Plastic part, battery cell and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a plastic part, a battery cell and a battery pack, the plastic part comprises a first plate body and a second plate body which are connected, one side, close to the second plate body, of the first plate body is provided with an inward first step, and the outer side surface of the first step is provided with at least one clamping bulge; the side, close to the first plate body, of the second plate body is provided with an inward second step, the second step is provided with a clamping through hole corresponding to the clamping protrusion, and the clamping protrusion is clamped in the clamping through hole. According to the plastic part disclosed by the utility model, a split structure of the first plate body and the second plate body is adopted, and mutual support between the first plate body and the second plate body is realized by clamping the clamping bulge of the first plate body and the clamping through hole of the second plate body, so that drooping and shaking of the first plate body and the second plate body on a battery cell can be reduced, and the production yield of the battery cell is improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to plastic parts, battery cells, and battery packs. Background Technology

[0002] A battery cell typically includes a housing, multiple electrode groups housed within the housing, and a cover assembly located on the top of the housing and electrically connected to the electrode groups. The cover assembly includes a cover body, a liquid injection port on the cover body, and an explosion-proof valve, among other structures. To prevent the cover body from conducting electricity through contact with the electrode groups, a plastic component is usually provided between the cover body and the electrode groups.

[0003] Plastic components include both one-piece and separate structures. For separate structures, the plastic component is positioned and supported by assembling it with the terminal post. However, the terminal post has limited ability to position and support the plastic component. For longer plastic components, the end furthest from the terminal post is not effectively supported, which can easily lead to excessive sag. Furthermore, the plastic component is prone to shaking and colliding with internal components of the battery cell, ultimately damaging the cell. Utility Model Content

[0004] In view of this, the present invention provides a plastic part, a battery cell, and a battery pack to solve the problem that in the case of a split plastic part, when the terminal post is used for assembly and limiting, the end of the plastic part away from the terminal post hangs too much, making the plastic part prone to shaking and causing damage to the battery cell.

[0005] In a first aspect, the present invention provides a plastic part, comprising: a first plate and a second plate connected to each other, wherein the first plate is provided with an inward first step on the side near the second plate, and the outer side of the first step is provided with at least one snap-fit ​​protrusion, and the second plate is provided with an inward second step on the side near the first plate, wherein the second step is provided with a snap-fit ​​through hole corresponding to the snap-fit ​​protrusion, and the snap-fit ​​protrusion snaps into the snap-fit ​​through hole.

[0006] Beneficial effects: This utility model utilizes the snap-fit ​​protrusion of the first plate and the snap-fit ​​through hole of the second plate to achieve limiting support, which can effectively support the first and second plates, improve their stability, prevent excessive sag, and avoid the first and second plates shaking inside the battery cell, causing damage to the battery cell, thereby improving the production yield of the battery cell. Furthermore, the first plate has a first step away from the cover plate, and the snap-fit ​​protrusion is located on the outer side of the first step; the second plate has a second step away from the cover plate, and the snap-fit ​​through hole is located on the second step. This ensures that the snap-fit ​​protrusion is located between the plastic part and the cover plate, preventing the snap-fit ​​protrusion from interfering with the cover plate or the electrode assembly of the battery cell.

[0007] In one alternative embodiment, the first step extends toward the second plate to form a protrusion, and the snap-fit ​​protrusion is provided on the protrusion;

[0008] The second step has a groove corresponding to the protrusion, and the snap-fit ​​hole is provided on the groove.

[0009] Beneficial effects: By setting a protrusion in the first step and a groove in the second step, and setting a snap-fit ​​protrusion on the protrusion and a snap-fit ​​through hole on the groove, the protrusion and groove are used to achieve primary limiting support, while the snap-fit ​​protrusion and snap-fit ​​through hole are used to achieve secondary limiting support. This can further improve the stability of the first and second plates, increase the production yield of the battery cell, and also help reduce manufacturing costs.

