Patent Publication Number: US-2023148286-A1

Title: Battery module and battery pack including the same

Description:
CROSS CITATION WITH RELATED APPLICATION(S) 
     This application claims the benefit of Korean Patent Application No. 10-2020-0102355 filed on Aug. 14, 2020 with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The present disclosure relates to a battery module and a battery pack including the same, and more particularly, to a battery module that can adjust the amount of thermal conductive resin used, and a battery pack including the same. 
     BACKGROUND 
     In modern society, as portable devices such as a mobile phone, a notebook computer, a camcorder and a digital camera has been daily used, the development of technologies in the fields related to mobile devices as described above has been activated. In addition, chargeable/dischargeable secondary batteries are used as a power source for an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (P-HEV) and the like, in an attempt to solve air pollution and the like caused by existing gasoline vehicles using fossil fuel. Therefore, there is a growing need for development of the secondary battery. Currently commercialized secondary batteries include a nickel cadmium battery, a nickel hydrogen battery, a nickel zinc battery, a lithium secondary battery, and the like. Among them, the lithium secondary battery has come into the spotlight because they have advantages over nickel-based secondary batteries, for example, hardly exhibiting memory effects and thus being freely charged and discharged, and having very low self-discharge rate and high energy density. 
     Such lithium secondary battery mainly uses a lithium-based oxide and a carbonaceous material as a positive electrode active material and a negative electrode active material, respectively. The lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate each coated with the positive electrode active material and the negative electrode active material are disposed with a separator being interposed between them, and a battery case that seals and houses the electrode assembly together with an electrolyte solution. 
     Generally, the lithium secondary battery may be classified based on the shape of the exterior material into a can type secondary battery in which the electrode assembly is mounted in a metal can, and a pouch-type secondary battery in which the electrode assembly is mounted in a pouch of an aluminum laminate sheet. 
     In the case of a secondary battery used for small-sized devices, two to three battery cells are disposed, but in the case of a secondary battery used for a middle or large-sized device such as an automobile, a battery module in which a large number of battery cells are electrically connected is used. In such a battery module, a large number of battery cells are connected to each other in series or in parallel to form a battery cell stack, thereby improving capacity and output. In addition, one or more battery modules may be mounted together with various control and protection systems such as BMS (battery management system) and a cooling system to form a battery pack. 
       FIG.  1    is a perspective view of a conventional battery module, and  FIG.  2    is an exploded perspective view of the battery module of  FIG.  1   . 
     Referring to  FIGS.  1  and  2   , a conventional battery module  10  includes a battery cell stack  20  formed by stacking battery cells, a mono frame  30  for housing the battery cell stack  20 , and a thermal conductive resin layer  50  located between the battery cell stack  20  and the lower surface of the mono frame  30 . The mono frame  30  may be a metal plate material of which a front surface and a rear surface are opened, and the end plate  70  may cover the opened front and rear surfaces of the mono frame  30 . 
     Meanwhile, the conventional battery module  10  may further include an upper cover  41  housed in the mono frame  30  together with the battery cell stack  20 , and a busbar frame  42 . The upper cover  41  is located on the upper part of the battery cell stack  20  to prevent damage to the battery cell stack  20  when the battery cell stack  20  is inserted into the mono frame  30 . The busbar frame  42  may be located on the front surface and rear surface of the battery cell stack  20 , respectively. A busbar  43  connected to electrode leads of battery cells constituting the battery cell stack  20  may be mounted on the busbar frame  42 . 
     Meanwhile, a thermal conductive resin can be injected between the battery cell stack  20  and the lower surface of the mono frame  30  to form a thermal conductive resin layer  50 , and such a thermal conductive resin layer  50  may transfer heat generated from the battery cell stack  20  to the bottom of the battery module  10 . At this time, the method of forming the thermal conductive resin layer  50  in the conventional battery module  10  will be described with reference to  FIG.  3   . 
       FIG.  3    is a perspective view showing a state in which the lower surface of the battery module of  FIG.  1    is inverted so as to face upward. 
     Referring to  FIGS.  1  to  3   , an injection hole  30 H for injecting the thermal conductive resin may be formed on the lower surface of the conventional battery module  10 , that is, the lower surface of the mono frame  30 . 
     Specifically, the battery cell stack  20 , the upper cover  41 , the busbar frame  42  and the like are housed in the mono frame  30 , and then an end plate  70  covers the opened front and rear surfaces of the mono frame  30 . At this time, the mono frame  30  and the end plate  70  may be joined to each other by a method such as welding. After that, the thermal conductive resin may be injected via an injection hole  30 H to form a thermal conductive resin layer  50  between the battery cell stack  20  and the lower surface of the mono frame  30 . 
     However, since the injection is performed after the battery cell stack  20  is first housed, variations of the injection amount of the thermal conductive resin are large. Further, in the process of injecting the thermal conductive resin, it is possible to inject more than a predetermined fixed amount due to clearance or the like of the parts in the battery module, whereby the production cost of the battery module may increase, which may adversely affect profitability. 
