Battery module

Abstract

To provide a battery module capable of suppressing spread of abnormal phenomena, such as high temperature, gas, and sparks, generated in some battery cells to other battery cells in the vicinity.SOLUTION: The present disclosure relates to a battery module and provides a battery module which includes: a plurality of battery cells arranged in a first direction; and an insulating sheet formed of an insulating material and including a middle portion covering a first surface of the plurality battery cells, the middle portion being formed with at least one cut line extending in a second direction.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a battery module. [Background technology]

[0002] In general, the demand for portable electronic products such as notebook computers, video cameras, mobile phones, etc. is rapidly increasing, and the commercialization of robots, electric vehicles, etc. is becoming widespread. As a result, research into high-performance secondary batteries that can be repeatedly charged and discharged is being actively conducted.

[0003] Secondary batteries are widely used for driving and energy storage not only in small devices such as portable electronic devices but also in medium-sized and large devices such as electric vehicles and energy storage systems (ESS). In particular, in the case of medium-sized and large devices, a battery module is formed in which a number of battery cells are electrically connected to each other to improve the battery output and / or capacity.

[0004] When the battery module is charged or discharged, or when an external impact is applied to the battery module, the temperature of some of the battery cells in the battery module may rise suddenly, causing them to swell and generate sparks. Due to the structure in which many battery cells are densely packed together, high temperatures, gases, and sparks generated in some battery cells may spread rapidly to other surrounding battery cells, easily developing into a large fire. Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a battery module that suppresses the diffusion of abnormal phenomena, such as high temperature, gas, and sparks, generated in some battery cells to other surrounding battery cells.

[0006] However, the technical problems that the present invention aims to solve are not limited to the problems mentioned above, and other problems not mentioned can be clearly understood by those skilled in the art from the following description of the invention. [Means for solving the problem]

[0007] In order to solve the above technical problem, a battery module according to one embodiment of the present invention includes: a plurality of battery cells arranged in a first direction; and an insulating sheet formed of an insulating material, including a central portion covering first surfaces of the plurality of battery cells, and having at least one cut line extending in a second direction formed in the central portion.

[0008] The cut line may include a plurality of through holes that penetrate the central portion in a thickness direction and are arranged to be spaced apart from one another along a straight line extending in the second direction.

[0009] The cut line may be positioned to overlap a boundary line between a pair of adjacent battery cells among the plurality of battery cells.

[0010] A terminal of the battery cell may be formed on the first surface of the battery cell, and a terminal hole may be formed penetrating the central portion in a thickness direction to expose the terminal at the central portion.

[0011] A vent through which gas generated inside the battery cell is released may be formed on the first surface of the battery cell, and a vent hole may be formed penetrating the central portion in a thickness direction to expose the vent to the central portion.

[0012] The battery module may further include a holder that covers the central portion to prevent the central portion from lifting up toward the first side.

[0013] Both side ends of the holder in the second direction may be in close contact with the central portion.

[0014] The insulating sheet may further include a pair of side wall portions formed of an insulating material, connected to both end portions of the central portion in the second direction and extending downward so as to cover both side surfaces of the plurality of battery cells in the second direction.

[0015] The pair of side wall portions may be fixed to both side surfaces of the battery cell.

[0016] At least one separation slit may be formed in each of the pair of side walls, penetrating the side walls in a thickness direction and extending in a third direction.

[0017] The separation slit may be positioned to overlap a boundary line between a pair of adjacent battery cells among the plurality of battery cells.

[0018] The cutting line and the separation slit may be connected at both side ends of the central portion.

[0019] The separation slit may be open at a lower end of the side wall portion.

[0020] The separation slits may extend from the opposite side ends of the central portion to lower ends of the side walls.

[0021] The battery module may further include a pair of side plates arranged to face the pair of side wall portions and cover the pair of side wall portions; and a holder covering the central portion and having both side ends in the second direction coupled to the pair of side plates. Effect of the Invention

[0022] According to an embodiment of the present invention, even if an abnormal phenomenon such as high temperature heat generation, gas generation, volume expansion, or spark generation occurs in some battery cells among a plurality of battery cells included in a battery module, the insulating sheet prevents the abnormal phenomenon from spreading to other surrounding battery cells, thereby slowing the spread and propagation of fire or explosion and reducing loss of life and property.

