CN116998048A

CN116998048A - Cooling member, and battery module and battery pack including same

Info

Publication number: CN116998048A
Application number: CN202280021362.1A
Authority: CN
Inventors: 曹永范; 柳载旼; 辛殷圭; 金昇俊; 柳尚贤
Original assignee: LG Energy Solution Ltd
Current assignee: LG Energy Solution Ltd
Priority date: 2021-07-22
Filing date: 2022-07-22
Publication date: 2023-11-03
Also published as: KR20230077973A

Abstract

According to one embodiment of the present application, a cooling member positioned on top of a battery cell stack in which a plurality of battery cells are stacked includes: a top plate; a bottom plate and cooling water contained in an inner space between the top plate and the bottom plate, wherein the bottom plate includes a first portion in which a vulnerable portion is formed and a second portion in which the vulnerable portion is not formed, and a thickness value of the first portion is smaller than a thickness value of the second portion.

Description

Cooling member, and battery module and battery pack including same

Technical Field

Cross Reference to Related Applications

The present application claims the benefits of korean patent application No. 10-2021-0096683 filed on 7 months 22 in 2021 and korean patent application No. 10-2021-0165252 filed on 26 months 11 in 2021, which are incorporated herein by reference.

The present disclosure relates to a cooling member, a battery module and a battery pack including the cooling member, and more particularly, to a cooling member that prevents cascading thermal runaway, a battery module and a battery pack including the cooling member.

Background

In modern society, as portable devices such as mobile phones, notebook computers, video cameras, and digital cameras are used in daily life, development of technologies in the fields related to the above-mentioned mobile devices has been stimulated. In addition, chargeable/dischargeable secondary batteries are used as power sources for Electric Vehicles (EVs), hybrid Electric Vehicles (HEVs), plug-in hybrid electric vehicles (P-HEVs), and the like in an attempt to solve air pollution and the like caused by existing gasoline vehicles using fossil fuels. Accordingly, there is an increasing demand for developing secondary batteries.

Current commercial secondary batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries. Among them, lithium secondary batteries are attracting attention because they have advantages such as free charge and discharge and having a very low self-discharge rate and high energy density.

Meanwhile, in the case of a secondary battery for a small-sized device, two to three battery cells are used, but in the case of a secondary battery for a middle-or large-sized device such as an automobile, a middle-or large-sized battery module in which a large number of battery cells are electrically connected is used. Since the middle-or large-sized battery module is preferably manufactured to have as small a size and weight as possible, a prismatic battery, a pouch-shaped battery, etc., which can be stacked with high integration and have a small weight with respect to capacity, are mainly used as the battery cells of the middle-or large-sized battery module.

Meanwhile, the battery cells mounted on the battery module may generate a large amount of heat during the charge and discharge processes. If the temperature becomes higher than the proper temperature due to overcharge or the like, performance may deteriorate. If the temperature rises too high, there is a risk of explosion or fire. If a fire phenomenon occurs inside the battery modules, high temperature heat, gas, or flame may be emitted to the outside of the battery modules, wherein the heat, gas, spark, or flame emitted from one battery module may be transferred to other adjacent battery modules within the battery pack, which may cause cascading thermal runaway within the battery pack.

In order to prevent such thermal runaway, the conventional battery module is equipped with a water injection system that suppresses a fire by injecting coolant through a nozzle if the fire is confirmed in the battery module. However, injection of coolant or the like from a tank located outside the battery module or the battery pack requires a plurality of processes, such as checking whether a fire has occurred, determining whether to inject coolant, and transferring coolant, which makes it difficult to find the right time to extinguish the fire.

Therefore, there is a need for a new technology for rapidly suppressing thermal runaway by injecting coolant into the correct place at the correct time when a fire occurs inside the battery module or the battery pack.

Disclosure of Invention

Technical problem

An object of the present disclosure is to provide a cooling member, which can inject a coolant at the right time and place when a fire occurs inside a battery module or a battery pack, and a battery module and a battery pack including the same.

However, the problems to be solved by the embodiments of the present disclosure are not limited to the above-described problems, but may be variously expanded within the scope of the technical ideas included in the present disclosure.

Technical proposal

According to an embodiment of the present disclosure, there is provided a cooling member located in an upper portion of a battery cell stack in which a plurality of battery cells are stacked, the cooling member including: an upper plate, a lower plate, and a coolant contained in an inner space between the upper plate and the lower plate, wherein the lower plate includes a first portion in which a vulnerable portion is formed and a second portion in which the vulnerable portion is not formed, and wherein a thickness value of the first portion is smaller than a thickness value of the second portion.

The vulnerable portion has a long side and a short side, and the long side may extend along a stacking direction of the battery cells.

The thickness value of the first portion may be less than or equal to half the thickness value of the second portion.

The thickness of the first portion may be 0.03 to 0.07mm.

The vulnerable portion includes a first vulnerable portion and a second vulnerable portion spaced apart from the first vulnerable portion, and thickness values of the first vulnerable portion and the second vulnerable portion may be substantially the same.

The lower plate may be formed by combining a first layer and a second layer having different thicknesses from each other, the thickness of the first portion may correspond to the thickness of the first layer, and the thickness of the second portion may correspond to the thickness of the first layer and the second layer.

One of the first and second layers includes a cladding metal.

At least one of the upper plate, the first layer, and the second layer includes a clad metal.

The first and second layers may be joined by a brazing process.

The upper plate, the first layer and the second layer may be joined by a brazing process.

The upper plate includes a curved portion, a peak of which may correspond to the first portion, and a trough of which may correspond to the second portion.

According to another embodiment of the present disclosure, there is provided a battery module including the above-mentioned cooling member.

The upper plate of the cooling member may be integrated with the upper surface of the module frame forming the outer shape of the battery module.

According to another embodiment of the present disclosure, there is provided a cooling member located in an upper portion of a battery cell stack in which a plurality of battery cells are stacked, the cooling member including: a lower plate at which a plurality of openings are formed; a body providing a flow path for a coolant; and a fixing member that fixes the lower plate and the main body, wherein at least one cooling hose is mounted on the main body, and wherein the cooling hose is melted or broken at a predetermined temperature or pressure or higher.

The cooling hose may be positioned to correspond to the opening of the lower plate.

The cooling hose may have a shape extending along a longitudinal direction of the cooling member.

The cooling hose may be made of a material having a melting point of 300 ℃ or less.

The main body may be provided with a receiving portion for receiving the cooling hose.

Both ends of the cooling hose in the longitudinal direction may be connected to both ends of the receiving portion in the longitudinal direction, respectively.

A small shelf extending in a longitudinal direction of the cooling member is formed at a center of the lower plate, and the main body may be mounted on the lower plate at a position where the small shelf is not formed.

The fixing member may be provided in a belt shape and positioned in parallel with a width direction of the cooling member.

The fixing member may include end coupling parts coupled with both ends of the lower plate in the width direction and a central coupling part coupled with a center of the lower plate in the width direction.

The end coupling portion and the central coupling portion may be formed to have a step difference from other portions of the fixing member.

The cooling member further comprises an inlet port and an outlet port for injecting a coolant into the interior space, wherein the inlet port and the outlet port are connected with an external heat exchanger, and wherein the coolant of the cooling member can circulate through the inlet port and the outlet port.

The body may have a branched shape divided into portions corresponding to the inlet port and the outlet port, respectively.

According to yet another embodiment of the present disclosure, there is provided a battery pack including the above-mentioned cooling member.

The battery pack may include battery modules having an open structure.

The upper plate of the cooling member may be integrated with the upper surface of the battery pack frame forming the external shape of the battery pack.

Advantageous effects

According to the embodiments of the present disclosure, when a fire occurs inside the battery module or the battery pack, the cooling member is partially opened and coolant is injected at an appropriate place, thereby rapidly suppressing the internal fire of the battery module or the battery pack and preventing continuous thermal runaway.

The effects of the present disclosure are not limited to the above-mentioned effects, and still other effects not described above will be clearly understood by those skilled in the art from the description of the appended claims.

Drawings

Fig. 1 is a perspective view illustrating a cooling member according to an embodiment of the present disclosure;

fig. 2 is a view showing an upper plate included in the cooling member shown in fig. 1;

fig. 3 is a view showing a lower plate included in the cooling member shown in fig. 1;

fig. 4 is a view showing a modification of the lower plate included in the cooling member shown in fig. 1;

FIG. 5 is a view showing an example of the section A-A of FIG. 3;

fig. 6 is a view illustrating an example of a cooling member provided in a battery cell stack according to an embodiment of the present disclosure;

Fig. 7 is an enlarged view of region B of fig. 6, which is a view for explaining a change in the lower plate when a battery cell catches fire;

FIG. 8 is a cross-sectional view showing an example of a cooling member shown according to an embodiment of the present disclosure;

FIG. 9 is a view showing another example of the section A-A of FIG. 3;

fig. 10 is a view illustrating another example of a cooling member provided in a battery cell stack according to an embodiment of the present disclosure;

fig. 11 is an enlarged view of region C of fig. 10, which is a view for explaining a change in the lower plate when a battery cell catches fire;

FIG. 12 is a cross-sectional view illustrating another example of a cooling member according to an embodiment of the present disclosure;

FIG. 13 is a cross-sectional view illustrating a cooling member according to another embodiment of the present disclosure;

fig. 14 is an exploded perspective view illustrating a battery pack according to an embodiment of the present disclosure;

fig. 15 is a perspective view of a battery module included in the battery pack according to fig. 14;

fig. 16 is a perspective view illustrating a cooling member according to another embodiment of the present disclosure;

FIG. 17 is a top view showing the cooling member shown in FIG. 16;

FIG. 18 is a top view of a lower plate included in the cooling member shown in FIG. 16;

FIG. 19 is a top view of a body included in the cooling member shown in FIG. 16;

fig. 20 is a view showing a coupled state of a lower plate, a main body, and a cooling hose included in the cooling member shown in fig. 16;

FIG. 21 is a view of the cooling member of FIG. 17 taken along line A-A showing coolant flow into and out of the body and cooling hose; and is also provided with

Fig. 22 is a sectional view taken along the line A-A of the cooling member shown in fig. 17, illustrating injection of a coolant through the cooling hose when the battery cell catches fire.

Detailed Description

Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement them. The present disclosure may be modified in various different ways and is not limited to the embodiments set forth herein.

Portions irrelevant to the description will be omitted to clearly describe the present disclosure, and like reference numerals denote like elements throughout the description.

Further, in the drawings, for convenience of description, the size and thickness of each element are arbitrarily illustrated, and the present disclosure is not necessarily limited to what is shown in the drawings. In the drawings, the thickness of layers, regions, etc. are exaggerated for clarity. In the drawings, the thickness of some layers and regions are exaggerated for convenience of description.

Furthermore, it will be understood that when an element such as a layer, film, region or sheet is referred to as being "on" or "over" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, it means that there are no other intervening elements present. Further, the term "on" or "above" means disposed above or below the reference portion, and does not necessarily mean disposed on the upper end portion of the reference portion toward the opposite direction of gravity. Meanwhile, similarly to the case described as being located "on" or "above" another portion, the case described as being located "under" or "below" another portion will also be understood with reference to the above-mentioned matters.

Further, since the upper/lower surfaces of a specific member may be differently determined according to which direction is used as a reference direction, the "upper surface" or "lower surface" used herein is defined to mean two surfaces facing each other in the z-axis of the member.

