Battery cover plate and battery

Abstract

The invention relates to the technical field of batteries, and discloses a battery cover plate and a battery. A first through hole is formed in a cover plate main body; the injection molding insulating part comprises a first plastic part and a second plastic part, part of the first plastic part is embedded into the first through hole, the second plastic part is arranged on the side, away from the first plastic part, of the cover plate body, the first plastic part and the second plastic part are integrally arranged in an injection molding mode, and a second through hole is formed in the injection molding insulating part and penetrates through the first plastic part and the second plastic part. The first plastic part and the second plastic part are integrally formed through injection molding, so that the assembly procedure of injection molding of the insulating part is reduced, and the assembly efficiency is further improved; through the arrangement of the first through hole and the second through hole, the tab of the battery can directly penetrate out of the second through hole and is bent above the battery cover plate so as to directly connect and transmit electric quantity outwards, so that the space occupied by the battery cover plate in the battery shell is reduced, and the space utilization rate in the battery shell can be further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a battery cover and a battery. Background Art

[0002] With the large-scale application of renewable energy, the energy storage market will develop rapidly. As one of the important energy storage devices, batteries play an important role in the energy storage market. In order to meet the requirements of battery performance in application scenarios such as mobile devices and electric vehicles, the energy density of batteries is constantly increasing.

[0003] In the prior art, the battery tabs transfer electricity to the outside through connecting plates, and the connecting plates are arranged inside the battery shell, thus occupying the internal space of the battery shell, resulting in a low energy density of the battery, and the upper and lower plastics of the battery are respectively connected to the cover body, and the assembly process has many steps. Summary of the invention

[0004] In view of this, the present invention provides a battery cover and a battery to solve the problem that the battery has low energy density and the battery cover has many assembly steps.

[0005] In a first aspect, the present invention provides a battery cover, comprising: a cover body, the cover body being provided with a first through hole; an injection-molded insulating part, the injection-molded insulating part comprising a first plastic part and a second plastic part, along the thickness direction of the battery cover, part of the first plastic part is embedded in the first through hole, the second plastic part is arranged on a side of the cover body away from the first plastic part, the first plastic part and the second plastic part are integrally injection-molded, a second through hole is provided on the injection-molded insulating part, and the second through hole passes through the first plastic part and the second plastic part.

[0006] Beneficial effects: The first plastic part and the second plastic part are integrally injection molded, which reduces the assembly process of the injection-molded insulating parts and improves the assembly efficiency; by setting the first perforation and the second perforation, the battery ear can directly pass through the second perforation and bend above the battery cover to directly connect to the outside to transfer electricity, reducing the space occupied by the battery cover inside the battery shell, thereby further improving the space utilization inside the battery shell.

[0007] In an optional embodiment, the second through hole is suitable for the pole lug to pass through, and along the length direction of the battery cover plate, the width of the pole lug is A, and the length of the second through hole is B, satisfying 0.5≤A / B≤0.95.

[0008] Beneficial effect: By limiting the ratio between the width dimension of the pole ear and the length dimension of the second perforation, while ensuring the structural strength of the battery cover, the pole ear is prevented from colliding with the hole wall of the second perforation, thereby avoiding damage to the pole ear.

[0009] In an optional embodiment, a plurality of the second through holes are provided, and along the thickness direction of the battery cover plate, the plurality of the second through holes are spaced apart on the injection-molded insulating member.

[0010] In an optional embodiment, a mounting groove is formed on a side of the cover plate body close to the first plastic part, and the first plastic part is embedded in the mounting groove.

[0011] Beneficial effect: By providing the installation groove, the first plastic part is embedded in the installation groove for installation, thereby reducing the overall thickness of the battery cover and reducing the space occupied by the battery.

[0012] In an optional embodiment, the first plastic part includes a main body and a flange part, the flange part is arranged along the circumference of the main body and connected to the main body, the main body is embedded in the first through-hole arrangement, the main body is connected to the second plastic part, the flange part, the main body and the second plastic part enclose a clamping space, and the cover body is arranged in the clamping space.

