Battery cover plate, battery, and battery pack

Abstract

The present application relates to the technical field of batteries, and discloses a battery cover plate, a battery, and a battery pack. The battery cover plate comprises: a cover plate body, terminal posts, a first insulating member, and sealing rings; the compressed volume of the sealing rings pressed by the first insulating member is V1, and the compressed volume of the sealing rings pressed by the cover plate body is V2; before the sealing rings are compressed, a first reserved space and a second reserved space are formed, the volume of the first reserved space is V3, and the volume of the second reserved space is V4; the volumes satisfy: 50%≤(V3+V4) / (V1+V2)≤120%, and (V1+V2)≥V3. The present application at least ensures that the first reserved space is completely filled, achieving effective sealing of the battery cover plate; moreover, the present application avoids both permanent deformation of the sealing rings due to excessive compression and deformation of components, such as the first insulating member and the cover plate body, due to excessive compression, and also prevents the first reserved space and the second reserved space from occupying excessive space of the battery cover plate.

Description

Battery cover plate, battery and battery pack

[0001] Cross Reference to Related Applications

[0002] The present application claims priority to the Chinese patent application No. 202410970669.7, filed on July 19, 2024, and entitled "Battery cover plate, battery and battery pack", the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to the technical field of batteries, in particular to a battery cover plate, a battery and a battery pack. BACKGROUND

[0004] With the development and wide use of batteries in the automobile power and energy storage industries, the sealing performance and insulation performance of the battery cover plate play a crucial role. In the battery cover plate, a sealing ring is usually used to fill the gap between the light aluminum plate and the pole to achieve sealing effect and ensure the safety of the battery. In order to achieve effective sealing, the compression of the sealing ring and the filling design of the gap are crucial. SUMMARY

[0005] Therefore, the present application provides a battery cover plate, a battery and a battery pack to solve the problem that the battery cover plate in the prior art cannot achieve effective sealing.

[0006] In a first aspect, the present application provides a battery cover plate, comprising: a cover plate body, provided with a pole hole; a pole, inserted into the pole hole; a first insulating piece, sleeved on the outside of the pole and attached to the upper surface of the cover plate body; a sealing ring, sleeved on the outside of the pole and supported by the pole, the sealing ring has a multi-layer structure along the height direction of the sealing ring, wherein the first layer is located between the outer wall of the pole and the hole wall of the pole hole and is pressed by the first insulating piece, and the inner wall of the second layer is attached to the outer wall of the pole and is pressed by the cover plate body; the compressed volume of the sealing ring pressed by the first insulating piece is V1, and the compressed volume of the sealing ring pressed by the cover plate body is V2; before the sealing ring is compressed, the sealing ring, the first insulating piece and the cover plate body form a first reserved space, and the sealing ring, the lower surface of the cover plate body and one side of the pole supporting the sealing ring form a second reserved space, the volume of the first reserved space is V3, and the volume of the second reserved space is V4; 50%≤(V3+V4) / (V1+V2)≤120%, (V1+V2)≥V3.

[0007] In an alternative embodiment, the battery cover plate further comprises a second insulating member, which is attached to the lower surface of the cover plate body and is located between the lower surface of the cover plate body and the pole, and has a surrounding surface for surrounding the second reserved space.

[0008] In an alternative embodiment, the outer diameter of the layer of the sealing ring pressed by the first insulating member is a, the outer diameter of the layer of the sealing ring pressed by the cover plate body is b, the hole diameter of the pole hole is A, the inner diameter of the second insulating member corresponding to the surrounding surface is B, the inner diameter of the first insulating member is C, the compressed height of the layer of the sealing ring pressed by the first insulating member is h1, the compressed height of the layer of the sealing ring pressed by the cover plate body is h2, the height of the first reserved space is H1, and the height of the second reserved space is H2, which satisfy: V1=π×[(a / 2) 2 -(C / 2) 2 ]×h1, V2=π×[(b / 2) 2 -(A / 2) 2 ]×h2, V3=π×[(A / 2) 2 -(a / 2) 2 ]×H1, and V4=π×[(B / 2) 2 -(b / 2) 2 ]×H2.