Furthermore, throughout the specification, when a portion is referred to as "comprising" or "including" a particular component, this means that the portion can also include other components without excluding other components, unless otherwise specified.

Further, in the entire specification, when referred to as "plane …", this means that the target portion is viewed from the upper side, and when referred to as "cross section …", this means that the target portion is viewed from the side of the cross section that is vertically sectioned.

Next, a cooling member according to an embodiment of the present disclosure will be described.

Fig. 1 is a perspective view illustrating a cooling member according to an embodiment of the present disclosure. Fig. 2 is a view showing an upper plate included in the cooling member shown in fig. 1. Fig. 3 is a view showing a lower plate included in the cooling member shown in fig. 1. Fig. 4 is a view showing a modification of the lower plate included in the cooling member shown in fig. 1.

Referring to fig. 1, the cooling member 500 described in the present embodiment may be provided to reduce the internal temperature of a battery module or a battery pack including battery cells. The cooling member 500 may be a water-cooled cooling member 500 into which a refrigerant or coolant is injected. By providing the cooling member 500 in a water-cooling manner, the cooling efficiency of the cooling member 500 can be uniformly maintained, and the battery cells within the battery module or the battery pack can be uniformly cooled.

The coolant used in the cooling member 500 may use one of known coolants or a mixture thereof, and if the heat of the battery cells can be emitted by moving along the flow path inside the cooling member 500, any of the known coolants may be used. However, as described below, since the coolant of the cooling member 500 may be sprayed toward the battery cells, it is desirable that the coolant not contain a combustible material so as not to promote flames or explosion of the battery cells. Alternatively, even if some additives of a combustible material must be included to improve the function of the coolant, the amount of the additives may be such that secondary explosion of the pouch-type battery cell can be prevented and at the same time serve as an antifreezing agent to prevent the coolant from freezing. More specifically, the coolant may include water. Here, the coolant may contain an antifreeze liquid for lowering the freezing point of water in addition to water. Further, as the antifreeze liquid contained in the coolant, an electrically insulating antifreeze agent having electrically insulating properties may be used.

The cooling member 500 may be disposed on one surface of the battery cell stack to radiate heat of the battery cells. The cooling member 500 may be arranged in parallel with the stacking direction of the battery cell stack so as to be positioned close to the plurality of battery cells of the battery cell stack. Specifically, the cooling member 500 may be located on the upper portion of the battery cell stack (in the +z-axis direction of fig. 14).

The size of the cooling member 500 may be matched to the size of a battery cell stack in which the cooling member 500 is used. In one example, the cooling member 500 may be disposed to correspond to one cell stack, wherein the length of the cooling member 500 may be matched to the length of the cell stack, or may be formed to be greater or smaller with a slight margin, and the width of the cooling member 500 may be matched to the width of the cell stack, or may be formed to be greater or smaller with a slight margin. In another example, the cooling member 500 may be disposed to correspond to a plurality of battery cell stacks, wherein the length and width of the cooling member 500 may be matched to those of the plurality of battery cell stacks, or may be formed to be larger or smaller with a slight margin. Here, the cooling member 500 may be located at the inside of the battery module, but it may also be located at the inside of the battery pack 1000 from the outside of the battery module (see fig. 14).

The cooling member 500 may include: an upper plate 510 and a lower plate 520 forming the outer shape of the cooling member 500; and an inlet/outlet port 530 for injecting coolant into the interior of the cooling member 500.

The cooling member 500 may be formed by coupling edges of the upper plate 510 and the lower plate 520. A sealing part 540 formed by coupling edges of the upper plate 510 and the lower plate 520 may be located at an edge portion of the cooling member 500. The coolant may be contained between the upper plate 510 and the lower plate 520 coupled in the cooling member 500, or circulated between the upper plate 510 and the lower plate 520.

The coolant may be supplied through inlet ports 530 disposed side by side and discharged to outlet ports 530. The inlet port 530 and the outlet port 530 may be disposed side by side in parallel on one end side of the cooling member 500. This may be used to simplify the design regarding inflow and discharge of coolant supplied from the outside of the battery module or the battery pack. Furthermore, this may be used to minimize the temperature difference between the perimeter of the inlet port 530 and the perimeter of the outlet port 530. Specifically, the coolant flowing into the inlet port 530 may have a minimum temperature, and the coolant discharged to the outlet port 530 may have a maximum temperature. Accordingly, when the inlet/outlet ports 530 are disposed adjacent to each other, mutual heat exchange occurs, so that temperature deviation of the entire coolant flowing through the inner space of the cooling member can be minimized. Accordingly, by arranging the inlet/outlet ports 530 side by side, the cooling member 500 can have uniform heat dissipation performance as a whole. Further, the inlet port 530 or the outlet port 530 may be made of aluminum. The inlet port 530 or the outlet port 530 may be bonded to the upper plate 510 or the lower plate 520 by welding such as brazing.

A flow path forming groove 550 may be formed in the cooling member 500. Since the flow path forming groove 550 is provided in the cooling member 500, the flow of the coolant supplied to the cooling member 500 can be determined. The flow path forming grooves 550 may be formed in plurality, and the plurality of flow path forming grooves 550 may be disposed along a straight line parallel to the longitudinal direction of the cooling member 500. The flow path forming grooves 550 may be sequentially formed at the center of the cooling member 500 in the longitudinal direction of the cooling member 500 except for a predetermined region, whereby the flow of the coolant may be formed in a U shape. The flow of the coolant injected through the inlet port 530 of the cooling member 500 may be restricted by the flow path forming groove 550. As coolant flows along the U-shape, coolant injected through the inlet port 530 may be discharged to the outlet port 530 positioned side by side with the inlet port 530. Specifically, the U-shaped flow path through which the coolant flows may include: a first flow path extending from the inlet port 530 along a line parallel to a longitudinal direction of the cooling member 500; a second flow path extending along a curve rotated in a clockwise or counterclockwise direction at a terminal end of the first flow path; and a third flow path extending toward the outlet port 530 along a straight line parallel to the longitudinal direction of the cooling member 500 at a terminal end of the second flow path.

A deformation preventing groove 560 may be formed in the cooling member 500. Since the deformation preventing groove 560 is provided in the cooling member 500, deformation of the shape of the cooling member 500 by the coolant can be prevented. For example, when coolant is injected into the cooling member 500, the injected coolant may be concentrated in 1/2 space of the cooling member 500 by forming a groove 550 across the flow path in the center. A large pressure may be applied to the remaining 1/2 space before the coolant moves into the space through the U-shaped flow path, whereby at least a portion of the cooling member 500 may be expanded or the cooling member 500 may be damaged. When the deformation preventing grooves 560 are formed in the flow path of the cooling member 500, the coolant is temporarily concentrated, and thus, even if a large pressure acts on a specific area, the deformation caused thereby can be minimized. The deformation preventing grooves 560 may be partially provided at intervals in a U-shaped flow path through which the coolant flows in the cooling member 500. The deformation preventing groove 560 may be disposed between the flow path forming groove 550 and the sealing part 540 in the width direction of the cooling member 500. The specific position of the deformation preventing groove 560 may be appropriately set so as to correspond to the flow rate and the flow velocity of the coolant without excessively obstructing the inflow of the coolant through the inlet port 530. Here, the width direction of the cooling member 500 may be a direction parallel to the short side of the cooling member 500. Further, here, the longitudinal direction of the cooling member 500 may be a direction parallel to the long side of the cooling member 500.

Further, a protrusion extending from one side of the cooling member 500 and sequentially disposed along the longitudinal direction of the cooling member 500 may be formed in the periphery of the cooling member 500. As shown in fig. 14, which will be described later, the protrusion may be provided to contact or be adjacent to an electrode lead of each cell stack or a bus bar connected to the electrode lead. Electrode leads or bus bars that provide electrical connection in a battery module or a battery pack are constructions that are prone to heat generation. Therefore, when the above-mentioned protrusions facilitate heat dissipation of the electrode leads or the bus bars, the temperature rise of the battery cells can be more effectively prevented.

Referring to fig. 2, the upper plate 510 is provided in a plate shape. The central portion of the upper plate 510 is recessed or depressed to have a step difference from the edge portion. The upper plate 510 may have a concave shape with respect to a cross section in the width direction. This may be used to form an inner space by the step difference so that the upper plate 510 accommodates coolant. Here, the width direction of the upper plate 510 may be a direction parallel to the short side of the upper plate 510. However, the upper plate 510 may be formed in a different manner from that shown in fig. 2, and when the lower plate 520 includes a vulnerable portion 522 or the like to provide a space containing coolant, the upper plate 510 may also be provided to have an overall flat shape.

Referring to fig. 3, the lower plate 520 of the cooling member 500 may have a shape generally similar to the upper plate 510. The lower plate 520 may also be provided in a plate shape. The lower plate 520 may be formed such that a central portion thereof is recessed or depressed to have a step difference from an edge portion. The lower plate 520 may have a concave shape based on a cross section in a width direction, thereby forming an inner space for accommodating coolant. However, the lower plate 520 is not necessarily provided in a concave shape, but may be provided in an overall flat shape according to the shape of the upper plate 510 or the volume of coolant to be contained. Here, the width direction of the lower plate 520 may be a direction parallel to the short side of the lower plate 520.

In addition, the lower plate 520 may have a frangible portion 522 described later, so that one surface of the lower plate 520 may have a partially recessed groove. When the groove is positioned toward the inside of the cooling member 500, that is, when the groove is formed on the upper surface of the lower plate 520, a coolant may be contained in the groove.

When the cooling member 500 is disposed at the upper portion of the battery cell, the lower plate 520 may be a portion of the cooling member 500 that is positioned closest to the battery cell. Accordingly, the lower plate 520 may be preferably made of a material having high thermal conductivity so as to promote heat dissipation of the battery cells. In addition, in order to improve the overall heat dissipation performance of the cooling member 500, the upper plate 510 of the cooling member 500 may also be made of a material having high thermal conductivity. The upper plate 510 and the lower plate 520 for forming the outer shape of the cooling member 500 may be made of a metal having high rigidity, and specific examples thereof include aluminum, gold, silver, copper, platinum, alloys containing these, and the like.

Meanwhile, as described above, when a fire occurs in the battery cells, it may be effective to inject a liquid such as a coolant into the battery module or the battery pack in order to effectively suppress the fire. The liquid tank within the battery module or the battery pack may have a problem of increasing the volume of the battery module and the battery pack. Therefore, conventionally, separate water tanks are provided outside the battery module and the battery pack, and only when it is confirmed by the sensor that the ignition of the battery cells occurs, a coolant or the like is injected into the battery module or the battery pack through a nozzle or the like extending from the water tanks.

However, the water tanks provided outside the battery module and the battery pack have a problem in that the volume thereof is large, and the user must also manage them separately. Furthermore, the conventional water injection system must be equipped with a separate control unit or communication unit for determining whether to inject the coolant, must cause errors in its operation, and must undergo many determination processes even though it is normally operated, which requires a lot of time. Even after deciding to inject the coolant, if the path from the water tank to the battery cells inside the battery module or the battery pack is somewhat long, it is difficult to rapidly supply the coolant from the water tank to the battery cells, and therefore, it is difficult for the conventional water injection system to suppress the rapid continuous thermal runaway phenomenon.

