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

Abstract

The utility model discloses a battery cover plate component capable of improving air tightness, which comprises a cover plate body and a pole component assembled on the cover plate body, the pole component comprises a pole body and a sealing ring, the pole body penetrates through a pole hole on the cover plate body, the sealing ring is filled between the pole body and the pole hole, and a cover plate step is arranged on the cover plate body; 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] This utility model belongs to the field of battery equipment technology, specifically relating to a battery cover assembly and a power battery that can improve airtightness. Background Technology

[0002] Electricity, as a clean energy source, is increasingly widely used. As a device that stores electricity, the safety of batteries is paramount. Therefore, the battery terminals on the battery cover need to be sealed with sealing rings to prevent the leakage of electrolyte or other chemicals from the battery, which could damage the environment or pose safety hazards to the equipment. It also helps prevent external moisture or dust from entering the battery and affecting its performance.

[0003] Currently, traditional battery cover assemblies, such as the solution disclosed in publication number CN221783324U, use a traditional annular sealing ring. While simple in design, this often leads to acid seepage at the contact points between the sealing ring and the terminals, and between the sealing ring and the battery cover during subsequent battery use. Furthermore, prolonged vibrations during battery use can cause the seal to weaken. These issues affect battery lifespan and cause unnecessary inconvenience for users. Therefore, improving the sealing effect of the terminals is an urgent problem to be solved. Utility Model Content

[0004] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a battery cover assembly and power battery that can improve airtightness, and solve the problem of poor terminal sealing effect in the prior art.

[0005] According to one aspect of this application, a battery cover assembly with improved airtightness is disclosed. The battery cover assembly includes a cover body and an electrode post assembly mounted on the cover body. The cover body has an electrode post hole, and the electrode post assembly is fitted into the electrode post hole. The electrode post assembly includes an electrode post body and a sealing ring. The electrode post body penetrates through the electrode post hole, and a sealing gap with compression allowance is formed between the electrode post body and the cover body after penetrating the electrode post hole. The sealing gap is filled by compressing the sealing ring. A [feature / feature] is provided on one side of the cover body of the sealing gap. The cover plate step; the sealing ring includes an inner wall and an outer wall spaced apart from the inner wall by a target width, the inner wall mates with the column sidewall of the pole body, and the sealing ring has a gradient step and a transition connection surface that match the cover plate step in the target width direction, the gradient step includes at least one step, each step includes a step plane and a step connection surface, the step plane and the transition connection surface or two adjacent step planes are connected by a step connection surface, the inner wall is an inclined surface and / or at least one of the step connection surfaces is an inclined surface.

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

[0007] In some embodiments, the pole post assembly further comprises a pole post encapsulation, a gap is formed between the pole post and the cover plate body after the pole post passes through the pole post hole, and the gap is filled by the pole post encapsulation.

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

[0009] In some embodiments, the battery cover plate assembly further comprises an explosion-proof assembly on the cover plate body, the explosion-proof assembly comprises an explosion-proof valve matched with an explosion-proof hole formed on the cover plate body, and the sealing ring and the explosion-proof valve are 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 comprises an outer ring wall, an annular table is protruded outwardly on the outer ring wall, an annular groove is formed on the cover plate body, the annular table is arranged in the annular groove, the explosion-proof assembly further comprises a pressing plate, the annular table is arranged in the annular groove, the pressing plate presses the other side of the annular table, and the pressing plate is welded with 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, an electric core cover plate is arranged above the pole post assembly, a top surface of the explosion-proof valve is coated with a conductive material, when the explosion-proof valve is protruded to a first target height by air pressure, the conductive material contacts a circuit contact on the electric core cover plate, working data of the electric core is read, so that the battery management system determines an abnormal electric core based on the working data, and the working data at least comprises the temperature of the electric core.

[0014] In some embodiments, a piercing needle is further arranged above the explosion-proof valve, the piercing needle is located above the electric core cover plate, when the explosion-proof valve is protruded to a second target height by air pressure, the explosion-proof valve is pierced by the piercing needle 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 comprises a plastic part, and the plastic part is supported on the bottom of the cover plate body.

