Shell structure and battery monomer with same

Abstract

The utility model discloses a shell structure and a battery monomer with the same. The shell structure comprises a first shell, a second shell and a third shell, the second shell is arranged in the first shell, the second shell is an insulating corrosion-resistant piece, a containing cavity is defined in the second shell, and the containing cavity is used for containing electrolyte and an electrode assembly. According to the shell structure disclosed by the utility model, the second shell of the insulating corrosion-resistant piece is arranged, so that the electrolyte can be prevented from being in contact with the first shell to corrode the first shell, and the reliability and the safety of the single battery are improved.

Description

Technical Field

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

[0002] In the related art, the outer shell of the battery cell is made of aluminum material, and the aluminum shell is in direct contact with the electrolyte. When the relative potential between the aluminum shell and the electrodes of the battery cell is abnormal, the electrolyte will react with the aluminum shell to corrode the aluminum shell, thereby affecting the reliability and 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, the utility model proposes a shell structure, which can improve the reliability and safety of the battery cell during operation.

[0004] The utility model also provides a battery monomer having the shell structure.

[0005] According to the shell structure of the first aspect of the utility model, the shell structure is used for a battery cell, and the shell structure includes: a first shell; a second shell, the second shell is arranged in the first shell, the second shell is an insulating corrosion-resistant part, and a accommodating cavity is defined in the second shell, and the accommodating cavity is used to accommodate an electrolyte and an electrode assembly.

[0006] According to the shell structure of the first aspect of the utility model, by providing the second shell of the insulating corrosion-resistant member, it is possible to avoid corrosion of the first shell caused by contact between the electrolyte and the first shell, thereby improving the reliability and safety of the battery cell.

[0007] According to some embodiments of the present invention, the second shell is a plastic part.

[0008] According to some embodiments of the utility model, at least one end in the first direction is defined in the first shell to be open, and at least one end of the accommodating cavity in the first direction is open and formed as an opening, and the shell structure also includes: a cover plate assembly, which is covered on the open sides of the first shell and the second shell, and the cover plate assembly includes a cover plate and an insulating member, the cover plate is sealed and connected to the first shell to cover the open end of the first shell, and the insulating member is sealed and connected to the second shell to cover the opening.

[0009] According to some embodiments of the present invention, the cover plate is connected to the first shell by welding; and / or the insulating member is connected to the second shell by hot melting.

[0010] According to some embodiments of the utility model, there are two cover plate assemblies, namely a first cover plate assembly and a second cover plate assembly, the first cover plate assembly and the second cover plate assembly are respectively arranged at the two ends of the first shell and the second shell in the first direction, an explosion-proof hole is formed on the cover plate of the first cover plate assembly and penetrates the cover plate along the thickness direction, an explosion-proof valve is provided at the explosion-proof hole, an exhaust hole is formed on the insulating part of the first cover plate assembly and penetrates the insulating part along the thickness direction, the exhaust hole is opposite to the explosion-proof hole, and the first cover plate assembly also includes: a sealing film, the sealing film covers the exhaust hole, and the sealing film is configured to open the exhaust hole when thermal runaway occurs in the battery cell.

[0011] According to some embodiments of the utility model, a liquid injection hole is formed on the second cover plate assembly and penetrates the second cover plate assembly along the thickness direction, and the liquid injection hole is connected to the accommodating cavity. The second cover plate assembly also includes a sealing nail, and the sealing nail seals the liquid injection hole.

[0012] According to some embodiments of the present invention, the shell structure further includes: a support member, wherein the support member is supported between the first shell and the second shell.

[0013] According to some embodiments of the present invention, in the thickness direction of the first shell, the distance between the first shell and the second shell is 1 mm-5 mm.

[0014] According to some embodiments of the present invention, the support member includes a plurality of protrusions, both ends of the protrusions are fixed to the first shell, and the middle portion of the protrusions protrudes toward the second shell and abuts against the second shell through the arc surface of the protrusions.

[0015] A battery cell according to a second aspect of the present invention comprises: the housing structure according to the first aspect of the present invention.

[0016] According to the battery cell of the second aspect of the present invention, by providing the housing structure according to the first aspect of the present invention, the reliability and safety of the battery cell can be improved.

[0017] 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

[0018] Figure 1 is a cross-sectional view of a housing structure according to an embodiment of the utility model;

[0019] Figure 2 yes Figure 1 A schematic diagram of the support member and the first shell shown in ;

[0020] Figure 3 yes Figure 1 Schematic diagram of the first cover plate assembly shown in .