Accordingly, hereinafter, the lower plate 520 of the cooling member 500 according to the present embodiment, which may be partially opened when the battery cell catches fire by having a portion that does not endure heat or temperature, will be described in more detail.

Referring to fig. 3 and 4, the lower plate 520 described in this embodiment may include a frangible portion 522. "vulnerable portion" may refer to a portion that is more susceptible to breakage by heat or pressure than other portions of the lower plate 520. The vulnerable portion 522 may be a portion having a relatively smaller thickness value than other portions of the lower plate 520. In particular, the lower plate 520 may have a first portion referred to as a frangible portion 522 and a second portion that does not form the frangible portion 522, wherein the second portion may have a thickness that is greater than the thickness of the first portion. The thickness value of the first portion may be less than or equal to half the thickness value of the second portion. The frangible portion 522 has a thickness value that is slightly less than the other portions so that it can be penetrated relatively easily by heat or pressure.

The vulnerable part 522 may be formed to extend along the stacking direction of the battery cells. The longitudinal direction (y-axis) of the vulnerable portion 522 may be a direction in which a length (long side) extends, and may be a direction parallel to the stacking direction of the battery cells 110. The width direction (x-axis) of the vulnerable portion 522 may be a direction perpendicular to the stacking direction of the battery cells 110. Since it is impossible to predict whether the battery cells 110 among the battery cells will cause fire, the vulnerable portion 522 may be formed to correspond to all the battery cells located under the cooling member 500. The vulnerable portion 522 may be formed over the entire length region of the cooling member 500. Here, as shown in fig. 3, the vulnerable portion 522 may be disposed on a straight line parallel to the stacking direction of the battery cells, and as shown in fig. 4, two or more vulnerable portions 522 may be disposed along a straight line parallel to the stacking direction of the battery cells.

The frangible portions 522 can be positioned one after the other in the width direction (x-axis). Here, the width of the vulnerable portion 522 may be differently designed according to the intention of a designer. For example, the frangible portion 522 can have a relatively wide width. In another example, the frangible portion 522 can have a relatively narrow width. The narrower frangible portion 522 can be formed continuously.

The frangible portion 522 may be positioned to correspond to the portion most likely to generate heat between the cells. For example, the electrode leads of the battery cells may be portions that are easily heated due to the concentration of movement of electrons. In order to cope with the heat generation or explosion of the electrode leads, the vulnerable part 522 may be disposed on the electrode leads of the battery cells.

Fig. 5 is a view showing an example of the A-A section of fig. 3.

Referring to fig. 5, the cross-section of the frangible portion 522 shown can have various shapes. Here, as shown in fig. 3, a cross section of the vulnerable portion 522 can be obtained by sectioning the cooling member 500 shown with reference to the xz plane.

The vulnerable portion 522 is a portion having different thicknesses in the lower plate 520, and a first portion where the vulnerable portion 522 is not formed and a second portion where the vulnerable portion 522 is formed are connected vertically, so that a portion of the lower plate 520 may have a square sectional shape as shown in fig. 5 (a). Further, when a slope is formed on the connection surface between the first and second portions, a portion of the lower plate 520 may have a triangular sectional shape as shown in fig. 5 (b) or a trapezoidal sectional shape as shown in fig. 5 (d). When the connection surface between the first and second portions is formed to have curvature, a portion of the lower plate 520 may have a circular cross section as shown in fig. 5 (c). Meanwhile, the sectional shape of the lower plate 520 is not limited by the above example according to the formed vulnerable portion 522, and thus various modifications may be made in consideration of ease of design and the like. Considering that the vulnerable portion 522 must be broken by heat or temperature, there are cases where it may be desirable that the vulnerable portion 522 includes as many thin portions as possible: other shapes shown in fig. 5 are more desirable than those shown in fig. 5 (b). However, the temperature and pressure for fracture may be affected by factors such as thickness, physical properties, shape, etc., and thus the shape shown in fig. 5 (b) may not necessarily be superior to other shapes shown in fig. 5.

Fig. 6 is a view illustrating an example of a cooling member provided in a battery cell stack according to an embodiment of the present disclosure. Fig. 7 is an enlarged view of region B of fig. 6, which is a view for explaining a change in the lower plate when a battery cell catches fire. Fig. 8 is a cross-sectional view showing an example of a cooling member shown according to an embodiment of the present disclosure. Meanwhile, in fig. 8, the upper plate 510 is previously illustrated omitted.

Referring to fig. 6 and 7, a battery cell stack 120 in which battery cells 110 are stacked in one direction is received in a module frame or a battery pack frame, and a cooling member 500 may be disposed on the battery cell stack 120.

The cooling member 500 includes an upper plate 510 and a lower plate 520, and a coolant may be accommodated in a space between the upper plate 510 and the lower plate 520. The lower plate 520 of the cooling member 500 is positioned toward the battery cell stack 120, and the vulnerable part 522 formed on the lower plate 520 may extend in the stacking direction of the battery cells 110 so as to correspond to the battery cells 110 of the battery cell stack 120. Fig. 6 and 7 show cross sections of positions where the vulnerable portion 522 is formed, and the upper surface of the lower plate 520 on which the vulnerable portion 522 is not formed may be hidden by a coolant. Accordingly, the upper surface of the second portion of the lower plate 520 is indicated by the dashed lines in fig. 6 and 7.

When a fire occurs in the first battery cell 110a due to overcharge or the like, a first portion of the vulnerable portion 522 located above the first battery cell 110a may be broken due to heat, gas, spark, flame, or the like generated from the first battery cell 110a. By opening the first portion, the coolant received in the inner space of the cooling member 500 may be injected toward the first battery cell 110a where the fire occurs. In this way, when thermal runaway occurs in the first battery cell 110a, the vulnerable portion 522 is partially opened so that coolant is immediately supplied to the first battery cell 110a. Accordingly, the fire of the first battery cell 110a may be rapidly suppressed, and thermal runaway may be rapidly suppressed, as compared to a conventional water injection system.

At this time, as shown on the right side of fig. 7, the heat or pressure generated from the battery cell 110 locally heats or pressurizes the vulnerable portion 522, thereby opening the first portion. Thus, in the frangible portion 522, only the first portion is opened, while the other portions of the frangible portion 522 can remain in a closed state. If a portion of the vulnerable portion 522 other than the first portion is kept in a closed state, the coolant inside the cooling member 500 may concentrate and flow out to the first portion. Accordingly, the coolant may be injected into the first battery cell 110a in a concentrated manner, compared to a conventional water injection system, thereby maximizing the efficiency of fire extinguishing due to water injection.

Meanwhile, if an excessive amount of coolant is injected into the battery module or the battery pack, although it is possible to quickly suppress a fire in the first battery cell 110a, the coolant is injected into other battery cells 110, so that a plurality of battery cells 110 that are normally operated may be damaged. Therefore, the amount of the coolant to be injected needs to be designed in advance to an appropriate level.

The amount of coolant may be preset to a level sufficient to suppress a fire that has occurred in some of the battery cells 110. Here, the number of the battery cells 110, which is the basis for calculating the amount of the coolant, may be the number of the battery cells 110 to which thermal runaway is generally transmitted during internal ignition, and in particular, the number may be four to six, or one to two more or one to two less than four to six. In addition, since the coolant sprayed toward the first battery cell 110a is vaporized during the fire suppression process and evaporated into water vapor, the coolant may not remain in the battery module or the battery pack, and damage to the normal battery cell 110 by the remaining moisture may be prevented. Meanwhile, since the amount of the coolant received in the cooling member 500 may be pre-calculated and designed to match the energy released from the battery cells 110, the cooling member 500 of the present embodiment may be applied in various ways without being limited by the type (such as a cylinder type, a prismatic type, or a pouch type) or capacity of the battery cells 110.

At this time, the coolant of the cooling member 500 may or may not flow and circulate from the outside. In a specific example, the cooling member 500 may be connected with an external tank, and the coolant flowing in from the external tank circulates in the cooling member 500 through the inlet/outlet port 530 and may be discharged back to the external tank. Thereby, since the temperature of the coolant can be appropriately maintained, the heat radiation performance of the cooling member 500 can be improved.

In another specific example, the coolant inside the cooling member 500 may not further flow in. Before the cooling member 500 is mounted on the battery module or the battery pack, the coolant is injected, and when the battery module or the battery pack is used, additional injection and discharge may not be performed. When the cooling member 500 is discontinuously connected to the external case and is incorporated into the battery pack or the battery module, the external case is omitted, and therefore, the overall structure may be simplified, which is efficient in terms of space utilization. In addition, the cost and time required for maintaining/managing the external box can be reduced. Also in this case, the inlet/outlet port 530 may be removed from the cooling member 500 to simplify the design. Since the cooling member 500 contains water having a large specific heat, heat transfer between the battery cells 110 in the battery module can be effectively prevented even if circulation is not performed. Further, if an internal fire occurs in the battery module or the battery pack, only a predetermined amount of coolant may be sprayed to the battery cells 110, and therefore, problems caused by the coolant remaining in the battery module or the battery pack may be minimized.

When the coolant of the cooling member 500 does not flow into the external case in this manner, the amount of coolant injected into the battery module or the battery pack during the internal ignition of the first battery cell 110a may be limited to the entire coolant contained in the cooling member 500. Further, when a partition wall or a groove is provided in the cooling member 500, and thus the movement of the coolant inside the cooling member 500 is limited, the amount of the coolant injected into the first battery cell 110a may be limited to the amount of the coolant received between the vulnerable portion 522 and the upper plate 510.

This can be applied even in the case where the cooling member 500 has a system connected to an external tank. Specifically, the control system including the cooling member 500 may detect thermal transition or thermal runaway, and when thermal runaway is detected, the amount of coolant supplied to the first battery cell 110a may be limited within the volume range of the cooling member 500 by controlling inflow or circulation of additional coolant.

As described above, the vulnerable part 522 according to the present embodiment injects coolant into the correct place at the correct time during the internal fire of the battery pack or the battery module, thereby enabling to quickly suppress a fire and prevent a continuous thermal runaway phenomenon.

The frangible portion 522 described in this embodiment can be formed in various ways.

For example, the vulnerable portion 522 may be formed by partially etching the lower plate 520. The frangible portion 522 can be formed using a grooving process. However, the apparatus used in the etching process may be difficult to control to a precise level, and when the thickness of the lower plate 520 is thin, or when the thickness of the desired vulnerable portion 522 is thin, the dimensional stability of the vulnerable portion 522 may be greatly reduced. For example, when the lower plate 520 is formed of aluminum, the lower plate 520 may have a thin thickness of 4mm, 3mm, or 2mm or less. The proper thickness of the vulnerable portion 522 may be changed according to the material of the vulnerable portion 522, but when the lower plate 520 is formed of aluminum, the vulnerable portion 522 may be preferably formed to a thickness of 0.2mm to 0.5 mm. In order to provide the vulnerable portion 522 on the lower plate 520, it is necessary to make the vulnerable portion 522 have a thin film-level thickness by removing a portion of the lower plate 520 that is already thin enough. When the control of the apparatus is not complete, the lower plate 520 may be damaged in the process of forming the vulnerable portion 522, thereby possibly wasting process costs and process time due to an increase in defective products. Therefore, when the lower plate 520 has the vulnerable portion 522 as in the present embodiment, it may be undesirable to apply an etching process.

