Battery case, battery module including same, battery pack and automobile, and method for manufacturing battery case

Abstract

A battery case, a battery module including the battery case, a battery pack, and a vehicle, and a manufacturing method of the battery case are disclosed. The battery case according to an embodiment of the present invention includes a lower case in which a plurality of battery cells are accommodated, and an upper case combined with the lower case, and at least one of the upper case and the lower case is provided with an insert nut, and at least one of the upper case and the lower case is formed with a pin hole at a position adjacent to the insert nut, and the pin hole is blocked.

Description

[Technical Field]

[0001] This application claims priority based on Korean Patent Application No. 10-2021-0142194, filed on October 22, 2021, and the entire contents disclosed in the specification and drawings of that application are incorporated herein by reference.

[0002] The present invention relates to a battery case, a battery module, a battery pack and an automobile including the same, and a method for manufacturing the battery case, and more particularly to a battery case with improved waterproof performance, a battery module, a battery pack and an automobile including the same, and a method for manufacturing the battery case. [Background technology]

[0003] The recent remarkable development of technology and the increase in demand for mobile devices have led to a rapid increase in the need for secondary batteries as energy sources. While nickel-cadmium batteries or hydrogen-ion batteries have traditionally been used as secondary batteries, lithium secondary batteries have recently come into widespread use due to their extremely low self-discharge rate, high energy density, and the ability to be freely charged and discharged, as opposed to nickel-based batteries, which have almost no memory effect.

[0004] This type of lithium secondary battery mainly uses a lithium-based oxide and a carbon material as the positive and negative electrode active materials, respectively, and includes a secondary battery cell in which a separator is sandwiched between positive and negative electrode plates coated with the positive and negative electrode active materials, and an exterior material, such as a battery case, that encloses the secondary battery cell together with an electrolyte.

[0005] Lithium secondary batteries consist of a positive electrode, a negative electrode, a separator sandwiched between them, and an electrolyte. They are classified as lithium ion batteries (LIBs), polymer lithium ion batteries (PLIBs), etc., depending on the positive and negative electrode active materials used. Typically, the electrodes of these lithium secondary batteries are formed by applying a positive or negative electrode active material to a current collector, such as an aluminum or copper sheet, mesh, film, or foil, and then drying the applied material. Many types of secondary batteries include a case that can protect the battery cells, a battery module in which multiple battery cells are housed in the case, and a battery pack containing multiple battery modules.

[0006] Here, waterproofing grades are determined according to the degree of waterproofing of the case, and when the waterproofing grade is high, it is necessary to use a case to prevent water leakage. Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, the technical problem to be solved by the present invention is to provide a battery case that prevents water leakage from the case and improves waterproof performance, a battery module, a battery pack and an automobile including the same, and a method for manufacturing the battery case. [Means for solving the problem]

[0008] According to one aspect of the present invention, a battery case can be provided that includes a lower case that houses a plurality of battery cells and an upper case that is combined with the lower case, wherein an insert nut is provided on at least one of the upper case and the lower case, and a pin hole is formed in at least one of the upper case and the lower case at a position adjacent to the insert nut, and the pin hole is blocked.

[0009] The pin hole may be formed by a pin for supporting the insert nut when at least one of the upper case and the lower case is manufactured.

[0010] At least one of the upper case and the lower case may be manufactured using a mold, the pin may be formed in the mold itself, and at least one of the upper case and the lower case may be formed by injection molding a metal insert nut and plastic.

[0011] Furthermore, a protrusion may be formed on the inside of at least one of the upper case and the lower case, the pin hole may be formed on the inside of the protrusion, and a heating member may be provided to heat the protrusion and seal the pin hole.

[0012] Meanwhile, according to another aspect of the present invention, a battery module including the above-described battery case may be provided, a battery pack including the above-described battery case may be provided, and further, a vehicle including the above-described battery case may be provided.