[0010] In one optional embodiment, in the height direction of the plastic part, the thickness H1 of the protrusion, the height H2 of the snap-fit ​​protrusion, and the thickness H3 of the plastic part satisfy H1+H2<H3.

[0011] Beneficial effects: By limiting the thickness H1 of the protrusion and the height H2 of the snap-fit ​​protrusion to be less than the thickness H3 of the plastic part, it is ensured that the height of the snap-fit ​​protrusion does not exceed the outer surface of the plastic part, thus preventing the snap-fit ​​protrusion from affecting the installation of the plastic part and the cover plate. The outer sides of the first and second steps generally correspond to the explosion-proof valve on the cover plate. Limiting the thickness H1 of the protrusion and the height H2 of the snap-fit ​​protrusion to be less than the thickness H3 of the plastic part also prevents interference between the snap-fit ​​protrusion and the explosion-proof valve, thereby improving the safety of the battery cell.

[0012] In one optional embodiment, the thickness H1 of the protrusion satisfies 0.5mm ≤ H1 ≤ 2.5mm;

[0013] And / or, the height H2 of the snap-fit ​​protrusion satisfies 1mm≤H2≤8mm.

[0014] Beneficial effects: By limiting the thickness of the protrusion, effective engagement between the protrusion and the groove, as well as effective installation of the plastic part and the cover plate, can be ensured. If the protrusion is too thick, the engagement protrusion may be too high, interfering with the cover plate, especially with the explosion-proof valve on the cover plate. If the protrusion is too thin, the limiting ability is insufficient, affecting the engagement effect between the protrusion and the groove. Similarly, by limiting the thickness of the engagement protrusion, effective engagement between the engagement protrusion and the engagement through hole, as well as effective installation of the plastic part and the cover plate, can be ensured. If the engagement protrusion is too thick, the engagement protrusion may be too high, interfering with the cover plate, especially with the explosion-proof valve on the cover plate. If the engagement protrusion is too thin, the limiting ability is insufficient, affecting the engagement effect between the engagement protrusion and the engagement through hole.

[0015] In one optional embodiment, in the length direction of the plastic part, the dimension L1 of the protrusion satisfies 5mm≤L1≤20mm;

[0016] And / or, in the width direction of the plastic part, the dimension L2 of the protrusion satisfies 3mm≤L2≤25mm.

[0017] Beneficial effects: By limiting the length and / or width of the protrusion, the effective engagement between the protrusion and the groove can be further ensured. If the length and / or width of the protrusion is too large, it is easy to deform and shrink during injection molding. If the protrusion is too thin, the limiting ability is insufficient, which affects the engagement effect between the protrusion and the groove.

[0018] In one alternative embodiment, the thickness H4 of the groove portion in the height direction of the plastic part satisfies 0.6mm≤H4≤2.5mm.

[0019] Beneficial effects: By limiting the thickness of the groove, it is possible to ensure effective engagement between the protrusion and the groove, as well as effective installation of the plastic part and the cover plate. If the groove is too thick, it is easy to deform and shrink during injection molding. If the groove is too thick or too thin, the limiting ability is insufficient, which affects the engagement effect between the protrusion and the groove.

[0020] In one optional embodiment, a gap is left between the protrusion and the groove, and in the width direction of the plastic part, the gap g between the protrusion and the groove satisfies 0.05mm < g ≤ 2mm.

[0021] Beneficial effects: By limiting the gap between the protrusion and the groove, it is easier to install the protrusion and the groove smoothly. If the gap is too small, it will be difficult to assemble the protrusion and the groove. If the gap is too large, the first plate and the second plate will easily wobble.

[0022] In one alternative embodiment, in the height direction of the plastic part, the inner side surface of the first step is coplanar with the inner side surface of the second step.

[0023] And / or, in the height direction of the plastic part, the inner side of the protrusion is not higher than the inner side of the first step or the inner side of the second step.

