Lower plastic, cover plate assembly and battery

Abstract

The application relates to the technical field of power batteries, and provides a lower plastic, a cover plate assembly and a battery. The lower plastic comprises a body and a folding part capable of being folded relative to the body. A protrusion is arranged on the body, and a containing groove is formed on the other side corresponding to the protrusion. A supporting table is arranged on the folding part, and a sunken table corresponding to the containing groove is formed on the folding part, and the supporting table and the sunken table both protrude to the first side of the thickness direction of the folding part. According to the lower plastic, the sunken table of the folding part can abut against the pole lug, the pole lug is stably kept in the containing groove, the pole lug is prevented from being damaged due to random shaking in the shell, and the abutment between the folding part and the pole group is facilitated to realize, after the folding part is folded, the supporting table can abut against the body to constitute the position constraint of the folding part, the fixing effect on the pole group is improved, the risk of short circuit of the battery is reduced, and the safety performance of the battery is improved.

Description

Technical Field

[0001] This application relates to the field of power battery technology, and in particular to a lower plastic, cover plate assembly and battery. Background Technology

[0002] Generally, a battery consists of a casing, a cover, and an electrode assembly housed within the casing. The cover has terminals for electrically welding to the tabs on the electrode assembly. Currently, after the tabs are welded to the electrode assembly, they are usually loosely positioned between the electrode assembly and the cover. When the battery is subjected to vibration or impact, the electrode assembly is prone to shaking, and the tabs are easily torn or damaged by the external force. This can also lead to the tabs being inserted backwards into the electrode assembly, causing a short circuit within the electrode assembly and posing a safety hazard. Utility Model Content

[0003] In view of this, this application aims to provide a plastic substrate to improve the safety performance of batteries.

[0004] To achieve the above objectives, the technical solution of this application is implemented as follows: A plastic material suitable for placement on a battery cover includes a body conforming to the cover and a folding portion foldable relative to the body. The body has a protrusion that protrudes to one side in the thickness direction of the lower plastic. The protrusion is formed by the lower plastic itself and a receiving groove for accommodating the tab is formed on the lower plastic. The folded portion is provided with a support platform and a recessed platform formed on the folded portion corresponding to the receiving groove. Both the support platform and the recessed platform protrude toward a first side in the thickness direction of the folded portion, and the folded portion after folding can abut against the tab through the recessed platform and abut against the body through the support platform.

[0005] Furthermore, at least one side of the body in the width direction is provided with a support protrusion, the support protrusion being in the opposite direction to the protrusion of the main body; the support protrusion is flush with the second side in the thickness direction of the folded portion after folding, and both are used to abut against the electrode assembly of the battery.

[0006] Furthermore, the folding portions are two located at both ends of the body along its length, and each end of the body along its length is provided with a support protrusion; each folding portion is provided with a notch for avoiding the support protrusion at the corresponding end.

[0007] Furthermore, the folding portion is integrally formed with the body, and a glue-reducing groove is provided at the connection between the folding portion and the body.

[0008] Furthermore, the end of the folded portion connected to the main body is provided with a notch, which extends along the width direction of the main body; and / or, corresponding to the recessed platform, a recessed groove is formed on the second side of the folded portion in the thickness direction, and a plurality of reinforcing ribs are provided in the recessed groove.

[0009] Compared with related technologies, this application has the following advantages: (1) The lower plastic described in this application, through the setting of the receiving groove on the main body, provides a receiving space for the tab. Through the setting of the folding part, the countersunk platform of the folding part can abut against the tab, and stably hold the tab in the receiving groove, thereby constraining the tab to prevent it from shaking and being damaged in the shell. Moreover, it can also reduce the gap between the lower plastic and the electrode assembly, which is conducive to the abutment between the folding part and the electrode assembly, and helps to improve the fixing effect of the electrode assembly. At the same time, after the folding part is folded, the support platform can abut against the main body to form a positional constraint on the folding part, which is conducive to ensuring the fixing effect of the folding part on the electrode assembly, thereby effectively reducing the shaking of the electrode assembly, thereby reducing the risk of short circuit of the battery and improving the safety performance of the battery.

[0010] (2) By setting the support protrusion, the support protrusion can be flush with the folded part after folding and together abut against the end of the electrode group facing the cover plate, thus forming a support for the electrode group and ensuring that the electrode group is evenly stressed. This can improve the fixing effect of the electrode group in the housing, prevent the electrode group from shaking in the housing, thereby reducing the risk of electrode tab tearing or short circuit caused by electrode group shaking, and further improving the safety performance of the battery.