[0013] Meanwhile, according to yet another aspect of the present invention, there may be provided a method for manufacturing a battery case, including the steps of: placing an insert nut made of a metal material on a plastic material; fabricating at least one of a lower case accommodating a plurality of battery cells and an upper case combined with the lower case by injection molding using a mold; forming a pin hole at a position adjacent to the insert nut; and sealing the pin hole.

[0014] The pin hole may also be formed by a pin formed in the mold itself to support the insert nut.

[0015] The method for manufacturing the battery case may include forming a protrusion on the inside of at least one of the upper case and the lower case, and forming the pin hole on the inside of the protrusion.

[0016] Furthermore, the manufacturing method of the battery case may include a step of using a heating member to heat the protrusion and seal the pin hole. [Effects of the Invention]

[0017] According to one aspect of the present invention, the pinholes formed inside the case are blocked, preventing water leakage from the case, thereby improving waterproof performance. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a schematic overall perspective view of a battery case according to an embodiment of the present invention; [Figure 2] FIG. 2 is a cross-sectional view taken along the line AA′ in FIG. [Figure 3] 3 is an enlarged view of part B of FIG. 2, showing the state in which the pin of FIG. 2 has been removed. [Figure 4] 10A to 10C are diagrams illustrating a process in which pin holes of a battery case are closed according to an embodiment of the present invention. [Figure 5] 10A to 10C are diagrams illustrating a process in which pin holes of a battery case are closed according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and claims should not be construed as being limited to their general or dictionary meanings, but should be construed as being in accordance with the meaning and concept of the technical concept of the present invention, based on the principle that the inventor himself can appropriately define the concept of terms in order to best describe the invention. Therefore, it should be understood that the embodiment described in this specification and the configuration shown in the drawings are merely the most preferred embodiment of the present invention, and do not represent the entire technical concept of the present invention, and therefore various equivalents and modifications that can be substituted therefor may exist at the time of filing this application.

[0020] In the drawings, the size of each component or specific parts constituting the component may be slightly exaggerated, omitted, or illustrated schematically for ease of explanation and clarity. Therefore, the size of each component does not fully reflect the actual size. Furthermore, if a detailed description of related publicly known functions or configurations is deemed to be likely to unnecessarily obscure the gist of the present invention, such detailed description will be omitted.

[0021] The terms "coupled" or "connected" as used herein include not only cases where one member is directly coupled or connected to another member, but also cases where one member is indirectly coupled or connected to another member via a joint member.

[0022] FIG. 1 is a schematic overall perspective view of a battery case according to one embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line A-A' in FIG. 1, FIG. 3 is an enlarged view of portion B in FIG. 2, showing a state in which the pin in FIG. 2 has been removed, and FIGS. 4 and 5 are views showing a process in which the pin hole of a battery case according to one embodiment of the present invention is sealed.

[0023] Referring to the figure, the battery case according to one embodiment of the present invention includes a lower case 100 and an upper case 200.

[0024] 1, a plurality of battery cells 300 are housed in a lower case 100. An upper case 200 is combined with the lower case 100.

[0025] The battery cell 300 may be cylindrical, prismatic, or pouch-shaped, but for ease of explanation, the following description will be given assuming that the battery cell 300 is cylindrical.

[0026] The cylindrical battery cell 300 includes an electrode assembly, for example, a jelly-roll-shaped electrode assembly, a cylindrical housing that accommodates an electrolyte together with the electrode assembly, a positive electrode terminal formed, for example, on the upper part of the housing, and a negative electrode terminal formed, for example, on the lower part of the housing.

[0027] The electrode assembly may have a structure in which a positive electrode and a negative electrode are stacked with a separator sandwiched between them and wound into a jelly roll shape. A positive electrode lead (not shown) is attached to the positive electrode and connected to a positive electrode terminal, for example, at the top of the housing, and a negative electrode lead (not shown) is attached to the negative electrode and connected to a negative electrode terminal, for example, at the bottom of the housing. A cylindrical center pin (not shown) may be inserted into the center of the electrode assembly. This center pin (not shown) fixes and supports the electrode assembly and may function as a passage for releasing gas generated by internal reactions during charge / discharge and operation.

