KR20210071552A - Battery module and battery pack including the same - Google Patents

Abstract

A battery module according to one embodiment of the present invention comprises: a battery cell laminate in which a plurality of battery cells are laminated; busbar frames respectively formed on a front side and a rear side of the battery cell laminate; a connection part which connects the busbar frames; and a connection part connector which is combined with the connection part and mounted at the busbar frames. The connection part is formed with a flexible flat cable (FFC) and positioned at an upper side of the battery cell laminate, and the connection part connector is mounted at the busbar frames in a vertical direction. According to the present invention, energy density of the battery module is increased and an installation space of the battery module is ensured by reducing the height of the battery module.

Description

A battery module and a battery pack including the same {BATTERY MODULE AND BATTERY PACK INCLUDING THE SAME}

The present invention relates to a battery module and a battery pack including the same, and more particularly, to a battery module having an improved sensing connection and a battery pack including the same.

Secondary batteries are receiving a lot of attention as an energy source in various product groups such as mobile devices and electric vehicles. Such a secondary battery is a powerful energy resource that can replace the use of conventional products using fossil fuels, and is in the spotlight as an eco-friendly energy source because no by-products are generated due to energy use.

Recently, as the need for a high-capacity secondary battery structure, including the use of secondary batteries as an energy storage source, increases, the demand for a battery pack having a multi-module structure in which a plurality of secondary batteries are assembled in series/parallel connected battery pack is increasing .

On the other hand, when configuring a battery pack by connecting a plurality of battery cells in series/parallel, a battery module including at least one battery cell is configured, and other components are added using the at least one battery module to form a battery pack. The general way to configure

Such a battery module is configured to include a battery cell stack in which a plurality of battery cells are stacked, a bus bar frame respectively formed at both ends of the battery cell stack, and a connection unit connecting the bus bar frames at both ends.

1 is an exploded perspective view of a conventional battery module 10 .

Referring to FIG. 1 , the conventional battery module 10 includes a battery cell stack 20 in which a plurality of battery cells are stacked, a mono frame 70 accommodating the battery cell stack 20 , and an open structure of the mono frame. It includes an end plate 80 covering the front and rear surfaces.

Between the battery cell stack 20 and the end plate 80 , the bus bar frames 32 and 33 , the bus bar 40 , and the insulating member 60 are sequentially positioned.

A flexible printed circuit (FPC, flexible printed circuit) 50 for voltage sensing and temperature sensing of the battery cells may be positioned on the upper surface of the battery cell stack 20 .

Conventionally, the bus bar frames 32 and 33 at both ends are connected through the flexible circuit board 50 , and the cover plate 31 is installed on the upper end of the flexible circuit board 50 to be accommodated in the mono frame 70 . It was intended to prevent damage to the flexible printed circuit board 50 that may occur when this occurs.

However, as shown in FIG. 1 , due to the cover plate 31 disposed on the flexible circuit board 50 , the height of the battery module also increases by the thickness thereof, and there is a problem in that the weight of the module increases.

As such, when the size of the battery module is increased, more installation space is required when the battery module is installed, and when the battery module is installed in a vehicle, there is a problem in that the driving performance of the vehicle is reduced.

In addition, when the weight of the battery module increases, the overall utility of the battery module decreases, and similarly, when a heavy battery module is installed in the vehicle, the driving performance of the vehicle decreases and fuel efficiency decreases.

FIG. 2 is an enlarged perspective view of the flexible printed circuit board 50 of FIG. 1 .

Referring to FIG. 2 , the flexible circuit board 50 includes a body part 51 and a connector 54 connected to one of both ends 52 and 53 of the body part. The connector 54 may be configured to transmit and receive signals to and from an external control device to control the plurality of battery cells.

At this time, in the prior art, the connector 54 was designed to be assembled in a horizontal direction, and it was necessary to bend the one end 52 of the main body 51 connected to the connector 54 twice or more. For this, additional space is required, so space utilization is reduced, and structural weakness in which an external force is applied to the fixed connector 54 may occur.

An object of the present invention is to provide a battery module with improved space utilization and automatic assembly of a connection part formed of a flexible flat cable, and a battery pack including the same.

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.