[0011] (3) By configuring the folding parts as two separate parts located at both ends of the main body, the two folding parts can match the setting positions of the positive and negative terminals of the battery, thereby protecting and fixing the positive and negative terminals of the electrode assembly. At the same time, the notch setting allows the folding parts to avoid the support protrusion, preventing interference between the support protrusion and the folding parts, thus ensuring that the folding parts can be folded into place.

[0012] (4) By setting the glue reduction groove, the material thickness at the connection between the folding part and the body can be reduced, making the folding part easier to fold relative to the body. This ensures the connection effect between the folding part and the body while facilitating the assembly operation of the cover plate assembly.

[0013] (5) By setting the notch, the width of the connection between the folding part and the main body can be reduced, further reducing the resistance of the folding part, making it easier for the folding part to fold relative to the main body, thereby further facilitating the assembly operation of the cover plate assembly. In addition, the setting of the groove and the reinforcing rib can reduce the amount of material used in the folding part while ensuring the structural strength of the recessed platform, which is conducive to the lightweight design of the lower plastic. Furthermore, the reinforcing rib can strengthen the recessed platform while ensuring the contact effect between the folding part and the electrode assembly.

[0014] Another object of this application is to provide a cover plate assembly comprising a cover plate, a lower plastic disposed on the cover plate as described above, and an electrode post passing through the lower plastic and the cover plate.

[0015] Furthermore, corresponding to the protrusion, the cover plate is formed with a boss protruding to a first side in the thickness direction, and a clearance groove is formed on the cover plate, with the protrusion located in the clearance groove; the pole post is spaced apart from the boss, and the pole post has a protruding section protruding to a first side in the thickness direction of the cover plate, and on the first side in the thickness direction of the cover plate, the protrusion height of the boss is greater than the protrusion height of the protruding section.

[0016] Furthermore, the cover plate assembly includes a connecting piece disposed on the side of the lower plastic away from the cover plate; the connecting piece has a first portion connected to the pole post and a second portion for connecting to the pole lug, the second portion being embedded in the receiving groove; the folded portion abuts against the first portion after being folded, and the recessed platform abuts against the second portion through the pole lug.

[0017] Furthermore, the bosses are a plurality of those spaced apart on the cover plate, and the protrusions are arranged one-to-one with the bosses; one of the bosses is provided with an injection hole, and corresponding to the injection hole, another protrusion is provided with an outlet hole; and / or, the cover plate is provided with an explosion-proof valve mounting hole, and at least one of the bosses is provided between the explosion-proof valve mounting hole and the pole post, and corresponding to the explosion-proof valve mounting hole, and the lower plastic is provided with a vent hole.

[0018] Compared with related technologies, this application has the following advantages: (1) The cover plate described in this application can fix the electrode assembly itself and the electrode tabs of the electrode assembly by the above-mentioned lower plastic setting. When the battery is subjected to external force impact, it can prevent the electrode tabs from being torn or inserted into the electrode assembly due to external force, and reduce the shaking of the electrode assembly in the casing, thereby reducing the risk of short circuit of the battery and improving the safety performance of the battery.

[0019] (2) The clearance groove on the cover plate provides a space for the protrusion on the lower plastic. At the same time, the protrusion height of the boss corresponding to the clearance groove is greater than the protrusion height of the pole post. When the cover plate is subjected to external force, the boss can withstand the impact, so as to avoid the pole post being directly subjected to external force and causing damage to the tab and pole group, thereby improving the installation performance of the battery.

[0020] (3) By setting the connecting piece, a stable electrical connection between the pole and the tab can be achieved. At the same time, the tab connecting part of the connecting piece is embedded in the receiving groove, which not only limits the connection of the connecting piece and facilitates the connection between it and the pole, but also facilitates the connection between the connecting piece and the tab. Meanwhile, the second part and the sinker can form a clamping and fixing of the tab, so as to further improve the fixing effect of the tab.

[0021] (4) By placing the boss between the explosion-proof valve mounting hole and the terminal post, the hot gas discharged from the explosion-proof valve can be prevented from affecting the terminal post, thus achieving the function of thermoelectric separation and improving battery safety performance. At the same time, placing the liquid injection hole on the boss can effectively reduce the weakening of the cover plate structure strength caused by the liquid injection hole.

[0022] Another object of this application is to provide a battery having a cover assembly as described above.

