Battery module including circuit board

Abstract

The present invention provides a structure of a battery module including a plurality of battery cells stacked in a width direction to form a cell stack, wherein the cell stack includes a circuit board stacked in the width direction together with the battery cells, and the circuit board includes at least one of a temperature sensor in contact with a surface of the battery cell and a surface pressure sensor for measuring internal stress in the width direction of the cell stack.

Description

Battery module including circuit board

[0001] This application claims the benefit of priority from Republic of Korea Patent Application No. 10-2023-0099966, dated July 31, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a structure of a battery module including a cell stack in which a plurality of pouch-shaped battery cells are stacked, and a circuit board capable of measuring voltage, temperature, pressure, etc. of the cell stack.

[0003] Secondary batteries, which boast high electrical properties such as high energy density and easy applicability across a wide range of product groups, are widely used not only in portable devices but also in electric or hybrid vehicles powered by electrical power sources, as well as in power storage devices. These batteries are attracting attention as a new energy source for environmental friendliness and energy efficiency, not only because they can dramatically reduce fossil fuel use, but also because they produce no byproducts from energy use.

[0004] While small mobile devices typically use one or two or three battery cells per device, medium- to large-sized devices, such as automobiles, require high output and large capacity. Therefore, medium- to large-sized battery modules, which electrically connect multiple battery cells, are used.

[0005] Since it is desirable to manufacture medium- to large-sized battery modules with as small a size and weight as possible, square batteries and pouch-type batteries that can be stacked with high integration and have a small weight per capacity are mainly used as battery cells for medium- to large-sized battery modules.

[0006] Figure 1 illustrates the structure of a pouch-type battery cell. Referring to this, the battery cell (21) is formed by folding a metal pouch (210) in half to accommodate an electrode assembly and sealing the pouch. The pouch (210) is sealed on three sides except for the folded side, and the side opposite the folded side is sealed, folded, and taped to form a sealing portion (211), and the longitudinal ends of the pouch (210) form terrace portions (212) from which electrode leads (213) protrude.

[0007] Figures 2 and 3 illustrate the structure of a typical battery module including a circuit board. Referring to these drawings, a plurality of battery cells (10) may be connected in series and / or in parallel to form a battery module (M) in order to increase capacity and / or voltage. The battery module comprises a cell stack (2) in which a plurality of battery cells (21) are stacked in the width direction, a bus bar assembly (3) connected to the electrode lead (213) at one end in the length direction of the cell stack (2), and a housing (1) for accommodating them. The housing (1) typically includes a U-frame (11), a top plate (12), and a pair of end plates.

[0008] Meanwhile, there is a risk that the battery cell (21) may overheat and catch fire due to a short circuit or the like. If the battery cell (21) catches fire, high-temperature gas and flames may be emitted from the battery cell (21). If such high-temperature gas and flames remain within the housing (1), the ignition may spread to other battery cells, causing ignition in the module unit. In addition, the battery modules (M) may be integrated in multiple units facing each other in the front and rear to form a battery pack, and if such high-temperature gas and flames are emitted from the front and rear of the battery modules (M), the ignition may spread to other battery modules (M), causing ignition in the pack unit.

[0009] To prevent such chain reaction, it is a recent trend to provide venting holes (121) in the top plate (12) to discharge gas and flames upward. By discharging gas and flames upward in this manner, heat transfer between cells and between modules can be prevented.

[0010] Referring again to FIGS. 3 and 4, the battery module (M) may include a circuit board (23) that measures the voltage, etc. of the cell stack (2) by being connected to a bus bar (32) on the cell stack (2). Similarly, a temperature sensor (233) that is in contact with the cell stack (2) and measures the temperature of the cell stack (2) is typically connected to this circuit board (23).

[0011] However, since the circuit board (23) is positioned on the upper surface of the cell stack (2), the venting hole (121) cannot be provided in the area where the circuit board (23) and the circuit board cover (122) are provided, and thus, a problem occurs in that the venting of the center of the width direction of the cell stack (2) is not smooth. In addition, since the temperature sensor (233) has no choice but to be placed so as to be in contact with the sealing portion (211), there is also a problem in that the temperature measured by the temperature sensor (233) is difficult to represent the exact internal temperature of the cell stack (2).

[0012] In addition, a swelling phenomenon may occur in the battery cell (21) in which the electrolyte inside the battery cell evaporates and is not discharged to the outside, causing the pouch (210) to swell. This may impair the structural stability and energy density of the battery module (M) and may be a precursor to ignition, and thus, this problem also needs to be prevented.