[0013] Beneficial effect: By providing the flange portion, the position limitation between the first plastic part and the cover plate body is further achieved, and the sealing of the battery cover plate is improved.

[0014] In an optional embodiment, along the thickness direction of the battery cover, the distance from the side of the flange away from the second plastic part to the side of the cover body away from the second plastic part is C, and the thickness of the battery cover is E, satisfying 0≤C≤0.5Emm.

[0015] Beneficial effect: By limiting the distance from the side of the flange away from the second plastic part to the side of the cover plate body away from the second plastic part, the structural strength of the cover plate is ensured while improving the battery space utilization.

[0016] In an optional implementation, along the width direction of the battery cover, the width of the flange portion is D, satisfying 1 mm ≤ D ≤ 10 mm.

[0017] Beneficial effect: By limiting the width of the flange, it is possible to ensure that the flange can be fixed on the cover body while avoiding excessive weight of the flange, increasing costs and affecting the cover design.

[0018] In an optional embodiment, a liquid injection hole is opened on the cover plate body, and the liquid injection hole is set through the cover plate body.

[0019] Beneficial effect: When the electrolyte of the battery needs to be supplemented, the electrolyte is directly added into the battery through the injection hole without opening the battery cover, which is convenient for operation.

[0020] In an optional embodiment, the battery cover plate also includes an explosion-proof valve, a first air vent is opened on the cover plate body, a second air vent is opened on the injection-molded insulating part, the first air vent and the second air vent are connected to each other, and the explosion-proof valve is connected to the cover plate body and is arranged corresponding to the first air vent.

[0021] Beneficial effect: During the use of the battery, gas is easily generated inside the battery. When the pressure inside the battery is too high, the gas inside the battery is discharged to the outside through the explosion-proof valve to prevent the excessive internal pressure of the battery from affecting the battery performance.

[0022] In a second aspect, the present invention further provides a battery, comprising the above-mentioned battery cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a schematic diagram of the structure explosion of the battery cover plate of an embodiment of the present invention (front view);

[0025] Figure 2 It is a schematic diagram of the structure explosion of the battery cover plate of an embodiment of the present invention (reverse);

[0026] Figure 3 A schematic diagram of the top structure of a battery cover plate according to an embodiment of the present invention;

[0027] Figure 4 for Figure 3 GG section view in;

[0028] Figure 5 It is a schematic diagram of the explosion structure of the battery cover plate of an embodiment of the present invention before the sealing ring and the pole are assembled in the second stage of the pressure test;

[0029] Figure 6 It is a cross-sectional view of the assembly structure of the battery cover plate of an embodiment of the present invention after the sealing ring and the pole are assembled in the second stage of the pressure test.

[0030] Description of reference numerals:

[0031] 10. Cover plate body; 11. First through hole; 12. Mounting groove; 13. Liquid injection hole; 14. First vent hole; 20. Injection-molded insulating part; 21. First plastic part; 211. Main body; 212. Flange; 22. Second plastic part; 23. Second through hole; 24. Second vent hole; 30. Explosion-proof valve; 40. Sealing ring; 50. Pole. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0033] Combine the following Figures 1 to 4 , describing an embodiment of the present invention.

[0034] According to an embodiment of the present invention, in a first aspect, a battery cover is provided, comprising a cover body 10 and an injection-molded insulating member 20. The cover body 10 is provided with a first through hole 11; the injection-molded insulating member 20 comprises a first plastic member 21 and a second plastic member 22. Along the thickness direction of the battery cover, part of the first plastic member 21 is embedded in the first through hole 11, and the second plastic member 22 is arranged on a side of the cover body 10 away from the first plastic member 21. The first plastic member 21 and the second plastic member 22 are integrally injection-molded. A second through hole 23 is provided on the injection-molded insulating member 20, and the second through hole 23 passes through the first plastic member 21 and the second plastic member 22.

