Battery cell shell, battery cell and power utilization device

Abstract

The embodiment of the invention provides a battery cell shell, a battery cell and a power utilization device. The battery cell shell comprises a shell, the shell comprises a first shell and a second shell, the first shell and the second shell are in butt joint to define a cavity, and a liquid injection hole is formed in the first shell and / or the second shell; the first shell and the second shell are bonded and fixed through a sealing glue layer, the sealing glue layer covers the connecting position between the first shell and the second shell in a sealing mode, and the sealing glue layer covers the liquid injection hole in a sealing mode. According to the battery cell shell, the battery cell, the battery module and the power utilization device provided by the embodiment of the invention, reliable sealing can be realized while the cost of a sealing process is reduced, and the safety of the battery cell is improved.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and in particular relates to a battery cell housing, a battery cell and an electrical device. Background Art

[0002] The cell shell of the existing hard shell battery cell includes many parts, and the parts are connected and sealed by welding. After the cell shell is processed, it is necessary to reserve a liquid injection hole on it to complete the liquid injection in the subsequent processing steps of the battery cell. After the liquid injection of the battery cell is completed, it is necessary to weld and fix the sealing nail in the liquid injection hole to seal the liquid injection hole.

[0003] However, the welding process is difficult and costly, which leads to high difficulty and cost in the overall processing of the battery cell shell. In addition, there is a high risk of leakage from the welding seal, which affects the safety of the battery cell. Summary of the invention

[0004] The embodiments of the present application provide a battery cell housing, a battery cell, and an electrical device, which can achieve reliable sealing of the overall structure while reducing the cost of the sealing process, thereby improving the safety of the battery cell.

[0005] In a first aspect, an embodiment of the present application provides a battery cell shell, wherein the battery cell shell includes a shell and a sealing layer, the shell includes a first shell and a second shell, which are joined and enclosed to form a cavity, and an injection hole is provided on the first shell and / or the second shell; the sealing layer bonds and fixes the first shell and the second shell, the sealing layer seals and covers the connection between the first shell and the second shell, and the sealing layer seals and covers the injection hole.

[0006] In some embodiments, the sealant layer includes a first portion and a second portion connected to each other; the first portion is bonded to the outer surface of the first shell and the outer surface of the second shell and covers the injection hole;

[0007] The second part extends from one side of the first part around the outer surface of the first shell and the outer surface of the second shell to the other side of the first part and is fixedly connected to the first part, and the second part is bonded and fixed to the outer surface of the first shell and the outer surface of the second shell.

[0008] In some embodiments, the sealant layer also includes a third part, the second part is connected between the first part and the third part, the third part covers and is bonded to the side of the first part facing away from the shell, and along the thickness direction of the third part, the projection of the third part covers the injection hole.

[0009] In some embodiments, the first portion is provided with a connecting hole, the connecting hole is connected to the injection hole, and the third portion covers and seals the connecting hole.

[0010] In some embodiments, the communication hole is concentric with the injection hole.

[0011] In some embodiments, the first portion is fused fixedly connected to the third portion.

[0012] In some embodiments, the first shell has a first shell bottom and a first shell wall, the first shell wall is connected to the first shell bottom, and the first shell bottom and the first shell wall are combined to form a first recess;

[0013] The second shell has a second shell bottom and a second shell wall, the second shell wall is connected to the second shell bottom, and the second shell bottom and the second shell wall are combined to form a second recess;

[0014] The first shell wall is sealedly connected to the second shell wall, and the first recess and the second recess are combined to form a cavity;

[0015] The sealant layer seals and covers the connection between the first shell wall and the second shell wall.

[0016] In some embodiments, the injection hole is opened in the first shell, or the injection hole is opened in the second shell, or the injection hole is defined by the first shell and the second shell.