[0023] According to an embodiment of the present invention, when an abnormality occurs in some of the battery cells included in a battery module, only the portion of the insulating sheet covering the battery cell in which the abnormality occurs can be separated from the other portions along the cutting line, and the insulating sheet covering the other battery cells in which no abnormality occurs can be maintained in a state of covering the battery cells, thereby more effectively preventing the spread of the abnormality to other surrounding battery cells.

[0024] According to an embodiment of the battery module of the present invention in which the insulating sheet includes a side wall portion, the spread of heat and sparks through the side surfaces of the battery cells is suppressed by the side wall portion, thereby further delaying the propagation and spread of fires and explosions.

[0025] However, the effects obtained through the present invention are not limited to the effects described above, and other technical effects not mentioned herein will be clearly understood by those skilled in the art from the following description of the invention. [Brief description of the drawings]

[0026] [Figure 1] 1 is a perspective view of a battery module according to a first embodiment of the present invention; [Diagram 2] 1 is an exploded perspective view of a battery module according to a first embodiment of the present invention; [Diagram 3] FIG. 3 is a cross-sectional view taken along the line III-III in FIG. [Figure 4] 4 is an enlarged view of part IV in FIG. 3. [Diagram 5] 4 is an enlarged view of a portion V in FIG. 3. [Figure 6] FIG. 3 is a perspective view showing a plurality of battery modules of FIG. 2. [Figure 7] 3 is a perspective view of the insulating sheet of FIG. 2, showing a portion thereof being separated and lifted along a cut line; [Figure 8]FIG. 11 is a perspective view of a battery module according to a second embodiment of the present invention, showing that the holder is disassembled upward so as to be separated from the front frame, the rear frame, and the pair of side plates. [Figure 9] FIG. 11 is an exploded perspective view of a battery module according to a second embodiment of the present invention. [Figure 10] FIG. 9 is a cross-sectional view taken along the line XX in FIG. 8, showing that the holder is coupled to the front frame, the rear frame, and a pair of side plates. [Figure 11] 11 is an enlarged view of a portion XI in FIG. 10. [Figure 12] 12 is an enlarged view of part XII in FIG. 10. [Figure 13] 10 is a perspective view of the insulating sheet of FIG. 9, showing a portion thereof being separated and lifted along a cut line. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in the present specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as being consistent with the technical ideas of the present invention, based on the principle that the inventor can appropriately define the concepts of terms to best describe his / her invention. Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely some of the most preferred embodiments of the present invention, and do not fully represent the technical ideas of the present invention, and therefore there may be various equivalents and modifications that can replace them at the time of filing this application. In addition, when used in this specification, "comprise, include" and / or "comprising, including" specify the presence of the mentioned shapes, numbers, steps, operations, members, elements, and / or groups thereof, and do not exclude the presence or addition of one or more other shapes, numbers, operations, members, elements, and / or groups. In addition, when describing an embodiment of the present invention, "may" and "may be" may include "one or more embodiments of the present invention."

[0028] In order to facilitate understanding of the invention, the accompanying drawings are not drawn to scale, and the dimensions of some components may be exaggerated. In addition, the same reference numerals may be used to refer to the same components in different embodiments.

[0029] A statement that two objects are "identical" means that they are "substantially identical." Thus, substantially identical may include cases where there is a deviation that is considered to be a low level in the art, for example, within 5%. Also, a statement that a parameter is uniform in a given region may mean that the parameter is uniform on average.

[0030] Even if the terms "first", "second", etc. are used to describe various components, it is understood that these components are not limited by these terms. These terms are merely used to distinguish one component from another, and it is understood that a first component can also be a second component unless otherwise specified.

[0031] Throughout the specification, unless specifically stated to the contrary, each element may be singular or plural.

[0032] When an arbitrary structure is disposed on the "top (or bottom)" of a component, or on (above) (below) of a component, it may mean that the arbitrary structure is disposed in contact with the upper surface (or lower surface) of the component, but also that another structure may be interposed between the component and the arbitrary structure disposed on (or below) the component.

