Cover plate structure, battery cell and battery module

Abstract

The invention relates to the technical field of energy storage equipment, in particular to a cover plate structure, a battery cell and a battery module, the cover plate structure comprises a pole, a bottom plate of the pole comprises a fusing safety area and a welding area, a tab is welded to the welding area, a main body of the pole is communicated with the welding area through the fusing safety area, and the fusing safety area can be fused and disconnected during thermal runaway. Therefore, the main body is disconnected from the welding area. The battery cell comprises a battery cell shell and the cover plate structure, the cover plate structure is arranged at the opening of the battery cell shell, and the cover plate structure and the battery cell shell jointly form a battery cell shell. The battery module comprises a module shell and the battery cell, wherein the battery cell is arranged in the module shell. The cover plate structure, the battery cell and the battery module can reduce the internal resistance of the battery cell, reduce the number of accessories, simplify the assembly steps and improve the production efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage equipment, and in particular to a cover plate structure, a battery core and a battery module. Background Art

[0002] The cover of the battery cell is usually equipped with a pole, which is connected to the pole lug of the pole group through a connecting piece. In order to ensure the safety of the battery cell, block the electrical conduction in the event of thermal runaway, delay or even eliminate the risk of thermal runaway, a fuse structure is usually set on the positive pole connecting piece. The fuse structure melts and disconnects in the event of thermal runaway, thus disconnecting the pole group from the pole. However, the connection piece will increase the internal resistance of the battery cell and increase the number of parts. The assembly process requires multiple positioning, which is not conducive to automated production. Summary of the invention

[0003] An object of the present invention is to provide a cover plate structure that can reduce the internal resistance of a battery cell and improve production efficiency.

[0004] To achieve this object, the present invention adopts the following technical solutions:

[0005] A cover plate structure is provided, comprising a pole, wherein the bottom plate of the pole comprises a fuse safety zone and a welding zone, the pole lug is welded to the welding zone, the main body of the pole is connected to the welding zone via the fuse safety zone, and the fuse safety zone can be melted and disconnected in the event of thermal runaway, so that the main body is disconnected from the welding zone.

[0006] Optionally, the fuse safety zone is provided with through holes and / or grooves to reduce the flow cross-section of the fuse safety zone.

[0007] Optionally, an insulating protective layer is further included, and the insulating protective layer is coated on the fuse safety zone.

[0008] Optionally, the cover plate structure further includes a heat sink, which is connected to an area of ​​the welding zone where the pole lug is not welded, and is used to absorb and dissipate the heat of the welding zone.

[0009] Optionally, the heat sink comprises a connection area, the connection area is connected to the end surface of the welding area facing the pole ear, and the end surface of the connection area facing away from the welding area has a heat dissipation protrusion.

[0010] Optionally, the cover plate structure further includes a first plastic part, and the heat sink further includes a heat dissipation area, one end of the heat dissipation area is connected to the connection area, and the other end of the heat dissipation area is bent toward the first plastic part and contacts the first plastic part.

[0011] Optionally, one end of the heat dissipation area connected to the connection area is bent, so that the area where the heat dissipation area is spaced apart from the first plastic part is closer to the first plastic part than the connection area.

[0012] Optionally, the heat sink is a plate-like structure, the thickness of the plate-like structure is T, the plate-like structure has a first plate surface and a second plate surface arranged opposite to each other, the first plate surface faces the first plastic part, the second plate surface faces away from the first plastic part, the area of ​​the second plate surface located in the heat dissipation area is S1, the area of ​​the second plate surface located in the connection area is S3, the surface of the welding area facing the pole ear is the third plate surface, and the area of ​​the third plate surface welded to the pole ear is S2, satisfying , and / or , and / or .

[0013] Another object of the present invention is to provide a battery cell that can reduce the internal resistance of the battery cell and improve production efficiency.

[0014] To achieve this object, the present invention adopts the following technical solutions:

[0015] Provided is a battery cell, comprising a battery cell shell and the above-mentioned cover plate structure, wherein the cover plate structure is arranged at an opening of the battery cell shell, and the cover plate structure and the battery cell shell together form a battery cell outer shell.

[0016] Another object of the present invention is to provide a battery module that can reduce the internal resistance of the battery cell and improve production efficiency.

[0017] To achieve this object, the present invention adopts the following technical solutions:

[0018] A battery module is provided, comprising a module housing and the above-mentioned battery cell, wherein the battery cell is arranged in the module housing.

