Patent Publication Number: US-2021184303-A1

Title: Battery Module

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to Korean Patent Application No. 10-2019-0169027 filed Dec. 17, 2019, the disclosure of which is hereby incorporated by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present disclosure relates to a battery module. 
     2. Description of Related Art 
     Unlike primary batteries, secondary batteries may be charged and discharged. Thus, secondary batteries may be applied to various fields of application such as digital cameras, mobile phones, laptop computers, hybrid vehicles, and the like. Examples of secondary batteries may include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-hydrogen batteries, lithium secondary batteries, and the like. 
     Much research has been conducted into lithium secondary batteries, having high energy density and discharge voltages, among such secondary batteries. Recently, lithium secondary batteries have been manufactured as pouch-type battery cells having flexibility to be configured and used in the form of a module through the connection of a plurality of pieces. 
     When the battery module is used for an elongated period of time, heat may be generated by the battery module. In particular, an internal temperature of the battery module may be rapidly increased during a charging operation thereof. In this case, such an increase in temperature of the battery module may shorten a lifespan of the battery module and may decrease efficiency of the battery module. In the worst case, ignition or explosion may occur therein. 
     To address the above issues, a structure in which heat of a battery module is dissipated by forming a cooling flow path in a module housing has been applied. However, a battery module according to the related art cannot achieve sufficient cooling performance. 
     When a battery module is damaged by external mechanical factors such as crushing, crashes, vibrations, shocks, and the like, breakage of the battery module may occur or an accident such as a battery explosion may occur. However, a battery module according to the related art suffers from lack of rigidity to maintain a structure and has poor structural stability. 
     SUMMARY OF THE INVENTION 
     An aspect of the present disclosure is to provide a battery module having enhanced structural stability (rigidity). 
     An aspect of the present disclosure is to provide a battery module having improved cooling performance. 
     According to an aspect of the present disclosure, a battery module comprises a module housing including a first plate in which one side is open, a second plate coupled with the first plate to form an internal space, and a partition member disposed across the internal space to couple the first plate with the second plate t; and a battery cell stack disposed in the internal space, in which a plurality of battery cells are stacked. 
     The first plate may include a lower plate, supporting a lower portion of the battery cell stack, and side plates extending from both sides of the lower plate to support side surfaces of the battery cell stack. 
     The module housing may be further provided with a cover plate covering side surface of the internal space formed by the first plate and the second plate, and the partition member may be coupled to the cover plate. 
     The partition member may be formed to be integrated with the first plate or the second plate. 
     The partition member may be provided with a plurality of partition members disposed to be spaced apart from each other. 
     The battery module may further comprise a lower cooling member disposed on a lower surface of the first plate to cool the module housing. The first plate is provided with lower surface protrusion portions disposed on both ends thereof to protrude downwardly. A height which the lower surface protrusion portions protrude from the lower surface of the first plate is greater than or equal to a height which the lower cooling member protrudes from the lower surface of the first plate. 
     The battery module may further include an upper cooling member disposed on an upper surface of the second plate to cool the module housing. The second plate may be provided with upper surface protrusion portions disposed on both ends thereof to protrude upwardly. A height which the upper surface protrusion portion protrudes from an upper surface of the second plate, may be greater than or equal to a height which the upper cooling member protrudes from the upper surface of the second plate. 
     The battery module may comprise a bonding portion in which the side plates and the second plate are welded, and a side protrusion portion may be formed in a portion of a circumference of the bonding portion. 
     The side protrusion portion may be formed on each of the second plate and the side plates. In addition, the side protrusion portion may be formed to have a height greater than or equal to a height of the bonding portion. 
     The side plates may include a step portion in which a step is formed inwardly of a portion coupled to the second plate, and the step portion may be received in a step receiving portion formed to be recessed in a lower surface of the second plate. 
     A sealing member may be disposed between the step portion and the step receiving portion. 
     The battery module may further include a heat transfer member coupling the battery cell stack and the module housing to dissipate heat from the battery cell stack to the module housing. 
     The heat transfer member may be disposed between an upper surface of the battery cell stack and a lower surface of the second plate and between a lower surface of the battery cell stack and an upper surface of the lower plate. 
     The battery cell stack may be comprises a pouch type cell including an accommodation portion accommodating an electrode assembly, and a sealing portion sealing the accommodation portion. The heat transfer member may be disposed on a region in which the sealing portion is not disposed. 
     The sealing portion is formed to be folded and fixed with an adhesion member. The sealing portion may be disposed between the upper surface of the battery cell stack and the lower surface of the second plate and is not disposed between the lower surface of the battery cell stack and the upper surface of the lower plate. 
     The upper cooling member or the lower cooling member may comprise a contact portion in contact with the upper surface or the lower surface and a flow path portion spaced apart from the upper surface or the lower surface to form a cooling flow path through which a coolant flows. The battery module may comprise a buffer pad disposed between the battery cell stack and the partition member of the module housing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of the present disclosure will be more clearly understood from the following detailed description, taken in conjunction with the accompanying drawings. 
         FIG. 1  is a perspective view of a battery module according to an example embodiment of the present disclosure. 
         FIG. 2  is an exploded perspective view of the battery module illustrated in  FIG. 1 . 
         FIG. 3  is a perspective view illustrating an example of a battery cell. 