[0017] In some embodiments, the plastic member is arranged around the pole assembly, the plastic member comprises a plurality of abutting portions, one of the plurality of abutting portions is arranged below the sealing ring, one of the plurality of abutting portions is arranged at the bottom of the cover body, and one of the plurality of abutting portions is arranged in abutment with the pole side wall of the pole body.

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

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

[0020] In some embodiments, the plastic member is integrally arranged around the pole assembly and the explosion-proof valve, the plastic member, the sealing ring, and the explosion-proof valve are made of EPDM material, and the plastic member, the sealing ring, and the explosion-proof valve are integrally formed.

[0021] In some embodiments, the plastic member is provided with a first connecting member and a second connecting member, the sealing ring is formed with a third connecting member, the explosion-proof valve is provided with a fourth connecting member, and the first connecting member and the third connecting member are matched with each other, and the second connecting member and the fourth connecting member are matched with each other, so that the plastic member is integrally arranged around the pole assembly and the explosion-proof valve.

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

[0023] In some embodiments, the sealing ring is integrally formed by injection molding, the sealing ring is integrally arranged around the pole assembly and the explosion-proof valve, and the sealing ring and the explosion-proof valve are made of EPDM material.

[0024] According to another aspect of the present application, a power battery is also disclosed, which comprises the battery cover plate assembly with improved air tightness as any one of the above.

[0025] The scheme 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 body, so that the sealing ring can be more effectively fitted on the surface of the pole body, thereby enhancing the sealing performance, and 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 local stress concentration phenomenon and the risk of sealing failure, further, the inclined surface structure can make the sealing ring deform better when being pressed, adapt to different working conditions and ensure the sealing performance under different conditions; (2) the stepped design can effectively promote the outward flow of electrolyte and reduce the accumulation of liquid in the sealing ring, thereby reducing the risk of leakage; (3) through the improvement of the explosion-proof valve, the ring table is protruded on the outer ring wall, and the ring table and the ring groove are embedded, which can improve the sealing effect; (4) by filling the pole encapsulation in the encapsulation gap, an effective seal can be formed to prevent electrolyte leakage and the invasion of external contaminants, thereby improving the safety and reliability of the battery, and the encapsulation material usually has good elasticity, which can provide a certain buffering effect when the pole is subjected to external impact or vibration, protect the internal components and reduce mechanical damage, further, the pole encapsulation can provide a layer of protection to prevent the pole material from directly contacting the electrolyte, reduce the risk of corrosion and prolong the service life of the pole; (5) the explosion-proof valve of the scheme has multiple material options, which can meet the economic and high working capacity requirements (such as high temperature requirements); (6) the plastic part and the sealing ring of the scheme are integrally formed, which reduces the joints and potential leakage points in the assembly process, improves the overall sealing effect and structural strength; (7) the connection between the sealing ring and the plastic part and the connection between the explosion-proof valve and the plastic part are realized through the connecting piece, which enhances the stability of the overall structure, and the split structure can optimize heat dispersion and management, reduce the temperature of the battery assembly during operation and improve the safety and service life of the battery. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description.

[0027] Figure 1 is a structure diagram of a battery cover plate assembly capable of improving air tightness according to an embodiment of the present application;

[0028] Figure 2 is Figure 1 is a sectional view of the battery cover plate assembly capable of improving air tightness shown in the figure;

[0029] Figure 3 is an enlarged view of the structure diagram of the sealing ring at I of Figure 2

[0030] Figure 4 is another structure diagram of the sealing ring according to an embodiment of the present application;​

[0031] Figure 5 a、5b is another structural schematic view of the explosion-proof valve of the embodiment of the present application;

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

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

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

[0035] Figure 9 is another structural schematic view of the battery cover plate assembly capable of improving air tightness of the embodiment of the present application;