[0019] Beneficial effects of the present invention:

[0020] The present invention provides a cover plate structure, including a pole, the bottom plate of the pole includes a fuse safety zone and a welding zone, the pole ear is welded to the welding zone, the main body of the pole is connected to the welding zone via the fuse safety zone, and the fuse safety zone can be melted and disconnected in the event of thermal runaway, so that the main body is disconnected from the welding zone. By directly arranging the fuse safety zone and the welding zone on the bottom plate of the pole, the connection sheet can be omitted while ensuring the safe disconnection in thermal runaway, which can not only reduce the internal resistance of the battery cell, but also reduce the number of accessories, simplify the assembly steps, and improve production efficiency.

[0021] The present invention also provides a battery cell, comprising a battery cell shell and the above-mentioned cover plate structure, wherein the cover plate structure is arranged at the opening of the battery cell shell, and the cover plate structure and the battery cell shell together form a battery cell shell. The battery cell can reduce the internal resistance of the battery cell, reduce the number of accessories, simplify the assembly steps, and improve production efficiency.

[0022] The present invention also provides a battery module, comprising a module housing and the above-mentioned battery core, wherein the battery core is arranged in the module housing. The battery module can reduce the internal resistance of the battery core, reduce the number of accessories, simplify the assembly steps, and improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a structural schematic diagram of a cover plate structure provided by an embodiment of the present invention from a first viewing angle;

[0024] Figure 2 is an exploded view of the cover plate structure provided by an embodiment of the present invention from a first perspective;

[0025] Figure 3 is a structural schematic diagram of a cover plate structure provided by an embodiment of the present invention from a second viewing angle;

[0026] Figure 4 is an exploded view of the cover plate structure provided by an embodiment of the present invention from a second viewing angle;

[0027] Figure 5 is a schematic diagram of the structure of a pole provided by an embodiment of the present invention;

[0028] Figure 6 is a structural schematic diagram of a heat sink provided by an embodiment of the present invention from a third viewing angle;

[0029] Figure 7 is a schematic structural diagram of a heat sink provided by an embodiment of the present invention from a fourth viewing angle;

[0030] Figure 8 is a structural schematic diagram of a cover plate structure provided by an embodiment of the present invention from a fifth viewing angle;

[0031] Fig. 9 yes Figure 8 AA section view in;

[0032] Fig.10 is an exploded view of a battery cell (positive electrode and negative electrode are on the same side) provided in an embodiment of the present invention;

[0033] Fig.11 It is an exploded view of a battery cell (positive electrode and negative electrode are on opposite sides) provided in an embodiment of the present invention.

[0034] In the figure:

[0035] 1. Pole; 11. Bottom plate; 111. Fuse safety zone; 1111. First groove; 1112. First through hole; 112. Welding zone; 1121. Third plate surface; 12. Main body;

[0036] 2. Insulation protection layer; 3. Heat dissipation element; 31. Connection area; 311. Heat dissipation protrusion; 32. Heat dissipation area; 321. First bending area; 322. Spacer area; 323. Second bending area; 324. Support end; 301. First board surface; 302. Second board surface;

[0037] 4. First plastic part; 41. Avoidance groove; 42. Limiting protrusion;

[0038] 5. Riveting block; 6. Apply plastic; 7. Sealing ring; 8. Top cover;

[0039] 100. Cover plate structure; 200. Cell shell; 300. Pole group; 3001. Pole ear; 400. Protective sticker. DETAILED DESCRIPTION

[0040] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and implementation methods. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, rather than all of them.

[0041] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0043] The cover plate of the battery cell is generally provided with a pole, which is connected to the pole ear of the pole group through a connecting piece. In order to ensure the safety of the battery cell, block the electrical conduction in the event of thermal runaway, delay or even eliminate the risk of thermal runaway, a fuse structure is generally provided on the connecting piece of the positive electrode, and the fuse structure melts and disconnects in the event of thermal runaway, thereby disconnecting the connection between the pole group and the pole. However, the provision of a connecting piece will increase the internal resistance of the battery cell and increase the number of parts. The assembly process requires multiple positioning, which is not conducive to automated production. In order to solve the above problems, the present embodiment provides a cover plate structure, which can reduce the internal resistance of the battery cell and improve production efficiency.

