Cover plate structure and battery

Abstract

The utility model relates to the technical field of batteries, and discloses a cover plate structure and a battery, the cover plate structure comprises a cover plate body, the material of the cover plate body comprises steel; a circumferential limiting part is formed in at least partial area of the circumferential edge of the cover plate body, and the circumferential limiting part is suitable for abutting against the inner wall surface of the shell; an axial limiting part is further formed on the cover plate body, and the axial limiting part is suitable for abutting against the top face, in the axial direction, of the shell. According to the cover plate structure provided by the utility model, the cover plate body can abut against the inner wall surface of the shell, so that the cover plate body plays a role in supporting the shell, the circumferential limiting part can be in matched contact with the inner wall surface of the shell conveniently after the cover plate structure is mounted in the shell, the cover plate structure is prevented from displacing in the shell, and the service life of the shell is prolonged. And the situation that the shell is concave inwards when pressed by a tool is avoided, the situation that the steel cover plate structure is matched in a staggered mode is avoided, and the welding yield is guaranteed.

Description

Technical Field

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

[0002] In the field of power battery technology, the current mainstream battery cell shells are made of aluminum. The tensile strength of aluminum shells is 100Mpa to 250Mpa, and the compressive strength of aluminum shells with a wall thickness of 0.5mm is about 1.3Mpa to 1.6Mpa. However, due to insufficient compressive strength, aluminum shells are prone to rupture, causing battery cell fire and explosion. On the contrary, the strength of steel shells is much higher than that of aluminum shells, which can better solve the problem of low strength of aluminum shells and rupture when the battery cell is under thermal runaway.

[0003] In order to pursue energy density, the steel shell needs to be thinner than the aluminum shell to be equal in weight to the 0.5mm or 0.35mm thick aluminum shell. However, it is more difficult to match the thinner shell with the cover plate, and it has high requirements for tooling, welding and precision, and there are low yields, cold welding and other phenomena. The steel cover plate is thin, and if there is not enough limiter to support the shell, the shell will be concave during the tooling press, which can easily lead to misalignment of the steel cover plate, poor welding, or matching difficulties. Utility Model Content

[0004] In view of this, the utility model provides a cover plate structure and a battery to solve the problem that when a thin steel shell is assembled with the cover plate, the shell is easily concave due to lack of support, resulting in misalignment.

[0005] In a first aspect, the utility model provides a cover plate structure, including a cover plate body, wherein the material of the cover plate body includes steel;

[0006] A circumferential limit portion is formed in at least a portion of the circumferential edge of the cover body, and the circumferential limit portion is suitable for abutting against the inner wall surface of the shell;

[0007] The cover plate body is also formed with an axial limiting portion, which is suitable for abutting against the top surface of the shell along the axial direction.

[0008] Beneficial effect: The cover plate structure provided by the utility model forms a circumferential limiting portion on at least part of the circumferential edge of the cover plate body, so that the circumferential limiting portion is suitable for abutting against the inner wall surface of the shell, so that the cover plate body can abut against the inner wall surface of the shell, so that the cover plate body can play a supporting role on the shell, and after the cover plate structure is installed into the shell, the circumferential limiting portion can be matched with the inner wall surface of the shell to prevent the cover plate structure from being displaced in the shell, avoid the shell from being concave when the tooling is pressed, and avoid the misalignment of the steel cover plate structure, thereby ensuring the welding yield. The cover plate body is also formed with an axial limiting portion, which is suitable for abutting against the top surface of the shell along the axial direction; the axial limiting portion can prevent the cover plate structure from axial displacement, prevent the cover plate structure from being partially warped or partially concave at the opening of the shell, and ensure the accurate alignment of the cover plate structure and the shell in the subsequent welding stage, which is convenient for connection and fixation, thereby ensuring the sealing effect.

