Lower plastic, cover plate assembly and battery

Abstract

The application relates to the technical field of power batteries, in particular to 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 is formed by the lower plastic itself, and an accommodating groove for accommodating a tab is formed on the lower plastic. Corresponding to the accommodating groove, a sunken platform is formed on the folding part. The lower plastic provided by the application provides an accommodating space for the tab through the arrangement of the accommodating groove on the body, and the accommodating groove limits and restricts the tab to prevent the tab from shaking randomly in the shell. In addition, through the arrangement of the folding part, the sunken platform of the folding part can abut against the tab, thereby stably keeping the tab in the accommodating groove. The folding part is arranged on one side of the via hole to separate the pole column and the pole group, prevents the pole column from colliding with the pole group and causing damage to the pole group, thereby reducing the risk of short circuit of the battery and improving the safety performance of the battery.

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 tabs are easily torn and damaged by the force, potentially causing them to insert backwards into the electrode assembly, leading to 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 through hole for the electrode post to pass through, and a protrusion protruding to one side in the thickness direction of the lower plastic. The protrusion is spaced apart from the through hole, and the protrusion is formed by the lower plastic itself, and a receiving groove for accommodating the electrode tab is formed on the lower plastic. Corresponding to the receiving groove, a countersunk platform is formed on the folded portion. After folding, the folded portion blocks one side of the through hole and can abut against the electrode tab through the countersunk 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 and the side of the folded portion away from the sink in the thickness direction are flush, and both are used to abut against the electrode assembly of the battery.

[0006] Furthermore, the folding portion consists of two portions located at both ends of the body along its length. Each folding portion has a first portion and a second portion. The first portion is connected to the body, and the recessed platform is located on the second portion. At least one end of the body along its length is provided with two spaced-apart support protrusions. The first portion of the folding portion at the corresponding end is located between the two support protrusions, and the width of the first portion is smaller than the width of the second portion.

[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 that connects to the main body is provided with a notch, which extends along the width direction of the main body.

[0009] Compared with related technologies, this application has the following advantages: (1) The lower plastic body described in this application, through the setting of the receiving groove on the body, provides a receiving space for the tab and constitutes a limiting constraint on the tab to prevent the tab from shaking freely in the shell. Furthermore, through the setting of the folded part, the countersunk platform of the folded part can abut against the tab, thereby holding the tab stably in the receiving groove and further fixing the position of the tab. When the battery is impacted, it can effectively prevent the tab from shifting and tearing or being inserted backward into the electrode assembly. At the same time, the folded part is placed on the through hole side to separate the terminal post and the electrode assembly, preventing the terminal post and the electrode assembly from colliding and causing damage to the electrode assembly, thereby reducing the risk of short circuit in 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. Furthermore, the support protrusions are located on both sides of the first part, which not only support the electrode assembly but also constitute a limiting constraint on the folding parts in the width direction of the main body to prevent the second part from shifting and ensure the fixing effect of the folding parts on the terminals.

[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 body can be reduced, further reducing the resistance of the folding part, making the folding part easier to fold relative to the body, thereby further facilitating the assembly operation of the cover plate 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 groove is formed on the cover plate, with the protrusion located in the groove; the pole post has a protruding section protruding to a first side in the thickness direction of the cover plate, and 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 an electrode post connecting portion connected to the electrode post, and an electrode tab connecting portion for connecting to the electrode tab, the electrode tab connecting portion being embedded in the receiving groove.

[0017] Furthermore, the bosses are two spaced apart on the cover plate, and the protrusions correspond one-to-one with the bosses; one of the bosses is provided with an injection hole, and corresponding to the injection hole, the other protrusion is provided with an outlet hole, and there is an avoidance notch on the electrode tab connection to avoid the outlet hole; and / or, the cover plate is provided with an explosion-proof valve mounting hole, and one of the bosses is provided between the explosion-proof valve mounting hole and the electrode 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 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 tabs from being torn or inserted into the electrode assembly due to external force, thereby reducing the risk of short circuit of the battery and improving the safety performance of the battery.

