Battery module and battery pack including same

Abstract

A battery module according to one embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, a module frame surrounding the battery cell stack, end plates covering front and rear surfaces of the battery cell stack that are open in the module frame, a heat transfer member formed between the battery cell stack and the end plate, and a movement detection unit that detects movement of the heat transfer member.

Description

[Technical field]

[0001] [Cross-reference to related applications] This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0132639 dated October 6, 2021, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a battery module and a battery pack including the same, and more particularly to a battery module and a battery pack capable of diagnosing abnormalities in battery cells. [Background technology]

[0003] As technological development and demand for mobile devices increases, the demand for secondary batteries as an energy source is rapidly increasing. In particular, secondary batteries are attracting much attention not only for mobile devices such as mobile phones, digital cameras, laptops, and wearable devices, but also as an energy source for power devices such as electric bicycles, electric cars, and hybrid electric cars.

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

[0005] Since it is preferable that medium- to large-sized battery modules are manufactured with small size and weight, prismatic batteries and pouch-shaped batteries that can be stacked with high integration and have a small weight relative to their capacity are mainly used as battery cells for medium- to large-sized battery modules. Such battery modules have a structure in which a number of cell assemblies, each including a plurality of unit battery cells, are connected in series to obtain high output. The battery cells include positive and negative electrode current collectors, separators, active materials, electrolytes, etc., and can be repeatedly charged and discharged through electrochemical reactions between the components.

[0006] Meanwhile, as the need for large capacity structures, including the use of batteries as energy storage sources, has increased recently, there has been an increasing demand for a number of battery modules in which a number of secondary batteries are connected in series and / or parallel, and for battery packs having a multi-module structure in which the battery modules are assembled.

[0007] In addition, when constructing a battery pack by connecting multiple battery cells in series / parallel, a common method is to first construct a battery module consisting of at least one battery cell, and then use this at least one battery module to add other components to construct the battery pack.

[0008] In general, when a secondary battery is heated above an appropriate temperature, its performance may be degraded, and in the worst case, it may explode or catch fire. In particular, in a battery module or battery pack having a large number of secondary batteries, i.e., battery cells, the heat generated from the large number of battery cells may be added together in a small space, causing the temperature to rise rapidly and severely. In other words, a battery module having a large number of stacked battery cells and a battery pack having such a battery module mounted thereon can obtain high output, but it is difficult to remove the heat generated from the battery cells during charging and discharging. If the heat of the battery cells is not sufficiently dissipated, the battery cells deteriorate faster, their lifespan is shortened, and the possibility of explosion or fire increases.

[0009] Furthermore, battery modules included in vehicle battery packs are frequently exposed to direct sunlight and may be placed in high temperature conditions, such as in summer or in desert regions.

[0010] Heat generated from the battery cells of a conventional battery module is only released in one direction through a thermally conductive resin layer formed at the bottom of the battery cell stack and the bottom of the module frame. However, with the recent continuous increase in the need for high capacity, high energy, and rapid charging, the amount of current flowing through the busbars is increasing, and the heat generated from the busbars, battery cells, and electrode leads is also increasing. This heat is difficult to effectively cool using only the conventional cooling structure. In addition, it is difficult to accurately detect the presence or absence of gas pockets in the battery cells, which are more likely to occur when the battery cells are charged and discharged during rapid charging.

[0011] Therefore, there is a need for a new structure that can solve the busbar heat generation problem that occurs due to the need for high capacity, high energy, and rapid charging, and that can grasp the occurrence of gas pockets that occur in rapid charging conditions and enable diagnosis of abnormalities in battery cells. Summary of the Invention [Problem to be solved by the invention]

[0012] An object of the present invention is to provide a battery module that can solve the heat generation problem in battery cells and bus bars and can diagnose abnormalities in battery cells, and a battery pack including the battery module.

[0013] However, the problems that the present invention is intended to solve are not limited to those mentioned above, and problems not mentioned will be clearly understood by those having ordinary skill in the art to which the present invention pertains from this specification and the attached drawings. [Means for solving the problem]

[0014] A battery module according to one embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, a module frame surrounding the battery cell stack, end plates covering front and rear surfaces of the battery cell stack that are open in the module frame, a heat transfer member formed between the battery cell stack and the end plate, and a movement detection unit that detects movement of the heat transfer member.