     Further, in the injection process, the battery cell stack  20  may be pushed toward the upper surface of the mono frame  30  by the pressure of the thermal conductive resin, which may affect the dimensions of major parts such as a terminal busbar or the like. 
     Further, since the injection is performed via the injection hole  30 H, it is difficult for the thermal conductive resin layer  50  to form a constant thickness between the battery cell stack  20  and the lower surface of the mono frame  30 . This can be a cause of a variation in heat transfer performance by each zone. 
     Therefore, there is a need to develop a technology for a battery module capable of appropriately adjusting the amount of thermal conductive resin used. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Technical Problem 
     It is an object of the present disclosure to provide a battery module with a new structure capable of injecting an appropriate amount of a thermal conductive resin, and a battery pack including the same. 
     However, the problem to be solved by embodiments of the present disclosure is not limited to the above-described problems, and can be variously expanded within the scope of the technical idea included in the present disclosure. 
     Technical Solution 
     According to one embodiment of the present disclosure, there is provided a battery module comprising: a battery cell stack in which a plurality of battery cells are stacked; a plate-shaped lower plate located under the battery cell stack; a module frame for covering an upper surface and opposite side surfaces of the battery cell stack; and a thermal conductive resin layer located between the lower plate and the battery cell stack. 
     The module frame may include a first side surface and a second side surface for covering the opposite side surfaces of the battery cell stack; and a ceiling for covering the upper surface of the battery cell stack. 
     The first side surface, the second side surface and the ceiling may be integrally formed. 
     A first edge and a second edge of the lower plate opposite each other may be joined to the first side surface and the second side surface, respectively. 
     The first edge and the second edge may be weld-joined to the first side surface and the second side surface, respectively. 
     The lower plate may include a mounting part, and the mounting part may be formed on a first edge and a second edge of the lower plate facing each other. 
     A mounting hole may be formed in the mounting part, and the mounting part may extend parallel to one surface of the lower plate. 
     The thermal conductive resin layer may be formed by applying a thermal conductive resin to the lower plate. 
     The battery module may further include a compression pad that surrounds the thermal conductive resin layer. 
     Each of the plurality of battery cells may include electrode leads protruding in a first direction and a protrusion part formed on one edge of the battery cell. The protrusion part may be located closer to a first end of the lower plate in the first direction than the compression pad so that the protrusion part is between the first end and the compression pad. 
     The lower plate may include a stepped part formed at the first end of the lower plate, and the protrusion part may be located above the stepped part. 
     A thickness of the thermal conductive resin layer may be equal to or less than a thickness of the compression pad. 
     The thermal conductive resin layer may include a first thermal conductive resin layer and a second thermal conductive resin layer that are located apart from each other. 
     The battery module may further include a first compression pad surrounding the first thermal conductive resin layer and a second compression pad surrounding the second thermal conductive resin layer. 
     The lower plate may have a first side edge, a second side edge, a first end edge and a second end edge, and the lower plate may be planar. 
     The plurality of battery cells may be stacked in a first direction, and the first thermal conductive resin layer and a second thermal conductive resin layer may be located apart from each other in a second direction. 
     Advantageous Effects 
     According to embodiments of the present disclosure, the application of the thermal conductive resin in an appropriate amount can be realized through the structure of the plate-shaped lower plate and the module frame. 
     Also, the dimensional stability in the height direction of the battery module can be easily secured by adjusting the application amount of the thermal conductive resin and controlling the thickness of the compression pad section. 
     Further, the mounting structure is applied to the plate-shaped lower plate, thereby capable of realizing free design and simplification of a shape. 
     The effects of the present disclosure are not limited to the effects mentioned above and additional other effects not described above will be clearly understood from the description of the appended claims by those skilled in the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of a conventional battery module; 
         FIG.  2    is an exploded perspective view of the battery module of  FIG.  1   ; 
         FIG.  3    is a perspective view showing a state in which the lower surface of the battery module of  FIG.  1    is inverted so as to face upward; 
         FIG.  4    is a perspective view of a battery module according to an embodiment of the present disclosure; 
         FIG.  5    is an exploded perspective view of the battery module of  FIG.  4    in which the end plate is removed; 
         FIG.  6    is an exploded perspective view showing a battery cell stack, a busbar frame, and a busbar included in the battery module of  FIG.  5   ; 
         FIG.  7    is a perspective view of a battery cell included in the battery cell stack of  FIG.  6   ; 
         FIG.  8    is a perspective view of a module frame according to a comparative example of the present disclosure; 
         FIG.  9    is a perspective view of a lower plate according to an embodiment of the present disclosure; 
         FIG.  10    is a front view of the battery module of  FIG.  4    as viewed along the −x axis on the yz plane; 
         FIG.  11    is a perspective view showing a battery cell stack and a lower plate according to an embodiment of the present disclosure; 
         FIG.  12   a    is a cross-sectional view taken along the cutting line A-A′ of  FIG.  11   ; 
         FIG.  12   b    is a cross-sectional view taken along the cutting line B-B′ of  FIG.  11   ; 
         FIG.  13    is a perspective view showing a lower plate according to a modified embodiment of the present disclosure; 
         FIG.  14   a    is a cross-sectional view taken along the cutting line C-C′ of  FIG.  13   ; and 
         FIG.  14   b    is a cross-sectional view taken along the cutting line D-D′ of  FIG.  13   . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out them. The present disclosure may be modified in various different ways, and is not limited to the embodiments set forth herein. 
