Battery module and battery comprising the same

Abstract

A battery module according to an embodiment of the present application includes: a battery cell stack including a plurality of battery cells stacked with each other; a module frame to accommodate the battery cell stack; an end plate covering front and rear surfaces of the battery cell stack and coupled to the module frame; a heat sink located below a bottom of the module frame; and at least two cooling ports connected to the heat sink to supply a refrigerant to the heat sink. The end plate includes: a first mounting portion located between a side end portion of the end plate and a cooling port adjacent to the side end portion among the at least two cooling ports and extending in a protruding direction of an electrode lead protruding from the battery cell; and a second mounting portion located between two adjacent cooling ports among the at least two cooling ports and extending in the protruding direction of the electrode lead protruding from the battery cell.

Description

TECHNICAL FIELD

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Korean Patent Application No. 10-2020-0052263, filed on April 29, 2020, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

[0003] The present application relates to a battery module and a battery pack including the same, and more particularly, to a battery module having improved strength and a battery pack including the same. BACKGROUND

[0004] In modern society, as portable devices such as mobile phones, laptop computers, camcorders, and digital cameras are used on a daily basis, technologies related to the above mobile devices have been actively developed. In addition, rechargeable batteries that can be charged and discharged are used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) as a solution to air pollution from existing gasoline vehicles using fossil fuels, and thus the demand for developing rechargeable batteries is increasing.

[0005] Currently commercialized rechargeable batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium rechargeable batteries. Among them, lithium rechargeable batteries are known for their advantages of charge-discharge freedom, extremely low self-discharge rate, and high energy density, compared to nickel-based rechargeable batteries, since they have almost no memory effect.

[0006] These lithium rechargeable batteries mainly use lithium-based oxides and carbon materials as positive active materials and negative active materials, respectively. The lithium rechargeable battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate are coated with positive active materials and negative active materials, respectively, and a separator is interposed between the positive electrode plate and the negative electrode plate, and a battery case for sealing and accommodating the electrode assembly together with an electrolyte.

[0007] Generally, lithium rechargeable batteries can be classified into can-type rechargeable batteries in which an electrode assembly is embedded in a metal can and pouch-type rechargeable batteries in which an electrode assembly is embedded in a pouch of an aluminum laminate, according to the shape of an external material.

[0008] In the case of a rechargeable battery used in a small device, two or three battery cells are provided, but in the case of a rechargeable battery used in a medium to large device such as a car, a battery module in which a plurality of battery cells are electrically connected is used. In such a battery module, a plurality of battery cells are connected in series or in parallel to each other to form a battery cell stack, thereby increasing capacity and power. Further, one or more battery modules 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.

[0009] In the case of a rechargeable battery, when the temperature is higher than a suitable temperature, the performance of the rechargeable battery can be deteriorated, and in a severe case, there is a risk of explosion or fire. In particular, a plurality of rechargeable batteries, i.e., a battery module or a battery pack having battery cells, can have a temperature that is rapidly and severely increased due to heat emitted from a plurality of battery cells accumulated in a narrow space. In other words, in the case of a battery module in which a plurality of battery cells are stacked and a battery pack equipped with such a battery module, high power can be obtained, but heat generated from the battery cells during charging and discharging is not easily removed. If heat dissipation of the battery cells is not properly performed, deterioration of the battery cells is accelerated and the lifespan is shortened, and the possibility of explosion or fire increases.

[0010] Further, a battery module included in a vehicle battery pack can be frequently exposed to direct sunlight and can be subjected to high-temperature conditions, for example, in summer or in a desert region. Accordingly, when the battery module or the battery pack is configured, it can be very important to secure stable and efficient cooling performance.

[0011] To this end, a heat sink for cooling can be integrally formed with the battery module. In this case, the addition of a structure for injecting a refrigerant into the heat sink can cause structurally weak portions. In particular, when the battery module has a large area to increase capacity, the possibility of the occurrence of portions vulnerable to vibration or impact is high, and thus a unit for solving this problem needs to be developed. SUMMARY

[0012] TECHNICAL PROBLEM

[0013] The present application is directed to providing a battery module and a battery pack including the same, which is advantageous in securing cooling performance while improving structural stability in such a large battery module.