[0015] The heat transfer member is made of a material having flowability, and is movable when a gas pocket occurs within the battery module.

[0016] The heat transfer member may be in the form of a gel.

[0017] The movement detector of the battery module according to an embodiment of the present invention may include a pressure sensor, and the pressure sensor may be formed to be in contact with the heat transfer member.

[0018] The module frame may include a frame member covering a lower portion and both sides of the battery cell stack and an upper plate covering an upper portion of the battery cell stack, and the movement detector of the battery module according to another embodiment of the present invention may include a hole formed in the upper plate.

[0019] When a gas pocket occurs within the battery module, the heat transfer member flows out through the holes in the upper plate.

[0020] According to another embodiment of the present invention, the battery module further includes a protruding member formed to be in contact with the heat transfer member and adjacent to the hole, and when a gas pocket occurs within the battery module, the protruding member can move toward an outside of the upper plate.

[0021] The battery module according to still another embodiment of the present invention further includes a groove formed inside the upper plate, and the protruding member can be fitted into the groove to be coupled thereto.

[0022] The battery module may further include a bus bar frame formed between front and rear surfaces of the battery cell stack and the end plates, and the heat transfer member may be formed in a space between the battery cell stack and the bus bar frame and in a space between the bus bar frame and the end plates.

[0023] The heat transfer member may entirely fill the space between the battery cell stack and the bus bar frame and the space between the bus bar frame and the end plate.

[0024] The battery may further include an electrode lead protruding from the battery cell stack, the heat transfer member being in contact with the electrode lead.

[0025] The heat transfer member may be in contact with the bus bars and the bus bar frame, and may include a plurality of bus bars attached to the bus bar frame, the heat transfer member being in contact with the bus bars and the bus bar frame.

[0026] The heat transfer member may be in contact with a bottom of the module frame and a top of the module frame.

[0027] A battery pack according to another embodiment of the present invention may include the battery module. Effect of the Invention

[0028] The battery module according to an embodiment of the present invention includes a heat transfer member, which can solve the heat generation problem of the battery cells and bus bars in a high current and fast charging environment, and can improve the stability of the battery module by solving the heat generation problem.

[0029] In addition, the heat transfer member fills the space between the battery cell stack and the bus bar frame, and the space between the bus bar frame and the end plate, thereby achieving the effect of improving the insulation performance of the battery module.

[0030] In addition, by sensing the movement and change of the heat transfer member due to the occurrence of gas pockets in the battery module, it is possible to diagnose the occurrence of gas pockets in the battery cells and abnormalities in the battery cells.

[0031] The effects of the present invention are not limited to the effects described above, and effects not mentioned will be clearly understood by those having ordinary skill in the art to which the present invention pertains from this specification and the accompanying drawings. [Brief description of the drawings]

[0032] [Figure 1] FIG. 2 is an exploded perspective view of the battery module of the present invention. [Diagram 2] FIG. 2 is a perspective view showing a battery module assembled from the components shown in FIG. 1. [Diagram 3] 3 is an enlarged view showing a cut along the P1 plane in FIG. 2. FIG. [Figure 4] FIG. 3 is an enlarged view showing a cut along the P2 plane in FIG. 2. [Diagram 5] 2 is a diagram illustrating a movement detector of a battery module according to an embodiment of the present invention; [Figure 6] 13 is a diagram illustrating a movement detector of a battery module according to another embodiment of the present invention. [Figure 7] FIG. 7 is an enlarged view of part A in FIG. 6. [Figure 8] 13 is a diagram illustrating a motion detector of a battery module according to still another embodiment of the present invention. [Figure 9] FIG. 9 is an enlarged view of part B in FIG. 8. [Figure 10] 13 is a diagram illustrating a motion detector of a battery module according to still another embodiment of the present invention. [Figure 11] FIG. 2 is a perspective view showing a battery cell included in the battery module of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, in which: FIG. 1 is a block diagram of a semiconductor device according to an embodiment of the present invention;

[0034] In order to clearly explain the present invention, parts that are not necessary for the explanation will be omitted, and the same reference numerals will be used throughout the specification to refer to the same or similar components.

[0035] In addition, the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of explanation, and the present invention is not necessarily limited to those shown in the drawings. In the drawings, thicknesses are enlarged to clearly express various layers and regions. In the drawings, thicknesses of some layers and regions are exaggerated for convenience of explanation.