[0017] In some embodiments, a first notch is formed at an edge of the first shell wall away from the first shell bottom, and the first notch and an edge of the second shell wall away from the second shell bottom are combined to form a liquid injection hole;

[0018] Or, a second notch is formed at an edge of the second shell wall away from the second shell bottom, and the second notch and the edge of the first shell wall away from the first shell bottom are combined to form a liquid injection hole;

[0019] Alternatively, a first notch is formed at an edge of the first shell wall away from the first shell bottom, and a second notch is formed at an edge of the second shell wall away from the second shell bottom, and the first notch and the second notch are combined to form a liquid injection hole.

[0020] In some embodiments, a portion of the sealant layer is sealed and filled in the gap between the first shell wall and the second shell wall.

[0021] In some embodiments, along the thickness direction of the first part, the projection of the injection hole falls into the projection of the first part, the edge of the first part exceeds the hole edge of the injection hole, and there is a preset distance between the edge of the first part and the hole edge of the injection hole, and the preset distance is greater than or equal to 0.03 mm.

[0022] In some embodiments, the first shell is used to lead out a first polarity of the battery cell, the second shell is used to lead out a second polarity of the battery cell, and the first shell and the second shell are insulated.

[0023] In a second aspect, an embodiment of the present application provides a battery cell, wherein the battery cell comprises an electrode assembly and a battery cell shell as described in the first aspect, and the electrode assembly is disposed in a cavity of the battery cell shell.

[0024] In a third aspect, an embodiment of the present application provides an electrical device, wherein the electrical device includes the battery cell as described in the second aspect, and the battery cell is used to provide electrical energy.

[0025] The battery cell shell, battery cell and electrical device of the embodiments of the present application are formed by docking a first shell and a second shell, and a sealing layer is used to connect and seal the docking position between the first shell and the second shell. At the same time, the injection hole is sealed by the sealing layer, so that a battery cell shell with a sealed space can be formed, and the difficulty and cost of sealing the battery cell shell can be effectively reduced, the risk of leakage is reduced, and the safety of the battery cell is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0027] Figure 1 A schematic diagram of the structure of a battery housing provided in some embodiments of the present application;

[0028] Figure 2 A schematic diagram of a partial structure of a battery housing provided in some embodiments of the present application;

[0029] Figure 3 Another schematic diagram of the structure of a battery housing provided in some embodiments of the present application;

[0030] Figure 4 A partial cross-sectional view of a battery housing provided for some embodiments of the present application;

[0031] Figure 5 Another partial cross-sectional view of a battery housing provided for some embodiments of the present application;

[0032] Figure 6 Another partial cross-sectional view of a battery casing provided for some embodiments of the present application.

[0033] Description of Figure Numbers:

[0034] 1. Shell; 11. First shell; 111. First shell bottom; 112. First shell wall; 113. First notch; 12. Second shell; 121. Second shell bottom; 122. Second shell wall; 123. Second notch; 13. Liquid injection hole;

[0035] 2. Sealant layer; 21. First part; 211. Communication hole; 22. Second part; 23. Third part;

[0036] S. Preset distance. DETAILED DESCRIPTION

[0037] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0038] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0039] The battery cell housing, battery cell and electrical device of the present application are described below with reference to the accompanying drawings.

[0040] like Figure 1 and Figure 2 As shown, in a first aspect, an embodiment of the present application provides a battery cell shell, wherein the battery cell shell includes a shell 1 and a sealant layer 2 .

[0041] The shell 1 has a sealed space inside for accommodating the electrode assembly. The shell 1 has a liquid injection hole 13, through which electrolyte is injected into the shell 1 to form a battery core.

[0042] The housing 1 includes a first shell 11 and a second shell 12 . The first shell 11 and the second shell 12 are connected to form a cavity. The injection hole 13 is opened in the first shell 11 and / or the second shell 12 .