In order to form the vulnerable portion 522 to have a sufficiently thin thickness, the lower plate 520 may be formed by bonding two layers. As shown in fig. 8, the lower plate 520 may be formed by combining a first layer 524 provided as a plate-shaped member and a second layer 526 having a plurality of holes. For reference, a portion indicated by oblique lines in fig. 8 represents the second layer 526, and a partially hollow space between oblique lines represents a cross section of a hole formed in the second layer 526. The holes formed in the second layer 526 may be portions for forming the frangible portions 522 described above. The aperture may have an elongated shape. One or more holes may be formed along a straight line parallel to the long sides of the lower plate 520. When a plurality of holes are provided along a straight line parallel to the long sides of the lower plate 520, the holes may not have an elongated shape according to the number and spacing of the holes. Further, the axial cross-section of the bore may have various shapes as shown in fig. 5. The radial cross-section of the hole may have an angular shape or may have a circular shape.

A portion of the lower plate 520 may have a relatively thick thickness by including the first layer and the second layer, and another portion of the lower plate 520 may have a relatively thin thickness by including only the first layer 524. Here, the portion having the first layer 524 may be referred to as a first portion, and the portion having both the first layer 524 and the second layer 526 may be referred to as a second portion. Thus, the thickness of the first portion may correspond to the thickness of the first layer 524 and the thickness of the second portion may correspond to the total thickness of the first layer 524 and the second layer 526.

When the lower plate 520 is formed by combining two layers, the thickness of each layer can be freely adjusted so that the vulnerable portion 522 can be formed to be thin enough. For example, if both the first layer 524 and the second layer 526 are provided by aluminum, the first layer 524 is provided as an aluminum plate having a thickness of 0.03 to 0.07mm, or 0.04 to 0.06mm, or 0.05mm, and the second layer 526 may be provided in the following state: holes are formed in an aluminum plate having a thickness of 1.0 to 1.5mm or more. Here, in the case of a design requiring mechanical rigidity, the thickness of the first layer 524 may be designed to be thick enough to be melted by thermal runaway of the battery cell. Thus, it is possible to provide the first layer 524 with a value slightly larger than the above thickness value. When the aluminum plate of the second layer 526 is bonded to one surface of the first layer 524 accordingly, a lower plate 520 having a frangible portion 522 of sufficiently thin thickness may be formed.

Here, when the lower plate 520 is formed by combining two layers, all the vulnerable portions 522 are formed as one plate, and thus, the thickness values may be equal to each other. When the first and second vulnerable portions are formed on the lower plate 520, the thicknesses of the first and second vulnerable portions may be substantially equal to each other. Further, here, the thickness value of each vulnerable portion 522 may not be deviated depending on the position. When a thickness deviation according to a position occurs in the vulnerable portion 522, a portion thereof may be formed thicker than designed, whereby a specific portion may be difficult to break due to heat or pressure. However, since the vulnerable portions 522 described in the present embodiment are all formed to have a uniform thickness, errors between design and actual products can be minimized.

Various types of bonding processes may be applied to bond the two layers forming the lower plate 520. Since the coolant is located on the upper surface of the lower plate 520, it is necessary to firmly form the coupling of the two layers.

For example, the coupling of the two layers may be formed by a welding process. Examples of welding processes for coupling may include brazing or laser welding. The two layers may be melt bonded by applying a temperature similar to the melting point of the material to the two layers. By fusion bonding, the water tightness of the lower plate 520 can reach a desired level.

In another example, the coupling of the two layers may be formed by a rolling process. The rolling process is a method of bonding two layers by passing a laminate in which two or more layers are laminated between a pair of rollers. The laminate may be heated during interlayer bonding by a rolling process, wherein if the heating temperature is higher than the recrystallization temperature of the metal, the process is called hot rolling, and if the heating temperature is lower than the above temperature, the process is called cold rolling. By applying pressure and/or heat to the laminate, a wide bonding surface can be formed between the two layers, and thus, the water tightness of the lower plate 520 can be sufficiently ensured.

Meanwhile, when the lower plate 520 is formed by coupling two layers, the materials of the two layers may be different, or may have the same or similar materials as each other. If the materials of the two layers are the same or similar to each other, the melting points of the two layers are the same/similar, and thus the above-described bonding process involving heat or pressure can be more easily performed.

Meanwhile, when two layers are bonded through a brazing process, the bonding process may not be smoothly performed according to the physical properties or melting point of the metal. For example, if the two layers are formed of aluminum of a single nature, setting the temperature of the brazing process to a level of 660 ℃ (this is the melting point of aluminum) may cause the shape of the aluminum layers to deform during the bonding process. To prevent such layer deformation, the first layer 524 or the second layer 526 may be made of clad metal, which is a double layer metal material.

For example, when the combination of layers is formed by a brazing process, the first layer 524 may be 3000 series aluminum and the second layer 526 may be a clad metal comprising 3000 series and 4000 series aluminum. Since the second layer 526 includes clad metal, the temperature of the brazing process may be set to a level of 600 deg.c, whereby the shape of aluminum may be prevented from being deformed during the bonding process.

The above-mentioned bonding method may be used even when the upper plate 510 and the lower plate 520 are coupled. Therefore, when the physical properties of the upper plate 510 and the lower plate 520 are the same, the joint between the two members can be more densely formed. For example, the upper and lower plates 510 and 520 or the first and second layers 524 and 526 may include aluminum.

Meanwhile, in the lower plate 520 provided with the vulnerable portion 522 as described above, a case where the lower surface of the lower plate 520 has a flat shape is mainly described. However, the stepped portion (i.e., the groove) of the lower plate 520 formed by locally adjusting the thickness may not face the inside of the cooling member 500 but may be exposed to the outside.

Fig. 9 is a view showing another example of the section A-A of fig. 3. Fig. 10 is a view illustrating another example of a cooling member provided in a battery cell stack according to an embodiment of the present disclosure. Fig. 11 is an enlarged view of the region C of fig. 10, which is a view for explaining a change in the lower plate when the battery cell catches fire. Fig. 12 is a cross-sectional view illustrating another example of a cooling member according to an embodiment of the present disclosure.

Referring to fig. 9 to 12, unlike the frangible portion 522 shown in fig. 5 to 8, which is formed to be located near the lower surface of the lower plate 520, the frangible portion 522 may be formed to be located near the upper surface of the lower plate 520. As shown in fig. 9 to 12, when the vulnerable portion 522 is positioned close to the upper surface of the lower plate 520, the lower surface of the cooling member 500 may have a partially protruding shape. Accordingly, the protruding lower surface of the cooling member 500 may be positioned close to the battery cell or may be in contact with the battery cell, thereby promoting heat dissipation of the battery cell.

As shown in fig. 9, the cross section of the lower plate 520 may have a square, triangular, circular or trapezoidal cross-sectional shape. Since the sectional shape of fig. 9 can be explained with reference to the content of fig. 5 except that the vertical direction is reversed, a detailed description thereof will be omitted.

Fig. 10 and 11 are views showing a cross section taken along the xz plane when the cooling member 500 is shown on the battery cell stack, the direction of which is different from the directions of fig. 6 and 7 described above, and thus, the cross section of the cooling member 500 is illustrated in more detail. In fig. 6 and 7, the positional relationship between the plurality of battery cells 110 and the vulnerable portion 522 is shown, and in fig. 10 and 11, the positional relationship between one battery cell 110 and the vulnerable portion 522 is shown. Referring to fig. 10 and 11, one battery cell 110 may correspond to a plurality of vulnerable parts 522, and the vulnerable parts 522 corresponding thereto may be opened according to the location in the battery cell 110 where the fire occurs. Accordingly, when the battery cell 110 catches fire, one vulnerable portion 522 may be opened, or a plurality of vulnerable portions 522 may be opened. Here, the opening of the vulnerable portion 522 includes a case where only a part of one vulnerable portion is opened, and does not necessarily mean that the entire vulnerable portion 522 is opened.

Fig. 10 and 11 are different not only in direction from fig. 6 and 7, but also show the following differences: the lower surface of the cooling member 500 has a protruding shape. Even though the lower surface of the cooling member 500 has a protruding shape, when the battery cell 110 catches fire, the vulnerable portion 522 is opened so that the injection of coolant into the battery cell 110 is identical, whereby the detailed description of fig. 10 and 11 can be described with reference to fig. 6 and 7. Therefore, in order to avoid repetitive description, detailed description will be omitted.

Meanwhile, the lower plate 520 having the protruding lower surface and the vulnerable portion 522 formed thereon may be formed in various ways. For example, the vulnerable portion 522 may be formed by etching the lower surface of the lower plate 520. In another example, the lower plate 520 may be formed by combining two layers.

Specifically, as shown in fig. 12, the lower plate 520 may be formed by combining a first layer 524 provided as a plate-shaped member and a second layer 526 having a plurality of holes. At this time, the second layer 526 may be positioned under the first layer 524, thereby forming the lower surface of the lower plate 520. Here, when the bonding portion between the second layer 526 and the first layer 524 is formed by a brazing process, the first layer 524 may include 3000 series and 4000 series clad metals, and the second layer 526 may include 3000 series aluminum. At this time, the upper plate 510 may be also 3000 series aluminum, and bonding between the layers may be smoothly performed by 4000 series aluminum formed on the upper and lower surfaces of the first layer 524 provided as a clad metal. Alternatively, the first layer 524 may be provided as a 3000 series aluminum and the second layer 526 or upper plate 510 may be provided as a 3000 series or 4000 series clad metal.

Other coupling methods of the lower plate 520 and detailed descriptions of the first and second layers 524 and 526 may be explained with reference to the description of fig. 8, and thus, detailed descriptions thereof will be omitted.

Next, a cooling member according to another embodiment of the present disclosure will be described.

Fig. 13 is a cross-sectional view illustrating a cooling member according to another embodiment of the present disclosure.

The cooling member 500 of the embodiment explained with reference to fig. 13 may include all of the above-described fig. 1 to 12, in addition to the following. Therefore, in order to minimize repetitive description, contents overlapping with the above-described contents will be omitted.

Referring to fig. 13, the cooling member 500 described in the present embodiment may have three layers. Specifically, the upper plate 510 of the cooling member 500 may have one layer, and the lower plate 520 may have two layers. Here, since the lower plate 520 having two layers has been fully explained through the above, a detailed description thereof will be omitted.

Since the coolant in the cooling member 500 is received between the upper plate 510 and the lower plate 520, the flow deviation of the coolant can be determined according to the separation distance between the upper plate 510 and the lower plate 520. In the above figures, the upper plate 510 of the cooling member 500 is shown as having a flat surface as a whole, except that the flow path forms the groove 550 and the deformation preventing groove 560. Accordingly, the flow deviation of the cooling member 500 may depend on the thickness difference of the lower plate 520. Specifically, the flow per unit length may be relatively large around the first portion where the frangible portion 522 is formed, while the flow per unit length may be relatively small around the second portion where the frangible portion 522 is not formed. If the flow around the first portion is large, coolant may be injected faster according to the hydraulic pressure when the frangible portion 522 is opened. Therefore, this may be more preferable when the flow around the first portion is larger.

Therefore, in the present embodiment, the upper plate 510 having the bent portion 514 may be provided to form a flow deviation of the coolant in the cooling member 500. The bent portion 514 may have a wave-shaped cross-sectional shape based on a cross-section in the longitudinal direction of the cooling member 500. Here, based on the cross section, the highest point (i.e., peak) of the bent portion 514 may correspond to a first portion of the lower plate 520 forming the vulnerable portion 522. Further, the lowest point (i.e., trough) of the bend 514 may correspond to the second portion of the lower plate 520. By making the peak of the bent portion 514 correspond to the first portion, the flow rate per unit length around the first portion can be increased, and when the vulnerable portion 522 is opened, the coolant of the cooling member 500 can be injected more rapidly toward the first battery cell 110a where the ignition phenomenon occurs.