[0014] However, the problems to be solved by the exemplary embodiments of the present application are not limited to the above-mentioned problems and can be variously extended within the scope of the technical idea included in the present application.

[0015] TECHNICAL SOLUTION

[0016] According to an exemplary embodiment of the present application, a battery module includes: a battery cell stack in which a plurality of battery cells are stacked; a module frame that accommodates the battery cell stack; an end plate that covers front and rear surfaces of the battery cell stack and is coupled to the module frame; a heat sink located below a bottom of the module frame; and at least two cooling ports connected to the heat sink to supply a refrigerant to the heat sink, wherein the end plate includes: a first mounting portion located between a side end portion of the end plate and a cooling port adjacent to the side end portion among the at least two cooling ports and extending in a protruding direction of an electrode lead protruding from the battery cell; and a second mounting portion located between two adjacent cooling ports among the at least two cooling ports and extending in the protruding direction of the electrode lead protruding from the battery cell.

[0017] Each of the first mounting portion and the second mounting portion can include a through-hole formed to pass through the first mounting portion and the second mounting portion in a direction perpendicular to the protruding direction.

[0018] One of the cooling ports can be a refrigerant injection port, and another of the cooling ports can be a refrigerant discharge port.

[0019] The module frame can include at least two module frame protrusions formed by a portion of a bottom of the module frame protruding from positions corresponding to the at least two cooling ports.

[0020] A bottom surface of the module frame can constitute an upper plate of the heat sink, and the bottom of the module frame can be in contact with the refrigerant.

[0021] The heat sink can include a recessed portion recessed from a plate-shaped main body, and the recessed portion and an upper plate formed by the bottom surface of the module frame can be coupled to form a flow path of the refrigerant.

[0022] The recessed portion can be a U-shaped tube, and the bottom portion can be located at an open upper side of the U-shaped tube.

[0023] According to another exemplary embodiment of the present application, a battery pack includes at least one battery module and a battery pack frame located below a heat sink to accommodate the battery module.

[0024] Each of the first mounting portion and the second mounting portion can include a through-hole formed to pass through the first mounting portion and the second mounting portion in a direction perpendicular to the protruding direction, the battery pack frame can include a fastening hole at a position corresponding to the through-hole, and the battery pack frame can include a mounting bolt coupled to the fastening hole of the battery pack frame through the through-hole.

[0025] The first mounting portion can be two, and the portions at which the first mounting portion and the second mounting portion are coupled to the fastening hole can be three or more.

[0026] According to another exemplary embodiment of the present invention, the device includes at least one of the aforementioned battery packs.

[0027] Beneficial effects

[0028] According to an exemplary embodiment, a battery module and a battery pack including the battery module can be provided. The battery module has improved cooling performance even over a large area and improved structural stability against vibration and shock through an integrated battery module structure of module frame and heat sink. Attached Figure Description

[0029] Figure 1 This is a perspective view of a battery module according to an exemplary embodiment of the present invention.

[0030] Figure 2 yes Figure 1 An exploded perspective view of the battery module.

[0031] Figure 3 It was observed along the z-axis. Figure 1 A bottom-view perspective view of the battery module.

[0032] Figure 4 This is a partial perspective view of a battery pack according to an exemplary embodiment of the present invention. Detailed Implementation

[0033] In the following, exemplary embodiments of the invention will be described in detail with reference to the accompanying drawings to enable those skilled in the art to practice the invention. The invention may be embodied in various different forms and is not limited to the examples described herein.

[0034] To describe the invention more clearly, parts irrelevant to the description may be omitted, and the same or similar parts may be indicated by the same reference numerals throughout the specification.

