Battery cell cover plate and battery cell
By designing vent holes and boss structures on the battery cover, combined with connecting holes in the support and insulation components, the problem of the electrode group blocking the explosion-proof valve during thermal runaway is solved, realizing safe venting of the battery cell and improving safety performance.
Patent Information
- Application Number
- CN202423209352.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-24
- Publication Date
- 2026-01-30
- Estimated Expiration
- 2034-12-24
AI Technical Summary
In existing lithium-ion batteries, the lower plastic layer is prone to melting during thermal runaway, which increases the gap between the electrode assembly and the cover plate and casing, obstructs the explosion-proof valve, reduces the venting effect, and affects the safety performance of the cell.
Vent holes are made on the main body of the cover plate, and a boss is formed facing the inside of the cell. The support member is spaced apart from the cover plate. A first connecting hole is made on the support member, and a second connecting hole is made on the insulating member to form insulation protection and ensure smooth venting.
Even if the electrode assembly shifts inside the cell, the support structure can prevent the electrode assembly from blocking the vent, ensuring smooth venting in case of thermal runaway and improving the cell's safety performance.
Smart Images
Figure CN223858258U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to battery technology field especially is related to a kind of battery cell cover plate and battery cell. BACKGROUND
[0002] Lithium ion battery is widely used in traffic power supply, power storage power supply, new energy storage power supply, aerospace military industry and other fields due to its advantages of large capacity, high working voltage, strong charge retention ability and long cycle life.
[0003] Long battery cell lithium ion battery includes: cover plate, shell, bare battery cell insulating film, pole group, electrolyte etc. Cover plate and shell are welded, and constitute the closed space with certain mechanical strength to protect pole group;Pole group is fixed by welding with pole lug and pole post base on cover plate, to realize electrical connection;Bare battery cell insulating film is wrapped around pole group and is fixed with lower plastic on both sides of cover plate respectively, to ensure that pole group is isolated from shell;Explosion-proof valve structure is integrated on cover plate, for directional discharge of internal high temperature and high pressure gas when battery appears thermal runaway.
[0004] At present, pole group is mainly insulated and fixed by lower plastic in length direction, and lower plastic is generally made of pp (polypropylene) material, which has much smaller strength and high temperature resistance than temperature when thermal runaway occurs. At least part of lower plastic is melted when thermal runaway occurs, which leads to the increase of gap between pole group and cover plate and shell. Since high temperature and high pressure gas is discharged in the direction of explosion-proof valve, pole group will block explosion-proof valve on cover plate due to the movement of high temperature and high pressure gas stream, which greatly reduces the exhaust effect of explosion-proof valve and the safety performance of battery cell. INVENTION CONTENTS
[0005] Therefore, the purpose of the present application is to provide a battery cell cover plate and battery cell to solve the problem that at least part of the lower plastic is easy to melt when thermal runaway occurs, which leads to the increase of gap between pole group and cover plate and shell, and pole group will block explosion-proof valve on cover plate due to the movement of high temperature and high pressure gas stream, which reduces the exhaust effect of explosion-proof valve and the safety performance of battery cell.
[0006] The utility model discloses a battery cell cover plate in a first aspect, wherein the battery cell cover plate comprises:
[0007] Cover plate main body, which is provided with an exhaust hole, and a boss protruding towards the inside of the battery cell is formed on the cover plate main body;
[0008] Pressure relief component installed in the exhaust hole;
[0009] Supporting component is arranged on the surface of the boss away from the cover plate main body, so that the supporting component is arranged apart from the cover plate main body, and a first communication hole is formed on the supporting component;
[0010] An insulating piece is arranged on the side of the cover plate body facing the inside of the battery cell, the support piece is clamped between the cover plate body and the insulating piece, and a second communication hole is formed in the insulating piece.
[0011] Preferably, a plurality of bosses are arranged around the exhaust hole.
[0012] Preferably, the total area of the projection of the boss on the cover plate body is 400mm 2 to 900mm 2 .
[0013] Preferably, the first communication hole has a hole size d1, and 1.2mm≤d1≤2.5mm.
[0014] Preferably, the second communication hole has a hole size d2, and 2.5mm≤d2≤4mm.
[0015] Preferably, the height of the boss in the thickness direction of the cover plate body is H1, and 1mm≤H1≤2mm.