         FIG. 4  is a schematic cross-sectional view take along line I-I′ of  FIG. 1 . 
         FIG. 5  is a partially enlarged view of portion “A” illustrated in  FIG. 4 . 
         FIG. 6  is a partially enlarged view of portion “B” illustrated in  FIG. 4 . 
         FIG. 7  is a partially enlarged view of portion “C” illustrated in  FIG. 5 . 
         FIGS. 8 to 10  are schematic cross-sectional views illustrating various modified examples concerning a structure of a first plate, a second plate, and a partition member constituting a module housing, respectively. 
     
    
    
     DESCRIPTION OF THE INVENTION 
     The terms and words used in the present specification and claims should not be interpreted as being limited to typical meanings or dictionary definitions, but should be interpreted as having meanings and concepts relevant to the technical scope of the present disclosure based on the rule according to which an inventor can appropriately define the concept of the term to describe most appropriately the appropriate method he or she knows for carrying out the present disclosure. Therefore, the configurations described in the embodiments and drawings of the present disclosure are merely appropriate embodiments but do not represent all of the technical spirit of the present disclosure. Thus, the present disclosure should be construed as including all the changes, equivalents, and substitutions included in the spirit and scope of the present disclosure at the time of filing this application. 
     Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this case, it is to be noted that like reference numerals denote like elements in appreciating the drawings. Moreover, detailed descriptions related to well-known functions or configurations will be ruled out in order not to unnecessarily obscure the subject matter of the present disclosure. Based on the same reason, it is to be noted that some components shown in the drawings are exaggerated, omitted or schematically illustrated, and the size of each component does not exactly reflect its actual size. 
     Hereinafter, a battery module  100  according to an example embodiment will be described with reference to accompanying drawings. 
       FIG. 1  is a perspective view of a battery module  100  according to an example embodiment,  FIG. 2  is an exploded perspective view of the battery module  100  illustrated in  FIG. 1 ,  FIG. 3  is a perspective view illustrating an example of a battery cell  120 ,  FIG. 4  is a schematic cross-sectional view take along line I-I′ of  FIG. 1 ,  FIG. 5  is a partially enlarged view of portion “A” illustrated in  FIG. 4 ,  FIG. 6  is a partially enlarged view of portion “B” illustrated in  FIG. 4 ,  FIG. 7  is a partially enlarged view of portion “C” illustrated in  FIG. 5 , and  FIGS. 8 to 10  are schematic cross-sectional views illustrating various modified examples concerning a structure of a first plate  160 , a second plate  170 , and a partition member  155  constituting a module housing  150 , respectively. 
     Referring to  FIGS. 1 to 10 , the battery module  100  according to an example embodiment may be configured to include a battery cell stack  110 , a module housing  150 , and a cooling member  190 . The battery module  110  may further include heat transfer members TA 1  and TA 2 . 
     Battery Cell Stack  110   
     As illustrated in  FIG. 2 , the battery cell stack  110  is configured by stacking a plurality of battery cells  120  illustrated in  FIG. 3  as an example. In the present embodiment, the battery cells  120  are stacked in a left-right direction (or a horizontal direction). However, the battery cells  120  may be configured to be stacked in a vertical direction, as necessary. 
     Each of the battery cells  120  may be a pouch-type secondary battery, and may have a structure in which an electrode lead  125  protrudes outwardly thereof. 
     The battery cell  120  may be configured in such a manner that an electrode assembly, not illustrated, is accommodated in a pouch  121 . The electrode assembly, not illustrated, may include a plurality of electrode plates and a plurality of electrode tabs, and may be accommodated in a pouch  121 . The electrode plate may include a positive electrode plate and a negative electrode plate, and the electrode assembly may be formed by staking a positive electrode plate and a negative electrode plate with a separator interposed therebetween in such a manner that wide surfaces of the positive electrode plate and the negative electrode plate face each other. The positive electrode plate and the negative electrode plate may be formed by applying an active material slurry to a current collector. In general, the active material slurry may be prepared by stirring a granular active material, an auxiliary conductor, a binder, a plasticizer, and the like, in a state in which a solvent is added. In the electrode assembly, a plurality of positive electrode plates and a plurality of negative electrode plates are stacked in a left-right direction (or a horizontal direction). In this case, each of the positive electrode plates and the negative electrode plates may be provided with an electrode tab. The positive electrode plate and the negative electrode plate may be connected to the same electrode lead  125  by bringing the same polarities thereof into contact with each other. 
     In  FIG. 3 , the battery cell  120  is illustrated as two electrode leads  125  are disposed to face in directions opposite each other. However, the two electrode leads  125  may be disposed to face in the same direction while having different heights. 
     The pouch  121  may be formed in a container shape to provide an internal space in which an electrode assembly and an electrolyte, not illustrated, are accommodated. In this case, a portion of the electrode lead  125  of the electrode assembly may be exposed outwardly of the pouch  121 . 
     The pouch  121  may be divided into an accommodation portion  122  and a sealing portion  123 . The accommodation portion  122  may be formed in a container shape to provide a rectangular internal space. The electrode assembly and the electrolyte may be accommodated in the internal space of the accommodation portion  122 . 