[0033] In addition, when a description is made that a certain component is "coupled," "coupled," or "connected" to another component, it should be understood that the components may be directly coupled or connected to each other, but there may also be another component "intervening" between each component, or each component may be "coupled," "coupled," or "connected" through another component. In addition, when a part is electrically coupled to another part, this includes not only the case where the part is directly coupled, but also the case where the part is electrically coupled to another part through another element in between.

[0034] Throughout the specification, "A and / or B" means A, B, or A and B, unless specifically stated to the contrary. That is, "and / or" includes all or any combination of the listed items. "C through D" means at least C and at most D, unless specifically stated to the contrary.

[0035] The battery pack includes at least one battery module and a pack housing having an accommodation space for accommodating the at least one battery module.

[0036] The battery module may include a plurality of battery cells and a module housing. The battery cells may be accommodated in the module housing in a stacked form. The battery cells may include an anode lead and a cathode lead. The battery cells may be circular, rectangular, or pouch type battery cells depending on the form of the battery.

[0037] The battery pack may have a cell stack instead of the battery module, which may be accommodated in an accommodating space of a pack housing or in an accommodating space partitioned by a frame, a partition, or the like.

[0038] The battery cells generate a large amount of heat during charging / discharging. The generated heat accumulates in the battery cells and accelerates deterioration of the battery cells. Therefore, the battery pack further includes a cooling member to suppress deterioration of the battery cells. The cooling member is provided at a lower portion of the accommodation space in which the battery cells are provided, but is not limited thereto, and may be provided at an upper portion or a side portion of the battery pack.

[0039] The battery cell may discharge exhaust gas generated in the battery cell during an abnormal operating condition, also known as a thermal runaway or a thermal event, to the outside of the battery cell. The battery pack or the battery module may include an exhaust port for discharging exhaust gas to prevent the exhaust gas from damaging the battery pack or the battery module.

[0040] The battery pack may include a battery and a battery management system (BMS) for managing the battery. The battery management system may include a detection device, a balancing device, and a control device. The battery module may include a plurality of cells connected in series or parallel to each other. The battery modules may be connected in series or parallel to each other.

[0041] The detection device can sense the state of the battery (voltage, current, temperature, etc.) and detect state information representing the state of the battery. The detection device can detect the voltage of each cell or each battery module constituting the battery. The detection device can also detect the current flowing through each battery module constituting a battery module or a battery pack. The detection device can also detect the cell and / or module and / or ambient temperature at at least one point of the battery.

[0042] The balancing device can perform a balancing operation of the battery modules and / or cells that constitute the battery. The control device can receive state information (voltage, current, temperature, etc.) of the battery module from the detection device. The control device can monitor and calculate the state (voltage, current, temperature, state of charge (SOC), state of health (SOH), etc.) of the battery module based on the state information received from the detection device. The control device can also perform control functions (e.g., temperature control, balancing control, charge / discharge control, etc.), protection functions (e.g., over-discharge, over-charge, over-current prevention, short circuit, fire extinguishing function, etc.), etc. based on the state monitoring result. The control device can also perform wired or wireless communication functions with external devices of the battery pack (e.g., a higher-level controller, a vehicle, a charger, a PCS, etc.).

[0043] The control device can also control the charging / discharging and protection operations of the battery, and for this purpose, the control device can include a charging / discharging control unit, a balancing control unit, and a protection unit.

[0044] The battery management system is a system that monitors the battery status and performs diagnostic, control, communication and protection functions. It also calculates the charge / discharge status, calculates the battery's life or state of health (SOH), cuts off battery power (relay control) as necessary, controls thermal management (cooling, heating, etc.), performs high voltage interlock functions, and can detect and calculate insulation and short circuit conditions.

[0045] A relay can be a mechanical contactor that is turned on and off by the magnetic force of a coil, or it can be a semiconductor switch such as a Metal Oxide Semiconductor Field Effect Transistor (MOSFET).

[0046] The relay control may be configured with one or more relays and a precharge relay at the positive and negative terminals, respectively, depending on the function of cutting off the power supply from the battery when a problem occurs in the vehicle and battery system.