In fig. 13, the valleys of the bends 514 are shown as being located adjacent to the second portion of the lower plate 520, but the valleys of the bends 514 may be spaced apart from the second portion of the lower plate 520 such that the cooling member 500 may contain a greater amount of coolant. However, if the spacing distance is too large, the total volume of the cooling member 500 may increase, which may be a factor in increasing the size of the battery module. Therefore, the cooling member 500 may have to be properly designed in consideration of the heat generated by the battery cells 110.

Further, in fig. 13, the layers of the cooling member 500 are shown as being positioned in the order of the first layer 524, the second layer 526, and the upper plate 510, but may be positioned in the order of the second layer 526, the first layer 524, and the upper plate 510. If the second layer 526 is positioned under the first layer 524, the lower surface of the cooling member 500 may have a protruding shape due to the second layer 526. Since the second layer 526 forming the lower surface of the cooling member 500 may be positioned close to the battery cell or may be in contact with the battery cell, if positioned in the order of the second layer 526, the first layer 524, and the upper plate 510, an effect of promoting heat dissipation of the battery cell through the second layer 526 may be exhibited.

Further, in the cooling member 500 provided in fig. 13, the thickness of each layer may be appropriately designed to have a strength greater than or equal to a predetermined range while minimizing the total volume. For example, in the cooling member 500 having three layers, the upper plate 510 may be referred to as a third layer, and may be made of aluminum. When the third layer is formed of aluminum, the upper plate 510 may be preferably formed to have a thickness of 1.0 to 2.0mm, 1.3 to 1.7mm, or 1.5 mm. Further, the second layer 526 included in the lower plate 520 may be preferably formed to have a thickness of 1.0 to 1.5mm, 1.2 to 1.4mm, or 1.3 mm. The first layer 524 may have to be formed thin enough to have the properties of the vulnerable portion 522, and in particular, the first layer 524 may have a thickness of 0.03 to 0.07mm or 0.04 to 0.06 mm.

Various processes may be applied to interlayer coupling in the cooling member 500 having three layers. Since the coolant is located in the cooling member 500, a combination of three layers needs to be firmly formed.

In one example, the coupling of the three layers may be formed by a welding process.

In another example, the coupling of the three layers may be formed by a rolling process. However, when a rolling process in which pressure is applied via rollers is employed, the formation of the upper plate 510 may be somewhat limited.

Meanwhile, when the lower plate 520 is formed by coupling three layers, materials of the three layers may be respectively different, or may be the same or similar to each other. Since the melting point or strength varies depending on the material, the material may have to be selected depending on the manufacturing method, or the manufacturing method may have to be selected depending on the material.

For example, in the structure shown in fig. 13, when the joint of the layers is formed by brazing, the first layer 524 may be 3000 series aluminum, the second layer 526 may be clad metal containing 3000 series or 4000 series aluminum, and the third layer as the upper plate 510 may be 3000 series aluminum.

In another example, the positions of the first layer 524 and the second layer 526 in the structure shown in fig. 13 may be interchanged. At this time, when the joint of the layers is formed by brazing, the materials of the second layer 526 and the upper plate 510 coupled with the first layer 524 are limited according to the physical properties of the first layer 524. In a specific example, the first layer 524 includes a 3000 series aluminum, and the second layer 526 and upper plate 510 may include a clad metal including a 3000 series/4000 series aluminum. In another specific example, the first layer 524 includes a 3000 series/4000 series clad metal, and the second layer 526 and upper plate 510 may include 3000 series aluminum.

Next, a battery pack including the cooling member described above will be described.

The battery pack 1000 of the embodiment described with reference to fig. 14 and 15 may include all of fig. 1 to 13, except as described below. Therefore, in order to minimize repetitive description, the above-mentioned matters related to the cooling member 500 will be omitted.

Fig. 14 is an exploded perspective view illustrating a battery pack according to an embodiment of the present disclosure. Fig. 15 is a perspective view of a battery module included in the battery pack according to fig. 14.

Referring to fig. 14, a battery pack 1000 according to an embodiment of the present disclosure may include: at least one battery module 100; a battery pack frame 200 for accommodating the battery modules 100; a resin layer 300 formed on the inner surface of the battery frame 200; end plates 400 closing the open surfaces of the battery frame 200; and a cooling member 500 disposed between the battery frame 200 and the battery cell stack 120. However, the components included in the battery pack 1000 are not limited thereto, and depending on the design, the battery pack 1000 may be provided in a state in which some of the above-mentioned components are omitted, and the battery pack 1000 may be provided in a state in which other components not mentioned are added.

Referring to fig. 14 and 15, the battery module 100 provided in the present embodiment may have a non-module structure in which a module frame is omitted.

Conventionally, a conventional battery pack has a double assembly structure in which a battery cell stack and a part of components connected thereto are assembled to form a battery module, and a plurality of battery modules are again received in the battery pack. At this time, since the battery module includes a module frame forming the outer surface thereof, the conventional battery cells are doubly protected by the module frame of the battery module and the battery pack frame of the battery pack. However, such a double assembly structure has disadvantages in that not only the manufacturing cost and the manufacturing process of the battery pack are increased, but also the re-assembly performance is deteriorated when defects occur in some battery cells. In addition, when a cooling member or the like exists outside the battery module, there is a problem in that a heat transfer path between the battery cells and the cooling member is somewhat complicated.

Accordingly, the battery module 100 of the present embodiment may be provided in the form of a "cell block" in which a module frame is omitted, and the battery cell stack 120 included in the cell block may be directly coupled to the battery pack frame 200 of the battery pack 1000. Thereby, the structure of the battery pack 1000 may be simplified, advantages in terms of manufacturing costs and manufacturing processes may be obtained, and weight saving of the battery pack may be achieved.

Hereinafter, the battery module 100 without a module frame may be referred to as a "cell block" to distinguish it from a battery module having a module frame. However, the battery module 100 is a general term having the battery cell stack 120 divided into predetermined units for modularization regardless of whether a module frame exists, and the battery module 100 should be construed to include both typical battery modules and cell blocks without a module frame.

Referring to fig. 15, the battery module 100 according to the present embodiment may include: a cell stack 120 in which a plurality of cells 110 are stacked in one direction; side surface plates 130 at both ends in the stacking direction of the battery cell stack 120; a holding band 140 wrapped around the side surface plates 130 and the battery cell stack 120 to fix the shape thereof; and a bus bar frame 150 for covering the front and rear surfaces of the battery cell stack 120.

Meanwhile, fig. 15 shows the battery modules 100 provided in the form of a single block, but the contents of these figures do not exclude the case where the battery modules 100 having the sealing structure of the module frame are applied to the battery pack 1000 of the present embodiment.

The battery cells 110 may include an electrode assembly, a unit case, and electrode leads protruding from the electrode assembly, respectively. The battery cells 110 may be provided in a pouch shape or a prismatic shape, wherein the number of stacked cells per unit area may be maximized. For example, the battery cell 110 provided in a pouch may be manufactured by accommodating an electrode assembly including a positive electrode, a negative electrode, and a separator in a single body case made of a laminate sheet, and then heat sealing the sealed portion of the single body case. Meanwhile, fig. 14 and 15 show that the positive electrode lead and the negative electrode lead of the battery cell 110 protrude in opposite directions to each other, but this is not necessarily the case, and the electrode leads of the battery cell 110 may protrude in the same direction.

The cell stack 120 may be a cell stack in which a plurality of electrically connected cells 110 are stacked in one direction. The direction in which the plurality of battery cells 110 are stacked (hereinafter referred to as a "stacking direction") may be a y-axis direction (or-y-axis direction) as shown in fig. 14 and 15, and hereinafter, the expression "axial direction" may be interpreted to include all +/-directions.

Meanwhile, since the battery cells 110 are disposed in one direction, electrode leads of the battery cells 110 may be located on one surface of the battery cell stack 120 or on one surface of the battery cell stack 120 and the other surface facing the one surface. In this way, the surface of the cell stack 120 where the electrode leads are located may be referred to as a front surface or a rear surface of the cell stack 120, and in fig. 14 and 15, the front surface and the rear surface of the cell stack 120 are shown as two surfaces opposite to each other in the x-axis.

Further, the surface of the cell stack 120, on which the outermost cell 110 is located, may be referred to as a side surface of the cell stack 120, and in fig. 14 and 15, the side surfaces of the cell stack 120 are shown as two surfaces opposite to each other on the y-axis.

The side surface plates 130 may be provided to maintain the overall shape of the cell stack 120. The side surface plates 130 are plate-shaped members and may replace a module frame to supplement the rigidity of the individual blocks. The side surface plates 130 may be disposed at both ends of the cell stack 120 in the stacking direction, and may be in contact with the outermost cells 110 on both sides of the cell stack 120.

The side surface plate 130 may be manufactured from various materials and may be provided by various manufacturing methods. In one example, the side surface plate 130 may be made of a plastic material manufactured by injection molding. In another example, the side surface plate 130 may be made of a plate spring material. In another example, the side surface plate 130 may be made of a material having elasticity such that its shape may be partially deformed in response to a volume change of the battery cell stack 120 due to swelling.

The holding strap 140 may be used to fix the positions and shapes of the side surface plates 130 at both ends of the battery cell stack 120. The holding strap 140 may be a member having a length and a width. In particular, the cell stack 120 may be located between two side surface plates 130 in contact with the outermost cells 110, and the holding strap 140 may span the cell stack 120 to connect the two side surface plates 130. Accordingly, the holding band 140 can prevent the distance between the two side surface plates 130 from increasing beyond a certain range, whereby the overall shape of the single block can be held within a certain range.

The holding strap 140 may have hooks at both ends in the longitudinal direction for stable coupling with the side surface plate 130. The hook portion may be formed by bending both ends of the holding band 140 in the longitudinal direction. Meanwhile, the side surface plate 130 may have a hook groove formed at a position corresponding to the hook, and the holding strap 140 and the side surface plate 130 may be stably coupled by coupling of the hook and the hook groove.

The retainer strap 140 may be provided from a variety of materials or by a variety of manufacturing methods. In one example, the holding strap 140 may be made of a material having elasticity, thereby allowing a volume change of the battery cell stack 120 due to swelling to a certain extent.

Meanwhile, the holding strap 140 serves to fix the relative position between the side surface plate 130 and the cell stack 120, and if the purpose of a "fixing member" is achieved, it may be provided in a shape other than that shown. For example, the fixing member may be provided in the form of a long bolt (i.e., a long bolt) capable of crossing between the two side surface plates 130. The side surface plates 130 may be provided with grooves into which long bolts may be inserted, and the long bolts may be coupled with both side surface plates 130 through the grooves at the same time, thereby fixing the relative positions of the two side surface plates 130. The long bolts may be provided at the edges of the side surface plates 130, preferably at positions near the vertices of the side surface plates 130. Depending on the design, the retaining strap 140 can be replaced with the long bolt mentioned above, but both the retaining strap 140 and the long bolt may also be provided in a single block.