     A description of parts not related to the description will be omitted herein for clarity, and like reference numerals designate like elements throughout the description. 
     Further, in the drawings, the size and thickness of each element are arbitrarily illustrated for convenience of description, and the present disclosure is not necessarily limited to those illustrated in the drawings. In the drawings, the thickness of layers, regions, etc. are exaggerated for clarity. In the drawings, for convenience of description, the thicknesses of some layers and regions are exaggerated. 
     In addition, it will be understood that when an element such as a layer, film, region, or plate is referred to as being “on” or “above” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, it means that other intervening elements are not present. Further, the word “on” or “above” means disposed on or below a reference portion, and does not necessarily mean being disposed on the upper end of the reference portion toward the opposite direction of gravity. 
     Further, throughout the description, when a portion is referred to as “including” a certain component, it means that the portion can further include other components, without excluding the other components, unless otherwise stated. 
     Further, throughout the description, when referred to as “planar”, it means when a target portion is viewed from the upper side, and when referred to as “cross-sectional”, it means when a target portion is viewed from the side of a cross section cut vertically. 
       FIG.  4    is a perspective view of a battery module according to an embodiment of the present disclosure.  FIG.  5    is an exploded perspective view of the battery module of  FIG.  4    in which the end plate is removed.  FIG.  6    is an exploded perspective view showing a battery cell stack, a busbar frame, and a busbar included in the battery module of  FIG.  5   .  FIG.  7    is a perspective view of a battery cell included in the battery cell stack of  FIG.  6   . 
     Referring to  FIGS.  4  to  6   , a battery module  100  according to an embodiment of the present disclosure includes a battery cell stack  200  in which a plurality of battery cells  110  are stacked, a plate-shaped lower plate  300  located under the battery cell stack  200 , a module frame  400  for covering an upper surface and both side surfaces of the battery cell stack  200 , and a thermal conductive resin layer  500  located between the lower plate  300  and the battery cell stack  200 . Further, the battery module  100  may further include an end plate  700  located on the front surface and rear surface of the battery cell stack  200 , respectively, and an insulating cover having electrical insulation (not shown) may be located between the battery cell stack  200  and the end plate  700 . 
     First, the battery cell  110  is preferably a pouch-type battery cell, and may be formed in a rectangular sheet-like structure. For example, the battery cell  110  according to the present embodiment has a structure in which the two electrode leads  111  and  112  face each other and protrude from one end part and the other end part, respectively. 
     In particular, referring to  FIG.  7   , the battery cell  110  according to the present embodiment has a structure in which two electrode leads  111  and  112  face each other and protrude from one end part  114   a  and the other end part  114   b  of the cell body  113 , respectively. More specifically, the electrode leads  111  and  112  are connected to the electrode assembly (not shown), and protrude from the electrode assembly (not shown) to the outside of the battery cell  110 . 
     Meanwhile, the battery cell  110  can be manufactured by joining both end parts  114   a  and  114   b  of a cell case  114  and one side part  114   c  connecting them in a state in which an electrode assembly (not shown) is housed in a cell case  114 . In other words, the battery cells  110  according to the present embodiment have a total of three sealing parts ( 114   sa ,  114   sb ,  114   sc ), the sealing parts ( 114   sa ,  114   sb ,  114   sc ) have a structure in which it is sealed by a method such as heat fusion, and the remaining other one side part can be composed of a connection part  115 . The cell case  114  can be composed of a laminate sheet including a resin layer and a metal layer. 
     Further, the connection part  115  may extend long along one edge of the battery cell  110 , and a protrusion part  110   p  of the battery cell  110  called a bat-ear may be formed at an end part of the connection part  115 . However, the protrusion part  110   p  is an exemplary structure, and the battery cell  110  according to another embodiment of the present disclosure may have a form in which a protrusion part is not formed and the connection part  115  extends in a straight line. 
     The battery cell  110  may be configured by a plurality of numbers, and the plurality of battery cells  110  may be stacked so as to be electrically connected to each other, thereby forming a battery cell stack  200 . Particularly, as shown in  FIG.  6   , the plurality of battery cells  110  can be stacked along the y-axis direction. Thereby, one electrode lead  111  of the battery cells  110  may be protruded toward the x-axis direction, and the other electrode lead  112  may be protruded toward the −x-axis direction. 
