One]Cross-Citation with Related Application(s)
[2]
This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0075829 dated June 25, 2019, and all contents disclosed in the literature of the Korean patent application are incorporated as a part of this specification.
[3]
The present invention relates to a battery pack and a device including the same, and more particularly, to a battery pack including one or more battery modules and a device including the same.
background
[4]
In modern society, as portable devices such as mobile phones, laptops, camcorders, and digital cameras are used daily, the development of technologies related to the mobile devices as described above is being actively developed. In addition, a rechargeable battery capable of charging and discharging is a method to solve air pollution such as conventional gasoline vehicles using fossil fuels, and electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles ( P-HEV) is being used as a power source, and the need for the development of secondary batteries is increasing.
[5]
Currently commercialized secondary batteries include nickel cadmium batteries, nickel hydride batteries, nickel zinc batteries, and lithium secondary batteries. Among them, lithium secondary batteries do not have much memory effect compared to nickel-based secondary batteries, so charging and discharging are possible freely. , the self-discharge rate is very low and the energy density is high.
[6]
These lithium secondary batteries mainly use a lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material, respectively. A lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate to which the positive electrode active material and the negative electrode active material are applied, respectively, are disposed with a separator interposed therebetween, and a casing for sealing and housing the electrode assembly together with an electrolyte, that is, a battery case.
[7]
In general, a lithium secondary battery may be classified into a can-type secondary battery in which an electrode assembly is embedded in a metal can and a pouch-type secondary battery in which an electrode assembly is embedded in a pouch of an aluminum laminate sheet, depending on the shape of the exterior material.
[8]
In the case of secondary batteries used in small devices, 2-3 battery cells are disposed, but in the case of secondary batteries used in mid- to large-sized devices such as automobiles, a battery module in which a plurality of battery cells are electrically connected this is used In such a battery module, a plurality of battery cells are connected in series or parallel to each other to form a cell stack, thereby improving capacity and output. In addition, one or more battery modules may be mounted together with various control and protection systems such as a battery management system (BMS) and a cooling system to form a battery pack.
[9]
In the case of a secondary battery, when the temperature is higher than an appropriate temperature, the performance of the secondary battery may be deteriorated, and in severe cases, there is a risk of explosion or ignition. In particular, a plurality of secondary batteries, ie, a battery module or battery pack having battery cells, may have a higher temperature more rapidly and severely because heat emitted from the plurality of battery cells is added up in a narrow space. In other words, in the case of a battery module in which a plurality of battery cells are stacked and a battery pack equipped with such a battery module, high output can be obtained, but it is not easy to remove heat generated from the battery cells during charging and discharging. If the heat dissipation of the battery cell is not performed properly, the deterioration of the battery cell is accelerated and the lifespan is shortened, and the possibility of explosion or ignition increases.
[10]
Moreover, in the case of a battery module included in a vehicle battery pack, it may be frequently exposed to direct sunlight and may be subjected to high temperature conditions such as summer or desert areas.
[11]
Therefore, when configuring the battery module or battery pack, it can be said that it is very important to secure a stable and effective cooling performance. Accordingly, a thermal pad or a heat sink is used as a cooling means of the battery pack to dissipate heat generated from the battery cell to the outside, but the battery cell and battery module, the battery module and the battery pack, etc. Due to the complex structure leading to , there is a factor that interferes with cooling performance, such as an air gap, so there is a problem in that effective cooling is difficult.
[12]
In addition, since other demands such as miniaturization, securing rigidity, and increasing capacity are continuing for the battery pack, it is practically necessary to develop a battery module that can satisfy these various requirements while improving cooling performance.
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[13]
Embodiments of the present invention have been proposed to solve the above problems, and an object of the present invention is to provide a battery pack having increased capacity and output as well as cooling performance and a device including the same.
[14]
However, the problems to be solved by the embodiments of the present invention are not limited to the above problems and may be variously expanded within the scope of the technical idea included in the present invention.
means of solving the problem
[15]
A battery pack according to an embodiment of the present invention includes: a battery module including a cell stack in which one or more battery cells are stacked, and a module frame for accommodating the cell stack; a pack frame for accommodating the battery module; and a thermally conductive resin layer positioned between the lower surface of the module frame and the pack frame, wherein an open portion is formed on the lower surface of the module frame, so that the cell stack is in contact with the thermally conductive resin layer.
[16]
The thermally conductive resin layer may include a thermally conductive adhesive material.
