Battery cover plate assembly, battery and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery cover plate assembly, a battery and a battery pack, the battery cover plate assembly comprises a cover plate body, a lower insulating part and at least one stopping part, and an explosion-proof mechanism is arranged on the cover plate body; the lower insulating part is connected with the cover plate body and is provided with at least one mounting groove with an opening facing the cover plate body; the stop piece is arranged in the mounting groove in an interference manner, and the orthographic projection of the stop piece on the cover plate body is not completely overlapped with the explosion-proof mechanism; and the stop piece is made of a high-temperature-resistant material. According to the battery cover plate assembly disclosed by the utility model, when the battery cell triggers thermal runaway and the lower insulating part is melted, the stop piece can be supported between the cover plate body and the pole group, so that the pole group is effectively prevented from moving towards the side of the anti-explosion mechanism and the anti-explosion mechanism is shielded, and the stop piece is supported between the cover plate body and the pole group, so that an exhaust channel is kept between the cover plate body and the pole group; the explosion-proof mechanism can normally exhaust and relieve pressure, the exhaust and heat dissipation effects of the explosion-proof valve are effectively improved, and the safety performance of the battery is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a battery cover assembly, a battery and a battery pack. Background Art

[0002] At present, the battery cell includes a shell, an electrode group and a cover plate assembly. The shell has an inner cavity for accommodating the electrode group. One end of the shell is open. The cover plate is arranged at the open end of the shell to encapsulate the electrode group in the shell.

[0003] The cover assembly includes an explosion-proof valve and an insulating protection structure, which can well protect the electrode group during the battery cell manufacturing process and normal use, and avoid abnormal connection and short circuit inside the battery cell.

[0004] The current battery cells use plastic materials such as PP for their insulating protection structures. When the battery cell experiences thermal runaway, the internal temperature can reach over 600°C in a short period of time. The plastic materials of the insulating protection structure will quickly melt and fail. At this time, only the electrode group is left inside the shell. Under the action of the internal high-temperature and high-pressure gas, the electrode group loses balance. Since the pressure at the cover explosion-proof valve is relatively low, the electrode group can easily move toward the explosion-proof valve, thereby blocking the explosion-proof valve and causing the battery to fail to release pressure in time, resulting in fire and explosion. Utility Model Content

[0005] In view of this, the utility model provides a battery cover assembly, a battery and a battery pack to solve the problem that the explosion-proof valve is easily blocked by the pole group when thermal runaway occurs in the battery cell.

[0006] In the first aspect, the utility model provides a battery cover assembly, including a cover body, a lower insulating member and at least one stop member, wherein the cover body is provided with an explosion-proof mechanism; the lower insulating member is connected to the cover body, and the lower insulating member is provided with at least one mounting groove, and the mounting groove opening faces the cover body; the stop member is interference fit in the mounting groove, and the orthographic projection of the stop member on the cover body does not completely overlap with the explosion-proof mechanism; the stop member is made of high temperature resistant material.

[0007] Beneficial effects: By setting at least one stopper, the lower insulating member is provided with at least one mounting groove, and the stopper is installed in the mounting groove by interference fit, and the stopper is made of high temperature resistant material. When the battery cell triggers thermal runaway, after the lower insulating member melts, the stopper can be supported between the cover body and the pole group of the battery cell, effectively preventing the pole group from moving toward the explosion-proof mechanism, blocking the explosion-proof mechanism, and affecting the exhaust and heat dissipation of the battery, effectively improving the exhaust and heat dissipation effect of the explosion-proof valve, and greatly improving the safety performance of the battery. Since the positive projection of the stopper on the cover body does not completely overlap with the explosion-proof mechanism, after the lower insulating member melts, one side of the stopper at least partially abuts against the cover body, and the other side of the stopper abuts against the pole group of the battery cell, so that an exhaust channel is maintained between the cover body and the pole group, ensuring that the explosion-proof mechanism can be exhausted and decompressed normally.