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; bus bar frames respectively formed on the front and rear surfaces of the battery cell stack; a connector connecting the bus bar frame; and a connector coupled to the connector and mounted on the bus bar frame, wherein the connector is formed of a flexible flat cable (FFC) and is located on the upper side of the battery cell stack, the connector is It is vertically mounted on the bus bar frame.

Both ends of the connection part may be bent in a vertical direction toward the connection part connector.

The connection unit may include: a connection body positioned on an upper surface of the battery cell stack; and a connection cable bent in a vertical direction at both ends of the connection body and connected to the connection part connector.

The connector connector may include an insert into which the connector is inserted, and an opening direction of the insert may face upward.

The connection part may be formed in a flexible flat shape.

Two guide lines are formed on both sides of the connection part, and the bus bar frame may be positioned between the two guide lines.

The connection part may be formed to be parallel to a longitudinal direction of one of the plurality of battery cells.

The connection part may be formed to be parallel to the longitudinal direction of the battery cell at a position corresponding to the 16th battery cell based on the outermost battery cell on one side of the plurality of battery cells.

The connection part may be coupled to the bus bar frame through an opening formed in the guide jig.

A connection part fixing part may be formed in the connection part, and the connection part may be attached to the battery cell stack through the connection part fixing part.

The connection part fixing part may be located at both lower ends of the connection part so that the connection part may be attached to the battery cell stack.

In the battery module and the battery pack including the same according to an embodiment of the present invention, the height of the battery module is reduced due to the removal of the cover plate, thereby increasing the energy density of the battery module itself and securing the installation space of the battery module. have. When such a battery module or battery pack is installed in a vehicle, the driving performance may be improved.

In addition, in the battery module and the battery pack including the same according to an embodiment of the present invention, the weight of the battery module is reduced due to the removal of the cover plate, thereby enhancing the utility of the battery module and fuel efficiency when the battery module is installed in a vehicle. has the effect of improving

In addition, since the connector and the connector formed of the flexible flat cable are mounted in the vertical direction, it is advantageous for automatic assembly, the manufacturing process is improved, the space utilization is increased, and the cost can be reduced.

Effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is an exploded perspective view of a conventional battery module.
FIG. 2 is an enlarged perspective view of the flexible printed circuit board of FIG. 1 .
3 is an exploded perspective view of a battery module according to an embodiment of the present invention.
4 is a view showing a state in which the connection part of FIG. 3 and the bus bar frame are combined.
FIG. 5 is a top view of a connection part positioned on the battery cell stack of FIG. 3 .
FIG. 6 is an enlarged partial view of part “A” of FIG. 5 .
7 is a plan view of the connector and the connector of FIG. 6 viewed from above.
8 is a side view of the connector and the connector of FIG. 7 as viewed from the side;
9 is an enlarged front view showing a state in which the connector connector is mounted to the connector mounting part.
FIG. 10 is a side view of the connector and connector mounting part of FIG. 9 as viewed from the side;
11 is a view showing a state of a guide jig according to an embodiment of the present invention.

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 many different forms and is not limited to the embodiments described herein.

In order to clearly explain the present invention, parts irrelevant to the description are omitted, and the same reference numerals are given to the same or similar elements throughout the specification.

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.

Also, 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 gravity no.

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.

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.

Hereinafter, a battery module according to an embodiment of the present invention will be described.

3 is an exploded perspective view of a battery module according to an embodiment of the present invention, and FIG. 4 is a view showing a state in which the connection part of FIG. 3 and the bus bar frame are combined.

3 and 4 , in the battery module according to an embodiment of the present invention, a battery cell stack in which a plurality of battery cells 100 are stacked, and a bus formed on the front and rear surfaces of the battery cell stack, respectively and a bar frame 300 , a connector 400 connecting the bus bar frame 300 , and a connector 430 coupled to the connector 400 and mounted on the bus bar frame 300 . The connection part 400 is formed of a flexible flat cable (FFC) and is located on the upper side of the battery cell stack, and the connection part connector 430 is vertically mounted on the bus bar frame 300 .

The battery module in this embodiment is formed in a U-shaped structure of the bottom and both sides of the lower frame 210 to cover the lower surface and both sides of the battery cell stack, and the upper frame to cover the upper surface of the battery cell stack. (220) may be further included.

