Shell of single battery, single battery and battery pack

Abstract

The shell comprises a cover body and a shell body, the shell body comprises an end plate and an annular body, the annular body is arranged around the edge of the end plate so as to enable the end plate and the annular body to define a mounting space with one open end, and the cover body is connected with the shell body so as to seal the open end of the mounting space. A groove structure is formed in the end plate, a first protruding structure protruding towards the interior of the installation space is further formed on the end plate, and the end wall, opposite to the cover body, of the first protruding structure is used for installing an anti-explosion structure. Therefore, according to the utility model, the groove structure and the first bulge structure are formed on the shell, the explosion-proof structure is arranged on the first bulge structure, and the residual electrolyte in the battery monomer is suitable for flowing into the groove structure, so that the residual electrolyte is prevented from immersing and corroding the explosion-proof structure, and the use reliability of the explosion-proof structure is ensured.

Description

Technical Field

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

[0002] In the related art, in order to ensure that the electrode group of the existing battery cell can be fully infiltrated by the electrolyte, the injection amount of the electrolyte will be slightly more than the adsorption amount of the electrode group, which may result in some residual electrolyte inside the battery cell. The residual electrolyte inside the battery cell flows to the bottom of the battery cell shell under the action of gravity, which can easily cause the residual electrolyte to immerse the explosion-proof structure provided at the bottom of the shell. Since the electrolyte has a certain corrosiveness, there is a risk of the electrolyte corroding the explosion-proof structure. In addition, since the electrolyte immerses the explosion-proof structure, it will also cause the exhaust pressure of the explosion-proof structure, so that the explosion-proof structure cannot work normally, thereby reducing the safety of the battery cell. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the utility model is to provide a battery cell housing to prevent residual electrolyte from immersing and corroding the explosion-proof structure, thereby ensuring the reliability of the explosion-proof structure.

[0004] The housing according to the utility model comprises:

[0005] The cover body and the shell body, the shell body includes an end plate and an annular body, the annular body is arranged around the edge of the end plate so that the end plate and the annular body define an installation space with one end open, the cover body is connected to the shell body to close the open end of the installation space, the end plate is formed with a groove structure, and the end plate is also formed with a first protrusion structure protruding toward the installation space, and the end wall opposite to the first protrusion structure and the cover body is used for installing an explosion-proof structure.

[0006] According to the shell of the utility model, the end plate is formed with a groove structure and a first protruding structure, and the explosion-proof structure is installed on the first protruding structure, so that the residual electrolyte inside the battery cell is suitable for flowing into the groove structure, avoiding the residual electrolyte from immersing and corroding the explosion-proof structure, thereby ensuring the reliability of the explosion-proof structure.

[0007] In some examples of the present invention, the groove structure is disposed adjacent to the first protrusion structure.

[0008] In some examples of the present invention, the end plate is also formed with a second protrusion structure protruding toward the installation space, the second protrusion structure is used to support the pole group of the battery cell, the second protrusion structure is spaced apart from the first protrusion structure, and a groove structure is formed between the second protrusion structure and the first protrusion structure.

[0009] In some examples of the present invention, a height of the second protruding structure protruding into the installation space is greater than a height of the first protruding structure protruding into the installation space.

[0010] In some examples of the present invention, the groove structure is located between the first protrusion structure and the annular body.

[0011] In some examples of the present invention, the groove structure is annular, and the groove structure is arranged around the first protrusion structure.

[0012] In some examples of the present invention, an end wall of the first protruding structure opposite to the cover body has a through hole for installing an explosion-proof structure.

[0013] In some examples of the present invention, the thickness of the end plate is H1, and the thickness of the annular body is H2, satisfying the relationship: H1 ≥ H2.

[0014] The battery cell according to the utility model comprises:

[0015] A housing, the housing being the housing mentioned above, and defining a mounting cavity in the housing;

[0016] The pole group is installed in the installation cavity;

[0017] An explosion-proof structure is installed on the shell.

[0018] The battery pack according to the utility model comprises:

[0019] A box body, wherein an assembly space is defined within the box body;

[0020] At least one battery cell, the battery cell is the above-mentioned battery cell, and the battery cell is installed in the assembly space.

[0021] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0023] Figure 1 is a schematic structural diagram of a battery cell according to an embodiment of the utility model;

[0024] Figure 2 yes Figure 1 Enlarged view of point A in the middle;

[0025] Figure 3 It is a schematic diagram of the partial structure of the shell according to an embodiment of the utility model.