[0008] In an optional embodiment, at least two side walls of the stopper are protrudingly provided with interference ribs, and the interference ribs and the inner wall of the mounting groove are interference fit, and the interference dimension is E, 0.2mm≤E≤0.7mm.

[0009] Beneficial effect: By protruding interference ribs on at least two side walls of the stopper, the stopper and the mounting groove of the lower insulating member are interference-fitted. The interference dimension E is controlled within the range of 0.2 mm to 0.7 mm, which can ensure that the stopper is fixedly assembled in the lower insulating member and is not prone to displacement or movement. At the same time, it can facilitate the assembly between the stopper and the mounting groove.

[0010] In an optional embodiment, the width of the interference rib is A, 0.5mm≤A≤1.5mm, and / or the length of the interference rib is B, 5mm≤B≤10mm, and / or the thickness of the interference rib protruding from the side wall of the stop member is C, 0.3mm≤C≤0.8mm.

[0011] Beneficial effect: This arrangement can ensure the interference fit between the stopper and the mounting groove while reducing the weight of the battery cover assembly.

[0012] In an optional embodiment, the angle between the length extension direction of the interference rib and the thickness direction of the cover plate body is in the range of 0° to 30°.

[0013] Beneficial effect: The angle α between the length extension direction of the interference rib and the thickness direction of the cover plate body is controlled within the range of 0° to 30°, which is convenient for assembly.

[0014] In an optional embodiment, the explosion-proof mechanism includes an explosion-proof valve, and the stopper is arranged between the explosion-proof valve and the lower insulating member. Along the width direction of the cover body, the width of the explosion-proof valve is W. 1 , the width of the stopper is W 2 , W 2 ≥W 1 .

[0015] Beneficial effect: This arrangement can prevent the lower insulating part from melting when thermal runaway occurs in the battery cell. Under the pushing action of the pole group of the battery cell, the stopper is still supported between the cover body and the pole group of the battery cell and will not fly out of the explosion-proof valve, ensuring that the stopper maintains the exhaust channel between the cover body and the pole group of the battery cell, thereby ensuring normal exhaust and pressure relief of the explosion-proof valve.

[0016] In an optional embodiment, a side wall of the stopper is provided with a plurality of interference ribs, and a distance between adjacent interference ribs is D, 5mm≤D≤10mm.

[0017] Beneficial effect: This arrangement can ensure an interference fit between the stopper and the mounting groove, thereby ensuring a stable connection between the stopper and the lower insulating member, while also ensuring a reasonable number of interference ribs and reducing the weight of the battery cover assembly.

[0018] In an optional embodiment, the stopper is a block structure, and the cross-section of the stopper includes a rectangle or a T-shape; or, the stopper is a frame structure, and the stopper is provided with a first liquid passage hole penetrating two opposite side walls in at least one direction.

[0019] Beneficial effect: By setting the first liquid hole on the stopper, the stopper can not only play a supporting role between the cover body and the electrode group of the battery cell, but also facilitate the passage of electrolyte and prevent the electrolyte from docking at the stopper, thereby ensuring the performance of the battery cell.

[0020] In an optional embodiment, a second liquid passage hole penetrating through the lower insulating member is provided on the bottom wall of the mounting groove of the lower insulating member.

[0021] Beneficial effect: By arranging a second liquid passage hole penetrating through the lower insulating member on the bottom wall of the mounting groove of the lower insulating member, it is possible to further facilitate the passage of electrolyte, prevent the electrolyte from accumulating in the mounting groove, and ensure the performance of the battery cell.

[0022] In the second aspect, the utility model also provides a battery, comprising a shell, a pole group and a battery cover assembly as described in any one of the above technical solutions, the shell having a receiving cavity with at least one end open; the pole group is arranged in the receiving cavity of the shell; the battery cover assembly is arranged at the open end of the shell, and is used to encapsulate the pole group in the shell.

