Battery cover plate assembly and battery

Abstract

A battery cover plate assembly and a battery. The battery cover plate assembly comprises a cover plate body (100), a first plastic component (200), a second plastic component (300), and a terminal post. The first plastic component (200) and the second plastic component (300) are respectively disposed on two sides of the cover plate body (100). The terminal post is disposed on the side of the first plastic component (200) facing away from the cover plate body (100). A tab of an electrode assembly passes through the second plastic component (300), the cover plate body (100), and the first plastic component (200), and is then connected to the terminal post.

Description

Battery cover assembly and battery

[0001] This application claims priority to Chinese Patent Application No. 202411589670.1, filed with the Chinese Patent Office on November 8, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery technology, such as a battery cover assembly and a battery. Background Technology

[0003] In lithium-ion batteries, the battery cover assembly is a key component. It connects to the housing to encapsulate the electrode assembly within the housing, while the terminals on the battery cover assembly allow the electrode tabs to be brought out, serving to connect to external circuits.

[0004] Battery cover assemblies in related technologies generally include a riveting block, an upper plastic part, a terminal post, a cover body, a lower plastic part, and a sealing ring. The sealing ring is fitted over the terminal post. The post's cylindrical portion passes sequentially through the lower plastic part, the cover body, and the upper plastic part from one side of the cover body and connects to the riveting block. The plate-shaped portion of the terminal post is pressed against the lower plastic part. After the battery cover assembly is installed with the housing, the plate-shaped portion of the terminal post and the lower plastic part are located inside the housing and sandwiched between the cover body and the electrode assembly. Because the plate-shaped portion of the terminal post and the lower plastic part have a certain height, they occupy the internal space of the housing, reducing the space for the electrode assembly and hindering efficient space utilization, resulting in low battery energy density. Furthermore, when the tabs are led out from the electrode assembly and connected to the plate-shaped portion of the terminal post, they need to be bent in a C-shape or S-shape. Due to the lack of support, the shape of the tabs within the housing may deform, posing a short-circuit risk between the tabs and the housing. Summary of the Invention

[0005] This application provides a battery cover assembly and a battery, in which the terminals are arranged outside the housing, eliminating the need to occupy the internal space of the housing. This increases the volume of the electrode assembly, resulting in high space utilization and a high energy density for the battery. Furthermore, the electrode tabs have a good shape, making it less likely for them to overlap and short-circuit with the housing, thus ensuring high battery safety.

[0006] The following technical solution is adopted in this application:

[0007] On one hand, this application provides a battery cover assembly, including:

[0008] The cover plate body is provided with a first mounting hole;

[0009] A first plastic part is disposed on one side of the cover plate body. The first plastic part includes a first plastic part body and a first through hole is provided on the first plastic part body.

[0010] The second plastic part is disposed on the other side of the cover plate body. The second plastic part includes a second plastic part body, on which a second through hole and an electrode ear shaping structure are provided. The electrode ear shaping structure is disposed in the circumferential direction of the second through hole, and the electrode ear shaping structure is located on the side of the second plastic part body away from the cover plate body.

[0011] The electrode post is located on the side of the first plastic part away from the cover plate body. The electrode lug of the electrode group passes through the second through hole, the first mounting hole, and the first through hole and is connected to the electrode post.

[0012] Optionally, the electrode tab shaping structure includes two guide plates, which are respectively disposed on both sides of the second through hole along the first direction, and the two guide plates are inclined in a direction away from the axis of the second through hole. Along the direction away from the second through hole, a flared mouth with a gradually widening opening is formed between the two guide plates. The larger end of the flared mouth faces the electrode assembly, and the smaller end of the flared mouth is connected to the second plastic body. The electrode tab is inserted into the flared mouth.

[0013] Wherein, the included angle between the guide plate and the axis of the second through hole is , The range of values ​​is .

[0014] Optionally, along the first direction, the first through holes on the first plastic body are provided in multiple intervals, and the second through holes and the tab shaping structure on the second plastic body are provided in multiple intervals, and the first through holes, the second through holes and the tab shaping structure correspond one-to-one.

[0015] Optionally, the second plastic part body is provided with a support structure on the side near the cover plate body. The support structure includes a connecting plate and a support plate. The connecting plate is connected to the tab shaping structure. The support plate is disposed on the end face of the connecting plate near the cover plate body and abuts against the cover plate body.

[0016] Optionally, along the first direction, the distance between the support plate and the tab shaping structure is e, and the value of e ranges from... ;

[0017] And / or, along the second direction, the distance between the end face of the connecting plate opposite to the cover plate body and the end face of the second plastic part body opposite to the cover plate body is f, where f takes values ​​ranging from... .

[0018] Optionally, the first through hole is provided with a first flange in the circumferential direction, the first flange extending into the first mounting hole, and the second through hole is provided with a second flange in the circumferential direction, the second flange extending into the first mounting hole and connecting with the first flange, and one of the first flange and the second flange is in contact with the inner wall of the first mounting hole.

[0019] Optionally, the second flange is sleeved outside the first flange, and the peripheral sidewall of the second flange fits against the inner wall of the first mounting hole;

[0020] Alternatively, the first flange is sleeved outside the second flange, and the peripheral sidewall of the first flange fits against the inner wall of the first mounting hole;

[0021] Alternatively, a first insertion groove is provided on the end face of the first flange facing the second plastic part, the second flange extends into the first insertion groove, and the peripheral sidewall of the first flange fits against the inner wall of the first mounting hole.