     The lower plate  300  is a plate-shaped member, and the battery cell stack  200  may be seated thereon. The module frame  400  may include a first side surface part  410  and a second side surface part  420  that cover both side surfaces (y-axis direction and −y-axis direction) of the battery cell stack  200 , and a ceiling part  430  that covers the upper surface (z-axis direction) of the battery cell stack  200 . Specifically, the first side surface part  410  and the second side surface part  420  may be extended downward from both end parts of the ceiling part  430 . Further, the first side surface part  410 , the second side surface part  420 , and the ceiling part  430  may be integrally formed. The module frame  400  may form an n-shaped cross-section cut along the yz plane. 
     The lower plate  300  and the module frame  400  can be joined by welding or the like in a state in which the corresponding corner portions are in contact with each other, thereby forming a structure that covers the battery cell stack  200  vertically and horizontally. Specifically, the first edge part  310  and the second edge part  320  of the lower plate  300  facing each other may be abutted and joined on the first side surface part  410  and the second side surface part  420 , respectively. The joining method is not particularly limited, but it is preferable that the first edge part  310  and the second edge part  320  are weld-joined to the first side surface part  410  and the second side surface part  420 , respectively. 
     The battery cell stack  200  can be physically protected through the lower plate  300  and the module frame  400 . For this purpose, the lower plate  300  and the module frame  400  may include a metal material having a predetermined strength. 
     When the battery cell stack  200  is housed in the lower plate  300  and the module frame  400 , end plates  700  may be located on the opened front surface (x-axis direction) and rear surface (−x-axis direction) of the battery cell stack  200 . That is, the end plate  700  may be formed such that is located on the front surface (x-axis direction) and rear surface (−x-axis direction) of the battery cell stack  200  and covers the battery cell stack  200 . The end plate  700  may be joined to the lower plate  300  and the module frame  400  by a method such as welding. 
     The thermal conductive resin layer  500  may be formed by applying a thermal conductive resin to the lower plate  300 . Specifically, the thermal conductive resin may be applied onto the lower plate  300 , the battery cell stack  200  may be located thereon, and then the thermal conductive resin may be cured to form the thermal conductive resin layer  500 . 
     The thermal conductive resin may include a thermal conductive adhesive material, and specifically, may include at least one of silicone material, urethane material, and acrylic material. The thermal conductive resin is a liquid during application but is cured after application, so that it can perform the role of fixing a plurality of battery cells  110  constituting the battery cell stack  200 . Further, since the thermal conductive resin has excellent heat transfer properties, heat generated from the battery module  110  can be quickly transferred to the lower side of the battery module  100 , thereby preventing overheating of the battery module  100 . Heat generated from the battery cell  110  may be transferred to the outside of the battery module  100  via the thermal conductive resin layer  500 , the lower plate  300 , and a heat sink (not shown). 
     Meanwhile, the thermal conductive resin layer  500  may include a first thermal conductive resin layer  510  and a second thermal conductive resin layer  520  that are located apart from each other. Specifically, the first thermal conductive resin layer  510  and the second thermal conductive resin layer  520  may be disposed apart from each other along the direction in which the electrode leads  111  and  112  protrude from the battery cell  110 . Here, the direction in which the electrode leads  111  and  112  protrude from the battery cell  110  may correspond to the x-axis direction or the −x-axis direction. 
     When charge and discharge of the battery cell are repeatedly performed, a lot of heat is generated in portions adjacent to the electrode leads  111  and  112 . The thermal conductive resin layer  500  according to the present embodiment is not formed on the entire lower plate  300 , but can be composed of the first heat conductive resin layer  510  and the second heat conductive resin layer  520  so as to correspond to the portion of the battery cell  110  where heat generation is excessive. Through this structure, the cooling and heat dissipation performance can be increased while saving raw materials. 
     Further, the thermal conductive resin layer formed on the entirety of the lower plate  300  with respect to the battery cell  110  having a large difference in the degree of heat generation for each portion is difficult to eliminate the temperature deviation between the portions of the battery cells  110 . Unlike the same, since the battery module  100  according to the present embodiment includes the first thermal conductive resin layer  510  and the second thermal conductive resin layer  520 , heat dissipation can be effectively performed at both end parts of the battery cell  110  where heat generation is excessive, and the temperature deviation between the portions of one battery cell  110  can be minimized. Since the temperature deviation between the respective portions of the battery cell  110  ultimately causes a decrease in the performance of the battery module  100 , the first thermal conductive resin layer  510  and the second thermal conductive resin layer  520  according to the present embodiment may contribute to improving the performance and lifespan of the battery module. 
