Battery module and battery pack including the same

Abstract

A battery module according to one embodiment of the present invention comprises: a battery cell stack having a plurality of battery cells stacked thereon; a module frame accommodating the battery cell stack; a busbar frame covering the front and rear surfaces of the battery cell stack; and an end plate covering the busbar frame and coupled to the module frame, wherein a busbar is mounted on the busbar frame and a thin film layer is located between the busbar frame and the end plate.

Description

Technology Field

[0001] The present invention relates to a battery module and a battery pack including the same, and more specifically, to a battery module in which the heat inside the battery module is automatically managed and controlled according to the temperature of the external environment, and a battery pack including the same. Background Technology

[0002] With the increasing technological development and demand for mobile devices, the demand for secondary batteries as an energy source is rapidly increasing. In particular, secondary batteries are attracting significant interest as an energy source not only for mobile devices such as mobile phones, digital cameras, laptops, and wearable devices, but also for power devices such as electric bicycles, electric vehicles, and hybrid electric vehicles.

[0003] While small mobile devices use one or two or three battery cells per device, medium-to-large devices such as automobiles require high output and large capacity. Therefore, medium-to-large battery modules in which multiple battery cells are electrically connected are used.

[0004] Here, battery modules face the problem of degraded output performance when exposed to low-temperature environments. For example, in the case of vehicles equipped with battery modules, there is a problem with degraded battery performance during cold starts. To address this issue, some battery modules incorporate or place indirect heating devices, such as planar heating elements, within the module. However, this entails technical disadvantages, such as increasing the overall thickness and weight of the battery module, as well as economic disadvantages, such as increased manufacturing costs due to the need to add separate control means to manage the planar heating elements. Accordingly, there is a need to develop a battery module that can prevent output degradation even in low-temperature environments while resolving these technical or economic drawbacks. The problem to be solved

[0005] The problem to be solved by the present invention is to provide a battery module in which the heat inside the battery module is automatically managed and controlled according to the temperature of the external environment, and a battery pack including the same.

[0006] The problems that the present invention aims to solve are not limited to those described above, and problems not mentioned will be clearly understood by those skilled in the art from this specification and the attached drawings. means of solving the problem

[0007] A battery module according to one embodiment of the present invention comprises: a battery cell stack having a plurality of battery cells stacked thereon; a module frame accommodating the battery cell stack; a busbar frame covering the front and rear surfaces of the battery cell stack; and an end plate covering the busbar frame and coupled to the module frame, wherein a busbar is mounted on the busbar frame and a thin film layer is located between the busbar frame and the end plate.

[0008] The above thin film layer can come into contact with at least a portion of the surface of the busbar.

[0009] The above thin film layer may be composed of a thin film composition that generates heat at a first temperature.

[0010] The first temperature mentioned above may be a temperature of 10 degrees Celsius or lower.

[0011] The above thin film composition may be made of a CTR (Critical Temperature Resistor) ceramic material.

[0012] The above CTR (Critical Temperature Resistor) ceramic material may include at least one of a composite vanadium oxide-based material, a boron oxide-based material, and a phosphate-based material.

[0013] The above-mentioned complex vanadium oxide-based material is VO2, V2O3, V6O 13At least one of them can be selected.

[0014] The above thin film composition may further include a doping material.

[0015] The above doping material is Mo 4+ , Mo 5+ , Mo 6+ , W 5+ , W 6+ , and Nb 5+ It may include at least one of the following.

[0016] The thin film composition containing the above doping material is heated at a second temperature, and the second temperature may be lower than the first temperature.

[0017] A battery pack according to another embodiment of the present invention includes the battery module described above. Effects of the invention

[0018] According to the embodiments, the present invention includes a thin film layer that is heated to an appropriate temperature level in a low-temperature environment, so that a battery module and a battery pack including the same can automatically manage and control the heat inside the battery module according to the temperature of the external environment.

