One]Cross-Citation with Related Application(s)
[2]This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0072499 on June 18, 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 module and a battery pack including the same, and more particularly, to a battery module that improves space utilization and a battery pack including the same.
background
[4]
Secondary batteries that are easy to apply according to product groups and have electrical characteristics such as high energy density are universally applied to electric vehicles or hybrid vehicles driven by an electric drive source, as well as portable devices, and power storage devices. These secondary batteries are attracting attention as a new energy source for improving eco-friendliness and energy efficiency in that not only the primary advantage of being able to dramatically reduce the use of fossil fuels but also the fact that no by-products are generated from the use of energy.
[5]
While one or two or three battery cells are used per device in small mobile devices, medium and large devices such as automobiles require high output and high capacity. Accordingly, a medium or large-sized battery module in which a plurality of battery cells are electrically connected is used.
[6]
Since it is desirable to manufacture the mid- to large-sized battery module as small as possible in size and weight, a prismatic battery, a pouch-type battery, etc. that can be stacked with a high degree of integration and have a small weight to capacity are mainly used as battery cells of the mid- to large-sized battery module. On the other hand, the battery module, in order to protect the cell stack from external impact, heat, or vibration, the front and rear are opened may include a frame member for accommodating the battery cell stack in the internal space.
[7]
1 is a perspective view showing a battery module having a conventional mono frame.
[8]
Referring to FIG. 1 , the battery module includes a battery cell stack 12 formed by stacking a plurality of battery cells 11 , a mono frame 20 with front and rear surfaces open to cover the battery cell stack 12 , The end covering the front and rear surfaces of the cover plate 40 covering the upper surface of the battery cell stack 12 , the bus bar frame 30 covering the front and rear surfaces of the battery cell stack 12 , and the mono frame 20 . A plate 60 may be included. Two bus bar frames 30 corresponding to each other may be connected by a cover plate 40 . A temperature sensor 50 is attached to the cover plate 40 .
[9]
In order to form such a battery module, horizontal assembly is required so that the battery cell stack 12 is inserted into the open front or rear surface of the mono frame 20 along the X-axis direction as shown by the arrow shown in FIG. 1 . However, it is necessary to ensure sufficient tolerance between the battery cell stack 12 and the mono frame 20 so that such horizontal assembly can be stably. Here, the tolerance refers to a gap generated by fitting or the like. In addition, a flexible circuit board 15 for electrically connecting the bus bar frames 30 at both ends is formed between the cover plate 40 and the battery cell stack 12, and the cover plate 40 is horizontally assembled. It is possible to prevent the flexible circuit board 15 from being damaged.
[10]
However, due to the cover plate 40 provided with the flexible circuit board 15 , the height of the battery module may also increase by the thickness thereof, and the weight of the battery module may increase.
[11]
As such, when the size of the battery module is increased, when the battery pack including the battery module is disposed under the vehicle, driving performance and fuel efficiency of the vehicle may be affected.
[12]
In addition, the height of the mono frame 20 should be designed to be large in consideration of the maximum height of the battery cell stack 12 and the assembly tolerance in the insertion process, which may result in wasted space unnecessarily.
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[13]
The problem to be solved by the present invention is to improve the space utilization rate by modifying the structure of the frame member surrounding the battery cell stack, and to maximize the advantages of the new structure, the sensing connection member and the new temperature sensor having a more compact and simple structure An object of the present invention is to provide a battery module having a sensor attachment method and a battery pack 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 module according to an embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, a U-shaped frame accommodating the battery cell stack and an open upper portion, and the battery in an upper portion of the open U-shaped frame. An upper plate covering the cell stack, a bus bar frame formed at both ends of the battery cell stack, and a bus bar frame positioned between the upper plate and the battery cell stack, respectively, connecting the bus bar frames formed at both ends of the battery cell stack a signal connection unit, and a bridge adjacent to the signal connection unit and hinged to the bus bar frame, to which a temperature sensor is attached.
[16]
The bridge may have a rotation axis.
[17]
The battery module may further include a compression pad positioned between the bridge and the battery cell stack.
[18]
The battery module may further include a double-sided tape positioned between the compression pad and the battery cell stack.
[19]
The temperature sensor may be a thermistor element.
[20]
A surface of the battery cell stack perpendicular to the stacking direction of the plurality of battery cells may be mounted on the bottom of the U-shaped frame.