[0009] In an alternative embodiment, the second insulating member is inserted between the lower surface of the cover plate body and the surface of the pole supporting the sealing ring, and is spaced apart from the sealing ring before the sealing ring is compressed, the surface of the second insulating member facing the sealing ring forms the surrounding surface, and the sealing ring, the lower surface of the cover plate body, the surrounding surface, and the surface of the pole supporting the sealing ring surround the second reserved space.

[0010] In an alternative embodiment, the sealing ring has at least three layers, the second insulating member is inserted between the lower surface of the cover plate body and the surface of the pole supporting the sealing ring and is in abutment with the third layer of the sealing ring, the surface of the second insulating member in abutment with the sealing ring is spaced apart from the surface of the pole supporting the sealing ring, and the sealing ring, the surface of the second insulating member in abutment with the sealing ring, the surrounding surface, and the surface of the pole supporting the sealing ring surround the second reserved space before the sealing ring is compressed.

[0011] In an alternative embodiment, the sealing ring is of a double-layer structure, and the sealing ring comprises a first ring body and a second ring body which are connected in the height direction, the inner wall of the first ring body and the inner wall of the second ring body are arranged in abutment with the outer wall of the pole, the first insulating member is pressed on the upper side of the first ring body, and the cover body is pressed on the upper side of the second ring body.

[0012] In an alternative embodiment, the battery cover further comprises a riveting block which is arranged in riveting with the outer wall of the pole and is connected with the first insulating member, and the first insulating member is located between the riveting block and the cover body.

[0013] In an alternative embodiment, the pole comprises a first pole segment, a second pole segment and a third pole segment which are connected in the height direction in sequence, the riveting block is arranged in riveting with the outer wall of the first pole segment, the sealing ring is arranged in abutment with the outer wall of the second pole segment, and the third pole segment is supported on the lower surface of the sealing ring.

[0014] In a second aspect, the application further provides a battery comprising the battery cover described above.

[0015] In a third aspect, the application further provides a battery pack comprising the battery described above.

[0016] The application has the following advantages:

[0017] At least the first reserved space can be filled completely in priority, and there is no gap, so that the battery cover is effectively sealed, and the sealing ring is prevented from being permanently deformed due to excessive extrusion, thereby affecting the sealing performance of the battery cover, and the first insulating member and the cover body and other components are prevented from being deformed due to excessive extrusion, thereby causing the local size of the battery cover to be poor and affecting the assembly of the battery cover and the shell, and meanwhile, the first reserved space and the second reserved space do not occupy too much space of the battery cover, so that the space of the battery cover is effectively utilized. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the specific embodiments or the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0019] Fig. 1 is an exploded structural schematic view of a battery cover according to an embodiment of the application;

[0020] Fig. 2 is a top view of a battery cover according to an embodiment of the application;

[0021] Fig. 3 is a schematic view of a sectional structure along the direction of A-A in Fig. 2;

[0022] Fig. 4 is a schematic view of an enlarged structure in Fig. 3;

[0023] Fig. 5 is a schematic view of dimension marking of the structure in Fig. 4;

[0024] Fig. 6 is a schematic view of a partial sectional structure of another battery cover plate according to an embodiment of the present application.

[0025] Legend: 1, cover plate body; 11, pole hole; 12, limiting groove; 2, pole; 21, first pole segment; 22, second pole segment; 23, third pole segment; 3, first insulating member; 4, sealing ring; 41, first ring body; 42, second ring body; 5, first reserved space; 6, second reserved space; 7, second insulating member; 71, enclosing surface; 72, through hole; 8, riveting block. DETAILED DESCRIPTION

[0026] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0027] The embodiments of the present application will be described below in conjunction with Figs. 1 to 6.