[0043] The sealant layer 2 bonds and fixes the first shell 11 and the second shell 12, and realizes the sealing of the joint between the first shell 11 and the second shell 12. Specifically, the sealant layer 2 is bonded to the outer surface of the first shell 11 and the outer surface of the second shell 12 and seals and covers the injection hole 13, so that the injection hole 13 is closed after the electrolyte injection is completed, thereby completing the sealing of the shell 1.

[0044] like Figures 1 to 3As shown, in some embodiments, the sealant layer 2 includes a first portion 21 and a second portion 22 .

[0045] The first portion 21 is bonded to the outer surface of the first shell 11 and the outer surface of the second shell 12 and covers the injection hole 13 , forming a first layer of sealing on the outer side of the injection hole 13 .

[0046] The second portion 22 extends from one side of the first portion 21 around the outer surface of the first shell 11 and the outer surface of the second shell 12 to the other side of the first portion 21, and is fixedly connected to the first portion 21 to form an annular structure wrapped around the surface of the shell 1, and the second portion 22 is bonded and fixed to the outer surface of the first shell 11 and the outer surface of the second shell 12. After the sealant layer 2 and the shell 1 are bonded and fixed, it can firmly wrap around the surface of the shell 1, further improving the connection reliability between the sealant layer 2 and the shell 1.

[0047] like Figure 2 As shown, in some embodiments, the sealant layer 2 further includes a third part 23, and the second part 22 is connected between the first part 21 and the third part 23. The third part 23 covers and is bonded to the side of the first part 21 away from the housing 1, and along the thickness direction of the third part 23, the projection of the third part 23 covers the injection hole 13. The structural strength of the annular structure formed by the sealant layer 2 is further strengthened; at the same time, the first part 21 can be positioned by the third part 23, reducing the risk of displacement of the first part 21 relative to the housing 1, and ensuring that the first part 21 effectively covers and seals the injection hole 13; and the first part 21 can be further protected and strengthened by the third part 23, reducing the risk of damage to the first part 21 by force.

[0048] The first part 21, the second part 22 and the third part 23 are integrally formed and connected, and the second part 22 is arranged between the first part 21 and the third part 23, that is, the sealant layer 2 is an integral sealant layer 2 to ensure the connection reliability between the parts. The second part 22 is arranged between the first part 21 and the third part 23 here refers to the positional relationship of the sealant layer 2 in the unfolded state.

[0049] like Figures 3 to 5 As shown, in some embodiments, the first part 21 is provided with a connecting hole 211, the connecting hole 211 is connected to the injection hole 13, and the third part 23 covers and seals the connecting hole 211. During the process of assembling the battery cell, after the first shell 11 and the second shell 12 are bonded and fixed by the first part 21 and the second part 22, the connecting port of the first part 21 is connected to the injection hole 13, so that the injection hole 13 can be kept open while the shell 1 is sealed. At this time, liquid can be injected into the shell 1 through the injection hole 13. After the injection is completed, the third part 23 covers the first part 21, so as to achieve the closure of the injection hole 13 and the connecting port.

[0050] In some embodiments, the connecting hole 211 is concentric with the injection hole 13, which can maximize the flow area of ​​the connecting hole 211 and the injection hole 13 and ensure smooth injection of the electrolyte.

[0051] The actual flow area of ​​the injection hole 13 is the overlapping area of ​​the projections of the injection hole 13 and the connecting hole 211 along the through direction.

[0052] Alternatively, if Figure 4 As shown, the diameter of the injection hole 13 is smaller than the diameter of the connecting hole 211 . When the injection hole 13 is concentric with the connecting hole 211 , the flow area of ​​the injection hole 13 is the actual connecting area of ​​the injection hole 13 .

[0053] Alternatively, if Figure 4 As shown, an insertion port may be extended and formed on the outer surface of the housing 1 , the insertion port is communicated with the liquid injection hole 13 , and the insertion port is inserted into the interior of the communication hole 211 .