[0024] Beneficial effects: The inner surface of the first step is the lowest surface of the first plate, and the inner surface of the second step is the lowest surface of the second plate. By limiting the inner surfaces of the first and second steps to be coplanar, it can be ensured that the first and second plates are at the same height, thus facilitating the installation of the electrode post. By limiting the inner surface of the protrusion to not be higher than the inner surface of the first or second step, it can be prevented that the inner surface of the protrusion squeezes the electrode assembly.

[0025] Secondly, this utility model also provides a battery cell, comprising:

[0026] The casing has an opening on one side and an electrode assembly inside;

[0027] A cover plate is placed over the opening;

[0028] The aforementioned plastic component is disposed between the cover plate and the electrode assembly.

[0029] Beneficial effects: Because the battery pack includes plastic components, it has the same effect as plastic components, namely, using the snap-fit ​​protrusion of the first plate and the snap-fit ​​through hole of the second plate to achieve limiting support, which can effectively support the first and second plates, improve their stability, prevent excessive sag, and prevent the first and second plates from shaking inside the battery cell, causing damage to the battery cell, thereby improving the production yield of the battery cell. Moreover, the first plate is provided with a first step away from the cover plate, and the snap-fit ​​protrusion is located on the outer side of the first step. The second plate is provided with a second step away from the cover plate, and the snap-fit ​​through hole is located on the second step. This ensures that the snap-fit ​​protrusion is located between the plastic component and the cover plate, preventing the snap-fit ​​protrusion from interfering with the cover plate or the electrode assembly of the battery cell.

[0030] Thirdly, the present invention also provides a battery pack, comprising: at least one of the above-mentioned battery cells.

[0031] Beneficial effects: The battery pack of this utility model utilizes the snap-fit ​​protrusion of the first plate and the snap-fit ​​through hole of the second plate to achieve limiting support. This effectively supports the first and second plates, improves their stability, prevents excessive sag, and avoids the first and second plates from shaking inside the battery cell, which could damage the cell and thus improve the production yield of the battery cell. Furthermore, the first plate has a first step away from the cover plate, and the snap-fit ​​protrusion is located on the outer side of the first step. The second plate has a second step away from the cover plate, and the snap-fit ​​through hole is located on the second step. This ensures that the snap-fit ​​protrusion is located between the plastic part and the cover plate, preventing the snap-fit ​​protrusion from interfering with the cover plate or the electrode assembly of the battery cell. Attached Figure Description

[0032] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of a plastic part and a cover plate in accordance with an embodiment of the present utility model;

[0034] Figure 2 for Figure 1 Sectional view at point AA;

[0035] Figure 3This is a front view of the first plate of a plastic part according to an embodiment of the present utility model;

[0036] Figure 4 This is a bottom view of the first plate of a plastic part according to an embodiment of the present utility model;

[0037] Figure 5 This is a side view of the first plate of a plastic part according to an embodiment of the present utility model;

[0038] Figure 6 This is a front view of the second plate of a plastic part according to an embodiment of the present utility model;

[0039] Figure 7 This is a side view of the second plate of a plastic part according to an embodiment of the present utility model.

[0040] Explanation of reference numerals in the attached figures:

[0041] 1. First plate; 2. Second plate; 3. First step; 4. Snap-fit ​​protrusion; 5. Second step; 6. Snap-fit ​​through hole; 7. Protrusion; 8. Groove; 9. Cover plate; 10. Explosion-proof valve; 11. Vent hole. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0043] The following is combined Figures 1 to 7 The following describes embodiments of the present invention.

[0044] According to embodiments of the present invention, on the one hand, such as Figure 1 and Figure 2 As shown, a plastic part is provided, mainly including: a first plate 1 and a second plate 2 connected to each other. The first plate 1 is provided with an inward first step 3 on the side near the second plate 2. The outer side of the first step 3 is provided with at least one snap-fit ​​protrusion 4. The second plate 2 is provided with an inward second step 5 on the side near the first plate 1. The second step 5 is provided with a snap-fit ​​through hole 6 corresponding to the snap-fit ​​protrusion 4. The snap-fit ​​protrusion 4 snaps into the snap-fit ​​through hole 6.