[0036] Figure 10 is Figure 9 the cross-sectional view of the battery cover plate assembly capable of improving air tightness shown in the figure;

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

[0038] Figure 12 is another structural schematic view of the battery cover plate assembly capable of improving air tightness of the embodiment of the present application;

[0039] Figure 13 is Figure 12 the cross-sectional view of the battery cover plate assembly capable of improving air tightness shown in the figure;

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

[0041] Figure 15 is another structural schematic view of the battery cover plate assembly capable of improving air tightness of the embodiment of the present application;

[0042] Figure 16 is Figure 15 the cross-sectional view of the battery cover plate assembly capable of improving air tightness shown in the figure;

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

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

[0045] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the utility model.

[0046] Specifically, according to one aspect of the present application, a battery cover plate assembly capable of improving air tightness is disclosed. Specifically, referring to Figures 1 to 8 As shown, the battery cover plate assembly comprises a cover plate body 1 and a pole assembly 2 assembled on the cover plate body 1, and the cover plate body 1 is provided with a pole hole 11, and the pole assembly 2 is assembled in cooperation with the pole hole 11. Wherein, referring to Figure 1 、 Figure 2 、 Figures 6 to 17 As shown, the pole assembly 2 is two groups, including a positive pole assembly and a negative pole assembly, and the positive pole assembly and the negative pole assembly are symmetrically arranged at both ends of the cover plate body 1, and the positive pole assembly and the negative pole assembly are the same in composition and structure. Exemplarily, since the two groups of pole assemblies 2 (positive pole assembly and negative pole assembly) are the same in composition and structure, the pole assembly introduced in the present scheme is one group of pole assembly 1 without positive and negative poles.

[0047] Further, referring to Figures 1 to 7The pole post assembly 2 comprises a pole post body 21 and a sealing ring 22, the pole post body 21 penetrates through the pole post hole 11, and a sealing gap with a compression allowance is formed between the pole post body 21 and the cover plate body 1 after the pole post body 21 penetrates through the pole post hole 11, the sealing gap is filled after the compression sealing ring 22 is compressed, and the cover plate body 1 on one side of the sealing gap is provided with a cover plate step 12; the sealing ring 22 comprises 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 post side wall 211 of the pole post body 21, a gradient step and a transition connecting surface 224 matched with the cover plate step 12 are formed in the width direction of the sealing ring 22, the gradient step comprises at least one step, each step comprises a step plane 222 and a step connecting surface 223, the step plane 222 and the transition connecting surface 224 or the step planes 222 of two adjacent steps are connected by a step connecting surface 224, and the inner wall 220 is a slope and / or at least one step connecting surface 223 in at least one step is a slope. It can be understood that the sealing gap with a compression allowance refers to that the height of the sealing gap is smaller than the thickness of the sealing ring 22, and when the sealing ring 22 is installed, the sealing ring is extruded into the sealing gap by compressing the sealing ring 22, so that the sealing ring 22 is elastically reset after being installed into the sealing gap, the sealing gap is filled, and the sealing ring 22 and the sealing gap can be tightly sealed.

[0048] Specifically, the sealing ring can be directly sleeved on the pole post body 21 in the form of a fitting, and can also be directly injection molded on the sealing gap, and before injection molding, glue can be applied on the cover plate step 12 of the cover plate body 1 to improve the stability of the sealing ring after injection molding, for example, the glue application can be realized by pad printing or brushing.

[0049] In an embodiment, as Figure 2 and Figure 3As shown, the gradient steps include two steps, a first step 225 and a second step 226, the first step 225 is arranged close to the inner wall of the sealing ring 22, and the second step 226 is arranged close to the outer wall of the sealing ring 22, the gradient steps are arranged downhill from the inner wall 220 to the outer wall 221 along 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, 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 with the top side of the inner wall 220, the other side of the first step plane 2251 is connected with the first step connecting surface 2252, the other side of the first step connecting surface 2252 is connected with the second step plane 2261, the other side of the second step plane 2261 is connected with the second step connecting surface 2262, and the other side of the second step connecting surface 2262 is connected with the transition connecting surface 224. 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 surfaces, and have the same inclination direction and the same or different inclination angles. It can be understood that in another embodiment, the gradient steps can also be arranged uphill from the inner wall 220 to the outer wall 221 along the target width direction.

