Cover plate assembly, battery and battery pack

Abstract

The utility model relates to battery technical field discloses the cover plate subassembly, battery and battery package, include: cover plate body, set up the pole hole that penetrates along its thickness direction, cover plate body has the first surface and the second surface that are opposite along the thickness direction, pole structure, wear in the pole hole, lower insulating part, with the first surface is pasted and sets up, connecting piece, with pole structure welding, connecting piece sets up in the one side of lower insulating part away from cover plate body along the thickness direction and is set apart with lower insulating part, heat insulating part, at least partial setting between connecting piece and lower insulating part, the utility model makes lower insulating part and connecting piece set apart, and sets up heat insulating part between lower insulating part and connecting piece, can isolate the heat that connecting piece and the tab welding produce, avoid the melting of lower insulating part under the action of high temperature, guarantee the insulating effect between cover plate body and connecting piece, avoid the occurrence of short circuit problem, guarantee the safety performance of battery.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to cover plate assembly, battery and battery pack. Background Technology

[0002] To achieve current transfer between the battery cell and the cover plate assembly, the battery cell's tabs and the cover plate assembly's connecting tabs are typically welded together. As market demands for battery current transfer capacity and capacity increase, the thickness of the tabs and connecting tabs is also increasing. Therefore, the welding of the tabs and connecting tabs generates significant heat, posing a risk of melting adjacent components such as the lower plastic parts, thus affecting the safety performance of the cover plate assembly. Utility Model Content

[0003] This invention provides a cover plate assembly, a battery, and a battery pack to solve the problem in the prior art where components such as the lower plastic adjacent to the connecting piece have the risk of melting, affecting the safety performance of the cover plate assembly.

[0004] In a first aspect, this utility model provides a cover plate assembly, comprising: The cover plate body has a pole hole that extends through it along its thickness direction, and the cover plate body has a first surface and a second surface that are arranged opposite to each other along the thickness direction. A pole post structure is inserted through the pole post hole; The lower insulating component is fitted and disposed against the first surface; A connecting piece is welded to the pole structure. The connecting piece is disposed along the thickness direction on the side of the lower insulating member away from the cover plate body and is spaced apart from the lower insulating member. A heat insulation element is at least partially disposed between the connecting piece and the lower insulation element.

[0005] Beneficial effects: By spacing the lower insulator and connecting piece apart and placing a heat insulation component between them, the heat generated during the welding of the connecting piece and the tab can be isolated, preventing the lower insulator from melting under high temperature, ensuring the insulation effect between the cover plate body and the connecting piece, avoiding short circuit problems, and ensuring the safety performance of the battery.

[0006] In one alternative embodiment, the side of the connecting piece facing the lower insulator is recessed along the thickness direction to form a groove, and a portion of the heat insulation member extends into the groove.

[0007] Beneficial effects: The grooved part is used to position and limit the heat insulation component, ensuring the accuracy and stability of the heat insulation component's position.

[0008] In one alternative embodiment, the connecting piece extends toward the groove wall of the groove portion to form a blocking portion, and the heat insulation member has a portion located along the thickness direction on the side of the blocking portion away from the lower insulation member and abutting against the blocking portion.

[0009] Beneficial effect: By setting the blocking part, the heat insulation component is prevented from falling out of the groove, ensuring the reliability of the connection between the heat insulation component and the connecting piece.

[0010] In one optional embodiment, the lower insulating member has a fixing hole that extends at least along the thickness direction through the side of the lower insulating member facing the connecting piece. One end of the heat insulation member is inserted into the fixing hole and is interference-fitted with the fixing hole, while the other end of the heat insulation member extends out of the fixing hole and abuts against the connecting piece.

[0011] Beneficial effect: By using the interference fit between the heat insulation component and the fixing hole, the heat insulation component is installed on the lower insulation component, ensuring the reliability of the connection between the heat insulation component and the lower insulation component.