[0035] Furthermore, for ease of explanation, the dimensions and thicknesses of each component shown in the accompanying drawings may be arbitrarily depicted; therefore, the present invention is not necessarily limited to the exemplary embodiments shown in the drawings. In the drawings, for clarity, the thicknesses of individual layers, regions, etc., may be exaggerated. In the drawings, for ease of explanation, the thicknesses of some layers and regions may be exaggerated.

[0036] Also, it will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. Also, when an element is referred to as being "on" or "under" another element, it can be on or under the other element, and the like, and not necessarily in the opposite direction of gravity, unless otherwise stated.

[0037] Also, unless explicitly described to the contrary, the word "comprise" and variations such as "comprises" or "comprising" will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

[0038] Throughout the specification, when referred to as "in a plan view", it refers to viewing a target element from above, and when referred to as "in a sectional view", it refers to a section formed by vertically cutting a target element from a side.

[0039] Figure 1 is a perspective view of a battery module according to an exemplary embodiment of the present application, Figure 2 is Figure 1 is an exploded perspective view of the battery module of Figure 3 is a perspective view of the battery module of Figure 1 is a bottom perspective view of the battery module of

[0040] Referring to Figures 1 to 3 According to an exemplary embodiment of the present application, a battery module 100 includes a battery cell stack 120 in which a plurality of battery cells 110 are stacked, a module frame 200 that accommodates the battery cell stack 120, an end plate 400 that is located on both of the opening sides (y-axis direction and the opposite direction thereof) of the module frame 200 corresponding to each other to cover the battery cell stack 120, and a cooling port 500 for cooling the battery module 100. In addition, the battery module 100 can include a heat sink 300 located below a bottom 210a of the module frame 200, and can include at least two cooling ports 500 that supply and discharge a refrigerant to and from the heat sink 300.

[0041] The battery cell 110 can be a pouch-type battery cell. Such a pouch-type battery cell can be formed by accommodating an electrode assembly in a pouch case including a laminated sheet of a resin layer and a metal layer and then heat-sealing the outer periphery of the pouch case. In this case, the battery cell 110 can be formed in a rectangular sheet shape structure. The battery cell 110 can be configured as a plurality, and the plurality of battery cells 110 are stacked to be electrically connected to each other to form the battery cell stack 120. Specifically, as Figure 2As illustrated, the plurality of battery cells 110 can be stacked in a direction parallel to the x-axis.

[0042] The module frame 200 that accommodates the battery cell stack 120 can include an upper cover 220 and a U-shaped frame 210.

[0043] The U-shaped frame 210 can include a bottom 210a and two side portions 210b extending upward from both ends of the bottom 210a. The bottom 210a can cover a lower surface of the battery cell stack 120 (in a direction opposite to the z-axis), and the side portions 210b can cover both side surfaces of the battery cell stack 120 (in the x-axis direction and the opposite direction thereof).

[0044] The upper cover 220 can be formed in a plate-shaped structure that covers the lower surface covered by the U-shaped frame 210 and the upper surface (z-axis direction) except for the two side surfaces. The upper cover 220 and the U-shaped frame 210 can be coupled to each other in a state where their corresponding edge portions contact each other by welding or the like, thereby forming a structure that covers the battery cell stack 120 upward and downward and left and right. The battery cell stack 120 can be physically protected by the upper cover 220 and the U-shaped frame 210. To this end, the upper cover 220 and the U-shaped frame 210 can include a metal material having a predetermined strength.

[0045] Meanwhile, although not specifically illustrated, the module frame 200 according to a modified example can be a single frame in the form of a metal plate in which an upper surface, a lower surface, and two side surfaces are integrated. That is, the module frame 200 can be manufactured to have a structure in which an upper surface, a lower surface, and two side surfaces are integrated by extrusion molding, rather than a structure in which the U-shaped frame 210 and the upper cover 220 are coupled to each other.

