Battery cell cover plate, battery cell and battery pack

Abstract

The utility model provides a battery cell cover plate, battery cell and battery pack wherein the battery cell cover plate comprises a cover plate body, the cover plate body has opposite top surface and bottom surface, and the cover plate body is provided with a liquid injection hole, the liquid injection hole runs through from the top surface to the bottom surface. The bottom surface is used for facing a core package, at least part of the area of the bottom surface is configured to be a flow guide surface, the flow guide surface is adjacent to the liquid injection hole, and the flow guide surface is inclined from the liquid injection hole to the direction far away from the top surface. According to the battery cell cover plate provided by the utility model, the technical problem that the discharge speed of moisture on a cell package is relatively slow when the battery cell is baked can be solved.

Description

Technical Field

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

[0002] In the related art, the battery cell mainly includes a shell, a core pack and a cell cover. The shell includes an installation cavity and a cavity opening connected to the installation cavity. The core pack is installed in the installation cavity. The cell cover is closed at the cavity opening of the installation cavity to seal the core pack. In addition, the battery cell needs to go through a baking process during the production process to remove moisture in the core pack and improve electrical performance and safety.

[0003] However, during baking, since the bottom surface of the battery cover is perpendicular to the rising direction of water vapor, the water vapor will remain on the bottom surface of the battery cover after contacting it, and will not continue to flow to the injection hole and be discharged, resulting in the water vapor being unable to be quickly discharged from the injection hole, and further resulting in the moisture in the core package being unable to dissipate quickly, resulting in low drying efficiency. Utility Model Content

[0004] The embodiments of the utility model provide a battery cover, a battery cell and a battery pack, which can improve the technical problem of slow water discharge speed on the battery pack when the battery cell is baked.

[0005] In the first aspect, an embodiment of the utility model provides a cell cover, the cell cover includes a cover body, the cover body has a top surface and a bottom surface opposite to each other, and a liquid injection hole is provided on the cover body, the liquid injection hole runs from the top surface to the bottom surface. The bottom surface is used to face the core package, and at least a part of the bottom surface is configured as a guide surface, the guide surface is adjacent to the injection hole, and the guide surface is also inclined from the injection hole to the direction away from the top surface.

[0006] In one embodiment, the guide surface is a concave arc surface, the injection hole is located in the guide surface, and the position of the injection hole is closer to the top surface than any position on the guide surface; or, the guide surface is a conical surface, and the injection hole is located at the top of the cone surface.

[0007] In one embodiment, a plurality of the injection holes are provided, and the bottom surface is formed with the guide surface at a position corresponding to each of the injection holes.

[0008] In one embodiment, the cover plate body includes a cover body and an insulating plate fixed on the cover body, the surface of the cover body facing away from the insulating plate forms the top surface, and the surface of the insulating plate facing away from the cover body forms the bottom surface; the injection hole passes through the cover body and the insulating plate, and the bottom surface forms the guide surface at the injection hole.

[0009] In one embodiment, the insulating plate includes a positive insulating plate and a negative insulating plate arranged at intervals, the positive insulating plate has a first bottom surface for facing the core package, the negative insulating plate has a second bottom surface for facing the core package, and the first bottom surface and the second bottom surface together constitute the bottom surface. The injection hole passes through one of the positive insulating plate and the negative insulating plate, a first guide surface is formed on the first bottom surface, and a second guide surface is formed on the second bottom surface, and the first guide surface and the second guide surface together constitute the guide surface. Alternatively, at least one injection hole is passed through the positive insulating plate and the negative insulating plate, respectively, and the first bottom surface and the second bottom surface respectively form the guide surface at the corresponding injection hole.

[0010] In one embodiment, reinforcing bosses are provided on both sides of the bottom surface in the length direction, and the reinforcing bosses have a guide surface for facing the core package, and the guide surface is inclined and has a relative approach side and a distal side; the approach side is closer to the injection hole than the distal side, and the approach side is closer to the top surface than the distal side.