[0036] In addition, when a part such as a layer, film, region, or plate is said to be "on" or "above" another part, this includes not only the case where it is "directly on" another part, but also the case where there is another part in between. Conversely, when a part is said to be "directly on" another part, it means that there is no other part in between. In addition, being "on" or "above" a reference part means being located above or below the reference part, and does not necessarily mean being located "on" or "above" the direction against gravity.

[0037] Additionally, throughout the specification, when a part is said to "comprise" a certain element, this means that it may further include other elements, but not excluding other elements, unless specifically stated to the contrary.

[0038] Also, throughout the specification, the term "in a plane" means when the subject part is viewed from above, and the term "in cross section" means when the subject part is cut vertically and viewed from the side.

[0039] The terms first and second used in this application may be used to describe various components, but the components should not be limited by the terms. The terms are used only to distinguish one component from another.

[0040] The battery module of the present invention will be described below with reference to FIGS. 1 to 4 and 11. FIG.

[0041] Fig. 1 is an exploded perspective view of a battery module of the present invention. Fig. 2 is a perspective view showing a battery module assembled from the components of Fig. 1. Fig. 3 is an enlarged view showing a section taken along the P1 plane of Fig. 2. Fig. 4 is an enlarged view showing a section taken along the P2 plane of Fig. 2. Fig. 11 is a perspective view showing a battery cell included in the battery module of the present invention.

[0042] 1 and 2, a battery module 100 according to the present embodiment includes a battery cell stack 120 in which a plurality of battery cells 110 are stacked, and a module frame 200 surrounding the battery cell stack 120.

[0043] First, the battery cell 110 is preferably a pouch-type battery cell and may be formed in a rectangular sheet-type structure. For example, referring to Fig. 11, the battery cell 110 according to this embodiment has a structure in which two electrode leads 111 and 112 face each other and protrude from one end 114a and the other end 114b of a cell body 113, respectively. That is, the battery cell 110 includes electrode leads 111 and 112 protruding in directions opposite to each other. More specifically, the electrode leads 111 and 112 are connected to an electrode assembly (not shown) and protrude from the electrode assembly (not shown) to the outside of the battery cell 110.

[0044] Meanwhile, the battery cell 110 can be manufactured by bonding one end 114a and the other end 114b of the cell case 114 and one side 114c connecting them with each other in a state where an electrode assembly (not shown) is housed in the cell case 114. In other words, the battery cell 110 according to this embodiment has a total of three sealing parts 114sa, 114sb, and 114sc, and the sealing parts 114sa, 114sb, and 114sc are structured to be sealed by a method such as heat fusion, and the other side may be a connecting part 115. The cell case 114 may be made of a laminate sheet including a resin layer and a metal layer.

[0045] In addition, the connecting portion 115 extends long along one edge of the battery cell 110, and a butt ear 110p may be formed at an end of the connecting portion 115. In addition, as the cell case 114 is sealed with the protruding electrode leads 111, 112 sandwiched therebetween, a terrace portion 116 may be formed between the electrode leads 111, 112 and the cell body 113. That is, the battery cell 110 may include the terrace portion 116 formed by extending from the cell case 114 in the direction in which the electrode leads 111, 112 protrude.

[0046] A plurality of such battery cells 110 may be configured, and the plurality of battery cells 110 may be stacked so as to be electrically connected to each other to form a battery cell stack 120. In particular, as shown in Fig. 1, the plurality of battery cells 110 may be stacked along a direction parallel to the y-axis. Thus, the electrode leads 111 and 112 protrude in the x-axis direction and the -x-axis direction, respectively.

[0047] Meanwhile, when the battery cell 110 is repeatedly charged and discharged, heat is generated, and the heat is particularly generated in the areas adjacent to the electrode leads 111 and 112. That is, since more heat may be generated by charging and discharging closer to the electrode leads 111 and 112 than in the center of the cell body 113, a structure for cooling these areas is required.

[0048] Meanwhile, the module frame 200 includes a frame member 300 that has an open top, front, and rear surface and covers the bottom and both sides of the battery cell stack 120, and an upper plate 400 that covers the top of the battery cell stack 120. However, the module frame 200 is not limited thereto and may be replaced with a frame of other shape such as an L-shaped frame or a monoframe that surrounds the battery cell stack 120 except for the front and rear surfaces. The battery cell stack 120 accommodated inside the module frame 200 can be physically protected through the module frame 200. In this case, the frame member 300 includes a bottom portion 300a that supports the bottom of the battery cell stack 120, and side portions 300b that extend upward from both ends of the bottom portion 300a.