[0009] In an optional embodiment, the circumferential edge of the cover plate body is recessed to form a groove along a plane perpendicular to the cover plate body; a side wall of the groove away from the center line of the cover plate body forms a circumferential limiting portion.

[0010] In an optional embodiment, the axial limiting portion is formed by flanging a side of the circumferential limiting portion away from the center line of the cover plate body.

[0011] In an optional embodiment, the circumferential limiting portion is continuously arranged around the circumferential edge of the cover plate body.

[0012] Beneficial effect: By continuously arranging the circumferential limiting portion around the circumferential edge of the cover plate body, the circumferential limiting portion can be kept in continuous abutment with the inner wall surface of the shell, thereby ensuring the abutment effect.

[0013] In an optional embodiment, a yielding portion is formed at the corner of the axial limiting portion and the circumferential limiting portion, so that the axial limiting portion and the circumferential limiting portion are in contact with the shell surface at the same time.

[0014] Beneficial effect: The cover plate structure provided by the utility model forms a yielding portion at the corner of the axial limiting portion and the circumferential limiting portion, so that the axial limiting portion and the circumferential limiting portion are in contact with the shell surface at the same time; thereby eliminating the R angle generated at the bending portion when the cover plate structure is formed, preventing interference caused by the R angle when the cover plate structure and the shell are adapted, so that the shell with right-angled edges can fit closely with the cover plate structure, which is more conducive to the adaptation of the shell cover, avoids local warping, solves the problem of welding cold welds, and improves the welding yield.

[0015] In an optional embodiment, the giving way portion is formed by a partial depression of the wall surface of the cover plate body located at the circumferential limiting portion; the depressed cross section of the giving way portion is triangular, semicircular or trapezoidal.

[0016] In an optional embodiment, along a direction perpendicular to the plane where the circumferential limiting portion is located, the distance between the wall surface of the circumferential limiting portion and the end surface of the axial limiting portion is D, and satisfies 1 / 2M≤D≤M, where M is the wall thickness of the shell.

[0017] Beneficial effects: along the direction perpendicular to the plane where the circumferential limit portion is located, the distance D between the wall surface of the circumferential limit portion and the end surface of the axial limit portion, that is, the width of the axial limit portion; since the axial limit portion and the top surface of the shell are overlapped, by limiting D≤M, it is possible to avoid the circumferential edge of the shell structure protruding from the outer surface of the shell, thereby avoiding interference with other structures; and by limiting 1 / 2M≤D, the overlap area between the axial limit portion and the top surface of the shell can be guaranteed, thereby avoiding poor overlap caused by dimensional errors.

[0018] In an optional embodiment, the cover plate structure further includes a pole and / or an explosion-proof valve arranged on the cover plate body.

[0019] In a second aspect, the utility model further provides a battery, comprising a shell, and the cover plate structure as described above; the cover plate structure is arranged to cover the opening of the shell.

[0020] In an optional embodiment, the material of the shell includes steel.

[0021] Since the battery includes a cover plate structure, it has the same effect as the cover plate structure and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] 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.

[0023] Figure 1 It is a schematic diagram of the cover plate structure of the utility model;

[0024] Figure 2 It is a top view of the cover body of the utility model;

[0025] Figure 3 It is a cross-sectional schematic diagram of the cover plate body of the utility model;

[0026] Figure 4 for Figure 3 Enlarged view of point A in the middle;

[0027] Figure 5 A schematic diagram of a cover body provided with a yielding portion;

[0028] Figure 6 This is a schematic diagram of the matching state of the cover body and the shell of the utility model;

[0029] Figure 7 It is a schematic diagram of the interference area between the cover body without the relief portion and the shell.

[0030] Description of reference numerals:

[0031] 1. Pole; 2. Cover plate body; 21. Groove; 22. Circumferential limiting portion; 23. Axial limiting portion; 24. Yield portion; 3. Explosion-proof valve; 4. Shell; 6. Interference area. DETAILED DESCRIPTION

[0032] 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.