[0050] In another embodiment, as shown in FIG. 6, the gradient steps include only the first step 225, at this time, one side of the first step plane 2251 is connected with the top side of the inner wall 220 of the sealing ring 22, the other side of the first step plane 2251 is connected with the first step connecting surface 2252, and the other end of the first step connecting surface 2252 is directly connected with the transition connecting surface 224. In this example, the inner wall 220 of the sealing ring 22 and the first step connecting surface 2252 are both inclined surfaces, and have the same inclination direction and the same or different inclination angles. Figure 4 It can be understood that in the gradient steps shown above, 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 surfaces, which is only a preferred embodiment, and in other implementable embodiments, only one or two of the inner wall 220 of the sealing ring 22 or the first step connecting surface 2252 or the second step connecting surface 2262 can be arranged as an inclined surface, and the other one or two can be arranged as a vertical surface, which can be set based on actual needs. Similarly, in the gradient steps shown above, the inner wall 220 of the sealing ring 22 and the first step connecting surface 2252 are both inclined surfaces, which is also only a preferred embodiment, and in other implementable embodiments, only one of the inner wall 220 of the sealing ring 22 or the first step connecting surface 2252 can be arranged as an inclined surface, and the other one can be arranged as a vertical surface, which can be set based on actual needs.

[0051] Figure 3 It can be understood that in the gradient steps shown above, 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 surfaces, which is only a preferred embodiment, and in other implementable embodiments, only one or two of the inner wall 220 of the sealing ring 22 or the first step connecting surface 2252 or the second step connecting surface 2262 can be arranged as an inclined surface, and the other one or two can be arranged as a vertical surface, which can be set based on actual needs. Similarly, in the gradient steps shown above, the inner wall 220 of the sealing ring 22 and the first step connecting surface 2252 are both inclined surfaces, which is also only a preferred embodiment, and in other implementable embodiments, only one of the inner wall 220 of the sealing ring 22 or the first step connecting surface 2252 can be arranged as an inclined surface, and the other one can be arranged as a vertical surface, which can be set based on actual needs. Figure 4 It can be understood that in the gradient steps shown above, 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 surfaces, which is only a preferred embodiment, and in other implementable embodiments, only one or two of the inner wall 220 of the sealing ring 22 or the first step connecting surface 2252 or the second step connecting surface 2262 can be arranged as an inclined surface, and the other one or two can be arranged as a vertical surface, which can be set based on actual needs. Similarly, in the gradient steps shown above, the inner wall 220 of the sealing ring 22 and the first step connecting surface 2252 are both inclined surfaces, which is also only a preferred embodiment, and in other implementable embodiments, only one of the inner wall 220 of the sealing ring 22 or the first step connecting surface 2252 can be arranged as an inclined surface, and the other one can be arranged as a vertical surface, which can be 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 body 21, so that the sealing ring 22 can be more effectively fitted on the surface of the pole body 21, thereby enhancing the sealing performance, and the inclined surface design can make the pressure of the sealing ring 22 more evenly distributed on the contact surface of the sealing ring 22 when compressed, reducing the risk of local stress concentration and reducing the risk of sealing failure. Further, the inclined surface structure can make the sealing ring 22 deform better when 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 electrolyte and reduce the accumulation of liquid in the sealing ring 22, thereby reducing the risk of leakage.

