Shell structure and button cell

Abstract

The utility model belongs to the technical field of batteries, and particularly relates to a shell structure which comprises an insulating glue layer, a cover plate and a shell, a groove for placing the battery cell is formed in the shell, and the cover plate covers the shell to seal an opening of the groove; the cover plate is provided with a first contact surface, and the opening end of the shell is provided with a second contact surface opposite to the first contact surface; the insulating rubber layer is annular and is bonded between the first contact surface and the second contact surface, so that the cover plate can be separated from the shell when the component force of the thrust applied to the cover plate along the direction perpendicular to the cover plate is greater than a preset thrust value; when the use environment temperature of the shell structure is 20-30 DEG C, the preset thrust value is 100-150N; and when the use environment temperature of the shell structure is 70-90 DEG C, the preset thrust value is 80-120N. According to the shell structure and the button cell provided by the embodiment of the utility model, the first contact surface and the second contact surface are respectively adhered to the surfaces of the two sides of the insulating glue layer, and when the preset thrust value is compounded with a value at a related temperature, the cover plate is difficult to separate from the shell.

Description

Technical Field

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

[0002] In a button battery, a general cover assembly includes a pole, insulating glue and a cover. The pole is inserted into the cover, and the insulating glue seals the pole and the cover. After the cover, insulating glue and pole are combined, the cover is welded to the shell in which the battery cell has been placed to form a button battery.

[0003] Currently, many manufacturers are trying to adopt a poleless structure. The shell structure of the battery includes a cover plate, insulating glue and a shell. However, the shell and the cover plate can no longer be welded, but instead bonded with insulating glue. However, during use, the connection strength between the cover plate and the shell is often insufficient, especially when the glue layer is easily detached under high temperature use, resulting in leakage of the battery cell, which seriously affects the performance of the battery cell. Summary of the invention

[0004] The technical problem to be solved by the utility model is: to provide a shell structure and a button battery in view of the problem that the connection strength between the cover plate and the shell is insufficient and the glue layer is easy to fall off during use.

[0005] In order to solve the above technical problems, on the one hand, the embodiment of the utility model provides a housing structure, including an insulating rubber layer, a cover plate and a housing;

[0006] The housing is provided with a groove for placing the battery cell, and the cover plate covers the housing to close the opening of the groove;

[0007] The cover plate is provided with a first contact surface, and the opening end of the shell has a second contact surface opposite to the first contact surface;

[0008] The insulating adhesive layer is annular and is bonded between the first contact surface and the second contact surface, so that when the component force of the thrust applied to the cover plate in a direction perpendicular to the cover plate is greater than a preset thrust value, the cover plate can be separated from the shell;

[0009] When the ambient temperature of the shell structure is 20-30°C, the preset thrust value is 100-150N;

[0010] When the ambient temperature of the shell structure is 70-90°C, the preset thrust value is 80-120N.

[0011] Optionally, the insulating adhesive layer is bonded to the first contact surface and the second contact surface by hot pressing, and the ratio of the thickness of the insulating adhesive layer after hot pressing to the thickness before hot pressing is 0.4-0.7.

[0012] Optionally, both the first contact surface and the second contact surface are rough surfaces.

[0013] Optionally, an end surface of the open end of the shell constitutes the second contact surface;

[0014] The surface of the cover plate that is opposite to the end surface of the opening end of the housing constitutes the first contact surface.

[0015] Optionally, the cover plate includes a plate body and a coating, wherein the coating is applied to a surface of the plate body on one side facing the insulating adhesive layer and is bonded to the insulating adhesive layer;

[0016] The end surface of the opening end of the shell constitutes the second contact surface;

[0017] The surface of the coating layer that is away from the plate body constitutes the first contact surface.

[0018] Optionally, the coating fully coats the surface of the board body on one side facing the insulating adhesive layer.

[0019] Optionally, the coating is ring-shaped.

[0020] Optionally, the open end of the shell extends outward and protrudes from the outer surface of the side wall of the shell to form a ring edge;

[0021] The ring edge is parallel to the cover plate, and the surface of the ring edge close to the cover plate constitutes the second contact surface; the surface of the cover plate opposite to the ring edge constitutes the first contact surface.