[0023] The battery of this application and / or the aforementioned cover plate assembly and lower plastic have the same technical effects as related technologies, and will not be described in detail here. Attached Figure Description

[0024] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the cover plate assembly described in an embodiment of this application; Figure 2 This is a structural schematic diagram from another perspective of the cover plate assembly described in the embodiments of this application when no connecting piece is provided; Figure 3 This is a schematic diagram of the structure of the lower plastic facing the electrode assembly as described in the embodiments of this application; Figure 4 for Figure 1 Enlarged view of point A in the middle; Figure 5 for Figure 1 Enlarged view of point B in the middle; Figure 6 for Figure 2 Enlarged view of point C in the middle; Figure 7 This is a schematic diagram of the structure of the cover plate assembly connected to the pole group according to an embodiment of this application; Figure 8 for Figure 7 Enlarged view of point D in the middle; Figure 9 This is a schematic diagram showing the connection between the cover plate assembly and the electrode group after the folding portion is folded, as described in the embodiments of this application. Figure 10 This is a top view showing the connection between the cover plate assembly and the pole group after the folding portion of the folding portion is folded up, as described in the embodiments of this application. Figure 11 for Figure 9 A cross-sectional view at the location shown in EE; Figure 12 for Figure 11 Enlarged view at point F; Figure 13 This is a schematic diagram of the battery structure described in an embodiment of this application; Figure 14 for Figure 13 A cross-sectional view at the location shown in GG; Explanation of reference numerals in the attached figures: 1. Lower plastic; 101. Body; 1011. Receiving groove; 1012. Support protrusion; 1013. Liquid outlet; 1014. Groove; 1015. Vent hole; 1016. Through hole; 1017. Connecting rib; 102. Folded section; 1021. Support platform; 1022. Recessed platform; 1023. Notch; 1024. Slot; 1025. Reinforcing rib; 103. Glue Reduction Tank; 104. Gap; 2. Cover plate; 201. Pole post; 202. Boss; 2021. Injection hole; 2022. Clearance groove; 203. Explosion-proof valve mounting hole; 3. Electrode assembly; 301. Electrode tab; 4. Connecting piece; 401. First part; 402. Second part; 403. Clearance part; 5. Shell. Detailed Implementation

[0025] To make the technical solution and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0027] Furthermore, it should be noted that in the description of this application, if terms such as "upper," "lower," "inner," or "outer" appear, indicating orientation or positional relationship, these are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this application and 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, and therefore should not be construed as a limitation on this application. In addition, if terms such as "first" or "second" appear, they are also used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] Furthermore, in the description of this application, unless otherwise expressly defined, the terms "installation," "connection," "joining," and "connector" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application in light of the specific circumstances.

[0029] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0030] The present application will now be described in detail through exemplary embodiments. However, it should be understood that, without further description, elements, structures, and features in one embodiment may be advantageously incorporated into other embodiments.

[0031] An embodiment of the first aspect of this application provides a lower plastic 1.

[0032] In related technologies, the tab 301 is usually loosely disposed between the electrode assembly 3 and the cover plate 2. When the battery is under vibration or subjected to external impact, the electrode assembly 3 is prone to shaking, and the tab 301 is easily torn and damaged by external force. This can also cause the tab 301 to be inserted backward into the electrode assembly 3, resulting in a short circuit inside the electrode assembly 3, which poses a safety hazard.

[0033] In view of this, in order to overcome the shortcomings of the related technology, in the lower plastic 1 of this embodiment, combined with Figures 1 to 3 ,as well as Figure 11As shown, the overall design includes a body 101 that conforms to the shape of the cover plate 2, and a folding portion 102 that can be folded relative to the body 101.

[0034] The main body 101 has a protrusion protruding from one side in the thickness direction of the lower plastic 1. The protrusion is formed by the lower plastic 1 itself, and a receiving groove 1011 for accommodating the tab 301 is formed on the lower plastic 1. The folded portion 102 has a support platform 1021 and a recessed platform 1022 formed on the folded portion 102 corresponding to the receiving groove 1011. Both the support platform 1021 and the recessed platform 1022 protrude from the first side in the thickness direction of the folded portion 102. The folded portion 102 can abut against the tab 301 through the recessed platform 1022 and abut against the main body 101 through the support platform 1021.

[0035] Therefore, the receiving groove 1011 on the main body 101 provides a receiving space for the tab 301. The folding portion 102's recessed platform 1022 abuts against the tab 301, stably holding it within the receiving groove 1011. This constitutes a limiting constraint on the tab 301, preventing it from swinging freely within the housing 5 and causing damage. Furthermore, it reduces the gap between the lower plastic 1 and the electrode assembly 3, facilitating contact between the folding portion 102 and the electrode assembly 3, thus improving the fixing effect on the electrode assembly 3. Simultaneously, after the folding portion 102 is folded, the support platform 1021 abuts against the main body 101, constraining the position of the folding portion 102. This helps ensure the fixing effect of the folding portion 102 on the electrode assembly 3, effectively reducing the shaking of the electrode assembly 3. This reduces the risk of short circuits in the battery and improves battery safety.