[0044] like Figures 1 to 9 As shown, the cover plate structure 100 of this embodiment includes a pole 1, the bottom plate 11 of the pole 1 includes a fuse safety zone 111 and a welding zone 112, the pole lug 3001 is welded to the welding zone 112, the main body 12 of the pole 1 is connected to the welding zone 112 via the fuse safety zone 111, and the fuse safety zone 111 can be melted and disconnected in the event of thermal runaway, so that the main body 12 is disconnected from the welding zone 112. By directly arranging the fuse safety zone 111 and the welding zone 112 on the bottom plate 11 of the pole 1, the connecting piece can be omitted under the premise of ensuring safe disconnection in thermal runaway, which can not only reduce the internal resistance of the battery cell, but also reduce the number of accessories, simplify the assembly steps, and improve production efficiency.

[0045] Optionally, the fuse safety area 111 is provided with a through hole. Figure 5 As shown, the fuse safety zone 111 is provided with a first through hole 1112, and the first through hole 1112 is provided through, and the through direction is perpendicular to the plate surface of the bottom plate 11. Since the flow direction of electricity in the bottom plate 11 is parallel to the plate surface direction of the bottom plate 11, the through direction of the first through hole 1112 is perpendicular to the flow direction of electricity, and the opening of the first through hole 1112 can reduce the flow cross section. Of course, in other embodiments, multiple through holes can also be provided, and the multiple through holes can be arranged at intervals, and the through directions are parallel. In addition, the through holes can be arranged to have a cross-section of a circle, an ellipse, a polygon or an irregular shape, which is not limited here.

[0046] Optionally, the fuse safety zone 111 is provided with a groove. Figure 5 As shown, the fuse safety zone 111 is provided with a first groove 1111 to further reduce the flow cross section of the fuse safety zone 111. Optionally, the first groove 1111 is provided on the surface of the bottom plate 11 facing the first plastic part 4, and the first groove 1111 is provided through, and the through direction is perpendicular to the flow direction of electricity.

[0047] Optionally, the cover plate structure 100 further includes an insulating protective layer 2, which is coated on the fuse safety zone 111. The insulating protective layer 2 is used to prevent short circuits and arcing, to provide safety protection for the fuse safety zone 111, and to increase the structural strength of the zone. The first groove 1111 can facilitate positioning when the insulating protective layer 2 is set.

[0048] like Figure 4 As shown, optionally, a side of the first plastic part 4 facing the inside of the battery is provided with an avoidance groove 41, the insulating protective layer 2 is provided protruding from the bottom plate 11, and the protruding portion is located at the avoidance groove 41, so as to prevent the protruding portion of the insulating protective layer 2 from abutting against the first plastic part 4, resulting in a gap between the bottom plate 11 and the first plastic part 4. Optionally, a limiting protrusion 42 is further provided on the side of the first plastic part 4 facing the inside of the battery, and the limiting protrusion 42 is located at the edge of the bottom plate 11, so as to prevent the bottom plate 11 from moving along the plate surface of the first plastic part 4.

[0049] Optionally, the bottom plate 11 of the pole 1 is attached to the surface of the first plastic part 4 facing the inside of the battery, and when the welding area 112 of the bottom plate 11 is welded to the pole lug 3001, the heat will be transferred to the first plastic part 4 through the bottom plate 11, causing the first plastic part 4 to melt and burn to varying degrees. Therefore, it is necessary to dissipate the heat of the pole 1, ensure the heat dissipation efficiency as much as possible within a limited space, dissipate the heat generated by welding, and protect the first plastic part 4. Therefore, optionally, the cover plate structure 100 also includes a heat sink 3, which is connected to the area of ​​the welding area 112 where the pole lug 3001 is not welded, and the heat sink 3 is used to absorb the heat of the welding area 112 and dissipate it.

[0050] Optionally, the heat sink 3 includes a connection area 31, which is connected to the end surface of the welding area 112 facing the pole ear 3001 so that heat can reach the heat sink 3 faster. The end surface of the connection area 31 facing away from the welding area 112 has a heat dissipation protrusion 311 to increase the heat dissipation area of ​​the connection area 31 and improve the heat dissipation efficiency.

[0051] Optionally, the cover plate structure 100 further includes a first plastic part 4, and the heat sink 3 further includes a heat sink 32, one end of the heat sink 32 is connected to the connection area 31, and the other end is bent toward the first plastic part 4 and contacts the first plastic part 4. The provision of the heat sink 32 can further increase the heat dissipation area of ​​the heat sink 3, thereby improving the heat dissipation efficiency. The end of the heat sink 32 contacts the first plastic part 4, which can facilitate the fixation of the heat sink 3, so that the first plastic part 4 can support the heat sink 3.