     The sealing portion  123  may be a portion, to which a portion of the pouch  121  is bonded, to seal an external surface of the accommodation portion  122 . Accordingly, the sealing portion  123  may formed in the shape of a flange extending outwardly of the accommodation portion  122  formed in a container shape, and may be disposed along an external surface of the accommodation portion  122 . A thermal fusion process may be used to bond the pouch  121  for forming the sealing portion  123 , but the present disclosure is not limited thereto. 
     In the present embodiment, the sealing portion  123  is divided into a first sealing portion  123   a , in which an electrode lead  125  is disposed, and a second sealing portion  123   b  in which the electrode lead  125  is not disposed. 
     In the present embodiment, the pouch  121  may be manufactured by forming a piece of exterior material. More specifically, the manufacturing of the pouch  121  may be completed by forming one or two accommodating portions on apiece of exterior material and folding the exterior material such that the accommodating portions form one space (for example, the accommodating portion  122 ). 
     In the present embodiment, the accommodation portion  122  may be formed to have a rectangular shape. An external surface of the accommodation portion  122  may be provided with the sealing portion  202  formed by bonding the exterior material. However, as described above, it is unnecessary to form the sealing portion  202  on a surface on which the exterior material is folded. Therefore, in the present embodiment, the sealing portion  202  may be formed on the external surface of the accommodating portion  204 , and may be provided on only three sides of the accommodating portion  204  whereas the sealing portion  202  may be not disposed on any one side (a lower surface in  FIG. 3 ) of the external surfaces of the accommodating portion  204 . 
     In the present embodiment, since the electrode leads  125  are disposed to face in directions opposite each other, the two electrode leads  125  may be disposed in the sealing portions  123  formed on different sides. Accordingly, the sealing portion  123  may include two first sealing portion  123   a , in which the electrode lead  125  is disposed, and one second sealing portion  123   a  in which the electrode lead  125  is not disposed. In  FIG. 3 , the second sealing portion  123   b  is illustrated as being formed on an upper surface of the pouch  121 . However, the second sealing portion  123   b  may be formed on a lower surface of the pouch  121 . 
     A structure of the pouch  121 , applied to an example embodiment of the present disclosure, is not limited to a structure in which one piece of exterior material is folded to form the sealing portion  123  on three surfaces, as illustrated in  FIG. 3 . For example, the pouch  121  may have a structure in which an accommodation portion  122  is formed by overlapping two pieces of exterior material and sealing portions  123  are formed on all (four) sides of an external surface of the accommodation portion  122 . In this case, the sealing portion  123  may include two first sealing portions  123   a , in which the electrode lead  125  is disposed, and two second sealing portions  123   b  in which the electrode lead  125  is not disposed. The second sealing portions  123   b  may be formed on an upper surface and a lower surface of the battery cell  120 . 
     In addition, the battery cell  120  according to the present embodiment may be manufactured in such a manner that the sealing portion  123  is folded at least once to enhance adhesion reliability of the sealing portion  123  and to significantly decrease an area of the sealing portion  123 . 
     More specifically, in the sealing portion  123  according to the present embodiment, the second sealing portion  123   b , in which the electrode lead  125  is not disposed, may be folded twice and then fixed by an adhesion member  124 . For example, the second sealing portion  123   b  may be folded 180 degrees along a first folding line C 1  illustrated in  FIG. 3 , and may then be folded again along a second folding line C 2  illustrated in  FIG. 3 . In this case, the internal space of the second sealing portion  123   b  may be filled with the adhesion member  124 . Accordingly, the second sealing member  123   b  may be maintained in a twice-folded shape by the adhesion member  124 . The adhesive member  124  may be formed of an adhesive having high thermal conductivity. For example, the adhesive member  124  may be formed of epoxy or silicone, but the present disclosure is not limited thereto. 
     The above-configured battery cell  120  may be a nickel metal hydride (Ni-MH) battery or a lithium ion (Li-ion) battery, capable of charging and discharging electricity. 
     The battery cell  120  may be disposed in the internal space of the module housing  150  to be described later. A plurality of battery cells  120  may be horizontally stacked, while standing upright, to constitute the battery cell stack  110 . 
     As illustrated in  FIG. 4 , at least one buffer pad  127  may be disposed between the battery cells  120  disposed to be stacked. A single or a plurality of buffer pads  127  may be disposed between accommodation portions  120  of an adjacent battery cell  120 . Also, the buffer pad  127  may be disposed between the battery cell  120  and a side surface of the module housing  150 . The buffer pad  127  may be disposed between the battery cell stack  110  and a partition member  155  of the module housing  150 . Since the buffer pad  127  may be compressed and elastically deformed when a specific battery cell  120  swells, the buffer pad  127  may prevent an overall volume of the battery cell stack  110  from increasing. To this end, the buffer pad  127  may be formed of polyurethane foam, but the present disclosure is not limited thereto. 
     Module Housing  150   
     The module housing  150  may define an exterior of the battery module  100 , and may be disposed outside the battery cell stack  110  to protect the battery cell  120  from an external environment. In this case, the module housing  150  according to the present embodiment may also serve to cool the battery module  100 . 
     The module housing  150  may be configured to include a first plate  160  and a second plate  170 . The first plate may have a cross-sectional shape in which one side is open, for example, a U-shaped cross-sectional shape (in the present specification, a U-shaped cross section has an angular shape on an edge thereof). The second plate  170  may be combined with the first plate  160  to form an internal space. Also, the module housing  150  may include cover plates  180  disposed on a front surface and a rear surface of the module housing  150  to cover the internal space formed by the first plate  160  and the second plate  170 . 