[0013] The present invention was created under the background of the above-described prior art, and its purpose is to provide a structure of a battery module in which high-temperature gas and flames resulting from ignition of a battery cell can be smoothly discharged upward.

[0014] The present invention also aims to provide a structure of a battery module in which gas and flame can be discharged from the entire upper surface of the battery module.

[0015] Another technical object of the present invention is to provide a structure of a battery module capable of monitoring its lifespan, condition, risk of fire, etc. by including a circuit board capable of acquiring information on electrical information, temperature, internal stress, etc. of a cell stack. In particular, the present invention aims to provide a structure and arrangement of a sensor capable of accurately representing the temperature and internal stress of the cell stack when measuring the temperature and internal stress of the cell stack.

[0016] The present invention also seeks to provide a structure of a battery module in which deterioration of structural stability due to tolerance and / or swelling is minimized.

[0017] The technical objectives of the present invention are not limited to the purposes mentioned above. Other objectives and advantages of the present invention not mentioned above can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the objectives and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0018] In order to solve the above problem, the present invention provides a structure of a battery module including a plurality of battery cells that are laminated in the width direction to form a cell laminate, wherein the cell laminate includes a circuit board laminated in the width direction together with the battery cells, and the circuit board includes at least one of a temperature sensor in contact with a surface of the battery cell and a surface pressure sensor that measures internal stress in the width direction of the cell laminate.

[0019] The temperature sensor may include a thermovariable resistor (thermistor). However, any temperature sensor may be selected as the temperature sensor as long as it can come into contact with the surface of the battery cell and measure the temperature of the battery cell.

[0020] The temperature sensor may be provided at the central portion of the circuit board on a planar surface. In other words, the center of the plane of the portion of the temperature sensor that comes into contact with the battery cell may be located within a predetermined distance from the center of the widthwise side of the battery cell. The predetermined distance is preferably no more than one-third of the short side of the battery cell. Accordingly, the temperature measured by the temperature sensor can accurately represent the temperature of the cell stack.

[0021] The circuit board may include a surface pressure sensor that measures the internal stress in the width direction of the cell stack.

[0022] The above-mentioned pressure sensor may include a piezoelectric sensor. However, the pressure sensor may be selected from any sensor that is interposed within the cell stack and can measure the internal stress in the width direction of the cell stack.

[0023] The surface pressure sensor may be provided at the center of the circuit board in plan view. In other words, the center of the surface pressure sensor in plan view may be located within a predetermined distance from the center of the widthwise side of the battery cell. Preferably, the predetermined distance is one-third or less of the short side of the battery cell. Accordingly, the pressure measured by the surface pressure sensor can accurately represent the internal temperature of the cell stack.

[0024] The circuit board according to one embodiment of the present invention may include the temperature sensor and the surface pressure sensor, and the center of the sensor portion of the temperature sensor and the surface pressure sensor may be positioned within a distance of one-third or less of the short side of the battery cell from the center of the plane of the battery cell.

[0025] The above battery cells may be provided in an even number. At this time, in the cell stack, the number of battery cells stacked on both sides in the width direction of the circuit board may be the same. In this case, the circuit board may be located at the width direction center of the cell stack, i.e., at a location that best represents the temperature and / or internal stress of the cell stack.

[0026] Alternatively, the battery cells may be provided in an odd number. At this time, the circuit board may be stacked on one side of the battery cell in the width direction located at the width direction center of the cell stack. Also, at this time, the temperature sensor may be in contact with the surface of the battery cell on the other width direction side of the circuit board. In this case, the circuit board may be positioned at the width direction center of the cell stack, so as to directly measure the temperature of the battery cell that best represents the temperature of the cell stack, and may be positioned close to the width direction center of the cell stack, so as to be positioned at a portion that best represents the internal stress of the cell stack.

[0027] The cell stack according to one embodiment of the present invention may include an even number of battery cells, and in this case, the circuit board may be arranged so that the same number of battery cells are positioned on both sides in the width direction thereof.

[0028] The above cell stack may include a compressible pad comprising a compressible material and laminated together with the battery cells. The compressible material is formed of a material that is compressible in the width direction, and may absorb the width tolerance of the cell stack or the swelling of the battery cells.