[0049] The upper plate 400 may cover the open upper side of the module frame 200. The end plate 150 may cover the front and rear sides of the battery cell stack 120 that are open in the module frame 200. The end plate 150 may be coupled to the front and rear corners of the upper plate 400 and the front and rear corners of the module frame 200 by welding.

[0050] A bus bar frame 130 may be formed between the end plates 150 and the front and rear surfaces of the battery cell stack 120. A plurality of bus bars 160 attached to the bus bar frame 130 may protrude from the battery cells 110 and contact the electrode leads 111 and 112 attached to the bus bar frame 130.

[0051] In addition, the battery module 100 according to this embodiment further includes a thermally conductive resin layer 310 located between the underside of the battery cell stack 120 and the bottom of the module frame 200, i.e., the bottom 300a of the frame member 300, and the thermally conductive resin layer 310 can transfer heat generated from the battery cells 110 to the bottom of the battery module 100 and play a role in fixing the battery cell stack 120.

[0052] In conventional battery modules, heat generated from the battery cells is released through a thermally conductive resin layer formed under the battery cells. However, the thermally conductive resin layer has a problem in that it cannot efficiently cool the heat generated from the electrode leads on the front and rear of the battery cells, the busbar frame, and the busbars attached to the busbar frame. In addition, in conventional battery modules, the space between the battery cell stack and the busbar frame and the space between the busbar frame and the end plate are formed as empty spaces, which causes a problem of deterioration of insulation performance due to the inflow of moisture and foreign matter. Therefore, in a situation where high heat is generated in the electrode leads and busbars of the battery cells for a short period of time due to a high current flow, such as in fast charging, there is a need for a structure that can effectively cool the heat.

[0053] In addition, the conventional battery module has a problem in that when a gas pocket occurs in which the inner area of ​​the sealing part, such as the cell body and terrace part of the battery cell, protrudes and swells due to gas generated through the decomposition or side reaction of the electrolyte in the battery cell, it is not possible to clearly detect the occurrence of the gas pocket. In particular, the gas pocket causes the electrode lead of the battery cell and the part adjacent to the sealing part to swell, which increases the risk of the battery cell being damaged. Therefore, when the gas pocket occurs, there is a need for a structure that can detect the occurrence of the gas pocket by containing a material that flows due to the occurrence of the gas pocket and detecting the flow and movement of the material. In addition, by detecting the gas pocket, it is possible to diagnose the occurrence of an abnormality in the battery cell.

[0054] Therefore, the battery module 100 according to this embodiment includes a heat transfer member 500 formed between the battery cell stack 120 and the end plate 150, and further includes a movement detector 400H, 700, 800 that detects the movement of the heat transfer member 500.

[0055] 3 and 4, the heat transfer member 500 may be formed in the space between the battery cell stack 120 and the bus bar frame 130 and in the space between the bus bar frame 130 and the end plate 150. In addition, an insulating cover may be further formed in the space between the bus bar frame 130 and the end plate 150, so that the space between the bus bar frame 130 and the insulating cover may be filled with the heat transfer member 500.

[0056] In particular, the heat transfer member 500 may entirely fill the above-mentioned spaces. That is, the heat transfer member 500 may entirely fill the space between the battery cell stack 120 and the bus bar frame 130 and the space between the bus bar frame 130 and the end plate 150. Thus, the entirely filled heat transfer member 500 improves insulation performance and minimizes the possibility of moisture and foreign matter penetrating, thereby improving the stability of the battery module. If moisture or foreign matter enters from the outside, the bus bar 160 may be short-circuited and the life of the battery module 100 may be reduced. Therefore, the heat transfer member 500 can ensure the performance and improve the stability of the battery module by preventing moisture and foreign matter from entering the battery module and coming into contact with the bus bar 160 and the electrode leads 111 and 112.

[0057] Therefore, as described above, the heat transfer member 500 according to the present embodiment can be in contact with the electrode leads 111, 112. The electrode leads 111, 112, which are the parts of the battery cell 110 where a large amount of heat is generated, are the parts of the battery cell 110 that require the most cooling. However, there is no configuration that directly contacts the electrode leads 111, 112 to form a cooling path, which has been a problem. Therefore, in the case of the battery module 100 according to the present embodiment, the electrode leads 111, 112 can be effectively cooled by the heat transfer member 500. In particular, the heat transfer member 500 can be in surface contact with the electrode leads 111, 112, and the contact area is wide, which allows for effective cooling even when a large amount of heat is generated by the contact.