[0022] Alternatively, a second insertion groove is provided on the end face of the second flange facing the first plastic part, the first flange extends into the second insertion groove, and the peripheral sidewall of the second flange fits against the inner wall of the first mounting hole.

[0023] Optionally, a groove is provided on the end face of the cover plate body opposite to the second plastic part, and an overlapping part is provided in the circumferential direction of the first plastic part body. The overlapping part is embedded in the groove and fits against the bottom wall of the groove.

[0024] Wherein, along the second direction, the thickness of the cover plate body is H, and the distance between the end face of the overlapping portion facing away from the second plastic part and the end face of the cover plate body facing away from the second plastic part is b, and the value range of b satisfies: ;

[0025] And / or, along the first direction, the width of the overlap is c, and the range of values ​​for c satisfies: .

[0026] Optionally, the first plastic part and the cover plate body are heat-fused together, and the second plastic part and the cover plate body are heat-fused together.

[0027] On the other hand, this application provides a battery including a housing, an electrode assembly, and a battery cover assembly as described in any of the above embodiments, wherein the battery cover assembly is encapsulated at the opening of the housing, and the electrode assembly is disposed within the housing.

[0028] The technical effects of this application are as follows:

[0029] This application provides a battery cover assembly, including a cover body, a first plastic part, a second plastic part, and a terminal post. The first and second plastic parts are respectively disposed on both sides of the cover body, and the terminal post is disposed on the side of the first plastic part facing away from the cover body. After the battery cover assembly is assembled, the electrode tabs of the electrode assembly pass through the second plastic part, the cover body, and the first plastic part and connect to the terminal post. Since the terminal post is disposed on the side of the first plastic part facing away from the cover body, the terminal post does not occupy the internal space of the casing, greatly saving the internal space of the casing. The volume of the electrode assembly is increased, and the internal space utilization of the casing is high, which helps to improve the energy density of the battery. The second plastic part is provided with a tab shaping structure, which can fold the tabs together, resulting in a good overall shape of the tabs. In addition, the tab shaping structure can also support the tabs, preventing short circuits between the tabs and the casing, and ensuring battery safety.

[0030] This application also provides a battery including the aforementioned battery cover assembly. By employing the aforementioned battery cover assembly, the terminals do not occupy the internal space of the casing, the volume of the electrode assembly is increased, and the energy density of the battery is high. Furthermore, the tab shaping structure on the second plastic part can retract the tabs, resulting in a good overall shape of the tabs. Short-circuit connections between the tabs and the casing are less likely to occur, thus ensuring good battery safety. Attached Figure Description

[0031] Figure 1 is an exploded view of the battery cover assembly provided in Embodiment 1 of this application;

[0032] Figure 2 is a top view of the battery cover assembly provided in Embodiment 1 of this application;

[0033] Figure 3 is a cross-sectional view of section AA in Figure 2;

[0034] Figure 4 is a magnified view of part B in Figure 3;

[0035] Figure 5 is an exploded view of the battery cover assembly provided in Embodiment 1 of this application from another perspective;

[0036] Figure 6 is a structural schematic diagram of the first plastic part provided in Embodiment 1 of this application;

[0037] Figure 7 is a cross-sectional view of the battery cover assembly provided in Embodiment 2 of this application;

[0038] Figure 8 is a magnified view of part C in Figure 7;

[0039] Figure 9 is a cross-sectional view of the battery cover assembly provided in Embodiment 3 of this application;

[0040] Figure 10 is a magnified view of part D in Figure 9;

[0041] Figure 11 is a cross-sectional view of the battery cover assembly provided in Embodiment 4 of this application;

[0042] Figure 12 is a magnified view of a portion of point E in Figure 11.

[0043] In the picture:

[0044] 100. Cover plate body; 110. First mounting hole; 120. Settling groove; 130. First fixing groove; 140. Second fixing groove; 150. Second mounting hole; 151. Support rib; 160. First injection hole;

[0045] 200, First plastic part; 210, First plastic part body; 211, First through hole; 220, First flange; 221, First insertion groove; 230, Overlap; 240, Connecting rib; 241, Mounting groove; 250, Third flange; 260, First weld pillar;

[0046] 300, Second plastic part; 310, Second plastic part body; 311, Second through hole; 312, Tab shaping structure; 3121, Guide plate; 3122, Flared mouth; 313, Support structure; 3131, Connecting plate; 3132, Support plate; 320, Second flange; 321, Second insertion groove; 330, Second weld pillar; 340, Vent hole;

[0047] 400. Explosion-proof valve. Detailed Implementation

[0048] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Specifically, the terms "first position" and "second position" refer to two different positions. Moreover, "above," "on top of," and "over" the first feature in relation to the second feature includes the first feature directly above and diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "under," and "below" the first feature in relation to the second feature includes the first feature directly below and diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0049] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0050] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0051] Example 1

[0052] As shown in Figures 1-4, this embodiment provides a battery cover assembly, which includes a cover body 100, a first plastic part 200, a second plastic part 300, and a terminal post. The first plastic part 200 is disposed on one side of the cover body 100, and the terminal post is disposed on the side of the first plastic part 200 opposite to the cover body 100. The second plastic part 300 is disposed on the opposite side of the cover body 100 opposite to the first plastic part 200. The cover body 100 is provided with a first mounting hole 110. The first plastic part 200 includes a first plastic part body 210, which has a first through hole 211. The second plastic part 300 includes a second plastic part body 310, which has a second through hole 311.