[0022] Optionally, the inner circle of the insulating rubber layer extends toward the center of the cover plate and extends into the groove;

[0023] The outer peripheral surface of the insulating rubber layer is flush with the outer peripheral surface of the cover plate.

[0024] On the other hand, an embodiment of the present invention further provides a button-type battery, comprising the above-mentioned shell structure.

[0025] According to the shell structure and button battery of the embodiment of the utility model, the two side surfaces of the insulating adhesive layer are respectively bonded to the first contact surface and the second contact surface. When the ambient temperature is at room temperature (20-30°C), the connection strength between the cover plate and the shell is 100-150N, making it difficult for the cover plate to be separated from the shell, that is, the insulating adhesive layer is difficult to fall off. Similarly, when the ambient temperature is 70-90 degrees, the connection strength between the cover plate and the shell is 80-120N, and the insulating adhesive layer is difficult to fall off.

[0026] In addition, when both the first contact surface and the second contact surface are rough surfaces, the bonding area of ​​the insulating adhesive layer increases, and compared with the smooth first contact surface and the second contact surface, the bonding strength increases, thereby reducing the phenomenon of the insulating adhesive layer falling off. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the housing structure provided by the first embodiment of the utility model;

[0028] Figure 2 yes Figure 1 A magnified schematic diagram of part A;

[0029] Figure 3 It is a schematic diagram of the positions of the first contact surface and the second contact surface provided by the first embodiment of the utility model;

[0030] Figure 4 It is an overall schematic diagram of a button battery provided in the fourth embodiment of the utility model.

[0031] The reference numerals in the specification are as follows:

[0032] 1. Shell; 11. Groove; 12. Ring edge; 13. First contact surface; 2. Cover plate; 21. Second contact surface; 3. Insulating rubber layer; 4. Battery core. DETAILED DESCRIPTION

[0033] In order to make the technical problems, technical solutions and beneficial effects solved by the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0034] First embodiment

[0035] like Figure 1 and Figure 2As shown, the housing structure provided by the first embodiment of the utility model includes an insulating rubber layer 3, a cover plate 2 and a housing 1; the housing 1 is cylindrical, the groove 11 is cylindrical, the cover plate 2 is a circular plate, the insulating rubber layer is annular, the housing 1 is provided with a groove 11 for placing the battery cell 4, and the cover plate 2 covers the housing 1 to close the opening of the groove 11; the cover plate 2 has a first contact surface 13, and the open end of the housing 1 has a second contact surface 21 opposite to the first contact surface 13, and the first contact surface 13 and the second contact surface 21 are both rough The insulating adhesive layer 3 is used for the insulation of the cover plate 2 and the shell 1. The insulating adhesive layer 3 is arranged between the first contact surface 13 and the second contact surface 21. The insulating adhesive layer 3 adheres the first contact surface 13 and the second contact surface 21, so that the cover plate 2 can be separated from the shell 1 when subjected to a preset thrust. The preset thrust is a force perpendicular to the surface of the cover plate 2. However, in actual situations, the force exerted on the cover plate is not necessarily perpendicular to the cover plate. Therefore, when the force exerted on the cover plate is not perpendicular to the cover plate, the thrust exerted on the cover plate in the component perpendicular to the cover plate is the preset thrust. When the ambient temperature of the shell structure is 20-30℃, the preset thrust value is 100-150N; when the ambient temperature of the shell structure is 70-90℃, the preset thrust value is 80-120N.

[0036] More specifically, when the shell structure is used in an environment of 25°C, the preset thrust is 100N; when the shell structure is used in an environment of 60°C, the preset thrust is 80N. When the ambient temperature is at room temperature (20-30°C), the connection strength between the cover and the shell is 100-150N, making it difficult for the cover to detach from the shell, that is, the insulating rubber layer is difficult to fall off, thereby ensuring the connection strength between the cover and the shell. Similarly, when the ambient temperature is 70-90 degrees, the connection strength between the cover and the shell is 80-120N, and the insulating rubber layer is also difficult to fall off.