[21]
It further includes an end plate coupled to each of the open both sides of the U-shaped frame, the open both sides of the U-shaped frame may face each other based on the direction in which the electrode leads of the battery cell stack protrude.
[22]
The U-shaped frame may include a bottom portion and two side portions facing each other while being connected by the bottom portion, and a distance between the two side portions may be equal to the width of the upper plate.
[23]
The signal connection part may be formed of a flexible flat cable (FFC) to connect bus bar frames at both ends of the battery cell stack.
[24]
A battery pack according to another embodiment of the present invention includes the battery module described above.
Effects of the Invention
[25]
According to embodiments, it is possible to improve the space utilization rate by implementing a U-shaped frame by reducing the tolerance between the battery cell stack and the frame compared to the prior art.
[26]
In addition, in order to maximize the advantage of the U-shaped frame structure, it is possible to minimize assembly interference by removing the cover plate and attaching the temperature sensor to the temperature sensor bridge, and to fix the temperature sensor at a certain position .
Brief description of the drawing
[27]
1 is an exploded perspective view showing a battery module having a conventional mono frame.
[28]
2 is an exploded perspective view illustrating a battery module according to an embodiment of the present invention.
[29]
3 is a perspective view illustrating a pouch-type battery according to an embodiment of the present invention.
[30]
FIG. 4 is a view showing a state in which a signal connection part and a bridge are coupled to a bus bar frame in the battery module of FIG. 2 .
[31]
FIG. 5 is an enlarged view of part P of FIG. 4 .
[32]
6 is a side view of FIG. 5 viewed from one side.
[33]
FIG. 7 is an enlarged view of part Q of FIG. 1 .
[34]
FIG. 8 is a partial view schematically showing the inside of part Q of FIG. 1 .
[35]
9 is a cross-sectional view taken along the cutting line I-I' of FIG. 7 .
Modes for carrying out the invention
[36]
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.
[37]
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.
[38]
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 is exaggerated.
[39]
Further, when a part of a layer, film, region, plate, etc. is said to be “on” or “on” another part, it includes not only cases where it is “directly on” another part, but also cases where another part is 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 the gravitational force not.
[40]
In addition, throughout the specification, when a part "includes" a certain component, this means that other components may be further included, rather than excluding other components, unless otherwise stated.
[41]
In addition, throughout the specification, when referring to "planar", it means when the target part is viewed from above, and "in cross-section" means when viewed from the side when a cross-section of the target part is vertically cut.
[42]
2 is an exploded perspective view illustrating a battery module according to an embodiment of the present invention. 3 is a perspective view illustrating a pouch-type battery according to an embodiment of the present invention.
[43]
Referring to FIG. 2 , the battery module 100 according to the present embodiment includes a battery cell stack 120 including a plurality of battery cells 110 , and a U-shaped frame 210 in which the upper surface, the front surface, and the rear surface are open. , the upper plate 220 covering the upper portion of the battery cell stack 120, the end plates 311 and 312 respectively positioned on the front and rear surfaces of the battery cell stack 120, and the battery cell stack 120 and the end and busbar frames 310 and 320 positioned between the plates 311 and 312 .
[44]
When the open both sides of the U-shaped frame 210 are referred to as the first side and the second side, respectively, the U-shaped frame 210 is the battery cell stack 120 corresponding to the first side and the second side. Among the remaining outer surfaces except for the surface, the plate-shaped structure is bent so as to continuously cover the adjacent front surface, the upper surface, and the rear surface.
[45]
The upper plate 220 is a plate-shaped structure surrounding the remaining lower surfaces except for the front, upper and rear surfaces covered by the U-shaped frame 210 among the remaining outer surfaces except for the front and rear surfaces of the battery cell stack 120 . consist of. The U-shaped frame 210 includes a bottom portion 300a and two side portions 300b facing each other. The U-shaped frame 210 and the upper plate 220 may form a structure surrounding the battery cell stack 120 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 210 and the upper plate 220 may be coupled to the corresponding corner portions by welding or the like.