[0019] The effects of the present invention are not limited to the effects described above, and unmentioned effects will be clearly understood by those skilled in the art from this specification and the accompanying drawings. Brief explanation of the drawing

[0020] FIG. 1 is a perspective view showing a battery module according to an embodiment of the present invention. Figure 2 is an exploded perspective view of the battery module of Figure 1. Figure 3 is a drawing showing a busbar frame located on one side of the battery cell stack of Figure 2. Figure 4 is a drawing showing a busbar frame located on the other side of the battery cell stack of Figure 2. Figure 5 is a diagram showing the heat transfer path in the battery module of Figure 1 with the end plate removed. Specific details for implementing the invention

[0021] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0022] To clearly explain the present invention, parts unrelated to the explanation have been omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0023] Furthermore, the size and thickness of each component shown in the drawings are depicted arbitrarily for convenience of explanation, and thus the present invention is not necessarily limited to what is illustrated. Thicknesses have been enlarged in the drawings to clearly represent various layers and regions. Additionally, for convenience of explanation, the thickness of some layers and regions has been exaggerated in the drawings.

[0024] Furthermore, throughout the specification, when a part is described as “comprising” a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0025] Additionally, throughout the specification, "planar" means when the subject part is viewed from above, and "cross-sectional" means when the cross-section obtained by vertically cutting the subject part is viewed from the side.

[0026] Hereinafter, a battery module according to an embodiment of the present invention will be described. However, the description herein will be based on the front side of the battery module, but is not necessarily limited thereto, and the description may be identical or similar in the case of the rear side.

[0027] FIG. 1 is a perspective view showing a battery module according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the battery module of FIG. 1.

[0028] Referring to FIGS. 1 and 2, a battery module (100) according to one embodiment of the present invention comprises: a battery cell stack (120) in which a plurality of battery cells (110) are stacked; a module frame (300, 400) that accommodates the battery cell stack (120); a busbar frame (131, 135) that covers the front and rear surfaces of the battery cell stack (120); and an end plate (150) that covers the busbar frame (131, 135) and is coupled to the module frame (300, 400).

[0029] Here, the module frame (300, 400) may include a U-shaped frame (300) with the top, front, and rear surfaces open and including the bottom and sides, and an upper plate (400) covering the top of the battery cell stack (120). However, the module frame (300, 400) is not limited thereto and may be replaced with a frame of other shapes, such as an L-shaped frame or a mono frame surrounding the battery cell stack (120) excluding the front and rear surfaces.

[0030] Referring to FIG. 2, in the module frame (300, 400), a thermally conductive resin layer (310) may be formed on the bottom surface of the U-shaped frame (300) that contacts the bottom surface of the battery cell stack (120). Here, the thermally conductive resin layer (310) may be formed by applying a thermally conductive resin onto the bottom surface of the U-shaped frame (300). That is, the thermally conductive resin layer (310) may be formed as the thermally conductive resin, which is applied in advance, hardens before the battery cell stack (120) is mounted on the U-shaped frame (300). However, in the battery module (100) according to another embodiment of the present invention, the thermally conductive resin layer (310) may be omitted as necessary.

[0031] Accordingly, as the thermally conductive resin hardens, the lower surface of the battery cell stack (120) and the U-shaped frame (300) can be stably fixed to each other. In addition, the thermally conductive resin layer (310) can transfer heat from the battery cell stack (120) to the outside, thereby cooling the battery cell stack (120).

[0032] A battery cell stack (120) housed in a module frame (300, 400) comprises a plurality of battery cells (110) stacked therein, and preferably, the battery cells (110) are pouch-type battery cells. The battery cells (110) can be manufactured by housing an electrode assembly in a pouch case made of a laminate sheet including a resin layer and a metal layer, and then heat-sealing the sealing portion of the pouch case. A plurality of such battery cells (110) may be formed, and the plurality of battery cells (110) form a stacked battery cell stack (120) so that they can be electrically connected to each other.

[0034] Below, the busbar frame (131, 135) will be described in detail.

[0035] FIG. 3 is a drawing showing a busbar frame located on one side of the battery cell stack of FIG. 2. FIG. 4 is a drawing showing a busbar frame located on the other side of the battery cell stack of FIG. 2.