[0047] The precharge control may have a function of operating a precharge relay and connecting it to a precharge resistor before connecting the main relay when starting the vehicle in order to prevent the inrush current from being drawn in, since there is a risk of an inrush current being generated in the high voltage capacitor on the inverter input side when a battery load is connected.

[0048] The high voltage interlock is a circuit that uses a small signal to detect whether all high voltage components are connected to the entire automotive system, and can have the function of forcibly opening a relay if an open circuit occurs at any point on the entire loop.

[0049] FIG. 1 is a perspective view of a battery module according to a first embodiment of the present invention, FIG. 2 is an exploded perspective view of a battery module according to the first embodiment of the present invention, FIG. 3 is a cross-sectional view of FIG. 1 cut along III-III, FIG. 4 is an enlarged view of portion IV of FIG. 3, FIG. 5 is an enlarged view of portion V of FIG. 3, FIG. 6 is a perspective view of multiple battery modules of FIG. 2, and FIG. 7 is a perspective view of an insulating sheet of FIG. 2, showing a portion separated and lifted along the cut line.

[0050] 1 to 7, a battery module 100A according to a first embodiment of the present invention includes a plurality of battery cells 101 and an insulating sheet 160A. The battery cells 101 function as unit structures for storing and supplying power in the battery module 100A.

[0051] Although not shown in the drawing, the battery cell 101 can be exemplified as a prismatic secondary battery that has an electrode assembly (not shown) therein in which a positive electrode plate (not shown) and a negative electrode plate (not shown) are arranged on either side of a separator (not shown) and that can charge and discharge a preset amount of power.

[0052] The battery cell 101 may include a cell body 102, a pair of terminals 107, and a vent 106. The cell body 102 may have a rectangular parallelepiped shape with a thickness in a first direction smaller than a height in a third direction and a width in a second direction. The multiple battery cells 101 may be arranged parallel to the thickness direction, i.e., in a line in the first direction.

[0053] In the illustrated embodiments of the present invention, the first direction is the front-rear direction, the second direction is the left-right direction, and the third direction is the up-down direction, but the present invention is not limited thereto and various modifications are possible.

[0054] One of the pair of terminals 107 may be an anode terminal and the other may be a cathode terminal. The pair of terminals 107 may protrude from a first surface 103 of the cell body 102. In the illustrated embodiment of the present invention, the first surface is exemplified as the top surface of the cell body 102. However, the present invention is not limited thereto, and various modifications may be made.

[0055] The pair of terminals 107 may be spaced apart from each other and disposed one on each side in a second direction perpendicular to the first and third directions.

[0056] The vent 106 may be provided between a pair of terminals 107 on the first surface 103 of the cell body 102. Gas generated inside the battery cell 101, i.e., inside the cell body 102, may be released to the outside through the vent 106. Although not shown in the drawings, the battery cell 101 may further include a cap plate that closes the first surface 103 to prevent substances such as an electrode assembly and an electrolyte contained inside the cell body 102 from leaking out.

[0057] The insulating sheet 160A is a plate-like member made of an insulating material. The insulating sheet 160A includes a central portion 162 that covers the first surfaces 103 of the plurality of battery cells 101 arranged in a first direction. The central portion 162 may have a plurality of cut lines 170 formed therein and extending in a second direction.

[0058] The multiple cut lines 170 can be positioned so as to overlap with boundary lines 112 between adjacent pairs of battery cells 101 among the multiple battery cells 101. The boundary line between adjacent pairs of battery cells 101 can be divided into a first surface boundary line 112 seen from above the multiple battery cells 101, a second surface boundary line 113 seen from the side of the multiple battery cells 101, and a third surface boundary line (not shown) seen from below the multiple battery cells 101.

[0059] In the illustrated embodiment of the present invention, the second surface is described as the left or right surface of the cell body 102, and the third surface is described as the bottom surface of the cell body 102. However, the present invention is not limited thereto, and various modifications are possible.