     At this time, referring to  FIGS.  1  to  3    again, in the conventional battery module  10 , a thermal conductive resin is injected via an injection hole  30 H to form a thermal conductive resin layer  50  between the lower surface of the battery cell stack  20  and the mono frame  30 , and therefore, it is difficult to precisely form the thermal conductive resin layer  50 . Specifically, the thermal conductive resin may be excessively injected over a predetermined amount due to clearance of parts inside the battery module. Further, with such an injection method, it is difficult to form the first thermal conductive resin layer  510  and the second thermal conductive resin layer  520  spaced apart from each other as in the present embodiment. 
     Unlike the same, since the thermal conductive resin layer  500  according to the present embodiment is formed by applying the thermal conductive resin onto the lower plate  300 , the possibility of excessively using the thermal conductive resin is low. Further, it has the advantage of being able to freely design and configure the thermally conductive resin layer as in the first thermal conductive resin layer  510  and the second thermal conductive resin layer  520 . Further, since this is not an injection method, it is advantageous for uniformly forming the thickness of the thermal conductive resin layer  500 . In addition, since the lower plate  300  is formed in a plate shape, it is easy to uniformly apply the thermal conductive resin up to the edge part thereof. 
     Meanwhile, although not specifically shown in the figure, an insulating film or the like may be disposed on the lower plate  300  between the first thermal conductive resin layer  510  and the second thermal conductive resin layer  520 . 
     Next, advantages of the lower plate  300  and the module frame  400  according to the present embodiment will be described with reference to  FIG.  8    and the like. 
       FIG.  8    is a perspective view of a module frame according to a comparative example of the present disclosure. 
     Referring to  FIG.  8   , a module frame structure in which an upper frame  40   a  and a lower frame  40   b  are combined may be proposed as a comparative example of the present disclosure. Both the upper frame  40   a  and the lower frame  40   b  may have side wall parts, wherein the upper frame  40   a  may form an n-shape in the cross-section, and the lower frame  40   b  may form a u-shape in the cross section. As described above, since the lower plate  300  according to the present embodiment is configured in a plate shape, it is easy to uniformly apply the thermal conductive resin up to the edge part. On the other hand, since the lower frame  40   b  according to the comparative example has two side wall parts facing upward, such side wall parts may become interfering factors in the process of applying the thermal conductive resin. 
     Further, when the upper frame  40   a  and the lower frame  40   b  are joined by a method such as welding, the joined part is located at the center of the side surface. In such joining, the thickness, squareness, width between the side wall parts, etc. of the frame must be precisely controlled without errors so that the side wall parts of the upper frame  40   a  and the side wall parts of the lower frame  40   b  can come into contact with each other. Otherwise, the side wall part of the upper frame  40   a  and the side wall part of the lower frame  40   b  do not come into contact with each other and thus are likely to be misaligned. In order to prevent this misalignment, the thickness of the upper frame  40   a  and the lower frame  40   b  must be increased, which is not favorable in terms of space efficiency or battery capacity of the battery module. On the other hand, as shown in  FIG.  5   , the first and second side surface parts  410  and  420  of the module frame  400  according to the present embodiment are advantageous for abutting on the plate-shaped lower plate  300  formed in a widely supporting structure. In addition, the risk of misalignment with respect to the plate-shaped lower plate  300  is low and thus the thickness of the module frame  400  can be thinly formed, which is advantageous in terms of space efficiency or battery capacity of the battery module. 
     Further, if the joining portion between the upper frame  40   a  and the lower frame  40   b  is located in the center of the side surface, the internal battery cells and the like are likely to be damaged by the penetration of the laser when laser welding or the like is performed. On the other hand, according to the present embodiment, since the first and second edge parts  310  and  320  of the lower plate  300  are weld-joined to the first and second side surface parts  410  and  420 , respectively, welding can be performed so to not to be penetrated by a laser. 
     Next, a mounting part according to an embodiment of the present disclosure will be described with reference to  FIG.  9    and the like. 
       FIG.  9    is a perspective view of a lower plate according to an embodiment of the present disclosure. Specifically, the lower plate included in the battery module of  FIG.  5    is shown in an enlarged manner. 
     Referring to  FIGS.  5  and  9   , the lower plate  300  according to the present embodiment may include a mounting part  300 M, and such a mounting portion  300 M may be formed on the first edge part  310  and the second edge part  320  of the lower plate  300  facing each other. The number of mounting portions  300 M is not particularly limited, and as shown in the figure, it can be configured by a plurality of numbers for each of the first and second edge parts  310  and  320 . 
     The battery module  100  according to the present embodiment may be gathered by a plurality of numbers to form a battery pack, and each battery module  100  can be fixed to a structure such as a pack frame (not shown) of the battery pack via a mounting part  300 M. Specifically, a mounting hole  300 H is formed in the mounting part  300 M, and the mounting part  300 M may be extended in parallel to one surface of the lower plate  300 . A fastening structure such as a bolt and a nut is applied between the mounting hole  300 H and the pack frame, so that the battery module  100  can be fixed to the pack frame. 