[0011] In one embodiment, a guide groove is further concavely provided on the guide surface, one end of the guide groove is connected to the injection hole, and the other end of the guide groove extends in a direction away from the injection hole.

[0012] In one embodiment, an explosion-proof hole for installing an explosion-proof valve is further concavely provided on the bottom surface, and the guide groove is also connected to the explosion-proof hole.

[0013] In one embodiment, the cover plate body includes a cover body and an insulating plate fixed on the cover body, the surface of the cover body facing away from the insulating plate forms the top surface, and the surface of the insulating plate facing away from the cover body forms the bottom surface; the depth of the guide groove is greater than or equal to one third of the thickness of the insulating plate, and less than or equal to two thirds of the thickness of the insulating plate.

[0014] In the second aspect, an embodiment of the utility model provides a battery cell, which includes a shell, a core pack and a battery cell cover plate as described in any of the above embodiments, the shell has an installation cavity and a cavity opening connected to the installation cavity, the core pack is installed in the installation cavity, and the battery cell cover plate covers the cavity opening.

[0015] In a third aspect, an embodiment of the present utility model provides a battery pack, which includes the battery cell described above.

[0016] Beneficial effects of the embodiments of the utility model:

[0017] In an embodiment of the utility model, by setting at least the bottom surface of the cover body as a guide surface, the guide surface is adjacent to the injection hole, and the guide surface is also inclined from the injection hole to the direction away from the top surface, and then when the rising water vapor flows onto the guide surface, because the guide surface is inclined, the water vapor can continue to flow along the guide surface toward the injection hole, and then be discharged from the injection hole in time to avoid retention, thereby ensuring that the moisture in the core package can be discharged faster, thereby improving the technical problem of slow moisture discharge on the core package when the battery cell is baked. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 It is a three-dimensional schematic diagram of a battery cover provided by an embodiment of the utility model;

[0020] Figure 2 yes Figure 1 A structural cross-sectional view of the cell cover plate;

[0021] Figure 3 yes Figure 2 The structural cross-sectional view of the cell cover at AA;

[0022] Figure 4 It is a structural cross-sectional view of another embodiment of a cell cover provided by an embodiment of the utility model;

[0023] Figure 5 yes Figure 4 A structural cross-sectional view of the cell cover at BB;

[0024] Figure 6 This is a structural cross-sectional view of another embodiment of a cell cover provided by an embodiment of the utility model;

[0025] Figure 7 It is a structural cross-sectional view of an embodiment of a battery cell provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the utility model, and are not used to limit the utility model. In the utility model, unless otherwise stated, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inside" and "outside" refer to the outline of the device.

[0027] like Figure 1 As shown, the utility model of the present application proposes a battery cover 100, which is a key component of the battery 200. For details, please refer to Figure 7 , Figure 7 This is an embodiment of the utility model in which the cell cover plate 100 is assembled with other components into a cell 200, and the cell 200 mainly includes a shell 210, a core package 220 and a cell cover plate 100. The shell 210 is generally made of a metal (such as aluminum, copper, stainless steel, etc.) with good thermal conductivity and mechanical properties to effectively protect the internal structure of the cell 200 (such as the core package 220), and the shell 210 has an installation cavity 211 and a cavity 212 connected to the installation cavity 211.

[0028] The core pack 220 is installed in the installation cavity 211 of the shell 210. The core pack 220 is mainly composed of a positive electrode, a negative electrode and a separator, and the core pack 220 is an important component in the battery cell 200 for generating electrochemical reactions and realizing charging and discharging.

[0029] The cell cover plate 100 covers the cavity opening 212 of the installation cavity 211 to protect the internal structure of the cell 200 and prevent the internal structure of the cell 200 from being damaged by external physical or chemical factors.