[0016] Preferably, the cover plate body is formed in a plate structure, and the support piece is formed in a plate structure arranged parallel to the cover plate body.
[0017] The thickness of the support piece is H2, and 0.8mm≤H2≤1.5mm.
[0018] Preferably, a plurality of first communication holes are arranged in an array on the support piece.
[0019] And / or, a plurality of second communication holes are arranged in an array on the insulating piece.
[0020] Preferably, further comprising:
[0021] A protective piece is arranged on the side of the cover plate body facing the outside of the battery cell, and the protective piece covers part of the exhaust hole.
[0022] The second aspect of the utility model provides a battery cell comprising the battery cell cover of any of the above technical solutions.
[0023] Compared with the prior art, the utility model has the beneficial effects that:
[0024] The utility model discloses an electric core cover plate, set up on the cover plate main part exhaust hole, and form the boss that protrudes to the electric core inside, support spare setting on the surface of the boss away from the cover plate main part, make support spare and the cover plate main part interval setting, even if the pole group appears the displacement in the electric core inside, support spare can form the block to the pole group, avoid appearing the pole group will exhaust hole shield even is the situation of complete plugging, guarantee under the condition of thermal runaway can smoothly exhaust.
[0025] In order to make the above-mentioned purpose, features and advantages of the present application more obvious and easy to understand, the following preferred embodiments are specifically described below, and the accompanying drawings are described in detail as follows. BRIEF DESCRIPTION OF DRAWINGS
[0026] In order to more clearly illustrate the specific embodiment of the utility model or the technical scheme in the prior art, the following will be briefly introduced the drawings needed to be used in the specific embodiment or prior art description, obviously, the following description in the drawings is some embodiments of the utility model, for those skilled in the art, without creative labor, according to these drawings, other drawings can also be obtained.
[0027] Figure 1 The structure diagram of the separation of the insulating part and the cover plate main body in the electric core cover plate provided by the embodiment of the utility model is shown.
[0028] Figure 2 The structure explosion map of the electric core cover plate provided by the embodiment of the utility model is shown.
[0029] Figure 3 The structure diagram of the cover plate main body in the electric core cover plate provided by the embodiment of the utility model is shown.
[0030] Figure 4 The structure diagram of the support spare installation on the boss in the electric core cover plate provided by the embodiment of the utility model is shown.
[0031] Icon: 10-cover plate main part;11-exhaust hole;12-boss;20-support spare;21-first communication hole;30-insulating part;31-second communication hole;40-pressure relief part;50-protection part. DETAILED DESCRIPTION
[0032] The following detailed description is presented to aid the reader in gaining a comprehensive understanding of the methods, apparatuses, and / or systems described herein. However, various changes, modifications, and equivalents can be used, and thus particular embodiments described herein are not intended as being exhaustive of what the present disclosure can provide. For example, although processes are described with regard to the present disclosure, such processes can include more, fewer, or only a single process. Additionally, some processes can not be implemented even though they are described. Moreover, although processes are described herein as various separate processes, which can be performed by different systems, such processes can not necessarily be performed by different systems and the order of some processes can be changed, including that certain processes could be performed in an iterative or parallel manner. Additionally, various features that are described herein can be implemented as hardware, software, firmware, or combinations thereof, and can be implemented within one or more processors or external to one or more processors, including being implemented across multiple processors. Further, it will be appreciated that features described herein as being implemented with or across one or more processors can be implemented by one or more other processors.
[0033] The features described herein can be implemented in different forms and are not to be construed as limited to the examples described herein. Rather, the described examples have been provided for illustrative purposes so that those skilled in the art will be able to implement the methods, apparatuses, and / or systems described herein in a variety of ways.
[0034] Throughout the specification, when an element (such as a layer, region, or substrate) is referred to as being “on” another element, “connected to” another element, “coupled to” another element, “in contact with” another element, or “covering” another element, it can be directly on, connected, coupled, in contact with, or covering the other element, or one or more other elements can be interposed therebetween. In contrast, when an element is referred to as being “directly on,” “directly connected to,” “directly coupled to,” “directly in contact with,” or “directly covering” another element, there are no other elements interposed therebetween.
[0035] As used herein, the term “and / or” includes any one of the listed items and any combination of any two or more of the listed items.