The bus bar frame 150 may be used to cover one surface of the battery cell stack 120 and at the same time guide the connection between the battery cell stack 120 and an external device by being located on one surface of the battery cell stack 120. The bus bar frame 150 may be located on the front surface or the rear surface of the battery cell stack 120. Two bus bar frames 150 may be provided to be located on the front and rear surfaces of the battery cell stack 120. The bus bars may be mounted on the bus bar frame 150, and electrode leads of the battery cell stack 120 are connected to the bus bars through the bus bar frame 150, so that the battery cell stack 120 may be electrically connected to external devices.

The bus bar frame 150 may include an electrically insulating material. The bus bar frame 150 may limit contact of the bus bars with other portions of the battery cell 110 except for the portion coupled to the electrode leads, and may prevent electrical short circuit from occurring.

The battery pack frame 200 may serve to protect the battery module 100 and the electrical equipment connected thereto from external physical impacts. The battery pack frame 200 may accommodate the battery modules 100 and the electrical equipment connected thereto in the inner space of the battery pack frame 200. Here, the battery pack frame 200 includes an inner surface and an outer surface, and the inner space of the battery pack frame 200 may be defined by the inner surface.

The battery modules 100 received in the battery pack frame 200 may be formed in plurality. The plurality of battery modules 100 may be referred to as "module assemblies". The module assemblies may be arranged in rows and columns within the battery frame 200. Here, "row" may mean a group of battery modules 100 arranged in one direction, and "column" may mean a group of battery modules 100 arranged in a direction perpendicular to the one direction. For example, as shown in fig. 1, the battery modules 100 may be arranged along the stacking direction of the battery cell stacks to form one row or one column, thereby forming a module assembly.

The battery pack frame 200 may be provided in a hollow shape that is open in one direction. For example, as shown in fig. 1, a plurality of battery modules 100 are positioned one after another along the stacking direction of the battery cells 110, and the battery pack frame 200 may have a hollow shape that is open along the above-mentioned stacking direction.

The battery pack frame 200 may have various structures. In one example, as shown in fig. 1, the battery pack frame 200 may include a lower frame 210 and an upper frame 220. Here, the lower frame 210 may be provided in a plate shape, and the upper frame 220 may be provided in a U shape. At least one battery module 100 may be disposed in the plate-shaped lower frame 210, and the U-shaped upper frame 220 may be disposed to wrap both surfaces of the upper surface and the x-axis of the module assembly.

The battery pack frame 200 may include a portion having high thermal conductivity so as to rapidly dissipate heat generated in the inner space to the outside. For example, at least a portion of the battery frame 200 may be made of a metal having high thermal conductivity, and examples thereof may be aluminum, gold, silver, copper, platinum, an alloy containing these, or the like. Further, the battery pack frame 200 may have a partial electrical insulation property, and an insulation film may be provided at a location where insulation is required, or an insulation coating may be applied. The portion of the battery frame 200 to which the insulating film or the insulating coating is applied may be referred to as an insulating portion.

The resin layer 300 may be disposed between the battery module 100 and the inner surface of the battery frame 200. The resin layer 300 may be disposed between the bottom surface of the battery module 100 and the lower frame 210. The resin layer 300 may be disposed between the upper surface of the battery module 100 and the upper frame 220. Here, in particular, the resin layer 300 may be disposed between the cooling member 500 and the upper frame 220, which will be described later.

The resin layer 300 may be formed by injecting a resin between one of the inner surfaces of the battery cell stack 120 and the battery frame 200. However, this is not necessarily the case, and the resin layer 300 may be a member provided in a plate shape.

The resin layer 300 may be made of various materials, and the function of the resin layer 300 may vary according to materials. For example, the resin layer 300 may be formed of an insulating material, and electron transfer between the battery module 100 and the battery frame 200 may be prevented by the insulating resin layer 300. In another example, the resin layer 300 may be formed of a thermally conductive material. The resin layer 300, which is made of a heat conductive material, transfers heat generated in the battery cells 110 to the battery pack frame 200 so that the heat can be released/transferred to the outside. In other examples, the resin layer 300 may include an adhesive material by which the battery module 100 and the battery frame 200 may be fixed to each other. In a specific example, the resin layer 300 may be provided to include at least one of a silicone-based material, a polyurethane-based material, and an acrylic-based material.

The end plate 400 may serve to protect the battery module 100 and the electrical components connected thereto from external physical impact by sealing the open surface of the battery frame 200. Each edge of the end plate 400 may be coupled to a corresponding edge of the battery frame 200 by a method such as welding. The end plates 400 may be provided in two in order to seal the two open surfaces of the battery frame 200, and may be made of a metal material having a predetermined strength. An opening 410 may be formed in the end plate 400 to expose an inlet/outlet port 530 of the cooling member 500, which will be described later, and a connector 420 for Low Voltage (LV) connection or High Voltage (HV) connection with external devices may be installed.

The cooling member 500 may be used to cool the inside of the battery pack 1000 by radiating heat generated from the battery cells 110. For the description of the cooling member 500, reference is made to the above.

Meanwhile, the cooling member 500 is shown in fig. 14 as being disposed at the outside of the battery module 100, but this is not necessarily the case, and the cooling member 500 may be disposed at the inside of the battery module 100. At this time, the battery module 100 may have a closed structure having a module frame or an open structure such as a unit block.

Further, in the above-mentioned drawings, the cooling member 500 is shown to have a separate structure, but the cooling member 500 may be integrally provided with the battery pack 1000 or the battery module 100. For example, when the cooling member 500 is integrally provided with the battery pack 1000, the upper plate 510 of the cooling member 500 is replaced with the upper surface of the battery pack frame 200, and the upper surface of the battery pack frame 200 and the lower plate 520 of the cooling member 500 are coupled, so that the cooling member 500 can be formed. In another example, when the cooling member 500 is integrally provided with the battery module 100, the upper plate 510 of the cooling member 500 is replaced with the upper surface of the frame of the battery module 100, and the upper surface of the frame of the battery module 100 and the lower plate 520 of the cooling member 500 are coupled, so that the cooling member 500 can be formed. When the cooling member 500 is integrated with the battery pack 1000 or the battery module 100, effects such as weight saving, cost reduction, and simplification of the internal structure of the battery pack 1000 or the battery module 100 can be achieved by omitting some members.

Further, the battery module 100 according to the present embodiment has been described as including the water-cooling type cooling member 500, but the description does not exclude the case where the battery module 100 may include the air-cooling type cooling member. Therefore, it should be noted that the battery module 100 described in the present embodiment may include both the air-cooled type and the water-cooled type cooling member 500.

Fig. 16 is a perspective view illustrating a cooling member according to another embodiment of the present disclosure. Fig. 17 is a perspective view illustrating a cooling member according to an embodiment of the present disclosure. Fig. 18 is a top view of a lower plate included in the cooling member shown in fig. 16. Fig. 19 is a top view of a body included in the cooling member shown in fig. 16. Fig. 20 is a view showing a coupled state of a lower plate, a main body, and a cooling hose included in the cooling member shown in fig. 16. Fig. 21 is a view showing the cooling member of fig. 17 taken along line A-A, showing the flow of coolant into and out of the main body and the cooling hose. Fig. 22 is a sectional view taken along the line A-A of the cooling member shown in fig. 17, illustrating injection of a coolant through the cooling hose when the battery cell catches fire.

Referring to fig. 16 and 17, the cooling member 600 described in the present embodiment may be provided to reduce the internal temperature of a battery module or a battery pack including battery cells. The cooling member 600 may be a water-cooled cooling member 600 into which a refrigerant or coolant is injected. By providing the cooling member 600 in a water-cooling manner, the cooling efficiency of the cooling member 600 can be uniformly maintained, and the battery cells within the battery module or the battery pack can be uniformly cooled. The coolant used in the cooling member 500 may use one of known coolants or a mixture thereof, and if the heat of the battery cells can be dissipated by moving along the flow path inside the cooling member 600, any of the known coolants may be used.

The cooling member 600 may be disposed on one surface of the battery cell stack to emit heat of the battery cells. The cooling member 600 may be arranged in parallel with the stacking direction of the battery cell stack so as to be positioned close to the plurality of battery cells of the battery cell stack. In particular, the cooling member 600 may be located on the upper portion of the battery cell stack.

The size of the cooling member 600 may be matched to the size of the battery cell stack to which the cooling member 600 is applied. In one example, the cooling member 600 may be disposed to correspond to one cell stack, wherein the length of the cooling member 600 may be matched to the length of the cell stack, or may be formed to be larger or smaller with little margin, and the width of the cooling member 600 may be matched to the width of the cell stack, or may be formed to be larger or smaller with little margin. In another example, the cooling member 600 may be disposed to correspond to a plurality of battery cell stacks, wherein the length and width of the cooling member 600 may be matched to those of the plurality of battery cell stacks, or may be formed to be larger or smaller with little margin. Here, the cooling member 600 may be located inside the battery module, but it may also be located at the inside of the battery pack from the outside of the battery module.

The cooling member 600 may include: a lower plate 620; an inlet/outlet port 630 injecting a coolant into the interior of the cooling member 600; a main body 640 and a cooling hose 650 installed on an upper surface of the lower plate 620 and accommodating a coolant; and a fixing member 660 for fixing the same. Referring to fig. 20, the main body 640 is mounted on the upper surface of the lower plate 620, the cooling hose 650 is mounted on the receiving part 648 of the main body 640, and the fixing member 660 fixes the lower plate 620, the main body 640, and the cooling hose 650, so that the cooling member 600 can be manufactured.

The cooling member 600 according to the present embodiment can ensure water tightness and simplify the manufacturing process by the above-mentioned structure, and can supply the coolant to the correct place at the correct time when the battery cells catch fire.

When a fire occurs in the battery cells, it may be effective to inject a liquid such as a coolant into the battery module or the battery pack in order to effectively suppress the fire. Having a liquid tank within the battery module or the battery pack may have the problem of increasing the volume of the battery module and the battery pack. Therefore, conventionally, separate water tanks are provided outside the battery module and the battery pack, and only when the ignition of the battery cells is confirmed by the sensor, a coolant or the like is injected into the battery module or the battery pack through a nozzle or the like extending from the water tank.

However, the water tanks provided outside the battery module and the battery pack have a problem in that the volume thereof is large, and the user must also manage them separately. Furthermore, the conventional water injection system must be equipped with a separate control unit or communication unit for determining whether to inject the coolant, must cause errors in its operation, and must undergo many determination processes even if it is normally operated, which requires a lot of time. Even after deciding to inject the coolant, if the path from the water tank to the battery cells inside the battery module or the battery pack is somewhat long, it is difficult to rapidly supply the coolant from the water tank to the battery cells, and thus, it is difficult to suppress the continuous thermal runaway phenomenon that the conventional water injection system rapidly performs. Accordingly, in the present embodiment, when a fire occurs inside the battery module or the battery pack, an opening may be formed in the lower plate 620 of the cooling member 600, and the cooling hose 650 may be arranged to correspond to the opening, so that the coolant may be immediately supplied to the fire scene.