[0053] In some embodiments, continuing to refer to Figure 1 , Figure 2 , Figures 6 to 17 , the pole assembly 2 further comprises a pole encapsulation 23, and the pole body 21 and the cover plate body 1 form an encapsulation gap after the pole body 21 penetrates the pole hole 11. In an example, a groove 212 is formed on the pole body side wall 211 of the pole body 21, and the groove 212 and the cover plate body 1 form the encapsulation gap. The pole encapsulation 23 is injection molded to fill the groove 212, so as to fill the encapsulation gap with the pole encapsulation 23. Further, a top boss 213 is formed above the groove 212, and a bottom boss is formed below the groove 212, wherein the outer boss wall of the bottom boss is the pole body side wall 211 of the pole body 21. In an example, the pole encapsulation 23 is fluororubber or EPDM or TPV. It can be understood that by filling the encapsulation gap with the pole encapsulation 23, an effective seal can be formed to prevent electrolyte leakage and external contaminants from entering, thereby improving the safety and reliability of the battery. Further, the encapsulation material generally has good elasticity and can provide a certain buffering effect when the pole is subjected to external impact or vibration, protecting the internal components and reducing mechanical damage. Further, the pole encapsulation 23 can provide a layer of protection to prevent direct contact between the pole material and the electrolyte, reducing the risk of corrosion and prolonging the service life of the pole.

[0054] In some embodiments, the battery cover plate assembly further comprises an explosion-proof assembly located on the cover plate body 1, the explosion-proof valve 31 of the explosion-proof assembly is matched with the explosion-proof hole 14 opened on the cover plate body 1, and the materials of the sealing ring 22 and the explosion-proof valve 31 are rubber materials. In an example, the material of the explosion-proof valve 31 can be EDPM or TPV or fluororubber material. EDPM and fluororubber have excellent resistance to various chemicals (such as acid, alkali and electrolyte), can effectively prevent material degradation, prolong the service life of the explosion-proof assembly, fluororubber can withstand high temperature, is suitable for use in high temperature environment, reduces the probability of failure due to high temperature when the battery is working, and TPV and EDPM 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 EDPM materials are easy to process and form, can manufacture complex explosion-proof assemblies according to design requirements, and meet different application requirements. In this embodiment, the explosion-proof valve 31 has multiple material options, which can meet economic and high working capacity requirements (such as high temperature requirements).

[0055] Further, in an embodiment, as shown in Figure 5 The explosion-proof valve 31 comprises an outer ring wall, the outer ring wall has a ring table 227 protruding outward, the cover plate body 1 has a ring groove 13, the ring table 227 is arranged in the ring groove 13, and the explosion-proof assembly further comprises a pressing plate 3. The ring table 227 is arranged behind the ring groove, and the pressing plate 3 is pressed on the other side of the ring table 227. The pressing plate 3 is welded to the cover plate body 1. As shown in Figure 5 a, the pressing plate 1 can be arranged on the top surface of the cover plate body 1 to press the explosion-proof valve 31. Further, as shown in Figure 5 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 bottom surface of the cover plate body 1 has relatively large space, the pressing plate 1 can be preferentially arranged on the bottom surface of the cover plate body 1, so as to increase the area of the pressing plate 3 and improve the pressing force of the explosion-proof valve 31 and the sealing performance. In this example, the thickness of the explosion-proof valve can be 0.08mm-0.15mm, and the withstand explosion-proof pressure can be 0.133Mpa-0.643Mpa.

[0056] Furthermore, in some embodiments, a cell cover plate is provided above the electrode assembly, and the top surface of the explosion-proof valve 31 is coated with a conductive material. When the explosion-proof valve 31 bulges to a first target height under air pressure, the conductive material contacts the circuit contacts on the cell cover plate, and the cell's operating data is read, allowing the battery management system to identify abnormal cells based on this data. Specifically, after the conductive material contacts the circuit contacts on the cell cover plate, the circuit is connected. At this time, the battery management system can monitor and read the cell's operating data under the current circuit path, thereby determining whether the cell is currently operating normally based on this data. The operating data includes at least the cell temperature. In one example, if the cell temperature increases sharply in a short period of time, it indicates that the cell has an explosion risk, and the cell is identified as abnormal. Furthermore, after identifying an abnormal cell, an alarm device can be used to issue an alarm for timely warning.