[0012] In one optional embodiment, the interference fit between the heat insulation element and the fixing hole is a, satisfying 0 < a ≤ 0.5 mm.

[0013] Beneficial effects: While ensuring the reliability of the connection between the heat insulation component and the lower insulation component, it facilitates the assembly of the heat insulation component and the fixing hole.

[0014] In one optional embodiment, the lower insulating member has a fixing hole that extends at least along the thickness direction through the side of the lower insulating member facing the connecting piece. One end of the heat insulation member is inserted into the fixing hole and engages with the lower insulating member, while the other end of the heat insulation member extends out of the fixing hole and abuts against the connecting piece.

[0015] Beneficial effect: By using a snap-fit ​​connection between the heat insulation component and the lower insulation component, the heat insulation component is installed on the lower insulation component, ensuring the reliability of the connection between the heat insulation component and the lower insulation component.

[0016] In one optional embodiment, the spacing between the connecting piece and the lower insulating member along the thickness direction is K, satisfying 0 < K ≤ 0.3 mm; and / or, Along the thickness direction, the thickness of the heat insulation element is T, which satisfies 0.7 < T ≤ 1 mm.

[0017] Beneficial effects: While ensuring the heat insulation effect between the connecting piece and the lower insulator, it avoids affecting the volumetric energy density and gravimetric energy density of the battery; While ensuring the thermal insulation effect between the connecting piece and the lower insulator and the reliability of the connection between the thermal insulation and the connecting piece and / or the lower insulator, it is necessary to avoid affecting the volumetric energy density and gravimetric energy density of the battery.

[0018] In one optional embodiment, the first end of the pole structure extends out of the pole hole, the connecting piece has a mounting hole that extends through the thickness direction, and the first end is inserted into the mounting hole and welded to the connecting piece.

[0019] Beneficial effects: By partially overlapping the connecting pieces and electrode structures in the thickness direction, the overall thickness of the cover plate assembly can be reduced, leaving more space for the battery cells and improving the volumetric energy density of the battery.

[0020] Secondly, this utility model also provides a battery, comprising: The housing has an opening at at least one end; The aforementioned cover assembly is connected to the housing and seals the opening, and the housing and the cover assembly together form an accommodating space; A battery cell is disposed in the receiving space, the battery cell including a tab, the tab being welded to the connecting piece.

[0021] Thirdly, this utility model also provides a battery pack, including the aforementioned battery. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a partial cross-sectional view of a cover plate assembly in the thickness direction according to an embodiment of the present utility model. Figure 2 This is a schematic diagram of the structure of the lower insulating member, connecting piece, and heat insulation member according to a first embodiment of the present utility model; Figure 3 This is a schematic diagram of the structure of the lower insulating member, connecting piece, and heat insulation member according to a second embodiment of the present utility model; Figure 4 This is a schematic diagram of the third embodiment of the lower insulating member, connecting piece, and heat insulation member of this utility model.

[0024] Explanation of reference numerals in the attached figures: 1. Cover plate body; 11. First surface; 12. Second surface; 2. Pole post structure; 3. Lower insulating component; 31. Fixing hole; 32. Locking block; 4. Connecting piece; 41. Groove part; 42. Blocking part; 5. Heat insulation component; 51. Slot; 6. Sealing component. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0026] The following is combined with Figures 1 to 4 The following describes embodiments of the present invention.

[0027] According to an embodiment of the present invention, a cover plate assembly is provided, comprising: a cover plate body 1 having an electrode post hole that extends through it along its thickness direction; the cover plate body 1 having a first surface 11 and a second surface 12 that are disposed opposite each other along its thickness direction; an electrode post structure 2 passing through the electrode post hole; a lower insulating member 3 being fitted to the first surface 11; a connecting piece 4 being welded to the electrode post structure 2; the connecting piece 4 being disposed along its thickness direction on the side of the lower insulating member 3 away from the cover plate body 1 and spaced apart from the lower insulating member 3; and a heat insulation member 5 being at least partially disposed between the connecting piece 4 and the lower insulating member 3.