In order to achieve an effect similar to the above, an opening is formed in the lower surface of a conventional cooling member, and then the opening may be closed by filling or inserting a member that melts or breaks at a predetermined temperature or pressure or higher. However, in the conventional structure in which the coolant of the cooling member 600 directly contacts the lower plate 620, the coolant may leak through a gap between the opening of the lower plate 620 and the member sealing it, and thus, the water tightness of the cooling member 600 may be greatly reduced. In addition, since manufacturing the lower plate 620 to include two materials having different physical properties involves a complicated manufacturing process, there is a problem in that manufacturing time and manufacturing cost are increased. Accordingly, in the cooling member 600 of the present embodiment, by isolating the coolant between the main body 640 and the cooling hose 650, deterioration of water tightness due to the opening 622 of the lower plate 620 can be minimized. In addition, by applying the main body 640 and the cooling hose 650 to the cooling member 600, a manufacturing process of the cooling member 600 may be simplified, and manufacturing time and cost may be reduced.

Referring to fig. 18, the lower plate 620 may be provided in a plate shape. A main body 640 through which a coolant flows and a cooling hose 650 may be installed on the lower plate 620. The lower plate 620 may be preferably provided in a plate shape to support the main body 640, etc.

The lower plate 620 may include at least one opening 622. The openings 622 may be used to inject an internal coolant into the battery cells by heat or pressure generated due to the ignition during the internal ignition of the battery cells. The opening 622 may be provided in plurality along a straight line parallel to the short side or the long side of the lower plate 620, and the cooling member 600 has a plurality of openings 622 such that coolant may be injected in response to a fire occurring at an unspecified location in the battery module or the battery pack. In this connection, reference is made to fig. 22 described later.

A protrusion 624 extending from one side of the lower plate 620 and successively positioned along one edge of the lower plate 620 may be formed around the lower plate 620. The protrusions 624 may be disposed to contact or be adjacent to electrode leads of each cell stack or bus bars connected to the electrode leads. Since the electrode leads or the bus bars, which provide electrical connection in the battery module or the battery pack, are constructed to be easily heated, if the above-mentioned protrusions promote heat dissipation of the electrode leads or the bus bars, it is possible to more effectively prevent the temperature rise of the battery cells.

A small shelf 626 may be formed on the lower plate 620. The small shelf 626 may extend from the center in the width direction of the cooling member 600 along the longitudinal direction of the cooling member 600 except for a predetermined region. The main body 640 may be installed in a fixed position by the small shelf 626, and the fixing member 660 may be stably fixed. Here, the width direction of the cooling member 600 may be a direction parallel to the short side of the cooling member 600. Further, here, the longitudinal direction of the cooling member 600 may be a direction parallel to the long side of the cooling member 600.

The lower plate 620 may be a portion of the cooling member 600 that is positioned closest to the battery cells. The lower plate 620 may be provided with a material having high thermal conductivity to promote heat dissipation of the battery cells. The lower plate 620 of the cooling member 600 may be made of a metal having high rigidity, and specific examples thereof include aluminum, gold, silver, copper, platinum, or an alloy containing these.

Coolant may be supplied through inlet ports 632 positioned side-by-side and discharged to outlet ports 634. The inlet port 632 and the outlet port 634 may be located side by side in parallel on one end side of the cooling member 600. This may be used to simplify the design regarding inflow and discharge of coolant supplied from the outside of the battery module or the battery pack. In addition, this may be used to minimize the temperature differential between the perimeter of the inlet port 632 and the perimeter of the outlet port 634. Specifically, the coolant flowing into the inlet port 632 may have the lowest temperature and the coolant discharged to the outlet port 634 may have the highest temperature. Accordingly, when the inlet/outlet ports 630 are disposed adjacent to each other, mutual heat exchange occurs, so that temperature deviation of the entire coolant flowing through the inner space of the cooling member can be minimized. Accordingly, by arranging the inlet/outlet ports 630 side by side, the cooling member 600 may have uniform heat dissipation performance as a whole.

Referring to fig. 19 to 21, the main body 640 may provide a coolant flow path for heat dissipation of the battery cells. Coolant injected through the inlet port 632 may be contained inside the body 640, and coolant contained in the main body 640 may be discharged through the outlet port 634. As coolant flows into or out of the body 640, the cooling member 600 may be maintained at a relatively constant temperature. The coolant in the main body 640 may be designed to be continuously circulated by being connected to an external heat exchanger connected to the inlet/outlet port 630 so as to keep its temperature constant.

The lower plate 620 cooled by the main body 640 may facilitate heat dissipation of the battery cells. The main body 640 may be made of a material having high thermal conductivity, which can rapidly absorb heat of the lower plate 620. The body 640 may be made of a material that is sufficiently rigid to withstand the pressure and weight of the coolant contained therein. The main body 640 may be made of the same or similar material as that of the lower plate 620. The material of the body 640 may include, for example, aluminum, gold, silver, copper, platinum, or alloys containing these.

The main body 640 may be installed in the lower plate 620 at a position where the small shelf 626 is not formed. The outer shape of the main body 640 may be similar to the outer shape of the lower plate 620, except for the protrusions 624.

The main body 640 may have a square tube shape, and the inlet port 632 and the outlet port 634 may be branched into two portions corresponding to each other in consideration of the position of the small shelf 626. Thus, the body 640 may form a U-shaped flow path. The body 640 may include: a first portion 642 extending from the inlet port 632 along a line parallel to the longitudinal direction of the cooling member 600; a second portion 644 extending along a curve rotating in a clockwise or counterclockwise direction at a distal end of the first portion 642; and a third portion 646 extending toward the outlet port 634 along a line parallel to the longitudinal direction of the cooling member 600 at a distal end of the second portion 644. Here, the longitudinal direction of the cooling member 600 may be a direction parallel to the long side of the cooling member 600.

The main body 640 may include a receiving part 648, and the cooling hose 650 is mounted to the receiving part 648. The accommodating part 648 may mean an accommodating space in which the cooling hose 650 is installed in the main body 640. The receiving part 648 may be a long groove extending in the longitudinal direction of the cooling member 600, and the receiving part 648 may be polygonal or circular in cross section such as square. Both ends of the cooling hose 650 in the longitudinal direction may be connected to both ends of the receiving part 648 in the longitudinal direction. Both ends of the cooling hose 650 may be inserted into both ends of the receiving part 648 in the longitudinal direction. The connection portions between the both ends of the receiving part 648 in the longitudinal direction and the both ends of the cooling hose 650 may be sealed to ensure water tightness. For example, a gasket is provided at a connection portion between the cooling hose 650 and the receiving part 648, and water tightness between the two members may be ensured by the gasket.

In another example, both end portions of the cooling hose 650 may be formed with an extension portion extending from the end portion of the cooling hose 650 in the circumferential direction, and an expansion portion is inserted into the distal end portion of the receiving portion 648 and located inside the main body 640, so that the coupling between the cooling hose 650 and the main body 640 may be supplemented. In another example, a first extension extending in the circumferential direction and a second extension spaced apart from the first extension may be formed at a distal end portion of the cooling hose 650. The first extension may be located on an interior of the main body 640 and the second extension may be located on an exterior of the main body 640. The coupling between the cooling hose 650 and the main body 640 can be further supplemented by the close contact of the two extensions with the main body 640. Further, at this time, a protrusion may be formed on the extension (the first extension or the second extension), and the extension may be more closely coupled with one side of the body 640 via the protrusion.

The cooling hose 650 may be connected to the main body 640 to provide a flow path of a coolant that achieves heat dissipation of the battery cells. Coolant flowing in from the inlet/outlet port 630 may move to the cooling hose 650. The cooling hose 650 may be supplied with coolant from the main body 640 positioned adjacent to the inlet/outlet port 630.

The cooling hose 650 may be positioned to correspond to the opening 622 of the lower plate 620. As shown in fig. 18, when 4 rows of openings 622 are formed in the lower plate 620 along a straight line parallel to the longitudinal direction of the cooling member 600, 4 cooling hoses 650 may be provided to correspond to each row of openings 622. Here, "row" may collectively denote openings 622 that are positioned one after the other along a straight line parallel to the longitudinal direction of the cooling member 600.

Referring to fig. 22, the cooling hose 650 may be melted or broken when an internal fire occurs, thereby injecting an internal coolant toward the battery cells. When a battery cell fires, a portion of the cooling hose 650 corresponding to the opening 622 is opened by melting or breaking, whereby the fire in the battery cell located below the cooling member 600 can be suppressed by spraying, jetting, and flowing coolant in the direction of gravity. Meanwhile, in order to achieve this effect, the receiving part 648 to which the cooling hose 650 is mounted should also be formed to correspond to the opening 622 of the lower plate 620.

The cooling hose 650 may be made of a material that is more easily melted by heat or broken by pressure than the lower plate 620 made of metal. For example, the cooling hose 650 may be made of a material having a melting point of 300 ℃ or less. In a specific example, the cooling hose 650 may be manufactured to include Polyamide (PA). In another specific example, the cooling hose 650 may be manufactured to include a thermoplastic polymer resin having a melting point of 200 ℃ or less. Examples of the thermoplastic polymer resin include materials having melting points of about 100 ℃ or more and 200 ℃ or less, such as High Density Polyethylene (HDPE), polyethylene (PE), polypropylene (PP), or polyphenylene oxide (PPO).

Meanwhile, in order to achieve the above-mentioned effect, without separately manufacturing the cooling hose 650, the following configuration may be adopted: a portion of the body 640 breaks to allow injection of coolant. However, in order for the main body 640 to withstand the pressure of the coolant flowing therein and maintain its shape, since the main body 640 must be made of a material having sufficient rigidity, it has a problem in that it is made of a material that is easily melted by heat or broken by pressure: the overall durability of the cooling member 600 may be deteriorated. Therefore, as in the present embodiment, it may be preferable to construct a cooling hose 650, which may be easily broken by heat, separately from the main body 640 for improving the performance of the entire cooling member 650.

The fixing member 660 may serve to supplement the rigidity of the cooling member 600 by fixing the lower plate 620, the main body 640, and the cooling hose 650. The fixing member 660 may fix the positions of the main body 640 and the cooling hose 650 by being coupled with the lower plate 620.

The fixing member 660 may be provided in a belt shape having a certain length. The fixing member 660 may be positioned in parallel with the width direction of the cooling member 600. The fixing members 660 may be provided in plurality along the longitudinal direction of the cooling member 600, and the plurality of fixing members 660 may be arranged at uniform intervals.

The fixing member 660 may be made of a material having high rigidity so as to maintain the shape of the cooling member 600, and may be made of metal as an example.

The fixing member 660 may be coupled to both ends in the width direction of the cooling member 600. The fixing member 660 may be coupled to the center of the cooling member 600 in the width direction. The fixing member 660 may include: end coupling portions 662 each formed at both ends of the fixing member 660 in the longitudinal direction; and a central coupling portion 664 formed at the center in the longitudinal direction of the fixing member 660. The end coupling part 662 and the central coupling part 664 may refer to portions fastened in the cooling member 600 by fastening members such as rivets. Fasteners may be formed in the end coupling portions 662 and the central coupling portion 664, into which the fastening members may be inserted.

The fixing members 660 may be coupled to both ends of the lower plate 620 in the width direction. The fixing member 660 may be coupled to the center of the lower plate 620 in the width direction. The end coupling parts 662 may be coupled to the protrusions 624 at both ends of the lower plate 620 in the width direction. The central coupling portion 664 may be coupled to a small shelf 626 located at the center in the width direction of the lower plate 620. The end coupling part 662 and the central coupling part 664 may be formed to have a step difference from other portions of the fixing member 660 so as to have a height slightly lower than the other portions of the fixing member 660. The end coupling part 662 may be formed to have a larger step difference than the central coupling part 664 in consideration of the shapes of the protrusion 624 and the small shelf 626.