[0052] Optionally, one end of the heat dissipation area 32 connected to the connection area 31 is bent, so that the area where the heat dissipation area 32 and the first plastic part 4 are spaced apart is closer to the first plastic part 4 than the connection area 31. Such an arrangement can reduce the gap space between the heat dissipation area 32 of the heat dissipation element 3 and the first plastic part 4, reduce the space occupied by heat dissipation, and ensure the energy density of the battery cell.

[0053] Optionally, the heat sink 3 is a bent plate-like structure, and the connection area 31 and the heat dissipation area 32 are arranged in sequence along the length direction of the first plastic part 4, so that the sizes of the connection area 31 and the heat dissipation area 32 of the heat sink 3 can be set larger to ensure sufficient heat dissipation area.

[0054] like Figure 6 and Figure 7 As shown, the heat dissipation area 32 includes a first bending area 321, a spacer area 322, a second bending area 323 and a support end 324 which are sequentially connected along the length direction of the first plastic part 4. The spacer area 322 is a region arranged parallel to the first plastic part 4. The first bending area 321 is located at the connection position between the spacer area 322 and the connection area 31. The second bending area 323 is located between the spacer area 322 and the support end 324. The end surface of the support end 324 contacts the first plastic part 4 to prevent the heat dissipation element 3 from being deformed or displaced by force. The suspended design of the spacer area 322 is conducive to heat dissipation and will not burn the first plastic part 4.

[0055] Optionally, the heat sink 3 is a plate-like structure, the thickness of the plate-like structure is T, satisfying When the heat sink 3 is too thin, the heat dissipation area is too small, and the structural strength of the heat sink 3 cannot be guaranteed. If the spacer 322 is bent and deformed, it may abut against the first plastic part 4, thereby burning the first plastic part 4. If the heat sink 3 is too thick, it will increase the difficulty of bending and occupy more space, which is not conducive to the arrangement of various components inside the battery cell.

[0056] Optionally, the plate-like structure has a first plate surface 301 and a second plate surface 302 arranged opposite to each other, the first plate surface 301 faces the first plastic part 4, the second plate surface 302 faces away from the first plastic part 4, and the area of ​​the second plate surface 302 located in the heat dissipation zone 32 is S1, that is, Figure 6 The area of ​​the shaded area on the left side of the figure is S2, the surface of the welding area 112 facing the pole ear 3001 is the third plate surface 1121, and the area of ​​the portion of the third plate surface 1121 welded to the pole ear 3001 is S2, satisfying That is, it is necessary to ensure that the heat dissipation area of ​​the heat dissipation zone 32 cannot be too small relative to the area of ​​the area on the bottom plate 11 used for welding with the tab 3001, otherwise the heat dissipation effect is not good.

[0057] Optionally, the area of ​​the portion of the second plate surface 302 located in the connection area 31 is S3, that is, Figure 6 The area of ​​the shaded region on the right side of That is, the proportion of the connection area 31 to the heat sink 3 cannot be too small, otherwise the heat conduction area between the heat sink 3 and the bottom plate 11 will be insufficient, and too slow heat transfer will also result in more heat being transferred to the first plastic part 4.

[0058] As shown in Table 1 below, ten different sizes of cover plate structures 100 are provided, and all of the ten cover plate structures 100 adopt the pole 1 and heat sink 3 of the above design, wherein the thickness T of the heat sink 3 is 0.5 mm, and the number of layers of the pole lug 3001 is 90. S4 in the table is the cross-sectional area of ​​the fuse safety zone 111, and the welding power is the welding power when welding between the pole lug 3001 and the pole 1.

[0059] Table 1

[0060]

[0061] The values ​​of the ratio of S1 / S2 of Examples 1, 2 and 3 in the above table are all less than 70%. After the pole ear 3001 is welded to the pole column 1, the first plastic part 4 of the cover plate structure 100 of Example 1 is obviously burned and melted, and the cover plate structure 100 does not meet the use requirements of the battery cell. The first plastic part 4 of the cover plate structure 100 of Example 2 is slightly burned, and the proportion of the cover plate structure 100 that can meet the use requirements of the battery cell is 80%. The first plastic part 4 of the cover plate structure 100 of Example 3 is slightly burned, and the proportion of the cover plate structure 100 that can meet the use requirements of the battery cell is 90%. The values ​​of the ratio of S1 / S2 of Examples 4 to 10 are all greater than or equal to 70%. After the pole ear 3001 and the pole column 1 are welded, the first plastic part 4 of these cover plate structures 100 is not burned, and the proportion of the cover plate structure 100 that can meet the use requirements of the battery cell is 100%.