[17]
The thermally conductive resin layer may have a form in which the thermally conductive resin is solidified while in contact with the cell laminate.
[18]
The battery pack may further include a radiator positioned between the thermally conductive resin layer and the bottom of the pack frame.
[19]
At least one of the module frames may be a U-shaped frame, and the opening may be formed on a lower surface of the U-shaped frame.
[20]
A cover may be positioned on an upper surface of the U-shaped frame, and the U-shaped frame and the cover may be welded to each other to form a coupling portion.
[21]
At least one of the module frames may be a mono frame having an open front and back, and the opening may be formed on a lower surface of the mono frame.
[22]
The battery module may be two or more.
[23]
The pack frame may include barrier ribs formed between side surfaces of the battery modules.
[24]
Side surfaces of the battery modules may be in close contact with the partition wall.
[25]
The battery modules arranged along the side direction of the battery module, the side surfaces may be in close contact with each other.
[26]
The one or more battery cells may be stacked upright or inverted so as to be parallel to both sides of the module frame, and each of the one or more battery cells may be in contact with the thermally conductive resin layer.
[27]
The opening may be spaced apart from each of the front and rear surfaces of the module frame.
[28]
The opening may be adjacent to both sides of the module frame.
Effects of the Invention
[29]
According to embodiments of the present invention, it is possible to provide a battery pack having improved cooling performance by reducing a factor that interferes with cooling through the exposed structure of the battery cells formed in the module frame of the battery module.
[30]
In addition, since there is no need to dually dispose the heat transfer member inside the battery pack, it is possible to reduce the cost, and it is possible to reduce the quality inspection for the same, thereby simplifying the process and reducing the process cost.
[31]
In addition, by reducing the volume of the battery pack, it is advantageous for miniaturization, and the capacity or output of the battery pack can be increased even with the same size.
Brief description of the drawing
[32]
1 is a perspective view of a battery pack according to an embodiment of the present invention.
[33]
FIG. 2 is a cross-sectional view taken along line A-A' of FIG. 1 .
[34]
3 is an exploded perspective view of a battery module including a U-shaped frame.
[35]
4 is an exploded perspective view of a battery module including a mono frame.
[36]
5 is a perspective view of the battery module of FIG. 3 .
[37]
6 is a cross-sectional view for explaining a battery pack according to another embodiment of the present invention.
Modes for carrying out the invention
[38]
Hereinafter, with reference to the accompanying drawings, various embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily carry out the present invention. The present invention may be embodied in several different forms and is not limited to the embodiments described herein.
[39]
In order to clearly explain the present invention, parts irrelevant to the description are omitted, and the same reference numerals are assigned to the same or similar elements throughout the specification.
[40]
In addition, since the size and thickness of each component shown in the drawings are arbitrarily indicated for convenience of description, the present invention is not necessarily limited to the illustrated bar. In order to clearly express various layers and regions in the drawings, the thicknesses are enlarged. And in the drawings, for convenience of description, the thickness of some layers and regions are exaggerated.
[41]
Also, when a part of a layer, film, region, plate, etc. is said to be “on” or “on” another part, this includes not only cases where it is “directly on” another part, but also cases where there is another part in between. . Conversely, when we say that a part is "just above" another part, we mean that there is no other part in the middle. In addition, to be "on" or "on" the reference part means to be located above or below the reference part, and to necessarily mean to be located "on" or "on" in the direction opposite to gravity no.
[42]
In addition, throughout the specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated.
[43]
1 is a perspective view of a battery pack 100 according to an embodiment of the present invention.
[44]
Referring to FIG. 1 , a battery pack 100 according to an embodiment of the present invention includes a battery module 200 and a pack frame 400 accommodating the battery module 200 . Although six battery modules 200 are accommodated in FIG. 1 , the number is not limited, and one or more battery modules 200 may be accommodated in the pack frame 400 as necessary.
[45]
FIG. 2 is a cross-sectional view taken along line A-A' of FIG. 1 .
[46]
Referring to FIG. 2 , the battery module 200 includes a cell stack 300 in which one or more battery cells 310 are stacked and a module frame 210 accommodating the cell stack 300 . The thermal conductive resin layer 500 is positioned between the lower surface of the module frame 210 and the pack frame 400 , and an open part 240 is formed on the lower surface of the module frame 210 to form the cell stack 300 . It may be in contact with the thermally conductive resin layer 500 . Also, a heat sink 600 may be positioned between the thermal conductive resin layer 500 and the bottom of the pack frame 400 .
