KR20210103832A - 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; bus bar frames respectively positioned at a front side and a rear side of the battery cell laminate; and a temperature measuring assembly which is mounted at the bus bar frames to be in contact with at least one of the battery cells. According to the present invention, stability of the battery module can be improved.

Description

A battery module and a 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 a temperature measuring assembly 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 large-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 to the at least one battery module to configure the battery pack. How to do it is common

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

1 is a perspective view of a conventional battery module 10, and FIG. 2 is a bus bar frame 31 and 32, a flexible circuit board 40, and a cover plate 90 included in the battery module 10 of FIG. is an inverted perspective view, and FIG. 3 is an exploded perspective view showing the flexible printed circuit board 40 and the cover plate 90 separated.

1 to 3 , the conventional battery module 10 includes a battery cell stack 20 in which a plurality of battery cells are stacked, and a cover plate 90 positioned on the top of the battery cell stack 20 . , and bus bar frames 31 and 32 positioned on the front and rear surfaces of the battery cell stack 20 and the bus bar 30 mounted on the bus bar frames 31 and 32 .

A flexible printed circuit (FPC, flexible printed circuit) 40 for voltage measurement and temperature measurement of the battery cells may be positioned between the battery cell stack 20 and the cover plate 90 .

The cover plate 90 located on the upper end of the flexible printed circuit board 40 can prevent damage to the flexible printed circuit board 40 that may occur when being accommodated in a module frame (not shown).

The flexible circuit board 40 may include a temperature measuring unit 41 in contact with the battery cell stack 20 and a voltage measuring unit 42 in close contact with the bus bar 30 .

At this time, in the conventional battery module 10 , the temperature measuring unit 41 is disposed on the upper portion of the battery cell stack 20 due to structural and spatial constraints. As the temperature measuring unit 41 is included in the flexible circuit board 40, the temperature measuring unit 41 is inevitably limited to a chip type thermistor capable of SMD processing, and the flexible circuit board ( 40) had no choice but to form a complex structure. In addition, the area of the flexible printed circuit board 40 is increased due to the upper arrangement of the temperature measuring unit 41 , so that the manufacturing cost of the battery module 10 is increased, and the degree of freedom in design is inhibited.

Embodiments of the present invention are proposed to solve the above problems of the previously proposed methods, and a battery module capable of reducing the cost of the circuit unit and improving the degree of freedom of design through the movement of the position of the temperature measuring assembly and the same It aims at providing the battery pack containing.

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; a bus bar frame positioned on the front and rear surfaces of the battery cell stack, respectively; and a temperature measuring assembly mounted on the bus bar frame and in contact with at least one of the battery cells.

The temperature measuring assembly may include a measuring unit for measuring a temperature in contact with at least one of the battery cells, and an elastic unit positioned between the measuring unit and the bus bar frame.

The elastic part may include at least one of a spring, an elastic rubber (Rubber), and an elastic pad (PAD).

The measuring unit may include at least one of a thermistor, a resistance thermometer detector (RTD), and a thermocoupler.

The temperature measuring assembly may further include an injection member surrounding the measuring part.

The battery module may further include a circuit unit positioned on the battery cell stack, and the circuit unit may include a flexible printed circuit (FPC) or a flexible flat cable (FFC).

The flexible circuit board and the flexible flat cable may have a shape extending in a straight line.

The electrode leads of the battery cell may protrude toward the bus bar frame.

The temperature measuring assembly may be positioned between two adjacent electrode leads among the electrode leads.

The two adjacent electrode leads may be bent in a direction away from each other.

According to embodiments of the present invention, it is possible to reduce the cost of the circuit unit and improve the degree of freedom in design by moving the position of the temperature measuring assembly including the thermistor.

In addition, since the temperature measuring assembly may be located inside the bus bar frame, it is possible to prevent damage due to external shock or vibration.

In addition, it is easier to sense the temperature measurement assembly with respect to the temperature change of the battery cell, thereby improving the safety of the battery module.

1 is a perspective view of a conventional battery module.
FIG. 2 is a perspective view showing the bus bar frame, the flexible circuit board, and the cover plate included in the battery module of FIG. 1 upside down.
3 is an exploded perspective view showing the flexible circuit board and the cover plate of FIG. 2 separated.
4 is a perspective view of a battery module according to an embodiment of the present invention.
5 is an exploded perspective view of the battery module of FIG. 4 .
6 is a perspective view of a battery cell included in the battery module of FIG. 4 .
7 is a cross-sectional view taken along the cutting line A of FIG. 4 .
8 is a cross-sectional view taken along the cutting line B of FIG. 4 .