[0033] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] Combine the following Figures 1 to 7 , describing an embodiment of the utility model.

[0037] According to an embodiment of the present utility model, on one hand, a cover plate structure is provided, including a cover plate body 2, wherein the material of the cover plate body 2 includes steel;

[0038] A circumferential limit portion 22 is formed in at least a portion of the circumferential edge of the cover body 2, and the circumferential limit portion 22 is suitable for abutting against the inner wall surface of the shell 4;

[0039] The cover body 2 is further formed with an axial limiting portion 23 , which is suitable for abutting against the top surface of the housing 4 along the axial direction.

[0040] Since the steel cover plate is relatively thin, most of them are steel plates with a thickness of less than 1mm. If a step is punched on a 1mm thick steel plate, the step height will be too small. If there is not enough limiting part to support the shell, the shell will be concave during the press installation of the tooling, which may easily lead to misalignment of the steel cover plate, poor welding, or matching difficulties.

[0041] The cover plate structure provided by the embodiment of the utility model is provided with a circumferential limiting portion 22 formed at least in part of the circumferential edge of the cover plate body 2, so that the circumferential limiting portion 22 is suitable for abutting against the inner wall surface of the shell 4, so that the cover plate body 2 can abut against the inner wall surface of the shell 4, so that the cover plate body 2 can play a supporting role on the shell 4, and after the cover plate structure is installed into the shell, the circumferential limiting portion 22 can be matched with the inner wall surface of the shell 4 to prevent the cover plate structure from being displaced in the shell 4, and the shell 4 from being concave during the tooling press, and the steel cover plate structure from being misaligned, thereby ensuring the welding yield. The cover plate body 2 is also formed with an axial limiting portion 23, which is suitable for abutting against the top surface of the shell 4 along the axial direction; the axial limiting portion 23 can prevent the cover plate structure from being axially displaced, and prevent the cover plate structure from being partially warped or partially concave at the opening of the shell 4, and can ensure the accurate alignment of the cover plate structure and the shell 4 in the subsequent welding stage, which is convenient for connection and fixing, thereby ensuring the sealing effect.

[0042] In some embodiments, in combination Figure 1 As shown, along a plane perpendicular to the cover body 2 , the circumferential edge of the cover body 2 is recessed to form a groove 21 ; a side wall of the groove 21 away from the center line of the cover body 2 forms a circumferential limiting portion 22 .

[0043] The groove 21 may be formed by punching.

[0044] Due to the limited forming process capability of steel material, the cover body 2 forms an R angle at the corner on the side away from the groove 21. Therefore, when the cover body 2 is installed into the shell 4, the R angle can play a guiding role, which facilitates the installation of the cover body 2. After entering the shell, the circumferential limit portion 22 is in contact with the inner wall surface of the shell 4, which can prevent the cover structure from being displaced in the shell 4; during welding, since the welding tooling will press the outer wall of the shell 4 around, the circumferential limit portion 22 supports the shell 4, preventing the shell 4 from being concave when the tooling is pressed, thereby preventing the cover body 2 from being displaced, ensuring the welding yield, and reducing the requirements for the welding tooling.

[0045] Furthermore, the axial limiting portion 23 is suitable for abutting against the top surface of the shell 4 along the axial direction. When entering the shell, the axial limiting portion 23 fits with the top surface of the shell 4, and the axial limiting portion 23 prevents the cover plate structure from excessively entering the shell axially; after entering the shell, the axial limiting portion 23 is supported by the top surface of the shell 4 along the axial direction, and the axial limiting portion 23 can prevent the cover plate structure from axial displacement; during welding, the axial limiting portion 23 can ensure that the cover plate structure is accurately aligned with the shell 4, which is convenient for connection and fixation, thereby ensuring the sealing effect.