[0021] Reference numerals:

[0022] 100. Shell structure;

[0023] 10. First shell;

[0024] 20. second shell; 21. accommodating chamber;

[0025] 30, cover plate assembly; 30a, first cover plate assembly; 30b, second cover plate assembly; 31, cover plate; 311, explosion-proof valve; 32, insulating member; 321, exhaust hole; 322, sealing film;

[0026] 40. Support members. DETAILED DESCRIPTION

[0027] 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 intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0028] Reference below Figure 1-Figure 3 A housing structure 100 according to an embodiment of the first aspect of the present invention is described.

[0029] like Figure 1 As shown, according to the housing structure 100 of the first embodiment of the present invention, the housing structure 100 is used for a battery cell and includes: a first shell 10 and a second shell 20 .

[0030] Specifically, the second shell 20 is disposed in the first shell 10 . The second shell 20 is an insulating corrosion-resistant part. A receiving cavity 21 is defined in the second shell 20 . The receiving cavity 21 is used to receive the electrolyte and the electrode assembly.

[0031] The first shell 10 is made of aluminum material, and the electrolyte and the battery assembly can realize the charging and discharging functions of the battery cell.

[0032] When the battery cell is assembled, the second shell 20 can isolate the electrolyte from the first shell 10, thereby preventing the electrolyte from contacting the first shell 10 and corroding the first shell 10, thereby improving the reliability and safety of the battery cell. At the same time, setting the second shell 20 as an insulating and corrosion-resistant part can reduce the degree of corrosion of the second shell 20 by the electrolyte, thereby further improving the reliability and safety of the battery cell.

[0033] It is understandable to those skilled in the art that after the battery cells are assembled on the battery, multiple battery cells will be stacked. The battery cells will generate heat during operation, and the heat generated by the electrode assembly and the electrolyte is relatively large. By providing the first shell 10 and the second shell 20, the spacing between the second shells 20 on different battery cells can be increased, thereby improving the heat dissipation effect.

[0034] According to the housing structure 100 of the first embodiment of the utility model, by providing the second housing 20 of the insulating corrosion-resistant part, it is possible to avoid corrosion of the first housing 10 caused by contact between the electrolyte and the first housing 10, thereby improving the reliability and safety of the battery cell.

[0035] In some embodiments of the present invention, the second shell 20 is a plastic part. Plastic parts are insulating and corrosion-resistant. By setting the second shell 20 as a plastic part, the use requirements of the second shell 20 can be met. Preferably, the second shell 20 is a polypropylene plastic part or a polyphenylene sulfide plastic part.

[0036] In some embodiments of the present invention, Figure 1 As shown, at least one end in the first direction is open in the first shell 10, and the accommodating cavity 21 is open at least one end in the first direction and formed as an opening. The shell structure 100 also includes: a cover assembly 30, which is arranged on the open sides of the first shell 10 and the second shell 20. The cover assembly 30 includes a cover 31 and an insulating member 32. The cover 31 is sealed and connected to the first shell 10 to cover the open end of the first shell 10, and the insulating member 32 is sealed and connected to the second shell 20 to cover the opening.

[0037] In this way, the electrolyte in the accommodating cavity 21 can be isolated from the first shell 10, wherein the open end of the first shell 10 can provide an assembly channel for the second shell 20, and the opening of the accommodating cavity 21 can provide an assembly channel for the electrode assembly, thereby realizing the assembly of the battery cell and reducing the difficulty of assembly.

[0038] In some embodiments of the present invention, the cover plate 31 is welded to the first shell 10. The welded connection can achieve a sealed connection between the cover plate 31 and the first shell 10, and the welded connection has high reliability, thereby enabling the connection between the cover plate 31 and the first shell 10 to meet the use requirements of the battery cell. In addition, the welded connection can improve production efficiency. Preferably, the cover plate 31 is laser welded to the first shell 10, which can further improve production efficiency.

[0039] In some embodiments of the present invention, the insulating member 32 is connected to the second shell 20 by heat melting. Thus, a sealed connection between the insulating member 32 and the second shell 20 can be achieved, and the material properties of the connection point do not change after the insulating member 32 and the second shell 20 are connected. In the process of product design, it is not necessary to consider whether the material properties of the connection point meet the use requirements, which can reduce the difficulty of product design.