[0036] Based on the above overview, specifically, in related technologies, the tab 301 is located between the lower plastic 1 and the electrode assembly 3 of the cover plate 2, requiring a certain space to be reserved between the lower plastic 1 and the electrode assembly 3 for arranging the tab 301. However, in this embodiment, by providing a receiving groove 1011 on the lower plastic 1 to provide receiving space for the tab 301, the tab 301 can be prevented from occupying the space between the lower plastic 1 and the electrode assembly 3, thereby improving the space utilization rate inside the battery casing 5 and contributing to an increase in battery capacity.

[0037] In addition, the support platform 1021 is configured as two separate units located on both sides of the folded portion 102 in the width direction.

[0038] Combination Figure 2 , Figure 3As shown, in some exemplary embodiments, at least one side of the body 101 in the width direction is provided with a support protrusion 1012, the support protrusion 1012 being opposite in protrusion direction to the protrusion of the protrusion. The support protrusion 1012 is flush with the second side in the thickness direction of the folded portion 102 after folding, and both are used to abut against the electrode group 3 of the battery.

[0039] By setting the support protrusion 1012, the support protrusion 1012 can be flush with the folded part 102 after folding, and together they abut against the end of the electrode assembly 3 facing the cover plate 2, forming a support for the electrode assembly 3 and ensuring that the electrode assembly 3 is evenly stressed. This can improve the fixing effect of the electrode assembly 3 in the housing 5, prevent the electrode assembly 3 from shaking in the housing 5, thereby reducing the risk of the tab 301 tearing or short circuit caused by the shaking of the electrode assembly 3, and further improving the safety performance of the battery.

[0040] Furthermore, in some exemplary embodiments, there are two folding portions 102 located at both ends of the body 101 along its length, and each end of the body 101 along its length is provided with a support protrusion 1012. Each folding portion 102 is provided with a notch 1023 for avoiding the corresponding end support protrusion 1012.

[0041] By configuring two folding portions 102 at both ends of the main body 101, the two folding portions 102 can be matched with the setting positions of the positive and negative terminals of the battery, thereby protecting and fixing the positive and negative terminal tabs 301 of the electrode assembly 3. At the same time, the notch 1023 allows the folding portion 102 to avoid the support protrusion 1012, preventing interference between the support protrusion 1012 and the folding portion 102, and ensuring that the folding portion 102 can be folded into place.

[0042] In practical implementation, the support protrusions 1012 are respectively located on both sides of the width direction of the flipped portion, and the folded portion 102 has notches 1023 on both sides of the support protrusions 1012. When the support protrusions 1012 are inserted into the notches 1023, they can form a limiting constraint on the folded portion 102 to prevent the support protrusions 1012 from moving along the width direction, thereby ensuring the stability of the position of the folded portion 102 and ensuring the fixing effect of the folded portion 102 on the tab 301.

[0043] In addition, the support protrusion 1012 in this embodiment also includes two protrusions located on both sides of the vent hole 1015 described below along the width direction, so that the middle of the lower plastic body 101 provides sufficient support for the pole group 3.

[0044] Combination Figure 5 , Figure 6 As shown, in some exemplary embodiments, the folding portion 102 is integrally formed with the body 101, and a glue-reducing groove 103 is provided at the connection between the folding portion 102 and the body 101.

[0045] By setting the adhesive reduction groove 103, the material thickness at the connection between the folding part 102 and the body 101 can be reduced, making it easier for the folding part 102 to fold relative to the body 101. This ensures the connection effect between the folding part 102 and the body 101 while facilitating the assembly operation of the cover plate assembly.

[0046] Meanwhile, in some exemplary embodiments, the end of the folded portion 102 connected to the body 101 is provided with a notch 104, which extends along the width direction of the body 101.

[0047] By setting the notch 104, the width of the connection between the folding part 102 and the body 101 can be reduced, further reducing the resistance of the folding part 102 to folding, making the folding part 102 easier to fold relative to the body 101, thereby further facilitating the assembly operation of the cover plate assembly.