[0036] Referring to FIGS. 2 to 4, at least one busbar (141, 145) may be mounted on a busbar frame (131, 135). Here, the busbar (141, 145) electrically connects the electrode leads of a battery cell stack (120) protruding from the busbar frame (131, 135), so that the battery cell stacks (120) stacked in parallel may be electrically connected.

[0037] For example, the busbar frame (131, 135) may include a first busbar frame (131) and a second busbar frame (135). Here, the first busbar frame (131) may be located on the front of the battery cell stack (120), and the second busbar frame (135) may be located on the rear of the battery cell stack. Additionally, the busbar (141, 145) may include a first busbar (141) and a second busbar (145). Here, the first busbar (141) may be mounted on the first busbar frame (131), and the second busbar (145) may be mounted on the second busbar frame (135). However, the same description may be applied even if the positions of the first busbar frame (131) and the second busbar frame (135) are swapped.

[0038] Additionally, a thin film layer (133, 137) is positioned between the busbar frame (131, 135) and the end plate (150). More specifically, a first thin film layer (133) may be positioned between the first busbar frame (131) and the end plate (150), and a second thin film layer (135) may be positioned between the second busbar frame (135) and the end plate (150). However, in a battery module according to another embodiment of the present invention, some of the first thin film layer (133) and the second thin film layer (137) may be omitted.

[0039] Additionally, referring to FIGS. 3 and 4, the thin film layer (133, 137) may be in contact with at least a portion of the surface of the bus bar (141, 145) or coated on at least a portion of the surface of the bus bar (141, 145). More specifically, the first thin film layer (133) may be in contact with at least a portion of the surface of the first bus bar (141) or coated on at least a portion of the surface of the first bus bar (141). Additionally, the second thin film layer (135) may be in contact with at least a portion of the surface of the second bus bar (145) or coated on at least a portion of the surface of the second bus bar (145).

[0040] Accordingly, in the battery module (100) according to the present embodiment, the thin film layer (133, 137) is in direct contact with the bus bar (141, 145), so that the battery cell (110) can be heated through the bus bar (141, 145) in a low-temperature environment, and the output reduction of the battery cell (110) that may occur in a low-temperature environment can be prevented, and the battery performance can also be improved. In addition, heat can be transferred from the battery cell (110) in a room temperature or high-temperature environment, so that the battery cell (110) can be prevented from being heated excessively.

[0041] For example, the thin film layer (133, 137) may be pre-fabricated in the form of a film or sheet and attached to the bus bar (141, 145). Here, the thin film layer (133, 137) may be attached to the bus bar (141, 145) by its own adhesive force, or it may be attached by forming a separate adhesive layer between the thin film layer (133, 137) and the bus bar (141, 145). As another example, the thin film layer (133, 137) may be formed by applying or coating it onto the surface of the bus bar (141, 145). More specifically, the thin film layer (133, 137) may be formed by coating it onto the surface of the bus bar (141, 145) through a conventional thin film coating process such as sol-gel, atomic-layer-deposition (ALD), chemical vapor deposition (CVD), or physical vapor deposition (PVD). However, it is not limited to this, and thin film layers (133, 137) can be formed in various forms.

[0042] Accordingly, the battery module (100) according to the present embodiment includes thin film layers (133, 137), so that the manufacturing process is simple and the manufacturing cost can be reduced without increasing the weight or thickness of the battery module (100).

[0043] Additionally, the thin film layer (133, 137) may be composed of a thin film composition that generates heat at a first temperature. More specifically, the thin film layer (133, 137) generates heat at the first temperature, and the heat generated from the thin film layer (133, 137) is transferred to the battery cell (110) through the bus bar (141, 145), so that the battery cell (110) can be heated to 20 degrees Celsius to 50 degrees Celsius.

[0044] Here, the first temperature may be a temperature of 10 degrees Celsius or lower. More specifically, the first temperature may be a temperature of 5 degrees Celsius or lower. For example, the first temperature may be a temperature of 0 degrees Celsius or lower.