[0045] The plastic part provided in this embodiment of the utility model utilizes the snap-fit ​​protrusion 4 of the first plate 1 and the snap-fit ​​through hole 6 of the second plate 2 to achieve limiting support. This effectively supports the first plate 1 and the second plate 2, improves their stability, prevents excessive sag, and avoids the first plate 1 and the second plate 2 from shaking inside the battery cell, which could damage the battery cell, thereby improving the production yield of the battery cell. Moreover, the first plate 1 is provided with a first step 3 away from the cover plate 9, and the snap-fit ​​protrusion 4 is provided on the outer side of the first step 3. The second plate 2 is provided with a second step 5 away from the cover plate 9, and the snap-fit ​​through hole 6 is provided on the second step 5. This ensures that the snap-fit ​​protrusion 4 is located between the plastic part and the cover plate 9, preventing the snap-fit ​​protrusion 4 from interfering with the cover plate 9 or the electrode assembly of the battery cell.

[0046] Specifically, the "inner" and "outer" directions in this embodiment of the utility model are as follows: Figure 2 As shown. The snap-fit ​​protrusions 4 can be set one-to-one with the snap-fit ​​through holes 6. The plastic parts are located inside the cover plate 9 of the battery cell.

[0047] It should be noted that the present invention does not limit the number of snap-fit ​​protrusions 4 and snap-fit ​​through holes 6, and one, two or more can be selected as needed.

[0048] like Figure 2 As shown, an explosion-proof valve 10 is also provided on the cover plate 9. Figure 6 As shown, the plastic part is provided with multiple vent holes 11 corresponding to the explosion-proof valve 10.

[0049] In one embodiment, such as Figure 2 As shown, the snap-fit ​​protrusion 4 and the snap-fit ​​through hole 6 are located on the inner side of the explosion-proof valve 10. On the one hand, the explosion-proof valve 10 is generally located in the middle of the length direction of the cover plate 9, which can balance the lengths of the first plate 1 and the second plate 2, preventing one from being too long and affecting the support effect. On the other hand, the explosion-proof valve 10 needs to be provided with an exhaust channel. In this embodiment of the utility model, the snap-fit ​​protrusion 4 and the snap-fit ​​through hole 6 are installed using the space of the exhaust channel, eliminating the need to leave additional installation space for the first step 3 and the second step 5, thereby improving the space utilization rate of the battery cell.

[0050] To improve the fixing effect between the snap-fit ​​protrusion 4 and the snap-fit ​​through hole 6, in one embodiment, the end of the snap-fit ​​protrusion 4 is also provided with a barb.

[0051] In one embodiment, such as Figures 3 to 5 As shown, the first step 3 extends toward the second plate 2 to form a protrusion 7, and the snap-fit ​​protrusion 4 is provided on the protrusion 7.

[0052] Furthermore, such as Figure 6 As shown, the second step 5 has a groove 8 corresponding to the protrusion 7, and the snap-fit ​​through hole 6 is provided on the groove 8.

[0053] By setting a protrusion 7 on the first step 3 and a groove 8 on the second step 5, and setting a snap-fit ​​protrusion 4 on the protrusion 7 and a snap-fit ​​through hole 6 on the groove 8, the protrusion 7 and the groove 8 are used to achieve primary limiting support, and the snap-fit ​​protrusion 4 and the snap-fit ​​through hole 6 are used to achieve secondary limiting support. This can further improve the stability of the first plate 1 and the second plate 2, improve the production yield of the battery cell, and also help reduce manufacturing costs.

[0054] It should be noted that the number of protrusions 7 and grooves 8 in this embodiment of the invention is not limited, and one, two or more can be selected as needed. In addition, the protrusions 7 can be provided in a one-to-one correspondence with the snap-fit ​​protrusions 4, and the grooves 8 can be provided in a one-to-one correspondence with the snap-fit ​​through holes 6.