[0054] Alternatively, if Figure 5 As shown, the diameter of the injection hole 13 is larger than the diameter of the connecting hole 211 . When the injection hole 13 is concentric with the connecting hole 211 , the flow area of ​​the injection hole 13 is the actual connecting area of ​​the connecting hole 211 .

[0055] It should be noted that when the tolerance between the center of the injection hole 13 and the center of the communicating hole 211 is less than or equal to 0.03 mm, the injection hole 13 and the communicating hole 211 can be considered to be concentric.

[0056] Optionally, in some embodiments, the first part 21 is fixedly connected by melting with the third part 23. Specifically, after the sealing adhesive layer 2 is bonded to the housing 1 and the third part 23 covers the first part 21, the side of the third part 23 facing away from the first part 21 is heated to melt the third part 23, and after the third part 23 is solidified, it can effectively become one with the first part 21, thereby effectively improving the reliability of the combination of the third part 23 and the first part 21.

[0057] like Figure 3 As shown, in some embodiments, the first shell 11 has a first shell bottom 111 and a first shell wall 112, the first shell wall 112 is connected to the first shell bottom 111, and the first shell bottom 111 and the first shell wall 112 are integrally formed to ensure the structural strength and sealing of the first shell 11. The first shell bottom 111 and the first shell wall 112 are enclosed to form a first recessed portion, and the first recessed portion faces the second shell 12.

[0058] The second shell 12 has a second shell bottom 121 and a second shell wall 122. The second shell wall 122 is connected to the second shell bottom 121 in a circumferential manner. The second shell bottom 121 and the second shell wall 122 are integrally formed to ensure the structural strength and sealing of the second shell 12. The second shell bottom 121 and the second shell wall 122 are enclosed to form a second recessed portion, which faces the first shell 11.

[0059] The first shell wall 112 is sealedly connected to the second shell wall 122 , and the first recess is relatively communicated with the second recess to form a cavity of the shell 1 .

[0060] The first shell wall 112 and the second shell wall 122 are connected by a sealant layer 2, and the sealant layer 2 seals and covers the connection between the first shell wall 112 and the second shell wall 122 to form a sealed shell 1 structure. The sealant layer 2 is not only used to realize the connection of the injection hole 13, but also used to realize the connection between the first shell 11 and the second shell 12.

[0061] like Figure 3 As shown, in some embodiments, the injection hole 13 can be only provided in the first shell 11, or the injection hole 13 can be only provided in the second shell 12, or the injection hole 13 is defined by the first shell 11 and the second shell 12. The injection hole 13 provided in any of the above-mentioned ways can be sealed by the sealant layer 2.

[0062] In some embodiments, a first notch 113 is provided at an edge of the first shell wall 112 away from the first shell bottom 111, and the first notch 113 and the edge of the second shell wall 122 away from the second shell bottom 121 are combined to form a liquid injection hole 13, which can effectively reduce the processing difficulty and cost compared to directly opening a hole structure on the shell 1.

[0063] In some embodiments, a second notch 123 is opened at the edge of the second shell wall 122 away from the second shell bottom 121, and the second notch 123 and the edge of the first shell wall 112 away from the first shell bottom 111 are combined to form a liquid injection hole 13. Compared with directly opening a hole structure on the shell 1, it can effectively reduce the processing difficulty and processing cost.

[0064] like Figure 3 As shown, in some embodiments, a first notch 113 is formed at the edge of the first shell wall 112 away from the first shell bottom 111, and a second notch 123 is formed at the edge of the second shell wall 122 away from the second shell bottom 121. The first notch 113 and the second notch 123 are enclosed to form a liquid injection hole 13. This facilitates the formation of a liquid injection hole 13 with a symmetrical structure, and helps to leave enough area around the periphery of the liquid injection hole 13 to achieve bonding with the sealant layer 2.