[0029] The compressible pad may be laminated on one widthwise side of the circuit board. At this time, the temperature sensor may be in contact with the surface of the battery cell at the other widthwise side of the circuit board. Alternatively, at this time, a sensor hole is provided at a position corresponding to the temperature sensor in the compressible pad, which opens between the temperature sensor and the battery cell, and the temperature sensor may protrude in one widthwise direction so as to pass through the sensor hole, and may be in contact with the surface of the battery cell at one widthwise side of the circuit board. That is, by providing the sensor hole, the temperature sensor can be in direct contact with the battery cell regardless of which of the widthwise opposite sides of the circuit board the compressible pad is laminated on.

[0030] According to one embodiment of the present invention, a first compressible pad may be laminated on one widthwise side of the circuit board, and a second compressible pad may be laminated on the other widthwise side of the circuit board. At this time, a sensor hole is provided at a position corresponding to the temperature sensor in the first compressible pad, which opens between the temperature sensor and the battery cell, and the temperature sensor may protrude in one widthwise direction so as to pass through the sensor hole, and may come into contact with the surface of the battery cell at one widthwise side of the circuit board.

[0031] According to one embodiment of the present invention, a structure of a battery module including a cell stack is provided in which the compressive pad is stacked on both widthwise sides of the circuit board, so that the widthwise tolerance and swelling are absorbed, while at the same time the temperature sensor can directly contact the surface of the battery cell, so that the temperature of the battery cell can be accurately measured.

[0032] The present invention also provides a battery pack having the battery module built in and a structure of a vehicle having the battery pack built in.

[0033] The above battery modules may be integrated into a battery pack in multiple units to increase capacity and / or voltage. The battery pack may include a venting device capable of discharging gases and flames emitted upward when the battery module ignites to the outside. The battery pack may be incorporated into a vehicle as a power source. The vehicle may include an electric vehicle, a hybrid vehicle, and the like.

[0034] The present invention can provide a structure of a battery module in which high-temperature gas and flames caused by ignition of battery cells can be smoothly discharged upward from the entire upper surface of the cell stack by completely opening the upper surface of the cell stack.

[0035] The present invention also includes a circuit board that can obtain information about electrical information, temperature, internal stress, etc. of a cell stack by being connected to a bus bar, a temperature sensor, and / or a surface pressure sensor, so that the lifespan, status, risk of fire, etc. thereof can be monitored, and by positioning the temperature sensor and the surface pressure sensor at the center of the cell stack, a structure of a battery module can be provided in which the temperature and internal stress of the cell stack can be accurately represented.

[0036] Another advantage of the present invention is that it provides a structure of a battery module in which a temperature sensor can accurately measure the temperature of a battery cell while minimizing the deterioration of structural stability due to tolerance and / or swelling by including a compressible pad.

[0037] In addition, the present invention may have various other effects, which will be described in each embodiment, or the description of effects that can be easily inferred by a person skilled in the art will be omitted.

[0038] Figure 1 shows the structure of a pouch-type battery cell.

[0039] Figures 2 and 3 illustrate the structure of a typical battery module including a circuit board.

[0040] Figures 4 and 5 illustrate the structure of a battery module according to one embodiment of the present invention.

[0041] Figures 6 and 7 illustrate the structure of a circuit board according to one embodiment of the present invention.

[0042] Figures 8 to 10 illustrate the structure of a circuit board on which a compressible pad is laminated according to one embodiment of the present invention.

[0043] Figures 11 and 12 illustrate the structure of a cell stack according to one embodiment of the present invention.

[0044] Figure 13 is an enlarged cross-sectional view showing the arrangement of a temperature sensor according to one embodiment of the present invention.

[0045] Fig. 14 is an enlarged cross-sectional view showing the arrangement of a surface pressure sensor according to one embodiment of the present invention.

[0046] Figures 15 and 16 illustrate a busbar assembly coupled to a cell laminate according to one embodiment of the present invention.

[0047] Figures 17 and 18 illustrate a circuit board according to one embodiment of the present invention connected to a busbar assembly.

[0048] Fig. 19 shows the structure of a cell stack according to one embodiment of the present invention.

[0049] FIGS. 20 and 21 illustrate the structure of a battery pack including a battery module according to one embodiment of the present invention and a vehicle including the battery pack.