     The battery cell stack  110  may be disposed in the internal space of the module housing, and at least one surface constituting the module housing  150  may serve as a heat dissipation plate to dissipate heat, generated within the battery cell  120 , outwardly of the module housing  150 . 
     In  FIGS. 1, 2, and 4 to 10 , the first plate  160  having a U-shaped cross section is illustrated as being disposed in a lower portion of the module housing  150 , and the second plate  170  is illustrated as being disposed to be coupled to the first plate  160  in an upper portion of the module housing  150 . However, the first plate  160  having a U-shaped cross section may be disposed in an upper portion of the module housing  150 , and the second plate  170  may be disposed to be coupled to the first plate  160  in an upper portion of the module housing  150 . For ease of description, a description will be given of a structure in which the first plate  160  is disposed in a lower portion of the module housing  150 , as illustrated in  FIGS. 1, 2, and 4 to 10 . 
     As illustrated in  FIGS. 2, 4 , and the like, the first plate  160  may include a lower plate  161 , supporting a lower portion of the battery cell stack  110 , and a sideplate  165 , supporting a side surface on which the accommodation portion  122  of the battery cell  120  is disposed, to form a U-shaped cross section in which one side is open. However, the side plate  165  and the lower plate  161  may be prepared as independent components and may then be coupled to/combined with each other, as necessary. 
     The side plate  165  may be formed to extend from both sides of the lower plate  161 , and may be disposed on a side surface of the battery cell stack  110 , disposed and stacked in the left-right direction, to support the accommodation portion  122  of the battery cell  120 . 
     The side plates  165  may be configured to be in direct contact with the accommodation portions  204  of the battery cells  120  to securely support the battery cell stack  110 . However, the present disclosure is not limited thereto, and various modifications may be made, as necessary. For example, a heat dissipation pad, the buffer pad  127 , or the like, may be interposed between the side plate  165  and the accommodation portions  122  of the battery cell. 
     The above-configured first plate  160  may be formed of a material having high thermal conductivity such as a metal. For example, the first plate  160  may be formed of an aluminum material. However, the material of the first plate  160  is not limited thereto, and may be any non-metallic material as long as it has strength and thermal conductivity similar to those of a metal. 
     The second plate  170  (or an upper plate) may be disposed above the battery cell stack  110  to correspond to an upper surface of the battery cell stack  110 . In addition, the second plate  170  may be coupled to an upper end of the side plate  165  of the first plate  160 . Accordingly, when the second plate  170  is coupled to the first plate  160 , the second plate  170  and the first plate  160  have a shape of a hollow tubular member. 
     Similarly to the first plate  160 , the second plate  170  may be formed of a material having high thermal conductivity such as a metal. As an example, the second plate  170  may be formed of an aluminum material. However, the material of the second plate  170  is not limited thereto, and may be any non-metallic material as long as it has strength and thermal conductivity similar to those of a metal. 
     The module housing  150  may include a partition member  155  disposed across an internal space, formed in the module housing  150 , to couple the first plate  160  and the second plate  170  to each other. As illustrated in  FIG. 2 , a plurality of battery cells  120  may be stacked between the partition member  155  and the side plate  165 . 
     The partition member  155  may be vertically disposed inside the module housing  150  to resist vertical external factors. Thus, the partition member  155  may increase overall rigidity of the module housing  150  to reduce damage to the battery module  100  caused by mechanical external factors such as crushing, crashes, vibrations, shocks, and the like. 
     As illustrated in  FIGS. 2, 4 and 8 , the partition member  155  may be formed to be integrated with the second plate  170  having a linear cross section, and may have a structure fixed to the lower plate  161  of the first plate  160  having a U-shaped cross section. For example, the second plate  170  and the partition member  155  may be integrally configured to have a T-shaped cross section. The partition member  155  and the first plate  160  may be coupled to each other using various known methods such as bolt (screw) fastening, welding, bonding, and the like. 
     As illustrated in  FIG. 9 , the partition member  155  may be formed to be integrated with the lower plate  161  of the first plate  160  and may have a structure fixed to the second plate  170  having a U-shaped cross section. For example, the first plate  160  and the partition member  155  may be integrally configured to have a laterally lying E-shaped cross section. The partition member  155  and the second plate  170  may be coupled to each other using various known methods such as bolt (screw) fastening, welding, bonding, and the like. 
     Alternatively, as illustrated in  FIG. 10 , the partition member  155  may be provided independently of the first plate  160  and the second plate  170  to be fixed to each of the first plate  160  and the second plate  170 . The partition member  155  may be coupled to the first plate  160  and the second plate  170  using various known methods such as bolt (screw) fastening, welding, bonding, and the like. 
     Similarly to the first plate  160  or the second plate  170 , the partition member  155  may be formed of a material having high thermal conductivity such as a metal. As an example, the partition member  155  may be formed of an aluminum material. However, the material of the partition member  155  is not limited thereto, and may be any non-metallic material as long as it has strength and thermal conductivity similar to those of a metal. 