[0045] Accordingly, the thin film layer (133, 137) can generate heat at a temperature within the above-described range, and thus heat can be transferred to the battery cell (110) through the bus bar (141, 145) in contact with the thin film layer (133, 137), thereby allowing the battery cell (110) to rapidly raise its temperature to a predetermined temperature on its own without the input of external thermal energy in a low-temperature environment such as the above-described range. As a result, the output of the battery cell (110) can be prevented in a low-temperature environment and the battery performance can be improved.

[0046] In contrast, if the thin film layer (133, 137) generates heat at a temperature exceeding 10 degrees Celsius, heat may be transferred from the thin film layer (133, 137) to the battery cell (110) even though the battery cell (110) is not exposed to a low-temperature environment to the extent that its output is reduced, and consequently, there is a risk that the battery cell (110) may be excessively heated. In this case, a fire may occur in the battery cell (110).

[0047] Additionally, in the thin film layer (133, 137), the thin film composition may be made of a temperature-dependent variable resistance heating element material. More specifically, the thin film composition may be made of a material having high electrical resistance at low temperatures and low electrical resistance at high temperatures. That is, the heat generated in the thin film layer (133, 137) may be the resistance heat of the thin film composition.

[0048] Accordingly, when the thin film layer (133, 137) is exposed to a room temperature or high temperature environment, the thin film layer (133, 137) does not generate heat, and the electrical resistance of the thin film layer (133, 137) can be maintained at a low level, comparable to that of a busbar current-carrying material. In other words, when the thin film layer (133, 137) is not exposed to a low temperature environment to the extent that the output of the battery cell (110) is reduced, the supply / transfer of thermal energy by the resistance heat of the thin film layer (133, 137) can be limited. In such cases, the thermally conductive resin layer (310) on the bottom surface of the above-described U-shaped frame (300) can perform a cooling function for the battery cell (110).

[0049] For example, the thin film composition may be composed of a CTR (Critical Temperature Resistor) ceramic material. More specifically, the CTR (Critical Temperature Resistor) ceramic material has the characteristic that its electrical resistance changes rapidly due to a change in its crystal structure near the phase transition temperature. The CTR (Critical Temperature Resistor) ceramic material may include at least one of a composite vanadium oxide-based material, a boron oxide-based material, and a phosphate-based material. For example, the composite vanadium oxide-based material may be VO2, V2O3, or V6O 13 At least one of the following may be selected. Additionally, the boron oxide-based material may be B2O3. Additionally, the phosphate-based material may be P2O5.

[0050] Accordingly, in the battery module (100) according to the present embodiment, the thin film layer (133, 137) can act as a self-heating heat source within the battery module (100) due to high resistance heat at low temperatures, and can function as an electrical conductor due to high electrical conductivity at high temperatures.

[0051] Additionally, in the thin film layer (133, 137), the thin film composition may further include a doping material. For example, the thin film composition including the doping material may generate heat at a second temperature, and the second temperature may be lower than the first temperature.

[0052] More specifically, the doping material may include at least one of metal ions such as Mo with a valence of +4 or higher and W with a valence of +5 or higher. More specifically, metal ions such as Mo with a valence of +4 or higher, W with a valence of +5 or higher, and Nb with a valence of +5 or higher have characteristics that control the phase transition temperature and / or the range of resistance change of the thin film composition. As an example, the doping material is Mo 4+ , Mo 5+ , Mo 6+ , W 5+ , W 6+ , and Nb 5+ It may include at least one of the following.

[0053] Accordingly, in the battery module (100) according to the present embodiment, the doping material can be included in the thin film composition constituting the thin film layer (133, 137), so that the heating temperature and resistance change of the thin film composition can be controlled as needed.

[0055] Hereinafter, a heat transfer path according to the thin film layer (133, 137) in the battery module (100) according to the present embodiment will be described in detail.

[0056] Figure 5 is a diagram showing the heat transfer path in the battery module of Figure 1 with the end plate removed.