[0035] The battery cover plate of the present embodiment is integrally injection molded by the first plastic part 21 and the second plastic part 22, thereby reducing the assembly process of the injection-molded insulating part 20 and improving the assembly efficiency; by providing the first perforation 11 and the second perforation 23, the battery pole ear can be directly passed through the cover plate body 10 and bent above the battery cover plate to directly connect to the outside to transfer electricity, thereby reducing the space occupied by the battery cover plate inside the battery shell, thereby further improving the space utilization inside the battery shell.

[0036] Specifically, in this embodiment, the first plastic part 21 is an upper plastic, the second plastic part 22 is a lower plastic, and a portion of the upper plastic is embedded in the first through hole 11 and is integrally formed with the lower plastic.

[0037] For details, please refer to Figure 1 In this embodiment, the battery cover is provided with two poles, two first plastic parts 21 are provided at intervals, and the second plastic part 22 is a flat plastic part.

[0038] Of course, in other alternative implementations, the battery cover may be provided with only one pole, and the first plastic part 21 may be provided with only one pole.

[0039] It should be noted that in the related art, the pole ear on the pole group realizes the power transmission between the pole group and the outside through the connecting sheet, and the connecting sheet occupies the space inside the battery shell. In this embodiment, the pole ear directly passes through the second perforation 23 and is bent above the battery cover plate. The pole ear directly transmits power to the outside, reducing the use of the connecting sheet, thereby reducing the occupied space inside the battery shell. The space inside the battery shell can be fully utilized by methods such as expanding the size of the pole group, thereby improving the space utilization rate inside the battery shell.

[0040] It should be noted that in the related art, the first plastic part 21 and the second plastic part 22 are separately provided, and the first plastic part 21 and the second plastic part 22 need to be assembled and assembled to the two sides of the cover body 10. In this embodiment, the first plastic part 21 and the second plastic part 22 are integrally injection molded, which reduces the assembly process of the injection-molded insulating part 20, thereby improving the assembly efficiency.

[0041] In one embodiment, Figure 3 As shown, the second through hole 23 is suitable for the tab to pass through. Along the length direction of the battery cover, the width of the tab is A, and the length of the second through hole 23 is B, which satisfies 0.5≤A / B≤0.95. By limiting the ratio between the width of the tab and the length of the second through hole 23, while ensuring the structural strength of the battery cover, the tab is prevented from colliding with the hole wall of the second through hole 23, thereby avoiding damage to the tab.

[0042] It should be noted that when A / B>0.95, it is difficult for the pole ear to pass through the second perforation 23, and the two sides of the pole ear are easy to hit the hole wall of the second perforation 23, which can easily cause damage to the pole ear, and too small a gap is not conducive to the rapid penetration of the pole ear, affecting the progress of the process; when A / B<0.5, the opening length of the second perforation 23 is too long. Although it is convenient for the pole ear to pass through, the excessive length of the second perforation 23 causes the length of the first perforation 11 to be too long. The excessive length of the first perforation 11 reduces the structural strength of the cover body 10, thereby affecting the structural strength of the battery cover.

[0043] In one embodiment, Figure 1 and Figure 2 As shown, a plurality of second through holes 23 are provided, and along the thickness direction of the battery cover, a plurality of second through holes 23 are spaced apart and arranged on the injection-molded insulating member 20 .

[0044] Specifically, in this embodiment, four second through holes 23 are provided, two first plastic parts 21 are provided, and each first plastic part 21 is provided with two second through holes 23 that are spaced apart.

[0045] Of course, in other alternative embodiments, the number of the second through holes 23 can be adjusted according to actual needs.

[0046] In one embodiment, Figure 1 and Figure 3 As shown, a mounting groove 12 is provided on one side of the cover body 10 close to the first plastic part 21, and the first plastic part 21 is embedded in the mounting groove 12. By providing the mounting groove 12 and embedding the first plastic part 21 in the mounting groove 12, the overall thickness of the battery cover is reduced, and the space occupied by the battery is reduced.