[0036] Although terms such as “first,” “second,” and “third” can be used herein to describe various elements, components, regions, layers, or sections, these elements, components, regions, layers, or sections are not limited by these terms. Rather, these terms are only used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, the element, component, region, layer, or section referred to as the first element, component, region, layer, or section in the examples described herein can also be referred to as the second element, component, region, layer, or section without departing from the teachings of the examples.
[0037] For ease of description, spatially relative terms, such as "on", "upper", "lower", "above", and "below", can be used herein for the purpose of illustrating one element's relationship to another element in the drawings. Such spatially relative terms are intended to encompass different orientations of the device in use or operation, in addition to the orientations depicted in the drawings. For example, if the device in the drawings is turned over, elements described as being "on" or "above" other elements would then be oriented "below" or "under" the other elements. Thus, the term "on" can encompass both an "on" and "under" position depending on the spatial orientation of the device. The device can be oriented in other ways (for example, rotated 90 degrees or at other orientations) and the spatially relative terms used herein are interpreted accordingly.
[0038] The terminology used herein is for the purpose of describing various examples only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", "includes", "including" and "has", "having" as used herein, are specifically intended to be construed as open-ended terms (i.e., the terms do not exclude the presence of other elements or options).
[0039] Variations in shapes depicted in the drawings can occur as a result of manufacturing processes and / or tolerances. Thus, the examples described herein are not limited to the precise shapes shown in the drawings, but include variations in shapes that would result from the manufacturing process used to produce the drawings.
[0040] Features of the examples described herein can be combined with one another as would be apparent to one of ordinary skill in the art after having the benefit of the present disclosure. Furthermore, although examples described herein have a variety of configurations, other configurations are possible in which are apparent after having the benefit of the present disclosure.
[0041] According to a first aspect of the present application, there is provided an electric core cover plate, which specifically comprises a cover plate body 10, a pressure relief member 40, a support member 20, and an insulating member 30.
[0042] Hereinafter, the specific structure of the electric core cover plate according to the present embodiment will be described.
[0043] In the present embodiment, as Figures 1 to 4As shown, the cover plate body 10 is formed as a plate structure, when the battery cell is a square shell battery cell or a blade battery cell, the cover plate body 10 is formed as a rectangular plate structure, when the battery cell is a cylindrical battery cell, the cover plate body 10 is formed as a circular plate structure, the cover plate body 10 is a metal piece, the cover plate body 10 is provided with an exhaust hole 11, the exhaust hole 11 is a through hole structure penetrating through the cover plate body 10, so that the inside and outside of the battery cell are communicated, in this way, when the battery cell is in thermal runaway, the gas in the battery cell can be discharged to the outside of the battery cell, the pressure relief piece 40 is installed on the exhaust hole 11, the pressure relief piece 40 can be an explosion-proof valve, under normal circumstances, the pressure relief piece 40 closes the exhaust hole 11, when the internal pressure of the battery cell increases to the opening pressure of the pressure relief piece 40 due to thermal runaway, the pressure relief piece 40 will open to achieve pressure relief.
[0044] In the embodiment, as shown in Figures 1 to 3 , a boss 12 protruding towards the inside of the battery cell is formed on the cover plate body 10. In an optional embodiment, the boss 12 is formed on the cover plate body 10 by stamping. The support piece 20 is arranged on the surface of the boss 12 away from the cover plate body 10, so that the support piece 20 is arranged spaced apart from the cover plate body 10, the insulating piece 30 is arranged on the side of the cover plate body 10 facing the inside of the battery cell, and the support piece 20 is clamped between the cover plate body 10 and the insulating piece 30, so that the insulating piece 30 can separate the cover plate body 10 and the pole group in the battery cell to form insulation protection. The insulating film wrapped outside the pole group can be heat-fused with the insulating piece 30 to fix the pole group and the battery cell cover plate. Even if at least part of the insulating piece 30 melts and causes the pole group to displace in the battery cell during thermal runaway, the support piece 20 can block the pole group to avoid the pole group from blocking or even completely blocking the exhaust hole 11, thereby ensuring smooth exhaust during thermal runaway.