[0028] The cover plate assembly of this embodiment is used to space the lower insulating member 3 and the connecting piece 4, and a heat insulation member 5 is provided between the lower insulating member 3 and the connecting piece 4. This can isolate the heat generated by welding the connecting piece 4 and the electrode tab, prevent the lower insulating member 3 from melting under high temperature, ensure the insulation effect between the cover plate body 1 and the connecting piece 4, avoid short circuit problems, and ensure the safety performance of the battery.

[0029] It is worth noting that in related technologies, the connecting piece 4 typically has a high melting temperature and good thermal conductivity. Especially for the negative electrode, the connecting piece 4 is made of copper, with a melting temperature of 1083.4℃ and a thermal conductivity of 386 W / (m·K). In the cover plate assembly of related technologies, the connecting piece 4 and the lower insulating component 3 are fitted together, and the lower insulating component 3 is generally made of PP (polypropylene), with a melting temperature of around 120℃. Under the influence of the welding heat between the connecting piece 4 and the electrode tab, the lower insulating component 3 is prone to melting, causing the connecting piece 4 to contact the cover plate body 1 and triggering a short circuit.

[0030] In this embodiment, by providing a heat insulation component 5 between the connecting piece 4 and the lower insulating component 3, the heat transferred from the connecting piece 4 to the lower insulating component 3 is isolated, preventing the lower insulating component 3 from overheating and melting, thus ensuring the reliability of the lower insulating component 3 and thereby ensuring the safety of the battery.

[0031] It should be noted that, in one embodiment, the heat insulation member 5 is connected to the connecting piece 4 and / or the lower insulating member 3. That is, the heat insulation member 5 can be connected only to the connecting piece 4, only to the lower insulating member 3, or both. The following describes various implementation methods for connecting the heat insulation member 5 to the connecting piece 4 and connecting the heat insulation member 5 to the lower insulating member 3.

[0032] In the first implementation, such as Figure 2 As shown, the side of the connecting piece 4 facing the lower insulating member 3 is recessed along the thickness direction to form a groove 41, and a portion of the heat insulation member 5 extends into the groove 41. This arrangement uses the groove 41 to position and limit the heat insulation member 5, ensuring the accuracy and stability of its position.

[0033] Furthermore, in the first embodiment, such as Figure 2 As shown, the connecting piece 4 extends into the groove of the groove 41 and forms a blocking portion 42. The heat insulation member 5 has a portion located along its thickness direction on the side of the blocking portion 42 away from the lower insulating member 3 and is disposed in abutment against the blocking portion 42. By providing the blocking portion 42, the heat insulation member 5 is prevented from coming out of the groove 41, ensuring the reliability of the connection between the heat insulation member 5 and the connecting piece 4.

[0034] It is worth noting that by performing two blind hole punchings on the side of the connecting piece 4 facing the lower insulating member 3, a groove portion 41 with a blocking portion 42 can be formed. Specifically, the first punching creates a blind hole with a smaller diameter and a larger depth. The second punching is concentric with the first punching and has a larger diameter and a smaller depth. Therefore, during the second punching, some material can be pressed down, and the blocking portion 42 can be formed at the junction of the first and second punchings.

[0035] It should be noted that the processing method of the heat insulation component 5 in the first embodiment can be as follows: first, install the lower insulating component 3 and the connecting piece 4 into place so that a predetermined gap is formed between the lower insulating component 3 and the connecting piece 4, and then fill the heat insulation material between the lower insulating component 3 and the connecting piece 4, and fill the heat insulation material into the groove portion 41, thereby forming the inlay structure of the heat insulation component 5 and the connecting piece 4.

[0036] Furthermore, in the first embodiment, such as Figure 2 As shown, the side of the connecting piece 4 facing the lower insulating member 3 is provided with a plurality of grooves 41 spaced apart.