     Referring to  FIGS.  1  and  2    again, in the case of the conventional battery module  10 , it is difficult to provide the mounting part  70 M and the mounting hole  70 H to the mono frame  30  or the like, so that there is no choice but to form the mounting part  70  on the end plate  70 . The lower plate  300  of the plate-shaped structure according to the present embodiment can form the mounting part  300 M only by cutting from the plate material serving as the base material, while in order to form the mounting part  70 M on the mono frame  30  or the like, a complicated process such as bending, additional molding or joining is inevitably required. Thereby, in the conventional battery module  10 , it is common to form a mounting part  70 M on the end plate  70  instead of the mono frame  30  or the like. After all, the conventional mounting part  70 M was formed only in both end parts of the end plate  70 , that is, in a restricted portion called four corners with respect to the battery module  10 , and the number thereof is also inevitably restricted. Unlike the same, the plate-shaped lower plate  300  according to the present embodiment easily forms the mounting part  300 M, and the position or number of the mounting parts  300 M can be set more freely. As an example, the number of mounting parts  300 M can be increased and thus, the degree of fixing of the battery module  100  can be increased. In the design of the battery module  100  and the battery pack including the same, the position of the mounting part  300 M can be adjusted to reduce the restrictions. Further, the shape of the end plate  700  can be simplified, and free design is possible. 
     Next, a compression pad section according to an embodiment of the present disclosure will be described with reference to  FIG.  9    and the like. 
     The battery module  100  according to an embodiment of the present disclosure may further include a compression pad section  600  surrounding the thermal conductive resin layer  500 . Specifically, the first compression pad section  610  surrounding the first thermal conductive resin layer  510  and the second compression pad section  620  surrounding the second thermal conductive resin layer  520  may be provided. More specifically, on the lower plate  300 , the first compression pad section  610  may be disposed so as to surround four sides of the first thermal conductive resin layer  510 , and a second compression pad section  620  may be disposed so as to surround four sides of the second thermal conductive resin layer  520 . 
     The compression pad section  600  including the first compression pad section  610  and the second compression pad section  620  may be a foam type pad including polyurethane (PU). 
     The positions of the first compression pad section  610  and the second compression pad section  620  are adjusted in advance to set a region, and a thermal conductive resin can be applied to the region to form a first thermal conductive resin layer  510  and a second thermal conductive resin layer  520 . The positions of the first compression pad section  610  and the second compression pad section  620  can be freely set, so that the horizontal or vertical length of each of the first thermal conductive resin layer  510  and the second thermal conductive resin layer  520  can be easily adjusted. In other words, the first compression pad section  610  and the second compression pad section  620  according to the present embodiment may function as a kind of guide member for adjusting the region to which the thermal conductive resin is applied. That is, since the first compression pad section  610  and the second compression pad section  620  are disposed in advance, it is possible to prevent the thermal conductive resin from being applied outside a predetermined region, so that the thermal conductive resin layer  500  can be precisely realized in a desired region. 
     Further, since the first compression pad section  610  and the second compression pad section  620  have a predetermined height, it is possible to prevent the injection amount of the thermal conductive resin from overflowing. In particular, in the lower plate  300  of the plate-shaped structure, the first compression pad section  610  and the second compression pad section  620  can prevent the thermal conductive resin from flowing beyond the first edge part  310  or the second edge part  320 . 
     Moreover, the first compression pad section  610  and the second compression pad section  620  include a material to be compressed. Thus, when the battery cell stack  200  is seated thereon, it can be compressed. This may help to make the battery cell stack  200  adhere to the first thermal1 conductive resin layer  510  and the second thermal conductive resin layer  520 , and ultimately, it may lead to an improvement in the fixing power to the battery cell  110  or an improvement in the heat transfer performance through the thermal conductive resin layer  500 . 
     Next, the advantages of dimensional stabilization of the battery module  100  according to an embodiment of the present disclosure will be described with reference to  FIG.  10    and the like. 
     First, referring to  FIGS.  4  to  6    again, the battery module  100  according to the present embodiment may further include a busbar frame  800  on which a busbar  810  and a terminal busbar  820  are mounted. 
     The busbar  810  and the terminal busbar  820  may be joined to the electrode leads  111  and  112  of the battery cells  110  in order to electrically connect the plurality of battery cells  110 . Specifically, the busbar frame  800  on which the busbar  810  and the terminal busbar  820  are mounted can be disposed on the front surface (x-axis direction) and the rear surface (−x-axis direction) of the battery cell stack  200 . The front surface (x-axis direction) and the rear surface (−x-axis direction) of the battery cell stack  200  correspond to the surfaces in the direction in which the electrode leads  111  and  112  of the battery cells  110  protrude. A lead slot may be formed in the busbar frame  800 , and the electrode leads  111  and  112  are bent after passing through the lead slot and joined to the busbar  810  or the terminal busbar  820 . As long as physical and electrical connection is possible, the joining method is not particularly limited, and weld-joining can be performed as an example. 