[0026] Reference numerals:

[0027] Battery cell 1000; installation cavity 200; shell 100; cover 1; shell body 2; installation space 20; end plate 21; annular body 22; groove structure 30; first protrusion structure 31; second protrusion structure 32; through hole 33; explosion-proof structure 4. DETAILED DESCRIPTION

[0028] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0029] Reference below Figure 1-Figure 3 A shell 100 of a battery cell 1000 according to an embodiment of the utility model is described. The shell 100 includes a cover body 1 and a shell body 2. The shell body 2 includes an end plate 21 and an annular body 22. The annular body 22 is arranged around the edge of the end plate 21 so that the end plate 21 and the annular body 22 define an installation space 20 with one end open. The cover body 1 is connected to the shell body 2 to close the open end of the installation space 20. The end plate 21 is formed with a groove structure 30, and the end plate 21 is also formed with a first protrusion structure 31 protruding toward the installation space 20. The end wall of the first protrusion structure 31 opposite to the cover body 1 is used for installing an explosion-proof structure 4.

[0030] In some embodiments, Figure 1 As shown, the structure of the shell 100 is similar to a quadrangular prism structure, and accordingly, the cross-section of the annular body 22 is constructed as a rectangle. When the annular body 22 is connected to the end plate 21, the annular body 22 is connected to the end plate 21 around the edge of the end plate 21, so that the end plate 21 and the annular body 22 are connected to jointly define an installation space 20 with one end open.

[0031] like Figure 1 As shown, the battery cell 1000 is Figure 1 When placed in the middle direction, the first direction of the battery cell 1000 is Figure 1 In the Z direction shown in , when the cover body 1 is connected to the shell body 2, the cover body 1 and the end plate 21 are arranged opposite to each other along the first direction, and the cover body 1 closes the open end of the installation space 20, so that the cover body 1 and the shell 100 jointly define the installation cavity 200, and the pole group of the battery cell 1000 is installed in the installation cavity 200.

[0032] In some embodiments, Figure 1As shown, the electrode group is installed in the installation cavity 200. By injecting electrolyte into the installation cavity 200, the electrolyte will infiltrate the electrode group so that the electrode group can be used for electrochemical reaction. However, in some embodiments, in order to ensure that the electrode group can be fully infiltrated by the electrolyte, the injection amount of the electrolyte will be slightly more than the adsorption amount of the electrode group. Therefore, there may be some residual electrolyte in the installation cavity 200.

[0033] In some embodiments, Figure 1 As shown, the battery cell 1000 is Figure 1 The end plate 21 is placed in the middle direction, that is, the end plate 21 is located below the cover body 1, so the residual electrolyte flows to the end plate 21 under the action of gravity.

[0034] According to the end plate 21 of the embodiment of the utility model, the end plate 21 is formed with a groove structure 30 and a first protrusion structure 31. The residual electrolyte can flow into the groove structure 30 to avoid the residual electrolyte from being immersed in the explosion-proof structure 4 arranged on the first protrusion structure 31 for a long time. Since the electrolyte has a certain corrosiveness, the shell 100 according to the embodiment of the utility model can avoid the residual electrolyte from corroding the explosion-proof structure 4. In addition, if the residual electrolyte immerses the explosion-proof structure 4, it will affect the exhaust pressure of the explosion-proof structure 4, causing the explosion-proof structure 4 to fail to work normally, resulting in the gas in the installation cavity 200 unable to be discharged in time. Therefore, the shell 100 according to the embodiment of the utility model can effectively ensure the reliability of the use of the explosion-proof structure 4.

[0035] In some embodiments of the present invention, Figure 1 As shown, the groove structure 30 is arranged adjacent to the first protruding structure 31, which is conducive to the electrolyte located in the first protruding structure 31 to flow into the groove structure 30, thereby avoiding the electrolyte from being immersed in the explosion-proof structure 4 arranged in the first protruding structure 31 for a long time, thereby ensuring the reliability of the explosion-proof structure 4.

[0036] In some embodiments of the present invention, Figure 1 As shown, the end plate 21 may also be formed with a second protrusion structure 32 protruding toward the installation space 20, the second protrusion structure 32 is used to support the pole group of the battery cell 1000, the second protrusion structure 32 is spaced apart from the first protrusion structure 31, and a groove structure 30 is formed between the second protrusion structure 32 and the first protrusion structure 31.

[0037] In some embodiments, taking into account the processing technology, the connection between the end plate 21 and the annular body 22 forms an arc surface, and because the bottom wall and the side wall of the pole group form an angle, a second protrusion structure 32 is provided, and when the pole group is placed in the installation cavity 200, the second protrusion structure 32 is suitable for abutting against the bottom wall of the pole group, thereby avoiding interference between the connecting edge of the bottom wall and the side wall of the pole group and the connecting edge of the end plate 21 and the annular body 22, thereby avoiding deformation of the pole group, which is beneficial to ensuring the reliability of the pole group.