[0053] After the battery cover assembly is assembled, the electrode tabs of the electrode group pass through the second through hole 311, the first mounting hole 110, and the first through hole 211 and connect to the terminal post, thereby connecting the electrode group to the external circuit. The cover body 100 is connected to the battery casing. Compared with the previous solution where the terminal post is placed inside the casing, in this embodiment, the second plastic part 300 is located inside the casing, while the terminal post is placed outside the casing. Therefore, the terminal post does not occupy the internal space of the casing. The electrode tabs directly pass through the second plastic part 300, the cover body 100, and the first plastic part 200 and connect to the terminal post, which greatly saves the internal space of the casing. The volume of the electrode group is increased, and the internal space utilization of the casing is high, which helps to improve the energy density of the battery.

[0054] In one embodiment, the cover body 100 is formed by the housing, that is, no separate cover body is provided, and the first plastic part 200 and the second plastic part 300 are fixed to the housing.

[0055] In this embodiment, the second plastic body 310 is provided with a tab shaping structure 312. The tab shaping structure 312 is disposed circumferentially around the second through hole 311, and is located on the side of the second plastic body 310 away from the cover plate body 100, that is, on the side closer to the electrode assembly. The tab shaping structure 312 can retract the tab into the second through hole 311, and provides good guidance when the tab protrudes from the second through hole 311, resulting in a good overall shape of the tab. In addition, the tab shaping structure 312 can also support the tab, preventing short circuit between the tab and the casing, thus ensuring battery safety.

[0056] As an optional solution, the tab shaping structure 312 in this embodiment includes two guide plates 3121, which are respectively disposed on both sides of the second through hole 311 along the first direction (the Y-axis direction shown in Figures 1-3), and the two guide plates 3121 are inclined in a direction away from the axis of the second through hole 311. Along the direction away from the second through hole 311, a flared mouth 3122 is formed between the two guide plates 3121, with the larger end of the flared mouth 3122 facing the electrode assembly, and the smaller end of the flared mouth 3122 connected to the second plastic body 310 circumferentially connected to the second through hole 311. During installation, the tab is inserted into the second through hole 311 from the larger end of the flared mouth 3122. Along the direction close to the second through hole 311, the opening of the flared mouth 3122 gradually narrows. Therefore, when the electrode tab is inserted into the flared mouth 3122, the guide plates 3121 on both sides of the flared mouth 3122 can effectively gather the electrode tab into the second through hole 311. The electrode tab does not need to be bent in a C-shape or S-shape inside the housing, and the overall shape is good.

[0057] The included angle between the axis of the guide plate 3121 and the axis of the second through hole 311 is α, and the value of α is in the range of 45°≤α≤87°. For example, the value of α can be 45°, 50°, 60°, 70°, 80°, 87°, etc. By controlling the value of α within the above range, it can be ensured that the tab shaping structure 312 can well contain the tab within the second through hole 311. It should be noted that when the value of α is too large, it cannot play a good shaping role for the tab; when the value of α is too small, the tab is easy to be inserted backward into the electrode assembly, causing a short circuit, and will increase the height of the second plastic part 300 along the second direction (the second direction is the Z-axis direction shown in Figures 1 and 3), which is not conducive to improving the energy density of the battery.

[0058] This embodiment uses a housing with two electrode groups as an example. Each electrode group has a positive electrode tab and a negative electrode tab at both ends along its length. The positive electrode tabs of both electrode groups are located on the same side, and the negative electrode tabs of both electrode posts are also located on the same side. Two first plastic parts 200 and electrode posts are provided. The two first plastic parts 200 are respectively located at both ends of the cover plate body 100 along a third direction (the X-axis direction shown in Figures 1 and 2). The electrode posts on the side of the two first plastic parts 200 away from the cover plate body 100 are respectively the positive electrode post and the negative electrode post. Each first plastic part 200 has two first through holes 211 on its first plastic part body 210, which are spaced apart along a first direction (the Y-axis direction shown in Figures 1 and 2). The two first through holes 211 on the first plastic part 200 allow the positive electrode tabs of the two electrode groups to pass through, or allow the negative electrode tabs of the two electrode groups to pass through.

[0059] The second plastic part 300 is provided with two second through holes 311 at each end of the second plastic part body 310 along a third direction, that is, there are four second through holes 311 in total. Each second through hole 311 is provided with a tab shaping structure 312 around its circumference. The first through hole 211, the second through hole 311 and the tab shaping structure 312 correspond one-to-one. The positive tab of each electrode group passes through a tab shaping structure 312, a second through hole 311, a first mounting hole 110 and a first through hole 211 and then connects to the positive terminal. The negative tab of each electrode group passes through the tab shaping structure 312, the second through hole 311, the first mounting hole 110 and the first through hole 211 at the other end of the second plastic part 300 and then connects to the negative terminal. In this way, the tabs of the electrode group are led out from inside the housing and connected to the terminal on the outside of the housing, without occupying the internal space of the housing. The volume of the electrode group is increased, the space utilization rate is high, and the energy density of the battery is high. It should be noted that each tab is provided with a tab shaping structure 312 to ensure that each tab has a good shape and is not prone to short circuits due to overlap with the shell.

