battery pack of the embodiment of the present invention has higher internal structure reliability, better internal insulation safety and higher product qualification rate, the vehicle equipped with the battery pack also has higher safety and reliability.

[0052] 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.

[0053] Although the embodiments of the present invention are disclosed above, the scope of protection disclosed in the embodiments of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope disclosed in the embodiments of the present invention, and these changes and modifications will fall within the scope of protection of the embodiments of the present invention.

Claims

1. A cell cover plate assembly, comprising 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 disposed between the cover plate body (1) and the fixing member (2), and the first heat insulating member (4) is disposed between the fixing member (2) and the first insulating member (3).

2. The cell cover plate assembly according to claim 1, further comprising a second heat insulating member (5), wherein the second heat insulating member (5) is disposed between the cover plate body (1) and the first insulating member (3).

3. The cell cover plate assembly according to claim 2, further comprising a pole column (6) and a second insulating member (7), wherein the pole column (6) sequentially passes through the second insulating member (7), the cover plate body (1), the second heat insulating member (5), the first insulating member (3), the first heat insulating member (4) and the fixing member (2), and the pole column (6) is fixed to the fixing member (2).

4. The cell cover plate assembly according to claim 3, further comprising a third heat insulating member (8), wherein the third heat insulating member (8) is disposed between the pole column (6) and the second insulating member (7).

5. The cell cover plate assembly according to claim 4, further comprising a tab (9), wherein one end of the pole column (6) away from the third heat insulating member (8) is welded to the tab (9).

6. The cell cover assembly according to claim 4, wherein, The first heat insulating member (4), the second heat insulating member (5) and the third heat insulating member (8) are mica papers respectively.

7. The cell cover assembly according to claim 4, wherein, The first heat insulating member (4) and the second heat insulating member (5) are coatings disposed on the surface of the first insulating member (3), and the third heat insulating member (8) is a coating disposed on the surface of the second insulating member (7).

8. A cell, comprising the cell cover plate assembly according to any one of claims 1-7.

9. A battery pack, comprising the cell according to claim 8.

10. A vehicle, comprising the battery pack according to claim 9.

Images