[0046] In some embodiments, in combination Figure 4 As shown, the axial limiting portion 23 is formed by flanging the side of the circumferential limiting portion 22 away from the center line of the cover plate body 2. The axial limiting portion 23 and the circumferential limiting portion 22 form a continuous integrated structure, which is convenient for stamping.

[0047] In some embodiments, in combination Figure 2 As shown, the circumferential limiting portion 22 is continuously arranged around the circumferential edge of the cover plate body 2 .

[0048] By continuously arranging the circumferential limiting portion 22 around the circumferential edge of the cover plate body 2 , the circumferential limiting portion 22 can be kept in continuous contact with the inner wall surface of the shell 4 , thereby ensuring the contact effect.

[0049] In some embodiments, in combination Figure 5 , Figure 6 As shown, a yielding portion 24 is formed at the corner between the axial limiting portion 23 and the circumferential limiting portion 22 so that the axial limiting portion 23 and the circumferential limiting portion 22 are in surface contact with the housing 4 at the same time.

[0050] Combination Figure 7As shown, in the actual manufacturing process of the cover plate structure, since the cover plate structure and the shell are both made of thin steel, the molding process capacity of the cover plate structure is limited, and a right angle cannot be formed at the connection between the axial limit portion 23 and the circumferential limit portion 22, and a larger R angle is usually formed. At this time, if the cover plate structure is covered on the shell 4, due to the existence of the R angle, an interference area 6 will be generated when the shell cover is adapted. The interference area 6 will cause the cover plate structure to be installed in the shell. The matching position of the two will cause warping, resulting in the cover plate structure and the shell 4 cannot be fully fitted, or the edge of the shell is turned outward, which is easy to produce a large number of cold welds and affect the welding yield.

[0051] The cover plate structure provided by the embodiment of the utility model has a yielding portion 24 formed at the corner of the axial limiting portion 23 and the circumferential limiting portion 22, so that the axial limiting portion 23 and the circumferential limiting portion 22 are in contact with the surface of the shell 4 at the same time; thereby eliminating the R angle generated at the bending portion when the cover plate structure is formed, preventing interference caused by the R angle when the cover plate structure and the shell 4 are adapted, so that the shell with right-angled sides can be closely matched with the cover plate structure, which is more conducive to the adaptation of the shell cover, avoids local warping, solves the problem of welding cold welds, and improves the welding yield.

[0052] In some embodiments, in combination Figure 5 As shown, the relief portion 24 is formed by a partial depression of the wall surface of the cover plate body 2 located at the circumferential limiting portion 22; the depressed cross section of the relief portion 24 is triangular, semicircular or trapezoidal.

[0053] The shape of the concave cross section of the relief portion 24 is not limited, as long as it does not interfere with the right-angled side of the housing.

[0054] In some embodiments, in combination Figure 4 As shown, along the direction perpendicular to the plane where the circumferential limiting portion 22 is located, the distance between the wall surface of the circumferential limiting portion 22 and the end surface of the axial limiting portion 23 is D, and satisfies 1 / 2M≤D≤M, where M is the wall thickness of the shell 4.

[0055] Along the direction perpendicular to the plane where the circumferential limit portion 22 is located, the distance D between the wall surface of the circumferential limit portion 22 and the end surface of the axial limit portion 23, that is, the width of the axial limit portion 23; since the axial limit portion 23 forms an overlap with the top surface of the shell 4, by limiting D≤M, it is possible to avoid the circumferential edge of the shell structure protruding from the outer surface of the shell 4, thereby avoiding interference with other structures; and by limiting 1 / 2M≤D, the overlap area between the axial limit portion 23 and the top surface of the shell 4 can be guaranteed, thereby avoiding poor overlap caused by dimensional errors.

[0056] In some embodiments, in combination Figure 1 As shown, the cover plate structure further includes a pole 1 and / or an explosion-proof valve 3 arranged on the cover plate body 2 .