[0045] Preferably, as shown in Figure 1 and Figure 3 , the boss 12 can be formed as a block structure, so that after the support piece 20 is installed on the boss 12, the gas in the battery cell can not only flow from the first communication hole 21 to the exhaust hole 11, but also flow from the channel formed by the support piece 20, the boss 12 and the cover plate body 10 to the exhaust hole 11, to ensure smooth exhaust.
[0046] In the embodiment, as shown in Figures 1 to 4 , the support piece 20 is provided with a first communication hole 21, and the insulating piece 30 is provided with a second communication hole 31, the diameter of the second communication hole 31 is larger than the diameter of the first communication hole 21, so that the area of each second communication hole 31 is larger than the area of each first communication hole 21, to ensure smooth exhaust and protection. The first communication hole 21 and / or the second communication hole 31 can be a through hole structure in the shape of a circle, a polygon or a strip.
[0047] In a preferred embodiment, as shown in Figure 2 The first communication hole 21 has a hole size d1, and 1.2mm≤d1≤2.5mm. This prevents the internal tab combustion debris or sparks from spattering out of the battery cell when thermal runaway occurs, thereby improving the safety performance of the battery cell. If d1 is too small, it will affect the exhaust effect of the pressure relief member 40 and is not easy to be stamped into a shape. If d1 is too large, it will be difficult to meet the spatter prevention requirement. It should be noted that when the first communication hole 21 is formed in a non-circular hole structure, as long as the maximum hole size of the first communication hole 21 is not more than 2.5mm and the minimum hole size is not less than 1.2mm, it is acceptable.
[0048] In a preferred embodiment, as shown in Figure 2 The second communication hole 31 has a hole size d2, and 2.5mm≤d2≤4mm. If d2 affects the exhaust effect, if d2 is too large, it will affect the insulation performance of the insulation member 30, thereby increasing the risk of poor insulation. It should be noted that when the second communication hole 31 is formed in a non-circular hole structure, as long as the maximum hole size of the second communication hole 31 is not more than 4mm and the minimum hole size is not less than 2.5mm, it is acceptable.
[0049] In a preferred embodiment, the first communication hole 21 is provided in a plurality, and the plurality of first communication holes 21 are arranged in an array on the support member 20; and / or the second communication hole 31 is provided in a plurality, and the plurality of second communication holes 31 are arranged in an array on the insulation member 30, thereby ensuring that the gas is smoothly discharged. The array arrangement mode of the plurality of first communication holes 21 or the plurality of second communication holes 31 can be a rectangular, circular or the same as the shape of the exhaust hole 11.
[0050] In the present embodiment, as shown in Figures 1 to 3 The plurality of bosses 12 are arranged at intervals around the circumference of the exhaust hole 11. In this way, the installation stability of the support member 20 can be improved, so that the support member 20 can effectively block the pole group when the battery cell fails, thereby limiting the displacement of the pole group.
[0051] The support member 20 is a metal member, for example, the material can be aluminum. The connection mode of the support member 20 and the boss 12 is preferably welding connection, so as to ensure reliable connection.
[0052] In the present embodiment, along the thickness direction of the cover plate body 10, the total area of the projection of the boss 12 on the cover plate body 10 is 400mm 2 to 900mm 2 In this way, the support member 20 and the boss 12 are connected firmly, and the situation that the support member 20 is extruded by the pole group and falls off from the boss 12 is avoided. When the number of the boss 12 is one, the projection area of the boss 12 on the cover plate body 10 is 400mm 2 to 900mm 2When multiple bosses 12 are provided, the total area of the projection of all bosses 12 onto the cover plate body 10 is 400 mm². 2 Up to 900mm 2 .
[0053] In this embodiment, as Figure 2 As shown, the height of the boss 12 in the thickness direction of the cover plate body 10 is H1, 1mm≤H1≤2mm. This makes the distance between the two opposing surfaces of the support member 20 and the cover plate body 10 1mm~2mm, thereby saving the space occupied inside the cell and effectively solving the problem of the exhaust hole 11 being blocked or blocked by the components inside the cell. At the same time, it allows gas to flow from the channel formed by the support member 20, the cover plate body 10 and the boss 12 to the exhaust hole 11, ensuring smooth exhaust.