[0023] Beneficial effects: Because the battery includes a battery cover assembly, when the battery cell triggers thermal runaway, after the lower insulating member melts, the stopper can be supported between the cover body and the pole group of the battery cell, effectively preventing the pole group from moving toward the explosion-proof mechanism, shielding the explosion-proof mechanism, and affecting the exhaust and heat dissipation of the battery, effectively improving the exhaust and heat dissipation effect of the explosion-proof valve, and greatly improving the safety performance of the battery. Since the positive projection of the stopper on the cover body does not completely overlap with the explosion-proof mechanism, after the lower insulating member melts, one side of the stopper at least partially abuts against the cover body, and the other side of the stopper abuts against the pole group of the battery cell, so that an exhaust channel is maintained between the cover body and the pole group, ensuring that the explosion-proof mechanism can normally exhaust and release pressure.

[0024] In a third aspect, the utility model also provides a battery pack, comprising the battery described in the above technical solution.

[0025] Beneficial effect: Since the battery pack includes a battery cover assembly, it has the same effect as the battery and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific implementation methods of the utility model 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 utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 This is an axonometric view of a battery cover assembly according to an embodiment of the utility model;

[0028] Figure 2 for Figure 1 An exploded view of the structure of the battery cover assembly shown;

[0029] Figure 3 for Figure 1 A top view of

[0030] Figure 4 for Figure 3 Sectional view along AA;

[0031] Figure 5 for Figure 1 Axonometric view of the first stop member;

[0032] Figure 6 for Figure 5 A top view of

[0033] Figure 7 for Figure 6 A partial enlarged view of point B in the middle;

[0034] Figure 8 is a schematic structural diagram of a second stopper from a first perspective;

[0035] Fig. 9 for Figure 8 A schematic diagram of the structure of the stopper from a second viewing angle is shown;

[0036] Fig.10 is a schematic diagram of the structure of the third stopper;

[0037] Fig.11 Schematic diagram of the structure of the fourth stopper.

[0038] Description of reference numerals:

[0039] 10. Battery cover assembly; 1. Cover body; 2. Lower insulating member; 201. Mounting groove; 202. Second liquid hole; 3. Stop member; 301. Interference rib; 302. First liquid hole; 4. Explosion-proof mechanism; 5. Pole. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0041] Combine the following Figures 1 to 11 , describing an embodiment of the utility model.

[0042] According to the embodiments of the utility model, in the first aspect, the utility model provides a battery cover assembly 10, including a cover body 1, a lower insulating member 2 and at least one stop member 3, the cover body 1 is provided with an explosion-proof mechanism 4; the lower insulating member 2 is connected to the cover body 1, and the lower insulating member 2 is provided with at least one mounting groove 201, and the mounting groove 201 opens toward the cover body 1; the stop member 3 is interference fit in the mounting groove 201, and the orthographic projection of the stop member 3 on the cover body 1 does not completely overlap with the explosion-proof mechanism 4; the stop member 3 is made of high temperature resistant material.

[0043] The battery cover assembly 10 provided in this embodiment is provided with at least one stopper 3, and the lower insulating member 2 is provided with at least one mounting groove 201, and the stopper 3 is installed in the mounting groove 201 by interference fit, and the stopper 3 is made of high temperature resistant material. When the battery cell triggers thermal runaway, after the lower insulating member 2 melts, the stopper 3 can be supported between the cover body 1 and the pole group of the battery cell, effectively preventing the pole group from moving toward the explosion-proof mechanism 4, shielding the explosion-proof mechanism 4, affecting the exhaust heat dissipation of the battery, effectively improving the exhaust heat dissipation effect of the explosion-proof valve, and greatly improving the safety performance of the battery. Since the positive projection of the stopper 3 on the cover body 1 does not completely overlap with the explosion-proof mechanism 4, therefore, after the lower insulating member 2 melts, one side of the stopper 3 at least partially abuts against the cover body 1, and the other side of the stopper 3 abuts against the pole group of the battery cell, so that the exhaust channel is maintained between the cover body 1 and the pole group, ensuring that the explosion-proof mechanism 4 can be normally exhausted and depressurized.