[0028] According to the embodiments of the present application, in one aspect, a battery cover plate is provided, which comprises a cover plate body 1, a pole 2, a first insulating member 3 and a sealing ring 4. The cover plate body 1 is provided with a pole hole 11, the pole 2 is inserted into the pole hole 11, the first insulating member 3 is sleeved on the outside of the pole 2 and adheres to the upper surface of the cover plate body 1, and the sealing ring 4 is sleeved on the outside of the pole 2 and is supported by the pole 2. The sealing ring 4 has a multilayer structure along the height direction of the sealing ring 4, wherein the first layer is located between the outer wall of the pole 2 and the hole wall of the pole hole 11 and is pressed by the first insulating member 3, and the inner wall of the second layer is arranged in adhesion with the outer wall of the pole 2 and is pressed by the cover plate body 1. The compressed volume of the sealing ring 4 pressed by the first insulating member 3 is V1, and the compressed volume of the sealing ring 4 pressed by the cover plate body 1 is V2; before the sealing ring 4 is compressed, the sealing ring 4, the first insulating member 3 and the cover plate body 1 enclose a first reserved space 5, and the sealing ring 4, the lower surface of the cover plate body 1 and one side of the pole 2 supporting the sealing ring 4 form a second reserved space 6, the volume of the first reserved space 5 is V3, and the volume of the second reserved space 6 is V4; 50%≤(V3+V4) / (V1+V2)≤120% and (V1+V2)≥V3 are satisfied.

[0029] The battery cover plate of the embodiment can ensure that the first reserved space 5 is filled completely and there is no gap, so as to realize effective sealing of the battery cover plate, avoid permanent deformation of the sealing ring 4 caused by excessive compression, which affects the sealing performance of the battery cover plate, and avoid deformation of the first insulating part 3 and the cover plate body 1 and other components caused by excessive compression, which leads to local size defects of the battery cover plate and affects the assembly of the battery cover plate and the shell. In addition, the first reserved space 5 and the second reserved space 6 do not occupy too much space of the battery cover plate, so as to ensure effective use of the space of the battery cover plate.

[0030] It should be noted that when (V3+V4) / (V1+V2) < 50%, the first reserved space 5 and the second reserved space 6 are filled completely by the compressed sealing ring 4, but the first insulating part 3 and the cover plate body 1 and other components are deformed by excessive compression, which leads to local size defects of the battery cover plate and affects the assembly of the battery cover plate and the shell. In addition, the sealing ring 4 is compressed excessively, which leads to permanent deformation of the sealing ring 4 and affects the sealing performance of the battery cover plate after long-term use. When (V3+V4) / (V1+V2) > 120%, the first reserved space 5 and the second reserved space 6 are too large in volume, which leads to insufficient compression of the sealing ring 4, and further leads to poor sealing and affects the sealing effect of the battery cover plate. In addition, the first reserved space 5 and the second reserved space 6 occupy too much space of the battery cover plate, which is not conducive to the arrangement of other components on the battery cover plate, affects the utilization rate of the space of the battery cover plate, and also affects the structural strength of the battery cover plate. At the same time, (V1+V2) ≥ V3 is ensured to make the first reserved space 5 be filled completely, and further ensure the sealing effect.

[0031] It should be noted that in the embodiment, the height direction of the sealing ring 4 is the thickness direction of the battery cover plate.

[0032] It should be noted that referring to FIG. 4, the volume indicated at the overlapping part of the sealing ring 4 and the first insulating part 3 in FIG. 4 is V1, and the volume indicated at the overlapping part of the sealing ring 4 and the cover plate body 1 in FIG. 4 is V2.

[0033] In one embodiment, as shown in FIGS. 1, 4 and 5, the battery cover plate further comprises a second insulating part 7, which is attached to the lower surface of the cover plate body 1 and located between the lower surface of the cover plate body 1 and the pole 2. The second insulating part 7 has a surrounding surface 71 for surrounding to form the second reserved space 6. By arranging the second insulating part 7, the cover plate body 1 and the pole 2 are insulated, so as to ensure the safety of the battery cover plate.