[0030] like Figure 1 and Figure 2 As shown, Figure 1 This is a three-dimensional schematic diagram of an embodiment of a battery cover plate of the utility model. Figure 2 for Figure 1 Structural cross-sectional view of the battery cell cover plate. The battery cell cover plate 100 of the present application includes a cover plate body 10, the cover plate body 10 has a bottom surface 12 facing the core package 220 and a top surface 11 opposite to the bottom surface 12, and an injection hole 13 is provided on the cover plate body 10, and the injection hole 13 passes through the top surface 11 and the bottom surface 12.

[0031] Specifically, in this embodiment, the cover body 10 mainly includes a cover body 14 and an insulating plate 15. The cover body 14 can be formed of a plain aluminum sheet, and the insulating plate 15 can be made of plastic. The insulating plate 15 can be fixed to the side of the cover body 14 facing the core package 220 by hot melting. Figure 2 As shown, the side surface of the cover 14 facing away from the insulating plate 15 is the top surface 11, and the side surface of the insulating plate 15 facing away from the cover 14 is the bottom surface 12. When assembling the battery cell 200, you can refer to Figure 7 The bottom surface 12 faces the core package 220 in the shell 210 , and the top surface 11 faces away from the core package 220 .

[0032] The cover body 10 is provided with a liquid injection hole 13, which runs from the top surface 11 to the bottom surface 12. After the cover body 10 is assembled on the shell 210, the liquid injection hole 13 is connected to the installation cavity 211 where the core package 220 is located, so that water vapor can be discharged from the liquid injection hole 13 during baking, and the electrolyte can be injected into the installation cavity 211 after baking. The size, number, and position of the liquid injection hole 13 on the cover body 10 can be flexibly designed according to actual needs and are not specifically limited here.

[0033] Of course, the cover body 10 is generally also equipped with positive pole 18, negative pole 19, explosion-proof valve 17, seals and other components. The specific structure, installation method, function, etc. of these components can refer to the relevant existing technology and will not be introduced in detail here.

[0034] It should be noted that after the shell 210, the core package 220 and the cover body 10 are assembled and before the electrolyte is injected, the battery cell 200 needs to be baked to remove the moisture on the core package 220 and improve the electrical performance and safety of the battery cell. However, in the related art, because the bottom surface of the battery cover is a horizontal plane, which is perpendicular to the rising direction of water vapor, after the water vapor rises and contacts the bottom surface of the battery cover, it will be retained on the bottom surface of the battery cover, and will not continue to flow to the injection hole and be discharged, resulting in the water vapor cannot be quickly discharged from the injection hole, which in turn causes the water in the core package to be unable to quickly dissipate, and the drying efficiency is low.

[0035] Therefore, in order to solve the above technical problems, in the embodiments of the present application, Figure 2 As shown, at least a portion of the bottom surface 12 is configured as a guide surface 121 . The guide surface 121 is adjacent to the liquid injection hole 13 , and the guide surface 121 is inclined from the liquid injection hole 13 to a direction away from the top surface 11 .

[0036] Specifically, the bottom surface 12 may be a portion of the area near the injection hole 13 set as the guide surface 121, or the entire area of ​​the bottom surface 12 may be set as the guide surface 121, which can be flexibly selected according to needs. Figure 2 When the guide surface 121 is provided, the guide surface 121 may be provided only in the left area of ​​the injection hole 13, or only in the right area of ​​the injection hole 13. Figure 3 , Figure 3 for Figure 2 In the structural cross-sectional view of the cell cover at AA, when the guide surface 121 is provided, the guide surface 121 can be provided only in the rear area of ​​the injection hole 13, or only in the front area of ​​the injection hole 13. Alternatively, please combine Figure 2 and Figure 3 The guide surface 121 may be provided in at least two regions of the front, rear, left, and right of the injection hole 13 , and even the guide surface 121 may be provided at any position in the circumferential direction of the injection hole 13 .

