Battery cover plate assembly capable of improving air tightness and power battery

Abstract

The invention discloses a battery cover plate assembly capable of improving air tightness, the battery cover plate assembly comprises a cover plate body and a pole assembly assembled on the cover plate body, the pole assembly comprises a pole body and a sealing ring, the pole body penetrates through a pole hole in the cover plate body, the space between the pole body and the pole hole is filled with the sealing ring, and the cover plate body is provided with a cover plate step; the sealing ring comprises an inner wall and an outer wall spaced from the inner wall by a target width, the inner wall is matched with the side wall of the pole body, gradient steps matched with the steps of the cover plate and a transition connecting surface are formed in the width direction of the sealing ring, the gradient steps comprise at least one step, and each step comprises a step plane and a step connecting surface; the step planes and the transition connecting faces or every two adjacent step planes are connected through a step connecting face, and the inner wall is an inclined face and / or at least one step connecting face in at least one step is an inclined face. The sealing ring is designed into the special-shaped structure with the slope, so that the sealing effect of the pole assembly is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery devices, and particularly relates to a battery cover plate assembly and a power battery capable of improving airtightness. Background Art

[0002] As a clean energy source, electric power is increasingly widely used. As a device that can store electric power, the safety of the battery is also crucial. Therefore, the battery pole column of the battery cover plate needs to be sealed with a sealing ring to avoid, to a certain extent, the leakage of the electrolyte or other chemical substances of the power battery from the inside of the battery, which may cause damage to the environment or pose a safety hazard to the equipment. It can also prevent external moisture or dust from entering the battery to a certain extent and affect the battery.

[0003] At present, for traditional battery cover plate assemblies, such as the solution disclosed in the publication number CN221783324U, a traditional annular sealing ring is adopted, and the design is simple. During the subsequent use of the battery, acid creep often occurs at the contact between the sealing ring and the pole column and between the sealing ring and the battery cover. During the use of the battery, due to long-term jolting, the sealing is likely to become loose. These situations will affect the service life of the battery and bring unnecessary troubles to users. Therefore, how to improve the sealing effect of the pole column is an urgent problem to be solved. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a battery cover plate assembly and a power battery capable of improving airtightness, which solves the problem of poor sealing effect of the pole column in the prior art.

[0005] According to one aspect of the present application, a battery cover plate assembly capable of improving airtightness is disclosed. The battery cover plate assembly includes a cover plate body and a pole column assembly assembled on the cover plate body. A pole column hole is provided on the cover plate body, and the pole column assembly is assembled in cooperation with the pole column hole. The pole column assembly includes a pole column body and a sealing ring. The pole column body penetrates through the pole column hole, and a sealing gap with a compression margin is formed between the pole column body and the cover plate body after the pole column body penetrates through the pole column hole. The sealing gap is filled by compressing the sealing ring. A cover plate step is provided on the cover plate body on one side of the sealing gap. The sealing ring includes an inner wall and an outer wall spaced from the inner wall by a target width. The inner wall cooperates with the side wall of the column body of the pole column body. A gradient step and a transition connection surface matching the cover plate step are formed in the target width direction of the sealing ring. The gradient step includes at least one step, and each step includes a step plane and a step connection surface. The step plane and the transition connection surface or between adjacent two step planes are connected by one step connection surface. The inner wall is an inclined plane and / or at least one of the step connection surfaces in at least one of the steps is an inclined plane.

[0006] In some embodiments, the gradient step is arranged to slope down or up from the inner wall to the outer wall along the target width direction.

[0007] In some embodiments, the pole column assembly further includes pole column encapsulation. After the pole column body penetrates through the pole column hole, a encapsulation gap is formed between the pole column body and the cover plate body, and the encapsulation gap is filled with the pole column encapsulation.

[0008] In some embodiments, a groove is formed on the side wall of the column body of the pole column body, and the pole column encapsulation is injection molded to fill the groove.

[0009] In some embodiments, the battery cover plate assembly further includes an explosion-proof component located on the cover plate body. The explosion-proof component includes an explosion-proof valve that cooperates with an explosion-proof hole formed on the cover plate body. The sealing ring and the explosion-proof valve are both made of rubber material.

[0010] In some embodiments, the explosion-proof valve is made of EDPM or TPV or fluororubber material.

[0011] In some embodiments, the explosion-proof valve includes an outer ring wall. A ring platform protrudes outward from the outer ring wall. A ring groove is formed on the cover plate body. The ring platform is arranged in the ring groove. The explosion-proof component further includes a pressing plate. After the ring platform is arranged in the ring groove, the pressing plate presses the other side of the ring platform, and the pressing plate is welded to the cover plate body.