[0058] The heat transfer member 500 may also be in contact with the bus bars 160 and the bus bar frame 130. Heat generated from the bus bars 160 is cooled through the heat transfer member 500 and can be rapidly transferred through other components with which the heat transfer member 500 is in contact. In addition, the heat transfer member 500 may be in contact with each of the bus bars 160 formed in the battery module 100, thereby preventing physical contact between the bus bars 160. Therefore, a short circuit that may occur due to contact between the bus bars 160 may be prevented.

[0059] Further, the heat transfer member 500 may be in contact with the bottom of the module frame 200 and the top of the module frame 200. That is, the heat transfer member 500 may be in contact with the bottom 300a and the top plate 400 of the frame member 300. Specifically, referring to FIG. 4, the heat transfer member 500 may be formed to be in contact with the bottom 300a and the thermally conductive resin layer 310 of the frame member 300. Also, the heat transfer member 500 may be formed to be in contact with the top plate 400. Thus, the heat transfer member 500 may form an additional heat transfer path by contacting the bottom 300a, the thermally conductive resin layer 310 and the top plate 400 of the frame member 300, and transfer and release heat to the outside of the module. At this time, the heat transfer member 500 may be in surface contact with the above-described configuration. Since the heat transfer member 500 is formed to fill the space, it may achieve improved cooling efficiency by being in surface contact with the above-described configuration.

[0060] As described above, the heat transfer member 500 according to the present embodiment may be characterized by being formed to be in contact with a number of components. In particular, the heat transfer member 500 is in direct contact with the bus bar 160 and the electrode leads 111, 112, which generate a large amount of heat, and can instantly transfer the heat generated from the bus bar 160 and the electrode leads 111, 112 through a number of components, thereby improving the temperature difference between components in the battery module, particularly between each part of the battery cells.

[0061] At this time, the heat transfer member 500 may be made of a material having fluidity. The heat transfer member 500 may include a heat transfer material that is poured in and hardens, or may be in the form of a gel that does not harden completely. That is, the heat transfer member 500 may be formed in a gel form. The heat transfer member 500 is formed in a gel form, so that it can ensure cooling performance, and at the same time, since it has fluidity, it can respond to changes in some components within the battery module. Therefore, the heat transfer member 500 can be moved in situations such as when a gas pocket 600 occurs within the battery module, so that it can ensure continuous cooling performance.

[0062] In addition, the heat transfer member 500 may be made of a material having thermal conductivity or an insulating material, and thus, by forming the heat transfer member 500, it is possible to achieve an effect of improving the cooling performance and insulating performance through heat transfer.

[0063] The movement detector of the present invention will be described in detail below with reference to FIGS.

[0064] Fig. 5 is a view showing a motion detector of a battery module according to one embodiment of the present invention. Fig. 6 is a view showing a motion detector of a battery module according to another embodiment of the present invention. Fig. 7 is an enlarged view of part A of Fig. 6. Fig. 8 is a view showing a motion detector of a battery module according to still another embodiment of the present invention. Fig. 9 is an enlarged view of part B of Fig. 8. Fig. 10 is a view showing a motion detector of a battery module according to still another embodiment of the present invention.

[0065] 5, the movement detector 400H, 700, 800 of the battery module according to an embodiment of the present invention includes a pressure sensor 700, and the pressure sensor 700 may be formed to contact the heat transfer member 500. The pressure sensor 700 may be formed at any position of the battery module within a range in which it contacts the heat transfer member 500. As an example, referring to FIG 5, the pressure sensor 700 may be formed on the bus bar frame 130 so that the heat transfer member 500 is compressed due to the movement of the heat transfer member 500, and a pressure change can be easily detected and stable installation of the pressure sensor 700 can be ensured.

[0066] When a gas pocket 600 occurs, the heat transfer member 500 in contact with the battery cell 110 through the electrode leads 111, 112, etc. moves, causing an increase in internal pressure. Specifically, the occurrence of the gas pocket 600 narrows the space in which the heat transfer member 500 exists, and the heat transfer member 500 in the portion in which the gas pocket 600 occurs moves, causing a pressure change. Therefore, the pressure sensor 700 can detect the occurrence of the gas pocket 600 in the battery cell 110 and the occurrence of an abnormality in the battery cell 110 due to gas generation, by detecting the pressure change.