[0048] Furthermore, combined Figure 1 , Figure 4 As shown, in some exemplary embodiments, corresponding to the settling platform 1022, a settling groove 1024 is formed on the second side of the folded portion 102 in the thickness direction, and a plurality of reinforcing ribs 1025 are provided in the settling groove 1024.

[0049] By setting the sink 1024 and the reinforcing rib 1025, the structural strength of the sink platform 1022 can be guaranteed while the amount of material used in the folded part 102 can be reduced, which is conducive to the lightweight design of the lower plastic 1. In addition, the reinforcing rib 1025 can strengthen the sink platform 1022 while ensuring the contact effect of the folded part 102 with the pole group 3.

[0050] In specific implementation, combined with Figure 9 , Figure 10 As shown, the sum of the areas S1 of the folded portion 102 abutting the electrode group 3, the sum of the areas S2 of the supporting protrusion 1012, and the sum of the areas S of the end face of the electrode group 3 abutting the lower plastic 1 satisfy the following: 30% ≤ (S1 + S2) / S ≤ 76%, 700mm2 ≤ S1 ≤ 7600mm2, 1000mm2 ≤ S2 ≤ 11200mm2, 5100mm2 ≤ S ≤ 24600mm2.

[0051] To verify the rationality of selecting the sum of the areas S1 of the folded portion 102 abutting the electrode group 3, the sum of the areas S2 of the supporting protrusion 1012, and the sum of the areas S of the end face of the electrode group 3 abutting the lower plastic 1 in this embodiment, the verification is shown in the table.

[0052] Table 1

[0053] As shown in Table 1, this embodiment ensures sufficient contact area between the electrode group 3 and the lower plastic 1 by combining the sum of the areas S1 of the folded portion 102 abutting against the electrode group 3, the sum of the areas S2 of the supporting protrusion 1012, and the sum of the end face areas S of the electrode group 3 abutting against the lower plastic 1. This ensures the fixing effect of the lower plastic 1 on the electrode group 3 and reduces the shaking of the electrode group 3 within the battery casing 5.

[0054] In this embodiment, the lower plastic 1 adopts the above design. Through the setting of the receiving groove 1011 on the main body 101, the receiving groove 1011 provides a receiving space for the electrode 301. Through the setting of the folding part 102, the recess 1022 of the folding part 102 can abut against the electrode 301, and stably hold the electrode 301 in the receiving groove 1011, thereby constraining the electrode 301 to prevent the electrode 301 from shaking and being damaged in the housing 5. Moreover, it can also reduce the gap between the lower plastic 1 and the electrode group 3, which is conducive to the abutment of the folding part 102 and the electrode group 3, and helps to improve the fixing effect of the electrode group 3. Meanwhile, after the folding portion 102 is folded, the support platform 1021 can abut against the main body 101 to form a positional constraint on the folding portion 102, which helps to ensure the fixing effect of the folding portion 102 on the electrode group 3, thereby effectively reducing the shaking of the electrode group 3. As a result, the risk of battery short circuit is reduced, the safety performance of the battery is improved, and it has good practicality.

[0055] An embodiment of the second aspect of this application provides a cover plate assembly, which, in its overall structure, combines... Figures 7 to 10 As shown, it includes a cover plate 2, a lower plastic 1 disposed on the cover plate 2 as described above, and an electrode post 201 passing through the lower plastic 1 and the cover plate 2.

[0056] Therefore, by setting the lower plastic 1 as described above, the electrode assembly 3 itself and the tabs 301 of the electrode assembly 3 can be fixed. When the battery is subjected to external impact, the tabs 301 can be prevented from being torn or inserted into the electrode assembly 3 due to external force, and the shaking of the electrode assembly 3 in the housing 5 can be reduced, thereby reducing the risk of short circuit of the battery and improving the safety performance of the battery.

[0057] Based on the above overall introduction, specifically, in this embodiment, both the cover plate 2 and the lower plastic 1 have a rectangular structure, and the pole posts 201 are respectively disposed at both ends of the cover plate 2 and the lower plastic 1 in the length direction, in order to adapt to the structure of the square battery cell and enable the pole posts 201 to connect to the positive and negative pole tabs 301 of the pole group 3.

[0058] In some of the exemplary implementations, combined with Figure 11 , Figure 12As shown, corresponding to the protrusion, a boss 202 protruding towards its own thickness direction is formed on the cover plate 2, and a relief groove 2022 is formed on the cover plate 2, with the protrusion located in the relief groove 2022. The pole post 201 is spaced apart from the boss 202, and the pole post 201 has a protruding section protruding towards the first side in the thickness direction of the cover plate 2. On the first side in the thickness direction of the cover plate 2, the protrusion height of the boss 202 is greater than the protrusion height of the protruding section.