[0060] Specifically, among the first surface boundary line 112, the second surface boundary line 113, and the third surface boundary line, the cut line 170 formed in the central portion 162 may be positioned to vertically overlap the first surface boundary line 112. The number of cut lines 170 formed in the central portion 162 may be one less than the number of the plurality of battery cells 101 arranged in the first direction.

[0061] Each cut line 170 may include a plurality of through holes 172 that penetrate the central portion 162 in the thickness direction and are arranged to be spaced apart from each other along a straight line extending in a second direction perpendicular to the first direction and the third direction. The length of the through holes 172 in the second direction may be longer than the interval between adjacent pairs of the through holes 172.

[0062] The insulating sheet 160A may be formed with a plurality of terminal holes 165 and a plurality of vent holes 167. The plurality of terminal holes 165 may be formed penetrating the central portion 162 in a thickness direction so as to be aligned one-to-one with the plurality of terminals 107 in the third direction so that the plurality of terminals 107 of the plurality of battery cells 101 are exposed.

[0063] The plurality of vent holes 167 may be formed penetrating the central portion 162 in the thickness direction so as to be aligned one-to-one with the plurality of vents 106 in the third direction so as to expose the plurality of vents 106 of the plurality of battery cells 101 .

[0064] The battery module 100A may further include a front frame 120, a rear frame 125, a pair of side plates 130, a bottom plate 137, and a holder 140. The front frame 120 may be disposed in front of the multiple battery cells 101 so as to cover a front surface of the battery cell 101 located most forward among the multiple battery cells 101 arranged in the first direction.

[0065] The rear frame 125 may be disposed behind the multiple battery cells 101 so as to cover the rear surface of the battery cell 101 located most rearward among the multiple battery cells 101 arranged in the first direction.

[0066] The pair of side plates 130 can be disposed to cover both second surfaces 104 in the second direction of the multiple battery cells 101 and face both second surfaces 104. Front end portions 132 of the pair of side plates 130 can be joined to both side surfaces 122 in the second direction of the front frame 120 by a method such as welding or application of an adhesive.

[0067] The rear ends 133 of the pair of side plates 130 can be joined to both side surfaces 127 of the rear frame 125 in the second direction by a method such as welding or applying an adhesive.

[0068] The bottom plate 137 may cover and support third surfaces of the plurality of battery cells 101. Lower ends 134 of the pair of side plates 130 may be joined to both side ends of the bottom plate 137 in the second direction by a method such as welding or applying an adhesive.

[0069] The multiple battery cells 101 included in the battery module 100A may be housed in an internal space defined by the front frame 120, the rear frame 125, the bottom plate 137, and the pair of side plates 130.

[0070] The holder 140 may be positioned on the insulating sheet 160A to cover the central portion 162 of the insulating sheet 160A. When pressure is applied in a direction in which the central portion 162 is lifted due to an abnormality in the plurality of battery cells 101, the holder 140 may hold the central portion 162 so as not to lift up to the first side.

[0071] The holder 140 may include a holder frame 141 and a top plate 150. In the embodiment shown in the drawings, the first side is described as an upper side, but the present invention is not limited thereto and various modifications are possible.

[0072] The holder frame 141 may extend along a rectangular path like a window frame. The holder frame 141 may include a lower plate portion 142, an upper plate portion 143, and a connecting wall portion 145. The lower plate portion 142 and the upper plate portion 143 may extend in a first direction. The upper plate portion 143 may be disposed above the lower plate portion 142 so as to be spaced apart from the lower plate portion 142. The connecting wall portion 145 may connect inner ends of the lower plate portion 142 and the upper plate portion 143 and extend in the first direction.

[0073] The holder 140 may have a long groove 146 that is open on both sides in the second direction and extends in the first direction by the lower plate 142, the upper plate 143, and the connecting wall 145. The top plate 150 may cover the terminals 107 and the insulating sheet 160A so that they are not exposed. The outer periphery 151 of the top plate 150 may be joined to the upper plate 143 by a method such as applying an adhesive, so that the top plate 150 may be joined to the holder frame 141.

[0074] A front end of the holder frame 141 may include a front frame coupler 147, and a rear end of the holder frame 141 may include a rear frame coupler 148. The front frame coupler 147 may be coupled to the front frame 120, and the rear frame coupler 148 may be coupled to the rear frame 125. In this way, the front and rear ends of the holder 140 may be fixedly coupled to the front frame 120 and the rear frame 125.