[0046] The module frame 200 according to the present exemplary embodiment can include a module frame protrusion 211 formed such that the bottom 210a of the module frame 200 extends through the end plate 400. Here, the refrigerant introduced and discharged through the cooling port 500 connected to the upper surface of the module frame protrusion 211 can be supplied to and discharged from the heat sink 300 through the module frame protrusion 211.

[0047] The module frame protrusion 211 and the cooling port 500 connected thereto can be disposed to be spaced apart from each other along one side of the module frame 200 (e.g., a side thereof parallel to the x-axis direction of the drawing). The bottom 210a of the module frame 200 constitutes an upper plate of the heat sink 300, and the recessed portion 340 of the heat sink 300 and the bottom 210a of the module frame 200 can form a flow path of the refrigerant.

[0048] Specifically, the heat sink 300 can be formed below the module frame 200, and the heat sink 300 can include a lower plate 310 forming a skeleton of the heat sink 300 and directly coupled to the bottom 210a of the module frame 200 by welding or the like, and a recess 340 as a path through which a refrigerant flows. Also, the heat sink 300 can include a heat sink protrusion 300P protruding from a side of the heat sink 300 to a portion where the module frame protrusion 211 is located.

[0049] The heat sink protrusion 300P and the module frame protrusion 211 can be directly coupled to each other by welding or the like. The recess 340 of the heat sink 300 corresponds to a portion where the lower plate 310 is recessed downward. The recess 340 can be a U-shaped tube in a cross-section cut in an x-y plane perpendicular to a direction in which the refrigerant flow path extends, and the bottom 210a can be located on an open upper side of the U-shaped tube. As the heat sink 300 comes into contact with the bottom 210a, a space between the recess 340 and the bottom 210a becomes an area through which the refrigerant flows, i.e., a flow path of the refrigerant. Accordingly, the bottom 210a of the module frame 200 can be in direct contact with the refrigerant.

[0050] There is no particular limitation on a manufacturing method of the recess 340 of the heat sink 300, but a U-shaped recess 340 having an open upper side can be formed by providing a structure recessed with respect to a plate-shaped heat sink. Also, the bottom 210a of the module frame 200 can be joined to a portion of the lower plate 310 where the recess 340 is not formed in the heat sink 300 by welding. In this way, through the cooling structure of the bottom 210a of the module frame 200 and the heat sink 300, an effect of supporting a load of the battery cell stack 120 accommodated in the module frame 200 and enhancing the rigidity of the battery module 100, and the above-described effect of improving the cooling performance can be obtained. Also, the lower plate 310 and the bottom 210a of the module frame 200 can be sealed by welding or the like so that the refrigerant can flow in the recess 340 formed inside the lower plate 310 without leaking. Meanwhile, the refrigerant as a cooling medium can be cooling water, but is not particularly limited.

[0051] Meanwhile, although not shown, a thermally conductive resin layer including a thermally conductive resin can be located between the bottom 210a of the module frame 200 and the battery cell stack 120. Figure 4 The thermally conductive resin layer can be formed by applying the thermally conductive resin to the bottom 210a and curing the applied thermally conductive resin.

[0052] The thermally conductive resin can include a thermally conductive adhesive material, specifically, can include at least one of a silicone material, a polyurethane material, and an acrylic material. The thermally conductive resin can be in a liquid phase at the time of coating, but is cured after being coated to fix one or more battery cells 110 constituting the battery cell stack 120. In addition, the thermally conductive resin can have excellent thermal conductivity to quickly transfer heat generated in the battery cell 110 to the lower side of the battery module.

[0053] The end plate 400 can be formed to be located on both open sides (y-axis direction and the opposite direction thereof) of the module frame 200 corresponding to each other to cover the battery cell stack 120. The end plate 400 can physically protect the battery cell stack 120 and other electrical components from external impact. At the same time, although not specifically shown, a busbar frame in which a busbar is installed and an insulating cover for electrical insulation can be located between the battery cell stack 120 and the end plate 400.

