Battery module, method for producing the battery module, and battery pack comprising the battery module

Abstract

A battery module according to one embodiment of the present disclosure includes a cell stack including one or more battery cells, a single frame for accommodating the cell stack, and a thermally conductive resin layer between a lower portion of the cell stack and the single frame, wherein the battery module further includes a spring between an upper portion of the cell stack and the single frame.

Description

Technical Field

[0001] Cross-reference to related applications

[0002] This application claims the benefit of Korean Patent Application No. 10-2019-0069463, filed with the Korean Intellectual Property Office on June 12, 2019, the disclosure of which is incorporated herein by reference in its entirety.

[0003] This disclosure relates to a battery module, a method for manufacturing the battery module, and a battery pack including the battery module. More particularly, this disclosure relates to a battery module capable of adjusting the injection amount of thermally conductive resin, a method for manufacturing the battery module, and a battery pack including the battery module. Background Technology

[0004] In modern society, the daily use of portable devices such as mobile phones, laptops, portable camcorders, and digital cameras has spurred technological development in related fields. Furthermore, in an effort to address air pollution caused by existing gasoline vehicles using fossil fuels, rechargeable batteries are being used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs), thus increasing the demand for rechargeable batteries.

[0005] Currently commercially available rechargeable batteries include nickel-cadmium (NiCd), nickel-metal hydride (NiMH), nickel-zinc (NiZn), and lithium-ion batteries. Among these, lithium-ion batteries have attracted significant attention due to their advantages, such as exhibiting almost no memory effect compared to nickel-based batteries, allowing for free charging and discharging, and possessing a very low self-discharge rate and high energy density.

[0006] This type of lithium secondary battery primarily uses lithium-based oxides and carbonaceous materials as the positive and negative electrode active materials, respectively. The lithium secondary battery includes an electrode assembly and an external material (i.e., a battery casing) that seals and houses the electrode assembly and electrolyte together. In the electrode assembly, positive and negative electrode plates, respectively coated with positive and negative electrode active materials, are arranged such that a separator is placed between the positive and negative electrode plates.

[0007] Generally, based on the shape of the external material, lithium secondary batteries can be classified into can-type secondary batteries in which the electrode assembly is embedded in a metal can, and bag-type secondary batteries in which the electrode assembly is embedded in an aluminum laminate.

[0008] In the case of secondary batteries for small devices, two to three individual battery cells are arranged. However, in the case of secondary batteries for medium to large devices such as automobiles, battery modules in which a large number of individual battery cells are electrically connected are used. These battery modules typically include multiple secondary batteries connected in series and parallel to each other to enhance capacity and output. Furthermore, one or more battery modules can be installed with various control and protection systems such as a battery management system (BMS) and a cooling system to form a battery pack.

[0009] On the other hand, in order to protect the cell stack from external impact, heat or vibration, the battery module may include: a single frame having an open front and rear surface to house the cell stack in an internal space; and an end plate covering the front and rear surfaces of the single frame.

[0010] In this configuration, thermally conductive resin can be injected between the monomer stack and the single frame to form a thermally conductive resin layer, which can be used to transfer heat generated from the monomer stack to the bottom of the battery module.

[0011] However, during the injection of thermally conductive resin, due to tolerances of components in the battery module, more resin than intended may be injected, leading to increased manufacturing costs and thus negatively impacting profitability. Summary of the Invention

[0012] Technical issues

[0013] Embodiments of this disclosure have been proposed to address the above problems, and their object is to provide a battery module capable of being injected with a predetermined amount of thermally conductive resin and a method for preparing the battery module.

[0014] However, the problems to be solved by the embodiments of this disclosure are not limited to the problems described above, and various extensions can be made within the scope of the technical ideas included in this disclosure.

[0015] Technical solutions

[0016] A battery module according to one embodiment of the present disclosure includes: a cell stack including one or more battery cells; a single frame housing the cell stack; and a thermally conductive resin layer located between a lower portion of the cell stack and the single frame, wherein the battery module further includes a spring located between an upper portion of the cell stack and the single frame.