[0075] Each of the pair of side plates 130 may include a bent upper end 135 that bends and extends toward the inside of the battery cell 101. The bent upper end 135 may be inserted into the long groove 146 of the holder frame 141 and closely contact the upper surface of the lower plate portion 142. Thus, both sides of the holder 140 in the second direction may be coupled to the pair of side plates 130 so as not to be separated therefrom.

[0076] Both end portions in the second direction of holder 140 may be in close contact with central portion 162. Specifically, the lower surface of lower plate portion 142 may be in close contact with both sides in the second direction of central portion 162 of insulating sheet 160A. Other portions of central portion 162 excluding both end portions in the second direction of central portion 162 may be separated from holder 140.

[0077] According to the battery module 100A described above, even if an abnormal phenomenon such as high temperature heat generation, gas generation, volume expansion, or spark generation occurs in some of the battery cells 101 among the multiple battery cells 101 included in the battery module 100A, the first surface 103 of the battery cell 101 is covered by the insulating sheet 160A, so that the abnormal phenomenon can be prevented from spreading to other surrounding battery cells 101.

[0078] The holder 140, including the holder frame 141 that is in close contact with both side ends of the central portion 162 in the second direction, holds the central portion 162 from lifting up, thereby slowing the spread and spread of fire or explosion in the battery module 100A and reducing damage to human life and property.

[0079] When an abnormal phenomenon occurs in some of the battery cells 101 among the plurality of battery cells 101 included in the battery module 100A, only a portion 163 of the central portion 162 covering the battery cell 101 in which the abnormal phenomenon occurred in the portion of the insulating sheet 160A is separated from the other portion of the insulating sheet 160A along the cutting line 170, and the portion of the insulating sheet 160A covering the other battery cells 101 in which the abnormal phenomenon did not occur can maintain a state of covering the battery cell 101. Thus, the spread of the abnormal phenomenon to the other surrounding battery cells 101 can be more effectively suppressed.

[0080] FIG. 8 is a perspective view of a battery module according to a second embodiment of the present invention, showing that the holder is disassembled upward so as to be separated from the front frame, the rear frame, and a pair of side plates. FIG. 9 is an exploded perspective view of a battery module according to the second embodiment of the present invention. FIG. 10 is a cross-sectional view of FIG. 8 cut along XX, showing that the holder is connected to the front frame, the rear frame, and a pair of side plates. FIG. 11 is an enlarged view of portion XI of FIG. 10. FIG. 12 is an enlarged view of portion XII of FIG. 10. FIG. 13 is a perspective view of the insulating sheet of FIG. 9, showing that a portion is separated and lifted up along the cut line.

[0081] 8 to 13, a battery module 100B according to the second embodiment of the present invention includes a plurality of battery cells 101 and an insulating sheet 160B. The plurality of battery cells 101 are the same as the battery cells 101 included in the battery module 100A according to the first embodiment of the present invention shown in Figs. 1 to 8, and are denoted by the same reference numerals as the battery cells 101 included in the first embodiment of the present invention. Therefore, a description of the overlapping configuration will be omitted.

[0082] The insulating sheet 160B is a plate-like member made of an insulating material. The insulating sheet 160B may include a center portion 162 and a pair of side walls 180.

[0083] The central portion 162 may be formed of an insulating material. The central portion 162 covers the first surfaces 103 of the plurality of battery cells 101 arranged in the first direction. The central portion 162 may have a plurality of cut lines 170 formed therein and extending in the second direction.

[0084] Each of the plurality of cut lines 170 may be positioned to overlap a boundary line 112 between a pair of adjacent battery cells 101 among the plurality of battery cells 101, specifically, a first surface boundary line 112. The number of cut lines 170 formed in the central portion 162 may be one less than the number of the plurality of battery cells 101 arranged in the first direction.

[0085] Each cut line 170 may include a plurality of through holes 172 that penetrate the central portion 162 in the thickness direction and are arranged to be spaced apart from each other along a straight line extending in a second direction perpendicular to the first direction and the third direction. The length of the through holes 172 in the second direction may be longer than the distance between adjacent pairs of the through holes 172.