[0057] It is understandable that by coating the top surface of the explosion-proof valve 31 with conductive material and making the valve 31 bulge upward when subjected to gas pressure, the conductive coating contacts the circuit contacts on the cell cover when it bulges to a certain height. This enables monitoring of the cell's explosion risk, thereby improving the safety of battery applications.

[0058] In some embodiments, a puncture needle is also provided above the explosion-proof valve. The puncture needle is located above the cell cover plate. When the explosion-proof valve bulges to a second target height under air pressure, it is punctured by the puncture needle to release pressure. The second target height is higher than the first target height. It can be understood that by providing a puncture needle above the explosion-proof valve 31, a secondary protection mechanism is achieved. This secondary protection mechanism can more effectively prevent the battery from overheating or exploding, thereby improving battery safety.

[0059] In some embodiments, the size of the explosion-proof valve is determined based on the pressure storage requirement. It is understood that when the explosion-proof valve 31 is applied to solid-state electrodes, due to the limited space inside the cell housing, a small protrusion of the explosion-proof valve 31 could potentially cause an explosion. Therefore, in this solution, the size of the explosion-proof valve 31 in each battery cover assembly is determined by the pressure storage requirement, thereby achieving the explosion-proof requirements of the explosion-proof valve 31 for different cells. Preferably, the size of the explosion-proof valve 31 can also be set to be larger. This larger design can increase the pressure storage volume of the explosion-proof valve and reduce the risk of explosion.

[0060] Furthermore, the battery cover assembly also includes a plastic part 4, which is supported at the bottom of the cover body 1.

[0061] In some embodiments, continue reading Figure 2 , Figure 7 and Figure 8As shown, the plastic component 4 surrounds the pole assembly 2. The plastic component 4 includes multiple abutment portions, one of which abuts against the lower part of the sealing ring 22, another abuts against the bottom of the cover plate body 1, and yet another abuts against the side wall 211 of the pole body 21. Both the plastic component 4 and the sealing ring 22 are made of fluororubber and are integrally molded. The explosion-proof valve 31 is made of EPDM material. In this example, the integral molding of the plastic component 4 and the sealing ring 22 reduces seams and potential leakage points during assembly, improving the overall sealing effect and structural strength. The use of EPDM material reduces costs while ensuring explosion-proof performance.

[0062] In some embodiments, such as Figures 9 to 11 As shown, the plastic component 4 surrounds the pole assembly 2. The plastic component 4 includes multiple abutting parts, one of which abuts against the bottom of the sealing ring 22, one of which abuts against the bottom of the cover plate body 1, and one of which abuts against the side wall 211 of the pole body 21. Both the plastic component 4 and the sealing ring 22 are made of fluororubber. The plastic component 4 and the sealing ring 22 are separately molded. Alternatively, the plastic component 4 is made of silicone rubber, the sealing ring 22 is made of fluororubber, and the explosion-proof valve 31 is made of EPDM. Or, both the plastic component 4 and the sealing ring 22 are made of fluororubber, and the explosion-proof valve 31 is made of EPDM.

[0063] In some embodiments, such as Figures 12 to 14 As shown, the plastic component 4 is integrally formed around the electrode assembly 2 (positive electrode assembly and negative electrode assembly) and the explosion-proof valve 31. The plastic component 4, the sealing ring 22, and the explosion-proof valve 31 are all made of EPDM material and are integrally molded. Integrating the plastic component 4, the sealing ring 22, and the explosion-proof valve 31 into one piece reduces processing steps and improves processing efficiency. Furthermore, it reduces seams and potential leakage points during assembly, improving the overall sealing effect and structural strength. The use of EPDM material for the plastic component 4, the sealing ring 22, and the explosion-proof valve 31 provides excellent resistance to various chemicals and high temperatures, protecting against the effects of electrolytes and other corrosive substances, extending the component's service life, and reducing costs.