[0059] The clearance groove 2022 on the cover plate 2 provides space for the protrusion on the lower plastic 1. At the same time, the protrusion height of the boss 202 corresponding to the clearance groove 2022 is greater than the protrusion height of the protruding end of the pole post 201. When the cover plate 2 is subjected to external force, the boss 202 can withstand the impact, so as to avoid the pole post 201 being directly subjected to external force and causing damage to the tab 301 and the electrode group 3, thereby improving the installation performance of the battery.

[0060] In specific implementation, the distance d between the top of the boss 202 and the top of the protruding section of the pole post 201 satisfies: 1.0mm≤d≤2.0mm. Specifically, the height difference d between the top of the boss 201 and the top of the pole post 3 is 1.0mm, 1.2mm, 1.5mm, 1.7mm or 2.0mm, etc., to ensure the protective effect of the boss 202 on the pole post 201.

[0061] In some exemplary embodiments, the cover assembly includes a connecting piece 4 disposed on the side of the lower plastic 1 away from the cover 2. The connecting piece 4 has a first portion 401 connected to the pole post 201 and a second portion 402 for connecting to the tab 301, the second portion 402 being embedded in a receiving groove 1011. The folded-over portion 102 abuts against the first portion 401, and the recess 1022 abuts against the second portion 402 via the tab 301.

[0062] By setting the connecting piece 4, a stable electrical connection can be achieved between the pole post 201 and the tab 301. Simultaneously, the connecting portion of the tab 301 of the connecting piece 4 is embedded in the receiving groove 1011, which not only limits the connection of the connecting piece 4, facilitating its connection with the pole post 201, but also facilitates the connection between the connecting piece 4 and the tab 301. Furthermore, the second part 402 and the countersunk platform 1022 can clamp and fix the tab 301, further improving the fixation effect of the tab 301.

[0063] In some exemplary embodiments, the bosses 202 are multiple and spaced apart on the cover plate 2, with each boss and protrusion corresponding to the other. One boss 202 has a liquid injection hole 2021, and another protrusion has a liquid outlet hole 1013. By placing the bosses 202 between the explosion-proof valve mounting hole 203 and the terminal post 201, the hot gas discharged from the explosion-proof valve can be prevented from affecting the terminal post 201, thus achieving thermoelectric separation and improving battery safety performance.

[0064] Furthermore, in some exemplary embodiments, the cover plate 2 is provided with an explosion-proof valve mounting hole 203, and at least one boss 202 is provided between the explosion-proof valve mounting hole 203 and the pole post 201. Corresponding to the explosion-proof valve mounting hole 203, a vent hole 1015 is provided on the lower plastic 1. By providing the injection hole 2021 on the boss 202, the weakening effect of the injection hole 2021 on the structural strength of the cover plate 2 can be effectively reduced.

[0065] In a specific implementation, the second part 402 of the connecting piece 4 in this embodiment is provided with a clearance part 403 for avoiding the liquid outlet hole 1013, and the connecting piece 4 in this embodiment can simultaneously connect the tabs 301 of two electrode groups 3.

[0066] In addition, in this embodiment, the lower plastic 1 is recessed into the side where the electrode assembly 3 is located, corresponding to the position of the explosion-proof valve mounting hole 203, to form a groove 1014, thereby providing sufficient installation space for the explosion-proof valve. Based on this, in this embodiment, the vent hole 1015 is provided at the bottom of the groove 1014.

[0067] Furthermore, the bottom of the aforementioned groove 1014 is provided with a plurality of spaced through holes 1016. These through holes 1016 are arranged in an elongated shape around the vent hole 1015, and a connecting rib 1017 is formed between two adjacent through holes 1016. This divides the bottom of the groove 1014 into two parts by the through holes 1016, and the two parts are connected only by the connecting rib 1017. Thus, when thermal runaway occurs in the electrode group 3 and a large amount of gas is rapidly generated inside the battery casing 5, the gas inside the casing 5 can push against the bottom of the groove 1014, and the high temperature of the gas can melt and break the connecting rib 1017, causing the part of the groove 1014 with the vent hole 1015 to fall off. This is equivalent to enlarging the diameter of the vent hole 1015, thereby facilitating the discharge of gas and preventing the battery from exploding.

[0068] It is worth noting that, for the cover plate assembly of this embodiment, based on the above exemplary implementations, in a specific implementation, as shown in the figure, it includes a cover plate 2, a lower plastic 1 disposed on the cover plate 2, and an pole post 201 passing through the lower plastic 1 and the cover plate 2.