[0044] Specifically, the stopper 3 is made of a material that is resistant to high temperatures and electrolytes. At the same time, the stopper 3 is also required to have a certain strength to resist the impact force of the pole group moving when the battery cell has thermal runaway, so as to ensure that the stopper 3 can be reliably supported between the pole group and the cover body 1, thereby ensuring that the explosion-proof valve is not blocked and that the explosion-proof valve can safely release pressure.

[0045] The number of the stopper 3 can be more than one, and correspondingly, the number of the mounting groove 201 of the lower insulating member 2 can also be more than one. It can be understood that the cover body 1 is provided with a pole 5, and the stopper can be set at any position between the cover body 1 and the lower insulating member 2, but it must avoid the pole 5 on the cover body 1.

[0046] Specifically, the lower insulating member 2 includes lower plastic.

[0047] In one embodiment, at least two side walls of the stopper 3 are protruded with interference ribs 301 , and the interference ribs 301 and the inner wall of the installation groove 201 are interference fit, and the interference dimension is E, 0.2mm≤E≤0.7mm.

[0048] By protruding interference ribs 301 on at least two side walls of the stopper 3, the stopper 3 and the mounting groove 201 of the lower insulating member 2 are interference-fitted. The interference dimension E is controlled within the range of 0.2 mm to 0.7 mm, which can ensure that the stopper 3 is fixedly assembled in the lower insulating member 2 and is not easily displaced or moved. At the same time, it can facilitate the assembly between the stopper 3 and the mounting groove 201.

[0049] In one embodiment, the stopper 3 is a block structure. Figure 5 and Figure 6 As shown, the stopper 3 is a rectangular parallelepiped structure. The interference ribs 301 are arranged in the following two ways: first, one interference rib 301 is arranged on each of the four sides of the stopper 3; second, interference ribs 301 are arranged on at least two sides of the stopper 3, and at least two interference ribs 301 are arranged on each side.

[0050] In one embodiment, the width of the interference rib 301 is A, 0.5mm≤A≤1.5mm, and / or the length of the interference rib 301 is B, 5mm≤B≤10mm, and / or the thickness of the interference rib 301 protruding from the side wall of the stopper 3 is C, 0.3mm≤C≤0.8mm.

[0051] like Figure 5 As shown, the width A of the interference rib 301 is controlled within the range of 0.5mm to 1.5mm, the length B of the interference rib 301 is controlled within the range of 5mm to 10mm, and the thickness C of the interference rib 301 protruding from the side wall of the stopper 3 is controlled within the range of 0.3mm to 0.8mm, which can ensure the interference fit between the stopper 3 and the mounting groove 201 while reducing the weight of the battery cover assembly 10.

[0052] In one embodiment, the angle between the length extension direction of the interference rib 301 and the thickness direction of the cover plate body 1 is in the range of 0° to 30°.

[0053] Specifically, the thickness direction of the cover body 1 is as follows: Figure 2 As shown in F, the angle α between the length extension direction of the interference rib 301 and the thickness direction of the cover plate body 1 is controlled within the range of 0° to 30° for easy assembly.

[0054] In one embodiment, the explosion-proof mechanism 4 includes an explosion-proof valve, and the stopper 3 is arranged between the explosion-proof valve and the lower insulating member 2. Along the width direction of the cover body 1, the width of the explosion-proof valve is W. 1 , the width of the stopper 3 is W 2 , W 2 ≥W 1 .

[0055] As shown in FIG2 , when the stopper 3 is disposed between the explosion-proof valve and the lower insulating member 2 , the width W of the stopper 3 along the width direction of the cover body 1 is 2 Not less than the width W of the explosion-proof valve 1 In this way, the lower insulating member 2 can be prevented from melting when thermal runaway occurs in the battery cell. Under the pushing action of the pole group of the battery cell, the stopper 3 is still supported between the cover body 1 and the pole group of the battery cell and will not fly out of the explosion-proof valve, ensuring that the stopper 3 maintains the exhaust channel between the cover body 1 and the pole group of the battery cell, thereby ensuring the normal exhaust and pressure relief of the explosion-proof valve.

