A battery cover plate assembly and a battery

Abstract

The application relates to the technical field of batteries, and particularly discloses a battery cover plate assembly and a battery. The battery cover plate assembly comprises a cover plate body, a first plastic part, a second plastic part and a pole, the first plastic part and the second plastic part are arranged on the two sides of the cover plate body respectively, and the pole is arranged on the side, away from the cover plate body, of the first plastic part. The tabs of a pole group are connected with the pole after penetrating through the second plastic part, the cover plate body and the first plastic part. The pole is arranged on the side, away from the cover plate body, of the first plastic part, so that the space inside the shell is not occupied, the volume of the pole group is increased, the space utilization rate inside the shell is high, and the energy density of the battery is large. Further, the tab shaping structure on the second plastic part can fold the tabs, the overall shape of the tabs is good, the tabs are not easy to be short-circuited and overlapped with the shell, and the safety of the battery is high. The application also provides a battery comprising the above battery cover plate assembly.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more particularly to a battery cover assembly and a battery. Background Technology

[0002] 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.

[0003] Currently available battery cover assemblies generally include a riveting block, an upper plastic component, a terminal post, a cover body, a lower plastic component, and a sealing ring. The sealing ring is fitted over the terminal post. The post's cylindrical portion passes sequentially through the lower plastic component, the cover body, and the upper plastic component from one side of the cover body before connecting to the riveting block. The plate-shaped portion of the terminal post is pressed against the lower plastic component. After the battery cover assembly is installed with the housing, the plate-shaped portion of the terminal post and the lower plastic component 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 component have a certain height, they occupy internal space in the housing, reducing the space available for the electrode assembly and hindering efficient space utilization, resulting in low battery energy density. Furthermore, when existing tabs are led out from the electrode assembly and connected to the plate-shaped portion of the terminal post, they require C-shaped or S-shaped bends. Due to a lack of support, the tab's shape within the housing may deform, posing a short-circuit risk between the tab and the housing. Summary of the Invention

[0004] The purpose of this invention is to provide a battery cover assembly and a battery, wherein the terminals are arranged outside the housing, without occupying the internal space of the housing, increasing the volume of the electrode assembly, improving space utilization, and increasing the energy density of the battery. Furthermore, the electrode tabs have a good shape, making it less likely to cause short circuits due to contact with the housing, thus ensuring high battery safety.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] On one hand, the present invention provides a battery cover assembly, comprising:

[0007] The cover plate body is provided with a first mounting hole;

[0008] 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.

[0009] 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.

[0010] 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.

[0011] 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.

[0012] The included angle between the guide plate and the axis of the second through hole is α, and the value of α is in the range of 45°≤α≤87°.

[0013] 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.

[0014] 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.

[0015] Optionally, along the first direction, the distance between the support plate and the tab shaping structure is e, where the value of e ranges from 0.5mm to e and from 20mm to 0.5mm to 20mm.

[0016] And / or, along the second direction, the distance between the end face of the connecting plate away from the cover plate body and the end face of the second plastic part body away from the cover plate body is f, and the value of f is in the range of 0mm≤f≤2mm.

[0017] 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.

[0018] 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;

[0019] 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;

[0020] 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.

[0021] 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.

[0022] 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.

[0023] Wherein, along the second direction, the thickness of the cover plate body is H, and the distance between the end face of the overlapping part away from the second plastic part and the end face of the cover plate body away from the second plastic part is b, and the value range of b satisfies: 0mm≤b≤0.5H;

[0024] And / or, along the first direction, the width of the overlap is c, and the value of c is within the range of: 0mm≤c≤10mm.

[0025] 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.

[0026] On the other hand, the present invention 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.

[0027] The beneficial effects of this invention are as follows:

[0028] This invention 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 opposite 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. Because the terminal post is disposed on the side of the first plastic part facing away from the cover body, it does not occupy internal space of the housing, greatly saving internal space. The volume of the electrode assembly is increased, and the internal space utilization of the housing is high, which helps to improve the energy density of the battery. Furthermore, the second plastic part is provided with an electrode tab shaping structure, which can fold the electrode tabs together, resulting in a good overall shape of the electrode tabs. In addition, the electrode tab shaping structure can also support the electrode tabs, preventing short-circuit contact between the electrode tabs and the housing, and ensuring battery safety.

[0029] The present invention 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, reducing the likelihood of short-circuit connections between the tabs and the casing, and ensuring good battery safety. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0031] Figure 1 This is an exploded view of the battery cover assembly provided in Embodiment 1 of the present invention;

[0032] Figure 2 This is a top view of the battery cover assembly provided in Embodiment 1 of the present invention;

[0033] Figure 3 for Figure 2 Cross-sectional view of section AA;

[0034] Figure 4 for Figure 3 A magnified view of a section at point B in the middle;

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

[0036] Figure 6 This is a schematic diagram of the structure of the first plastic part provided in Embodiment 1 of the present invention;

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

[0038] Figure 8 for Figure 7 A magnified view of a section at point C;

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

[0040] Figure 10 for Figure 9 A magnified view of a section at point D;

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

[0042] Figure 12 for Figure 11 A magnified view of a section at point E in the middle.