[0037] In the second implementation, such as Figure 3 As shown, the lower insulating member 3 has a fixing hole 31, which extends at least along the thickness direction through the side of the lower insulating member 3 facing the connecting piece 4. One end of the heat insulation member 5 is inserted into the fixing hole 31 and is interference-fitted with the fixing hole 31. The other end of the heat insulation member 5 extends out of the fixing hole 31 and abuts against the connecting piece 4. Through the interference fit between the heat insulation member 5 and the fixing hole 31, the heat insulation member 5 is installed on the lower insulating member 3, ensuring the reliability of the connection between the heat insulation member 5 and the lower insulating member 3.

[0038] It is worth noting that the fixing hole 31 can be a blind hole that only penetrates the side of the lower insulating member 3 facing the connecting piece 4, or it can be a through hole that penetrates both opposite sides of the lower insulating member 3 along the thickness direction.

[0039] It should be noted that in the second embodiment, the heat insulation component 5 is columnar, sheet-like, or block-like, and is embedded in the fixing hole 31 by interference fit.

[0040] It is understandable that in the second implementation, such as Figure 3 As shown, although the heat insulation component 5 does not completely fill the gap between the connecting piece 4 and the lower insulation component 3, the air in the unfilled space can still play a certain role in heat insulation.

[0041] Furthermore, in the second embodiment, such as Figure 3 As shown, the interference fit between the heat insulation component 5 and the fixing hole 31 is 'a', satisfying 0 < a ≤ 0.5 mm. This arrangement ensures the reliability of the connection between the heat insulation component 5 and the lower insulation component 3 while facilitating the assembly of the heat insulation component 5 and the fixing hole 31.

[0042] It is worth noting that in the second embodiment, the outer diameter of the heat insulation component 5 is D1, and the inner diameter of the fixing hole 31 is D2, therefore a = D1 - D2.

[0043] Optionally, the value of 'a' can be any value among 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, and 0.5mm, or a value between any two values.

[0044] Furthermore, in the second embodiment, such as Figure 3 As shown, the lower insulating member 3 is provided with a number of fixing holes 31 spaced apart.

[0045] In the third implementation, such as Figure 4As shown, the lower insulating member 3 has a fixing hole 31, which extends at least along the thickness direction through the side of the lower insulating member 3 facing the connecting piece 4. One end of the heat insulation member 5 is inserted into the fixing hole 31 and engages with the lower insulating member 3, while the other end of the heat insulation member 5 extends out of the fixing hole 31 and abuts against the connecting piece 4. By engaging with the lower insulating member 3, the heat insulation member 5 is installed on the lower insulating member 3, ensuring the reliability of the connection between the heat insulation member 5 and the lower insulating member 3.

[0046] It is worth noting that the fixing hole 31 can be a blind hole that only penetrates the side of the lower insulating member 3 facing the connecting piece 4, or it can be a through hole that penetrates both opposite sides of the lower insulating member 3 along the thickness direction.

[0047] Specifically, in the third implementation, such as Figure 4 As shown, the lower insulating member 3 has a protruding locking block 32 on the wall of the fixing hole 31, and the peripheral wall of the heat insulation member 5 has a recessed locking groove 51. The locking block 32 is inserted into the locking groove 51 to form a locking engagement; and / or, the lower insulating member 3 can also have a recessed locking groove on the wall of the fixing hole 31, and the peripheral wall of the heat insulation member 5 can protrude to form a locking block, and the locking block can be inserted into the locking groove to form a locking engagement.

[0048] It is understandable that in the third implementation, such as Figure 4 As shown, although the heat insulation component 5 does not completely fill the gap between the connecting piece 4 and the lower insulation component 3, the air in the unfilled space can still play a certain role in heat insulation.

[0049] Furthermore, in the third embodiment, such as Figure 4 As shown, the lower insulating member 3 is provided with a number of fixing holes 31 spaced apart.