[46]
The battery cell stack 120 includes a plurality of battery cells 110 stacked in one direction, and the plurality of battery cells 110 may be stacked in the Y-axis direction as shown in FIG. 2 . The battery cell 110 is preferably a pouch-type battery cell. For example, referring to FIG. 3 , in the battery cell 110 according to this embodiment, two electrode leads 111 and 112 face each other, so that one end 114a and the other end 114b of the battery body 113 are opposite to each other. ) has a structure protruding from each other. The battery cell 110 is manufactured by adhering both ends 114a and 114b of the battery case 114 and one side 114c connecting them to the battery case 114 in a state in which an electrode assembly (not shown) is accommodated. can be In other words, the battery cell 110 according to this embodiment has a total of three sealing portions 114sa, 114sb, 114sc, and the sealing portions 114sa, 114sb, 114sc are sealed by a method such as thermal fusion. , the other one side may be formed of a connection part 115 . Between both ends 114a and 114b of the battery case 114 is defined in the longitudinal direction of the battery cell 110 , and one side portion 114c and a connecting portion connecting both ends 114a and 114b of the battery case 114 . A space between 115 may be defined in the width direction of the battery cell 110 .
[47]
The connection part 115 is an area extending along one edge of the battery cell 110 , and a protrusion 110p of the battery cell 110 may be formed at an end of the connection part 115 . The protrusion 110p may be formed on at least one of both ends of the connecting unit 115 and may protrude in a direction perpendicular to the extending direction of the connecting unit 115 . The protrusion 110p may be positioned between one of the sealing parts 114sa and 114sb of both ends 114a and 114b of the battery case 114 and the connection part 115 .
[48]
The battery case 114 generally has a laminate structure of a resin layer/metal thin film layer/resin layer. For example, when the battery case surface is made of an O (oriented)-nylon layer, when stacking a plurality of battery cells to form a medium or large-sized battery module, it tends to slide easily due to an external impact. Therefore, in order to prevent this and maintain a stable laminated structure of the battery cells, an adhesive member such as an adhesive such as a double-sided tape or a chemical adhesive bonded by a chemical reaction during adhesion is attached to the surface of the battery case to form a battery cell laminate. (120) can be formed. In this embodiment, the battery cell stack 120 is stacked in the Y-axis direction, is accommodated in the U-shaped frame 300 in the Z-axis direction, and the bottom of the battery cell stack 120 and the U-shaped frame 300 . Cooling may be performed by the thermally conductive resin layer (not shown) formed between the 210a. As a comparative example to this, there is a case where the battery cells are formed of cartridge-shaped parts, and the fixing between the battery cells is made by assembling the battery module frame. In this comparative example, there is little or no cooling action due to the presence of the cartridge-shaped part, or it may proceed in the direction of the surface of the battery cell, and the cooling is not well in the direction of the height of the battery module.
[49]
Before the battery cell stack 120 according to this embodiment is mounted on the bottom portion 300a of the U-shaped frame 300, a thermal conductive resin is applied to the bottom portion 210a of the U-shaped frame 210, The thermally conductive resin may be cured to form a thermally conductive resin layer.
[50]
Thereafter, the battery cell stack 120 may be mounted on the bottom portion 210a of the U-shaped frame 210 while moving in a direction perpendicular to the bottom portion 210a of the U-shaped frame 210 . At this time, the thermally conductive resin layer is positioned between the bottom portion 210a of the U-shaped frame 210 and the battery cell stack 120 . The thermally conductive resin layer may serve to transfer heat generated in the battery cell 110 to the bottom of the battery module 100 and to fix the battery cell stack 120 .
[51]
The width of the side portion 210b and the upper plate 220 of the U-shaped frame 210 according to the present embodiment may be the same as each other. In other words, the edge portion along the X-axis direction of the upper plate 220 and the edge portion along the X-axis direction of the side portion 210b of the U-shaped frame 210 may directly meet and be coupled by a method such as welding.
[52]
The battery module 100 according to the present embodiment is located adjacent to the signal connection unit 400 and the signal connection unit 400 connecting the bus bar frames 310 and 320 formed at both ends of the battery cell stack 120 , respectively. It includes a bridge 500 that does. The bridge 500 is hinged to the bus bar frame 320 , and a temperature sensor 450 is attached thereto. The signal connection unit 400 may be formed of a flexible flat cable (FFC).