When the fixing member 660 is used in the manufacture of the cooling member 600 in this way, excessive heat is not generated during the manufacturing process, as compared to the coupling method by the welding process, and some temperature sensitive materials may not be deformed during the manufacture. Accordingly, by using the fixing member 660, the cooling member 600 may be manufactured to include two or more materials having different properties, and various materials and shapes of structures may be applied to the cooling member 600, such as the cooling hose 650, and the design of the cooling member 600 may be easier and more versatile.

Next, a method of manufacturing a cooling member according to another embodiment of the present disclosure will be described. The manufacturing method of the cooling member 600 described below includes all the matters related to the cooling member 600 described above, and thus a detailed description of overlapping matters is omitted.

Referring back to fig. 20, a method of manufacturing a cooling member according to another embodiment of the present disclosure may include: a step of preparing a lower plate 620; a step of mounting a main body 640 on an upper surface of the lower plate 620; a step of mounting a cooling hose 650 to the main body 640; and a step of coupling the fixing member 660 with the lower plate 620.

According to this embodiment, the step of preparing the lower plate 620 may include the step of forming an opening 622 in the lower plate 620, and may further include the step of mounting an inlet/outlet port 630 to the lower plate 620.

The step of mounting the main body 640 to the lower plate 620 is a process of bonding the lower plate 620 and the main body 640, and may be performed through a bonding process such as welding. When the lower plate 620 and the main body 640 are combined using a welding process, since materials of the lower plate 620 and the main body 640 are more similar, deformation or damage of some components according to a welding temperature can be minimized, and dimensional safety of the cooling member 600 can be ensured.

The step of mounting the cooling hose 650 to the main body 640 may include: a step of inserting a cooling hose 650 into the accommodating part 648 of the main body 640; and a step of connecting both ends of the cooling hose 650 with both ends of the receiving part 648. Here, the connection portion between the cooling hose 650 and the receiving part 648 may be sealed.

The step of coupling the fixing member 660 with the lower plate 620 may include: a step of coupling end coupling portions 662 of the fixing member 660 with both ends of the lower plate 620; and a step of coupling the central coupling portion 664 of the fixing member 660 with the center of the lower plate 620. Here, both ends of the lower plate 620 mean ends in the width direction, and the protrusions 624 may be located at both ends of the lower plate 620. Further, the center of the lower plate 620 means the center in the width direction, and a small shelf 626 may be located at the center of the lower plate 620.

Meanwhile, although not specifically mentioned above, the cooling fin 600 according to still another embodiment of the present disclosure may be mounted in a battery module or a battery pack.

A battery module according to still another embodiment of the present disclosure includes a battery cell stack made of a plurality of battery cells and a module frame for accommodating the battery cell stack, and a cooling member 600 may be disposed between the module frame and the battery cell stack.

The battery pack according to still another embodiment of the present disclosure may be provided in various forms.

In one example, a battery pack according to an embodiment of the present disclosure may include at least one or more of the above-described battery modules. The battery pack of the present embodiment may include a battery pack frame and at least one battery module mounted in the battery pack frame, wherein the battery module includes a battery cell stack, a module frame, and a cooling member between the battery cell stack and the module frame.

In another example, a battery pack according to still another embodiment of the present disclosure may include: at least one battery module including a battery cell stack and a module frame for accommodating the battery cell stack; and a cooling member 600 and a battery pack frame for accommodating the battery module and the cooling member 600. That is, in this example, the cooling member 600 may be disposed at the outside of the battery module. The cooling member 600 may be disposed between a module frame and a battery pack frame of the battery module, and when the inside or outside of the battery module catches fire, a coolant may be injected toward the battery module.

In another example, a battery pack according to another embodiment of the present disclosure may include a battery cell stack and a battery pack frame for accommodating the battery cell stack, and a cooling member 600 may be disposed between the battery cell stack and the battery pack frame.

Here, the battery cell stack may be provided in a non-module structure that is not sealed by a module frame or the like. The cell stack may be provided in an open structure. At this time, the battery cell stack may be provided in a state in which the outer shape thereof is maintained by a fixing member such as a side surface plate or a holding belt, and this type of battery cell stack may be called a cell block.

Typically, the battery pack may be formed in a double assembly structure in which battery modules are formed by assembling a battery cell stack and several parts connected thereto, and a plurality of battery modules are again received in the battery pack. At this time, since the battery module includes a module frame forming the outer surface thereof, the conventional battery cells are doubly protected by the module frame of the battery module and the battery pack frame of the battery pack. However, such a double assembly structure not only increases the manufacturing unit cost and the manufacturing process of the battery pack, but also has the disadvantage of deteriorated reassembly when some battery cells are defective. Further, when a cooling member or the like is present outside the battery module, there is a problem in that: the heat transfer path between the battery cells and the cooling member is somewhat complicated. Accordingly, the battery cell stack of the present embodiment may be provided in a structure that is not sealed by the module frame, and may be directly coupled to the battery pack frame of the battery pack. Thereby, the structure of the battery pack becomes simpler, advantages in terms of manufacturing costs and manufacturing processes can be obtained, and weight saving of the battery pack can be achieved. Further, the battery cell stack herein is provided in a non-module structure, whereby the battery cell stack may be positioned closer to the cooling member 600 in the battery pack frame, and heat dissipation of the cooling member 600 may be more easily accomplished.

For a description of a case in which the cooling member 600 according to another embodiment of the present disclosure is mounted in a battery module or a battery pack, reference may be made to the description related to fig. 14 and 15, and thus a detailed description of overlapping contents is omitted.

Further, according to the present disclosure, the cooling member 500 described above in fig. 1 to 15 and the cooling member 600 described above in fig. 16 to 22, respectively, are not limited, and even when they are combined, various modifications and variations may be made, for example, by equally or partially modifying and applying the cooling member 500 described above in fig. 1 to 15 to the main body 640 of the cooling member 600 described above in fig. 16 to 22.

Meanwhile, although not specifically mentioned above, the battery pack according to the embodiments of the present disclosure may include a Battery Management System (BMS) that manages the temperature or voltage of the battery and/or a cooling device.

The battery pack according to the embodiments of the present disclosure may be applied to various devices. The apparatus to which the battery pack is applied may be a vehicle device such as an electric bicycle, an electric vehicle, or a hybrid vehicle. However, the above-mentioned devices are not limited thereto, and the battery pack according to the present embodiment may be used for various devices other than the above-described illustrations, which also falls within the scope of the present disclosure.

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

Description of the reference numerals

100 Battery Module

110 battery cell

120 cell stack

130 side surface plate

140 holding strap

150 bus bar frame

200 Battery pack frame

300 resin layer

400 end plate

500 Cooling Member

510 upper plate

514 bending portion

520 lower plate

522 vulnerable portion

530 inlet/outlet ports

540 sealing portion

550 flow path forming grooves

560 deformation preventing groove

600 Cooling Member

620 lower plate

630 inlet/outlet ports

640 main body

650 cooling hose

660 fixing member

Claims

1. A cooling member located in an upper portion of a battery cell stack in which a plurality of battery cells are stacked, the cooling member comprising:

an upper plate, a lower plate, and a coolant contained in an inner space between the upper plate and the lower plate,

wherein the lower plate comprises a first part and a second part, wherein the first part is provided with a vulnerable part, the second part is not provided with the vulnerable part, and

Wherein the thickness value of the first portion is smaller than the thickness value of the second portion.

2. The cooling member of claim 1, wherein:

the vulnerable part has a long side and a short side, and

the long sides extend along the stacking direction of the battery cells.

3. The cooling member of claim 1, wherein:

the thickness value of the first portion is less than or equal to half the thickness value of the second portion.

4. The cooling member of claim 1, wherein:

the thickness of the first portion is 0.03 to 0.07mm.

5. The cooling member of claim 1, wherein:

the frangible portion includes a first frangible portion and a second frangible portion spaced apart from the first frangible portion, and

the thickness values of the first and second frangible portions are substantially the same.

6. The cooling member of claim 1, wherein:

the lower plate is formed by bonding a first layer and a second layer having different thicknesses from each other,

the thickness of the first portion corresponds to the thickness of the first layer, and

the thickness of the second portion corresponds to the thickness of the first layer and the second layer.

7. The cooling member of claim 6, wherein:

One of the first layer and the second layer includes a cladding metal.

8. The cooling member of claim 6, wherein:

9. The cooling member of claim 6, wherein:

the first layer and the second layer are joined by a brazing process.

10. The cooling member of claim 6, wherein:

the upper plate, the first layer and the second layer are joined by a brazing process.

11. The cooling member of claim 1, wherein:

the upper plate includes a curved portion that,

the crest of the bending part corresponds to the first part, and

the valleys of the bends correspond to the second portions.

12. A cooling member located at an upper portion of a battery cell stack in which a plurality of battery cells are stacked, the cooling member comprising:

a lower plate, a plurality of openings are formed at the lower plate,

a body providing a flow path for a coolant, and

a fixing member to which the lower plate and the main body are fixed,

wherein at least one cooling hose is mounted on the body, and

Wherein the cooling hose melts or breaks at a predetermined temperature or pressure or higher.

13. The cooling member of claim 12, wherein:

the cooling hose is positioned to correspond to the opening of the lower plate.

14. The cooling member of claim 12, wherein:

the cooling hose has a shape extending along a longitudinal direction of the cooling member.

15. The cooling member of claim 12, wherein:

the cooling hose is made of a material having a melting point of 300 ℃ or less.

16. The cooling member of claim 12, wherein:

the main body is provided with a receiving portion for receiving the cooling hose.

17. The cooling member of claim 16, wherein:

both ends in the longitudinal direction of the cooling hose are connected to both ends in the longitudinal direction of the accommodating portion, respectively.

18. The cooling member of claim 12, wherein:

a small shelf extending in the longitudinal direction of the cooling member is formed at the center of the lower plate, and the main body is mounted on the lower plate at a position where the small shelf is not formed.

19. The cooling member of claim 12, wherein:

the fixing member is provided in a belt shape and is positioned in parallel with a width direction of the cooling member.

20. The cooling member of claim 19, wherein:

the fixing member includes end coupling portions coupled with both ends in a width direction of the lower plate and a center coupling portion coupled with a center in the width direction of the lower plate.

21. The cooling member of claim 20, wherein:

the end coupling portion and the central coupling portion are formed to have a step difference from other portions of the fixing member.

22. The cooling member of claim 12, wherein:

the cooling member further comprises an inlet port and an outlet port for injecting a coolant into the interior space,

wherein the inlet port and the outlet port are connected to an external heat exchanger, an

Wherein the coolant of the cooling member circulates through the inlet port and the outlet port.

23. The cooling member of claim 22, wherein:

the body has a branched shape corresponding to the inlet port and the outlet port.

24. A battery module comprising the cooling member according to claim 1 or 12.

25. The battery module of claim 24, wherein:

the upper plate of the cooling member is integrated with an upper surface of a module frame forming an external shape of the battery module.

26. A battery pack comprising the cooling member according to claim 1 or 12.

27. The battery pack of claim 26, wherein:

the battery pack includes battery modules having an open structure.

28. The battery pack of claim 26, wherein:

the upper plate of the cooling member is integrated with an upper surface of a battery pack frame forming an external shape of the battery pack.