[0017] The spring can push the individual units downwards.

[0018] The battery module may further include a busbar frame, which is housed together with the individual unit stack within a single frame. The busbar frame may include an upper frame located above the individual unit stack, and a spring may be located between the upper frame and the single frame.

[0019] The spring may include at least one of a leaf spring and a cylindrical spring.

[0020] There can be two or more springs.

[0021] The thermally conductive resin layer may include a thermally conductive adhesive material.

[0022] A single frame can have an open shape with both the front and rear surfaces.

[0023] A method for preparing a battery module according to an embodiment of the present disclosure includes: a housing step of housing a stack of cells comprising one or more battery cells in a single frame; and an injection step of injecting thermally conductive resin through an injection hole formed at the lower part of the single frame, wherein the injection step includes the step of causing a spring located between the upper part of the stack of cells and the single frame to push the stack of cells in a direction opposite to the injection direction of the thermally conductive resin.

[0024] The injection process may include the following steps: inverting the single frame so that the injection hole faces upward, and injecting thermally conductive resin.

[0025] The spring may include at least one of a leaf spring and a cylindrical spring.

[0026] Beneficial effects

[0027] According to embodiments of this disclosure, the manufacturing cost of the battery module is reduced because the internal space of the battery module can be reduced by using a spring disposed inside the single frame, thereby allowing a predetermined amount of thermally conductive resin to be injected. Attached Figure Description

[0028] Figure 1 This is a perspective view of a battery module according to an embodiment of the present disclosure;

[0029] Figure 2 yes Figure 1 An exploded 3D view of the battery module;

[0030] Figure 3 It was cut along the cutting line A-A'. Figure 1 A cross-sectional view of the battery module;

[0031] Figure 4 yes Figure 3 A magnified view of part "B";

[0032] Figure 5This is a cross-sectional view illustrating a method for manufacturing a battery module according to an embodiment of the present disclosure; and

[0033] Figure 6 yes Figure 5 A magnified view of part of the "C". Detailed Implementation

[0034] In the following, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings, enabling those skilled in the art to readily implement these embodiments. The present disclosure can be modified in various different ways and is not limited to the embodiments set forth herein.

[0035] Parts irrelevant to the description will be omitted in order to clearly describe this disclosure, and throughout the specification, the same reference numerals denote the same elements.

[0036] Furthermore, the dimensions and thicknesses of each element are arbitrarily shown in the accompanying drawings for ease of description, and this disclosure is not necessarily limited to what is shown in the drawings. The thicknesses of layers, regions, etc., are exaggerated in the drawings for clarity.

[0037] Additionally, it will be understood that when an element (such as a layer, membrane, region, or plate) is referred to as being "on" or "above" another element, it can be located directly on that other element, or there may be intervening elements. Conversely, when an element is referred to as being "directly" located "on" another element, it means that there are no other intervening elements. Furthermore, the terms "on" or "above" mean being positioned above or below a reference portion, and do not necessarily mean being positioned at the upper end of the reference portion in the opposite direction to gravity.

[0038] Furthermore, throughout the specification, when a component is referred to as "including" a certain part, unless otherwise stated, this means that it may further include other parts, rather than exclude other parts.

[0039] Figure 1 This is a schematic perspective view of a battery module 100 according to an embodiment of the present disclosure, and Figure 2 yes Figure 1 Exploded perspective view of battery module 100.

[0040] refer to Figure 1 and Figure 2 According to one embodiment of the present disclosure, a battery module 100 includes: a cell stack 400 including one or more battery cells; a single frame 200 housing the cell stack 400; and a thermally conductive resin layer 700 located between the lower portion of the cell stack 400 and the single frame 200.

[0041] The single frame 200 has an open shape with both the front and rear surfaces, and may have end plates 300 covering the front and rear surfaces.

[0042] In addition, a busbar frame 500 may be provided, which is housed together with the cell stack 400 within a single frame 200. The busbar frame 500 may include an upper frame 510 located at the top of the cell stack 400, a front frame 520 located at the front surface of the cell stack 400, and a rear frame 530 located at the rear surface of the cell stack, wherein busbars 540 connected to the electrode leads of the battery cells constituting the cell stack 400 may be mounted on the front frame 520 and the rear frame 530.