[0069] The lower plastic 1 includes a body 101 conforming to the cover plate 2, and a folding portion 102 foldable relative to the body 101. The body 101 has a protrusion protruding to one side in the thickness direction of the lower plastic 1. The protrusion is formed by the lower plastic 1 itself, and a receiving groove 1011 for accommodating the tab 301 is formed on the lower plastic 1. The folding portion 102 has a support platform 1021 and a recessed platform 1022 formed on the folding portion 102 corresponding to the receiving groove 1011. Both the support platform 1021 and the recessed platform 1022 protrude to the first side in the thickness direction of the folding portion 102, and the folded portion 102 can abut against the tab 301 through the recessed platform 1022 and abut against the body 101 through the support platform 1021.

[0070] In addition, support protrusions 1012 are provided on both sides of the main body 101 in the width direction, and the protrusion direction of the support protrusions 1012 is opposite to that of the main body. The support protrusions 1012 are flush with the side of the folded portion 102 after folding, and are used to abut against the battery electrode group 3. There are two folded portions 102 at both ends of the main body 101 in the length direction, and support protrusions 1012 are provided at both ends of the main body 101 in the length direction. Each folded portion 102 is provided with a notch 1023 for avoiding the support protrusion 1012 at the corresponding end.

[0071] Furthermore, the folded portion 102 is integrally formed with the main body 101, and a reducing groove 103 is provided at the connection between the folded portion 102 and the main body 101. A notch 104 is provided at one end of the folded portion 102 connected to the main body 101, and the notch 104 extends along the width direction of the main body 101. Corresponding to the recessed platform 1022, a recessed groove 1024 is formed on the second side of the folded portion 102 in the thickness direction, and multiple reinforcing ribs 1025 are provided within the recessed groove 1024.

[0072] Furthermore, corresponding to the protrusion, a boss 202 protruding towards its own thickness direction is formed on the cover plate 2, and a relief groove 2022 is formed on the cover plate 2, with the protrusion located in the relief groove 2022. The pole post 201 is spaced apart from the boss 202, and the pole post 201 has a protruding section protruding towards the first side in the thickness direction of the cover plate 2. On the first side in the thickness direction of the cover plate 2, the protrusion height of the boss 202 is greater than the protrusion height of the protruding section.

[0073] Furthermore, the cover plate assembly includes a connecting piece 4 disposed on the side of the lower plastic 1 away from the cover plate 2. The connecting piece 4 has a first portion 401 connected to the pole post 201, and a second portion 402 for connecting to the pole tab 301, the second portion 402 being embedded in the receiving groove 1011. The folded portion 102 abuts against the first portion 401 after being folded, and the recessed platform 1022 abuts against the second portion 402 via the pole tab 301.

[0074] Finally, multiple bosses 202 are spaced apart on the cover plate 2, with each boss corresponding to a protrusion. One boss 202 has an injection hole 2021, and another protrusion has an outlet hole 1013. The cover plate 2 has an explosion-proof valve mounting hole 203, and at least one boss 202 is provided between the explosion-proof valve mounting hole 203 and the pole post 201, corresponding to the explosion-proof valve mounting hole 203. The lower plastic 1 has a vent hole 1015.

[0075] In the preferred embodiment of the above cover plate assembly, the specific configuration and arrangement of the cover plate 2, the lower plastic 1, etc. can still be referred to the descriptions in the above exemplary embodiments. Furthermore, in this preferred embodiment, the beneficial effects brought about by the design of the cover plate 2, the lower plastic 1, etc. can also be referred to the descriptions in the above exemplary embodiments.

[0076] The cover assembly of this embodiment adopts the above design. Through the setting of the lower plastic 1, the electrode group 3 itself and the electrode tab 301 of the electrode group 3 can be fixed. When the battery is subjected to external force impact, it can prevent the electrode tab 301 from being torn or inserted into the electrode group 3 due to external force, and reduce the shaking of the electrode group 3 in the housing 5, thereby reducing the risk of battery short circuit and improving battery safety performance.

[0077] An embodiment of the third aspect of this application provides a battery, combined with Figures 13 to 14 As shown, the battery is equipped with a cover plate assembly as described above.

[0078] The battery in this embodiment has good structural strength due to the above-mentioned cover plate assembly. It can withstand external impact when it is hit, so as to protect the electrode group 3 inside the housing 5. At the same time, it can fix the electrode group 3 itself and the tabs 301 on the electrode group 3, reduce the shaking of the electrode group 3 inside the housing 5, and prevent the tabs 301 from being torn due to external force, thereby reducing the risk of short circuit of the battery and improving the safety performance of the battery.