[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] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] In the description of this invention, 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 the invention 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 the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions. Furthermore, "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.

[0050] In the description of this invention, it should be noted that, unless otherwise explicitly 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 of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0051] Embodiments of the present invention 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 the present invention, and should not be construed as limiting the present invention.

[0052] Example 1

[0053] like Figures 1-4 As shown, 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.

[0054] 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.

[0055] Furthermore, 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, providing 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 contact 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 in the second through hole 311 along the first direction ( Figures 1-3 The guide plates 3121 are inclined in a direction away from the axis of the second through hole 311 (as shown in the Y-axis direction). Along the direction away from the second through hole 311, a gradually widening flared opening 3122 is formed between the two guide plates 3121. The larger end of the flared opening 3122 faces the electrode assembly, and the smaller end of the flared opening 3122 is connected to the second plastic body 310 circumferentially connected to the second through hole 311. During installation, the electrode tab is inserted into the second through hole 311 from the larger end of the flared opening 3122. The opening of the flared opening 3122 gradually narrows along the direction close to the second through hole 311. Therefore, when the electrode tab is inserted into the flared opening 3122, the guide plates 3121 on both sides of the flared opening 3122 can effectively retract 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 within the housing, resulting in a good overall shape.

[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 properly houses the tab within the second through hole 311. It should be noted that when the value of α is too large, it will not have a good shaping effect on the tab; when the value of α is too small, the tab is easily inserted backwards into the electrode assembly, causing a short circuit, and will increase the height of the second plastic part 300 along the second direction (i.e., the second direction is...). Figure 1 , Figure 3 The Z-axis direction shown in the figure is not conducive to improving the energy density of the battery.

[0058] Furthermore, this embodiment will be described using an example of two electrode groups within the housing. 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 the two electrode posts are also located on the same side. Two first plastic parts 200 and two electrode posts are provided, with the two first plastic parts 200 respectively located along a third direction of the cover plate body 100 (…). Figure 1 , Figure 2 At both ends of the two first plastic parts 200 (in the X-axis direction shown), the poles on the side of the two first plastic parts 200 away from the cover plate body 100 are respectively the positive pole and the negative pole. Each first plastic part 200 has two first through holes 211 on its first plastic part body 210. The two first through holes are along the first direction ( Figure 1 , Figure 2 The two first through holes 211 on the first plastic part 200 are respectively for the positive electrode tabs of the two electrode groups to pass through, or the two first through holes 211 on the first plastic part 200 are respectively for 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. Further, 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] See also Figure 4 Along the first direction, the distance between the support plate 3132 and the tab shaping structure 312 is denoted as e, and the value of e ranges from 0.5mm to e ≤ 20mm. 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 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 tab or electrode assembly. Of course, the value of e should also not be too large, otherwise it will occupy the space of the tab shaping structure 312 along the first direction, increasing the height of the tab shaping structure 312 along the second direction and potentially damaging the electrode assembly.

[0063] Furthermore, 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 value of f is in the range of 0mm≤f≤2mm. For example, the value of f can be 0mm, 0.5mm, 1.0mm, 1.5mm or 2.0mm. It should be noted 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 part body 310 near the electrode assembly, which may easily damage 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 structure of the tab will be relatively loose, the shaping effect of the tab shaping structure 312 on the tab will be poor, the tab shape will be poor, and short circuits may easily occur.

[0064] See Figure 1 , Figure 4 and Figure 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, and the first flange 220 extends into the first mounting hole 110 along the second direction. A second flange 320 is provided circumferentially in the second through hole 311, and the second flange 320 also extends into the first mounting hole 110 in a direction close to the first flange 220 and connects with the first flange 220. The second flange 320 is sleeved on the outside of 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, which has a good insulation effect and high battery safety.

[0065] Furthermore, 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, and an overlapping portion 230 is provided circumferentially on the first plastic part body 210. The overlapping portion 230 is annular and surrounds 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 the one hand, the overlapping portion 230 can be arranged along the axial direction of the first mounting hole 110 (the second direction, i.e., the second direction). Figure 1 The first plastic part 200 is limited in the Z-axis direction to ensure accurate positioning between the first plastic part 200 and the cover body 100; on the other hand, by setting the sink 120, the height of the battery cover assembly along the second direction can be further reduced, thereby improving the space utilization of the entire battery pack and increasing the energy density.

[0066] Among them, along the second direction (that is...) Figure 1 (As shown in the Z-axis direction), the thickness of the cover body 100 is H. The distance between the end face of the overlapping portion 230 facing away from the second plastic part 300 and the end face of the cover body 100 facing away from the second plastic part 300 is b. The value of b satisfies the following range: 0mm ≤ b ≤ 0.5H. 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 should be noted 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 large, affecting the structural strength of the cover body 100. When the cover body 100 is subjected to impact, it is easy to deform or break, leading to battery failure. Of course, the value of b should not be too small. If the value of b is less than 0 mm, it indicates that the end face of the overlapping part 230 away from the second plastic part 300 exceeds the groove 120, which may affect the assembly between the first plastic part 200 and other structural parts.