[0043] The thermally conductive resin layer 700 is formed by injecting thermally conductive resin and may include a thermally conductive adhesive material. Specifically, a flowable thermally conductive resin is injected, and then the thermally conductive resin can be cured and formed while in contact with the cell stack 400. That is, the thermally conductive resin can serve to transfer the heat generated from the cell stack 400 to the bottom of the battery module 100 and to fix the cell stack 400 in the battery module 100.

[0044] Meanwhile, a heat sink 800 can be provided on the side surface of the single stack 400, and the heat sink 800 is housed together in the single frame 200.

[0045] Figure 3 It was cut along the cutting line A-A'. Figure 1 A cross-sectional view of the battery module, and Figure 4 yes Figure 3 A magnified view of part "B".

[0046] refer to Figure 3 and Figure 4 The battery module of this embodiment further includes a spring 600 located between the upper part of the cell stack 400 and the single frame 200. More specifically, the spring 600 may be located between the upper frame 510 of the busbar frame positioned at the upper part of the cell stack 400 and the single frame 200.

[0047] The spring 600 can simultaneously push the upper frame 510 and the monomer stack 400 downwards while located between the upper frame 510 and the single frame 200. As a result, the space between the lower part of the monomer stack 400 and the single frame 200 is reduced, and it is possible to prevent the thermally conductive resin injected to form the thermally conductive resin layer 700 from being injected in excessive amounts beyond what is necessary. Finally, since a predetermined amount of thermally conductive resin can be injected, the manufacturing cost is effectively reduced. (Refer to...) Figure 5 and Figure 6 This will be described in detail again.

[0048] Furthermore, in order to ensure that the elastic force of the springs 600 applied to the unit stack 400 is not concentrated in any one part but acts uniformly, there are preferably two or more springs 600. More preferably, the two or more springs 600 are evenly distributed over all areas of the upper surface of the upper frame 510.

[0049] If, during the injection of thermally conductive resin, two or more springs 600 are uniformly distributed across all areas of the upper surface of the upper frame 510 as described above, the elastic force of the springs 600 can act uniformly without biasing to any part of the cell stack 400. By utilizing the balance between the elastic force acting uniformly on the cell stack 400 and the injection pressure of the thermally conductive resin, the thermally conductive resin can be uniformly applied to the entire lower portion of the cell stack 400, and the thermally conductive resin layer 700 can be formed with a constant thickness. Therefore, since the heat generated from the battery cells constituting the cell stack 400 can be constantly transferred throughout the entire area, in addition to the heat dissipation effect, it also exhibits the effect of reducing the temperature deviation between the battery cells constituting the cell stack 400.

[0050] At the same time, if the spring 600 can push the unit stack 400 downwards, its shape is not limited. Therefore, the spring 600 can be as follows: Figure 4 The leaf spring shown is either a cylindrical spring (not shown) or a combination of a leaf spring and a cylindrical spring. However, since springs occupy more space than necessary in the battery module, leaf springs are preferred.

[0051] Figure 5 This is a cross-sectional view showing a method for manufacturing a battery module 100 according to an embodiment of the present disclosure. Figure 6 yes Figure 5 A magnified view of part of the "C".

[0052] Hereinafter, a method for preparing a battery module 100 according to an embodiment of the present disclosure will be described. However, descriptions of portions overlapping with the foregoing will be omitted.

[0053] refer to Figure 5 and Figure 6 The method for preparing the battery module 100 according to this embodiment includes: a housing step: housing a stack of cells 400 including one or more battery cells in a single frame 200; and an injection step: injecting thermally conductive resin through an injection hole 210 formed at the lower part of the single frame 200 to form a thermally conductive resin layer 700.

[0054] First, the single frame 200 may have an open shape with a front surface and a rear surface, and the receiving step may include inserting the single stack 400 into the open front surface or rear surface of the single frame 200.