[0012] In some embodiments, the pressing plate is located on the top surface or the bottom surface of the cover plate body.

[0013] In some embodiments, a battery cell cover plate is arranged above the pole column assembly. A conductive material is coated on the top surface of the explosion-proof valve. When the explosion-proof valve bulges to a first target height under air pressure, the conductive material contacts a circuit contact point on the battery cell cover plate, and the working data of the battery cell is read, so that the battery management system determines an abnormal battery cell based on the working data, where the working data at least includes the battery cell temperature.

[0014] In some embodiments, a puncture pin is further arranged above the explosion-proof valve. The puncture pin is located above the battery cell cover plate. When the explosion-proof valve bulges to a second target height under air pressure, it is punctured by the puncture pin to release pressure, and the second target height is higher than the first target height.

[0015] In some embodiments, the size of the explosion-proof valve is determined based on the pressure storage requirement.

[0016] In some embodiments, the battery cover plate assembly further includes a plastic part, and the plastic part supports the bottom of the cover plate body.

[0017] In some embodiments, the plastic part is disposed around the pole column assembly. The plastic part includes a plurality of abutting parts, and one of the plurality of abutting parts abuts below the sealing ring, one abuts against the bottom of the cover plate body, and one abuts against the side wall of the column body of the pole column.

[0018] In some embodiments, both the plastic part and the sealing ring are made of fluororubber, the plastic part and the sealing ring are integrally formed, and the explosion-proof valve is made of EPDM.

[0019] In some embodiments, both the plastic part and the sealing ring are made of fluororubber, and the explosion-proof valve is made of EPDM.

[0020] In some embodiments, the plastic part integrally surrounds the pole column assembly and the explosion-proof valve. Both the plastic part, the sealing ring and the explosion-proof valve are made of EPDM, and the plastic part, the sealing ring and the explosion-proof valve are integrally formed.

[0021] In some embodiments, a first connecting part and a second connecting part are provided on the plastic part, a third connecting part is formed on the sealing ring, and a fourth connecting part is provided on the explosion-proof valve. After the first connecting part cooperates with the third connecting part and the second connecting part cooperates with the fourth connecting part, the plastic part is integrally installed around the pole column assembly and the explosion-proof valve.

[0022] In some embodiments, the plastic part is made of EPDM or TPV, both the third connecting part and the sealing ring are made of fluororubber and are integrally formed, both the fourth connecting part and the explosion-proof valve are made of EPDM and are integrally formed.

[0023] In some embodiments, the sealing ring is integrally injection-molded, the sealing ring integrally surrounds the pole column assembly and the explosion-proof valve, and both the sealing ring and the explosion-proof valve are made of EPDM.

[0024] According to another aspect of the present application, a power battery is also disclosed. The power battery includes the battery cover plate assembly capable of improving airtightness as described in any one of the above.

[0025] The present solution includes but is not limited to the following beneficial effects: (1) The inclined surface design of the sealing ring can increase the contact area between the sealing ring and the pole column body, enabling the sealing ring to fit more effectively on the surface of the pole column body, thereby enhancing the sealing performance. Moreover, the inclined surface design can make the pressure more evenly distributed on the contact surface of the sealing ring when the sealing ring is compressed, reducing the phenomenon of local stress concentration and lowering the risk of sealing failure. Further, the inclined surface structure can make the sealing ring deform better under pressure, adapt to different working conditions, and ensure the sealing performance under different conditions; (2) The stepped design can effectively promote the outward flow of the electrolyte, reduce the accumulation of liquid inside the sealing ring, and thus lower the leakage risk; (3) By improving the explosion-proof valve, a ring platform is protruded on the outer ring wall, and the ring platform is embedded with the ring groove, which can improve the sealing effect; (4) By filling the pole column encapsulation in the encapsulation gap, an effective seal can be formed to prevent the leakage of the electrolyte and the intrusion of external pollutants, thereby improving the safety and reliability of the battery. Moreover, the encapsulation material usually has good elasticity, which can provide a certain buffering effect when the pole column is subjected to external impact or vibration, protect the internal components, and reduce mechanical damage. Further, the pole column encapsulation can provide a layer of protection to prevent the direct contact between the pole column material and the electrolyte, reduce the risk of corrosion, and extend the service life of the pole column; (5) The explosion-proof valve of the present solution has a variety of material options, which can meet the requirements of economy and high working ability (such as high-temperature requirements); (6) The plastic part and the sealing ring of the present solution are integrally formed, reducing the seams and potential leakage points during the assembly process, and improving the overall sealing effect and structural strength; (7) Through the connecting piece, the connection between the sealing ring and the plastic part and between the explosion-proof valve and the plastic part is realized, enhancing the stability of the overall structure. Moreover, the split structure can optimize the heat dissipation and management, reduce the temperature of the battery components during operation, and improve the safety and service life of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art.