[0067] 6 and 7, a motion detector 400H, 700, 800 of a battery module according to another embodiment of the present invention may include a hole 400H formed in an upper plate 400. When a gas pocket occurs, the heat transfer member 500 is discharged to the outside through the hole 400H of the upper plate 400. The hole 400H may be formed to penetrate the upper plate 400. Therefore, the heat transfer member 500 is pushed by the gas pocket 600 and is discharged to the outside along the hole 400H formed in the upper plate 400.

[0068] At this time, by measuring the height (H) and width (W) of the heat transfer member 500 that has been discharged to the outside through the hole 400H, it is possible to predict whether or not a gas pocket 600 has occurred and the extent of its occurrence. In addition, since the occurrence of the gas pocket 600 is related to the performance of the battery cell 110, it is possible to check the shortening of the life span of the battery cell 110 and diagnose the occurrence of an abnormality by checking for the presence or absence of gas in the battery cell 110 by checking for the presence or absence of the gas pocket 600.

[0069] 8 and 9, the movement detector 400H, 700, 800 of the battery module according to another embodiment of the present invention may further include a protruding member 800 formed adjacent to the hole 400H and in contact with the heat transfer member 500. In this case, the protruding member 800 may move toward the outside of the upper plate 400 when a gas pocket 600 is generated.

[0070] Specifically, the protruding member 800 may be formed in a shape including a horizontal plane formed parallel to the upper plate 400 and a vertical plane extending vertically from the horizontal plane. Also, the protruding member 800 may be formed between the upper part of the heat transfer member 500 and the inner surface of the upper plate 400. Therefore, the horizontal plane of the protruding member 800 may be fixed to the inner surface of the upper plate 400, and the vertical plane may pass through the hole 400H.

[0071] At this time, if a gas pocket 600 occurs, the protruding member 800 is pushed upward by the movement of the heat transfer member 500. As the protruding member 800 moves upward, the vertical surface formed to pass through the hole 400H moves toward the outside of the upper plate 400, making the vertical surface visible to the naked eye even from the outside. Therefore, by checking the degree to which the vertical surface protrudes outward, it is possible to predict whether or not a gas pocket 600 will occur and the extent to which it will occur.

[0072] Referring to FIG. 10, the battery module according to another embodiment of the present invention further includes a groove 400G formed inside an upper plate 400, and a protrusion member 800 can be fitted and coupled to the groove 400G.

[0073] Specifically, a groove 400G formed by being indented from the hole 400H may be formed in the space between the outer surface and the inner surface of the upper plate 400. The groove 400G may be formed on both sides of the hole 400H. At this time, the horizontal surface of the protruding member 800 may be fitted and coupled to the groove 400G. At this time, even if the protruding member 800 is fitted and coupled, an excess space may be formed between the groove 400G and the horizontal surface. Therefore, when a gas pocket 600 occurs, the protruding member 800 rises due to the heat transfer member 500 flowing in through the hole 400H, so that the vertical surface of the protruding member 800 protrudes outward through the hole 400H. Therefore, by checking the degree to which the vertical surface protrudes outward, it is possible to predict whether or not a gas pocket 600 occurs and the degree of occurrence.

[0074] As described above, the movement detectors 400H, 700, 800 that detect the movement of the heat transfer member 500 according to the embodiment of the present invention allow the movement of the heat transfer member 500 to be confirmed by a sensor or with the naked eye when a gas pocket 600 occurs. Therefore, by detecting the presence or absence and the extent of the gas pocket 600, it is possible to predict the occurrence of an abnormality in the battery cell 110 and appropriately respond to the shortening of the life span of the battery cell and the occurrence of the abnormality.

[0075] In particular, if the gas pocket 600 increases, the possibility of damage to the sealing parts 114sa, 114sb, and 114sc of the battery cell 110 increases. Also, if electrolyte leakage occurs due to damage to the sealing parts 114sa, 114sb, and 114sc, the possibility of fire increases. Therefore, by detecting the occurrence of the gas pocket 600 using the heat transfer member 500 and the movement detection units 400H, 700, and 800 that detect the movement of the heat transfer member 500 according to the embodiment of the present invention, the safety of the battery cell 110 and the battery module 100 can be ensured.