[0019] (2) The groove on the cover plate provides space for the protrusion on the lower plastic. At the same time, the protrusion height of the boss corresponding to the 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 connection part of the connecting piece is embedded in the receiving groove, which not only limits the connecting piece and facilitates the connection between it and the pole, but also facilitates the connection between the connecting piece and 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 structure of the lower plastic and the cover plate described in the embodiments of this application; Figure 2 This is a schematic diagram of the structure of the lower plastic and the other side of the cover plate as described in the embodiment of this application; Figure 3 This is a front view of the lower plastic sheet facing the electrode assembly as described in the embodiments of this application; Figure 4 for Figure 1 A sectional view at the location shown in AA; 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 for Figure 4 Enlarged view of point D in the middle; Figure 8 This is a schematic diagram of the structure when the cover plate assembly described in the embodiment of this application is connected to the electrode group; Figure 9 This is a schematic diagram of the connection between the folded cover assembly and the electrode assembly as described in the embodiments of this application; Figure 10 This is a front view of the lower plastic sheet facing the electrode assembly when the cover plate assembly described in this application is connected to the electrode assembly; 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 13This is a schematic diagram of the overall structure of the battery cell described in the embodiments of this application; Figure 14 for Figure 13 Enlarged view of point G in the middle; Explanation of reference numerals in the attached figures: 1. Lower plastic part; 101. Main body; 1011. Receiving groove; 1012. Support protrusion; 1013. Auxiliary support protrusion; 1014. Liquid outlet; 1015. Vent hole; 1016. Score; 1017. Connecting rib; 102. Folded part; 102a. First part; 102b. Second part; 1021. Recessed platform; 103. Reduction groove; 104. Notch; 2. Cover plate; 201. Boss; 2011. Injection hole; 202. Explosion-proof valve mounting hole; 3. Pole post; 301. Connecting piece; 3011. Pole post connecting part; 3012. Pole lug connecting part; 3013. Clearance notch; 4. Electrode assembly; 401. Electrode tab; 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 "connecting piece" 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 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, after the tab 401 is welded to the electrode assembly 4, the tab 401 is usually loosely positioned between the electrode assembly 4 and the cover plate 2. When the battery is under vibration or subjected to external impact, the tab 401 is easily torn and damaged by the external force, which can easily cause the tab 401 to be inserted backward into the electrode assembly 4, resulting in a short circuit inside the electrode assembly 4, posing 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 4 As 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] Among them, continue to combine Figure 7 As shown, the body 101 has a through hole for the electrode post 3 to pass through, and a protrusion protruding from one side in the thickness direction of the lower plastic 1. The protrusion and the through hole are spaced apart, and the protrusion is formed by the lower plastic 1 itself, and a receiving groove 1011 for accommodating the electrode tab 401 is formed on the lower plastic 1. Figure 8 , Figure 9 As shown, corresponding to the receiving groove 1011, a countersunk platform 1021 is formed on the folded portion 102. The folded portion 102 is placed on one side of the through hole after folding, and can abut against the tab 401 through the countersunk platform 1021.

[0035] Therefore, through the arrangement of the receiving groove 1011 on the main body 101, the receiving groove 1011 provides a receiving space for the tab 401 and constitutes a limiting constraint on the tab 401 to prevent the tab 401 from shaking freely within the housing 5. Furthermore, through the arrangement of the folding part 102, the recess 1021 of the folding part 102 can abut against the tab 401, thereby stably holding the tab 401 in the receiving groove 1011 and further fixing the position of the tab 401. When the battery is impacted, it can effectively prevent the tab 401 from shifting and tearing or being inserted backwards into the electrode assembly 4. At the same time, the folding part 102 is positioned on the through hole side to separate the terminal post 3 and the electrode assembly 4, preventing the terminal post 3 from colliding with the electrode assembly 4 and causing damage to the electrode assembly 4, thereby reducing the risk of short circuit in the battery and improving the battery's safety performance.

[0036] Based on the above general description, specifically, 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 and the side of the folded portion 102 after folding away from the recessed platform 1021 in the thickness direction are disposed flush, and both are used to abut against the battery electrode group 4.

[0037] 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 group 4 facing the cover plate 2, forming a support for the electrode group 4 and ensuring that the electrode group 4 is evenly stressed. This can improve the fixing effect of the electrode group 4 in the housing 5, prevent the electrode group 4 from shaking in the housing 5, thereby reducing the risk of the tab 401 tearing or short circuit caused by the shaking of the electrode group 4, and further improving the safety performance of the battery.

[0038] In some exemplary embodiments, there are two folding portions 102 located at both ends of the body 101 along its length. Each folding portion 102 has a first portion 102a and a second portion 102b. The first portion 102a is connected to the body 101, and the recessed platform 1021 is disposed on the second portion 102b. At least one end of the body 101 along its length has two spaced-apart support protrusions 1012. The first portion 102a of the corresponding end of the folding portion 102 is located between the two support protrusions 1012, and the width of the first portion 102a is smaller than the width of the second portion 102b.