[0027] Figure 1 FIG. is a schematic structural diagram of a battery cover assembly that can improve airtightness according to an embodiment of the present application;

[0028] Figure 2 is Figure 1 A cross-sectional view of the battery cover assembly that can improve airtightness shown in FIG.

[0029] Figure 3 is Figure 2 An enlarged view of a schematic structural diagram of the sealing ring at position I in FIG.

[0030] Figure 4 FIG. is another schematic structural diagram of the sealing ring according to an embodiment of the present application;

[0031] Figure 5 is another structural schematic diagram of the explosion-proof valve according to an embodiment of the present application;

[0032] Figure 6 is Figure 1 the front view of the battery cover assembly capable of improving airtightness shown in the figure;

[0033] Figure 7 is Figure 1 the bottom view of the battery cover assembly capable of improving airtightness shown in the figure;

[0034] Figure 8 is Figure 1 the exploded view of the battery cover assembly capable of improving airtightness shown in the figure;

[0035] Figure 9 is another structural schematic diagram of the battery cover assembly capable of improving airtightness according to an embodiment of the present application;

[0036] Figure 10 is Figure 9 the sectional view of the battery cover assembly capable of improving airtightness shown in the figure;

[0037] Figure 11 is Figure 9 the exploded view of the battery cover assembly capable of improving airtightness shown in the figure;

[0038] Figure 12 is another structural schematic diagram of the battery cover assembly capable of improving airtightness according to an embodiment of the present application;

[0039] Figure 13 is Figure 12 the sectional view of the battery cover assembly capable of improving airtightness shown in the figure;

[0040] Figure 14 is Figure 12 the exploded view of the battery cover assembly capable of improving airtightness shown in the figure;

[0041] Figure 15 is another structural schematic diagram of the battery cover assembly capable of improving airtightness according to an embodiment of the present application;

[0042] Figure 16 is Figure 15 the sectional view of the battery cover assembly capable of improving airtightness shown in the figure;

[0043] Figure 17 is Figure 15 the exploded view of the battery cover assembly capable of improving airtightness shown in the figure;

[0044] In the figure, 1 is the cover plate body, 11 is the pole hole, 12 is the cover plate step, 13 is the annular groove, 14 is the explosion-proof hole, 2 is the pole column assembly, 21 is the pole column body, 211 is the column side wall, 212 is the groove, 213 is the top boss, 22 is the sealing ring, 220 is the inner wall, 221 is the outer wall, 222 is the step plane, 223 is the step connection surface, 224 is the transition connection surface, 225 is the first step, 2251 is the first step plane, 2252 is the first step connection surface, 226 is the second step, 2261 is the second step plane, 2262 is the second step connection surface, 227 is the annular platform, 23 is the pole column encapsulation with rubber, 3 is the pressing plate, 31 is the explosion-proof valve, 4 is the plastic part, 5 is the third connecting piece, and 6 is the fourth connecting piece. Detailed implementation mode

[0045] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0046] Specifically, according to one aspect of the present application, a battery cover plate assembly capable of improving airtightness is disclosed. Specifically, refer to Figures 1 to 8 As shown, the battery cover plate assembly includes a cover plate body 1 and a pole column assembly 2 assembled on the cover plate body 1. A pole hole 11 is provided on the cover plate body 1, and the pole column assembly 2 is assembled in cooperation with the pole hole 11. Among them, continue to refer to Figure 1 , Figure 2 , Figures 6 to 17 As shown, there are two sets of pole column assemblies 2, including a positive pole column assembly and a negative pole column assembly. The positive pole column assembly and the negative pole column assembly are symmetrically arranged at both ends of the cover plate body 1, and the composition and structure of the positive pole column assembly and the negative pole column assembly are the same. Exemplarily, since the composition and structure of the two sets of pole column assemblies 2 (the positive pole column assembly and the negative pole column assembly) are the same, the pole column assembly described in this solution is one of the pole column assemblies 1 that are not divided into positive and negative poles.