[0038] In addition, in the prior art, by providing a support plate between the pole group and the end plate, the connection edge of the bottom wall and the side wall of the pole group can be prevented from interfering with the connection edge of the end plate and the annular body. However, the support plate does not have high temperature resistance. Therefore, when the battery cell undergoes thermal runaway, the support plate is easily melted, causing the pole group to move toward the side of the explosion-proof structure to cover the explosion-proof structure, resulting in the explosion-proof structure being unable to open normally, causing the gas pressure in the installation cavity to increase, which may further cause the shell body to crack and leak.

[0039] Therefore, according to the shell 100 of the embodiment of the utility model, a second protruding structure 32 is formed by the end plate 21, and the second protruding structure 32 is used to support the pole group, so that the battery cell 1000 using the shell 100 of the embodiment of the utility model does not need to be provided with a support plate, which can not only reduce the cost of the battery cell 1000, but also reduce the weight of the battery cell 1000, and ensure that the explosion-proof structure 4 can be used normally, thereby improving the safety of the battery cell 1000.

[0040] In some embodiments of the present invention, Figure 1 and Figure 3 As shown, the height of the second protrusion structure 32 protruding toward the installation space 20 is greater than the height of the first protrusion structure 31 protruding toward the installation space 20. In some embodiments, as Figure 3 As shown, the height of the second protrusion structure 32 protruding toward the installation space 20 is L2, and the height of the first protrusion structure 31 protruding toward the installation space 20 is L1, satisfying the relationship L2>L1. In some embodiments, L1=2.4mm, L2=3.2mm. In some embodiments, L1 / L2=20% to 80%.

[0041] By setting the height of the second protrusion structure 32 protruding toward the installation space 20 to be greater than the height of the first protrusion structure 31 protruding toward the installation space 20, when the second protrusion structure 32 supports the electrode group, an exhaust gap is formed between the bottom wall of the electrode group and the first protrusion structure 31, so as to ensure that the explosion-proof structure 4 can be used normally during the thermal runaway of the battery cell 1000, thereby improving the safety of the battery cell 1000.

[0042] In some embodiments of the present invention, Figure 2 and Figure 3 As shown, the groove structure 30 is located between the first protrusion structure 31 and the annular body 22. It can also be understood that a groove structure 30 is formed between the first protrusion structure 31 and the inner circumferential wall of the annular body 22, so that the electrolyte attached to the inner circumferential wall of the annular body 22 can flow into the groove structure 30 along the inner circumferential wall of the annular body 22 under the action of gravity. Moreover, since the groove structure 30 is formed between the first protrusion structure 31 and the inner circumferential wall of the annular body 22, the electrolyte attached to the inner circumferential wall of the annular body 22 can be prevented from being attached to the explosion-proof structure 4, thereby ensuring the reliability of the use of the explosion-proof structure 4.

[0043] In some embodiments of the present invention, Figure 2 and Figure 3 As shown, the groove structure 30 can be constructed as an annular groove, and the groove structure 30 is arranged around the first protrusion structure 31 to form protection in the circumferential direction of the first protrusion structure 31, effectively preventing the electrolyte from adhering to the explosion-proof structure 4 to ensure the reliability of the explosion-proof structure 4.

[0044] In some embodiments of the present invention, Figure 2 and Figure 3 As shown, the end wall of the first protrusion structure 31 opposite to the cover body 1 has a through hole 33 for installing the explosion-proof structure 4. The through hole 33 connects the installation cavity 200 and the external environment of the shell 100 to install the explosion-proof structure 4 in the through hole 33 so that the through hole 33 can be selectively opened or closed.

[0045] In some embodiments, when the pressure inside the installation cavity 200 is within a stable pressure range, the explosion-proof structure 4 closes the through hole 33, that is, the through hole 33 is in a closed state, so that substances in the environment (such as dust, liquid, etc.) can be prevented from entering the installation cavity 200 through the through hole 33, ensuring the stability of the battery cell 1000. In some embodiments, when the pressure inside the installation cavity 200 is greater than the stable pressure range, the explosion-proof structure 4 opens the through hole 33, that is, the through hole 33 is in a conducting state, so that the gas inside the installation cavity 200 can be discharged, ensuring the safety of the battery cell 1000.

[0046] In some embodiments of the present invention, Figure 3As shown, the thickness of the end plate 21 is H1, and the thickness of the annular body 22 is H2, satisfying the relationship: H1≥H2, preferably, H1>H2, so that the end plate 21 and the annular body 22 are designed with non-equal thickness to achieve a lightweight design of the shell 100. In some embodiments, considering that the gas pressure that the end plate 21 needs to withstand is greater than the gas pressure that the annular body 22 needs to withstand, the end plate 21 and the annular body 22 are designed with non-equal thickness, which can not only meet the structural strength requirements of the end plate 21 and the annular body 22, but also achieve a lightweight design of the shell 100.