     In addition, the partition member  155  may also be coupled to a front surface and a rear surface of the module housing  150  to increase the rigidity of the module housing  150 . For example, the partition member  155  may be fixed to a cover plate  180  covering the front surface and the rear surface of the module housing  150 . The partition member  155  may be fixed to the cover plate  180  using various known methods such as bolt (screw) fastening, welding, bonding, and the like. For example, the partition member  155  and the cover plate  180  may be coupled by a screw-coupling method. In this case, a fastening groove  155   a  for screw coupling may be formed in the partition member  155 , as illustrated in  FIG. 4 . 
     In  FIGS. 2, 4, and 8 to 10 , the module housing  150  is illustrated as being provided with only one partition member  155 . However, the module housing  150  may be provided with a plurality of partition members  155 . For example, a plurality of partition members  155  may be disposed to be spaced apart from each other, and a plurality of battery cells  120  may be stacked between the partition members  155  or between the partition member  155  and the side plate  165 . 
     The first plate  160  and the second plate  170  may be coupled to each other by welding a contact surface between the side plate  165  and the second plate  170  (for example, laser welding, or the like). 
     Referring to  FIG. 7 , the side plate  165  and the second plate  170  of the first plate  160  may be welding-coupled to each other in a bonding portion W formed to elongate along the contact surface between the side plate  165  and the second plate  170 . In this case, the bonding portion W may have a shape protruding outwardly of a side surface due to a welding bead formed by the welding coupling. Since the bonding portion W is vulnerable to external impact, it is necessary to prevent damage to the boding portion W. 
     According to an example embodiment, side protrusion portions A 1  and A 2 , protruding in a height direction of the boding portion W (the left-right direction in  FIG. 7 ), may be formed in at least a portion of an external surface of the bonding portion W to prevent damage to the bonding portion W and to protect the bonding portion W. Therefore, the contact surface between the side plate  165  and the second plate  170  may be disposed in a portion recessed to a lower level than the side protrusion portions A 1  and A 2 , for example, in a recessed portion A 3  between the side protrusion portions A 1  and A 2 . 
     In this case, the side protrusion portions A 1  and A 2  may be formed on a side surface of the second plate  170  and a side surface of the side plate  165 , respectively, to protect the bonding portion W on an upper side and a lower side of the bonding portion W. The side protrusion portions A 1  and A 2  may elongate along the contact surface between the sideplate  165  and the second plate  170 . However, the side protrusion portions A 1  and A 2  do not need to be continuously formed, and may be intermittently formed on the upper and lower sides of the bonding portion W in the case in which the bonding portion W may be protected. 
     A height H 3  of each of the side protrusion portions A 1  and A 2  may be greater than or equal to, in detail, greater than a height of the welding bead formed by the bonding portion W (for example, a height of protruding in a direction of the side surface) to prevent the bonding portion W from protruding outwardly of the side protrusion portions A 1  and A 2 . 
     Referring to  FIG. 7 , the side plate  165  may be provided with a step portion  166  in which a step is formed inwardly of an upper side portion coupled to the second plate  170 . The step portion  166  may be received in a step receiving portion  173  formed to be recessed in a lower surface  171  of the second plate  170 . 
     In addition, the second plate  170  may be provided with an extension portion  174  protruding outwardly of the step receiving portion  173  to correspond to a side surface of the step portion  166 . 
     As described above, the contact area between the side plate  165  and the second plate  170  may be increased through an insertion coupling structure, in which the step portion  166  is inserted in the step receiving portion  173 , and/or an overlap coupling structure of the step portion  166  and the extension portion  174 . Thus, rigidity of a bonded portion may be increased. 
     In addition, since a plurality of steps are formed through the step portion  166  and the step receiving portion  173 , it may be difficult for external moisture to permeate into the module housing  150 . In particular, when a sealing member OR is disposed between the step portion  166  and the step receiving portion  173 , external moisture may be securely prevented from permeating into the module housing  150 . The sealing member OR may be a known sealing material, for example, rubber such as ethylene-propylene-diene monomer (EPDM), silicone, a butyl-based material, or the like. 
     However, the coupling of the first plate  160  and the second plate  170  is not limited to the above-described welding coupling, and may be performed using various modified methods. For example, the coupling of the first plate  160  and the second plate  170  may be performed using a sliding manner, bonding, or a fixing member such as a bolt or a screw. 
     While repeatedly charging and discharging electricity, the battery module  100  may suffer from swelling in which the battery cell  120  expands in a direction of the side plate  165  of the module housing  150  to cause a portion of the side plate  165  to be convexly deformed. Due to the swelling, stress may be concentrated on a bonding portion W, relatively vulnerable to the stress, to damage the bonding portion W. 
     To prevent such damage to the bonding portion W and to sufficiently resist the swelling, a side protrusion portions A 2  may be formed on a portion of the side plate  165  disposed below the bonding portion W, and the side plate  165  disposed below the side protrusion A 2  may be formed to have a thickness t 1  less than a thickness t 2  of the side protrusion A 2 , as illustrated in  FIG. 7 . 