[0047] Furthermore, continue to refer to Figures 1 to 7The terminal post assembly 2 includes a terminal post body 21 and a sealing ring 22. The terminal post body 21 penetrates through the terminal post hole 11. After the terminal post body 21 penetrates through the terminal post hole 11, a sealing gap with a compression allowance is formed between the terminal post body 21 and the cover plate body 1. The sealing gap is filled by compressing the sealing ring 22. A cover plate step 12 is provided on the cover plate body 1 on one side of the sealing gap. The sealing ring 22 includes an inner wall 220 and an outer wall 221 spaced from the inner wall 220 by a target width. The inner wall 220 cooperates with the side wall 211 of the column body of the terminal post body 21. A gradient step and a transition connection surface 224 matching the cover plate step 12 are formed in the width direction of the sealing ring 22. The gradient step includes at least one step, and each step includes a step plane 222 and a step connection surface 223. The step plane 222 and the transition connection surface 224 or two adjacent step planes 222 are connected by a step connection surface 223. The inner wall 220 is an inclined plane and / or at least one of the step connection surfaces 223 in at least one step is an inclined plane. It can be understood that the sealing gap with a compression allowance means that the height of the sealing gap is smaller than the thickness of the sealing ring 22. When installing the sealing ring 22, the sealing ring is extruded into the sealing gap by compressing the sealing ring 22. Thus, after the sealing ring 22 is installed in the sealing gap, it elastically returns to its original position and fills the sealing gap, so that a tight seal can be achieved between the sealing ring 22 and the sealing gap.

[0048] Specifically, the sealing ring can be directly sleeved on the terminal post body 21 in the form of a single accessory, or can be directly injection-molded on the sealing gap. Before injection molding, glue can be applied to the cover plate step 12 of the cover plate body 1 first to improve the stability of the sealing ring after injection molding. Exemplarily, the glue application can be achieved by means of pad printing or brushing.

[0049] In one embodiment, as Figure 2 and Figure 3As shown, the gradient step includes two steps, namely the first step 225 and the second step 226. The first step 225 is arranged close to the inside of the sealing ring 22, and the second step 226 is arranged close to the outer wall of the sealing ring 22. The gradient step slopes downward from the inner wall 220 to the outer wall 221 in the target width direction, that is, the first step 225 is higher than the second step 226. The first step 225 includes a first step plane 2251 and a first step connecting surface 2252, and the second step 226 includes a second step plane 2261 and a second step connecting surface 2262. One side of the first step plane 2251 is connected to the top edge of the inner wall 220, the other side of the first step plane 2251 is connected to the first step connecting surface 2252, the other side of the first step connecting surface 2252 is connected to the second step plane 2261, the other side of the second step plane 2261 is connected to the second step connecting surface 2262, and the other side of the second step connecting surface 2262 is connected to the transition connecting surface 224. Among them, in this example, the inner wall 220 of the sealing ring 22, the first step connecting surface 2252, and the second step connecting surface 2262 are all inclined planes with the same inclination direction and the same or different inclination angles. It can be understood that in another implementation, the gradient step can also be arranged to slope upward from the inner wall 220 to the outer wall 221 in the target width direction.

[0050] In another embodiment, as Figure 4 shown, the gradient step only includes the first step 225. At this time, one side of the first step plane 2251 is connected to the top edge of the inner wall 220 of the sealing ring 22, the other side of the first step plane 2251 is connected to the first step connecting surface 2252, and the other end of the first step connecting surface 2252 is directly connected to the transition connecting surface 224. Among them, in this example, the inner wall 220 of the sealing ring 22 and the first step connecting surface 2252 are both inclined planes with the same inclination direction and the same or different inclination angles.

[0051] It can be understood that in the gradient step shown above Figure 3 the inner wall 220 of the sealing ring 22, the first step connecting surface 2252, and the second step connecting surface 2262 are all inclined planes, which is only a preferred implementation. In other feasible solutions, only one or two of the inner wall 220 of the sealing ring 22, the first step connecting surface 2252, or the second step connecting surface 2262 can be set as inclined planes, and the other one or two can be set as vertical planes, which can be specifically set based on actual needs. Similarly, in the gradient step shown above Figure 4 the inner wall 220 of the sealing ring 22 and the first step connecting surface 2252 being both inclined planes is also only a preferred implementation. In other feasible solutions, only one of the inner wall 220 of the sealing ring 22 or the first step connecting surface 2252 can be set as an inclined plane, and the other one can be set as a vertical plane, which can be specifically set based on actual needs.