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 implement them. 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 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.

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.

4 is a perspective view of the battery module 100 according to an embodiment of the present invention, and FIG. 5 is an exploded perspective view of the battery module 100 of FIG. 4 .

4 and 5 , the battery module 100 according to an embodiment of the present invention includes a battery cell stack 200 in which a plurality of battery cells 110 are stacked, and a battery cell stack 200 . and a temperature measuring assembly mounted on the bus bar frames 310 and 320 positioned on the front and rear sides, respectively, and the bus bar frames 310 and 320 and contacting at least one of the battery cells 110 . The temperature measuring assembly will be described in detail with reference to FIGS. 7 and 8 .

6 is a perspective view of the battery cell 110 included in the battery module 100 of FIG. 4 . More specifically, it is a view showing one of the battery cells 110 included in the battery cell stack 200 .

Referring to FIG. 6 , the battery cell 110 is preferably a pouch-type battery cell. For example, the battery cell 110 according to the present embodiment has a structure in which two electrode leads 150 face each other and protrude from one end 114a and the other end 114b of the battery body 113, respectively. has In more detail, the electrode lead 150 is connected to the electrode assembly (not shown) and protrudes from the electrode assembly (not shown) to the outside of the battery cell 110 .

Meanwhile, in the battery cell 110 , both ends 114a and 114b of the battery case 114 and one side 114c connecting them are adhered in a state in which an electrode assembly (not shown) is accommodated in the battery case 114 . It can be manufactured by In other words, the battery cell 110 according to the present embodiment has a total of three sealing parts 114sa, 114sb, 114sc, and the sealing parts 114sa, 114sb, 114sc are sealed by a method such as thermal fusion. , the other one side may be formed of a connection part 115 .

Referring back to FIG. 5 , the battery cells 110 of FIG. 6 may be stacked along the y-axis direction to form the battery cell stack 200 . Accordingly, the electrode leads 150 of each of the plurality of battery cells 110 protrude toward the front (x-axis direction) and the rear surface (the opposite direction of the x-axis) of the battery cell stack 200 .

According to the direction in which the electrode lead 150 protrudes, the bus bar frames 310 and 320 may be respectively positioned on the front and rear surfaces of the battery cell stack 200 (in the x-axis direction and the x-axis direction opposite direction). Specifically, the first bus bar frame 310 may be positioned on the front surface (x-axis direction) of the battery cell stack 200 , and the second bus bar frame 310 may be positioned on the rear surface (opposite the x-axis direction) of the battery cell stack 200 . A bus bar frame 320 may be positioned. That is, the electrode lead 150 of the battery cell 110 may protrude toward the bus bar frames 310 and 320 .

7 is a cross-sectional view taken along the cutting line A of FIG. 4 , and FIG. 8 is a cross-sectional view taken along the cutting line B of FIG. 4 .

Referring to FIGS. 7 and 8 together with FIG. 5 , the battery module 100 according to the present embodiment includes a temperature measurement assembly 500 , and the temperature measurement assembly 500 includes bus bar frames 310 and 320 . It is mounted on the battery cell stack 200 may be in contact.

Hereinafter, the first busbar frame 310 will be described as a reference, but the temperature measuring assembly 500 may also be mounted on the second busbar frame 320 . That is, the temperature measuring assembly 500 in the present invention may be mounted on at least one of the first bus bar frame 310 and the second bus bar frame 320 .

The temperature measuring assembly 500 includes a measuring unit 510 measuring a temperature in contact with at least one of the battery cells 110 , and an elastic unit positioned between the measuring unit 510 and the first bus bar frame 310 . 520) may be included. Furthermore, the temperature measuring assembly 500 may further include an injection member 530 surrounding the measuring unit 510 .

The measuring unit 510 may include at least one of a thermistor, a resistance thermometer detector (RTD), and a thermocoupler.

A thermistor is a temperature measuring device using a resistance value change characteristic according to a temperature change of a semiconductor. RTD is a temperature measuring device that uses the characteristic that resistance value changes according to temperature, and is generally made using 0.02mm platinum wire. A thermocoupler is a temperature measuring device in which two types of joined metals generate an electromotive force in response to temperature.

The measurement unit 510 may be directly or indirectly connected to an external Battery Management System (BMS) or the like. The measurement unit 510 measures and senses the temperature of the battery cell 110 , outputs it as an electrical signal, and transmits it through a module connector (not shown), thereby transmitting temperature information of the battery cell 110 to an external BMS. .