[0028] The upper case 200 and the lower case 100 surround the entire cylindrical battery cell 300, thereby protecting the battery cell 300 from external vibrations and shocks.

[0029] The upper case 200 and the lower case 100 can be formed in various shapes, for example, a rectangular parallelepiped shape, but the shapes of the cases (lower case 100, upper case 200) are not limited to this.

[0030] The upper case 200 and the lower case 100 can be manufactured by plastic injection molding, and the cases can be manufactured as a single unit or as a detachable type.

[0031] The upper case 200 and the lower case 100 may have through-holes (not shown) through which the connector elements or terminal elements can be exposed to the outside. That is, the connector elements or terminal elements can be electrically connected to a predetermined external part or member, and the through-holes can be formed in the case so that such electrical connection is not hindered by the case.

[0032] An insert nut 400 may be provided in at least one of the upper case 200 and the lower case 100. For ease of explanation, the following description will be limited to an embodiment in which the insert nut 400 is provided in the upper case 200. However, such a limited explanation does not narrow the scope of the right.

[0033] The insert nut 400 may be attached to the upper case 200 in a variety of ways. For example, the upper case 200 may be formed by injection molding a metal insert nut 400 and plastic. For example, the upper case 200 may be manufactured by injection molding using a mold.

[0034] Here, during injection molding, there is a risk that the insert nut 400 will move from a preset position due to the injection pressure, resulting in a defect. To prevent this, a pin 500 formed in the mold itself can be provided to support the insert nut 400.

[0035] 2, to prevent defects during injection molding, pins 500 formed in the mold itself support the insert nut 400. The number of pins 500 can be changed in various ways. However, in FIG. 2, the mold is omitted and only the pins 500 are shown.

[0036] Referring to Figure 3, after injection molding is completed, the mold is removed, and the pin 500 formed in the mold itself is also removed, forming a pin hole 210 at a position adjacent to the insert nut 400 in the upper case 200, for example, at the position of the pin 500 that supported the insert nut 400 in the upper case 200.

[0037] That is, the pin hole 210 is formed by a pin 500 formed in the mold itself for supporting the insert nut 400 when the upper case 200 is produced by injection molding.

[0038] If waterproofing is not an issue, it does not pose much of a problem if pinholes 210 are formed in upper case 200 after injection molding is completed. However, if a waterproof case is to be manufactured, there is a risk of water leakage through the pinholes 210, so the pinholes 210 must be sealed.

[0039] In other words, the battery case according to one embodiment of the present invention can be used without blocking the pin hole 210 if waterproofing is not required, but if waterproofing is required, the pin hole 210 must be blocked before use.

[0040] Referring to Fig. 3, a protrusion 220 may be formed on the inside of the upper case 200, and a pin hole 210 may be formed inside the protrusion 220. Referring to Fig. 4, a heating member 600 heats the protrusion 220 to seal the pin hole 210 and form a sealed portion 230. Here, the heating member 600 may be a thermal welding rod, but the present invention is not limited thereto.

[0041] That is, when the heating member 600 heats and presses the protrusion 220, the protrusion 220 melts and forms a sealing portion 230 that seals the pinhole 210, as shown in Fig. 5. This has the effect of preventing water leakage through the pinhole 210 and improving waterproof performance.

[0042] Meanwhile, a battery module (not shown) according to an embodiment of the present invention may include the battery case (lower case 100, upper case 200) according to an embodiment of the present invention as described above. As described above, a plurality of battery cells 300 may be accommodated in the battery case (lower case 100, upper case 200) to form a battery module.

[0043] Meanwhile, a battery pack (not shown) according to an embodiment of the present invention may include a battery case (lower case 100, upper case 200) according to an embodiment of the present invention. The battery pack according to an embodiment of the present invention may also include one or more of the battery modules described above. The battery pack may further include a housing for accommodating the battery modules, various devices for controlling charging and discharging of the battery modules, such as a battery management system (BMS), a current sensor, a fuse, etc.