[0060] Optionally, in this embodiment, the second plastic part body 310 is further provided with a support structure 313 on the side near the cover plate body 100. Multiple support structures 313 are provided, with two support structures 313 respectively located at both ends of the second plastic part 300 along the first direction and connected to the tab shaping structure 312 on one side therewith. The remaining support structures 313 are arranged between two adjacent tab shaping structures 312 along the first direction. One or more support structures 313 may be provided between each pair of tab shaping structures 312. Here, we will use one support structure 313 between each pair of tab shaping structures 312 as an example. That is, each tab shaping structure 312 is supported on both sides along the first direction. The multiple support structures 313 described above can provide good support for the tab shaping structure 312, ensuring high mechanical strength and preventing deformation.

[0061] In some embodiments, the support structure 313 includes a connecting plate 3131 and a support plate 3132. One end of the connecting plate 3131, located near the end of the second plastic body 310 along the first direction, is connected to the tab shaping structure 312. The other end of the connecting plate 3131, located near the end of the second plastic body 310 along the first direction, is connected to the support plate 3132. The support plate 3132 is connected to the edge of the connecting plate 3131 near the edge of the second plastic body 310 along the first direction. The support plate 3132 is disposed on the end face of the connecting plate 3131 near the cover plate body 100. The support plate 3132 abuts against the cover plate body 100, thereby providing support for the tab shaping structure 312 connected thereto. In the support structure 313 located between two adjacent tab shaping structures 312, the two ends of the connecting plate 3131 are respectively connected to the end of the guide plate 3121 of one tab shaping structure 312 near the pole group. The support plate 3132 is connected to the middle of the connecting plate 3131 and is disposed on the end face of the connecting plate 3131 near the cover plate body 100. The support plate 3132 abuts against the cover plate body 100, thereby providing support for the two adjacent tab shaping structures 312.

[0062] Referring again to Figure 4, along the first direction, the distance between the support plate 3132 and the tab shaping structure 312 is e, and the range of values ​​for e is... For example, the value of e can be 0.5mm, 1.0mm, 5mm, 10mm, 15mm, or 20mm, and can be adjusted according to the dimensions of the second plastic part 300 along the first direction. These values ​​will not be listed here. It should be noted that the value of e should not be too small, otherwise the connecting plate 3131 will be too sharp and may easily damage the electrode tabs or electrode assembly. The value of e should also not be too large, otherwise it will occupy the space of the electrode tab shaping structure 312 along the first direction, increasing the height of the electrode tab shaping structure 312 along the second direction and potentially damaging the electrode assembly.

[0063] Along the second direction, the distance between the end face of the connecting plate 3131 facing away from the cover plate body 100 and the end face of the second plastic part body 310 facing away from the cover plate body 100 is f, and the range of values ​​for f is... For example, the value of f can be 0mm, 0.5mm, 1.0mm, 1.5mm, or 2.0mm. It is important to note that the value of f cannot be less than 0mm; otherwise, the tab shaping structure 312 will protrude from the end face of the second plastic body 310 near the electrode assembly, easily damaging the electrode assembly. The value of f should also not be too large; otherwise, the tilt angle of the guide plate 3121 will be too large, the tab structure will be too loose, the tab shaping structure 312 will not effectively shape the tab, resulting in a poor tab shape and a high risk of short circuits.

[0064] Referring to Figures 1, 4, and 5, in this embodiment, a double insulation structure is also provided between the tab and the cover plate body 100. Specifically, a first flange 220 is provided circumferentially in the first through hole 211, extending into the first mounting hole 110 along a second direction. A second flange 320 is provided circumferentially in the second through hole 311, extending into the first mounting hole 110 in a direction close to the first flange 220 and connecting with the first flange 220. The second flange 320 is sleeved outside the first flange 220 and fits against the inner wall of the first mounting hole 110. The tab is accommodated in the first through hole 211 inside the first flange 220. There are two layers of insulation structure (first flange 220 and second flange 320) between the tab and the cover plate body 100, resulting in good insulation and high battery safety.

[0065] In this embodiment, a recessed groove 120 is provided on the end face of the cover plate body 100 facing away from the second plastic part 300. A circumferential overlapping portion 230 is provided on the first plastic part body 210, the overlapping portion 230 being annular and surrounding the first plastic part body 210. The overlapping portion 230 is embedded in the recessed groove 120 and fits against the bottom wall of the recessed groove 120. On one hand, the overlapping portion 230 can limit the first plastic part 200 along the axial direction of the first mounting hole 110 (the second direction, i.e., the Z-axis direction in Figure 1), ensuring accurate positioning between the first plastic part 200 and the cover plate body 100. On the other hand, the recessed groove 120 can further reduce the height of the battery cover plate assembly along the second direction, improving the space utilization of the entire battery pack and increasing energy density.