[0056] In one embodiment, a side wall of the stopper 3 is provided with a plurality of interference ribs 301 , and the distance between adjacent interference ribs 301 is D, 5 mm ≤ D ≤ 10 mm.

[0057] When a plurality of interference ribs 301 are provided on a side wall of the stop member 3, the spacing D between adjacent interference ribs 301 is controlled within a range of 5 mm to 10 mm. This arrangement can ensure an interference fit between the stop member 3 and the mounting groove 201, thereby ensuring a firm connection between the stop member 3 and the lower insulating member 2, while at the same time ensuring a reasonable number of interference ribs 301 and reducing the weight of the battery cover assembly 10.

[0058] In one embodiment, the stopper 3 is a block structure, and the cross section of the stopper 3 includes a rectangle or a T-shape; or, the stopper 3 is a frame structure, and the stopper 3 is provided with a first liquid hole 302 penetrating two opposite side walls in at least one direction.

[0059] In one embodiment, if Figure 5 As shown, the cross section of the stopper 3 is a rectangle, that is, the stopper 3 is a rectangular block structure. At this time, the position and number of the interference ribs 301 can be determined according to the above two situations.

[0060] In another embodiment, Figure 8 or Fig. 9As shown, the cross section of the stopper 3 is T-shaped, which can reduce the weight of the stopper 3, thereby reducing the overall weight of the battery cover assembly 10. In this embodiment, the position and number of the interference ribs 301 can still be determined according to the above two situations.

[0061] In yet another embodiment, Fig.10 or Fig.11 As shown, the stopper 3 is a frame structure, which can also reduce the weight of the stopper 3, thereby reducing the overall weight of the battery cover assembly 10. In this embodiment, if multiple interference ribs 301 are set on the same side, the positions of the interference ribs 301 are not limited, for example, adjacent interference ribs 301 are staggered. Fig.10 and Fig.11 In the illustrated embodiment, first liquid-passing holes 302 penetrating two opposite side walls are provided in three directions of the stopper 3. By providing the first liquid-passing holes 302 on the stopper 3, the stopper 3 can not only play a supporting role between the cover body 1 and the electrode group of the battery cell, but also facilitate the passage of electrolyte, prevent the electrolyte from docking at the stopper 3, and thus ensure the performance of the battery cell.

[0062] Of course, the structure of the stopper 3 is not limited to the above-mentioned embodiment. For example, the cross section of the stopper 3 is a cross shape.

[0063] In one embodiment, the bottom wall of the mounting groove 201 of the lower insulating member 2 is provided with a second liquid passage hole 202 penetrating the lower insulating member 2 .

[0064] By providing a second liquid hole 202 penetrating through the lower insulating member 2 on the bottom wall of the mounting groove 201 of the lower insulating member 2, it is possible to further facilitate the passage of electrolyte, prevent the electrolyte from accumulating in the mounting groove 201, and ensure the performance of the battery cell.

[0065] In one embodiment, the lower insulating member 2 includes a body of the lower insulating member 2 and a boss protruding from the body of the lower insulating member 2 toward a direction away from the cover body 1, and the mounting groove 201 is provided on the boss. That is, the bottom of the mounting groove 201 and the lower end surface of the cover body 1 are not in the same plane. The bottom of the mounting groove 201 is further away from the cover body 1 than the body of the lower insulating member 2, and such a configuration can provide assembly space for the stopper 3.

[0066] In the second aspect, the utility model also provides a battery, comprising a shell, a pole group and a battery cover assembly 10 as described in any one of the above technical solutions, the shell having a receiving cavity with at least one end open; the pole group is arranged in the receiving cavity of the shell; the battery cover assembly 10 is arranged at the open end of the shell, and is used to encapsulate the pole group in the shell.