[0039] Therefore, by configuring the folding portions 102 as two separate units located 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 terminals 401 of the electrode assembly 4. Furthermore, the support protrusions 1012 are located on both sides of the first portion 102a, providing support for the electrode assembly 4 while also constraining the folding portions 102 in the width direction of the main body 101 to prevent the second portion 102b from shifting, ensuring the effective fixing of the folding portions 102 to the terminals 401.

[0040] In specific implementation, the first part 102a of this embodiment is positioned on the side of the pole post 3 facing the pole group 4. Therefore, the support protrusions 1012 on both sides of the first part 102a can also limit the first part 102a, ensuring its protective effect on the pole group 4. Furthermore, the support protrusions 1012 are located at the four corners of the body 101, and an auxiliary support protrusion 1012 is also provided in the middle of the body 101, enabling the middle part of the body 101 to support the pole group 4, further improving the fixing effect on the pole group 4.

[0041] Combination 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.

[0042] By setting the adhesive reduction groove 103, the material thickness at the connection between the folding part 102 and the main body 101 can be reduced, making it easier for the folding part 102 to fold relative to the main body 101. This ensures the connection effect between the folding part 102 and the main body 101 while facilitating the assembly operation of the cover plate assembly.

[0043] Furthermore, in some exemplary embodiments, the notch 104 reduces the width of the connection between the folding portion 102 and the body 101, further reducing the resistance to folding the folding portion 102 and making it easier for the folding portion 102 to fold relative to the body 101, thereby further facilitating the assembly operation of the cover plate assembly.

[0044] In this embodiment, the lower plastic 1 adopts the design described above. The receiving groove 1011 on the main body 101 provides a receiving space for the tab 401 and constitutes a limiting constraint on the tab 401, preventing it from moving freely within the housing 5. Furthermore, the folding portion 102's recessed platform 1021 abuts against the tab 401, thus stably holding the tab 401 within the receiving groove 1011 and further fixing its position. This effectively prevents the tab 401 from shifting and tearing or being inserted backwards into the electrode assembly 4 when the battery is impacted. Simultaneously, the folding portion 102 blocks the through-hole side to separate the terminal post 3 and the electrode assembly 4, preventing collisions between the terminal post 3 and the electrode assembly 4 and thus reducing the risk of short circuits and improving battery safety performance, demonstrating excellent practicality.

[0045] An embodiment of the second aspect of this application provides a cover plate assembly.

[0046] In the cover plate assembly of this embodiment, combined with Figure 1 , Figure 2 , Figure 8 and Figure 9 As shown, the overall design includes a cover plate 2, a lower plastic 1 as described above disposed on the cover plate 2, and an electrode post 3 passing through the lower plastic 1 and the cover plate 2.

[0047] In this embodiment, the cover plate 2, through the aforementioned lower plastic 1, can fix the tabs 401 of the electrode group 4. When the battery is subjected to external impact, it can prevent the tabs 401 from being torn or inserted backwards into the electrode group 4 due to external force, thereby reducing the risk of short circuit in the battery and improving the safety performance of the battery.

[0048] Based on the above overall introduction, specifically, the cover plate 2 of this embodiment has a rectangular structure to adapt to the battery casing 5 of the directional battery, and the cover plate 2 is provided with two pole posts 3, which are respectively located at both ends of the length direction of the cover plate 2 to adapt to the positive and negative pole tabs 401 of the pole group 4.

[0049] Furthermore, it is understood that in related technologies, a certain space needs to be reserved between the lower plastic 1 of the cover plate assembly and the electrode group 4 to accommodate the electrode tabs 401 of the electrode group 4. In this embodiment, however, as... Figure 11 As shown, the receiving groove 1011 on the lower plastic 1 provides storage space for the tab 401, thus eliminating the need to reserve space between the lower plastic 1 and the electrode group 4, thereby improving the utilization rate of the internal space of the battery casing 5 and thus contributing to the improvement of battery capacity.

[0050] In some exemplary embodiments, corresponding to the protrusion, the cover plate 2 has a boss 201 formed on a first side protruding in the thickness direction, and a groove is formed on the cover plate 2, in which the protrusion is located. The pole post 3 has a protruding section protruding in the first side in the thickness direction of the cover plate 2, and the protrusion height of the boss 201 is greater than the protrusion height of the protruding section.