[0066] Wherein, along the second direction (that is, the Z-axis direction shown in Figure 1), the thickness of the cover plate body 100 is H, and the distance between the end face of the overlapping part 230 away from the second plastic part 300 and the end face of the cover plate body 100 away from the second plastic part 300 is b, and the value range of b satisfies: For example, the value of H ranges from 1mm to 3mm. When H is 1mm, the value of b can be 0mm or 0.5mm. When H is 3mm, the value of b can be 0mm, 0.5mm, 1mm, or 1.5mm. It is important to note that the value of b should not be too large. If the value of b is greater than 0.5H, the depth of the recess 120 will be too large, affecting the structural strength of the cover body 100. The cover body 100 is prone to deformation or breakage when subjected to impacts, leading to battery failure. The value of b should also not be too small. If the value of b is less than 0mm, it indicates that the end face of the overlapping part 230 facing away from the second plastic part 300 extends beyond the recess 120, which may affect the assembly between the first plastic part 200 and other structural components.

[0067] Optionally, along the first direction (i.e., the Y-axis direction shown in Figure 1), the width of the overlapping portion 230 is c, and the range of values ​​for c satisfies: For example, the value of c can be 0mm, 1mm, 2mm, 5mm, 8mm, or 10mm. By controlling the width c of the overlap 230 within the above range, the assembly structure between the first plastic part 200 and the cover plate body 100 can be kept stable, and the weight of the first plastic part 200 can be relatively reduced, thus reducing material costs. It should be noted that when the width c of the overlap 230 is 0mm, the circumferential edge of the first plastic part body 210 directly overlaps the cover plate body 100, which also ensures successful assembly of the first plastic part 200 and the cover plate body 100. In addition, when the width c of the overlap 230 is greater than 10mm, it may occupy more space in the recess 120, affecting the assembly between the cover plate body 100 and other structural components.

[0068] Optionally, along a third direction (i.e., the X-axis direction shown in Figure 1), the width of the overlap 230 is also c, and the range of values ​​for c satisfies: The width of the overlapping portion 230 along the first direction and the width of the overlapping portion 230 along the third direction can be equal or unequal, as long as the value of the width c of the overlapping portion 230 is within the above range.

[0069] Referring to Figure 6, the first plastic body 210 has a connecting rib 240 and a third flange 250 on the side opposite to the cover body 100. The third flange 250 is located circumferentially to the first through hole 211 and extends in the opposite direction to the first flange 220. The third flange 250 corresponds one-to-one with the first flange 220, and both the third flange 250 and the first flange 220 are annular. There are two connecting ribs 240, and each connecting rib 240 is connected to a third flange 250 at both ends. The connecting ribs 240, the third flanges 250, and the first plastic body 210 together form a mounting groove 241. The electrode post is generally flat, and at least a portion of the electrode post is embedded in the mounting groove 241. This further reduces the height of the battery cover assembly along the second direction, thereby improving space utilization and increasing the energy density of the entire battery pack. Optionally, the second flange 320 on the second plastic body 310 is also annular.

[0070] In some embodiments, the first plastic part 200 and the cover plate body 100, and the second plastic part 300 and the cover plate body 100, can be fixed by heat fusion.

[0071] Referring again to Figures 1 and 5, a first fixing groove 130 is provided on the bottom wall of the settling tank 120. A first fusion column 260 is provided on the end face of the first plastic part body 210 facing the cover plate body 100. The first fusion column 260 is inserted into the first fixing groove 130. One end of the first fusion column 260 inserted into the first fixing groove 130 is locked into the first fixing groove 130 after ultrasonic heat fusion, thereby realizing the connection between the first plastic part 200 and the cover plate body 100. Optionally, the first fixing groove 130 can be set as a trapezoidal groove or a stepped groove with a gradually narrowing inlet, so as to improve the connection strength between the first fusion column 260 and the first fixing groove 130. In addition, the bottom wall of the sink 120 may be provided with multiple first fixing grooves 130, and correspondingly, multiple first fusion pillars 260 are also provided on the first plastic part 200. The first fixing grooves 130 and the first fusion pillars 260 correspond one-to-one, thereby improving the connection strength between the first plastic part 200 and the cover plate body 100, and also improving the uniformity of the force on the first plastic part 200. For example, in this embodiment, two first fusion pillars 260 are provided on the end face of the first plastic part body 210 facing the cover plate body 100, and two first fixing grooves 130 are correspondingly provided in the sink 120. In other embodiments, the number and arrangement of the first fusion pillars 260 and the first fixing grooves 130 can also be flexibly adjusted as needed, and this embodiment does not limit this.

[0072] A second fixing groove 140 is provided on the end face of the cover plate body 100 facing the second plastic part 300, and a second fusion column 330 is provided on the end face of the second plastic part body 310 facing the cover plate body 100. The second fusion column 330 is inserted into the second fixing groove 140, and one end of the second fusion column 330 inserted into the second fixing groove 140 is snapped into the second fixing groove 140 after ultrasonic heat fusion, thereby realizing the connection between the second plastic part 300 and the cover plate body 100. Optionally, the second fixing groove 140 can be set as a trapezoidal groove or a stepped groove with a gradually narrowing inlet, so as to improve the connection strength between the second fusion column 330 and the second fixing groove 140. In addition, a plurality of second fixing grooves 140 may be provided on the end face of the cover plate body 100 facing the second plastic part 300. The plurality of second fixing grooves 140 are arranged at intervals near the periphery of the cover plate body 100. Correspondingly, a plurality of second fusion pillars 330 are also provided on the second plastic part body 310. The plurality of second fusion pillars 330 are arranged at intervals near the periphery of the second plastic part body 310. The second fixing grooves 140 and the second fusion pillars 330 correspond one-to-one, thereby improving the connection strength between the second plastic part 300 and the cover plate body 100, and also improving the uniformity of the force on the second plastic part 300. For example, in this embodiment, six second fusion pillars 330 are provided on the end face of the second plastic part body 310 facing the cover plate body 100, and six second fixing grooves 140 are correspondingly provided on the cover plate body 100. In other embodiments, the number and arrangement of the second fusion pillars 330 and the second fixing grooves 140 can also be flexibly adjusted as needed, and this embodiment does not limit this.