[0050] In one embodiment, such as Figures 2 to 4 As shown, the distance between the connecting piece 4 and the lower insulating member 3 along the thickness direction is K, which satisfies 0 < K ≤ 0.3 mm. This setting ensures the heat insulation effect between the connecting piece 4 and the lower insulating member 3 while avoiding any impact on the volumetric energy density and gravimetric energy density of the battery.

[0051] It is worth noting that if the value of K is too large, the space occupied by the heat insulation component 5 along the thickness direction will be too large, which will result in the overall thickness of the cover assembly being too large, squeezing the space for the battery cell installation and affecting the volumetric energy density of the battery. In addition, it will lead to an increase in the weight of the cover assembly, affecting the weight energy density of the battery.

[0052] Optionally, K can be any value from 0.05mm, 0.08mm, 0.1mm, 0.12mm, 0.15mm, 0.18mm, 0.2mm, 0.22mm, 0.25mm, 0.28mm, 0.3mm, or a value between any two values.

[0053] In one embodiment, such as Figures 2 to 4 As shown, the thickness of the heat insulation component 5 is T along the thickness direction, satisfying 0.7 < T ≤ 1 mm. This setting ensures the heat insulation effect between the connecting piece 4 and the lower insulating component 3, as well as the reliability of the connection between the heat insulation component 5 and the connecting piece 4 and / or the lower insulating component 3, while avoiding any impact on the volumetric energy density and gravimetric energy density of the battery.

[0054] It is worth noting that if the value of T is too small, the distance between the connecting piece 4 and the lower insulating component 3 may be too close, affecting the heat insulation effect. It may also lead to insufficient connection strength between the heat insulation component 5 and the connecting piece 4 and / or between the heat insulation component 5 and the lower insulating component 3, affecting the stability and reliability of the heat insulation component 5. If the value of T is too large, the space occupied by the heat insulation component 5 along the thickness direction will be too large, resulting in an excessively large overall thickness of the cover assembly, which will compress the space for the battery cell and affect the volumetric energy density of the battery. In addition, it will increase the weight of the cover assembly, affecting the gravimetric energy density of the battery.

[0055] Optionally, T can be any value from 0.71mm, 0.73mm, 0.75mm, 0.78mm, 0.8mm, 0.82mm, 0.85mm, 0.88mm, 0.9mm, 0.92mm, 0.95mm, 0.98mm, 1mm, or a value between any two of these values.

[0056] It is worth noting that, such as Figures 2 to 4 As shown, dimension T refers to the total thickness of the heat insulation component 5 along the thickness direction, including both the portion embedded in the connecting piece 4 and the lower insulation component 3, and the portion located between the connecting piece 4 and the lower insulation component 3.

[0057] In one embodiment, such as Figure 1 As shown, the first end of the electrode post structure 2 extends out to form an electrode post hole, and the connecting piece 4 has a mounting hole that extends through the thickness direction. The first end of the connecting piece 4 is inserted into the mounting hole and welded to the connecting piece 4. This arrangement, which partially overlaps the connecting piece 4 and the electrode post structure 2 in the thickness direction, can reduce the overall thickness of the cover plate assembly, leaving more space for the battery cell and improving the volumetric energy density of the battery.

[0058] In one embodiment, such as Figure 1 As shown, a sealing element 6 is arranged around the outer periphery of the pole post structure 2, and the sealing element 6 is pressed between the cover plate body 1 and the connecting piece 4. By providing the heat insulation element 5, not only can the lower insulating element 3 be prevented from melting, but also the sealing element 6 can be prevented from melting, thus ensuring the sealing performance of the cover plate assembly.

[0059] In one embodiment, the heat insulation component 5 has a high temperature resistance of not less than 1100°C.

[0060] In one embodiment, the thermal conductivity of the insulation element 5 is not higher than 0.12 W / (m·K).

[0061] In one embodiment, the compressive yield strength of the thermal insulation element 5 is not less than 50 MPa.