[47]
Hereinafter, the opening 240 formed on the lower surface of the module frame 210 will be described together with FIGS. 3 and 4 . 3 and 4 are exploded perspective views of battery modules 200a and 200b that can be applied to embodiments of the present invention. Specifically, FIG. 3 is an exploded perspective view of the battery module 200a including the U-shaped frame 210a, and FIG. 4 is an exploded perspective view of the battery module 200b including the mono frame 210b. In addition, both of FIGS. 3 and 4 show a state in which the lower surfaces of the battery modules 200a and 200b are turned upside down to see the top for convenience of explanation.
[48]
The module frame 210 of FIG. 2 is a metal plate, and a U-shaped frame or a mono frame may be applied. The battery module 200a of FIG. 3 is a U-shaped frame applied, and the battery module 200b of FIG. 4 is a mono frame. frame is applied.
[49]
Referring to FIG. 3 , the battery module 200a of this embodiment may include a U-shaped frame 210a for accommodating the cell stack 300 . The U-shaped frame 210a has an open top, front, and back surfaces, a cover 230 may be coupled to the open top surface, and an end plate 220 may be coupled to the open front and back surfaces.
[50]
At this time, as mentioned above, the opening 240a is formed on the lower surface of the U-shaped frame 210a so that the cell stack 300 is exposed through the opening 240a.
[51]
Referring to FIG. 4 , the battery module 200b of this embodiment may include a mono frame 210b for accommodating the cell stack 300 . The mono frame 210b has an open front and rear surface, and an end plate 220 may be coupled to the open front and rear surfaces.
[52]
Similarly, an opening 240b is formed on the lower surface of the mono frame 210b so that the cell stack 300 is exposed through the opening 240b.
[53]
2 to 4 again, through the openings 240, 240a, 240b formed on the lower surface of the module frame 210, that is, the U-shaped frame 210a or the mono frame 210b, the cell stack 300 ) is in contact with the thermally conductive resin layer 500 . Heat generated in the battery cells 310 of the cell stack 300 may be transferred through the thermally conductive resin layer 500 and the radiator 600 positioned under the thermally conductive resin layer 500 .
[54]
If the openings 240, 240a, and 240b are not formed, a heat transfer member such as the thermally conductive resin layer 500 is disposed between the cell stack 300 and the module frame 210 and between the module frame 210 and the radiator ( 600) has no choice but to be placed double between them. This is because it is necessary to remove all air gaps between the battery cell and the battery module and between the battery module and the battery pack for heat transfer.
[55]
However, in the present embodiment, since the open portions 240 , 240a and 240b are formed, there is no need to double dispose the thermally conductive resin layer 500 . Accordingly, it is possible to reduce the cost, and it is possible to reduce the quality inspection on the interface of the heat transfer member to one, thereby simplifying the process and reducing the process cost.
[56]
In addition, the height of the battery pack 100 may be reduced compared to a case in which the thermally conductive resin layer is double disposed. In general, when the battery pack is located on the floor of a vehicle, there is a large restriction on the height direction, but the battery pack 100 according to the present embodiment has an advantage in that the height restriction can be reduced.
[57]
From another point of view, in a limited space, since the volume of the battery cell 310 may increase as the number of thermally conductive resin layers decreases, the capacity and output of the battery pack 100 may be improved.
[58]
In addition, if the openings 240 , 240a and 240b are not formed, a double heat transfer member is positioned between the cell stack 300 and the radiator 600 , and a module frame is positioned between the dual heat transfer members Therefore, it is difficult to effectively transfer the heat generated from the battery cell 310 . This is because the module frame itself may deteriorate the heat conduction characteristics, and a fine air layer that may be formed between the module frame and the dual heat transfer members may also be a factor for lowering the heat conduction characteristics. In contrast, the openings 240 , 240a , and 240b in this embodiment can simplify the heat transfer path between the cell stack 300 and the radiator 600 into a single thermally conductive resin layer 500 . Therefore, it is possible to increase the cooling performance of the battery pack 100 .
[59]
Even when there is no configuration of the radiator 600 and the thermally conductive resin layer 500 is in direct contact with the bottom of the pack frame 400 , this principle can be applied similarly.
[60]
5 is a perspective view of the battery module 200a of FIG. 3 . However, unlike FIG. 3 , it is in a combined state, and is not turned over and the upper surface is viewed upward.