[0055] Furthermore, in one embodiment, such as Figure 2 and Figure 4 As shown, in the height direction of the plastic part, the thickness H1 of the protrusion 7, the height H2 of the snap-fit ​​protrusion 4, and the thickness H3 of the plastic part satisfy H1 + H2 < H3. Specifically, the height direction of the plastic part is also the inward and outward direction.

[0056] By limiting the thickness H1 of the protrusion 7 and the height H2 of the snap-fit ​​protrusion 4 to be less than the thickness H3 of the plastic part, it is ensured that the height of the snap-fit ​​protrusion 4 does not exceed the outer side of the plastic part, thus preventing the snap-fit ​​protrusion 4 from affecting the installation of the plastic part and the cover plate 9. The outer sides of the first step 3 and the second step 5 generally correspond to the explosion-proof valve 10 on the cover plate 9. Limiting the thickness H1 of the protrusion 7 and the height H2 of the snap-fit ​​protrusion 4 to be less than the thickness H3 of the plastic part can also prevent the snap-fit ​​protrusion 4 from interfering with the explosion-proof valve 10, thereby improving the safety of the battery cell.

[0057] Furthermore, in one embodiment, the thickness H1 of the protrusion 7 satisfies 0.5mm ≤ H1 ≤ 2.5mm. For example, the thickness H1 of the protrusion 7 is 0.5mm, 1mm, 2mm, 2.5mm, etc. By limiting the thickness of the protrusion 7, it is possible to ensure effective engagement between the protrusion 7 and the groove 8, as well as effective installation of the plastic part and the cover plate 9. If the thickness H1 of the protrusion 7 is greater than 2.5mm, the engagement protrusion 4 is likely to be too high, thus interfering with the cover plate 9, especially with the explosion-proof valve 10 on the cover plate 9. If the thickness H1 of the protrusion 7 is less than 0.5mm, the limiting ability is insufficient, affecting the engagement effect between the protrusion 7 and the groove 8.

[0058] And / or, the height H2 of the snap-fit ​​protrusion 4 satisfies 1mm ≤ H2 ≤ 8mm. For example, the height H2 of the snap-fit ​​protrusion 4 can be 1mm, 3mm, 5mm, 8mm, etc. Similarly, by limiting the thickness of the snap-fit ​​protrusion 4, it is possible to ensure that the snap-fit ​​protrusion 4 and the snap-fit ​​through hole 6 are effectively snapped together and that the plastic part is effectively installed on the cover plate 9. If the height H2 of the snap-fit ​​protrusion 4 is greater than 8mm, the snap-fit ​​protrusion 4 is likely to be too high, thus interfering with the cover plate 9, especially with the explosion-proof valve 10 on the cover plate 9. If the height H2 of the snap-fit ​​protrusion 4 is less than 1mm, the limiting ability is insufficient, affecting the snap-fit ​​effect between the snap-fit ​​protrusion 4 and the snap-fit ​​through hole 6.

[0059] In one embodiment, such as Figure 3 As shown, in the length direction of the plastic part, the dimension L1 of the protrusion 7 satisfies 5mm≤L1≤20mm. For example, the dimension L1 of the protrusion 7 is 5mm, 10mm, 15mm, 20mm, etc.

[0060] And / or, in the width direction of the plastic part, the dimension L2 of the protrusion 7 satisfies 3mm≤L2≤25mm. For example, the dimension L2 of the protrusion 7 is 3mm, 10mm, 15mm, 25mm, etc.

[0061] By limiting the length and / or width of the protrusion 7, the effective engagement between the protrusion 7 and the groove 8 can be further ensured. If the length and / or width of the protrusion 7 is too large, it is easy to deform and shrink during the injection molding process. If the protrusion 7 is too thin, the limiting ability is insufficient, which affects the engagement effect between the protrusion 7 and the groove 8.

[0062] Specifically, the length direction of the plastic part is as follows: Figure 1 As indicated by arrow L in the diagram.