[0064] In some embodiments, such as Figures 15 to 17As shown, the plastic part 4 is provided with a first connecting piece and a second connecting piece, the sealing ring 22 is formed with a third connecting piece 5, the explosion-proof valve 31 is provided with a fourth connecting piece 6, and the first connecting piece and the third connecting piece 5 are matched with each other, and the second connecting piece and the fourth connecting piece 6 are matched with each other, so that the plastic part 4 is integrally arranged 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 piece 5 and the sealing ring 22 are made of fluororubber material, and the third connecting piece 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 piece 6 and the explosion-proof valve 31 are made of EPDM material, and the fourth connecting piece 6 and the explosion-proof valve 31 are integrally formed. The connecting pieces are used to connect the sealing ring 22 and the plastic part 4, and the explosion-proof valve 31 and the plastic part 4, thereby enhancing the stability of the overall structure, and the split structure can optimize the dispersion and management of heat, reduce the temperature of the battery assembly during work, and improve the safety and service life of the battery.

[0065] In some embodiments, the plastic part 4 is provided with a first connecting piece and a second connecting piece, the sealing ring 22 is formed with a third connecting piece 5, the explosion-proof valve 31 is provided with a fourth connecting piece 6, and the first connecting piece and the third connecting piece 5 are matched with each other, and the second connecting piece and the fourth connecting piece 6 are matched with each other, so that the plastic part 4 is integrally arranged 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, the sealing ring 22 is arranged around the pole assembly 2 and integrally formed with the explosion-proof valve 31 (the integrally formed structure is not shown separately, and the remaining structural relationship is referred to Figures 15 to 17 ), and the sealing ring 22 and the explosion-proof valve 31 are made of EPDM material. The connecting pieces are used to connect the sealing ring 22 and the plastic part 4, and the explosion-proof valve 31 and the plastic part 4, thereby enhancing the stability of the overall structure, and the split structure can optimize the dispersion and management of heat, reduce the temperature of the battery assembly during work, 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, which comprises the battery cover plate assembly with improved air tightness according to any one of the above.

[0067] The basic principles, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the present application.

Claims

1. A battery cover plate assembly having improved air tightness, characterized by, The battery cover plate assembly comprises a cover plate body (1), a pole column assembly (2) assembled on the cover plate body (1), and a plastic part (4) supported at the bottom of the cover plate body (1), the cover plate body (1) is provided with a pole column hole (11), the pole column assembly (2) is assembled in cooperation with the pole column hole (11), the pole column assembly (2) comprises a pole column body (21) and a sealing ring (22), the pole column body (21) penetrates through the pole column hole (11), and a sealing gap with a compression allowance 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), the sealing gap is filled by compressing the sealing ring (22), and the cover plate body (1) on one side of the sealing gap is provided with a cover plate step (12); the sealing ring (22) comprises an inner wall (220) and an outer wall (221) spaced apart from the inner wall (220) by a target width, the inner wall (220) cooperates with a column side wall (211) of the pole column body (21), a gradient step matched with the cover plate step (12) and a transition connecting surface (224) are formed in the target width direction of the sealing ring (22), the gradient step comprises at least one step, each step comprises a step plane (222) and a step connecting surface (223), the step plane (222) and the transition connecting surface (224) or two adjacent step planes (222) are connected by a step connecting surface (223), and the inner wall (220) is a slope and / or at least one step connecting surface (223) in at least one step is a slope.

2. The hermeticity-improvable battery cover plate assembly according to claim 1, wherein The battery cover plate assembly further comprises an explosion-proof valve (31) matched with an explosion-proof hole (14) formed on the cover plate body (1), and the sealing ring (22) and the explosion-proof valve (31) are both made of rubber.

3. The hermeticity-improvable battery cover plate assembly according to claim 2, wherein The material of the explosion-proof valve (31) is EDPM or TPV or fluororubber.