     Specifically, when swelling occurs, a central portion of the side plate  165  in a height direction  165  may be most swollen and deformation force may act on upper and lower sides of the side plate  165 , and stress may be concentrated on a relatively vulnerable portion. According to the present embodiment, since the thickness t 1  of the side plate  165  disposed below the side protrusion portion A 2  is less than the thickness t 2  of the side protrusion portion A 2 , a point in which swollen deformation starts, for example, a swelling point (SP in  FIG. 7 ) may be formed in a lower step portion of the side protrusion portion A 2 . For example, according to the present embodiment, since the deformation force caused by the swelling is not transferred to the bonding portion W but is concentrated on a lower step portion of the side protrusion portion A 2 , damage to or breakage of the bonding portion W, occurring when the stress is concentrated on the bonding portion W, may be prevented. Thus, structural stability (rigidity) of the module housing  150  and the battery module  100  may be significantly improved. 
     The cover plate  180  may be coupled to both side surfaces on which the electrode lead  125  of the battery cell  120  is disposed, for example, the front and rear surfaces of the module housing  150 , based on what is illustrated in  FIG. 1 . 
     As illustrated in  FIG. 2 , the cover plate  180  may be coupled to the first plate  160  and the second plate  170  to form an exterior of the module housing  150  together with the first plate  160  and the second plate  170 . 
     The cover plate  180  may be formed of a metal such as aluminum (A 1 ), and may be manufactured by a process such as die casting, extrusion/pressing, or the like. In addition, the cover plate  180  may have a through-hole  182  for exposing a connection terminal  132  of an insulating cover  130  to be described later to an external entity. 
     The cover plate  180  may be coupled to the first plate  160  and the second plate  170  through a fixing member such as a screw or a bolt. However, the coupling method of the cover plate  180  is not limited thereto. 
     Referring to  FIG. 2 , the insulating cover  130  may be interposed between the cover plate  180  and the battery cell stack  110 . 
     The insulating cover  130  may be coupled to one surface or both surfaces of the battery cell  120  on which the electrode lead  125  is disposed. The electrode leads  125  may penetrate through the insulation cover  130  to be connected to each other outside the insulation cover  130 . To this end, the insulating cover  130  may be provided with a plurality of through holes  133  into which the electrode leads  125  are inserted. 
     In addition, the insulating cover  130  may be provided with a connection terminal  132  for connection to an external entity. Therefore, the battery cell  120  is electrically connected to the external entity through the connection terminal  132 . To this end, the electrode lead  125  may be electrically connected to the connection terminal  132  through a circuit wiring, not illustrated, provided in the insulating cover  130 . Such a circuit wiring may perform electrical connection depending on serial/parallel connection of modules through a bus bar formed of a copper material. 
     The connection terminal  132  may be exposed to an external entity through the through-hole  182  formed in the cover plate  180 , as illustrated in  FIG. 1 . Accordingly, the through-hole  182  of the cover plate  180  may be formed to have a size corresponding to a size and a shape of the connection terminal  132 . 
     In addition, the insulating cover  130  may include a circuit board (for example, a printed circuit board (PCB)) and a plurality of electronic devices such as a sensor, mounted on the circuit board, and the like. Thus, the insulating cover  130  may serve to sense a voltage of the battery cell  120 . 
     Cooling Member  190   
     Referring to  FIG. 2  and  FIGS. 4 to 6 , the cooling member  190  may be attached to at least one of an external surface of the first plate  160  and an external surface of the second plate  170  to cool the plate  160  and/or the second plate  170 . For example, the cooling member  190  may dissipate heat, transferred to the first plate  160  through a lower surface of the battery cell stack  110 , and/or heat transferred to the second plate  170  through an upper surface of the battery cell stack  110 . Since the partition member  155  is coupled to the first plate  160  and/or the second plate  170 , the cooling member  190  may dissipate the heat transferred to the first plate  160  and/or the second plate  170  from the partition member  155 . As describe above, since the heat inside the module may also be dissipated through the partition member  155 , a heat transfer path may be expanded by mounting the partition member  155 . Thus, cooling performance of the module may be improved. 
     In order to effectively dissipate heat transferred from an upper portion and a lower portion of the battery cell stack  110  to improve cooling performance, the cooling members  190  may be attached to an eternal surface of the cooling member  190  and an external surface of the second plate  170  to cool the first plate  160  and the second plate  170 , respectively. 
     To this end, the cooling member  190  may include at least one of an upper cooling member  191 , disposed on an upper surface of the second plate  170 , and a lower cooling member  195  disposed on a lower surface of the lower plate  161 . 
     The upper cooling member  191  may be provided with a contact portion in contact with an upper surface of the second plate  170  and a flow path portion  191   b  spaced apart from the upper surface of the second plate  170  to form a cooling flow path  192  through which a coolant flows. 
     The lower cooling member  195  may be provided with a contact portion  195   a  in contact with a lower surface of the lower plate  161  and a flow path portion  195   b  spaced apart from the lower surface of the lower plate  161  to form a cooling flow path  196 . 
     In this case, coupling of the upper cooling member  191  and the second plate  170  and coupling of the lower cooling member  195  and the lower plate  161  may be performed using a known bonding method such as brazing, or the like. 
     The cooling member  190  may be a water-cooled cooling device in which a cooling liquid flows through the cooling paths  192  and  196 . However, the configuration of the cooling member  190  applied to the present disclosure is not limited thereto, and the cooling member  190  may be an air-cooled cooling device in which a gas such as air flows through the cooling paths  192  and  196 . 
     As described above, the cooling member  190  may be coupled to the second plate  170  and/or the lower plate  161  using brazing. 