     Meanwhile, a slot may be formed in the busbar  810  or the terminal busbar  820 , and the slot may be located correspondingly to the lead slot of the busbar frame  800 . The electrode leads  111  and  112  passing through the lead slot may be bent via the slot of the busbar  810  or the slot of the terminal busbar  820 . 
     Meanwhile, a part of the terminal busbar  820  may be exposed to the outside of the battery module  100 . Specifically, an opening part may be formed in the end plate  700  or an insulating cover (not shown), so that a part of the terminal busbar  820  can be exposed as shown in  FIG.  4   . A part of the exposed terminal busbar  820  may be connected to another battery module or a battery disconnect unit (BDU) to realize a high voltage (HV) connection or the like. Here, the HV connection is a connection that serves as a power source for supplying power, and means a connection between battery cells or a connection between battery modules. 
       FIG.  10    is a front view of the battery module of  FIG.  4    as viewed along the −x axis on the yz plane. 
     Referring to  FIGS.  4  and  10   , the battery module  100  according to the present embodiment can secure stability for the height direction dimension by adjusting the application amount of the thermal conductive resin and controlling the thickness of the compression pad section  600 . 
     In the case of the conventional battery module  10  shown in  FIGS.  1  to  3   , in the injection process, the battery cell stack  20  may be pushed toward the upper surface of the mono frame  30  by the pressure of the thermal conductive resin, thereby affecting the dimensions of major parts such as terminal busbars. When such battery modules  10  are configured by a plurality of numbers and assembled into a battery pack, the battery modules  10  are connected to each other via a terminal busbar. At this time, if the deviation in the height direction dimension of the terminal busbar is large for each battery module  10 , there may be a problem that due to an increase in contact resistance, heat is generated or the voltage value becomes inaccurate. 
     On the other hand, in the battery module  100  according to the present embodiment, since the thermal conductive resin is applied to the lower plate  300  as described above, the thermal conductive resin layer  500  having a relatively constant thickness can be formed, and the battery cell stack  200  is not pushed in. Further, the thickness and the degree of compression of the compression pad section  600  can be calculated to ensure the dimension safety in the height direction of the battery module  100 . As an example of the height direction dimension, the height direction dimension h of the terminal busbar  820  may be considered. Considering the thickness of the thermal conductive resin layer  500  (corresponding to the application amount of the thermal conductive resin), the thickness of the compression pad section  600  and the degree of compression of the compression pad section  600 , the height dimension h of the terminal busbar  820  can be predicted for each battery module  100 , and the height direction dimension h of such a terminal busbar  820  can be stabilized so as to show a constant value. In other words, the battery module  100  according to the present embodiment can be easily stabilized so that the height direction dimension h of the terminal busbar for each product shows a constant value, through the method in which the thermal conductive resin is applied, the thickness control of the compression pad section, and the like. 
     Further, since the configuration of the lower plate  300  is also formed of a plate-shaped structure, processing of the bottom, which is the datum of the battery module  100 , is minimized, which can be helpful to ensure the dimensional stability in the height direction. 
       FIG.  11    is a perspective view showing a battery cell stack and a lower plate according to an embodiment of the present disclosure.  FIG.  12   a    is a cross-sectional view taken along the cutting line A-A′ of  FIG.  11   .  FIG.  12   b    is a cross-sectional view taken along the cutting line B-B′ of  FIG.  11   . At this time,  FIGS.  12   a  and  12   b    show a state in which the battery cell stack is seated on the lower plate. 
     Referring to  FIGS.  7 ,  11 ,  12     a  and  12   b , as described above, a protrusion part  110   p  called a bat-ear may be formed in the battery cell  110  according to the present embodiment as described above. Specifically, two protrusion parts  110   p  may be formed at both end parts of the connection part  115  in the direction in which the electrode leads  111  and  112  protrude. 
     When the battery cell stack  200  in which the plurality of battery cells  110  are stacked is seated on the compression pad section  600  and the thermal conductive resin layer  500 , the protrusion part  110   p  may be located outside the compression pad section  600 . That is, the protrusion part  110   p  is located closer to one end part of the lower plate  300  than the compression pad section  600 , so that the compression pad section  600  can be disposed between the protrusion part  110   p  and the thermal conductive resin layer  500 . Specifically, any one of the protrusion parts  110   p  may be located closer to one end of the lower plate in the direction in which the electrode leads  111  protrude than the first compression pad section  610 . The other protrusion part  110   p  may be located closer to the other end of the lower plate in the direction in which the electrode lead  112  protrudes than the second compression pad section  620 . Here, the both end parts of the lower plate  300  may refer to end parts in contact with the first edge part  310  and the second edge part  320 . 