[0050] [Explanation of symbols]

[0051] 1: Housing

[0052] 11: U-frame

[0053] 12: Top plate

[0054] 121: Venting Hall

[0055] 122: Circuit board cover

[0056] 13: End plate

[0057] 2: Cell stack

[0058] 21: Battery cell

[0059] 210: Pouch

[0060] 211: Sealing Department

[0061] 212: Terrace Department

[0062] 213: Electrode lead

[0063] 22: Compressible pad

[0064] 221: First compressible pad

[0065] 223: Sensor Hall

[0066] 222: Second compressible pad

[0067] 23: Circuit board

[0068] 230: Substrate

[0069] 231: First connector

[0070] 232: Second connector

[0071] 233: Temperature sensor

[0072] 234: Surface pressure sensor

[0073] 3: Busbar assembly

[0074] 31: Busbar frame

[0075] 311: Slit

[0076] 32: Bus bar

[0077] 321: Terminal

[0078] M: Battery module

[0079] P: Battery pack

[0080] V: Car

[0081] X: longitudinal direction (front-back)

[0082] Y: width direction (left and right)

[0083] Z: Height direction (up / down direction)

[0084] The above-described objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily practice the technical idea of ​​the present invention. In describing the present invention, if it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the gist of the present invention, a detailed description thereof will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0085] Although the terms "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are used solely to distinguish one component from another, and unless otherwise specified, a "first" component may also be a "second" component.

[0086] Throughout the specification, unless otherwise specifically stated, each element may be singular or plural.

[0087] Hereinafter, the phrase "any configuration is placed on (or below)" a component or "on (or below)" a component may mean that any configuration is placed in contact with the upper surface (or lower surface) of said component, and that other configurations may be interposed between said component and any configuration placed on (or below) said component.

[0088] Additionally, when it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the components may be directly connected or connected to one another, but that other components may also be "interposed" between the components, or that each component may be "connected," "coupled," or "connected" through another component.

[0089] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not necessarily be construed to include all of the components or steps described in the specification, and should be construed to mean that some of the components or steps may not be included, or that additional components or steps may be included.

[0090] Throughout the specification, when we refer to "A and / or B", this means A, B, or A and B, unless otherwise stated, and when we refer to "C to D", this means C or more and D or less, unless otherwise stated.

[0091] The present invention provides a structure of a battery module including a plurality of battery cells that are laminated in the width direction to form a cell laminate, wherein the cell laminate includes a circuit board laminated in the width direction together with the battery cells, and the circuit board includes at least one of a temperature sensor in contact with a surface of the battery cell and a surface pressure sensor that measures internal stress in the width direction of the cell laminate.

[0092] Hereinafter, a preferred embodiment of the present invention will be described with reference to the attached drawings.

[0093] [Pouch-type battery cell structure]

[0094] Hereinafter, with reference to FIG. 1, the structure of a pouch-type battery cell included in a battery module according to one embodiment of the present invention will be described.

[0095] Figure 1 illustrates the structure of a pouch-type battery cell. Referring to this, the battery cell (21) may include an electrode assembly and a pouch (210) that accommodates the electrode assembly.

[0096] According to one embodiment of the present invention, the pouch (210) may be folded in half to enclose the electrode assembly and seal three sides except for the folded side. At this time, the pouch (210) may include a sealing portion (211) formed at an end opposite the folded side and a terrace portion (212) formed at both ends in the longitudinal direction thereof.

[0097] The above sealing portion (211) can be folded once or multiple times, and can be sealed by additionally attaching tape.

[0098] The electrode assembly may include a pair of electrode leads (213) that connect the electrode assembly to the outside. The electrode leads (213) may protrude from both longitudinal ends of the electrode assembly. The electrode leads (213) may protrude to the outside of the pouch (210) through the terrace portion (212).

[0099] [Battery module structure]

[0100] Hereinafter, with reference to FIGS. 4 and 5, the structure of another battery module according to an embodiment of the present invention will be described.

[0101] Figures 4 and 5 illustrate the structure of a battery module according to one embodiment of the present invention. Referring to these drawings, a battery module (M) according to one embodiment of the present invention may include a cell stack (2) in which a plurality of battery cells (21) are stacked in the width direction, a bus bar assembly (3) connected to one end of the cell stack (2) in the length direction, and a housing (1) for accommodating them.

[0102] The housing (1) according to one embodiment of the present invention may include a U-frame (11) open at the top and front and rear, a top plate (12) covering the top of the U-frame (11), and a pair of end plates (13) covering the front and rear of the U-frame (11).

[0103] The top plate (12) may include a venting hole (121) so that high-temperature gas and flames can be discharged upward when the battery cell (21) ignites. It is preferable that the venting hole (121) be distributed throughout the entire section of the top plate (12). In particular, as will be described later, according to one embodiment of the present invention, the venting hole (121) may also be provided along the center of the width direction of the top plate (12).

[0104] [Structure of circuit board and cell stack]

[0105] Hereinafter, with reference to FIGS. 6 to 19, the structure of a circuit board and a cell stack according to one embodiment of the present invention will be described in detail.