[0047] It should be noted that in the related art, the mounting groove 12 is not provided. After the injection-molded insulating member 20 is installed with the cover body 10, the overall thickness of the battery cover is the sum of the thicknesses of the first plastic member 21, the second plastic member 22 and the cover body 10. In this embodiment, the cover body 10 is provided with the mounting groove 12. After the first plastic member 21 is embedded in the mounting groove 12 and installed, in the thickness direction of the battery cover, the thickness of part of the first plastic member 21 overlaps with the thickness of part of the cover body 10. Therefore, the overall thickness of the battery cover is reduced, and the space occupied by the battery is reduced.

[0048] In one embodiment, Figure 3 and Figure 4 As shown in FIG. 1 , the first plastic part 21 includes a main body 211 and a flange 212. The flange 212 is arranged along the circumference of the main body 211 and connected to the main body 211. The main body 211 is embedded in the first through hole 11. The main body 211 is connected to the second plastic part 22. The flange 212, the main body 211 and the second plastic part 22 enclose a clamping space, and the cover body 10 is arranged in the clamping space. By setting the flange 212, the first plastic part and the cover body 10 are further limited, and the sealing of the battery cover is improved.

[0049] It should be noted that if only the main body 211 is provided, liquid may leak downward from between the main body 211 and the first through hole 11 , thereby affecting the sealing performance of the battery cover.

[0050] It can be understood that, by providing the flange portion 212 , the flange portion 212 blocks the risk of liquid directly leaking downward from between the main body portion 211 and the first through hole 11 , thereby improving the sealing performance of the battery cover.

[0051] In one embodiment, Figure 4As shown, along the thickness direction of the battery cover, the distance from the side of the flange 212 away from the second plastic part 22 to the side of the cover body 10 away from the second plastic part 22 is C, and the thickness of the battery cover is E, which satisfies 0≤C≤0.5Emm. By limiting the distance from the side of the flange 212 away from the second plastic part 22 to the side of the cover body 10 away from the second plastic part 22, the structural strength of the battery cover is ensured while improving the utilization rate of the battery cell space.

[0052] It should be noted that, along the thickness direction of the battery cover, the side of the flange portion 212 away from the second plastic part 22 is lower than the side of the cover body 10 away from the second plastic part 22. When C>0.5Emm, the depth of the mounting groove 12 is too deep, which in turn affects the structural strength of the cover body 10, thereby reducing the overall strength of the battery cover. During the use of the battery, the cover body 10 may crack, affecting the battery performance and battery safety. Therefore, while the mounting groove 12 is provided on the cover body 10 to reduce the overall height of the battery cover, it is necessary to limit the distance from the upper surface of the first plastic part 21 to the side of the cover body 10 away from the second plastic part 22 to ensure the structural strength of the battery cover.

[0053] In one embodiment, Figure 4 As shown, along the width direction of the battery cover, the width of the flange portion 212 is D, which satisfies 1mm≤D≤10mm. By limiting the width dimension of the flange portion 212, while ensuring that the flange portion 212 can be fixed on the cover body 10, it is avoided that the weight of the flange portion 212 is too large, which increases the cost and affects the cover design.

[0054] It should be noted that when D is less than 1 mm, the width of the flange portion 212 is too small, the limiting effect is small, and it is difficult to fix on the cover body 10; when D is greater than 10 mm, although the flange portion 212 can play a limiting effect, the width of the flange portion 212 is too large, which increases the overall weight of the battery cover and increases the cost.

[0055] In one embodiment, Figure 1 As shown, a liquid injection hole 13 is opened on the cover plate body 10 , and the liquid injection hole 13 is set through the cover plate body 10 .

[0056] It should be noted that after the injection is completed, the injection hole 13 needs to be sealed with a sealing nail or a sealing ball to prevent leakage of the electrolyte. At the same time, before and after sealing, it is also necessary to perform operations such as infiltration and pressure testing through the injection hole 13 to ensure the sealing and safety of the battery.