[53]
Conventionally, a flexible printed circuit (FPC) is provided between busbar frames, and the two busbar frames are connected through the flexible circuit board, and the upper end of the flexible printed circuit board is covered to prevent damage to the flexible printed circuit board. An additional plate was installed. The cover plate was a component added separately from the upper plate 220 and the corresponding plate according to the present embodiment. However, according to an embodiment of the present invention, the cover plate protecting and supporting the flexible circuit board is removed, and a flexible flat cable (FFC) that does not require a protection member such as a cover plate is used instead of the flexible circuit board. The two bus bar frames 310 and 320 are connected. Since it has a method and structure for covering the battery cell stack 120 by the combination of the U-shaped frame 210 and the upper plate 220, even if a flexible flat cable is used without an existing cover plate, damage can be prevented.
[54]
Through the connection of the two busbar frames through the FFC in this way, the height of the battery module 100 can be reduced to increase the energy density of the battery module itself.
[55]
As described above, the signal connection unit 400 formed of FFC according to an embodiment of the present invention is positioned between the upper plate 220 and the battery cell stack 120 . In more detail, an insulating member (not shown) is formed on the upper surface of the battery cell stack 120 , and the signal connection unit 400 may be positioned between the insulating member (not shown) and the upper plate 220 . .
[56]
The signal connection unit 400 is formed of a soft cable and can be bent, and since the circuit for electrical connection between the bus bar frames is inserted in the cable, it is easy to cope with an external shock.
[57]
Hereinafter, a temperature sensor according to an embodiment of the present invention will be described with reference to FIGS. 4 to 6 .
[58]
FIG. 4 is a view showing a state in which a connection signal unit and a bridge are coupled to a bus bar frame in the battery module of FIG. 2 . FIG. 5 is an enlarged view of part P of FIG. 4 . 6 is a side view of FIG. 5 viewed from one side.
[59]
4 and 5 , the temperature sensor 450 according to the present embodiment is attached to the bridge 500 . As the bridge 495 rotates with the rotation shaft 495 , the temperature sensor 450 may also rotate. The temperature sensor 450 according to the present embodiment may be formed of a thermistor element. The thermistor element is a semiconductor element using a phenomenon in which a resistance value varies according to temperature, and may be formed by mixing and sintering oxides such as copper, manganese, nickel, cobalt, chromium, and iron. Such a thermistor has an advantage of being small in size and capable of measuring even a rapid temperature change or a minute temperature change.
[60]
As such, the temperature information measured by the temperature sensor 450 may be transmitted to another device outside the battery module. For example, when a temperature is measured by the temperature sensor 450 , the measured temperature information is transmitted to a battery management system (BMS) outside the battery module, and may be used to control the battery module. To this end, the battery module may include a temperature measuring cable (not shown) having one end connected to the temperature sensor 450 . A connector may be provided at the other end of the cable, and the connector may be connected to an external device such as a BMS.
[61]
5 and 6 , the temperature sensor 450 according to the present embodiment may be located on the flexible printed circuit board 490 . A compression pad 480 may be formed on the flexible printed circuit board 490 . The compression pad 480 may be formed of polyurethane foam. When the compression pad 480 is added, the durability of the bridge 500 may be improved. The compression pad 480 may be coupled to the bridge 500 by the first adhesive layer 470a and to the flexible printed circuit board 490 by the second adhesive layer 470b. The adhesive layer 470 including the first adhesive layer 470a and the second adhesive layer 470b may be a double-sided tape. A part of the flexible printed circuit board 490 may be connected to the temperature sensor 450 to transmit sensed temperature information to the BMS outside the battery module. The temperature sensor 450 according to the present embodiment is positioned adjacent to the battery cell 110 according to the rotation of the bridge 500 , thereby detecting a temperature according to heat generated in the battery cell 110 .
[62]
FIG. 7 is an enlarged view of part Q of FIG. 1 . FIG. 8 is a partial view schematically showing the inside of part Q of FIG. 1 . 9 is a cross-sectional view taken along the cutting line I-I' of FIG. 7 . 7 to 9 are for explaining a temperature sensor according to a comparative example.