[0051] The groove 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 201 corresponding to the groove is greater than the protrusion height of the protruding end of the electrode post 3. When the cover plate 2 is subjected to external force, the boss 201 can withstand the impact, so as to avoid the electrode post 3 being directly subjected to external force and causing damage to the tab 401 and electrode group 4, thereby improving the installation performance of the battery.

[0052] Specifically, the height difference d between the top of the boss 201 and the top of the pole post 3 satisfies 1.0mm≤d≤2.0mm. In specific implementation, 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 on the pole post.

[0053] In some exemplary embodiments, the cover plate assembly includes a connecting piece 301 disposed on the side of the lower plastic 1 away from the cover plate 2. The connecting piece 301 has an electrode post connecting portion 3011 connected to the electrode post 3, and an electrode tab connecting portion 3012 for connecting to the electrode tab 401, the electrode tab connecting portion 3012 being embedded in the receiving groove 1011.

[0054] By setting the connecting piece 301, a stable electrical connection between the pole post 3 and the tab 401 can be achieved. At the same time, the tab connecting part 3012 of the connecting piece 301 is embedded in the receiving groove 1011, which not only limits the connecting piece 301 and facilitates the connection between it and the pole post 3, but also facilitates the connection between the connecting piece 301 and the tab 401.

[0055] In specific implementation, such as Figure 13 , Figure 14 As shown, the connecting piece 301 in this embodiment can connect the tabs 401 of the two pole groups 4. Based on this, after the two pole groups 4 are brought together, the ends of the two pole groups 4 facing the cover plate assembly can abut against the folded portion 102 of the lower plastic 1, so that the folded portion 102 maintains the folded state that fixes the tabs 401, thereby ensuring the fixing effect of the folded portion 102 on the tabs 401.

[0056] It is worth mentioning that, combined with Figure 10 As shown, in this embodiment, in order to ensure the fixing effect of the folded portion 102 in the lower plastic 1 on the tab 401, the sum of the areas S1 of the tops of the countersunk platforms 1021 on the two folded portions 102 satisfies: 120mm.2 ≤S1≤600mm 2 The sum of the welding areas S2 of the two connecting pieces 301 and the two tabs 401 satisfies: 80mm 2 ≤S2≤400mm 2 Furthermore, the ratio of the area S1 of the top of the countersunk platform 1021 to the welding area S2 of the connecting piece 301 and the tab 401 satisfies: 35% ≤ S2 / S1 ≤ 75%. This ensures that there is sufficient contact area between the countersunk platform 1021 and the tab 401, and sufficient connection area between the tab 401 and the connecting piece 301.

[0057] In addition, such as Figure 12 As shown, the depth H of the recessed platform 1021 satisfies: 1.2mm≤H≤3.5mm, and the inclination angle α of the side wall of the recessed platform 1021 satisfies: 20°≤α≤70°, so as to ensure that the recessed platform 1021 has a certain elasticity, and while fixing the electrode 401 by abutting against it, it avoids the recessed platform 1021 damaging the electrode 401 itself and the solder mark of the electrode 401.

[0058] To verify the rationality of the selection of the top area S1 of the sinker 1021, the welding area S2 of the connecting piece 301 and the tab 401, the depth H of the sinker 1021, and the tilt angle α of the side wall of the sinker 1021 in this embodiment, the verification is shown in Table 1.

[0059] Table 1

[0060] As shown in Table 1, if at least one of the following three conditions is not met, the fixing effect of the sinker 1021 of the folded part 102 on the electrode 401 is poor, and there is a risk of the electrode 401 being inserted upside down.

[0061] Furthermore, if at least one of the following conditions is not met—the depth H of the recessed platform 1021 and the tilt angle α of the sidewall of the recessed platform 1021—the elasticity of the recessed platform 1021 is poor, posing a risk of damaging the tab 401 itself and its solder marks when fixing the tab 401. This embodiment, by selecting the area S1 of the top of the recessed platform 1021, the welding area S2 between the connecting piece 301 and the tab 401, as well as the depth H of the recessed platform 1021 and the tilt angle α of the sidewall of the recessed platform 1021, ensures the effective fixing of the tab 401, thereby improving the safety and reliability of the battery.

[0062] In some exemplary embodiments, there are two bosses 201 spaced apart on the cover plate 2, with each boss 201 corresponding to a protrusion. One boss 201 has an injection hole 2011, and corresponding to the injection hole 2011, the other protrusion has an outlet hole 1014, with a clearance notch 3013 on the second part 102b to avoid the outlet hole 1014. By placing the boss 201 between the explosion-proof valve mounting hole 202 and the terminal post 3, the hot gas discharged from the explosion-proof valve can be prevented from affecting the terminal post 3, thus achieving the function of thermoelectric separation and improving battery safety performance.