[0062] In one embodiment, the heat insulation element 5 has electrolyte resistance properties.

[0063] In one embodiment, the heat insulation element 5 is made of insulating material.

[0064] In one embodiment, the heat insulation component 5 is made of ceramic material or nano-insulation material, etc.

[0065] According to an embodiment of the present invention, another aspect provides a battery comprising: The housing has an opening at at least one end; The aforementioned cover assembly is connected to the housing and seals the opening; the housing and the cover assembly together form an accommodating space. The battery cell is housed in the housing space. The battery cell includes a tab, which is welded to the connecting piece 4.

[0066] According to an embodiment of the present invention, in another aspect, a battery pack is also provided, including the battery described above.

[0067] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cover plate assembly, characterized in that, include: The cover plate body (1) has a pole hole that runs through it along its thickness direction. The cover plate body (1) has a first surface (11) and a second surface (12) that are arranged opposite to each other along the thickness direction. The pole post structure (2) is inserted through the pole post hole; The lower insulating member (3) is attached to the first surface (11); The connecting piece (4) is welded to the pole structure (2). The connecting piece (4) is disposed along the thickness direction on the side of the lower insulating member (3) away from the cover plate body (1) and spaced apart from the lower insulating member (3). The heat insulation element (5) is at least partially disposed between the connecting piece (4) and the lower insulation element (3).

2. The cover plate assembly according to claim 1, characterized in that, The connecting piece (4) has a recessed groove (41) on the side facing the lower insulating member (3) along the thickness direction, and a portion of the heat insulation member (5) extends into the groove (41).

3. The cover plate assembly according to claim 2, characterized in that, The connecting piece (4) extends toward the groove wall of the groove (41) to form a blocking part (42), and the heat insulation member (5) has a portion located along the thickness direction on the side of the blocking part (42) away from the lower insulation member (3) and abuts against the blocking part (42).

4. The cover plate assembly according to claim 1, characterized in that, The lower insulating member (3) has a fixing hole (31) which penetrates at least along the thickness direction on the side of the lower insulating member (3) facing the connecting piece (4). One end of the heat insulation member (5) is inserted into the fixing hole (31) and is press-fitted with the fixing hole (31). The other end of the heat insulation member (5) extends out of the fixing hole (31) and abuts against the connecting piece (4).

5. The cover plate assembly according to claim 4, characterized in that, The interference fit between the heat insulation component (5) and the fixing hole (31) is a, which satisfies 0 < a ≤ 0.5 mm.

6. The cover plate assembly according to claim 1, characterized in that, The lower insulating member (3) has a fixing hole (31) that extends through at least one side of the lower insulating member (3) facing the connecting piece (4) along the thickness direction. One end of the heat insulation member (5) is inserted into the fixing hole (31) and engages with the lower insulating member (3). The other end of the heat insulation member (5) extends out of the fixing hole (31) and abuts against the connecting piece (4).

7. The cover plate assembly according to any one of claims 1 to 6, characterized in that, Along the thickness direction, the distance between the connecting piece (4) and the lower insulating member (3) is K, satisfying 0 < K ≤ 0.3 mm; and / or, Along the thickness direction, the thickness of the heat insulation element (5) is T, which satisfies 0.7 < T ≤ 1 mm.

8. The cover plate assembly according to any one of claims 1 to 6, characterized in that, The first end of the pole structure (2) extends out of the pole hole, and the connecting piece (4) has a mounting hole that runs through the thickness direction. The first end is inserted into the mounting hole and welded to the connecting piece (4).

9. A battery, characterized in that, include: The housing has an opening at at least one end; The cover plate assembly according to any one of claims 1 to 8 is connected to the housing and seals the opening, wherein the housing and the cover plate assembly enclose a receiving space; A battery cell is disposed in the receiving space, the battery cell including a tab, the tab being welded to the connecting piece (4).

10. A battery pack, characterized in that, Includes the battery as described in claim 9.

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