[0052] It can be understood that the inclined surface design of the sealing ring 22 can increase the contact area between the sealing ring 22 and the pole column body 21, enabling the sealing ring 22 to fit more effectively on the surface of the pole column body 21, thereby enhancing the sealing performance. Moreover, the inclined surface design can make the pressure more evenly distributed on the contact surface of the sealing ring 22 when the sealing ring 22 is compressed, reducing the phenomenon of local stress concentration and lowering the risk of sealing failure. Further, the inclined surface structure can enable the sealing ring 22 to deform better under pressure, adapt to different working conditions, and ensure the sealing performance under different conditions. Further, the stepped design can effectively promote the outward flow of the electrolyte, reduce the accumulation of liquid inside the sealing ring 22, and thus reduce the leakage risk.

[0053] In some embodiments, continue to refer to Figure 1 、 Figure 2 、 Figures 6 to 17 , the pole column assembly 2 further includes a pole column encapsulation 23, and a encapsulation gap is formed between the pole column body 21 and the cover plate body 1 after the pole column body 21 penetrates through the pole column hole 11. In one example, a groove 212 is formed on the column side wall 211 of the pole column body 21, and the encapsulation gap is formed between the groove 212 and the cover plate body 1. The pole column encapsulation 23 is injection-molded to fill the groove 212 to realize that the pole column encapsulation 23 fills the encapsulation gap. Further, a top boss 213 is formed above the groove 212, and a bottom boss is formed below the groove 212, wherein the outer wall of the bottom boss is the column side wall 211 of the pole column body 21. Exemplarily, the pole column encapsulation 23 is fluororubber or EPDM or TPV. It can be understood that by filling the pole column encapsulation 23 in the encapsulation gap, an effective seal can be formed to prevent the leakage of the electrolyte and the intrusion of external pollutants, thereby improving the safety and reliability of the battery. Moreover, the encapsulation material usually has good elasticity and can provide a certain buffering effect when the pole column is subjected to external impact or vibration, protecting the internal components and reducing mechanical damage. Further, the pole column encapsulation 23 can provide a layer of protection to prevent the direct contact between the pole column material and the electrolyte, reduce the risk of corrosion, and extend the service life of the pole column.

[0054] In some embodiments, the battery cover plate assembly further includes an explosion-proof component located on the cover plate body 1. The explosion-proof valve 31 of the explosion-proof component cooperates with the explosion-proof hole 14 opened on the cover plate body 1. The materials of the sealing ring 22 and the explosion-proof valve 31 are both rubber materials. In one example, the material of the explosion-proof valve 31 can be EPDM or TPV or fluororubber material. EPDM and fluororubber have excellent tolerance to various chemical substances (such as acids, alkalis, and electrolytes), can effectively prevent material degradation, and extend the service life of the explosion-proof component. Fluororubber can withstand higher temperatures, is suitable for use in high-temperature environments, reduces the probability of failure due to high temperature during battery operation. Moreover, TPV and EPDM have good elasticity, can maintain good sealing performance under extreme conditions, prevent gas or liquid leakage, and ensure the safety of the battery. TPV and EPDM materials are easy to process and form, can manufacture complex explosion-proof components according to design requirements, and meet different application needs. In this embodiment, the explosion-proof valve 31 has a variety of material choices, which can meet economic and high working ability requirements (such as high-temperature requirements).

[0055] Further, in one embodiment, as Figure 5 shown, the explosion-proof valve 31 includes an outer ring wall, and a ring platform 227 protrudes outward from the outer ring wall. A ring groove 13 is opened on the cover plate body 1, and the ring platform 227 is arranged in the ring groove 13. The explosion-proof component further includes a pressing plate 3. After the ring platform 227 is arranged in the ring groove, the pressing plate 3 presses on the other side of the ring platform 227. Among them, the pressing plate 3 is welded to the cover plate body 1. Exemplarily, as Figure 5 shown in a, the pressing plate 1 can be arranged on the top surface of the cover plate body 1 to realize the pressing of the pressing plate 3 on the explosion-proof valve 31. Further, as Figure 5 shown in b, the pressing plate 1 can also be arranged on the bottom surface of the cover plate body 1. It can be understood that, since the space on the bottom surface of the cover plate body 1 is relatively large, it is preferable to arrange the pressing plate 1 on the bottom surface of the cover plate body 1, so as to increase the area of the pressing plate 3, thereby improving the pressing force on the explosion-proof valve 31 and improving the sealing performance. In this example, the thickness of the explosion-proof valve can be 0.08 mm to 0.15 mm, and the explosion-proof pressure it can withstand is 0.133 Mpa to 0.643 Mpa.