[63]
7 to 9 , a portion of the cover plate 40 of FIG. 1 is cut to form an elastic member 21 . The flexible printed circuit board 25 is positioned at the bottom of the elastic member 21 . One end of the flexible printed circuit board 25 is formed along the direction in which the elastic member 21 extends, and most of the elastic member 21 may overlap the flexible printed circuit board 25 . A compression pad 23 is positioned between the elastic member 21 and one end of the flexible printed circuit board 25 . An adhesive layer 24 is formed on each of the upper and lower surfaces of the compression pad 23 , and specifically, the first adhesive layer 24a is positioned between the compression pad 23 and the elastic member 21 , and the compression pad 23 . A second adhesive layer 24b may be positioned between the flexible printed circuit board 25 and the flexible printed circuit board 25 . The first adhesive layer 24a and the second adhesive layer 24b are double-sided tapes. The flexible printed circuit board 25 may be coupled to the elastic member 21 using such a double-sided tape.
[64]
In this comparative example, the temperature sensor 26 is mounted between the compression pad 23 and the battery cell 11 . When the elastic member 21 is pressed, the temperature sensor 26 detects the temperature of the battery cell 11 . On the other hand, since the temperature sensor 450 of FIG. 6 according to the present embodiment is attached to the bridge 500 rather than the cover plate and assembled through the rotation shaft 495, it is assembled during the assembly process of the battery module having a U-shaped frame structure. It can be assembled in a position to minimize interference and sense the temperature of the battery cell without a cover plate. Therefore, according to this embodiment, there is an advantage in terms of weight and space reduction and cost reduction by removing the cover plate of the comparative example. In addition, in the comparative example, since the temperature sensor 26 is assembled to the lower part of the cover plate in a fixed state, it is difficult to confirm whether the temperature sensor 26 is in the correct position, but the temperature sensor 450 according to this embodiment is Since it is attached to the bridge 500 , it is possible to check and adjust whether the temperature sensor 450 is in the correct position before assembling it to the bus bar frame 320 . In addition, in the process of inserting the mono frame 20 according to the comparative example into the battery cell stack 12, it is possible to reduce production defects caused by jamming of the cover plate.
[65]
Meanwhile, one or more battery modules according to an embodiment of the present invention may be packaged in a pack case to form a battery pack.
[66]
The above-described battery module and battery pack including the same may be applied to various devices. Such a device may be applied to transportation means such as an electric bicycle, an electric vehicle, and a hybrid vehicle, but the present invention is not limited thereto and is applicable to various devices that can use a battery module and a battery pack including the same, and this It belongs to the scope of the invention.
[67]
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
[68]
Explanation of symbols
[69]
100: battery module
[70]
200: upper plate
[71]
210: U-shaped frame
[72]
400: connection signal unit
[73]
450: temperature sensor
[74]
500: bridge

WE CLAIMS

A battery cell stack in which a plurality of battery cells are stacked, a U-shaped frame accommodating the battery cell stack and an open top, an upper plate covering the battery cell stack on the open U-shaped frame upper portion, the battery cell Bus bar frames respectively formed at both ends of the stack, a signal connection part positioned between the upper plate and the battery cell stack, and connecting the bus bar frames respectively formed on both ends of the battery cell stack, and adjacent to the signal connection part A battery module comprising a bridge hinged to a bus bar frame, and having a temperature sensor attached to the bridge.
[Claim 2]
The battery module of claim 1, wherein the bridge has a rotation axis.
[Claim 3]
The battery module of claim 2, further comprising a compression pad positioned between the bridge and the battery cell stack.
[Claim 4]
The battery module of claim 3, further comprising a double-sided tape positioned between the compression pad and the battery cell stack.
[Claim 5]
The battery module of claim 4, wherein the temperature sensor is a thermistor element.
[Claim 6]
The battery module of claim 1, wherein a surface of the battery cell stack perpendicular to the stacking direction of the plurality of battery cells is mounted on the bottom of the U-shaped frame.
[Claim 7]
The method of claim 6, further comprising an end plate respectively coupled to the open both sides of the U-shaped frame, the open both sides of the U-shaped frame are opposite to each other based on the direction in which the electrode leads of the battery cell stack protrude. battery module.
[Claim 8]
The battery module of claim 7 , wherein the U-shaped frame includes a bottom portion and two side portions facing each other while being connected by the bottom portion, and a distance between the two side portions is equal to the width of the upper plate.
[Claim 9]
The battery module of claim 1, wherein the signal connection part is formed of a flexible flat cable (FFC) to connect bus bar frames at both ends of the battery cell stack.
[Claim 10]
A battery pack comprising the battery module according to claim 1 .