[0057] Referring to FIG. 5, in the battery module (100) according to the present embodiment, heat within the module frame (300, 400) can flow in a first direction (D1) in a low-temperature environment. More specifically, the low-temperature environment may be an environment that is lower than the first temperature described above. Here, the first direction (D1) can be described as a direction from the thin film layer (133, 137) toward the battery cell stack (120). More specifically, in a low-temperature environment, heat generated from the thin film layer (133, 137) can flow in the first direction (D1) toward the battery cell stack (120), which has a relatively lower temperature.

[0058] Conversely, in a room temperature or high temperature environment, heat within the battery module (100) may flow in a second direction (D2). Here, the second direction (D2) can be described as a direction from the battery cell stack (120) toward the thin film layer (133, 137). More specifically, in a room temperature or high temperature environment, heat generated from the battery cell (110) during the charging and discharging process of the battery module (100) may flow in a second direction (D2) toward the thin film layer (133, 137) which has a relatively lower temperature.

[0059] Accordingly, the battery module (100) according to the present embodiment can automatically switch the heat transfer path according to the temperature change of the external environment of the battery module (100), so that no separate control means is required, the manufacturing process is simplified and the manufacturing cost can also be reduced. In addition, the temperature of the battery cell (110) can be maintained within a predetermined temperature range. That is, the thin film layer (133, 137) can prevent the output performance of the battery cell (110) in a low-temperature environment. In addition, it functions as an electrical conductor in room temperature and high-temperature environments, and the module cooling structure through the thermally conductive resin layer (310) on the bottom surface of the U-shaped frame (300) functions to prevent the ignition phenomenon of the battery cell (110).

[0060] A battery pack according to another embodiment of the present invention includes the battery module described above. Meanwhile, one or more of the battery modules according to the present embodiment may be packaged within a pack case to form a battery pack.

[0061] The battery module and the battery pack containing the same described above can be applied to various devices. Such devices may be applied to means of transportation such as electric bicycles, electric vehicles, and hybrid vehicles, but the present invention is not limited thereto and can be applied to various devices capable of using the battery module and the battery pack containing the same, and this also falls within the scope of the rights of the present invention.

[0062] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention. Explanation of the symbols

[0063] 100: Battery module 110: Battery cell 120: Battery cell laminate 131, 135: Busbar frame 141, 145: Busbar 150: End plate 300, 400: Module Frame

Claims

Claim 1 A battery module comprising: a battery cell stack having a plurality of battery cells stacked thereon; a module frame accommodating the battery cell stack; a busbar frame covering the front and rear surfaces of the battery cell stack; and an end plate covering the busbar frame and coupled to the module frame, wherein a busbar is mounted on the busbar frame, a thin film layer is located between the busbar frame and the end plate, and the thin film layer is coated on at least a portion of the surface of the busbar, and the thin film layer is composed of a thin film composition that generates heat at a first temperature and functions as an electrical conductor above the first temperature. Claim 2 delete Claim 3 delete Claim 4 A battery module according to claim 1, wherein the first temperature is a temperature of 10 degrees Celsius or less. Claim 5 In claim 1, the thin film composition is a battery module made of a CTR (Critical Temperature Resistor) ceramic material. Claim 6 In claim 5, the CTR (Critical Temperature Resistor) ceramic material comprises at least one of a composite vanadium oxide-based material, a boron oxide-based material, and a phosphate-based material, forming a battery module. Claim 7 In paragraph 6, the above-mentioned complex vanadium oxide-based material is VO2, V2O3, V6O 13 A battery module in which at least one of the following is selected. Claim 8 In claim 1, the thin film composition further comprises a battery module including a doping material. Claim 9 In paragraph 8, the doping material is Mo 4+ , Mo 5+ , Mo 6+ , W 5+ , W 6+ , and Nb 5+ including at least one of Battery module. Claim 10 In claim 9, the thin film composition containing the doping material is heated at a second temperature, and the second temperature is lower than the first temperature of the battery module. Claim 11 A battery pack comprising a battery module according to paragraph 1.

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