Meanwhile, the battery module 100 according to the present embodiment may further include a circuit unit 400 positioned on the battery cell stack 200 . The circuit unit 400 may include a flexible printed circuit (FPC) or a flexible flat cable (FFC). The circuit unit 400 transmits the measured voltage of the battery cell 110 to a Battery Mamagement System (BMS) through a module connector (not shown), and phenomena such as overvoltage, overcurrent, and overheating of the battery cell 110 . is configured to detect

In addition, the battery module 100 may further include a cover plate 900 disposed on the circuit unit 400 to protect the circuit unit 400 .

Unlike the conventional battery module 10 (see FIGS. 1 to 3 ), the battery module 100 according to this embodiment includes a temperature measurement assembly 500 for measuring the temperature of the battery cells 110 in the battery cell stack ( 200 ) may be mounted on the bus bar frames 310 and 320 , rather than located on the upper part, and located on the front or rear side of the battery cell stack 200 .

Specifically, the temperature measuring assembly 500 may include a thermistor wrapped by the injection member 530 instead of a chip type thermistor, and is not located on the battery cell stack 200 , but rather It may be located in the inner accommodation space of the bus bar frames 310 and 320 . The temperature measuring assembly 500 does not need to be directly connected to the circuit part 400 and may be configured independently.

That is, the position of the temperature measuring assembly 500 is not limited to the circuit unit 400 , and the degree of freedom in design can be increased by freely adjusting the position of the temperature measuring assembly 500 , and the cost can be reduced by reducing the area of the circuit unit 400 . As a result, unlike the conventional battery module 10, the circuit portion 400 of the flexible circuit board or the flexible flat cable is configured to extend in a straight line, so that the structure can be simplified. When designing the circuit unit 400 , there is no restriction to provide a separate temperature measuring member, so a more free design is possible.

In addition, a flexible flat cable that is formed as a flexible cable and can be bent may be applied to the circuit unit 400 by changing the position of the temperature measuring assembly 500 as described above. That is, since the temperature measuring assembly 500 is not directly connected to the circuit unit 400 , a material to be applied to the circuit unit 400 may be freely selected without limitation.

In addition, since the temperature measuring assembly 500 mounted on the first busbar frame 310 is positioned between the first busbar frame 310 and the battery cell stack 200 , external factors such as external shock or vibration It is possible to protect the temperature measuring assembly 500 from damage to the temperature measuring assembly 500 can be prevented.

Meanwhile, the injection member 530 may be manufactured through injection molding, and may include at least one of polypropylene (PP), polycarbonate-acrylonitrile butadiene styrene (PC-ABS), modified polyphenylene oxide (MPPO), and epoxy.

The elastic part 520 positioned between the measuring part 510 and the first bus bar frame 310 is a member having elastic force, and may include at least one of a spring, an elastic rubber, and an elastic pad PAD. can 7 and 8 show the elastic part 520 in the form of a spring spring.

Due to the elastic force of the elastic part 520 , the measuring part 510 and the injection member 530 receive a force in the direction of the battery cell 110 . The assembly tolerance is absorbed by this elastic force, so that sufficient contact between the measuring unit 510 and the at least one battery cell 110 is possible. Also, the measuring unit 510 may be fixed between the first bus bar frame 310 and the battery cell stack 200 by the elastic unit 520 . In addition, since the measuring unit 510 can be in close contact with the battery body 113 (refer to FIG. 6 ) of the battery cell 110 , the temperature change of the battery cell 110 can be more accurately detected, such as overvoltage, overcurrent, overheating, etc. It is easy to detect the phenomenon of the battery module, so it is possible to improve the safety of the battery module.

As described above in FIG. 5 , the electrode lead 150 of the battery cell 110 may protrude toward the bus bar frames 310 and 320 . The electrode leads 150 of the battery cell 110 may be electrically connected through the bus bar 300 mounted on the bus bar frames 310 and 320 .

Specifically, referring to FIG. 8 , the electrode leads 150 of the battery cell 110 may pass through the slit formed in the first bus bar frame 310 and then be bent to be connected to the bus bar 300 . The electrode lead 150 and the bus bar 300 may be bonded to each other through welding, but if electrical connection is possible, the bonding method is not limited thereto, and may be implemented through various embodiments.