[0079] The above descriptions are merely some embodiments of this application and are not intended to limit this application. The technical features or structures in the foregoing different embodiments can be arbitrarily combined to form other specific technical solutions as needed. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this application should be included within the protection scope of the claims of this application.

Claims

1. A type of plastic material suitable for placement on the cover plate (2) of a battery, characterized in that: It includes a body (101) that conforms to the shape of the cover plate (2), and a folding portion (102) that can be folded relative to the body (101). The body (101) has a protrusion protruding to one side in the thickness direction of the lower plastic (1), the protrusion is formed by the lower plastic (1) itself, and a receiving groove (1011) for accommodating the tab (301) is formed on the lower plastic (1). The folded portion (102) is provided with a support platform (1021) and a recessed platform (1022) formed on the folded portion (102) corresponding to the receiving groove (1011). The support platform (1021) and the recessed platform (1022) both protrude to a first side in the thickness direction of the folded portion (102). The folded portion (102) after folding can abut against the tab (301) through the recessed platform (1022) and abut against the body (101) through the support platform (1021).

2. The lower plastic according to claim 1, characterized in that: The body (101) has a support protrusion (1012) on at least one side in the width direction, and the support protrusion (1012) is opposite to the protrusion direction of the protrusion. The support protrusion (1012) is flush with the second side of the folded portion (102) in the thickness direction after folding, and both are used to abut against the electrode group (3) of the battery.

3. The lower plastic according to claim 2, characterized in that: The folding portion (102) consists of two parts located at both ends of the body (101) along its length, and the supporting protrusion (1012) is provided at both ends of the body (101) along its length. Each of the folding portions (102) is provided with a notch (1023) for avoiding the support protrusion (1012) at the corresponding end.

4. The lower plastic according to claim 1, characterized in that: The folding portion (102) is integrally formed with the body (101), and a glue-reducing groove (103) is provided at the connection between the folding portion (102) and the body (101).

5. The lower plastic according to any one of claims 1 to 4, characterized in that: The folded portion (102) has a notch (104) at one end where it connects to the body (101), and the notch (104) extends along the width direction of the body (101); and / or, Corresponding to the settling platform (1022), a settling groove (1024) is formed on the second side of the folded portion (102) in the thickness direction, and a plurality of reinforcing ribs (1025) are provided in the settling groove (1024).

6. A cover plate assembly, characterized in that: It includes a cover plate (2), a lower plastic (1) provided on the cover plate (2) according to any one of claims 1 to 5, and an electrode post (201) passing through the lower plastic (1) and the cover plate (2).

7. The cover plate assembly according to claim 6, characterized in that: Corresponding to the protrusion, the cover plate (2) is formed with a boss (202) protruding to a first side in the direction of its own thickness, and a relief groove (2022) is formed on the cover plate (2), and the protrusion is located in the relief groove (2022); The pole post (201) and the boss (202) are spaced apart, and the pole post (201) has a protruding section protruding to a first side in the thickness direction of the cover plate (2). On the first side in the thickness direction of the cover plate (2), the protrusion height of the boss (202) is greater than the protrusion height of the protruding section.

8. The cover plate assembly according to claim 7, characterized in that: The cover plate assembly includes a connecting piece (4) disposed on the side of the lower plastic (1) away from the cover plate (2); The connecting piece (4) has a first part (401) connected to the pole post (201) and a second part (402) for connecting to the pole tab (301), the second part (402) being embedded in the receiving groove (1011); The folded portion (102) abuts against the first portion (401) after being folded, and the sinker (1022) abuts against the second portion (402) through the tab (301).

9. The cover plate assembly according to claim 7 or 8, characterized in that: The protrusions (202) are multiple protrusions spaced apart on the cover plate (2), and the protrusions are arranged one-to-one with the protrusions (202); One of the bosses (202) is provided with an injection hole (2021), and corresponding to the injection hole (2021), one of the protrusions is provided with an outlet hole (1013); and / or, the cover plate (2) is provided with an explosion-proof valve mounting hole (203), and at least one of the bosses (202) is provided between the explosion-proof valve mounting hole (203) and the pole post (201), and corresponding to the explosion-proof valve mounting hole (203), the lower plastic (1) is provided with a vent hole (1015).

10. A battery, characterized in that: The battery is provided with a cover plate assembly as described in any one of claims 6 to 9.

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