[0063] Meanwhile, in some exemplary embodiments, the cover plate 2 is provided with an explosion-proof valve mounting hole 202, and a boss 201 is provided between the explosion-proof valve mounting hole 202 and the pole post 3. Corresponding to the explosion-proof valve mounting hole 202, the lower plastic 1 is provided with a vent hole 1015.

[0064] By placing the injection hole 2011 on the boss 201, the weakening effect of the injection hole 2011 on the structural strength of the cover plate 2 can be effectively reduced, so as to ensure that the cover plate 2 has sufficient structural strength.

[0065] In specific implementation, such as Figure 5 As shown, the vent 1015 allows gas inside the battery to escape through the vent 1015 and then through the explosion-proof valve in the event of thermal runaway of the electrode assembly 4. To facilitate the installation of the explosion-proof valve, the body 101 of the lower plastic 1 in this embodiment is recessed into the side where the electrode assembly 4 is located, corresponding to the position of the explosion-proof valve mounting hole 202, to provide installation space for the explosion-proof valve. Based on this, the vent 1015 in this embodiment is located at the bottom of this recess.

[0066] Furthermore, the bottom of the aforementioned groove is provided with multiple 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 adjacent through holes 1016. This divides the bottom of the groove into two parts by the through holes 1016, and the two parts are connected only by the connecting rib 1017. Thus, when the electrode group 4 experiences thermal runaway 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, and the high temperature of the gas can melt and break the connecting rib 1017, causing the part of the groove 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.

[0067] Furthermore, the aforementioned auxiliary support protrusions 1012 are configured as two separate locations on both sides of the groove along the width direction of the lower plastic 1, and the auxiliary support protrusions 1012 are flush with the end face of the groove facing the pole group 4.

[0068] It is worth noting that, regarding the cover plate assembly of this embodiment, based on the above exemplary embodiments, in specific implementation, as a preferred embodiment, it is still composed of... Figures 8 to 12 As shown, it may include, for example, a cover plate 2, upper and lower plastics 1 disposed on the cover plate 2, and pole posts 3 passing through the lower plastics 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 through hole for the electrode post 3 to pass through, and a protrusion protruding to one side in the thickness direction of the lower plastic 1. The protrusion is spaced apart from the through hole, and the protrusion is formed by the lower plastic 1 itself, forming a receiving groove 1011 on the lower plastic 1 for accommodating the electrode tab 401. Corresponding to the receiving groove 1011, a countersunk platform 1021 is formed on the folding portion 102. After folding, the folding portion 102 blocks one side of the through hole and can abut against the electrode tab 401 through the countersunk platform 1021.

[0070] Corresponding to the protrusion, the cover plate 2 is formed with a boss 201 protruding to a first side in the thickness direction of itself, and a groove is formed on the cover plate 2. The protrusion is located in the groove. The pole post 3 has a protruding section protruding to a first side in the thickness direction of the cover plate 2. The protrusion height of the boss 201 is greater than the protrusion height of the protruding section.

[0071] Furthermore, 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 protrusions. The support protrusions 1012 and the side of the folded portion 102 after folding are flush with each other in the thickness direction away from the recessed platform 1021, and are both used to abut against the battery electrode group 4. There are two folded portions 102 at both ends of the main body 101 in the length direction. Each folded portion 102 has a first part 102a and a second part 102b. The first part 102a is connected to the main body 101, and the recessed platform 1021 is provided on the second part 102b. At least one end of the main body 101 in the length direction has two support protrusions 1012 arranged at intervals. The first part 102a of the folded portion 102 at the corresponding end is located between the two support protrusions 1012, and the width of the first part 102a is smaller than the width of the second part 102b.

[0072] Furthermore, the folding portion 102 is integrally formed with the main body 101, and a reducing groove 103 is provided at the connection between the folding portion 102 and the main body 101. A notch 104 is provided at the end where the folding portion 102 connects to the main body 101, and the notch 104 extends along the width direction of the main body 101. The cover plate assembly includes a connecting piece 301 located on the side of the lower plastic 1 away from the cover plate 2. The connecting piece 301 has an electrode post connecting portion 3011 connected to the electrode post 3, and an electrode tab connecting portion 3012 for connecting to the electrode tab 401, the electrode tab connecting portion 3012 being embedded in the receiving groove 1011.