The battery cell 100 is a secondary battery and may be configured as a pouch-type secondary battery. The battery cells 100 may be configured in plurality, and the plurality of battery cells 100 may be stacked to each other so as to be electrically connected to each other to form a battery cell stack. Although not specifically illustrated, each of the plurality of battery cells may include an electrode assembly, a battery case, and an electrode lead protruding from the electrode assembly. Meanwhile, as shown in FIG. 3 , the plurality of battery cells 100 may be disposed parallel to both sides of the lower frame 210 and sequentially stacked along the y-axis direction.

The battery cell stack is formed surrounded by a lower frame 210 that covers a lower surface and both side surfaces and an upper frame 220 that covers the upper surface. At this time, the battery cell stack is inserted on the lower frame 210, and then the battery cell stack may be mounted inside the frame by a method of covering the upper side of the battery cell stack through the upper frame.

The lower frame 210 and the upper frame 220 are coupled to each other to accommodate the battery cell stack located inside the frame. In this case, the two frames may be joined through welding, but the method of joining the frames is not limited thereto, and may be implemented through various embodiments.

A bus bar frame 300 is formed on the front and rear surfaces of the battery cell stack. The bus bar frame 300 includes a bus bar and a cell connection board, and may electrically connect the electrode leads of the plurality of battery cells 100 through a bus bar mounted on the bus bar frame 300 . Specifically, the electrode leads of the battery cell 100 may pass through a slit formed in the bus bar frame 300 and then be bent to be connected to the bus bar.

The bus bar frame 300 is formed of a first bus bar frame 310 formed on one side of the battery cell stack and a second bus bar frame 320 formed on the other side of the battery cell stack, so that the battery cell stack is stacked. The electrode leads on both sides of the body may be electrically connected to each other.

End plates 311 and 312 may be coupled to the open front and rear surfaces of the combined lower frame 210 and the upper frame 220 . That is, the end plates 311 and 312 may cover the first and second bus bar frames 310 and 320 .

The end plates 311 and 312 protect various electrical components provided in the first and second bus bar frames 310 and 320 from external impact, and at the same time, between the first and second bus bar frames 310 and 320 and an external power source. Electrical connections can be guided. An insulating member (not shown) is inserted between the end plates 311 and 312 and the first and second bus bar frames 310 and 320 , so that unnecessary connections between the bus bar frames 310 and 320 and the end plates 311 and 312 are unnecessary. Electrical connections may be interrupted.

The connection unit 400 is provided between the first and second bus bar frames 310 and 320 to electrically connect the two bus bar frames. 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 circuit board is covered to prevent damage to the flexible printed circuit board. plate was installed. However, according to an embodiment of the present invention, the cover plate that protects and supports the flexible circuit board is removed, and the flexible flat cable (FFC: Flexible) formed of a flat cable that does not require a protective member such as a cover plate instead of the flexible circuit board Connect the two busbar frames using a flat cable).

By connecting the two busbar frames through FFC in this way, the height of the battery module is reduced to increase the energy density of the battery itself, it is possible to secure the installation space for the battery module, and when the battery module is installed in a vehicle, driving performance and fuel efficiency are improved can do it

As described above, the connection part 400 formed of FFC according to an embodiment of the present invention is positioned between the upper frame 220 and the battery cell 100 stack. In more detail, an insulating member (not shown) is formed on the upper surface of the battery cell 100 stack, and the connection part 400 is positioned between the insulating member (not shown) and the upper frame 220 .

The connection part 400 may be formed to be parallel to the longitudinal direction (x-axis direction) of one of the plurality of battery cells 100 . According to an embodiment of the present invention, the connection part 400 is formed to be parallel to the longitudinal direction of the battery cell at a position corresponding to the 16th battery cell based on the outermost battery cell on one side of the plurality of battery cells 100 . can be In this way, by matching the position of the connection part with one of the battery cells, the assembly of the connection part 400 can be made more easily.

FIG. 5 is a view of the connection part 400 positioned on the battery cell stack of FIG. 3 as viewed from above. FIG. 6 is an enlarged partial view of part A of FIG. 5 .

4 to 6 , as described above, the battery module in this embodiment includes a connector connector 430 coupled to the connector 400 and mounted on the bus bar frame 300 , and the connector connector 430 . ) is vertically mounted on the bus bar frame 300 .