[0106] The above cell stack (2) can be formed by stacking a plurality of battery cells (21) in the width direction. The above cell stack (2) can also include a circuit board (23) that is stacked in the width direction together with the battery cells (21).

[0107] Figures 6 and 7 illustrate the structure of a circuit board according to one embodiment of the present invention. Referring to these drawings, the circuit board (23) may include a substrate portion (230) and a first connection portion (231) connected to the substrate portion (230).

[0108] The above substrate portion (230) may include a plurality of elements so that the circuit board (23) can measure information about the voltage, current, current amount, charge amount, temperature, internal pressure, lifespan, etc. of the cell stack (2) and store, transmit, and / or display the same.

[0109] The first connecting portion (231) can connect the substrate portion (230) to the cell stack (2). The substrate portion (230) can obtain various information regarding the state of the cell stack (2) through the first connecting portion (231).

[0110] The circuit board (23) may include a temperature sensor (233). The temperature sensor (233) according to one embodiment of the present invention may be connected to the first connection portion (231), but the position at which the temperature sensor (233) is connected to the circuit board (23) is not limited thereto.

[0111] The temperature sensor (233) is preferably positioned so as to be in contact with the battery cell (21) so as to measure the temperature of the cell stack (2). To this end, the temperature sensor (233) may have a shape that protrudes a predetermined distance in one direction in the width direction.

[0112] According to one embodiment of the present invention, the temperature sensor (233) may be arranged to contact at least one width-wise side surface of the battery cell (21), and preferably may be provided at a planar center portion of the width-wise side surface of the battery cell (21). In other words, the planar center of the portion of the temperature sensor (233) that contacts the battery cell (21) may be located within a predetermined distance from the center of the width-wise side surface of the battery cell (21). The predetermined distance is preferably one-third or less of the short side of the battery cell (21).

[0113] According to one embodiment of the present invention, the temperature sensor (233) may include a thermally variable resistor. The thermally variable resistor may be configured to change its resistance according to a change in the temperature of the cell stack (2), and thus transmit information about the temperature of the cell stack (2) to the substrate (230). However, the temperature sensor (233) is not limited to including the thermally variable resistor, and may have any structure as long as it is configured to measure the temperature of the cell stack (2) and transmit information about the temperature to the substrate (230).

[0114] The circuit board (23) may include a surface pressure sensor (234). The surface pressure sensor (234) according to one embodiment of the present invention may be arranged on one side of the width direction of the board portion (230) and connected to the board portion (230), but the position of the surface pressure sensor (234) and the position at which it is connected to the circuit board (23) are not limited thereto.

[0115] The surface pressure sensor (234) is preferably interposed in the width direction inside the cell stack (2) so as to measure the width direction stress of the cell stack (2), i.e., the width direction pressure applied to the battery cells (21) included in the cell stack (2). The surface pressure sensor (234) and the battery cells (21) do not need to be in direct contact with each other. For example, as in one embodiment of the present invention, the surface pressure sensor (234) may be positioned inside the cell stack (2) with the substrate (230) or a compressive pad to be described later interposed between the surface pressure sensor and the battery cells (21).

[0116] According to one embodiment of the present invention, the surface pressure sensor (234) may preferably be provided at the center of the plane of the widthwise side of the battery cell (21). In other words, the center of the plane of the surface pressure sensor (234) may be located within a predetermined distance from the center of the widthwise side of the battery cell (21). The predetermined distance is preferably one-third or less of the short side of the battery cell (21).

[0117] According to one embodiment of the present invention, the surface pressure sensor (234) may include a piezoelectric sensor. The piezoelectric sensor may be configured to change the potential difference between both ends in a predetermined direction according to pressure in the predetermined direction, and thus transmit information on the internal stress in the width direction of the cell stack (2) to the substrate (230). However, the surface pressure sensor (234) is not limited to including the piezoelectric sensor, and may have any structure as long as it is configured to measure the internal stress of the cell stack (2) and transmit information on the same to the substrate (230).

[0118] Figures 8 to 10 illustrate the structure of a circuit board on which a compressible pad is laminated according to one embodiment of the present invention. Referring to these drawings, the cell laminate (2) may include a compressible pad (22) laminated in the width direction together with the battery cell (21) and the circuit board (23).

[0119] The above compressible pad (22) may be made of a compressible material and may be capable of absorbing the width tolerance of the cell stack (2) or the swelling of the battery cell (21).