[0063] In one embodiment, such as Figure 7 As shown, in the height direction of the plastic part, the thickness H4 of the groove 8 satisfies 0.6mm ≤ H4 ≤ 2.5mm. For example, the thickness H4 of the groove 8 can be 0.6mm, 1mm, 2mm, 2.5mm, etc. By limiting the thickness of the groove 8, it is possible to ensure the effective engagement between the protrusion 7 and the groove 8, as well as the effective installation of the plastic part and the cover plate 9. If the thickness H4 of the groove 8 is greater than 2.5mm, it is easy to deform and shrink during injection molding. If the thickness H4 of the groove 8 is less than 0.6mm, the limiting ability is insufficient, affecting the engagement effect between the protrusion 7 and the groove 8.

[0064] In one embodiment, such as Figure 1As shown, a gap is left between the protrusion 7 and the recess 8. In the width direction of the plastic part, the gap g between the protrusion 7 and the recess 8 satisfies 0.05mm < g ≤ 2mm. For example, the gap g between the protrusion 7 and the recess 8 can be 0.05mm, 0.5mm, 1mm, 2mm, etc. By limiting the gap between the protrusion 7 and the recess 8, it is easier to install the protrusion 7 and the recess 8 smoothly. If the gap g is less than 0.05mm, it will be difficult to assemble the protrusion 7 and the recess 8; if the gap g is greater than 2mm, the first plate 1 and the second plate 2 will easily wobble.

[0065] Specifically, the width direction of the plastic part is as follows: Figure 1 As indicated by the arrow W in the diagram.

[0066] In one embodiment, in the height direction of the plastic part, the inner surface of the first step 3 is coplanar with the inner surface of the second step 5. The inner surface of the first step 3 is as follows: Figure 1 As shown in M1, the inner surface of the second step 5 is as follows: Figure 1 As shown in M2.

[0067] And / or, in the height direction of the plastic part, the inner surface of the protrusion 7 is not higher than the inner surface of the first step 3 or the inner surface of the second step 5. The inner surface of the protrusion 7 is as follows: Figure 1 As shown in N in the diagram.

[0068] The inner surface of the first step 3 is the lowest surface of the first plate 1, and the inner surface of the second step 5 is the lowest surface of the second plate 2. By limiting the inner surface of the first step 3 and the inner surface of the second step 5 to be coplanar, it can be ensured that the first plate 1 and the second plate 2 are at the same height, thereby facilitating the installation of the pole post. By limiting the inner surface of the protrusion 7 to not be higher than the inner surface of the first step 3 or the inner surface of the second step 5, it can be prevented that the inner surface of the protrusion 7 squeezes the pole assembly.

[0069] According to an embodiment of this utility model, another aspect provides a battery cell, mainly comprising: a housing, a cover plate 9, and a plastic component. An opening is provided on one side of the housing, and an electrode assembly is disposed inside. The cover plate 9 covers the opening. The plastic component is disposed between the cover plate 9 and the electrode assembly.

[0070] Because the battery pack includes plastic parts, it has the same effect as plastic parts, namely, using the snap-fit ​​protrusion 4 of the first plate 1 and the snap-fit ​​through hole 6 of the second plate 2 to achieve limiting support, which can effectively support the first plate 1 and the second plate 2, improve their stability, prevent excessive sag, and prevent the first plate 1 and the second plate 2 from shaking inside the battery cell, causing damage to the battery cell, thereby improving the production yield of the battery cell. Moreover, the first plate 1 is provided with a first step 3 away from the cover plate 9, and the snap-fit ​​protrusion 4 is provided on the outer side of the first step 3. The second plate 2 is provided with a second step 5 away from the cover plate 9, and the snap-fit ​​through hole 6 is provided on the second step 5. This ensures that the snap-fit ​​protrusion 4 is located between the plastic parts and the cover plate 9, avoiding interference of the snap-fit ​​protrusion 4 with the cover plate 9 or the electrode group of the battery cell.