[0040] In some embodiments of the present invention, Figure 1 and Figure 3 As shown, there are two cover plate assemblies 30, namely a first cover plate assembly 30a and a second cover plate assembly 30b. The first cover plate assembly 30a and the second cover plate assembly 30b are respectively arranged at the two ends of the first shell 10 and the second shell 20 in the first direction, that is, the first shell 10 is open at both ends in the first direction, and the accommodating cavity 21 is formed with openings at both ends in the first direction.

[0041] An explosion-proof hole is formed on the cover plate 31 of the first cover plate assembly 30a and penetrates the cover plate 31 along the thickness direction. An explosion-proof valve 311 is provided at the explosion-proof hole. An exhaust hole 321 is formed on the insulating member 32 of the first cover plate assembly 30a and penetrates the insulating member 32 along the thickness direction. The exhaust hole 321 is opposite to the explosion-proof hole. The first cover plate assembly 30a also includes: a sealing film 322, which covers the exhaust hole 321. The sealing film 322 is configured to open the exhaust hole 321 when thermal runaway occurs in the battery cell.

[0042] The sealing film 322 may melt to open the exhaust hole 321 when the temperature is greater than a set threshold, or may break to open the exhaust hole 321 when the pressure in the accommodating cavity 21 is greater than a set threshold.

[0043] When a battery cell experiences thermal runaway, the high-temperature and high-pressure gas and high-temperature and high-pressure substances in the battery cell can be discharged from the accommodating cavity 21 through the exhaust hole 321. At the same time, the explosion-proof valve 311 opens the explosion-proof hole, and the high-temperature and high-pressure gas and high-temperature and high-pressure substances are discharged from the battery cell through the explosion-proof hole. This can reduce the probability of thermal runaway of the battery cell, thereby improving safety.

[0044] Preferably, the sealing film 322 may be a polypropylene film or a polyethylene terephthalate film.

[0045] In some embodiments of the utility model, a liquid injection hole (not shown in the drawings) is formed on the second cover plate assembly 30b and penetrates the second cover plate assembly 30b along the thickness direction. The liquid injection hole is connected to the accommodating cavity 21. The second cover plate assembly 30b also includes a sealing nail, which seals the liquid injection hole.

[0046] During the production process, the electrode assembly is first assembled into the accommodating cavity 21 from the opening, and then the second shell 20 is assembled into the first shell 10 from the open end of the first shell 10, and then the first cover plate assembly 30a and the second cover plate assembly 30b are sealed on both ends of the first shell 10 and the second shell 20, and the insulating member 32 is sealedly connected to the first shell 10, and the cover plate 31 is sealedly connected to the second shell 20, and then liquid is injected into the accommodating cavity 21 through the injection hole. After the injection is completed, the injection hole is sealed with a sealing nail, thereby completing the assembly of the battery cell.

[0047] Among them, the operation of sealing the injection hole with a sealing nail is relatively simple, which can reduce the production difficulty and improve the production efficiency.

[0048] In some embodiments of the utility model, poles are provided on the first cover plate assembly 30a and the second cover plate assembly 30b, one is a positive pole and the other is a negative pole, the insulating member 32 is provided with a first pole hole, the cover plate 31 is provided with a second pole hole, and the poles pass through the first pole hole and the second pole hole and are riveted to the cover plate 31. In this way, the charging and discharging functions of the battery cell can be realized, and the connection between the insulating member 32 and the cover plate 31 can be realized.

[0049] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, the shell structure 100 further includes: a support member 40, which is supported between the first shell 10 and the second shell 20. In this way, the heat dissipation area of ​​the second shell 20 can be increased, thereby further improving the heat dissipation effect of the battery cell, and when the battery cell has thermal runaway and the second shell 20 melts, the support member 40 can provide support for the electrode assembly, so that the circumference of the electrode assembly has an exhaust space, further improving the reliability and safety of the battery cell.

[0050] In some embodiments of the present invention, the spacing between the first shell 10 and the second shell 20 is 1 mm to 5 mm in the thickness direction of the first shell 10. For example, the spacing between the first shell 10 and the second shell 20 may be 1 mm, 2.4 mm, 3 mm or 5 mm, thereby enabling the spacing between the first shell 10 and the second shell 20 to meet the use requirements of the battery cell, and the spacing between the first shell 10 and the second shell 20 may be adjusted during product design to meet more product design requirements.