[0034] In one embodiment, as shown in FIG. 5, the outer diameter of the layer of the sealing ring 4 pressed by the first insulating member 3 is a, the outer diameter of the layer of the sealing ring 4 pressed by the cover plate body 1 is b, the hole diameter of the pole hole 11 is A, the inner diameter of the second insulating member 7 at the corresponding enclosing surface 71 is B, the inner diameter of the first insulating member 3 is C, the compressed height of the layer of the sealing ring 4 pressed by the first insulating member 3 is h1, the compressed height of the layer of the sealing ring 4 pressed by the cover plate body 1 is h2, the height of the first reserved space 5 is H1, and the height of the second reserved space 6 is H2, which satisfy: V1 = π × [(a / 2) 2 -(C / 2) 2 ] × h1, V2 = π × [(b / 2) 2 -(A / 2) 2 ] × h2, V3 = π × [(A / 2) 2 -(a / 2) 2 ] × H1, and V4 = π × [(B / 2) 2 -(b / 2) 2 ] × H2.

[0035] In one embodiment, as shown in FIG. 4, the sealing ring 4 is a double-layer structure, and the sealing ring 4 comprises a first ring body 41 and a second ring body 42 connected in the height direction, the inner wall of the first ring body 41 and the inner wall of the second ring body 42 are both in abutment with the outer wall of the pole 2, the first insulating member 3 is pressed on the upper side of the first ring body 41, and the cover plate body 1 is pressed on the upper side of the second ring body 42.

[0036] In one embodiment, as shown in FIG. 4, the second insulating member 7 is inserted between the lower surface of the cover plate body 1 and the side of the pole 2 supporting the sealing ring 4, the second insulating member 7 is spaced apart from the sealing ring 4 before the sealing ring 4 is compressed, the side of the second insulating member 7 facing the sealing ring 4 forms an enclosing surface 71, and the sealing ring 4, the lower surface of the cover plate body 1, the enclosing surface 71, and the side of the pole 2 supporting the sealing ring 4 enclose to form the second reserved space 6.

[0037] Specifically, as shown in FIG. 1, the second insulating member 7 is provided with a through hole 72, and the part of the second insulating member 7 located at the edge of the through hole 72 is arranged between the lower surface of the cover plate body 1 and the side of the pole 2 supporting the sealing ring 4, and the hole wall of the through hole 72 forms the enclosing surface 71.

[0038] It is worth noting that, in the present embodiment, as shown in FIG. 5, the outer diameter of the first ring body 41 is a, the outer diameter of the second ring body 42 is b, and the inner diameter of the through hole 72 is B; the compressed height of the first ring body 41 is h1, and the compressed height of the second ring body 42 is h2.

[0039] It should be noted that in the embodiment, as shown in FIG. 5, the total height of the sealing ring 4 is H, the height of the second ring body 42 is h, the thickness of the cover plate body 1 is x, the thickness of the portion of the second insulating member 7 located at the edge of the through hole 72 is y, and the following conditions are met: h1=H-x-y; h2=h-y; H1=x+y-h; H2=y.

[0040] It can be understood that those skilled in the art can design the values of the parameters according to the structure of each component of the battery cover plate, so as to meet the requirements of 50%≤(V3+V4) / (V1+V2)≤120% and (V1+V2)≥V3 in the embodiment.

[0041] It should be noted that the first insulating member 3 is the upper plastic, and the second insulating member 7 is the lower plastic.

[0042] Of course, in other alternative embodiments, as shown in FIG. 6, the sealing ring 4 can have a three-layer structure, the second insulating member 7 is inserted between the lower surface of the cover plate body 1 and the side of the pole 2 supporting the sealing ring 4 and is in abutment with the third layer (third ring body) of the sealing ring 4, and the side of the second insulating member 7 in abutment with the sealing ring 4 and the side of the pole 2 supporting the sealing ring 4 are spaced apart. Before the sealing ring 4 is compressed, the sealing ring 4, the side of the second insulating member 7 in abutment with the sealing ring 4, the enclosing surface 71, and the side of the pole 2 supporting the sealing ring 4 enclose to form the second reserved space 6.

[0043] It should be noted that in the above alternative embodiments, the side of the second insulating member 7 in abutment with the sealing ring 4 can be in abutment with the sealing ring 4 before the sealing ring 4 is compressed; or the side of the second insulating member 7 in abutment with the sealing ring 4 can have a gap with the sealing ring 4 before the sealing ring 4 is compressed, and the gap is filled after the sealing ring 4 is compressed.