[0054] In addition, the end plate 400 can include a plurality of mounting portions 410 and 420 to fix the battery module 100 to a battery pack housing of a battery pack to be described later. The plurality of mounting portions 410 and 420 can protrude and extend from the other side opposite to the side on which the battery cell stack 120 is located with respect to the end plate 400. That is, the plurality of mounting portions 410 and 420 are formed to extend in the protruding direction (y-axis direction) of the electrode lead wire protruding from the battery cell 100 included in the battery cell stack 120.

[0055] Among them, the first mounting portion 410 can be positioned adjacent to both end portions (i.e., both end portions in the x-axis direction of the figure) of the end plate 400. Both end portions of the end plate 400 can be stably fixed by the first mounting portion 410. The first mounting portion 410 can be provided on both of the pair of end plates 400 provided at both end portions of the module frame 200.

[0056] The second mounting portion 420 is provided corresponding to between two adjacent cooling ports 500 among the at least two cooling ports 500. For example, as shown in the figure, when two cooling ports 500 are provided, the second mounting portion 420 can be provided between the two cooling ports 500.

[0057] In the related art, only the end of the end plate 400 is configured to be fixed without the second mounting portion 420, but as the area of the battery module 100 increases, the portion vulnerable to vibration and impact further increases, thereby increasing the possibility of damage. In particular, since the heat spreader 300 is integrally formed on the bottom 210a of the module frame 200, structural deformation accompanied by the module frame protrusion 211 and the like protruding from the bottom 210a of the module frame 200, and the structural weakness can be more problematic in the portion where the structure is deformed. As the number of connection portions between components (for example, the connection portion between the cooling port 500 and the module frame protrusion 211 and the coupling portion between the lower plate 310 of the heat spreader 300 and the module frame 200) increases, damage due to vibration and impact can increase.

[0058] However, in the exemplary embodiment of the present application, since the second mounting portion 420 is further provided between the adjacent cooling ports 500 as described above, even in the structure in which the cooling port 500 is integrally formed with the heat spreader 300 and the structure having a large area, the battery module 100 can be stably fixed to increase the strength against vibration and impact, and damage to the portion in which the cooling port 500 and the heat spreader 300 are connected to the module frame 200 and the like can be prevented.

[0059] Further, in the drawings, the cooling port 500 is formed to correspond to only one of the pair of end plates 400, but the cooling port 500 can be formed on both sides, and further, even in the end plate 400 in which the cooling port 500 is not formed, the second mounting portion 420 can be additionally provided to particularly supplement the structural weakness due to the large area. Further, the second mounting portion 420 can be further provided according to the need for strength improvement without particular limitation.

[0060] One or more battery modules 100 according to the present exemplary embodiment 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 1000.

[0061] Hereinafter, a battery pack according to an exemplary embodiment of the present application will be described with reference to the accompanying drawings. Figure 4 A battery pack according to an exemplary embodiment of the present application will be described.

[0062] Figure 4 is a partial perspective view of a battery pack according to an exemplary embodiment of the present application.

[0063] Referring to Figure 4 , the battery pack 1000 of the present application includes the battery module 100 and a battery pack frame 1100 accommodating the battery module 100. The battery pack frame 1100 can be located below the heat spreader 300 of the battery module 100.

[0064] The battery module 100 can be fixed to the battery pack frame 1100 through the first mounting portion 410 and the second mounting portion 420 included in the end plate 400. That is, the first mounting portion 410 and the second mounting portion 420 include through-holes that pass through in a direction perpendicular to a direction in which the end plate 400 protrudes (i.e., in the z-axis direction in the drawing). Also, the battery pack frame 1100 includes fastening holes at positions corresponding to the through-holes. In a state in which the through-holes and the fastening holes are aligned, the battery module 100 is fixed to the battery pack frame 1100 by fastening mounting bolts 700 that pass through the through-holes and the fastening holes.