[0073] Optionally, the battery cover assembly in this embodiment further includes an explosion-proof valve 400. A second mounting hole 150 is provided on the cover body 100, and the explosion-proof valve 400 is disposed within the second mounting hole 150. A vent hole 340 is provided on the second plastic body 310 corresponding to the position of the second mounting hole 150. The projection of the vent hole 340 on the cover body 100 along the second direction (the Z-axis direction shown in Figure 1) coincides with the projection of the explosion-proof valve 400 on the cover body 100. Therefore, when the pressure inside the battery casing exceeds the opening pressure of the explosion-proof valve 400, high-temperature, high-pressure gas and liquid can be discharged from the battery through the vent hole 340 and the explosion-proof valve 400, avoiding the risk of explosion and ensuring high safety. In addition, crisscrossing support ribs 151 are also provided within the second mounting hole 150, which can support the explosion-proof valve 400 and improve its installation strength. Multiple vent holes 340 can be provided on the second plastic body 310 at intervals to increase the flow area, so that high-temperature and high-pressure gases and liquids can be discharged quickly and flow smoothly.

[0074] Optionally, in some embodiments, the cover plate body 100 is further provided with a first injection hole 160, and the second plastic body 310 is provided with a second injection hole (not shown in the figure) at a position corresponding to the first injection hole 160. The projection of the first injection hole 160 on the cover plate body 100 along the second direction coincides with the projection of the second injection hole on the cover plate body 100. After the battery cover plate assembly is assembled with the housing, electrolyte can be injected into the housing through the first injection hole 160 and the second injection hole so that the electrode assembly can be immersed in the electrolyte. After the injection is completed, an injection plug can be inserted into the first injection hole 160 and / or the second injection hole to seal the first injection hole 160 and / or the second injection hole and prevent electrolyte leakage. Exemplarily, the injection plug is made of a material with elastic deformation capability, such as rubber.

[0075] This embodiment also provides a battery, including a casing, an electrode assembly, and the aforementioned battery cover assembly. An opening is provided on one side of the casing, through which the electrode assembly is inserted into the casing. The battery cover assembly is disposed at the opening of the casing and welded to the casing. The battery cover assembly and the casing form a closed accommodating space to encapsulate the electrode assembly within the accommodating space. By employing the aforementioned battery cover assembly, the electrode posts are located outside the casing, without occupying internal space, increasing the volume of the electrode assembly and thus the energy density of the battery. Furthermore, the tab shaping structure 312 on the second plastic body 310 can retract the tabs into the second through hole 311, providing good guidance when the tabs protrude through the second through hole 311. The overall shape of the tabs is good, and short-circuit connections between the tabs and the casing are less likely to occur, resulting in good battery safety. In addition, there are two layers of insulating structure, a first flange 220 and a second flange 320, between the tabs of the electrode assembly and the cover body 100, providing excellent insulation performance for the battery cover assembly.

[0076] Table 1 below provides several specific implementation examples. In each implementation example, the included angle α between the axis of the guide plate 3121 of the second plastic part 200 and the axis of the second through hole 311 is different, while the other parameters are the same.

[0077] Table 1

[0078]

[0079] The results above show that the value of the included angle α in Implementation Case 1 is less than The minimum value of ° indicates that the tilt angle of the guide plate 3121 is small. CT scans show that the retraction and shaping effect of the electrode tabs is poor. The electrode tabs are inserted upside down into the electrode group, causing a short circuit in the electrode group, resulting in a defective battery product.

[0080] In Implementation Case 11, the value of the included angle α is greater than The maximum value is that the tilt angle of the guide plate 3121 is too large, which cannot play a good role in gathering and shaping the tabs. CT shows that the shape of the tabs inside the battery is poor, and the battery product is unqualified.

[0081] In Implementation Cases 2, 3, 4, 5, 6, 7, 8, 9, and 10, the value of the included angle α is... Within the specified range, the tilt angle of the guide plate 3121 is appropriate, which can effectively gather and shape the tabs. CT scans show that the tabs are in good shape inside the battery, the tabs are not inserted into the electrode assembly, the electrode assembly short circuit test is passed, and the battery product is qualified.

[0082] Example 2

[0083] This embodiment provides a battery cover assembly, which differs from the battery cover assembly in Embodiment 1 in that the assembly structure between the first flange 220 and the second flange 320 in the battery cover assembly is different.

[0084] Specifically, referring to Figures 7 and 8, in this embodiment, the inner diameter of the first mounting hole 110 is equal to the outer diameter of the first flange 220, and the inner diameter of the first flange 220 is equal to the outer diameter of the second flange 320. The first flange 220 is sleeved on the outside of the second flange 320, and the peripheral sidewall of the first flange 220 fits against the inner wall of the first mounting hole 110. The peripheral sidewall of the second flange 320 fits against the inner wall of the first flange 220. The electrode tab is accommodated in the first through hole 211 and the second through hole 311. Thus, there are two layers of insulation structure (the first flange 220 and the second flange 320, both of which are annular) between the electrode tab and the cover plate body 100. The insulation effect between the electrode tab and the cover plate body 100 is good, and the battery has good safety.