[0044] It should be noted that in other alternative embodiments, the sealing ring 4 can also have other numbers of layers.

[0045] In one embodiment, as shown in FIG. 4, the battery cover plate further comprises a riveting block 8, the riveting block 8 is in riveting connection with the outer wall of the pole 2 and is in connecting connection with the first insulating member 3, and the first insulating member 3 is located between the riveting block 8 and the cover plate body 1.

[0046] It should be noted that, as shown in FIGS. 1 and 4, the upper surface of the cover plate body 1 is provided with a limiting groove 12, and the first insulating member 3 is located in the limiting groove 12.

[0047] In one embodiment, as shown in FIG. 4, the pole column 2 comprises a first column segment 21, a second column segment 22 and a third column segment 23 which are sequentially connected in the height direction, the riveting block 8 is riveted to the outer wall of the first column segment 21, the sealing ring 4 is fitted to the outer wall of the second column segment 22, and the third column segment 23 is supported on the lower surface of the sealing ring 4.

[0048] The battery cover plates with different ratios of (V3+V4) / (V1+V2) were subjected to metallographic section test, the compression state of the section of the sealing ring 4 and the filling state of the reserved space were observed, and the test results of the battery cover plates of the embodiments are shown in Table 1, and the test results of the battery cover plates of the comparative examples are shown in Table 2. It should be noted that the battery cover plates of the embodiments refer to the battery cover plates satisfying 50%≤(V3+V4) / (V1+V2)≤120% and (V1+V2)≥V3, and the battery cover plates of the comparative examples refer to the battery cover plates not satisfying one or both of 50%≤(V3+V4) / (V1+V2)≤120% and (V1+V2)≥V3. In the embodiments and comparative examples, the sealing ring 4 used in the battery cover plates is made of fluororubber.

[0049] Table 1 Test results of battery cover plates of embodiments

[0050] Table 2 Test results of battery cover plates of comparative examples

[0051] As can be seen from Table 1, in embodiments 1 to 8, the value of (V3+V4) / (V1+V2) is in the range of 50% to 120%, and the value of V1+V2 is greater than the value of V3. The battery cover plates of embodiments 1 to 8 are observed by metallographic method, at least the first reserved space is completely filled with the sealing ring 4, and the upper plastic and the lower plastic are not deformed by extrusion, which all meet the requirements.

[0052] As can be seen from Table 2, in comparative examples 1 to 4, the value of (V3+V4) / (V1+V2) is greater than 120%, so the overall reserved space is too large, which leads to the size of the lower plastic and the cover plate body 1 being too small, which does not meet the requirements. In addition, in comparative examples 1 and 4, the value of V1+V2 is less than the value of V3, which leads to the first reserved space 5 not being filled and having a gap, which does not meet the requirements.

[0053] As can be seen from Table 2, in comparative examples 5 to 8, the value of (V3+V4) / (V1+V2) is less than 50%, and the battery cover plates of comparative examples 5 to 8 are observed by metallographic method, the reserved space is completely filled, and the upper plastic and the lower plastic are deformed by extrusion, which does not meet the requirements.

[0054] It is worth mentioning that when the section metallographic test is carried out, first, the battery cover plate participating in the test is subjected to gel freezing treatment, and the gel is frozen for more than 12 hours at room temperature, then the battery cover plate is cut through the center section of the pole, and the section of the battery cover plate is observed by using the metallographic method to observe the compressed state of the sealing ring 4 and the filling state of the reserved space.

[0055] According to the embodiments of the present application, in another aspect, a battery is also provided, comprising the battery cover plate described above.

[0056] According to the embodiments of the present application, in still another aspect, a battery pack is also provided, comprising the battery described above.

[0057] Although the embodiments of the present application are described in conjunction with the drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.