[0056] Further, in some embodiments, a battery cell cover plate is provided above the terminal assembly. A conductive material is coated on the top surface of the explosion-proof valve 31. When the explosion-proof valve 31 bulges upward due to air pressure to a first target height, the conductive material contacts the circuit contact on the battery cell cover plate, and the working data of the battery cell is read, so that the battery management system determines the abnormal battery cell through the working data. Specifically, after the conductive material contacts the circuit contact on the battery cell cover plate, the circuit is connected. At this time, the battery management system can monitor and read the working data of the battery cell under the current path through this path circuit, so as to determine whether the battery cell is working normally based on the working data. Among them, the working data at least includes the battery cell temperature. In one example, if the battery cell temperature increases sharply in a short time, it indicates that the battery cell has an explosion risk, and at this time, the battery cell is determined to be an abnormal battery cell. Further, after determining the abnormal battery cell, an alarm device can be used to give an alarm to achieve timely warning.

[0057] It can be understood that by coating a conductive material on the top surface of the explosion-proof valve 31 and making the explosion-proof valve 31 bulge upward when it is subjected to gas pressure, when it bulges to a certain height, the conductive coating contacts the circuit contact on the battery cell cover plate, so that the explosion risk monitoring of the battery cell can be realized, thereby improving the safety of battery application.

[0058] In some embodiments, a puncture pin is further provided above the explosion-proof valve. The puncture pin is located above the battery cell cover plate. When the explosion-proof valve bulges due to air pressure to a second target height, it is punctured by the puncture pin to relieve pressure, and the second target height is higher than the first target height. It can be understood that by providing a puncture pin above the explosion-proof valve 31, a two-stage protection mechanism is realized, and this two-stage protection mechanism can more effectively prevent the battery from overheating or exploding and improve the safety of the battery.

[0059] In some embodiments, the size of the explosion-proof valve is determined based on the pressure storage requirement. It can be understood that when the explosion-proof valve 31 is applied to a solid-state electrode, due to the limited space inside the battery cell housing, when the bulge of the explosion-proof valve 31 is relatively small, an explosion may be caused. Therefore, in this solution, the size of the explosion-proof valve 31 in each battery cover plate assembly is determined by the pressure storage requirement, so that the explosion-proof requirement of different battery cells can be achieved by the explosion-proof valve 31. Preferably, the size of the explosion-proof valve 31 can also be set to be larger. This design with a larger size can increase the pressure storage volume of the explosion-proof valve and reduce the explosion risk of the explosion-proof valve.

[0060] Further, the battery cover plate assembly further includes a plastic part 4, and the plastic part 4 supports at the bottom of the cover plate body 1.

[0061] In some embodiments, continue to refer to Figure 2 、 Figure 7 and Figure 8As shown, the plastic part 4 is arranged around the pole column assembly 2. The plastic part 4 includes a plurality of abutting parts. One of the plurality of abutting parts abuts below the sealing ring 22, one abuts against the bottom of the cover plate body 1, and one abuts against the column side wall 211 of the pole column body 21. Both the plastic part 4 and the sealing ring 22 are made of fluororubber. The plastic part 4 and the sealing ring 22 are integrally formed. The explosion-proof valve 31 is made of EPDM material. In this example, the plastic part 4 and the sealing ring 22 are integrally formed, reducing the seams and potential leakage points in the assembly process, improving the overall sealing effect and structural strength. The EPDM material reduces costs while ensuring the explosion-proof effect.

[0062] In some embodiments, as Figures 9 to 11 As shown, the plastic part 4 is arranged around the pole column assembly 2. The plastic part 4 includes a plurality of abutting parts. One of the plurality of abutting parts abuts below the sealing ring 22, one abuts against the bottom of the cover plate body 1, and one abuts against the column side wall 211 of the pole column body 21. Both the plastic part 4 and the sealing ring 22 are made of fluororubber. The plastic part 4 and the sealing ring 22 are separately formed. The plastic part 4 is made of silicone rubber, the sealing ring 22 is made of fluororubber, and the explosion-proof valve 31 is made of EPDM material. Or, both the plastic part 4 and the sealing ring 22 are made of fluororubber, and the explosion-proof valve 31 is made of EPDM material.