     In the case of such bonding using brazing, the cooling member  190  may be heated to soften a material of the cooling member  190 , and thus, rigidity may be reduced. Therefore, the cooling member  190  may be vulnerable to external impact, or the like. 
     In view of the foregoing, according to an example embodiment, upper surface protrusion portion portions  172  may be formed on both ends of the second plate  170  to protrude upwardly of the upper cooling member  191  so as to protect the upper cooling member  191 . Referring to  FIG. 5 , a height H 1  at which the upper surface protrusion portion  172  formed on the second plate  170  protrudes from an upper surface of the second plate  170  may be greater than or equal to a height h 1  at which the upper cooling member  191  protrudes from the upper surface of the second plate  170 . 
     As described above, since the upper protrusion portion  172  may be formed on the second plate to have the height H 1  greater than or equal to, in detail, greater than the height h 1  of the upper cooling member  191 , the upper cooling member  191  may be protected from external impact applied from an upper side of the module housing  150 . 
     Similarly, a lower surface protrusion portion  162  may be formed on both ends of the lower plate  161  to protrude downwardly of the lower plate  161 . Referring to  FIG. 6 , a height H 2  at which the lower protrusion portion  162  formed on the lower plate  161  protrudes from a lower surface of the lower plate  161  may be greater than or equal to a height h 2  at which the lower cooling member  195  protrudes from the lower surface of the lower plate  161 . 
     As described above, since the height H 2  of the lower surface protrusion  162  formed on the lower plate  161  is greater than or equal to, in detail, greater than the height h 2  of the lower cooling member  195 , the lower cooling member  195  may be protected from external impact applied from the lower side of the module housing  150 . 
     Heat Transfer Members TA 1  and TA 2   
     The heat transfer members TA 1  and TA 2  may couple the battery cell stack  110  and the module housing  150  to each other to dissipate heat from the battery cell stack  110  to the module housing  150 . For example, one side of each of the heat transfer members TA 1  and TA 2  may be in contact with the battery cell stack  110  and the other side thereof may be in contact with the module housing  150  to transfer heat, generated within the battery cell  120 , to the module housing  150 . 
     For example, as illustrated in  FIGS. 4 to 6 , the heat transfer members TA 1  and TA 2  may be disposed between an upper surface of the battery cell stack  110  and a lower surface  171  of the second plate  170  and/or between a lower surface of the battery cell stack  110  and an upper surface of the plate  160 .  FIGS. 4 to 6  illustrate an example in which heat transfer members TA 1  and TA 2  are disposed on both an upper portion and a lower portion of the battery cell stack  110 . However, the configuration of the present disclosure is not limited thereto. As necessary, the heat transfer members TA 1  and TA 2  may be omitted or may be disposed in only one of the upper and lower portions of the battery cell stack  110 . 
     Referring to  FIGS. 4 and 5 , the heat transfer member TA 1  may be disposed between the upper surface of the battery cell stack  110  and the lower surface  171  of the second plate  170  to dissipate heat from the battery cell stack  110  to the second plate  170 . 
     Referring to  FIG. 3 , when the sealing portion  123  is formed on three sides by folding a piece of exterior material, the second sealing portion  123   b , on which the electrode lead  125  is not disposed, may be formed in only one of the upper and lower portions of the battery cell stack  110 . One the other hand, when the sealing portion  123  is formed on four sides by overlapping two pieces of exterior material, the second sealing portion  123   b , on which the electrode lead  125  is not disposed, may be formed on both the upper and lower portions of the battery cell stack  110 . 
     In this case, the heat transfer member TA 1  may be configured to couple the upper surface of the battery cell stack  110  and the lower surfaced  171  of the second plate  170  to each other in a region, in which the sealing portion  123  (the second sealing portion  123   b ) is not disposed, in the upper surface of the battery cell stack  110 . 
     Specifically, as illustrated in  FIG. 5 , the second sealing portion  123   b  of the battery cell  120  may have a structure folded and then bent to one of the left and right sides. As described above, since the second sealing portion  123   b  has a structure bonded (sealed) and then folded, an air space may be formed in a portion, in which folded surfaces overlap each other, and/or between a folded portion and the accommodation portion  122 . Accordingly, even when the heat transfer member TA 1  is disposed to cover the second sealing portion  123   b , heat transfer efficiency may be reduced due to the air space. Meanwhile, in the case of the region, in which the second sealing portion  123   b  is not disposed, in the upper surface of the battery cell stack  110 , the upper surface of the battery cell  120  may be in direct contact with the heat transfer member TA 1  to improve heat transfer efficiency between the battery cell stack  110  and the heat transfer member TA 1 . Therefore, when the heat transfer member TA 1  is disposed in a region in which the sealing portion  123  (the second sealing portion  123   b ) is not disposed, the amount of use of the heat transfer member TA 1  may be reduced while achieving sufficient heat transfer efficiency. However, in the present disclosure, a location of the heat transfer member TA 1  is not limited to the above-mentioned region in which the second sealing portion  123   b  is not disclose, and the heat transfer member TA 1  may be disposed on an entire upper surface of the memory cell  120  including the second sealing portion  123   b.    