[0037] In short, the specific setting method of the guide surface 121 can be determined according to actual conditions. For example, in some embodiments, the position of the injection hole 13 on the cover body 10 is biased to the left side of the cover body 10, and the bottom surface 12 has a larger area in the right area of ​​the injection hole 13. At this time, the guide surface 121 can be set in the right area of ​​the injection hole 13 to guide more water vapor to the injection hole 13.

[0038] The guide surface 121 is adjacent to the injection hole 13, and the guide surface 121 is inclined from the injection hole 13 to a direction away from the top surface 11. Specifically, Figure 2 As shown, the cover body 10 extends horizontally during the baking process of the battery cell 200, and the bottom surface 12 is located below the top surface 11. Therefore, the guide surface 121 is inclined downward relative to the self-injection hole 13. Therefore, when the rising water vapor flows onto the guide surface 121, because the guide surface 121 is inclined, the water vapor can continue to flow along the guide surface 121 toward the injection hole 13, and then be discharged from the injection hole 13 in time to avoid retention, thereby ensuring that the moisture in the core package 220 can be discharged faster, thereby improving the technical problem of slow moisture discharge on the core package 220 when the battery cell 200 is baked.

[0039] It should be noted here that there may be many specific ways for the guide surface 121 to be adjacent to the injection hole 13. For example, in one embodiment, the guide surface 121 is connected to the periphery of the injection hole 13, that is, at least part of the edge of the injection hole 13 on the bottom surface 12 is formed by the edge of the guide surface 121.

[0040] For example, Figure 2As shown, in one embodiment, the cover body 10 includes a cover body 14 and an insulating plate 15 (including a positive insulating plate 151 and a negative insulating plate 152), the injection hole 13 is formed on the cover body 14, and the guide surface 121 is formed on the insulating plate 15. At this time, there may be a certain gap between the guide surface 121 and the edge of the injection hole 13, and the guide surface 121 may be as close to the injection hole 13 as possible during the setting. It should be noted that in this embodiment, because the injection hole 13 is formed on the cover body 14 and the guide surface 121 is formed on the insulating plate 15, an avoidance hole corresponding to the injection hole 13 may be provided on the insulating plate 15, so that the injection hole 13 can extend to the bottom surface 12. At this time, the lower end of the injection hole 13 (i.e., the end close to the core package 220) may be flush with the bottom surface 12, or there may be a certain height difference. For example, in Figure 3 In the structural scheme shown, the lower end of the injection hole 13 protrudes downward relative to the bottom surface 12; Figure 5 In the structural solution shown, the lower end of the liquid injection hole 13 is slightly recessed upward relative to the bottom surface 12.

[0041] Optionally, in one embodiment, please combine Figure 2 and Figure 3 The guide surface 121 is a curved surface and is arranged around the injection hole 13. The injection hole 13 is located closer to the top surface 11 than any position on the guide surface 121. Specifically, in this embodiment, the guide surface 121 is a curved surface similar to a spherical crown surface, and the guide surface 121 is concave toward the side where the top surface 11 is located, so as to Figure 2 and Figure 3 The up and down directions in the figure are taken as reference, so that the bottom surface 12 has a highest point (at Figure 2 and Figure 3 The closer the position is to the top, the higher it is). The injection hole 13 is arranged at the highest point, and thus the injection hole 13 is closer to the top surface 11 than any position on the guide surface 121.

[0042] It can be understood that in this embodiment, the guide surface 121 is arranged around the injection hole 13, and the injection hole 13 is located at the highest position of the guide surface 121. In this way, water vapor from all directions can be gathered into the injection hole 13 and discharged, thereby improving the discharge efficiency of water vapor and further improving the drying efficiency.

[0043] Alternatively, in another embodiment, the guide surface 121 is a conical surface, specifically a circular conical surface or a polygonal conical surface, and the injection hole 13 is located at the top of the cone surface. In this way, water vapor from all directions can be gathered into the injection hole 13 and discharged, thereby improving the discharge efficiency of water vapor.