[0076] Hereinafter, a battery pack according to still another embodiment of the present invention will be described.

[0077] The battery pack according to the present embodiment includes the battery module described above. In addition, the battery pack of the present invention may be constructed by packing one or more battery modules according to the present embodiment together with a battery management system (BMS) for managing the temperature and voltage of the battery and a cooling device.

[0078] The battery pack can be applied to various devices, including vehicles such as electric bicycles, electric cars, and hybrid cars, but the present invention is not limited thereto and can be applied to various devices that can use a battery module, which also fall within the scope of the present invention.

[0079] Although the preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the above-mentioned specific embodiments, and various modifications may be made by a person having ordinary knowledge in the technical field to which the invention pertains without departing from the gist of the present invention as claimed in the claims, and such modifications should not be understood individually from the technical ideas and perspectives of the present invention. [Explanation of symbols]

[0080] 100: Battery module 110: Battery cell 120: Battery cell stack 130: Busbar frame 150: End plate 160: Busbar 200:Module frame 300: Frame member 400: Top plate 400H: Movement sensor (hole) 500: Heat transfer material 600: Gas pocket 700: Movement sensor (pressure sensor) 800: Movement sensor (protruding member)

Claims

1. a battery cell stack in which a plurality of battery cells are stacked; a module frame surrounding the battery cell stack; end plates that cover the front and rear faces of the battery cell stack that are open in the module frame; a heat transfer member formed between the battery cell stack and the end plate; and In a battery module including a movement detector that detects the movement of the heat transfer member, the movement detector includes a pressure sensor formed to contact the heat transfer member, When a gas pocket occurs in the battery module, the heat transfer member moves, causing the pressure sensor to detect a pressure change.

2. The heat transfer member is made of a material having fluidity, The battery module according to claim 1 , wherein the heat transfer member is movable when the gas pocket occurs.

3. The battery module of claim 2 , wherein the heat transfer member is in the form of a gel.

4. A battery cell stack in which a plurality of battery cells are stacked, a module frame surrounding the battery cell stack; end plates that cover the front and rear faces of the battery cell stack that are open in the module frame; a heat transfer member formed between the battery cell stack and the end plate; and In a battery module including a movement detector that detects the movement of the heat transfer member, the module frame includes a frame member that covers a lower portion and both side surfaces of the battery cell stack, and an upper plate that covers an upper portion of the battery cell stack, the motion detector includes a hole formed in the upper plate, When a gas pocket occurs in the battery module, the heat transfer member flows out through the hole in the upper plate.

5. A battery cell stack in which a plurality of battery cells are stacked. a module frame surrounding the battery cell stack; end plates that cover the front and rear faces of the battery cell stack that are open in the module frame; a heat transfer member formed between the battery cell stack and the end plate; and In a battery module including a movement detector that detects the movement of the heat transfer member, the module frame includes a frame member that covers a lower portion and both side surfaces of the battery cell stack, and an upper plate that covers an upper portion of the battery cell stack, the movement detector includes a hole formed in the upper plate and a protruding member formed adjacent to the hole and in contact with the heat transfer member, When a gas pocket occurs within the battery module, the protruding member moves toward an exterior of the upper plate.

6. The battery module further includes a groove formed in the upper plate, The battery module according to claim 5 , wherein the protruding members are fitted and coupled to the grooves.

7. the battery module further includes a bus bar frame formed between the front and rear surfaces of the battery cell stack and the end plates, The battery module according to claim 1 , wherein the heat transfer members are formed in a space between the battery cell stack and the bus bar frame and in a space between the bus bar frame and the end plate.

8. The battery module according to claim 7 , wherein the heat transfer member entirely fills a space between the battery cell stack and the bus bar frame and a space between the bus bar frame and the end plate.

9. The battery module further includes an electrode lead protruding from the battery cell stack, The battery module according to claim 7 , wherein the heat transfer member is in contact with the electrode lead.

10. the battery module includes a plurality of bus bars attached to the bus bar frame, The battery module according to claim 7 , wherein the heat transfer member contacts the bus bar and the bus bar frame.

11. The battery module according to claim 1 or 4, wherein the heat transfer member is in contact with a bottom portion of the module frame and an upper portion of the module frame.

12. A battery pack comprising the battery module according to claim 1 or 4.

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