[0055] Next, in the injection step, the single frame 200 can be inverted so that the injection hole 210 faces upward, and thermally conductive resin can be injected through the injection hole 210. In this case, the spring 600 located between the upper part of the monomer stack 400 (based on the single frame before it is inverted) and the single frame 200 can push the monomer stack in the opposite direction (direction D) to the injection direction of the thermally conductive resin.

[0056] When the single frame 200 is inverted, so that the injection port 210 faces upward, and thermally conductive resin is injected, the monomer stack 400 forms close contact with the bottom (based on the single frame being inverted) due to the weight of the monomer stack 400, and the space for injecting thermally conductive resin is increased, which may cause the problem of injecting too much thermally conductive resin than necessary.

[0057] When thermally conductive resin is injected through injection hole 210, the spring 600 of this embodiment can push the monomer stack 400 in the opposite direction (direction D) to the injection direction of the thermally conductive resin by its elastic force. Therefore, the problem of excessive injection of thermally conductive resin can be solved.

[0058] The inclusion of at least one of leaf springs or cylindrical springs in spring 600, as well as the inclusion of two or more springs 600, will be omitted because this is redundant with the above.

[0059] One or more battery modules according to the above embodiments can be installed together with various control and protection systems such as a battery management system (BMS) and a cooling system to form a battery pack.

[0060] Battery modules or battery packs can be applied to a variety of devices. Specifically, battery modules or battery packs can be applied to transportation vehicles such as electric bicycles, electric vehicles, and hybrid electric vehicles, and can be applied to various devices that use secondary batteries, but are not limited to these.

[0061] Although the preferred embodiments of this disclosure have been described in detail above, the scope of this disclosure is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concepts of this disclosure as defined in the appended claims are also within the scope of the claims.

[0062] Description of reference numerals in the attached figures

[0063] 100: Battery Module

[0064] 200: Single frame

[0065] 210: Injection Hole

[0066] 300: End plate

[0067] 400: Single-unit heap

[0068] 500: Busbar Framework

[0069] 600: Spring

[0070] 700: Thermally conductive resin layer

Claims

1. A battery module, comprising: A cell stack, wherein the cell stack comprises multiple battery cells; A single frame that accommodates the single-unit stack; and A thermally conductive resin layer is located between the lower part of the monomer stack and the single frame. The battery module further includes: A busbar frame, which is housed together with the unit stack in the single frame, the busbar frame including an upper frame located at the top of the unit stack, a front frame located at the front surface of the unit stack, and a rear frame located at the rear surface of the unit stack. An injection hole is formed at the lower part of the single frame, through which thermally conductive resin forming the thermally conductive resin layer is injected; and A spring, located between the upper frame and the single frame of the busbar frame. The spring pushes the monomer stack in a direction opposite to the injection direction of the thermally conductive resin.

2. The battery module according to claim 1, wherein, The spring includes at least one of a leaf spring and a cylindrical spring.

3. The battery module according to claim 1, wherein, The springs are two or more.

4. The battery module according to claim 1, wherein, The thermally conductive resin layer includes a thermally conductive adhesive material.

5. The battery module according to claim 1, wherein, The single frame has an open shape with both the front and rear surfaces.

6. A battery pack comprising at least one battery module according to any one of claims 1-5.

7. A method for preparing a battery module according to any one of claims 1-5, comprising: The housing step involves housing a stack of individual battery cells and a busbar frame together within a single frame. The busbar frame includes an upper frame located at the top of the stack, a front frame located on the front surface of the stack, and a rear frame located on the rear surface of the stack. Injection step: Thermally conductive resin is injected through an injection hole formed at the lower part of the single frame. The injection step includes the following steps: causing a spring located between the upper frame and the single frame of the busbar frame to push the monomer stack in a direction opposite to the injection direction of the thermally conductive resin.

8. The method for preparing a battery module according to claim 7, wherein, The injection step includes the following steps: inverting the single frame so that the injection hole faces upward, and injecting the thermally conductive resin into it.

9. The method for preparing a battery module according to claim 7, wherein, The spring includes at least one of a leaf spring and a cylindrical spring.

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