[0067] Optionally, along the first direction (i.e. Figure 1(As shown in the Y-axis direction), the width of the overlapping portion 230 is c, and the value of c is within the range of 0mm ≤ c ≤ 10mm. For example, the value of c can be 0mm, 1mm, 2mm, 5mm, 8mm, or 10mm. By controlling the width c of the overlapping portion 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 overlapping portion 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. Furthermore, when the width c of the overlapping portion 230 is greater than 10mm, it may occupy more space within the recess 120, affecting the assembly between the cover plate body 100 and other structural components.

[0068] Optionally, along a third direction (i.e. Figure 1 As shown in the X-axis direction, the width of the overlapping portion 230 is also c, and the value of c is within the range of 0mm≤c≤10mm. 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] Further, see 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, so as to improve space utilization and increase 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] See also Figure 1 and Figure 5A 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 settling tank 120 can be provided with multiple first fixing grooves 130, and correspondingly, multiple first fusion columns 260 are also provided on the first plastic part 200. The first fixing grooves 130 and the first fusion columns 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 molten 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. Of course, in other embodiments, the number and arrangement of the first molten pillars 260 and the first fixing grooves 130 can be flexibly adjusted as needed, and this embodiment does not limit this.

[0072] Furthermore, 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. Of course, in other embodiments, the number and arrangement of the second fusion pillars 330 and the second fixing grooves 140 can 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. The cover body 100 has a second mounting hole 150, and the explosion-proof valve 400 is disposed within the second mounting hole 150; the second plastic body 310 has a vent 340 corresponding to the position of the second mounting hole 150, extending along a second direction ( Figure 1 The projection of the vent 340 (in the Z-axis direction shown) on the cover body 100 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 gases and liquids can be discharged from the battery through the vent 340 and the explosion-proof valve 400, avoiding the risk of explosion and ensuring high safety. In addition, the second mounting hole 150 is provided with crisscrossing support ribs 151, which support the explosion-proof valve 400 and improve its installation strength. Furthermore, multiple vent holes 340 on the second plastic body 310 can be spaced apart to increase the flow area, allowing high-temperature, high-pressure gases and liquids to be discharged quickly and 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 in Implementation Case 1, the value of the included angle α is less than the minimum value of 45°≤α≤87°, the tilt angle of the guide plate 3121 is small, the CT scan shows that the retraction and shaping effect of the electrode tab is poor, the electrode tab is inserted into the electrode group in reverse, causing a short circuit in the electrode group, and the battery product is unqualified.

[0080] In Implementation Case 11, the value of the included angle α is greater than the maximum value of 45°≤α≤87°. 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 tabs have a poor shape inside the battery, and the battery product is unqualified.

[0081] In Implementation Cases 2, 3, 4, 5, 6, 7, 8, 9, and 10, the included angle α is within the range of 45°≤α≤87°. The tilt angle of the guide plate 3121 is appropriate and can play a good role in gathering and shaping the tabs. CT shows that the tabs are in good shape inside the battery. The tabs are not inserted into the electrode group. The electrode group 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, see Figure 7 and Figure 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, see Figure 9 and Figure 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 greater 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. Figure 9 (As shown in the Y-axis direction), the two 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, and the insulation effect between the electrode tab and the cover plate body 100 is good, resulting in good battery safety. Furthermore, due to the setting of the first insertion groove 221, 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.

[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, see Figure 11 and Figure 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. Figure 11 (As shown in the Y-axis direction), the two 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 tab is accommodated in the first through hole 211 and the second through hole 311. 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, and the insulation effect between the electrode tab and the cover plate body 100 is good, resulting in 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.

[0097] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A battery cover assembly, characterized in that, include: 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. 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 included angle between the guide plate and the axis of the second through hole is α, and the value of α is in the range of 45°≤α≤87°.

2. The battery cover assembly according to claim 1, characterized in that, 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.

3. The battery cover assembly according to claim 1, characterized in that, 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.

4. The battery cover assembly according to claim 3, characterized in that, Along the first direction, the distance between the support plate and the tab shaping structure is e, and the value of e ranges from 0.5mm ≤ e ≤ 20mm; And / or, along the second direction, the distance between the end face of the connecting plate away from the cover plate body and the end face of the second plastic part body away from the cover plate body is f, and the value of f is in the range of 0mm≤f≤2mm.

5. The battery cover assembly according to claim 1, characterized in that, 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.

6. The battery cover assembly according to claim 5, characterized in that, 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.

7. The battery cover assembly according to claim 1, characterized in that, 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 part away from the second plastic part and the end face of the cover plate body away from the second plastic part is b, and the value range of b satisfies: 0mm≤b≤0.5H; And / or, along the first direction, the width of the overlap is c, and the value of c is within the range of: 0mm≤c≤10mm.

8. The battery cover assembly according to claim 1, characterized in that, 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.

9. A battery, characterized in that, The device includes a housing, an electrode assembly, and a battery cover assembly according to any one of claims 1-8, wherein the battery cover assembly is encapsulated at an opening of the housing, and the electrode assembly is disposed within the housing.

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