[0120] The above compressive pad (22) may be laminated on one or both sides of the width direction of the circuit board (23).

[0121] The above compressible pad (22) may include a first compressible pad (221) laminated on one side in the width direction of the circuit board (23). At this time, the circuit board (23) may include the temperature sensor (233) protruding on one side in the width direction thereof, and the first compressible pad (221) may be provided with a sensor hole (223) that is opened so that the temperature sensor (233) can come into contact with the battery cell (21) on one side in the width direction thereof. Alternatively, the circuit board (23) may include the temperature sensor (233) coming into contact with the battery cell (21) on the other side in the width direction thereof.

[0122] The above compressible pad (22) may include a second compressible pad (222) laminated on the other side in the width direction of the circuit board (23).

[0123] According to one embodiment of the present invention, the circuit board (23) may include the temperature sensor (233) protruding in one width direction thereof, and the compressible pad (22) may include the first compressible pad (221) laminated on one width direction side of the circuit board (23), and the second compressible pad (222) laminated on the other width direction side of the circuit board (23), and the first compressible pad (221) may be provided with the sensor hole (223) that is open so that the temperature sensor (233) can come into contact with the battery cell (21) in one width direction thereof.

[0124] Figures 11 and 12 illustrate the structure of a cell stack according to one embodiment of the present invention. Referring to these drawings, the circuit board (23) can be stacked together with the battery cell (21) to form the cell stack (2). At this time, the compressible pad (22) can also be stacked together with the battery cell (21) to form the cell stack (2).

[0125] The above cell stack (2) can be formed by stacking a plurality of cell banks with the compressible pad (22) interposed between them. The above cell bank can be formed by stacking a plurality of the above battery cells (21).

[0126] The above circuit board (23) can be laminated together with the battery cell (21) to form the cell laminate (2).

[0127] FIG. 13 is an enlarged cross-sectional view showing the arrangement of a temperature sensor according to one embodiment of the present invention, and FIG. 14 is an enlarged cross-sectional view showing the arrangement of a surface pressure sensor according to one embodiment of the present invention.

[0128] Referring to FIG. 13, the circuit board (23) according to one embodiment of the present invention can form an assembly in which the first compressible pad (221) is laminated on one widthwise side thereof and the second compressible pad (222) is laminated on the other widthwise side thereof, and the temperature sensor (233) can measure the temperature of the battery cell (21) by coming into contact with the surface of the battery cell (21) laminated on one widthwise side of the circuit board (23) through the sensor hole (223) provided in the first compressible pad (221). It is preferable that the degree to which the temperature sensor (233) protrudes on one widthwise side is greater than the thickness of the first compressible pad (221). In this case, the temperature sensor (233) is elastically deformed in the other width direction as the first compressible pad (221) is in close contact with the battery cell (21), and thus receives an elastic restoring force in one width direction, thereby allowing the temperature sensor (233) to be in closer contact with the battery cell (21).

[0129] Also, referring to FIG. 14, the surface pressure sensor (234) is interposed between the first compressible pad (221) and the second compressible pad (222) to measure the widthwise internal stress thereof. Since the internal stress of the cell stack (2) is constant along the widthwise direction, the position of the surface pressure sensor (234) is irrelevant as long as it is on the widthwise inner side of the cell stack (2).

[0130] Referring back to FIGS. 11 and 12, the cell stack (2) may include an even number of battery cells (21). At this time, it is preferable that the number of battery cells (21) stacked on both sides in the width direction of the circuit board (23) is the same. In other words, the circuit board (23) may be interposed between two sets of battery cells (21) having the same number. In this case, the circuit board (23) is positioned at the center of the width direction of the cell stack (2), so that the temperature and / or pressure measured by the temperature sensor (233) and / or the surface pressure sensor (234) can more accurately represent the temperature and / or internal stress of the cell stack (2).

[0131] Alternatively, the cell stack (2) may include an odd number of the battery cells (21). At this time, the circuit board may be provided on one widthwise side of the battery cell (21) located at the widthwise center of the cell stack (2), and the temperature sensor (233) may be in contact with the battery cell (21) on the other widthwise side of the circuit board (23). In this case, the temperature sensor (233) may measure the temperature of the battery cell (21) closest to the widthwise center of the cell stack (2).

[0132] According to one embodiment of the present invention, an assembly including the circuit board (23) and the first compressible pad (221) and the second compressible pad (222) laminated on both sides in the width direction thereof can be laminated together with the battery cells (21) with the same number of battery cells (21) positioned on both sides in the width direction thereof.