[0054] In this embodiment, as Figure 2 As shown, the support member 20 is formed as a plate-like structure parallel to the cover plate body 10, thus reducing the space occupied by the support member 20 inside the cell. In a preferred embodiment, the thickness of the support member 20 is H2, 0.8mm≤H2≤1.5mm, to ensure that the support member 20 has sufficient cavity to block the electrode group and will not deform itself. At the same time, it can also reduce the space occupied by the support member 20 inside the cell, thereby increasing the cell capacity.
[0055] Furthermore, in this embodiment, such as Figure 2 As shown, the cell cover also includes a protective element 50, which is disposed on the side of the cover body 10 facing the outside of the cell to protect the pressure relief element 40, reduce the impact or damage to the pressure relief element 40, and prevent the pressure relief element 40 from opening prematurely, leading to cell failure. The protective element 50 can be an explosion-proof valve diaphragm. In this embodiment, the vent hole 11 of the portion covered by the protective element 50 allows communication between the outside of the cell and the pressure relief element 40 for detection, such as helium detection.
[0056] According to the present invention, a battery cell cover plate has an exhaust hole on its main body and a protrusion facing inward toward the battery cell. A support member is disposed on the surface of the protrusion away from the main body of the cover plate, such that the support member is spaced apart from the main body of the cover plate. Even if the electrode assembly shifts inside the battery cell, the support member can still block the electrode assembly, preventing the electrode assembly from blocking or even completely sealing the exhaust hole, thus ensuring smooth exhaust in the event of thermal runaway. In addition, the support member has a first connecting hole and the insulating member has a second connecting hole, thus ensuring smooth exhaust and providing protection.
[0057] The utility model provides a kind of electric core, including electric core cover plate as described above, avoid exhaust hole to be blocked or plugging by pole group when thermal runaway, guarantee smooth exhaust, improve the safety performance of electric core.
[0058] Finally, it should be noted that: the above-described embodiments, only for the specific embodiments of the present application, to illustrate the technical solutions of the present application, rather than limit it, the protection scope of the present application is not limited to this, although the present application is described in detail with reference to the foregoing examples, those skilled in the art should understand: any familiar with the technical field of the technical person within the technical range disclosed in the present application, it still can be modified or easily thought of change to the technical solution recorded in the foregoing examples, or equivalent replacement to part of technical features;And these modifications, changes or replacement, do not make the corresponding technical solution of the spirit of the present application deviate from the technical solutions of the present application, all should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be the protection scope of claim.
Claims
1. An electrode cover plate, characterized by, The electric cell cover plate comprises: a cover plate body provided with an exhaust hole, wherein a boss protruding towards the inside of the electric cell is formed on the cover plate body; a pressure relief member installed on the exhaust hole; a support member arranged on the surface of the boss away from the cover plate body, so that the support member is arranged in a spaced manner with the cover plate body, and a first communication hole is formed on the support member; an insulating member arranged on the side of the cover plate body facing the inside of the electric cell, wherein the support member is clamped between the cover plate body and the insulating member, and a second communication hole is formed on the insulating member.
2. The cell cover plate of claim 1, wherein, A plurality of bosses are arranged around the circumference of the exhaust hole.
3. The cell cover plate according to claim 1 or 2, characterized in that, The total area of the projection of the boss on the cover plate body is 400mm 2 up to 900mm 2 .
4. The cell cover plate of claim 1, wherein, The aperture size of the first communication hole is d1, and 1.2mm≤d1≤2.5mm.
5. The cell cover plate of claim 1, wherein, The aperture size of the second communication hole is d2, and 2.5mm≤d2≤4mm.
6. The cell cover plate of claim 1, wherein, The height size of the boss in the thickness direction of the cover plate body is H1, and 1mm≤H1≤2mm.
7. The cell cover plate of claim 1, wherein, The cover plate body is formed in a plate structure, and the support member is formed in a plate structure arranged in parallel to the cover plate body. The thickness size of the support member is H2, and 0.8mm≤H2≤1.5mm.
8. The cell cover plate of claim 1, wherein, A plurality of first communication holes are arranged in an array on the support member. And / or, a plurality of second communication holes are arranged in an array on the insulating member.
9. The cell cover plate of claim 1, wherein, Further comprising: a protection member arranged on the side of the cover plate body facing the outside of the electric cell, wherein the protection member covers part of the exhaust hole.
10. An electric cell characterized by The electric cell cover plate comprises the electric cell cover plate according to any one of claims 1 to 9.