[0057] In one embodiment, Figure 1As shown, the battery cover also includes an explosion-proof valve 30, a first vent hole 14 is provided on the cover body 10, a second vent hole 24 is provided on the injection-molded insulating member 20, the first vent hole 14 and the second vent hole 24 are connected and arranged correspondingly, and the explosion-proof valve 30 is connected to the cover body 10 and arranged correspondingly to the first vent hole 14. During the use of the battery, gas is easily generated inside the battery. When the pressure inside the battery is too high, the gas inside the battery is discharged outwardly through the explosion-proof valve 30 to prevent the excessive pressure inside the battery from affecting the battery performance.

[0058] It should be noted that when the temperature inside the battery is too high or the pressure is too high, a chemical reaction will occur inside the battery, generating a large amount of gas, causing the internal pressure of the battery to continue to increase. If the pressure is not released in time, the battery may explode due to excessive internal pressure. The explosion-proof valve 30 can automatically open in this case to dissipate the high-pressure gas directly to the outside, thereby avoiding battery explosion and improving the safety of the battery.

[0059] Next, CT (Computer Tomography) detection, short circuit detection and disassembly detection are performed on battery cover plates with different A / B ratios (the ratio between the width dimension of the pole ear and the length dimension of the second perforation 23). The specific test results are shown in Table 1 below.

[0060] Specifically, the specific operation of the CT detection is: after the tab passes through the second through hole 23, the tab is subjected to CT detection.

[0061] Specifically, the specific operation of the short-circuit detection is: after the tabs are installed, a test current is connected between the positive and negative tabs to detect whether a short circuit occurs. If a short circuit occurs, the short-circuit detection fails.

[0062] Specifically, the disassembly and inspection operations are as follows: removing the tabs from the battery cover and performing a visual inspection of the tabs.

[0063] Table 1 CT test, short circuit test and disassembly test results

[0064]

[0065] It can be concluded from the test results in Table 1 that in Examples 1 to 13, 0.5≤A / B≤0.95 is satisfied, and after the tab passes through the second perforation 23, the CT detection of the tab shows no abnormality; the test current is connected between the positive and negative tabs, and no short circuit occurs; after the tab is disassembled from the battery cover, the tab is visually inspected to show no abnormality.

[0066] It can be seen from the test results in Table 1 that in Comparative Example 1, A / B is less than 0.5. In this case, although there are no abnormalities in CT detection, short circuit detection and disassembly detection, the structural strength of the battery cover is greatly weakened due to the large length of the second perforation and the short width of the tab. Therefore, it is not recommended for use.

[0067] It can be seen from the test results in Table 1 that in Comparative Example 2, after the tab was disassembled from the battery cover, it was found that the base of the tab was torn, and therefore did not meet the requirements.

[0068] Next, pressure tests were performed on battery covers with different dimensions C (the distance from the side of the flange 212 away from the second plastic part 22 to the side of the cover body 10 away from the second plastic part 22) and different dimensions D (the width of the flange 212). The specific results are shown in Table 2 below.

[0069] Specifically, the pressure test includes two stages. The first stage is to directly apply a pressure of 800N to the fixed injection-molded insulating part 20, and observe the injection-molded insulating part 20 and the cover body 10 after the pressure is applied; the second stage is to set a sealing ring 40 on the outside of the first plastic part 21, and then cover the pole 50 on the upper side of the first plastic part 21 and the sealing ring 40; then, pressure is applied to the upper side of the pole 50 to compress the sealing ring 40, and then the cover body 10 is observed.

[0070] Specifically, during the second stage of pressure testing, the relative positions of the sealing ring 40 and the pole 50 are shown in FIG. Figure 5 and Figure 6 .

[0071] Table 2 Stress test results

[0072]

[0073] It can be seen from the test results in Table 2 that in Examples 1 to 8, 0≤C≤0.5E and 1mm≤D≤10mm are satisfied. After the first and second stage pressure tests, no obvious deformation is found in the injection-molded insulating part 20, no obvious deformation is found in the cover plate body 10, and no obvious deformation is found in the cover plate body 10 after the sealing ring 40 is compressed.

[0074] It can be seen from the test results in Table 2 that in comparative example 1, C<0, the main body 211 of the first plastic part 21 protrudes from the upper surface of the cover body 10, thereby increasing the height of the pole, affecting the improvement of the battery volume energy density, and is not recommended for use.