[0065] Optionally, the first notch 113 is a semicircular notch, the second notch 123 is a semicircular notch, and the radius of the first notch 113 and the second notch 123 are the same. After the first shell 11 and the second shell 12 are assembled, the first notch 113 and the second notch 123 are combined to form a circular injection hole 13. The circular injection hole 13 has the advantage of isotropy, which can effectively improve the sealing reliability of the injection hole 13 and minimize the risk of leakage.

[0066] like Figure 6 As shown, in some embodiments, a portion of the sealant layer 2 is sealed and filled in the gap between the first shell wall 112 and the second shell wall 122 to further increase the bonding area of ​​the sealant layer 2 at the connection between the first shell 11 and the second shell 12, thereby improving the sealing effect of the sealant layer 2 at the connection between the first shell 11 and the second shell 12.

[0067] In some embodiments, along the through direction of the first portion 21 , the projection of the injection hole 13 all falls into the projection of the first portion 21 to ensure that the first portion 21 completely covers and seals the injection hole 13 , thereby reducing the risk of leakage and improving the safety of the battery cell.

[0068] The edge of the first part 21 exceeds the edge of the injection hole 13, that is, the edge of the first part 21 surrounds the outside of the edge of the injection hole 13, and there is a preset distance S between the edge of the first part 21 and the edge of the injection hole 13, so that the sealant layer 2 has a certain effective bonding area with the shell 1 at each position around the injection hole 13, thereby further ensuring the sealing effect of the sealant layer 2 on the injection hole 13.

[0069] The preset distance S is greater than or equal to 0.03 mm, so that the bonding width between the edge of the sealant layer 2 and the edge of the injection hole 13 is greater than or equal to 0.03 mm, ensuring the bonding area of ​​the sealant layer 2 between the periphery of the injection hole 13 and the shell 1, and ensuring the long-term sealing effect of the sealant layer 2 on the injection hole 13.

[0070] In some embodiments, the first shell 11 is used to lead out the first polarity of the battery cell, and the second shell 12 is used to lead out the second polarity of the battery cell. The first shell 11 and the second shell 12 are insulated, and the first shell 11 is electrically connected to the positive electrode sheet inside the shell 1, and the second shell 12 is electrically connected to the negative electrode sheet inside the shell 1 to achieve circuit conduction of the battery cell. By directly leading out the two polarities through the two shells, there is no need to set up a pole assembly, making the structure more convenient and low-cost.

[0071] The two shells are used to lead out the two polarities of the battery cell. The outermost layer of one of the pole pieces can be single-sided coated, and the outer single-sided area directly contacts the first shell 11, or directly contacts the first shell through the pole ear, or is bonded by conductive glue. The other pole piece can also be designed similarly.

[0072] In a second aspect, an embodiment of the present application provides a battery cell, wherein the battery cell comprises an electrode assembly and a battery cell shell as described in the first aspect, wherein the electrode assembly is disposed in a cavity of the battery cell shell and the electrode assembly is connected to a first shell 11 and a second shell 12 respectively.

[0073] The battery cell provided in the embodiment of the present application has a shell 1 formed by docking a first shell 11 and a second shell 12, and a sealant layer 2 is used to connect and seal the docking position between the first shell 11 and the second shell 12. At the same time, the injection hole 13 is sealed by the sealant layer 2, so that a battery cell shell 1 with a sealed space can be formed, and the difficulty and cost of sealing the battery cell shell 1 are effectively reduced, the risk of leakage is reduced, and the safety of the battery cell is improved.

[0074] In the electrical device of the embodiment of the present application, the shell 1 of the battery cell is formed by docking the first shell 11 and the second shell 12, and the sealing layer 2 is used to connect and seal the docking position between the first shell 11 and the second shell 12. At the same time, the injection hole 13 is sealed by the sealing layer 2, so that the battery cell shell 1 with a sealed space can be formed, and the difficulty and cost of sealing the battery cell shell 1 are effectively reduced, the risk of leakage is reduced, and the safety of the battery cell is improved.