[0044] Optional, such as Figure 4As shown, in one embodiment, a plurality of injection holes 13 are provided, and a guide surface 121 is formed on the bottom surface 12 at a position corresponding to each injection hole 13. Figure 4 In the structural scheme shown, two injection holes 13 are provided, and the bottom surface 12 forms guide surfaces 121 at the positions of the two injection holes 13, respectively. The formed guide surfaces 121 can be inclined planes, curved surfaces or conical surfaces. For example, the two guide surfaces 121 in the figure are curved surfaces, and the two injection holes 13 are respectively located at the highest positions of the two curved surfaces. It can be understood that in this embodiment, by providing multiple injection holes 13 and forming a guide surface 121 at each injection hole 13, the water vapor in the battery cell 200 can be discharged more quickly.

[0045] Optionally, in one embodiment, as Figure 1 As shown, the cover body 10 includes a cover body 14 and an insulating plate 15 fixed on the cover body 14. The cover body 14 can be a plain aluminum sheet with good heat dissipation performance, and the insulating plate 15 can be made of plastic. Figure 2 As shown, the insulating plate 15 includes a positive insulating plate 151 and a negative insulating plate 152 which are spaced apart. The positive insulating plate 151 is used to connect to the positive pole 18, and the negative pole 19 is used to connect to the negative pole 19, so as to perform corresponding insulation treatment on the positive pole 18 and the negative pole 19 respectively (usually used for insulation between the pole and the cover 14).

[0046] In this embodiment, if Figure 2 As shown, the positive insulating plate 151 has a first bottom surface 122 for facing the core package 220 , and the negative insulating plate 152 has a second bottom surface 123 for facing the core package 220 . The first bottom surface 122 and the second bottom surface 123 together constitute the bottom surface 12 .

[0047] The injection hole 13 passes through one of the positive electrode insulating plate 151 and the negative electrode insulating plate 152. Figure 2 As shown, there is one injection hole 13 on the cover body 10, and the injection hole 13 corresponds to and passes through the positive electrode insulating plate 151. At this time, a first guide surface 1211 is formed on the first bottom surface 122, and a second guide surface 1212 is formed on the second bottom surface 123. The first guide surface 1211 and the second guide surface 1212 together constitute the guide surface 121.

[0048] Specifically, if Figure 2 As shown, the first guide surface 1211 and the second guide surface 1212 are both cambered surfaces, and when the first bottom surface 122 and the second bottom surface 123 respectively form the first guide surface 1211 and the second guide surface 1212, the position of the injection hole 13 is the highest point of the guide surface 121 (with Figure 2The design is based on the principle of "the up and down directions in the figure are used as reference, the closer to the top, the higher the position)", that is, the first guide surface 1211 and the second guide surface 1212 can just form a guide surface 121 with a highest point and a larger area, and the injection hole 13 is located at the highest point of the guide surface 121.

[0049] It can be understood that in this embodiment, when the bottom surface 12 is composed of a first bottom surface 122 and a second bottom surface 123 that are spaced apart, the first guide surface 1211 formed on the first bottom surface 122 and the second guide surface 1212 formed on the second bottom surface 123 together constitute a guide surface 121 with a highest point and a larger area, so that more water vapor can be guided to the injection hole 13, thereby improving the efficiency of water vapor discharge from the battery cell 200.

[0050] In another embodiment, at least one injection hole 13 is respectively formed on the positive electrode insulation plate 151 and the negative electrode insulation plate 152. Figure 4 As shown, Figure 4 This is a structural sectional view of another embodiment of the battery cell cover of the utility model. In this structural scheme, two injection holes 13 are provided, and the two injection holes 13 correspond to the positive electrode insulating plate 151 and the negative electrode insulating plate 152 respectively. At this time, the first bottom surface 122 and the second bottom surface 123 respectively form guide surfaces 121 at their corresponding injection holes 13, so that the water vapor in the battery cell 200 can be discharged more quickly.