[0062] As shown in Table 2 below, ten different sizes of cover plate structures 100 are provided, and the ten cover plate structures 100 all adopt the pole 1 and heat sink 3 of the above design, wherein the thickness T of the heat sink 3 is 1 mm, and the number of layers of the pole lug 3001 is 90. Similarly, S4 in the table is the cross-sectional area of ​​the fuse safety zone 111, and the welding power is the welding power when welding between the pole lug 3001 and the pole 1.

[0063] Table 2

[0064]

[0065] The values ​​of the ratio of S3 / S1 in Examples 1, 2, 3, 4 and 5 in the above table are all less than 40%. After the pole lugs 3001 of these cover plate structures 100 are welded to the pole 1, the first plastic part 4 of the cover plate structure 100 of Example 1 is obviously burned and melted, and the cover plate structure 100 does not meet the use requirements of the battery cell. The first plastic part 4 of the cover plate structure 100 of Example 2 is burned, and the proportion of the cover plate structure 100 that can meet the use requirements of the battery cell is 70%. The first plastic part 4 of the cover plate structure 100 of Examples 3 to 5 are all slightly burned, and the proportion of the cover plate structure 100 that can meet the use requirements of the battery cell is 83%, 92% and 99% respectively. The ratio of S3 / S1 in Examples 6 to 10 is greater than or equal to 40%. After the welding of the pole ear 3001 and the pole 1 is completed, the first plastic parts 4 of these cover structures 100 are not burned, and the cover structure 100 can meet the requirements for battery cell use at a ratio of 100%.

[0066] Therefore, in order to prevent the laser welding between the pole ear 3001 and the pole 1 from causing burns or melting of the first plastic part 4, the thickness T of the heat sink 3 must be ensured to meet At the same time, , , to ensure that the first plastic part 4 does not have any burns, thereby ensuring the qualified rate of the product.

[0067] Optionally, in this embodiment, the heat sink 3 is only provided at the positive electrode, and no heat sink 3 is provided at the negative electrode. Of course, in other embodiments, the heat sink 3 may be provided only at the negative electrode, or the heat sink 3 may be provided at both the positive electrode and the negative electrode.

[0068] In this embodiment, the negative pole post 1 is made of copper, which has a higher thermal conductivity, and the negative pole post 1 does not need to be provided with a fuse safety zone 111. Therefore, on the premise that the other dimensions of the negative pole post 1 are consistent with those of the positive pole, the first plastic part 4 will not be burned or melted at the negative pole. Therefore, in this embodiment, the heat sink 3 is only provided at the positive pole.

[0069] Optionally, in this embodiment, the cover structure 100 may only include positive electrode components, that is, the positive electrode and the negative electrode are arranged at both ends of the battery cell, or the cover structure 100 may include both positive and negative electrode components, that is, the positive electrode and the negative electrode are arranged at the same end of the battery cell.

[0070] Optionally, the cover plate structure 100 further includes a rivet block 5, an upper plastic 6, a sealing ring 7 and a top cover 8, wherein the main body 12 of the pole 1 is riveted and fixed to the rivet block 5 through a through hole on the top cover 8, the upper plastic 6 is clamped between the rivet block 5 and the top cover 8, and the sealing ring 7 is sleeved on the main body 12 of the pole 1.

[0071] The cover plate structure 100 of this embodiment adopts the design of the integrated fuse structure of the bottom plate 11 of the pole 1, eliminating parts such as connecting plates. The pole ear 3001 is connected to the bottom plate 11 of the pole 1 by direct welding, which can shorten the length of the pole ear 3001, reduce the process difficulty, and improve the space utilization rate inside the battery cell. The cover plate structure 100 also adds a heat sink 3, which achieves good heat dissipation while ensuring the fuse structure, further improving the safety of the battery cell. And through reasonable size design, the cover plate structure 100 also effectively prevents the first plastic part 4 from being burned or sol-coated due to the heat effect of laser welding between the pole ear 3001 and the pole 1, thereby ensuring the yield of the battery cell.