In this case, the temperature measuring assembly 500 may be positioned between two adjacent electrode leads 150a and 150b among the electrode leads 150 . In addition, two adjacent electrode leads 150a and 150b may be bent in a direction away from each other. Specifically, the electrode lead 150a located on the left side of the temperature measurement assembly 500 may be bent to the left, and the electrode lead 150b located on the right side of the temperature measurement assembly 500 may be bent to the right.

As such, since the temperature measuring assembly 500 is positioned in the space between the electrode leads 150a and 150b, the space in the battery module 100 can be efficiently utilized. In other words, since the temperature measuring assembly 500 is not located on the top of the battery cell stack 200 , the height of the battery module 100 can be reduced compared to the conventional battery module 10 , and the electrode leads Since it utilizes the space that already exists between (150a, 150b), there is an advantage in terms of space utilization.

On the other hand, when the battery module 100 is operating, the electrode lead 150 part of the battery cell 110 may be more concentrated than other parts of the heat. At this time, since the temperature measuring assembly 500 according to the present embodiment is in contact with the portion adjacent to the electrode lead 150 among the battery cells 110 , the temperature change, in particular, the temperature rise of the battery cell 110 is more clearly and quickly can detect

Referring back to FIG. 5 , the battery cell stack 200 , the bus bar frames 310 and 320 , the circuit unit 400 , and the cover plate 900 may be accommodated in the module frame 600 . This module frame 600 has front (x-axis direction) and back (x-axis direction) open, the upper surface (z-axis direction), the lower surface (opposite the z-axis direction) and both sides (y-axis direction and the opposite direction) ) may be an integrated structure. The battery cell stack 200 and the like may be accommodated in the inner space of the module frame 600 through the front surface or the rear surface. An end plate 700 may cover the open front and rear surfaces of the module frame 600 , respectively.

The module frame 600 and the end plate 700 preferably have a predetermined strength to protect the battery cell stack 200 and other electrical components from external impact, and for this purpose, include a metal material, particularly aluminum. can

The module frame 600 and the end plate 700 may be bonded to each other through welding, but the bonding method is not limited thereto, and may be implemented through various embodiments.

A thermally conductive resin layer 800 coated with thermal conductive resin may be formed between the battery cell stack 200 and the lower surface of the module frame 600 . The thermally conductive resin may include a thermally conductive adhesive material, and specifically, may include at least one of a silicone material, a urethane material, and an acrylic material.

The thermally conductive resin may serve to fix each of the battery cells 110 constituting the battery cell stack 200 by being liquid during application but solidified after application. In addition, it is possible to prevent overheating of the battery module 100 by quickly transferring the heat generated in the battery cell 110 toward the lower surface of the battery module 100 due to excellent thermal conductivity.

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. Specifically, it may be applied to transportation means such as an electric bicycle, an electric vehicle, a hybrid, etc., but is not limited thereto and may be applied to various devices that can use a secondary battery.

In this embodiment, terms indicating directions such as front, back, left, right, up, and down are used, but these terms are for convenience of explanation only, and may vary depending on the position of the object or the position of the observer. .

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 module
110: battery cell
150: electrode lead
200: battery cell stack
300: bus bar
310, 320: bus bar frame
400: circuit unit
500: temperature measurement assembly
510: measurement unit
520: elastic part
530: injection member

Claims (11)

a battery cell stack in which a plurality of battery cells are stacked;
a bus bar frame positioned on the front and rear surfaces of the battery cell stack, respectively; and
and a temperature measuring assembly mounted on the bus bar frame and in contact with at least one of the battery cells. In claim 1,
The temperature measuring assembly includes a battery module including a measuring unit for measuring a temperature in contact with at least one of the battery cells, and an elastic unit positioned between the measuring unit and the bus bar frame. In claim 2,
The elastic part is a battery module including at least one of a spring, an elastic rubber (Rubber), and an elastic pad (PAD). In claim 2,
The measuring unit includes at least one of a thermistor, a resistance thermometer detector (RTD), and a thermocoupler. In claim 2,
The temperature measuring assembly further includes an injection member surrounding the measuring part. In claim 1,
Further comprising a circuit portion located on the battery cell stack,
The circuit part is a battery module comprising a flexible printed circuit (FPC) or a flexible flat cable (FFC). In claim 6,
The flexible circuit board and the flexible flat cable are in the form of extending in a straight line battery module. In claim 1,
The electrode leads of the battery cells protrude toward the bus bar frame. In claim 8,
The temperature measuring assembly is a battery module positioned between two adjacent electrode leads among the electrode leads. In claim 9,
The two adjacent electrode leads are bent in a direction opposite to each other. A battery pack comprising at least one battery module according to claim 1 .

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