[0133] Figures 15 and 16 illustrate a busbar assembly coupled to a cell stack according to one embodiment of the present invention. Referring to these drawings, the busbar assembly (3) may be connected to one longitudinal end of the cell stack (2). The busbar assembly (3) may include a busbar frame (31) covering the front surface of the cell stack (2) and a busbar (32) to which the electrode lead (213) is connected.

[0134] The above bus bar frame (31) may include a slit (311) through which the electrode lead (213) passes in the longitudinal direction. At one longitudinal end of the cell stack (2), the electrode lead (213) may pass through the slit (311) and be connected to the bus bar (32).

[0135] The above bus bar (32) may be provided on the front side of the bus bar frame (31). The bus bar (32) may include a part not included in the bus bar assembly (3), and may also be provided on the other longitudinal end of the cell stack (2). The bus bar (32) may be electrically connected to the electrode lead (213), thereby connecting the battery cells (21) in series or in parallel.

[0136] At least one of the bus bars (32) may be provided with a pair of terminals (321) for electrically connecting the cell stack (2) to the outside. Referring again to FIGS. 4 and 5, the terminals (321) may be exposed to the outside through terminal exposure holes provided in the end plate (13). Since the battery module (M) may be connected to other battery modules in series or parallel through the terminals (321) to form a battery pack, it is important that high-temperature gas and flames caused by ignition of the battery cell (21) are not discharged to the front of the battery module (M). As in one embodiment of the present invention, since the circuit board (23) is provided within the cell stack (2), the venting holes (121) may be provided in the entire area of ​​the top plate (12), so that the gas and flames from the battery cell (21) may be discharged more smoothly upward, and the gas and flames discharged forward may be reduced.

[0137] Figures 17 and 18 illustrate a circuit board according to an embodiment of the present invention connected to a busbar assembly. Referring to these drawings, the circuit board (23) may include the first connecting portion (231) and the second connecting portion (232) connected to the busbar (32). The second connecting portion (232) according to an embodiment of the present invention may be fixed to the busbar frame (31). However, the second connecting portion (232) only needs to connect the first connecting portion (231) and the busbar (32), and its structure or position is not important. Through the first connecting portion (231) and the second connecting portion (232), the circuit board (230) may be connected to the busbar (32), and information related to the electrical characteristics of the cell stack (2) may be obtained.

[0138] Fig. 19 shows the structure of a cell stack according to one embodiment of the present invention. Referring to this, the cell stack (2) according to one embodiment of the present invention can be formed by stacking the battery cell (21), the compressible pad (22), and the circuit board (23) in the width direction, and the bus bar assembly (3) can be connected to one end in the length direction thereof. The circuit board (23) is provided at the width direction center of the cell stack (2) and includes the temperature sensor (233) and / or the surface pressure sensor (234), thereby being able to measure the temperature and width direction internal stress of the cell stack (2). In addition, the circuit board (23) is connected to the bus bar (32) connected to the electrode lead (213) through the first connection portion (231) and the second connection portion (232), thereby obtaining electrical information about the cell stack (2). At this time, since the circuit board (23) does not cover the upper surface of the cell stack (2), gas and flame can easily be discharged upward from any point on the plane of the cell stack (2).

[0139] [Battery Packs and Automobiles]

[0140] Hereinafter, with reference to FIGS. 20 and 21, the structure of a battery pack and a vehicle according to one embodiment of the present invention will be described.

[0141] FIGS. 20 and 21 illustrate the structure of a battery pack including a battery module according to one embodiment of the present invention and a vehicle including the battery pack. Referring to these drawings, a plurality of battery modules (M) may be integrated to form a battery pack (P) in order to increase the capacity and / or voltage. The battery pack (P) may include a venting device capable of discharging gases and flames discharged upward when the battery module (M) ignites to the outside. The battery pack (P) may be incorporated into a vehicle (V) as a power source. The vehicle (V) may include an electric vehicle, a hybrid vehicle, etc.

[0142]

[0143] It should be understood that the above-described embodiments are illustrative in all respects and not restrictive, and the scope of the present invention will be determined by the claims that follow, rather than by the detailed description set forth above. Furthermore, the meaning and scope of the claims that follow, as well as all possible modifications and variations derived from their equivalent concepts, should be construed as encompassing the scope of the present invention.

[0144] Although the present invention has been described with reference to the drawings exemplified above, it is to be understood that the present invention is not limited to the embodiments and drawings disclosed herein, and that various modifications may be made by those skilled in the art within the scope of the technical idea of ​​the present invention. Furthermore, even if the operational effects according to the configuration of the present invention have not been explicitly described while describing the embodiments of the present invention, it is natural that the effects predictable by the corresponding configuration should also be acknowledged.