[0047] In some embodiments, the explosion-proof structure 4 can be constructed as an explosion-proof valve or a waterproof breathable membrane. Preferably, the explosion-proof structure 4 is constructed as an explosion-proof valve. When the pressure inside the installation cavity 200 is greater than the stable pressure range, the explosion-proof structure 4 opens to make the through hole 33 in a conductive state. When the pressure inside the installation cavity 200 is within the stable pressure range, the explosion-proof structure 4 closes to make the through hole 33 in a closed state, thereby ensuring the safety of the battery cell 1000.

[0048] The battery cell 1000 according to the embodiment of the utility model includes a shell 100, a pole group and an explosion-proof structure 4. The shell 100 is the shell 100 of the above embodiment. The shell 100 defines an installation cavity 200, the pole group is installed in the installation cavity 200, and the explosion-proof structure 4 is installed on the shell 100.

[0049] In some embodiments, the shell 100 includes a cover body 1 and a shell body 2. When the cover body 1 is connected to the shell body 2, the cover body 1 and the end plate 21 are arranged relative to each other along a first direction. The cover body 1 closes the open end of the installation space 20 so that the cover body 1 and the shell 100 jointly define an installation cavity 200, and the pole group of the battery cell 1000 is installed in the installation cavity 200.

[0050] In some embodiments, the cover 1 may be formed with an assembly hole, and the pole of the battery cell 1000 is suitable for passing through the assembly hole, so that a part of the structure of the pole is suitable for extending into the installation cavity 200 to connect with the pole group. In some embodiments, the battery cell 1000 may also have a sealing ring, which is suitable for sleeved on the pole, and the sealing ring is suitable for abutting against the inner peripheral wall of the assembly hole, so that the sealing ring is sealed between the inner peripheral wall of the assembly hole and the pole, ensuring the sealing between the pole and the assembly hole.

[0051] In some embodiments, the battery cell 1000 may also have an upper plastic, a lower plastic and a rivet block, the upper plastic is installed on the upper surface of the cover body 1, the lower plastic is installed on the lower surface of the cover body 1, and the rivet block is installed on the upper plastic, and the pole is suitable for passing through the rivet block, and the rivet block is connected to the pole.

[0052] In some embodiments, the cover body 1 is further formed with a liquid injection hole, and the electrolyte can be injected into the mounting cavity 200 through the liquid injection hole.

[0053] The battery pack according to the embodiment of the present invention includes a box body and at least one battery cell 1000 . An assembly space is defined in the box body. The battery cell 1000 is the battery cell 1000 of the above embodiment. The battery cell 1000 is installed in the assembly space.

[0054] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0055] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A battery cell housing, It is characterized in that include: A cover body and a shell body, the shell body includes an end plate and an annular body, the annular body is arranged around the edge of the end plate so that the end plate and the annular body define an installation space with one end open, the cover body is connected to the shell body to close the open end of the installation space, the end plate is formed with a groove structure, and the end plate is also formed with a first protrusion structure protruding toward the installation space, the first protrusion structure and the end wall opposite to the cover body are used for installing an explosion-proof structure.

2. The battery cell housing according to claim 1, It is characterized in that The groove structure is disposed adjacent to the first protrusion structure.

3. The battery cell housing according to claim 1, It is characterized in that The end plate is also formed with a second protruding structure protruding toward the installation space, the second protruding structure is used to support the pole group of the battery cell, the second protruding structure is spaced apart from the first protruding structure, and the groove structure is formed between the second protruding structure and the first protruding structure.

4. The battery cell housing according to claim 3, It is characterized in that A height of the second protrusion structure protruding into the installation space is greater than a height of the first protrusion structure protruding into the installation space.

5. The battery cell housing according to claim 1, It is characterized in that The groove structure is located between the first protrusion structure and the annular body.

6. The battery cell housing according to claim 1, It is characterized in that The groove structure is annular and is arranged around the first protrusion structure.

7. The battery cell housing according to claim 1, It is characterized in that The end wall of the first protrusion structure opposite to the cover body has a through hole for installing the explosion-proof structure.

8. The battery cell housing according to claim 1, It is characterized in that The thickness of the end plate is H1, and the thickness of the annular body is H2, satisfying the relationship: H1≥H2.

9. A battery cell, It is characterized in that include: A housing, wherein the housing is a housing according to any one of claims 1 to 8, and a mounting cavity is defined in the housing; A pole group, the pole group is installed in the installation cavity; An explosion-proof structure is installed on the shell.

10. A battery pack, It is characterized in that include: A box body, wherein an assembly space is defined within the box body; At least one battery cell, wherein the battery cell is the battery cell according to claim 9, and the battery cell is installed in the assembly space.

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