[0075] It should be noted that when the value of C is negative, the main body 211 of the first plastic part 21 protrudes from the upper surface of the cover body 10 , and when the value of C is positive, the main body 211 of the first plastic part 21 is lower than the upper surface of the cover body 10 .

[0076] It can be seen from the test results in Table 2 that in comparative example 4, C>0.5E, after the first stage of pressure testing, the cover body 10 is slightly deformed; after the second stage of pressure testing, the cover body 10 is slightly deformed after the sealing ring 40 is compressed, so it is not recommended for use.

[0077] It can be seen from the test results in Table 2 that in Comparative Example 2, D is less than 1 mm, the width of the flange portion 212 is small, the strength is weak, and the injection molded insulating part 20 is deformed; the width of the flange portion 212 is small, and the injection molded insulating part 20 is easy to deform downward, which will cause the battery insulation to fail, so it is not recommended for use.

[0078] It can be seen from the test results in Table 2 that in Comparative Example 3, D>10mm. Although no obvious deformation was found in the injection-molded insulating part 20 and the cover body 10 after the first and second stage pressure tests, the width of the flange portion 212 is relatively wide, which affects the size of the sealing ring 40 and the size design of the cover body 10, resulting in increased costs. Therefore, it is not recommended for use.

[0079] According to an embodiment of the present invention, in a second aspect, a battery is further provided, comprising the above-mentioned battery cover.

[0080] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the present invention.

Claims

1. A battery cover, characterized in that: include: A cover plate body, wherein the cover plate body is provided with a first through hole; An injection-molded insulating part, the injection-molded insulating part includes a first plastic part and a second plastic part. Along the thickness direction of the battery cover, part of the first plastic part is embedded in the first perforation, the second plastic part is arranged on the side of the cover body away from the first plastic part, the first plastic part and the second plastic part are integrally injection-molded, and a second perforation is opened on the injection-molded insulating part, and the second perforation passes through the first plastic part and the second plastic part.

2. The battery cover according to claim 1, characterized in that: The second through hole is suitable for the pole lug to pass through. Along the length direction of the battery cover plate, the width of the pole lug is A, and the length of the second through hole is B, satisfying 0.5≤A / B≤0.

95.

3. The battery cover according to claim 2, characterized in that: A plurality of the second through holes are provided, and along the thickness direction of the battery cover plate, the plurality of the second through holes are arranged at intervals on the injection-molded insulating member.

4. The battery cover according to any one of claims 1 to 3, characterized in that: A mounting groove is provided on one side of the cover plate body close to the first plastic part, and the first plastic part is embedded in the mounting groove.

5. The battery cover according to any one of claims 4, characterized in that: The first plastic part includes a main body and a flange part, the flange part is arranged along the circumference of the main body and connected to the main body, the main body is embedded in the first through-hole, the main body is connected to the second plastic part, the flange part, the main body and the second plastic part enclose a clamping space, and the cover body is arranged in the clamping space.

6. The battery cover according to claim 5, characterized in that: Along the thickness direction of the battery cover, the distance from the side of the flange away from the second plastic part to the side of the cover body away from the second plastic part is C, and the thickness of the battery cover is E, satisfying 0≤C≤0.5Emm.

7. The battery cover according to claim 5, characterized in that: Along the width direction of the battery cover, the width of the flange portion is D, satisfying 1mm≤D≤10mm.

8. The battery cover according to any one of claims 1 to 3, characterized in that: The cover plate body is provided with a liquid injection hole, and the liquid injection hole is arranged through the cover plate body.

9. The battery cover according to any one of claims 1 to 3, characterized in that: The battery cover also includes an explosion-proof valve. A first vent is provided on the cover body, a second vent is provided on the injection-molded insulating member, the first vent and the second vent are connected to each other, and the explosion-proof valve is connected to the cover body and is provided corresponding to the first vent.

10. A battery, characterized in that: A battery cover comprising the battery cover according to any one of claims 1 to 9.

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