[61]
Referring to FIG. 5 together with FIG. 3 , the cover 230 may be coupled to the open upper surface of the U-shaped frame 210a, and the cover 230 may have a single plate-shaped structure. The U-shaped frame 210a and the cover 230 may form a structure surrounding the cell stack 300 by being coupled by welding or the like in a state in which corresponding corner portions are in contact with each other. That is, the U-shaped frame 210a and the cover 230 may be formed with a coupling portion CP formed by a coupling method such as welding at the corresponding corner portions.
[62]
Meanwhile, referring again to FIGS. 2 to 4 , the thermally conductive resin layer 500 in the present embodiment may include a thermally conductive resin, in particular, a thermally conductive adhesive material. For example, it may include at least one of a silicone-based material, a urethane-based material, and an acrylic-based material, and in particular, it is preferable to include a urethane-based material.
[63]
Since the thermally conductive resin layer 500 includes a thermally conductive resin having excellent thermal conductivity, the amount of heat transfer and the heat transfer rate between the cell laminate 300 and the radiator 600 may be further increased.
[64]
In addition, the thermally conductive resin includes a thermally conductive adhesive material, which is liquid when applied, but solidifies after the cell laminate 300 is laminated thereon through the openings 240 , 240a , 240b can be Accordingly, the thermally conductive resin layer 500 may fix the cell stack 300 and the battery modules 200 , 200a , and 200b including the same in the battery pack 100 . That is, the thermally conductive resin layer 500 in this embodiment not only improves the heat dissipation characteristics for the cell stack 300 through the openings 240 , 240a and 240b but also effectively fixes the cell stack 300 . has the effect of
[65]
For the above fixing, the thermally conductive resin layer 500 preferably has a peel strength of 400 g/cm or more when a peel test is performed. In addition, when performing a shear strength test (Shear strength test), it is preferable to have an adhesive strength of 1.4Mpa or more.
[66]
Referring back to FIG. 1 , in order to fix the battery module 200 in the pack frame 400 , a fastening structure such as hooks or bolts may be formed at four corners (black arrows) of the battery module 200 . This is to secure safety against vibration or shock when the battery module 200 is applied to a device to be described later.
[67]
However, in this embodiment, since the battery module 200 can be fixed in the battery pack 100 through the thermally conductive resin layer 500 in FIG. 2 , a fastening structure such as a hook structure or a bolt is applied to the battery module 200 ) can be located in only two or one of the four corners (black arrows), and in some cases, it is also possible to fix the battery module 200 only with the thermal conductive resin layer 500 without the fastening structure.
[68]
Meanwhile, referring back to FIGS. 1 and 2 , the pack frame 400 may further include a partition wall 410 formed between side surfaces of the battery modules 200 . The barrier rib 410 can support the battery pack 100 from external shocks, etc. when the battery pack 100 is applied to a device such as a vehicle, and also includes the battery modules 200 in the battery pack 100 . flow can be prevented. In addition, the side surfaces of the battery modules 200 may be in close contact with the partition wall 410 or may be spaced apart from each other at a predetermined interval. It may be more desirable to form a coherent structure.
[69]
Meanwhile, FIG. 6 is a cross-sectional view for explaining the battery pack 100a according to another embodiment of the present invention. Referring to FIG. 6 , the battery pack 100a may include a pack frame 400a without partition walls to form a structure in which side surfaces of the battery modules 200 are in close contact with each other. That is, the battery modules 200 arranged along the side direction among the battery modules may have a structure in close contact with each other through the side surface.
[70]
Configurations other than the same or similar to those of the battery pack 100 of FIGS. 1 and 2 are applied, so that the cell stack 300 of the battery module 200 is open formed on the lower surface of the module frame 210 . It is bonded to the thermal conductive resin layer 500a through the part 240 , and a radiator 600a may be positioned under the thermal conductive resin layer 500a. However, since the pack frame 400a does not include a partition wall, as shown in FIG. 6 , the battery modules 200 in close contact along the side surface may share one thermally conductive resin layer 500a.
[71]
As mentioned above, since the thermally conductive resin layers 500 and 500a of FIGS. 2 and 6 can fix the cell stack 300 or the battery modules 200, 200a, 200b, a separate bolt such as a bolt for fixing Fastening members can be reduced or eliminated. Therefore, instead of the space required for bolts or nuts to be fastened, the battery modules 200 form a structure in close contact with the partition wall 410 as shown in FIG. 2 or the battery modules 200 in close contact with each other as shown in FIG. can be formed Accordingly, since the battery module 200 can be arranged compactly, it can lead to a reduction in the volume of the battery packs 100 and 100a or an increase in battery capacity.