[0085] This embodiment also provides a battery, including a casing, an electrode assembly, and the aforementioned battery cover assembly. An opening is provided on one side of the casing, through which the electrode assembly is inserted into the casing. The battery cover assembly is disposed at the opening of the casing and welded to the casing. The battery cover assembly and the casing form a closed accommodating space to encapsulate the electrode assembly within the accommodating space. By employing the aforementioned battery cover assembly, the electrode posts are located outside the casing, without occupying internal space, increasing the volume of the electrode assembly and thus the energy density of the battery. Furthermore, the tab shaping structure 312 on the second plastic body 310 can retract the tabs into the second through hole 311, providing good guidance when the tabs protrude through the second through hole 311. The overall shape of the tabs is good, and short-circuit connections between the tabs and the casing are less likely to occur, resulting in good battery safety. In addition, there are two layers of insulating structure, a first flange 220 and a second flange 320, between the tabs of the electrode assembly and the cover body 100, providing excellent insulation performance for the battery cover assembly.

[0086] The remaining structures in this embodiment are the same as those in Embodiment 1, and will not be described in detail here.

[0087] Example 3

[0088] This embodiment provides a battery cover assembly, which differs from the battery cover assembly in Embodiment 1 in that the assembly structure between the first flange 220 and the second flange 320 in the battery cover assembly is different.

[0089] Specifically, referring to Figures 9 and 10, in this embodiment, the inner diameter of the first mounting hole 110 is equal to the outer diameter of the first flange 220, the outer diameter of the first flange 220 is larger than the outer diameter of the second flange 320, and the inner diameter of the first flange 220 is smaller than the inner diameter of the second flange 320. A first insertion groove 221 is provided on the end face of the first flange 220 facing the second plastic part 300. The second flange 320 extends into the first insertion groove 221. Along the radial direction of the first mounting hole 110 (the Y-axis direction shown in Figure 9), both sides of the second flange 320 are respectively attached to the sidewalls of the first insertion groove 221, and the peripheral sidewall of the first flange 220 is attached to the inner wall of the first mounting hole 110. The electrode tab is accommodated in the first through hole 211. Thus, there are two layers of insulation structure (first flange 220 and second flange 320) between the electrode tab and the cover plate body 100, resulting in good insulation between the electrode tab and the cover plate body 100 and good battery safety. Furthermore, due to the setting of the first insertion slot 221, the positioning between the first plastic part 200 and the second plastic part 300 can be more accurate, which is conducive to improving the assembly accuracy of the battery cover assembly.

[0090] This embodiment also provides a battery, including a casing, an electrode assembly, and the aforementioned battery cover assembly. An opening is provided on one side of the casing, through which the electrode assembly is inserted into the casing. The battery cover assembly is disposed at the opening of the casing and welded to the casing. The battery cover assembly and the casing form a closed accommodating space to encapsulate the electrode assembly within the accommodating space. By employing the aforementioned battery cover assembly, the electrode posts are located outside the casing, without occupying internal space, increasing the volume of the electrode assembly and thus the energy density of the battery. Furthermore, the tab shaping structure 312 on the second plastic body 310 can retract the tabs into the second through hole 311, providing good guidance when the tabs protrude through the second through hole 311. The overall shape of the tabs is good, and short-circuit connections between the tabs and the casing are less likely to occur, resulting in good battery safety. In addition, there are two layers of insulating structure, a first flange 220 and a second flange 320, between the tabs of the electrode assembly and the cover body 100, providing excellent insulation performance for the battery cover assembly.

[0091] The remaining structures in this embodiment are the same as those in Embodiment 1, and will not be described in detail here.

[0092] Example 4

[0093] This embodiment provides a battery cover assembly, which differs from the battery cover assembly in Embodiment 1 in that the assembly structure between the first flange 220 and the second flange 320 in the battery cover assembly is different.

[0094] Specifically, referring to Figures 11 and 12, in this embodiment, the inner diameter of the first mounting hole 110 is equal to the outer diameter of the second flange 320, the outer diameter of the second flange 320 is greater than the outer diameter of the first flange 220, and the inner diameter of the second flange 320 is smaller than the inner diameter of the first flange 220. A second insertion groove 321 is provided on the end face of the second flange 320 facing the first plastic part 200. The first flange 220 extends into the second insertion groove 321. Along the radial direction of the first mounting hole 110 (the Y-axis direction shown in Figure 11), both sides of the first flange 220 are respectively attached to the sidewalls of the second insertion groove 321, and the peripheral sidewall of the second flange 320 is attached to the inner wall of the first mounting hole 110. The electrode is accommodated in the first through hole 211 and the second through hole 311. Therefore, there are two layers of insulation structure (first flange 220 and second flange 320) between the electrode tab and the cover plate body 100, resulting in good insulation between the electrode tab and the cover plate body 100 and good battery safety. Furthermore, due to the setting of the second insertion groove 321, the positioning between the first plastic part 200 and the second plastic part 300 can be more accurate, which is beneficial to improving the assembly accuracy of the battery cover plate assembly.