[0065] Here, two first mounting portions 410 can exist in one end plate 400 to correspond to two side end portions, and at least one second mounting portion 420 can be provided between adjacent cooling ports 500, and thus, more than three fixing points can be present in one end plate 400 at which the first mounting portion 410 and the second mounting portion 420 are coupled to the fastening holes of the battery pack frame 1100 with each other. In this way, when the battery module 100 is fixed to the battery pack frame 1100, fixing points are additionally provided in portions in which structural weakness can occur, and thus, damage to the battery module 100 due to vibration or impact or sagging caused by the weight of the battery module 100 itself in a large-area, large-capacity battery module 100 can be prevented.

[0066] In exemplary embodiments, terms indicating directions such as front, rear, left, right, up, and down are used, but these terms are only for convenience of explanation and can vary according to the position of an object or the position of an observer.

[0067] The battery module or the battery pack can be applied to various devices. Specifically, the battery module or the battery pack can be applied to a vehicle such as an electric bicycle, an electric vehicle, a hybrid vehicle, etc., but is not limited thereto, and can be applied to various devices that can use a rechargeable battery.

[0068] Although the present application has been described with reference to exemplary embodiments, it is to be understood that the present application is not limited to the disclosed exemplary embodiments, but is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

[0069] <LEGEND>

[0070] 200: module frame

[0071] 211: module frame protrusion

[0072] 300: heat sink

[0073] 400: end plate

[0074] 410: first mounting portion

[0075] 420: second mounting portion

[0076] 500: cooling port

[0077] 700: mounting bolt

Claims

1. A battery module comprising: a cell stack in which a plurality of battery cells are stacked; a module frame that accommodates the cell stack and covers the cell stack up, down, left, and right; a pair of end plates that cover both open sides of the module frame and front and rear surfaces of the cell stack and are joined to the module frame; a heat sink located below a bottom of the module frame; and at least two cooling ports connected to the heat sink to supply refrigerant to the heat sink, wherein one of the pair of end plates includes: a first mounting portion located between a side end portion of one of the pair of end plates and a cooling port adjacent to the side end portion among the at least two cooling ports, and extending in a protruding direction of an electrode lead protruding from the battery cell; and a second mounting portion located between two adjacent cooling ports among the at least two cooling ports, and extending in the protruding direction of the electrode lead protruding from the battery cell, wherein the battery module has improved cooling performance and improved structural stability against vibration and impact. Each of the first and second mounting portions includes a through-hole formed to pass through the first and second mounting portions in a direction perpendicular to the protruding direction.

2. The battery module of claim 1, wherein, One of the cooling ports is a refrigerant injection port, and the other of the cooling ports is a refrigerant discharge port.

3. The battery module of claim 1, wherein, 4.The battery module of claim 1, wherein the module frame includes at least two module frame protrusions formed by a portion of a bottom of the module frame protruding from positions corresponding to the at least two cooling ports. 5.The battery module of claim 1, wherein a bottom surface of the module frame constitutes an upper plate of the heat sink, and the bottom of the module frame is in contact with the refrigerant. 6.The battery module of claim 5, wherein the heat sink includes a recessed portion recessed from a plate-shaped body, and the recessed portion and the upper plate formed by the bottom surface of the module frame are joined to form a flow path of the refrigerant. 7.The battery module of claim 6, wherein the recessed portion is a U-shaped tube, and the bottom is located at an open upper side of the U-shaped tube. 8.A battery pack comprising: at least one battery module of claim 1; and a battery pack frame located below the heat sink to accommodate the battery module. 9.The battery pack of claim 8, wherein each of the first and second mounting portions includes a through-hole formed to pass through the first and second mounting portions in a direction perpendicular to the protruding direction, the battery pack frame includes a fastening hole at a position corresponding to the through-hole, and the battery pack frame includes a mounting bolt joined to the fastening hole of the battery pack frame through the through-hole. ​ ​ 10. The battery pack of claim 9, wherein, the first mounting portion is two, and the first mounting portion and the second mounting portion are coupled with the fastening hole at three or more positions.

11. An apparatus comprising the battery pack of claim 8.

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