[0051] In some embodiments of the present invention, Figure 1 and Figure 2As shown, the support member 40 includes a plurality of convex parts, the two ends of the convex parts are fixed to the first shell 10, and the middle part of the convex part is convex toward the second shell 20 and abuts against the second shell 20 through the convex curved surface. In this way, the surface area of ​​the support member 40 can be increased, and a plurality of gaps will be generated between the plurality of convex parts, so that when heat is transferred from the second shell 20 to the support member 40, the heat exchange efficiency between the support member 40 and the first shell 10 is high, thereby further improving the heat dissipation effect of the battery cell. Among them, the convex part abuts against the second shell 20 through the curved surface, which can reduce the probability of the convex part causing damage to the second shell 20 during the assembly and use of the battery cell, thereby improving the yield rate of the battery cell, and further improving the reliability and safety of the battery cell.

[0052] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, the two ends of the plurality of convex parts are connected in sequence, and the connection between the two convex parts is connected to the first shell 10 through the raised arc surface. In this way, the coverage of the convex part on the support member 40 can be increased, thereby further increasing the surface area of ​​the support member 40 and improving the heat dissipation effect of the battery cell. In addition, the contact area between the convex part and the first shell 10 can be increased, thereby reducing the difficulty of connecting the convex part with the first shell 10 and reducing the difficulty of production.

[0053] In some embodiments of the present invention, the protrusion is welded to the first shell 10. The welding connection is convenient to operate, and has high connection strength and reliability, thereby improving production efficiency and ensuring that the connection strength and reliability between the protrusion and the first shell 10 meet the use requirements.

[0054] The battery cell according to the embodiment of the second aspect of the utility model comprises: the shell structure 100 according to the embodiment of the first aspect of the utility model.

[0055] According to the battery cell of the second embodiment of the utility model, the reliability and safety of the battery cell can be improved by providing the housing structure 100 according to the first embodiment of the utility model.

[0056] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0057] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0058] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like 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, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0059] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. 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 representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0060] 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 housing structure, the housing structure being used for a battery cell, characterized in that: include: first shell; The second shell is arranged in the first shell, the second shell is an insulating corrosion-resistant part, and a containing cavity is defined in the second shell, and the containing cavity is used to contain electrolyte and electrode assembly.

2. The housing structure according to claim 1, characterized in that: The second shell is a plastic part.

3. The housing structure according to claim 2, characterized in that: The first shell defines at least one end in the first direction that is open, and the accommodating cavity is open at least one end in the first direction and is formed as an opening. The shell structure also includes: a cover plate assembly, which is covered on the open sides of the first shell and the second shell, and the cover plate assembly includes a cover plate and an insulating member, the cover plate is sealed and connected to the first shell to cover the open end of the first shell, and the insulating member is sealed and connected to the second shell to cover the opening.

4. The housing structure according to claim 3, characterized in that: The cover plate is connected to the first shell by welding; and / or the insulating member is connected to the second shell by thermal melting.

5. The housing structure according to claim 3, characterized in that: The number of the cover plate assemblies is two, namely a first cover plate assembly and a second cover plate assembly, the first cover plate assembly and the second cover plate assembly are respectively arranged at two ends of the first shell and the second shell in the first direction, An explosion-proof hole is formed on the cover plate of the first cover plate assembly and penetrates the cover plate in the thickness direction, and an explosion-proof valve is provided at the explosion-proof hole. An exhaust hole is formed on the insulating member of the first cover plate assembly and penetrates the insulating member in the thickness direction, and the exhaust hole is opposite to the explosion-proof hole. The first cap plate assembly further includes a sealing film, the sealing film covering the vent hole, and the sealing film is configured to open the vent hole when thermal runaway occurs in the battery cell.

6. The housing structure according to claim 5, characterized in that: The second cover plate assembly is formed with a liquid injection hole penetrating the second cover plate assembly along a thickness direction, the liquid injection hole is communicated with the accommodating cavity, and the second cover plate assembly further includes a sealing nail, the sealing nail seals the liquid injection hole.

7. The housing structure according to any one of claims 1 to 6, characterized in that: Also includes: A support member is supported between the first shell and the second shell.

8. The housing structure according to claim 7, characterized in that: In the thickness direction of the first shell, a distance between the first shell and the second shell is 1 mm to 5 mm.

9. The housing structure according to claim 7, characterized in that: The support member includes a plurality of protrusions, both ends of the protrusions are fixed to the first shell, and the middle portion of the protrusions protrudes toward the second shell and abuts against the second shell through the arc surface of the protrusions.

10. A battery cell, characterized in that: include: The housing structure according to any one of claims 1 to 9.

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