     As illustrated in  FIG. 5 , the lower surface  171  of the second plate  170  may have a shape in which a portion, in which the heat transfer member TA 1  is disposed, protrudes downwardly of the second plate  170  in a V-shape. As described above, since the lower surface  171  of the second plate  170  has a protruding shape, the amount of use of the heat transfer member TA 1  may be reduced and a contact area with the heat transfer member TA 1  may be increased, as compared with a case in which the lower surface  171  of the second plate  170  has a flat structure. In addition, the second plate  170  may serve to guide and maintain a stacking location of the battery cell  120 . 
     In addition, referring to  FIGS. 4 and 6 , the heat transfer member TA 2  may be disposed between the lower surface of the battery cell stack  110  and the upper surface of the lower plate  161  to dissipate heat from the battery cell stack  110  to the lower plate  161 . In the case of the battery cell  120  illustrated in  FIGS. 4 and 6 , the second sealing portion  123   b  is not disposed on the lower surface of the battery cell  120 , so that the heat transfer member TA 2  may be disposed overall between the lower surface of the battery cell stack  110  and the upper surface of the lower plate  161 . 
     As described above, the second sealing portion  123   b , on which the electrode lead  125  is not disposed, may also be disposed in a lower portion of the battery cell  120 . When the second sealing portion  123   b  is disposed in a lower portion of the battery cell  120 , the heat transfer member TA 2  may be configured to couple the lower surface of the battery cell stack  110  and the lower plate  161  to each other in a region, in which the second sealing portion  123   b  is not located, so as to sufficiently achieve heat transfer efficiency and reduce the amount of use of the heat transfer member TA 1 . However, in the present disclosure, a location of the heat transfer member TA 2  is not limited to the region in which the second sealing portion  123   b  is not disposed, as described above. The heat transfer member TA 2  may be disposed on an entire lower surface of the battery cell  120  including the second sealing portion  123   b.    
     The configurations of the heat transfer members TA 1  and TA 2  may allow the heat, generated within the battery cell  120 , to be effectively transferred to the second plate  170  and/or the lower plate  161  due to high thermal conductivity of the heat transfer members TA 1  and TA 2 , and then may allow the heat to be sufficiently dissipated through the cooling member  190  (an upper cooling member  191 ) and/or the lower cooling member  195 . 
     The heat transfer members TA 1  and TA 2  may be configured to include at least some of a thermal grease, a thermal adhesive, thermally conductive epoxy, and a heat dissipation pad to facilitate heat transfer. However, the present disclosure is not limited thereto. 
     The heat transfer members TA 1  and TA 2  may be disposed between the upper surface of the battery cell stack  110  and the lower surface  171  of the second plate  170  and/or between the lower surface of the battery cell stack  110  and the upper surface of the first plate  160  in the form of pads, or may be applied in a liquid or gel state to be formed. 
     In addition, when the heat transfer members TA 1  and TA 2  are configured to couple the upper surface of the battery cell stack  110  and the lower surface  171  of the second plate  170  to each other and to couple the lower surface of the battery cell stack  110  and the upper surface of the first plate  160  to each other, both the upper surface and the lower surface of the battery cell stack  110  may be coupled to the module housing  150 . For example, due to adhesive performance of the heat transfer members TA 1  and TA 2 , the battery cell stack  110  may be integrated with the module housing  150  via the heat transfer members TA 1  and TA 2 . Thus, overall rigidity of the battery module  100  may be increased. 
     The heat transfer members TA 1  and TA 2  according to the present embodiment may be configured to have high insulation property and may include, for example, a material having dielectric strength ranging from 10 to 30 KV/mm. In the case in which such a material having high insulation property is used, insulation between the battery cell stack  110  and the module housing  150  may be maintained by the heat transfer members TA 1  and TA 2  disposed around the battery cell stack  110  even when partial insulation breakdown occurs in the battery cell  120 . 
     As described above, in a battery module according to an example embodiment, structural stability (rigidity) of a battery module may be improved through a partition member provided inside a module housing. 
     In addition, in a battery module according to an exemplary embodiment, damage to a cooling member attached to an upper portion and/or a lower portion of a module housing may be reduced. 
     In addition, in a battery module according to an example embodiment, damage caused by external impact, directly applied to a bonding portion of a module housing, may be significantly reduced. 
     In addition, in a battery module according to an example embodiment, a swelling compensation structure may be provided to prevent a bonding portion of a module housing from fracturing when stress is concentrated on the bonding portion. 
     In addition, in a battery module according to an example embodiment, a battery cell may be integrated with a module housing to be fixed thereto. Thus, structural rigidity may be enhanced and heat dissipation performance may be improved. 
     In addition, in a battery module according to an example embodiment, cooling performance of a battery cell may be improved. Thus, overall cooling performance of the battery module may be improved. 
     In addition, in a battery module according to an example embodiment, heat generated within a battery cell may be dissipated through a cooling member via a first plate and a second plate, respectively disposed in an upper portion and a lower portion of the battery cell. Thus, cooling efficiency may be increased. In an example embodiment in which a partition member is provided, heat inside the module may be dissipated through the partition member to expand a heat transfer path and to further improve cooling performance. 
     In addition, in a battery module according to an example embodiment, the amount of use of a thermally conductive member, applied to an upper portion and/or a lower portion of a battery cell, may be reduced. 
     While exemplary embodiments have been shown and described above, it will be apparent to those skilled in the art that modifications and variations could be made without departing from the scope of the present disclosure as defined by the appended claims.