[0075] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A battery cell casing, characterized in that: The battery cell housing comprises: The shell comprises a first shell and a second shell, which are connected and enclosed to form a cavity, and a liquid injection hole is provided on the first shell and / or the second shell; A sealant layer is used to bond and fix the first shell and the second shell. The sealant layer seals and covers the connection between the first shell and the second shell, and the sealant layer seals and covers the injection hole.

2. The battery cell casing according to claim 1, characterized in that: The sealant layer includes a first portion and a second portion connected to each other; The first part is bonded to the outer surface of the first shell and the outer surface of the second shell and covers the injection hole; The second part extends from one side of the first part around the outer surface of the first shell and the outer surface of the second shell to the other side of the first part and is fixedly connected to the first part, and the second part is bonded and fixed to the outer surface of the first shell and the outer surface of the second shell.

3. The battery cell casing according to claim 2, characterized in that: The sealant layer also includes a third part, the second part is connected between the first part and the third part, the third part covers and is bonded to a side of the first part away from the shell, and along the thickness direction of the third part, the projection of the third part covers the injection hole.

4. The battery cell casing according to claim 3, characterized in that: The first part is provided with a communication hole, the communication hole is communicated with the injection hole, and the third part covers and seals the communication hole.

5. The battery cell casing according to claim 4, characterized in that: The communicating hole is concentric with the liquid injection hole.

6. The battery cell casing according to any one of claims 3 to 5, characterized in that: The first portion is fixedly connected to the third portion by melting.

7. The battery cell casing according to claim 1, characterized in that: The first shell has a first shell bottom and a first shell wall, the first shell wall is connected to the first shell bottom, and the first shell bottom and the first shell wall are combined to form a first recess; The second shell has a second shell bottom and a second shell wall, the second shell wall is connected to the second shell bottom, and the second shell bottom and the second shell wall are combined to form a second recess; The first shell wall is sealed to the second shell wall, and the first recess and the second recess are combined to form the cavity; The sealant layer seals and covers the connection between the first shell wall and the second shell wall.

8. The battery cell casing according to claim 7, characterized in that: The injection hole is opened in the first shell, or the injection hole is opened in the second shell, or the injection hole is defined by the first shell and the second shell.

9. The battery cell casing according to claim 7, characterized in that: A first notch is formed at an edge of the first shell wall away from the first shell bottom, and the first notch and the edge of the second shell wall away from the second shell bottom together form the injection hole; Or, a second notch is formed at an edge of the second shell wall away from the second shell bottom, and the second notch and the edge of the first shell wall away from the first shell bottom together form the injection hole; Alternatively, a first notch is formed at an edge of the first shell wall away from the first shell bottom, and a second notch is formed at an edge of the second shell wall away from the second shell bottom, and the first notch and the second notch are combined to form the injection hole.

10. The battery cell casing according to claim 7, characterized in that: A portion of the sealant layer is sealed and filled in the gap between the first shell wall and the second shell wall.

11. The battery cell casing according to claim 2, characterized in that: Along the thickness direction of the first part, the projection of the injection hole falls into the projection of the first part, the edge of the first part exceeds the hole edge of the injection hole, and there is a preset distance between the edge of the first part and the hole edge of the injection hole, and the preset distance is greater than or equal to 0.03mm.

12. The battery cell casing according to claim 1, characterized in that: The first shell is used to lead out the first polarity of the battery cell, and the second shell is used to lead out the second polarity of the battery cell. The first shell and the second shell are insulated.

13. A battery cell, characterized in that: The battery cell comprises an electrode assembly and a battery cell shell as claimed in any one of claims 1 to 12, wherein the electrode assembly is disposed in a cavity of the battery cell shell.

14. An electrical device, characterized in that: The electrical device comprises the battery cell as claimed in claim 13, and the battery cell is used to provide electrical energy.

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