Accordingly, in order to be connected to the connector connector 430 , both ends of the connector 400 may be bent in a vertical direction toward the connector connector 430 .

7 is a plan view of the connector 400 and the connector 430 of FIG. 6 as viewed from above, and FIG. 8 is a side view of the connector 400 and the connector 430 of FIG. 7 as viewed from the side.

Referring to FIGS. 7 and 8 , the connection unit 400 is bent in the vertical direction at both ends of the connection body 410 and the connection body 410 located on the upper side of the battery cell stack to connect the connection unit connector 430 and connected to it. A cable 420 may be included.

As described above, both ends of the connection unit 400 are bent in the vertical direction toward the connection unit connector 430 . Specifically, the connection cable 420 of the connection unit 400 is in a vertical direction, particularly in a downward direction (opposite the z-axis direction). ) may be bent to be connected to the connector 430 .

An insertion part 431 into which the connection cable 420 is inserted may be formed in the connector connector 430 , and depending on the bending direction of the connection cable 420 , the insertion part 431 has an opening direction in the upper part (z-axis). direction) can be directed.

In the case of the conventional battery module, the connector connected to the flexible circuit board or the flexible flat cable is designed to be mounted on the bus bar frame in the horizontal direction, so the flexible circuit board or the flexible flat cable is bent twice or more, and the bending is the y-axis. Excessive bending of the board or cable occurred because it was made twice to face each direction and the opposite direction. That is, in the prior art, the length of the board or cable had to be increased, an additional space was required for assembly, and there was a risk of damage to the flexible circuit board or the flexible flat cable during the assembly process.

However, in one embodiment of the present invention, the connector connector 430 is mounted in the vertical direction on the bus bar frame, and accordingly, it is sufficient for the connecting cable 420 to be bent only in the vertical direction, particularly in the downward direction. Accordingly, it is possible to reduce the space for coupling the connector 400 and the connector 430 in the battery module, and it is possible to shorten the length of the connector 400 of the flexible flat cable, thereby reducing the cost.

In addition, the FFC connector such as the connector 430 is a small device, and assembly is difficult. Therefore, if the assembly is done manually, the takt time is long and the completeness of assembly is not good, which is fatal to the yield. Since the connector 430 in the present invention is designed to be vertically mounted on the bus bar frame, it is easier to implement as an automated process, and the process time can be greatly reduced. That is, it is possible to improve the yield and assembly completeness.

In addition, since the number of times that the connection cable 420 is bent is reduced and excessive bending or twisting is not required, the amount of stress exerted on the connection part 400 can be reduced.

Meanwhile, referring back to FIGS. 5 and 6 , the connection part 400 may be formed to be parallel to the longitudinal direction (x-axis direction) of the plurality of battery cells 100 . Through this, the length of the connection part 400 can be minimized, the cost of manufacturing the connection part can be reduced, and when connected to the bus bar frame 300 , it can be easily connected in the vertical direction.

A connection part fixing part 411 may be formed in the connection part 400 . The connection part fixing part 411 is located at both lower ends of the connection part 400 and attached to the battery cell stack, so that the connection part 400 can be fixed to the battery cell stack.

Meanwhile, guide lines L formed in two lines may be formed on both sides of the connection part 400 . When the battery module is viewed from the upper side to the lower side in order to connect the connecting part 400 to the first and second bus bar frames 310 and 320 provided at both ends of the battery cell 100 stack and a position within the error range, The first and second bus bar frames 310 and 320 may be coupled to be positioned between two guide lines L respectively formed on both sides of the connection part 400 . By coupling the connection part 400 to the bus bar frame 300 through the guide line L, more accurate and stable mounting of the connection part 400 is possible.

In particular, since the connector 400 and the connector 430 connected thereto in the present invention are mounted in the vertical direction on the upper surface of the battery cell stack and the bus bar frame, respectively, these guide lines L are connected to the connector 400 And it can be of great help in reducing the assembly time of each connector 430 and improving assembly completion.

The connection part 400 is formed of a flexible flat cable, that is, 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.

In addition, the connection part 400 may be formed in a flexible flat shape, that is, a flat shape. Therefore, it can be bent more flexibly compared to the case of the wire-type sensing circuit, which has a strong reaction force against bending, so that it is easy to set a certain position during automatic assembly. In addition, in the case of the wire type, an additional structure to protect the wire is required and a separate assembly process is required rather than directly applied to the battery module. However, the flexible flat cable can be directly applied to the battery module assembly without a separate protective structure.