[0095] This embodiment also provides a battery, including a casing, an electrode assembly, and the aforementioned battery cover assembly. An opening is provided on one side of the casing, through which the electrode assembly is inserted into the casing. The battery cover assembly is disposed at the opening of the casing and welded to the casing. The battery cover assembly and the casing form a closed accommodating space to encapsulate the electrode assembly within the accommodating space. By employing the aforementioned battery cover assembly, the electrode posts are located outside the casing, without occupying internal space, increasing the volume of the electrode assembly and thus the energy density of the battery. Furthermore, the tab shaping structure 312 on the second plastic body 310 can retract the tabs into the second through hole 311, providing good guidance when the tabs protrude through the second through hole 311. The overall shape of the tabs is good, and short-circuit connections between the tabs and the casing are less likely to occur, resulting in good battery safety. In addition, there are two layers of insulating structure, a first flange 220 and a second flange 320, between the tabs of the electrode assembly and the cover body 100, providing excellent insulation performance for the battery cover assembly.

[0096] The remaining structures in this embodiment are the same as those in Embodiment 1, and will not be described in detail here.

Claims

1. A battery cover assembly, comprising: The cover plate body is provided with a first mounting hole; A first plastic part is disposed on one side of the cover plate body. The first plastic part includes a first plastic part body and a first through hole is provided on the first plastic part body. The second plastic part is disposed on the other side of the cover plate body. The second plastic part includes a second plastic part body, on which a second through hole and an electrode ear shaping structure are provided. The electrode ear shaping structure is disposed in the circumferential direction of the second through hole, and the electrode ear shaping structure is located on the side of the second plastic part body away from the cover plate body. The electrode post is located on the side of the first plastic part away from the cover plate body. The electrode lug of the electrode group passes through the second through hole, the first mounting hole, and the first through hole and is connected to the electrode post.

2. The battery cover assembly according to claim 1, wherein, The electrode tab shaping structure includes two guide plates, which are respectively disposed on both sides of the second through hole along the first direction. The two guide plates are inclined in a direction away from the axis of the second through hole. A flared mouth with a gradually widening opening is formed between the two guide plates in a direction away from the second through hole. The larger end of the flared mouth faces the electrode assembly, and the smaller end of the flared mouth is connected to the second plastic body. The electrode tab is inserted into the flared mouth. The angle between the guide plate and the axis of the second through hole is α, and the value of α ranges from [value missing]. 。 3. The battery cover assembly according to claim 1, wherein, Along the first direction, the first through holes on the first plastic body are provided at intervals, and the second through holes and the tab shaping structure on the second plastic body are provided in multiples, and the first through holes, the second through holes and the tab shaping structure correspond one-to-one.

4. The battery cover assembly according to claim 1, wherein, The second plastic part body has a support structure on the side near the cover plate body. The support structure includes a connecting plate and a support plate. The connecting plate is connected to the tab shaping structure. The support plate is disposed on the end face of the connecting plate near the cover plate body and abuts against the cover plate body.

5. The battery cover assembly according to claim 4, wherein, Along the first direction, the distance between the support plate and the tab shaping structure is e, and the value of e ranges from... ; And / or, along the second direction, the end face of the connecting plate opposite to the cover plate body is connected to the second plastic part. The distance between the end face of the main body and the end face of the cover plate body is f, and the value of f ranges from 1 to 2. 。 6. The battery cover assembly according to claim 1, wherein, The first through hole has a first flange in its circumferential direction, which extends into the first mounting hole. The second through hole has a second flange in its circumferential direction, which extends into the first mounting hole and connects with the first flange. One of the first flange and the second flange is in contact with the inner wall of the first mounting hole.

7. The battery cover assembly according to claim 6, wherein, The second flange is sleeved outside the first flange, and the peripheral sidewall of the second flange fits against the inner wall of the first mounting hole; Alternatively, the first flange is sleeved outside the second flange, and the peripheral sidewall of the first flange fits against the inner wall of the first mounting hole; Alternatively, a first insertion groove is provided on the end face of the first flange facing the second plastic part, the second flange extends into the first insertion groove, and the peripheral sidewall of the first flange fits against the inner wall of the first mounting hole. Alternatively, a second insertion groove is provided on the end face of the second flange facing the first plastic part, the first flange extends into the second insertion groove, and the peripheral sidewall of the second flange fits against the inner wall of the first mounting hole.

8. The battery cover assembly according to claim 1, wherein, The cover plate body has a recessed groove on the end face opposite to the second plastic part, and the first plastic part body has an overlapping part in the circumferential direction. The overlapping part is embedded in the recessed groove and fits against the bottom wall of the recessed groove. Wherein, along the second direction, the thickness of the cover plate body is H, and the distance between the end face of the overlapping portion facing away from the second plastic part and the end face of the cover plate body facing away from the second plastic part is b, and the value range of b satisfies: ； And / or, along the first direction, the width of the overlap is c, and the range of values ​​for c satisfies: 。 9. The battery cover assembly according to claim 1, wherein, The first plastic part is heat-fused to the cover plate body, and the second plastic part is heat-fused to the cover plate body.

10. A battery comprising a housing, an electrode assembly, and a battery cover assembly according to any one of claims 1-9, the battery cover assembly being encapsulated at an opening of the housing, the electrode assembly being disposed within the housing.

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