[0073] Finally, there are two bosses 201 spaced apart on the cover plate 2, with each boss corresponding to a protrusion. One boss 201 has an injection hole 2011, and corresponding to the injection hole 2011, the other protrusion has an outlet hole 1014, with a clearance notch 3013 on the second part 102b to avoid the outlet hole 1014. Meanwhile, the cover plate 2 has an explosion-proof valve mounting hole 202, and a boss 201 is located between the explosion-proof valve mounting hole 202 and the pole post 3, corresponding to the explosion-proof valve mounting hole 202. A vent hole 1015 is located on the lower plastic 1.

[0074] In the preferred embodiment of the above cover plate assembly, the specific settings and arrangements of the cover plate 2, the lower plastic 1, the connecting piece 301, 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, the connecting piece 301, etc. can also be referred to the descriptions in the above exemplary embodiments.

[0075] The cover plate assembly of this embodiment adopts the above design. Through the setting of the lower plastic 1, the tabs 401 of the electrode group 4 can be fixed. When the battery is subjected to external force impact, the tabs 401 can be prevented from being torn or inserted into the electrode group 4 due to external force, thereby reducing the risk of short circuit of the battery and improving the safety performance of the battery.

[0076] An embodiment of the third aspect of this application provides a battery, such as Figure 13 , Figure 14 As shown, the battery is equipped with a cover plate assembly as described above.

[0077] 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 4 inside the housing 5. At the same time, it can fix the electrode tabs 401 of the electrode group 4, preventing the electrode tabs 401 from being torn or inserted into the electrode group 4 due to external force, thereby reducing the risk of short circuit and improving the safety performance of the battery.

[0078] 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 (1) suitable for placement on a battery cover (2), 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) is provided with a through hole for the electrode post (3) to pass through, and a protrusion protruding to one side in the thickness direction of the lower plastic (1). The protrusion is spaced apart from the through hole, and the protrusion is formed by the lower plastic (1) itself, and a receiving groove (1011) for accommodating the electrode tab (401) is formed on the lower plastic (1). Corresponding to the receiving groove (1011), a recess (1021) is formed on the folded portion (102). The folded portion (102) is positioned on one side of the through hole after folding, and can abut against the tab (401) through the recess (1021).

2. The lower plastic (1) 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) and the folded portion (102) are flush with each other on the side away from the sinker (1021) in the thickness direction, and both are used to abut against the electrode group (4) of the battery.

3. The lower plastic (1) according to claim 2, characterized in that: The folding portions (102) are two located at both ends of the body (101) along its length. Each folding portion (102) has a first portion (102a) and a second portion (102b). The first portion (102a) is connected to the body (101), and the sinking platform (1021) is located on the second portion (102b). At least one end of the body (101) along its length is provided with two spaced-apart support protrusions (1012), and the first part (102a) of the folded portion (102) at the corresponding end is located between the two support protrusions (1012), and the width of the first part (102a) is smaller than the width of the second part (102b).

4. The lower plastic (1) according to any one of claims 1 to 3, 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 (1) according to claim 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).

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 (3) 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 (201) protruding to a first side in the direction of its own thickness, and a groove is formed on the cover plate (2), and the protrusion is located in the groove; The pole post (3) has a protruding section that protrudes to a first side in the thickness direction of the cover plate (2), and the protrusion height of the boss (201) 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 (2) assembly includes a connecting piece (301) disposed on the side of the lower plastic (1) away from the cover plate (2); The connecting piece (301) has a pole post connecting part (3011) connected to the pole post (3) and a pole tab connecting part (3012) for connecting to the pole tab (401), the pole tab connecting part (3012) being embedded in the receiving groove (1011).

9. The cover plate assembly according to claim 8, characterized in that: The boss (201) is two that are spaced apart on the cover plate (2), and the protrusion is provided in a one-to-one correspondence with the boss (201); One of the bosses (201) is provided with an injection hole (2011), and corresponding to the injection hole (2011), one of the protrusions is provided with an outlet hole (1014), and an avoidance notch (3013) is provided on the electrode connecting part (3012) to avoid the outlet hole (1014); and / or, the cover plate (2) is provided with an explosion-proof valve mounting hole (202), and one of the bosses (201) is provided between the explosion-proof valve mounting hole (202) and the electrode post (3), and corresponding to the explosion-proof valve mounting hole (202), 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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