[0057] According to an embodiment of the present utility model, on the other hand, a battery is provided, including a housing 4 and the cover structure as described above; the cover structure is covered at the opening of the housing 4 .

[0058] The battery provided by the embodiment of the utility model has a circumferential limiter 22 formed on at least part of the circumferential edge of the cover body 2, so that the circumferential limiter 22 is suitable for abutting against the inner wall surface of the shell 4, so that the cover body 2 can abut against the inner wall surface of the shell 4, so that the cover body 2 can support the shell 4, and after the cover structure is installed in the shell, the circumferential limiter 22 can be matched with the inner wall surface of the shell 4 to prevent the cover structure from being displaced in the shell 4, and prevent the shell 4 from being concave during the tooling press, and avoid the situation of misalignment of the steel cover structure, so as to ensure the welding yield. The cover body 2 is also formed with an axial limiter 23, which is suitable for abutting against the top surface of the shell 4 along the axial direction; the axial limiter 23 can prevent the cover structure from being axially displaced, and prevent the cover structure from being partially warped or partially concave at the opening of the shell 4, so that the cover structure can be accurately aligned with the shell 4 in the subsequent welding stage, which is convenient for connection and fixing, and thus ensures the sealing effect.

[0059] In some embodiments, the material of the housing 4 includes steel.

[0060] The strength of the steel shell is much higher than that of the aluminum shell, which can better solve the problem of low strength of the aluminum shell and rupture when the battery cell experiences thermal runaway.

[0061] The shell 4 and the cover plate structure are made of the same material, which facilitates welding.

[0062] Obviously, the above embodiments are only examples for clear explanation, and are not intended to limit the implementation methods. Although the embodiments of the present utility model 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 utility model, and such modifications and variations are all within the scope defined by the present utility model.

Claims

1. A cover plate structure, characterized in that: It includes a cover plate body, wherein the material of the cover plate body includes steel; A circumferential limit portion is formed in at least a portion of the circumferential edge of the cover body, and the circumferential limit portion is suitable for abutting against the inner wall surface of the shell; The cover plate body is further formed with an axial limiting portion, and the axial limiting portion is suitable for abutting against the top surface of the shell along the axial direction.

2. The cover plate structure according to claim 1, characterized in that: Along a plane perpendicular to the cover body, the circumferential edge of the cover body is recessed to form a groove; a side wall of the groove away from the center line of the cover body forms the circumferential limiting portion.

3. The cover plate structure according to claim 2, characterized in that: The axial limiting portion is formed by flanging a side of the circumferential limiting portion away from the center line of the cover plate body.

4. The cover plate structure according to claim 1, characterized in that: The circumferential limiting portion is continuously arranged around the circumferential edge of the cover plate body.

5. The cover plate structure according to claim 1, characterized in that: A yielding portion is formed at a corner of the axial limiting portion and the circumferential limiting portion, so that the axial limiting portion and the circumferential limiting portion are in contact with the housing surface at the same time.

6. The cover plate structure according to claim 5, characterized in that: The giving way portion is formed by a partial depression of the wall surface of the cover plate body located at the circumferential limiting portion; the depressed cross section of the giving way portion is triangular, semicircular or trapezoidal.

7. The cover plate structure according to any one of claims 1 to 6, characterized in that: Along a direction perpendicular to the plane where the circumferential limiting portion is located, the distance between the wall surface of the circumferential limiting portion and the end surface of the axial limiting portion is D, and satisfies 1 / 2M≤D≤M, where M is the wall thickness of the shell.

8. The cover plate structure according to any one of claims 1 to 6, characterized in that: The cover plate structure further comprises a pole and / or an explosion-proof valve arranged on the cover plate body.

9. A battery, characterized in that: It comprises a shell, and a cover plate structure as described in any one of claims 1 to 8; the cover plate structure is arranged to cover the opening of the shell.

10. The battery according to claim 9, characterized in that The material of the shell includes steel.

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