[0067] Since the battery includes the battery cover assembly 10 of the above-mentioned embodiment, when the battery cell triggers thermal runaway, after the lower insulating member 2 melts, the stopper 3 can be supported between the cover body 1 and the pole group of the battery cell, effectively preventing the pole group from moving toward the explosion-proof mechanism 4, shielding the explosion-proof mechanism 4, affecting the exhaust and heat dissipation of the battery, effectively improving the exhaust and heat dissipation effect of the explosion-proof valve, and greatly improving the safety performance of the battery. Since the positive projection of the stopper 3 on the cover body 1 does not completely overlap with the explosion-proof mechanism 4, after the lower insulating member 2 melts, one side of the stopper 3 at least partially abuts against the cover body 1, and the other side of the stopper 3 abuts against the pole group of the battery cell, so that the exhaust channel is maintained between the cover body 1 and the pole group, ensuring that the explosion-proof mechanism 4 can normally exhaust and release pressure.

[0068] In addition, because the battery includes the battery cover assembly 10, it also has other effects related to the battery cover assembly 10, which will not be described in detail here.

[0069] In a third aspect, the utility model also provides a battery pack, comprising the battery described in the above technical solution.

[0070] Since the battery pack includes the battery of the above embodiment and has the same effect as the battery, it will not be described in detail here.

[0071] Although the embodiments of the present invention are 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, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery cover assembly, characterized in that: include: A cover plate body, wherein the cover plate body is provided with an explosion-proof mechanism; A lower insulating member, the lower insulating member is connected to the cover plate body, the lower insulating member is provided with at least one mounting groove, and the mounting groove opens toward the cover plate body; At least one stopper is interference fit in the installation groove, and the orthographic projection of the stopper on the cover body does not completely overlap with the explosion-proof mechanism; the stopper is made of high temperature resistant material.

2. The battery cover assembly according to claim 1, characterized in that: At least two side walls of the stopper are protrudingly provided with interference ribs, and the interference ribs are interference-fitted with the inner wall of the mounting groove, and the interference dimension is E, 0.2mm≤E≤0.7mm.

3. The battery cover assembly according to claim 2, characterized in that: The width of the interference rib is A, 0.5mm≤A≤1.5mm, and / or, the length of the interference rib is B, 5mm≤B≤10mm, and / or, the thickness of the interference rib protruding from the side wall of the stopper is C, 0.3mm≤C≤0.8mm.

4. The battery cover assembly according to claim 3, characterized in that: An angle between a length extension direction of the interference rib and a thickness direction of the cover plate body is in a range of 0° to 30°.

5. The battery cover assembly according to claim 1 or 2, characterized in that: The explosion-proof mechanism includes an explosion-proof valve. The stopper is disposed between the explosion-proof valve and the lower insulating member. Along the width direction of the cover body, the width of the explosion-proof valve is W1, the width of the stopper is W2, and W2≥W1.

6. The battery cover assembly according to claim 1 or 2, characterized in that: A side wall of the stopper is provided with a plurality of interference ribs, and a distance between adjacent interference ribs is D, 5mm≤D≤10mm.

7. The battery cover assembly according to claim 1 or 2, characterized in that: The stopper is a block-shaped structure, and the cross section of the stopper includes a rectangle or a T-shape; Alternatively, the stopper is a frame structure, and the stopper is provided with a first liquid passage hole penetrating two opposite side walls in at least one direction.

8. The battery cover assembly according to claim 1 or 2, characterized in that: The bottom wall of the mounting groove of the lower insulating member is provided with a second liquid passage hole penetrating through the lower insulating member.

9. A battery, characterized in that: include: A housing having a receiving cavity with at least one end open; A pole group, the pole group is arranged in the accommodating cavity of the shell; The battery cover assembly according to any one of claims 1 to 8, wherein the battery cover assembly is arranged at the open end of the shell and is used to encapsulate the electrode group in the shell.

10. A battery pack, characterized in that: A battery comprising the battery of claim 9.

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