[0051] In one embodiment, if Figure 6 As shown, reinforcing bosses 16 are further provided on both sides of the bottom surface 12 in the length direction to strengthen the structural strength of the cover body 10 through the reinforcing bosses 16, and the reinforcing bosses 16 have a guide surface 161 for facing the core package 220, the guide surface 161 is inclined and has a relative approach side 1611 and a distance side 1612, and on the same guide surface 161, the approach side 1611 is closer to the injection hole 13 than the distance side 1612, and the approach side 1611 is closer to the top surface 11 than the distance side 1612.

[0052] That is, with the up and down directions in the figure as a reference, the entire guide surface 161 is inclined upward relative to its distal side 1612, so when the water vapor rises and contacts the guide surface 161 of the reinforcing boss 16, it will flow along the guide surface 161 toward the location of the injection hole 13, thereby guiding more water vapor to the injection hole 13, thereby improving the discharge efficiency of the water vapor.

[0053] In one embodiment, if Figure 1As shown, a guide groove 124 is also concavely provided on the guide surface 121, one end of the guide groove 124 is connected to the injection hole 13, and the other end extends in a direction away from the injection hole 13. Specifically, the end of the guide groove 124 away from the injection hole 13 can extend in any direction, for example, it can extend to a position with more water vapor. It can be understood that compared with the guide surface 121 with a larger area, the space in the guide groove 124 is smaller, so that the water vapor has a stronger directionality when flowing in the guide groove 124, and the water vapor basically does not swing left and right during the flow in the guide groove 124, so that the water vapor can be guided to the injection hole 13 faster, thereby improving the discharge efficiency of the water vapor.

[0054] It should be noted here that the extension length, cross-sectional shape, number, etc. of the guide groove 124 can be flexibly designed as needed. For example, there can be multiple guide grooves 124, and the guide groove 124 extends from the injection hole 13 to the edge of the guide surface 121 to guide more water vapor to the injection hole 13 faster.

[0055] Furthermore, in one embodiment, if Figure 1 As shown, an explosion-proof hole 125 for installing an explosion-proof valve 17 is also recessed on the bottom surface 12, and the guide groove 124 is also connected to the explosion-proof hole 125, so that the water vapor in the explosion-proof hole 125 can be guided to the injection hole 13 through the guide groove 124 and discharged, avoiding the water vapor from being retained in the explosion-proof hole 125.

[0056] As for the depth of the guide groove 124, in one embodiment, the cover body 10 includes a cover body 14 and an insulating plate 15 fixed on the cover body 14, the surface of the cover body 14 facing away from the insulating plate 15 forms a top surface 11, and the surface of the insulating plate 15 facing away from the cover body 14 forms a bottom surface 12, and the depth of the guide groove 124 is greater than or equal to one-third of the thickness of the insulating plate 15, and less than or equal to two-thirds of the thickness of the insulating plate 15. It can be understood that if the depth of the guide groove 124 is too small, the effect of rapid diversion is not obvious enough, and if the depth of the guide groove 124 is too large, it will affect the structural strength and insulation effect of the insulating plate 15. Therefore, in this embodiment, by making the depth of the guide groove 124 greater than or equal to one-third of the thickness of the insulating plate 15, and less than or equal to two-thirds of the thickness of the insulating plate 15, it can avoid affecting the structural strength and insulation effect of the insulating plate 15 while achieving rapid diversion.