[0063] In some embodiments, as Figures 12 to 14 As shown, the plastic part 4 integrally surrounds the pole column assembly 2 (positive pole column assembly and negative pole column assembly) and the explosion-proof valve 31. Both the plastic part 4, the sealing ring 22 and the explosion-proof valve 31 are made of EPDM material, and the plastic part 4, the sealing ring 22 and the explosion-proof valve 31 are integrally formed. Integrally forming the plastic part 4, the sealing ring 22 and the explosion-proof valve 31 can reduce the processing procedures and improve the processing efficiency. Further, it reduces the seams and potential leakage points in the assembly process, improves the overall sealing effect and structural strength. Moreover, both the plastic part 4, the sealing ring 22 and the explosion-proof valve 31 are made of EPDM material. This material has good tolerance to a variety of chemical substances and high temperature resistance, can resist the influence of electrolyte and other corrosive substances, extend the service life of the component, and can reduce costs.

[0064] In some embodiments, as Figures 15 to 17As shown, a first connecting member and a second connecting member are provided on the plastic part 4, a third connecting member 5 is formed on the sealing ring 22, and a fourth connecting member 6 is provided on the explosion-proof valve 31. After the first connecting member cooperates with the third connecting member 5 and the second connecting member cooperates with the fourth connecting member 6, the plastic part 4 is integrally installed around the pole assembly 2 and the explosion-proof valve 31. The plastic part 4 is made of EPDM or TPV material, the third connecting member 5 and the sealing ring 22 are both made of fluororubber material, and the third connecting member 5 and the sealing ring 22 are integrally formed. At this time, the sealing ring 22 is only located at the pole assembly 2. The fourth connecting member 6 and the explosion-proof valve 31 are both made of EPDM material, and the fourth connecting member 6 and the explosion-proof valve 31 are integrally formed. The connection between the sealing ring 22 and the plastic part 4 and between the explosion-proof valve 31 and the plastic part 4 is realized through the connecting members, which enhances the stability of the overall structure, and the split structure can optimize the heat dispersion and management, reduce the temperature of the battery assembly during operation, and improve the safety and service life of the battery.

[0065] In some embodiments, a first connecting member and a second connecting member are provided on the plastic part 4, a third connecting member 5 is formed on the sealing ring 22, and a fourth connecting member 6 is provided on the explosion-proof valve 31. After the first connecting member cooperates with the third connecting member 5 and the second connecting member cooperates with the fourth connecting member 6, the plastic part 4 is integrally installed around the pole assembly 2 and the explosion-proof valve 31. The sealing ring 22 is integrally injection-molded. In this example, the sealing ring 22 is integrally arranged around the pole assembly 2 and the explosion-proof valve 31, that is, while the sealing ring 22 surrounds the pole assembly 2, it is integrally formed with the explosion-proof valve 31 (the overall formed structure is not shown separately, and the rest of the structural relationships refer to Figures 15 to 17 ), and both the sealing ring 22 and the explosion-proof valve 31 are made of EPDM material. The connection between the sealing ring 22 and the plastic part 4 and between the explosion-proof valve 31 and the plastic part 4 is realized through the connecting members, which enhances the stability of the overall structure, and the split structure can optimize the heat dispersion and management, reduce the temperature of the battery assembly during operation, and improve the safety and service life of the battery.

[0066] According to another aspect of the present application, a power battery is also disclosed, and the power battery includes the battery cover assembly capable of improving airtightness as described in any one of the above.

[0067] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed.

Claims

1. A battery cover assembly capable of improving airtightness, characterized in that: The battery cover plate assembly comprises a cover plate body (1), a pole assembly (2) assembled on the cover plate body (1), and a plastic part (4) supported on the bottom of the cover plate body (1); the cover plate body (1) is provided with a pole hole (11); the pole assembly (2) is assembled with the pole hole (11); the pole assembly (2) comprises a pole body (21) and a sealing ring (22); the pole body (21) passes through the pole hole (11); after the pole body (21) passes through the pole hole (11), a sealing gap with a compression margin is formed between the pole body (21) and the cover plate body (1); the sealing gap is filled by compressing the sealing ring (22); a cover plate step (12) is provided on the cover plate body (1) on one side of the sealing gap; the sealing ring (22) includes a The invention relates to a sealing ring (220) comprising an inner wall (220) and an outer wall (221) spaced apart from the inner wall (220) by a target width, wherein the inner wall (220) cooperates with the column side wall (211) of the pole column (21), and a gradient step and a transition connection surface (224) matching the cover plate step (12) are formed on the sealing ring (22) in the target width direction, wherein the gradient step comprises at least one step, and each of the steps comprises a step plane (222) and a step connection surface (223), and the step plane (222) and the transition connection surface (224) or two adjacent step planes (222) are connected by a step connection surface (224), and the inner wall (220) is an inclined surface and / or at least one step connection surface (223) of at least one of the steps is an inclined surface.