[0072] like Figure 10 to Figure 11 As shown, this embodiment further provides a battery cell, including a battery cell shell 200 and the above-mentioned cover plate structure 100, the cover plate structure 100 is arranged at the opening of the battery cell shell 200, and the cover plate structure 100 and the battery cell shell 200 together form a battery cell shell.

[0073] Optionally, the battery cell further includes a pole group 300 and a protective sticker 400 , wherein the pole group 300 is disposed in the battery cell housing, and the protective sticker 400 is attached to the outer side of the top cover 8 of the cover plate structure 100 .

[0074] Optionally, the battery cell of this embodiment may be Fig.10 The positive and negative electrodes are on the same side of the battery, or Fig.11 A battery cell is shown with the positive and negative poles on opposite sides.

[0075] The battery cell can reduce the internal resistance of the battery cell, reduce the number of accessories, simplify the assembly steps and improve production efficiency.

[0076] This embodiment also provides a battery module, including a module housing and the above-mentioned battery cell, wherein the battery cell is arranged in the module housing. Optionally, multiple battery cells are arranged in series or in parallel, or partially in series and then in parallel, or partially in parallel and then in series, which is not limited here.

[0077] The battery module can reduce the internal resistance of the battery cell, reduce the number of accessories, simplify the assembly steps and improve production efficiency.

[0078] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. Cover plate structure, characterized in that: The invention comprises a pole (1), wherein a bottom plate (11) of the pole (1) comprises a fuse safety zone (111) and a welding zone (112), a pole lug (3001) is welded to the welding zone (112), a main body (12) of the pole (1) is connected to the welding zone (112) via the fuse safety zone (111), and the fuse safety zone (111) can be melted and disconnected in the event of thermal runaway, so that the main body (12) is disconnected from the welding zone (112).

2. The cover plate structure according to claim 1, characterized in that: The fuse safety zone (111) is provided with a through hole and / or a groove to reduce the flow cross section of the fuse safety zone (111).

3. The cover plate structure according to claim 1, characterized in that: It also comprises an insulating protective layer (2), wherein the insulating protective layer (2) covers the fuse safety area (111).

4. The cover plate structure according to any one of claims 1 to 3, characterized in that: The cover plate structure (100) further comprises a heat sink (3), the heat sink (3) being connected to an area of ​​the welding area (112) to which the pole lug (3001) is not welded, the heat sink (3) being used to absorb and dissipate heat from the welding area (112).

5. The cover plate structure according to claim 4, characterized in that: The heat sink (3) comprises a connection area (31), the connection area (31) being connected to an end surface of the welding area (112) facing the pole ear (3001), and an end surface of the connection area (31) facing away from the welding area (112) having a heat dissipation protrusion (311).

6. The cover plate structure according to claim 5, characterized in that: The cover plate structure (100) further comprises a first plastic part (4), and the heat sink (3) further comprises a heat sink area (32), one end of the heat sink area (32) being connected to the connection area (31), and the other end being bent towards the first plastic part (4) and contacting the first plastic part (4).

7. The cover plate structure according to claim 6, characterized in that: One end of the heat dissipation area (32) connected to the connection area (31) is bent, so that the area where the heat dissipation area (32) and the first plastic part (4) are spaced apart is closer to the first plastic part (4) than the connection area (31).

8. The cover plate structure according to claim 6, characterized in that: The heat sink (3) is a plate-like structure, the thickness of the plate-like structure is T, the plate-like structure comprises a first plate surface (301) and a second plate surface (302) arranged opposite to each other, the first plate surface (301) faces the first plastic part (4), the second plate surface (302) faces away from the first plastic part (4), the area of ​​the portion of the second plate surface (302) located in the heat dissipation zone (32) is S1, the area of ​​the portion of the second plate surface (302) located in the connection zone (31) is S3, the surface of the welding zone (112) facing the pole ear (3001) is a third plate surface (1121), the area of ​​the portion of the third plate surface (1121) welded to the pole ear (3001) is S2, and satisfies , and / or , and / or .

9. A battery cell, characterized in that: It comprises a battery cell shell (200) and a cover plate structure according to any one of claims 1 to 8, wherein the cover plate structure (100) is arranged at an opening of the battery cell shell (200), and the cover plate structure (100) and the battery cell shell (200) together form a battery cell outer shell.

10. A battery module, characterized in that: The invention comprises a module housing and the battery cell as claimed in claim 9, wherein the battery cell is arranged in the module housing.

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