[0057] Second, as Figure 7As shown, an embodiment of the utility model provides a battery cell 200, the battery cell 200 includes a shell 210, a core pack 220 and a battery cell cover 100, the shell 210 has an installation cavity 211 and a cavity 212 connected to the installation cavity 211, the core pack 220 is installed in the installation cavity 211, the battery cell cover 100 covers the cavity 212, and the specific structure of the battery cell cover 100 refers to any of the above embodiments. Since the battery cell 200 of the present application adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0058] On the third aspect, an embodiment of the utility model provides a battery pack (not shown), which can be used in electric equipment such as automobiles, and the battery pack includes the battery cell 200 described above, and the battery pack includes a plurality of battery cells 200, and the plurality of battery cells 200 are arranged in a matrix of multiple rows and columns.

[0059] The above is a detailed introduction to the embodiments of the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for technicians in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A battery cell cover, characterized in that: include: A cover plate body, the cover plate body having a bottom surface facing the core package and a top surface opposite to the bottom surface, the cover plate body being provided with a liquid injection hole, the liquid injection hole penetrating the top surface and the bottom surface; At least a portion of the bottom surface is configured as a guide surface, the guide surface is adjacent to the liquid injection hole, and the guide surface is also inclined from the liquid injection hole to a direction away from the top surface.

2. The cell cover plate according to claim 1, characterized in that: The guide surface is an arc surface and is arranged around the injection hole, and the position of the injection hole is closer to the top surface than any position on the guide surface; or, the guide surface is a conical surface, and the injection hole is located at the top of the conical surface.

3. The cell cover plate according to claim 2, characterized in that: The liquid injection holes are provided in plurality, and the bottom surface is formed with the guide surface at a position corresponding to each of the liquid injection holes.

4. The battery cover according to claim 2, characterized in that: The cover body comprises a cover body and an insulating plate fixed on the cover body, the surface of the cover body away from the insulating plate forms the top surface, and the surface of the insulating plate away from the cover body forms the bottom surface; The injection hole passes through the cover body and the insulating plate, and the bottom surface forms the guide surface at the injection hole.

5. The cell cover plate according to claim 4, characterized in that: The insulating plate comprises a positive insulating plate and a negative insulating plate, the positive insulating plate has a first bottom surface for facing the core package, the negative insulating plate has a second bottom surface for facing the core package, and the first bottom surface and the second bottom surface together constitute the bottom surface; The injection hole passes through one of the positive electrode insulating plate and the negative electrode insulating plate, a first guide surface is formed on the first bottom surface, a second guide surface is formed on the second bottom surface, and the first guide surface and the second guide surface together constitute the guide surface; Alternatively, at least one injection hole is respectively passed through the positive electrode insulation plate and the negative electrode insulation plate, and the first bottom surface and the second bottom surface form the guide surfaces at the corresponding injection holes.

6. The cell cover plate according to any one of claims 1 to 5, characterized in that: The bottom surface is also provided with reinforcing bosses on both sides in the length direction, and the reinforcing bosses have a guide surface for facing the core package, and the guide surface is inclined and has a relative approach side and a distance side; The proximal side is closer to the liquid injection hole than the distal side, and the proximal side is closer to the top surface than the distal side.

7. The cell cover plate according to any one of claims 4 to 5, characterized in that: The guide surface is also concavely provided with a guide groove, one end of which is connected to the injection hole, and the other end of which extends in a direction away from the injection hole.

8. The cell cover plate according to claim 7, characterized in that: The bottom surface is also concavely provided with an explosion-proof hole for installing an explosion-proof valve, and the guide groove is also connected to the explosion-proof hole.

9. The cell cover plate according to claim 7, characterized in that: The depth of the guide groove is greater than or equal to one third of the thickness of the insulation plate, and less than or equal to two thirds of the thickness of the insulation plate.

10. A battery cell, characterized in that: It comprises a shell, a core pack and a cell cover plate as described in any one of claims 1 to 9, wherein the shell has an installation cavity and a cavity opening connected to the installation cavity, the core pack is installed in the installation cavity, and the cell cover plate covers the cavity opening.

11. A battery pack, characterized in that: Comprising the battery cell as claimed in claim 10.

Images