2. The battery cover assembly capable of improving airtightness according to claim 1, characterized in that: The battery cover assembly also includes an explosion-proof valve (31) that cooperates with the explosion-proof hole (14) opened on the cover body (1), and the sealing ring (22) and the explosion-proof valve (31) are both made of rubber.

3. The battery cover assembly capable of improving airtightness according to claim 2, characterized in that: The explosion-proof valve (31) is made of EDPM, TPV or fluororubber.

4. The battery cover assembly capable of improving airtightness according to claim 3, characterized in that: The explosion-proof valve (31) comprises an outer ring wall, on which a ring platform (227) protrudes outwards, and the cover plate body (1) is provided with a ring groove (13), in which the ring platform (227) is arranged, and the explosion-proof component also comprises a clamping plate (3), after the ring platform (227) is embedded in the ring groove (13), the clamping plate (3) clamps the other side of the ring platform (227), and the clamping plate (3) is welded to the cover plate body (1).

5. The battery cover assembly capable of improving airtightness according to claim 4, characterized in that: A cell cover is provided above the pole assembly (2), and a top surface of the explosion-proof valve (31) is coated with a conductive material. When the explosion-proof valve (31) is raised to a first target height by air pressure, the conductive material contacts the circuit contacts on the cell cover, and the working data of the cell is read, so that the battery management system determines the abnormal cell through the working data, wherein the working data at least includes the cell temperature.

6. The battery cover assembly capable of improving airtightness according to claim 4 or 5, characterized in that: A puncture needle is also provided above the explosion-proof valve (31), and the puncture needle is located above the battery cover plate. When the explosion-proof valve (31) is bulged to a second target height due to air pressure, it is punctured by the puncture needle to release pressure, and the second target height is higher than the first target height.

7. The battery cover assembly capable of improving airtightness according to claim 4 or 5, characterized in that: The size of the explosion-proof valve (31) is determined based on the pressure storage requirement.

8. The battery cover assembly capable of improving airtightness according to claim 2, characterized in that: The plastic part (4) is arranged around the pole assembly (2), and the plastic part (4) includes a plurality of abutting portions, one of which abuts below the sealing ring (22), one of which abuts the bottom of the cover plate body (1), and one of which abuts against the column side wall (211) of the pole body (21).

9. The battery cover assembly capable of improving airtightness according to claim 8, characterized in that: The plastic part (4) and the sealing ring (22) are both made of fluororubber, the plastic part (4) and the sealing ring (22) are integrally formed, and the explosion-proof valve (31) is made of EPDM.

10. The battery cover assembly capable of improving airtightness according to claim 8, characterized in that: The plastic part (4) and the sealing ring (22) are both made of fluororubber, and the explosion-proof valve is made of EPDM.

11. The battery cover assembly capable of improving airtightness according to claim 2, characterized in that: The plastic part (4) is integrally arranged around the pole assembly (2) and the explosion-proof valve (31); the plastic part (4), the sealing ring (22) and the explosion-proof valve (31) are all made of EPDM material; the plastic part (4), the sealing ring (22) and the explosion-proof valve (31) are integrally formed.

12. The battery cover assembly capable of improving airtightness according to claim 2, characterized in that: The plastic part (4) is provided with a first connecting part and a second connecting part, the sealing ring (22) is formed with a third connecting part (5), and the explosion-proof valve (31) is provided with a fourth connecting part (6). The first connecting part cooperates with the third connecting part, and the second connecting part cooperates with the fourth connecting part (6), so that the plastic part (4) is integrally installed around the pole assembly (2) and the explosion-proof valve (31).

13. The battery cover assembly capable of improving airtightness according to claim 12, characterized in that: The plastic part (4) is made of EPDM or TPV material, the third connecting part (5) and the sealing ring (22) are both made of fluororubber material, the third connecting part (5) and the sealing ring (22) are integrally formed, the fourth connecting part (6) and the explosion-proof valve (31) are both made of EPDM material, and the fourth connecting part (6) and the explosion-proof valve (31) are integrally formed.

14. The battery cover assembly capable of improving airtightness according to claim 12, characterized in that: The sealing ring (22) is formed by integral injection molding, and the sealing ring (22) is integrally arranged around the pole assembly (2) and the explosion-proof valve (31), and the sealing ring (22) and the explosion-proof valve (31) are both made of EPDM material. 15 . A power battery, comprising the battery cover assembly capable of improving airtightness according to any one of claims 1 to 14 .

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