[0086] The insulating sheet 160B may be formed with a plurality of terminal holes 165 and a plurality of vent holes 167. The plurality of terminal holes 165 may be formed penetrating the central portion 162 in a thickness direction so as to be aligned one-to-one with the plurality of terminals 107 in the third direction so that the plurality of terminals 107 of the plurality of battery cells 101 are exposed.

[0087] A plurality of vent holes 167 may be formed penetrating the central portion 162 in the thickness direction so as to be aligned one-to-one with the plurality of vents 106 in the third direction so that the plurality of vents 106 of the plurality of battery cells 101 are exposed.

[0088] The pair of sidewalls 180 may be connected to both side ends of the central portion 162 and extend downward so as to cover a pair of second surfaces 104 in the second direction of the plurality of battery cells 101 arranged in the first direction. The pair of sidewalls 180 may be formed of the same insulating material as the material of the central portion 162. The central portion 162 and the pair of sidewalls 180 may be integrally molded or processed.

[0089] A plurality of separation slits 183 may be formed in each of the pair of side wall portions 180, penetrating the side wall portion 180 in the thickness direction and extending in a third direction perpendicular to the first direction and the second direction.

[0090] The multiple separation slits 183 may be positioned to overlap with a boundary line 113 between a pair of adjacent battery cells 101 among the multiple battery cells 101, specifically, the second surface boundary line 113, in the second direction.

[0091] The cut line 170 and the separation slit 183 may be connected at both end portions in the second direction of the central portion 162. The separation slit 183 may be open to a lower end of the side wall portion 180. The number of separation slits 183 formed in each side wall portion 180 may be one less than the number of the plurality of battery cells 101 arranged in the first direction.

[0092] With this configuration, each side wall portion 180 may be separated into the same number of side wall pieces 181 as the number of the battery cells 101. The multiple side wall pieces 181 belonging to one side wall portion 180 may be arranged in a first direction.

[0093] The pair of side wall portions 180 may be fixed to the pair of second surfaces 104 in the second direction of the plurality of battery cells 101. Specifically, lower end portions 105 (see FIG. 9 ) of the pair of second surfaces 104 of the plurality of battery cells 101 and inner surfaces of the plurality of side wall pieces 181 may be joined by a method such as applying an adhesive.

[0094] The battery module 100B may further include a front frame 120, a rear frame 125, a pair of side plates 130, a bottom plate 137, and a holder 140. The front frame 120, the rear frame 125, the pair of side plates 130, the bottom plate 137, and the holder 140 are included in the battery module 100A according to the first embodiment of the present invention shown in Figures 1 to 8 and have the same configurations as those indicated by the same reference numerals. Therefore, a description of the overlapping configurations will be omitted.

[0095] However, the pair of side plates 130 may be arranged to face the pair of side wall portions 180 so as to cover the pair of side wall portions 180, without directly facing the pair of second surfaces 104 in the second direction of the multiple battery cells 101.

[0096] According to the battery module 100B of the second embodiment of the present invention, the diffusion of heat and sparks through a pair of second surfaces 104 of the plurality of battery cells 101 is suppressed by the side wall portion 180, so that the diffusion of abnormal phenomena is further suppressed than in the case of the battery module 100A of the first embodiment of the present invention, and the propagation and diffusion of fires and explosions can be further delayed.

[0097] When the side wall portions 180 of the insulating sheet 160B are fixed to the pair of second surfaces 104 of the plurality of battery cells 101, if an abnormal phenomenon occurs in some of the plurality of battery cells 101, the insulating sheet 160B is fixed to the battery cells 101 with a stronger force than the insulating sheet 160A included in the first embodiment of the present invention, and therefore the phenomenon of being lifted up from the battery cells 101 can be significantly suppressed. Therefore, the propagation and diffusion of a fire or explosion in the battery module 100B can be further delayed.