Claims

1. In a battery module including a circuit board and a cell stack formed by stacking a plurality of battery cells in the width direction, The circuit board includes a temperature sensor in contact with the surface of the battery cell, A battery module in which the circuit board is positioned so as to be in contact with a battery cell located at the widthwise center of the cell stack or is positioned so as to be located at the widthwise center of the cell stack.

2. In claim 1, The above temperature sensor is a battery module including a thermovariable resistor (thermistor).

3. In claim 1, The battery module wherein the temperature sensor is provided at the central portion of the plane of the circuit board.

4. In claim 1, The above battery cells are provided in an even number, A battery module in which the number of battery cells laminated on both sides of the width direction of the circuit board in the above cell stack is the same.

5. In claim 1, The above battery cells are provided in odd numbers, The circuit board is laminated on one side of the width direction of the battery cell located at the width direction center of the cell stack, The above temperature sensor is in contact with the surface of the battery cell on the other side of the width direction of the circuit board, the battery module.

6. In claim 1, A battery module, wherein the cell stack includes a compressible material and a compressible pad that is stacked together with the battery cells.

7. In claim 6, The compressive pad is laminated on one side of the width direction of the circuit board, The above temperature sensor is in contact with the surface of the battery cell on the other side of the width direction of the circuit board, the battery module.

8. In claim 6, The compressive pad is laminated on one side of the width direction of the circuit board, In the above compressible pad, a sensor hole is provided at a position corresponding to the temperature sensor to open between the temperature sensor and the battery cell, A battery module in which the temperature sensor protrudes in one width direction to pass through the sensor hole and comes into contact with the surface of the battery cell on one width direction side of the circuit board.

9. In claim 6, A predetermined first compressive pad is laminated on one side of the width direction of the circuit board, A second compressive pad is laminated on the other side of the width direction of the circuit board, In the first compressive pad, a sensor hole is provided at a position corresponding to the temperature sensor to open between the temperature sensor and the battery cell, A battery module in which the temperature sensor protrudes in one width direction to pass through the sensor hole and comes into contact with the surface of the battery cell on one width direction side of the circuit board.

10. In claim 1, A battery module, wherein the circuit board includes a surface pressure sensor for measuring internal stress in the width direction of the cell stack.

11. In claim 10, A battery module in which the above-mentioned pressure sensor includes a piezoelectric sensor.

12. In claim 10, A battery module in which the above-mentioned surface pressure sensor is provided at the central portion of the plane of the circuit board.

13. A battery module including a circuit board, a compressible pad, and a cell stack formed by stacking a plurality of battery cells in the width direction, The circuit board includes a temperature sensor in contact with the surface of the battery cell, A battery module, wherein the above compressible pad has a sensor hole through which the temperature sensor passes and comes into contact with the battery cell.

14. In claim 13, The above temperature sensor is a battery module including a thermovariable resistor (thermistor).

15. In claim 13, The battery module wherein the temperature sensor is provided at the central portion of the plane of the circuit board.

16. In claim 13, The above battery cells are provided in an even number, A battery module in which the number of battery cells laminated on both sides of the width direction of the circuit board in the above cell stack is the same.

17. In claim 13, The above battery cells are provided in odd numbers, The circuit board is laminated on one side of the width direction of the battery cell located at the width direction center of the cell stack, The above temperature sensor is in contact with the surface of the battery cell on the other side of the width direction of the circuit board, the battery module.

18. In claim 13, The compressive pad is laminated on one side of the width direction of the circuit board, The above temperature sensor is in contact with the surface of the battery cell on the other side of the width direction of the circuit board, the battery module.

19. In claim 13, The above compressible pad is laminated on one side of the width direction of the circuit board, A battery module in which the temperature sensor protrudes in one width direction to pass through the sensor hole and comes into contact with the surface of the battery cell on one width direction side of the circuit board.

20. In claim 13, The above compressible pad: A first compressive pad provided on one side of the width direction of the circuit board; and Including a second compressive pad provided on the other side in the width direction of the circuit board, The above sensor hole is provided in the first compressible pad, A battery module in which the temperature sensor protrudes in one width direction to pass through the sensor hole and comes into contact with the surface of the battery cell on one width direction side of the circuit board.

21. In claim 13, A battery module, wherein the circuit board includes a surface pressure sensor for measuring internal stress in the width direction of the cell stack.

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