[72]
Referring back to FIG. 2 , it is preferable that the battery cells 310 constituting the cell stack 300 are stacked in an upright or inverted form so as to be parallel to both sides of the module frame 210 . Through this, each of the battery cells 310 may be exposed through the opening 240 to contact the thermally conductive resin layer 500 .
[73]
Also, referring back to FIGS. 3 and 4 , the openings 240a and 240b may be spaced apart from the front and rear surfaces of the module frames 210a and 210b, respectively. That is, on the lower surface of the module frames 210a and 210b, portions in which the openings 240a and 240b are not formed may be adjacent to the front and rear surfaces of the module frames 210a and 210b, respectively. If the openings 240a and 240b are formed in all areas of the lower surface, in the manufacturing process of the battery modules 200a and 200b or the assembly process of the battery pack, the problem of the cell stack 300 or a part thereof is separated there may be Considering the stacked shape and direction of the battery cells 310 described above, the openings 240a and 240b are formed while being spaced apart from the front and rear surfaces of the module frames 210a and 210b, respectively, so that the cell stack 300 is formed. ) can be prevented from escaping.
[74]
On the other hand, the openings (240a, 240b) may be adjacent to both sides of the module frame (210a, 210b). Considering the above-mentioned stacking shape and direction of the battery cells 310 , the openings 240a and 240b should be adjacent to both sides of the module frames 210a and 210b, so that both ends of the cell stack 300 . This is because all battery cells, including the battery cells constituting the , can contact the thermally conductive resin layer. Effective heat dissipation is possible only when all of the battery cells constituting the cell stack 300 are in contact with the thermally conductive resin layer.
[75]
The battery pack described above may be applied to various devices. Such a device may be applied to transportation means such as an electric bicycle, an electric vehicle, or a hybrid, but is not limited thereto, and may be applied to various devices that may use a secondary battery.
[76]
Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims are also provided. is within the scope of the
[77]
Explanation of symbols
[78]
100: battery pack
[79]
200, 200a, 200b: battery module
[80]
210: module frame
[81]
300: cell stack
[82]
400: pack frame
[83]
500: thermally conductive resin layer
[84]
600: radiator

WE CLAIMS

A battery module comprising a cell stack in which one or more battery cells are stacked and a module frame for accommodating the cell stack; a pack frame for accommodating the battery module; and a thermally conductive resin layer positioned between the lower surface of the module frame and the pack frame, wherein an open portion is formed on the lower surface of the module frame so that the cell stack is in contact with the thermally conductive resin layer.
[Claim 2]
The battery pack of claim 1 , wherein the thermally conductive resin layer includes a thermally conductive adhesive material.
[Claim 3]
The battery pack of claim 1 , wherein the thermally conductive resin layer has a form in which the thermally conductive resin is solidified while in contact with the cell stack.
[Claim 4]
The battery pack of claim 1 , further comprising a radiator positioned between the thermally conductive resin layer and a bottom of the pack frame.
[Claim 5]
The battery pack of claim 1 , wherein at least one of the module frames is a U-shaped frame, and the opening portion is formed on a lower surface of the U-shaped frame.
[Claim 6]
The battery pack of claim 5 , wherein a cover is positioned on an upper surface of the U-shaped frame, and the U-shaped frame and the cover are welded to each other to form a coupling portion.
[Claim 7]
The battery pack of claim 1 , wherein at least one of the module frames is a mono frame having an open front and back, and the opening is formed on a lower surface of the mono frame.
[Claim 8]
The battery pack of claim 1 , wherein the battery module includes two or more battery packs.
[Claim 9]
The battery pack of claim 8 , wherein the pack frame includes a partition wall formed between side surfaces of the battery modules.
[Claim 10]
The battery pack of claim 9, wherein side surfaces of the battery modules are in close contact with the partition wall.
[Claim 11]
The battery pack of claim 8 , wherein the battery modules disposed along the side direction of the battery module are in close contact with each other.
[Claim 12]
The battery pack of claim 1 , wherein the one or more battery cells are stacked in an upright or inverted form so as to be parallel to both sides of the module frame, and each of the one or more battery cells is in contact with the thermal conductive resin layer.
[Claim 13]
The battery pack of claim 1, wherein the opening portion is spaced apart from each of the front and rear surfaces of the module frame.
[Claim 14]
The battery pack of claim 1 , wherein the opening part is adjacent to both sides of the module frame.
[Claim 15]
A device comprising at least one battery pack according to claim 1 .