[0037] Reference Figure 3 , the first contact surface 13 on the cover plate 2 and the second contact surface 21 on the shell 1 can be cleaned and processed by using an acid solution. On the one hand, the acid solution can remove dirt and oxides on the surface, and can also increase the surface roughness, thereby improving the surface roughness. When the first contact surface and the second contact surface are both rough surfaces, naturally, the bonding area of ​​the insulating adhesive layer increases, and compared with the smooth first contact surface and the second contact surface, the bonding strength increases, thereby reducing the phenomenon of the insulating adhesive layer falling off. Of course, a high-pressure fluid can also be used to spray abrasives to the position of the first contact surface 13 and the position of the second contact surface 21, so that the first contact surface 13 and the second contact surface 21 are processed into rough surfaces.

[0038] After the surface of the cover plate 2 and the shell 1 is roughened, the insulating rubber layer 3 is first laid flat on the upper extension surface of the steel shell, and the positive pole ear of the winding core is respectively connected to one of the shell 1 and the cover plate 2 by welding, and the negative pole ear is welded to the other of the shell 1 and the cover plate 2. After the liquid is injected, the cover plate 2, the shell 1 and the insulating rubber layer 3 are hot-pressed and compounded together by a jig, and the insulating rubber layer 3 is hot-pressed to bond the first contact surface 13 and the second contact surface 21. The ratio of the thickness of the insulating rubber layer 3 after extrusion to the thickness before extrusion is 0.4-0.7. The specific parameters of the hot pressing process in this embodiment are as follows: temperature 120-175°C, time 2-10S, and the compression amount of the rubber layer thickness 40%-70%, thereby obtaining a finished battery cell 4.

[0039] In this embodiment, the opening end of the shell 1 extends outward to protrude from the outer peripheral surface of the side wall of the shell 1 to form a ring edge 12; the ring edge 12 is parallel to the cover plate 2, and the second contact surface 21 is the surface of the ring edge 12 close to the cover plate 2. The surface of the cover plate 2 opposite to the end surface of the opening end of the shell 1 constitutes the first contact surface 13. The insulating adhesive layer 3 is arranged between the ring edge 12 and the cover plate 2. The upper surface of the ring edge 12 is roughened, and the lower surface of the cover plate 2 is roughened, and the insulating adhesive layer 3 is added between the ring edge 12 and the cover plate 2. Compared with not setting the ring edge 12, the setting of the ring edge 12 increases the area of ​​the second contact surface 21, thereby increasing the second contact surface 21 and the first contact surface 13, so that the bonding area of ​​the insulating adhesive layer 3 is increased, which can increase the upper limit of the bonding force of the insulating adhesive layer 3.

[0040] In this embodiment, the housing 1 is a stainless steel housing, and the cover plate 2 is an aluminum plate or a stainless steel plate.

[0041] Referring to the figure, it can be seen that the insulating rubber layer 3 in this embodiment extends toward the center of the cover plate 2, so that the inner ring surface of the insulating rubber layer 3 protrudes from the inner wall of the groove 11, that is, the inner ring of the insulating rubber layer 3 extends into the groove, and the outer peripheral surface of the insulating rubber layer 3 is flush with the outer peripheral surface of the cover plate, and the outer peripheral surface of the cover plate is flush with the outer peripheral surface of the ring edge. The upper and lower surfaces of the insulating rubber layer 3 are both larger than the area of ​​the first contact surface 13 and the area of ​​the second contact surface 21, so that the housing 1 and the cover plate 2 are completely isolated, reducing the occurrence of short circuit phenomenon.

[0042] Second embodiment

[0043] The housing structure of the second embodiment of the utility model is different from that of the first embodiment in that the end surface of the opening end of the housing constitutes the second contact surface, and the surface of the cover plate opposite to the end surface of the opening end of the housing constitutes the first contact surface.

[0044] In this embodiment, the open end of the shell does not need to extend outward, and the structure is simpler.

[0045] Third embodiment

[0046] In the shell structure of the third embodiment of the utility model, the cover plate includes a plate body and a coating arranged from top to bottom, and the coating is arranged between the insulating rubber layer and the plate body. The end surface of the opening end of the shell constitutes the second contact surface; the surface of the coating away from the plate body constitutes the first contact surface.