[0071] Specifically, a positive terminal and a negative terminal are spaced apart on the side of the electrode assembly facing the cover plate 9. The first plate 1 has a first mounting hole for the positive terminal, which also passes through the first mounting hole and connects to the cover plate 9. The second plate 2 has a second mounting hole for the negative terminal, which also passes through the second mounting hole and connects to the cover plate 9. One end of the first plate 1 with a locking protrusion 4 is away from the positive terminal, thus forming a two-end support structure for the positive terminal and the locking protrusion 4. Similarly, one end of the second plate 2 with a locking through hole 6 is away from the negative terminal, thus forming a two-end support structure for the negative terminal and the locking through hole 6.

[0072] Of course, in some other embodiments, the positive terminal can also be connected to the second plate 2, and the corresponding negative terminal is connected to the first plate 1.

[0073] According to an embodiment of the present invention, in another aspect, a battery pack is also provided, comprising: at least one battery cell.

[0074] The battery pack provided in this embodiment utilizes the snap-fit ​​protrusion 4 of the first plate 1 and the snap-fit ​​through hole 6 of the second plate 2 to achieve limiting support. This effectively supports the first plate 1 and the second plate 2, improving their stability and preventing excessive sag. It also prevents the first plate 1 and the second plate 2 from shaking inside the battery cell, which could damage the cell and thus improve the production yield. Furthermore, the first plate 1 has a first step 3 away from the cover plate 9, and the snap-fit ​​protrusion 4 is located on the outer side of the first step 3. The second plate 2 has a second step 5 away from the cover plate 9, and the snap-fit ​​through hole 6 is located on the second step 5. This ensures that the snap-fit ​​protrusion 4 is located between the plastic part and the cover plate 9, preventing the snap-fit ​​protrusion 4 from interfering with the cover plate 9 or the electrode assembly of the battery cell.

[0075] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A plastic part, characterized in that, include: A first plate and a second plate are connected. The first plate has an inward first step on the side near the second plate. The outer side of the first step has at least one snap-fit ​​protrusion. The second plate has an inward second step on the side near the first plate. The second step has a snap-fit ​​through hole corresponding to the snap-fit ​​protrusion. The snap-fit ​​protrusion snaps into the snap-fit ​​through hole.

2. The plastic part according to claim 1, characterized in that, The first step extends toward the second plate to form a protrusion, and the snap-fit ​​protrusion is provided on the protrusion; The second step has a groove corresponding to the protrusion, and the snap-fit ​​hole is provided on the groove.

3. The plastic part according to claim 2, characterized in that, In the height direction of the plastic part, the thickness H1 of the protrusion, the height H2 of the snap-fit ​​protrusion, and the thickness H3 of the plastic part satisfy H1+H2<H3.

4. The plastic part according to claim 3, characterized in that, The thickness H1 of the protrusion satisfies 0.5mm ≤ H1 ≤ 2.5mm; And / or, the height H2 of the snap-fit ​​protrusion satisfies 1mm≤H2≤8mm.

5. The plastic part according to claim 2, characterized in that, Along the length of the plastic part, the dimension L1 of the protrusion satisfies 5mm≤L1≤20mm; And / or, in the width direction of the plastic part, the dimension L2 of the protrusion satisfies 3mm≤L2≤25mm.

6. The plastic part according to claim 2, characterized in that, In the height direction of the plastic part, the thickness H4 of the groove portion satisfies 0.6mm≤H4≤2.5mm.

7. The plastic part according to claim 6, characterized in that, A gap is left between the protrusion and the groove. In the width direction of the plastic part, the gap g between the protrusion and the groove satisfies 0.05mm < g ≤ 2mm.

8. The plastic part according to any one of claims 2 to 7, characterized in that, In the height direction of the plastic part, the inner side surface of the first step is coplanar with the inner side surface of the second step; And / or, in the height direction of the plastic part, the inner side of the protrusion is not higher than the inner side of the first step or the inner side of the second step.

9. A battery cell, characterized in that, include: The casing has an opening on one side and an electrode assembly inside; A cover plate is placed over the opening; The plastic part according to any one of claims 1 to 8, wherein the plastic part is disposed between the cover plate and the electrode assembly.

10. A battery pack, characterized in that, include: At least one battery cell as described in claim 9.

Images