[0044] Meanwhile, a vehicle (not shown) according to an embodiment of the present invention may include a battery case (lower case 100, upper case 200) according to an embodiment of the present invention. Also, a vehicle according to an embodiment of the present invention may include the above-described battery module or battery pack, and the battery pack may include the battery module.

[0045] Here, the term "automobile" includes predetermined automobiles that are designed to use electricity, such as electric automobiles and hybrid automobiles.

[0046] Hereinafter, the operation and effects of the method for manufacturing a battery case according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0047] However, explanations common to the above explanations also apply to the battery case manufacturing method, and explanations common to the contents explained in the battery case manufacturing method also apply to the battery case, battery module, battery pack, and automobile described above.

[0048] First, a metal insert nut 400 is placed in a plastic material. The insert nut 400 can be made from a variety of metals, and has a screw thread 410 formed inside.

[0049] Next, a mold is prepared, and the upper case 200 is manufactured by injection molding dissimilar materials of plastic and metal. As described above, the manufacturing method of the battery case will be described with emphasis on the upper case 200.

[0050] Then, when the mold is removed, a pin hole 210 is formed adjacent to the insert nut 400. The pin hole 210 is formed by a pin 500 formed in the mold itself, and the pin 500 is provided to support the insert nut 400 during injection molding.

[0051] Here, a protrusion 220 is formed on the inside of the upper case 200 , and the pin hole 210 is formed on the inside of the protrusion 220 .

[0052] The pin holes 210 can then be sealed in a variety of ways, for example, as shown in FIG. 4, a heating element 600 heats the protrusions 220 to seal the pin holes 210, as shown in FIG.

[0053] In this manner, the pinholes formed inside the case are blocked, preventing water leakage from the case, thereby improving the waterproof performance.

[0054] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited to these, and it goes without saying that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention pertains within the technical spirit of the present invention and the scope of equivalents of the claims. [Industrial Applicability]

[0055] The present invention relates to a battery case, a battery module including the same, a battery pack and an automobile, and a method for manufacturing the battery case, and is particularly applicable to industries related to secondary batteries. [Explanation of symbols]

[0056] 100 Lower case (battery case) 200 Upper case (battery case) 210 pin hole 300 battery cells 400 Insert Nut

Claims

1. a lower case housing a plurality of battery cells; an upper case combined with the lower case; Including, An insert nut is provided in at least one of the upper case and the lower case, a pin hole is formed in at least one of the upper case and the lower case at a position adjacent to the insert nut, The pin hole is blocked, a protrusion is formed on the inside of at least one of the upper case and the lower case, and the pin hole is formed on the inside of the protrusion, A battery case in which a heating member heats the protrusion to seal the pin hole.

2. The battery case according to claim 1 , wherein the pin hole is formed by a pin for supporting the insert nut when at least one of the upper case and the lower case is fabricated.

3. at least one of the upper case and the lower case is manufactured using a mold; The pin is formed in the mold itself; The battery case according to claim 2 , wherein at least one of the upper case and the lower case is formed by injection molding the insert nut made of a metal material and plastic.

4. A battery module including a battery case described in any one of claims 1 to 3.

5. A battery pack comprising a battery case described in any one of claims 1 to 3.

6. An automobile comprising a battery case described in any one of claims 1 to 3.

7. A step of placing a metal insert nut on a plastic material; A step of producing at least one of a lower case accommodating a plurality of battery cells and an upper case combined with the lower case by injection molding using a mold; forming a pin hole adjacent to the insert nut; the pinhole is blocked; A method for manufacturing a battery case, comprising: The method for manufacturing a battery case, wherein the insert nut is provided in at least one of the upper case and the lower case.

8. The method for manufacturing a battery case according to claim 7 , wherein the pin hole is formed by a pin formed in the mold itself for supporting the insert nut.

9. The method for manufacturing a battery case according to claim 8 , further comprising forming a protrusion on the inside of at least one of the upper case and the lower case, and forming the pin hole on the inside of the protrusion.

10. The method for manufacturing a battery case according to claim 9 , further comprising the step of using a heating member to heat the protrusion to seal the pin hole.

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