[0098] Nevertheless, if an abnormal phenomenon occurs in some of the battery cells 101 among the plurality of battery cells 101 included in the battery module 100B, only a portion 161 of the insulating sheet 160B covering the battery cell 101 in which the abnormal phenomenon occurred can be separated from the other portions of the insulating sheet 160B along the cutting line 170, and the portions of the insulating sheet 160B covering the other battery cells 101 in which no abnormal phenomenon is occurring can be maintained in a state of covering the battery cells 101.

[0099] The portion 161 of the insulating sheet 160B separated along the cut line 170 may include a portion 163 of the central portion 162 and a pair of side wall pieces 181 connected to both ends of the portion 163. This makes it possible to more effectively prevent the abnormal phenomenon from spreading to other surrounding battery cells 101.

[0100] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is understood that various modifications and variations can be made by those having ordinary skill in the art to which the present invention pertains within the technical spirit of the present invention and the equivalent scope of the following claims. [Explanation of symbols]

[0101] 100A Battery Module 100B Battery Module 101 Battery Cell 102 Cell Body 103 Page 1 104 2nd page 105 Lower end 106 Vent 107 Terminal 112 Boundary, first surface boundary 113 Boundary line, second boundary line 120 Front Frame 122 Both sides 125 rear frame 127 Both sides 130 Side Plate 132 Front end 133 Rear end 134 Lower end 135 Upper end 137 Bottom Plate 140 Holder 141 Holder Frame 142 Lower plate part 143 Upper plate 145 Connecting wall 146 Nagamizo 147 Front frame connector 148 Rear frame connector 150 Top Plate 151 Outer periphery 160A Insulation Sheet 160B Insulation sheet 161 part 162 Central part 163 part 165 Terminal hole 167 Vent hole 170 lines 172 Through hole 180 Side wall 181 Side wall piece 183 Separation Slit

Claims

1. A plurality of battery cells arranged in a first direction; and an insulating sheet formed of an insulating material, including a central portion covering first surfaces of the plurality of battery cells, the central portion having at least one cut line extending in a second direction.

2. 2. The battery module of claim 1, wherein the cut line comprises a plurality of through holes that penetrate the central portion in a thickness direction and are arranged spaced apart from each other along a straight line extending in the second direction.

3. The battery module according to claim 1 , wherein the cut line is positioned to overlap a boundary line between a pair of adjacent battery cells among the plurality of battery cells.

4. a terminal of the battery cell is formed on the first surface of the battery cell; The battery module according to claim 1 , wherein a terminal hole is formed through the central portion in a thickness direction to expose the terminal.

5. a vent through which gas generated inside the battery cell is released is formed on the first surface of the battery cell; The battery module according to claim 1 , wherein a vent hole is formed in the central portion, the vent hole penetrating the central portion in a thickness direction to expose the vent.

6. The battery module according to claim 1 , further comprising: a holder that covers the central portion to prevent the central portion from lifting up to the first side.

7. The battery module according to claim 6 , wherein both side ends of the holder in the second direction are in close contact with the central portion.

8. The insulating sheet is 2. The battery module according to claim 1, further comprising: a pair of side wall portions formed of an insulating material, connected to both end portions in the second direction of the central portion, and extending downward so as to cover a pair of second surfaces in the second direction of the plurality of battery cells.

9. The battery module according to claim 8 , wherein the pair of side wall portions are fixed to the pair of second surfaces of the battery cells.

10. The battery module according to claim 8 , wherein each of the pair of side walls is formed with at least one separation slit penetrating the side wall in a thickness direction and extending in a third direction.

11. The battery module according to claim 10 , wherein the separation slit is positioned to overlap a boundary line between a pair of adjacent battery cells among the plurality of battery cells.

12. The battery module according to claim 11 , wherein the cutting line and the separation slit are connected to each other at both side ends of the central portion.

13. The battery module according to claim 11, wherein the separation slit is open to a lower end of the side wall portion.

14. The battery module according to claim 11, wherein the separation slits extend from both side ends of the central portion to lower ends of the sidewall portions.

15. a pair of side plates arranged to cover the pair of side wall portions and to face the pair of side wall portions; and The battery module according to claim 8 , further comprising: a holder covering the central portion, the holder having both side ends in the second direction coupled to the pair of side plates.

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