9 is an enlarged front view of the connector connector 430 mounted on the connector mounting unit 440, and FIG. 10 is a side view of the connector connector 430 and the connector mounting unit 440 of FIG. 9 viewed from the side.

9 and 10 , as described above, the connector connector 430 is mounted on the first bus bar frame 310 in a vertical direction (opposite the z-axis direction), and is formed on the first bus bar frame 310 . The connector mounting unit 440 may be mounted in a vertical direction (a direction opposite to the z-axis).

In the connector mounting part 440 , like the insertion part 431 of the connector connector 430 , an opening into which the connector connector 430 is inserted may face an upper part (z-axis direction).

Meanwhile, as can be seen in FIG. 9 , since the connector 430 is mounted on the first bus bar frame 310 in a vertical direction (in a direction opposite to the z-axis), a horizontal space required in the assembly process can be greatly reduced.

11 is a view showing a state of the guide jig 450 according to an embodiment of the present invention.

Referring to FIG. 11 , when the connection part 400 is coupled to the bus bar frame, it may be coupled using a guide jig 450 . When the connector 400 is coupled, the guide jig 450 is positioned at a preset position on the upper portion of the battery cell stack, and the opening 450a formed in the guide jig 450 is connected to the connector 400 and the connector 430 . ) may be formed in a position and size corresponding to the bonding position and shape.

Therefore, when the connection part 400 is coupled, the connection part 400 may be inserted into the opening 450a of the guide jig 450 to be coupled to the bus bar frame 300 . By using the guide jig 450, the coupling position of the connection part 400 can be easily grasped, and precise and rapid coupling of the connection part 400 may be possible.

In particular, since the connector 400 and the connector 430 connected thereto in the present invention are mounted in a vertical direction on the upper surface of the battery cell stack and the bus bar frame, respectively, such a guide jig 450 is connected to the connector 400 . And it can be of great help in reducing the assembly time of each connector 430 and improving assembly completion.

One or more battery modules according to the present embodiment described above 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.

The battery module or battery pack 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.

Although the preferred embodiment of the present invention has 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

100: battery cell
210: lower frame
220: upper frame
300: bus bar frame
310: first bus bar frame
320: second bus bar frame
311, 312: end plate
400: connection
410: connection body
411: connection part fixing part
420: connecting cable
430: connector connector
440: connector mounting portion
450: guide jig
450a: opening

Claims (12)

a battery cell stack in which a plurality of battery cells are stacked;
bus bar frames respectively formed on the front and rear surfaces of the battery cell stack;
a connector connecting the bus bar frame; and
and a connector connector coupled to the connector and mounted on the bus bar frame;
The connection part is formed of a flexible flat cable (FFC) and is located on the upper side of the battery cell stack,
The connector connector is vertically mounted on the bus bar frame. In claim 1,
The connection part is a battery module in which both ends are bent in a vertical direction toward the connector connector. In claim 1,
The connection part,
a connection body positioned on the upper side of the battery cell stack; and
A battery module including a connecting cable bent in the vertical direction at both ends of the connecting body and connected to the connector connector. In claim 1,
The connection part connector includes an insertion part into which the connection part is inserted,
The battery module in which the opening direction of the insertion part faces upward. In claim 1,
The connection part is a battery module formed in a flexible flat shape. In claim 1,
Guide lines formed in two lines are formed on both sides of the connection part,
The bus bar frame is a battery module positioned between the two guide lines. In claim 1,
The connection part is formed to be parallel to the longitudinal direction of one of the plurality of battery cells in the battery module. In claim 7,
The connection part is formed to be parallel to the longitudinal direction of the battery cell at a position corresponding to the 16th battery cell based on the outermost battery cell on one side of the plurality of battery cells. In claim 1,
The connection part is coupled to the bus bar frame through the opening formed in the guide jig. In claim 1,
A connection part fixing part is formed in the connection part, and the connection part is attached to the battery cell stack through the connection part fixing part. In claim 10,
The connection part fixing part is positioned at both lower ends of the connection part so that the connection part is attached to the battery cell stack. A battery pack comprising at least one battery module according to claim 1 .

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