4. The hermeticity-improvable battery cover plate assembly according to claim 3, wherein The explosion-proof valve (31) comprises an outer ring wall, an annular table (227) protrudes outward on the outer ring wall, an annular groove (13) is formed on the cover plate body (1), the annular table (227) is arranged in the annular groove (13), the explosion-proof assembly further comprises a pressing plate (3), the annular table (227) is embedded in the annular groove (13), the pressing plate (3) presses the other side of the annular table (227), and the pressing plate (3) is welded with the cover plate body (1).

5. The hermeticity-improvable battery cover plate assembly according to claim 4, wherein An electric core cover plate is arranged above the pole column assembly (2), a top surface of the explosion-proof valve (31) is coated with a conductive material, when the explosion-proof valve (31) is protruded to a first target height under the action of air pressure, the conductive material is in contact with a circuit contact on the electric core cover plate, working data of the electric core is read, so that the battery management system determines an abnormal electric core through the working data, wherein the working data at least comprises an electric core temperature.

6. The hermeticity-improvable battery lid plate assembly according to claim 4 or 5, characterized by, The anti-explosion valve (31) is further provided with a piercing needle above the anti-explosion valve (31), the piercing needle is above the cover plate of the battery cell, and the anti-explosion valve (31) is pierced by the piercing needle to release pressure when the anti-explosion valve (31) is bulged to a second target height, the second target height is higher than the first target height.

7. The hermeticity-improvable battery lid plate assembly according to claim 4 or 5, characterized by, The size of the anti-explosion valve (31) is determined based on the pressure storage requirement.

8. The hermeticity-improvable battery cover plate assembly according to claim 2, wherein The plastic part (4) is arranged around the pole assembly (2), the plastic part (4) includes multiple abutting parts, one of the multiple abutting parts is arranged below the sealing ring (22), one of the multiple abutting parts is arranged at the bottom of the cover plate body (1), and one of the multiple abutting parts is arranged in abutment with the pole body (21).

9. The hermeticity-improvable battery cover plate assembly according to claim 8, wherein 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, and the anti-explosion valve (31) is made of EPDM.

10. The hermeticity-improvable battery cover plate assembly according to claim 8, wherein The plastic part (4) and the sealing ring (22) are made of fluororubber, and the anti-explosion valve is made of EPDM.

11. The hermeticity-improvable battery cover plate assembly according to claim 2, wherein The plastic part (4) is integrally arranged around the pole assembly (2) and the anti-explosion valve (31), the plastic part (4), the sealing ring (22), and the anti-explosion valve (31) are made of EPDM, and the plastic part (4), the sealing ring (22), and the anti-explosion valve (31) are integrally formed.

12. The hermeticity-improvable battery cover plate assembly according to claim 2, wherein The plastic part (4) is provided with a first connecting part and a second connecting part, the sealing ring (22) is provided with a third connecting part (5), the anti-explosion valve (31) is provided with a fourth connecting part (6), and the first connecting part and the third connecting part are matched with each other, and the second connecting part and the fourth connecting part (6) are matched with each other, so that the plastic part (4) is integrally arranged around the pole assembly (2) and the anti-explosion valve (31).

13. The hermeticity-improvable battery cover plate assembly according to claim 12, wherein The plastic part (4) is made of EPDM or TPV, the third connecting part (5) and the sealing ring (22) are made of fluororubber, the third connecting part (5) and the sealing ring (22) are integrally formed, the fourth connecting part (6) and the anti-explosion valve (31) are made of EPDM, and the fourth connecting part (6) and the anti-explosion valve (31) are integrally formed.

14. The hermeticity-improvable battery cover plate assembly according to claim 12, wherein The sealing ring (22) is integrally formed by injection molding, the sealing ring (22) is integrally arranged around the pole assembly (2) and the anti-explosion valve (31), and the sealing ring (22) and the anti-explosion valve (31) are made of EPDM.

15. A power cell, characterized by The power battery includes the battery cover plate assembly with improved air tightness according to any one of claims 1 to 14.

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