[0047] Wherein, the coating is formed by coating the entire lower surface of the plate body. In some embodiments, the coating is coated entirely on the lower surface of the plate body. In some embodiments, the coating is annular, and the orthographic projection of the coating on the lower surface of the cover plate coincides with the orthographic projection of the end face of the opening end of the shell on the lower surface of the cover plate. Of course, in other embodiments, the coating is annular, and the orthographic projection of the coating on the lower surface of the cover plate is located within the orthographic projection of the end face of the opening end of the shell on the lower surface of the cover plate. Of course, the orthographic projection of the coating on the lower surface of the cover plate is located outside the orthographic projection of the end face of the opening end of the shell on the lower surface of the cover plate. The coating in this embodiment can be adjusted according to actual needs.

[0048] In this embodiment, the coating is a rubber coating. The surface of the rubber coating can also be roughened so that the friction coefficient of the lower surface of the rubber coating is increased. In other embodiments, the coating can be a coating with a high friction coefficient, such as a polymer coating, more specifically, an epoxy resin coating, an acrylic coating, etc.

[0049] Fourth embodiment

[0050] Reference Figure 4 The fourth embodiment of the utility model provides a button battery, comprising a battery cell 4 and a shell 1 structure as described in any one of the above embodiments. The battery cell 4 is built into the groove 11, the positive electrode of the battery cell 4 is electrically connected to one of the cover plate 2 and the shell 1, and the negative electrode of the battery cell 4 is electrically connected to the other of the cover plate 2 and the shell 1.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A housing structure, characterized in that: It includes an insulating rubber layer, a cover plate and a shell; The housing is provided with a groove for placing the battery cell, and the cover plate covers the housing to close the opening of the groove; The cover plate is provided with a first contact surface, and the opening end of the shell has a second contact surface opposite to the first contact surface; The insulating adhesive layer is annular and is bonded between the first contact surface and the second contact surface, so that when the component force of the thrust applied to the cover plate in a direction perpendicular to the cover plate is greater than a preset thrust value, the cover plate can be separated from the shell; When the ambient temperature of the shell structure is 20-30°C, the preset thrust value is 100-150N; When the ambient temperature of the shell structure is 70-90°C, the preset thrust value is 80-120N.

2. The housing structure according to claim 1, characterized in that: The insulating adhesive layer is bonded to the first contact surface and the second contact surface by hot pressing, and the ratio of the thickness of the insulating adhesive layer after hot pressing to the thickness before hot pressing is 0.4-0.

7.

3. The housing structure according to claim 1, characterized in that: The first contact surface and the second contact surface are both rough surfaces.

4. The housing structure according to claim 1, characterized in that: The end surface of the opening end of the shell constitutes the second contact surface; The surface of the cover plate that is opposite to the end surface of the opening end of the housing constitutes the first contact surface.

5. The housing structure according to claim 4, characterized in that: The cover plate comprises a plate body and a coating, wherein the coating is applied to a surface of the plate body on one side facing the insulating adhesive layer and is bonded to the insulating adhesive layer; The end surface of the opening end of the shell constitutes the second contact surface; The surface of the coating layer that is away from the plate body constitutes the first contact surface.

6. The housing structure according to claim 5, characterized in that: The coating is fully coated on the surface of the plate body on one side facing the insulating adhesive layer.

7. The housing structure according to claim 5, characterized in that: The coating is in the shape of a ring.

8. The housing structure according to claim 1, characterized in that: The open end of the shell extends outward and protrudes from the outer surface of the side wall of the shell to form a ring edge; The ring edge is parallel to the cover plate, and the surface of the ring edge close to the cover plate constitutes the second contact surface; the surface of the cover plate opposite to the ring edge constitutes the first contact surface.

9. The housing structure according to claim 1, characterized in that: The inner circle of the insulating rubber layer extends toward the center of the cover plate and extends into the groove; The outer peripheral surface of the insulating rubber layer is flush with the outer peripheral surface of the cover plate.

10. A button battery, characterized in that: The invention comprises a shell structure as described in any one of claims 1 to 9.

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