Claims

1. A battery cover plate, characterized by, The battery cover plate comprises: a cover plate body provided with a pole hole; a pole inserted into the pole hole; a first insulation member sleeved on the outside of the pole and attached to the upper surface of the cover plate body; a sealing ring sleeved on the outside of the pole and supported by the pole, the sealing ring having a multi-layer structure along the height direction of the sealing ring, wherein the first layer is located between the outer wall of the pole and the hole wall of the pole hole and is pressed by the first insulation member, and the inner wall of the second layer is attached to the outer wall of the pole and is pressed by the cover plate body; the compressed volume of the sealing ring pressed by the first insulation member is V1, and the compressed volume of the sealing ring pressed by the cover plate body is V2; before the sealing ring is compressed, the sealing ring, the first insulation member and the cover plate body form a first reserved space, and the sealing ring, the lower surface of the cover plate body and the side of the pole supporting the sealing ring form a second reserved space, the volume of the first reserved space is V3, and the volume of the second reserved space is V4; 50%≤(V3+V4) / (V1+V2)≤120%, (V1+V2)≥V3.

2. The battery cover plate of claim 1, wherein, The battery cover plate further comprises a second insulation member attached to the lower surface of the cover plate body and located between the lower surface of the cover plate body and the pole, the second insulation member having a blocking surface for forming the second reserved space.

3. The battery cover plate of claim 2, wherein, An outer diameter of a layer of the sealing ring pressed by the first insulating piece is a, an outer diameter of a layer of the sealing ring pressed by the cover plate body is b, a hole diameter of the pole hole is A, an inner diameter of the second insulating piece corresponding to the surrounding surface is B, an inner diameter of the first insulating piece is C, a compressed height of the layer of the sealing ring pressed by the first insulating piece is h1, a compressed height of the layer of the sealing ring pressed by the cover plate body is h2, a height of the first reserved space is H1, and a height of the second reserved space is H2, and the following conditions are met: V1=π×[(a / 2) 2 -(C / 2) 2 ]×h1, V2=π×[(b / 2) 2 -(A / 2) 2 ]×h2, V3=π×[(A / 2) 2 -(a / 2) 2 ]×H1, and V4=π×[(B / 2) 2 -(b / 2) 2 ]×H2.

4. The battery cover plate according to claim 2 or 3, characterized in that, The second insulation member is inserted between the lower surface of the cover plate body and the side of the pole supporting the sealing ring, the second insulation member is spaced apart from the sealing ring before the sealing ring is compressed, the side of the second insulation member facing the sealing ring forms the blocking surface, and the sealing ring, the lower surface of the cover plate body, the blocking surface and the side of the pole supporting the sealing ring form the second reserved space.

5. The battery cover plate of claim 2 or 3, wherein, The sealing ring has at least a three-layer structure, the second insulation member is inserted between the lower surface of the cover plate body and the side of the pole supporting the sealing ring and abuts against the third layer of the sealing ring, the side of the second insulation member abutting against the sealing ring is spaced apart from the side of the pole supporting the sealing ring, and the sealing ring, the side of the second insulation member abutting against the sealing ring, the blocking surface and the side of the pole supporting the sealing ring form the second reserved space before the sealing ring is compressed.

6. The battery cover plate of any one of claims 1 to 3, wherein, The sealing ring has a double-layer structure, the sealing ring comprises a first ring body and a second ring body connected along the height direction, the inner wall of the first ring body and the inner wall of the second ring body are both attached to the outer wall of the pole, the first insulation member is pressed on the upper side of the first ring body, and the cover plate body is pressed on the upper side of the second ring body.

7. The battery cover plate of any one of claims 1 to 3, wherein, The battery cover plate further comprises a riveting block riveted to the outer wall of the pole and connected to the first insulation member, and the first insulation member is located between the riveting block and the cover plate body.

8. The battery cover plate of claim 7, wherein, The pole post comprises a first post segment, a second post segment and a third post segment which are sequentially connected in the height direction, the riveting block is riveted with the outer wall of the first post segment, the sealing ring is attached with the outer wall of the second post segment, and the third post segment is supported on the lower surface of the sealing ring.

9. A battery, characterized by A battery cover plate comprising any one of claims 1 to 8.

10. A battery pack, characterized by, A battery comprising claim 9.

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