     Since the protrusion part  110   p  of the battery cell  110  has a protruding form, there may be a problem in that the portion is damaged when the battery cell stack is seated. At this time, the compression pad section  600  according to the present embodiment is located on the lower plate  300 , so that a space in which the protrusion part  110   p  of the battery cell  110  can be located can be naturally provided. Therefore, it is possible to prevent problems such as damage to the battery cells  110  including the protrusion part  110   p  when the battery cell stack  200  is seated. For this purpose, the thicknesses t31 and t32 of the compression pad section  600  according to the present embodiment may be thicker than the protrusion thickness t1 of the protrusion part  110   p . Specifically, both the thickness t31 of the first compression pad section  610  and the thickness t32 of the second compression pad section  620  may be thicker than the protrusion thickness t1 of the protrusion part  110   p . Here, the protrusion thickness t1 of the protrusion part  10   p  may mean a length at which the protrusion part  110   p  protrudes from the connection part  115  of the battery cell  110 . 
       FIG.  13    is a perspective view showing a lower plate  300   a  according to a modified embodiment of the present disclosure.  FIG.  14   a    is a cross-sectional view taken along the cutting line C-C′ of  FIG.  13   , and  FIG.  14   b    is a cross-sectional view taken along the cutting line D-D′ of  FIG.  13   . At this time,  FIGS.  14   a  and  14   b    show a state in which the battery cell stack is seated on the lower plate. 
     Referring to  FIGS.  7 ,  13 ,  14     a  and  14   b , the lower plate  300   a  according to a modified embodiment of the present disclosure may include stepped part  300 S formed at both end parts. Specifically, the stepped part  300 S may be formed at both end parts of the lower plate  300   a  in both directions in which the electrode leads  111  and  112  of the battery cells  110  protrude. Here, the stepped part  300 S may mean a portion of the lower plate  300   a  that is thinner than other portions. Here, the both end parts of the lower plate  300   a  may refer to end parts in contact with the first edge part  310  and the second edge part  320 . 
     When the battery cell stack  200  in which the plurality of battery cells  110  are stacked is seated on the compression pad section  600  and the thermal conductive resin layer  500 , the protrusion part  110   p  may be located on the stepped part  300 S. Specifically, the protrusion part  110   p  located on the outside of the compression pad section  600  may be located above the stepped part  300 S and spaced apart from the stepped part  300 S. Any one of the protrusion parts  110   p  is located on any one of the stepped parts  300 S, and another protrusion part  110   p  may be located on the other stepped part  300 S. 
     As the stepped part  300 S is formed on the lower plate  300   a  according to the present embodiment, the thickness t31 and t32 of the compression pad section  600  may be thinner than the protrusion thickness t1 of the protrusion part  110   p . That is, both the thickness t31 of the first compression pad section  610  and the thickness t32 of the second compression pad section  620  may be thinner than the protrusion thickness t1 of the protrusion part  110   p . By providing the stepped part  300 S, even if the thicknesses t31 and t32 of the compression pad section  600  and the thicknesses t21 and t22 of the thermal conductive resin layer  500  are thinly formed, a space in which the protrusion part  110   p  of the battery cell  110  can be located may be provided. Considering the thicknesses t31 and t32 of the compression pad section  600 , the thicknesses t21 and t22 of the thermal conductive resin layer  500 , and the protrusion thickness t1 of the protrusion part  110   p , the step depth of the stepped part  300 S may be set. Here, the step depth may mean a difference between the thickness of the stepped part  300 S and the thickness of the other lower plate  300   a  on which the stepped part  300 S is not formed. 
     Meanwhile, referring back to  FIGS.  12   a ,  12   b ,  14   a  and  14   b   , the thicknesses t21 and t22 of the thermal conductive resin layer  500  are equal to or thinner than the thicknesses t31 and t32 of the compression pad section  600 . Specifically, the thickness t21 of the first thermal conductive resin layer  510  may be equal to or thinner than the thickness t31 of the first compression pad section  610 , and the thickness t22 of the second thermal conductive resin layer  520  may be equal to or thinner than a thickness t32 of the second compression pad section  620 . 
     As described above, the first compression pad section  610  and the second compression pad section  620  can prevent the injection amount of the heat conductive resin from overflowing and can be compressed according to the seating of the battery cell stack  200 . That is, the thicknesses t21 and t22 of the thermal conductive resin layer  500  may be equal to or thinner than the thicknesses t31 and t32 of the compression pad section  600 , wherein the compression pad section  600  may be compressed due to the battery cell stack  200 , and the battery cell stack  200  may be in close contact with the thermal conductive resin layer  500 . 
     Even though the terms indicating directions such as upper, lower, left, right, front and rear directions are used in the present embodiments, it would be obvious to those skilled in the art that these merely represent relative positions for convenience in explanation and may vary depending on a position of an observer, a position of an object, or the like. 
     The one or more battery modules according to the present embodiments described above can be mounted together with various control and protection systems such as a battery management system (BMS) and a cooling system to form a battery pack. 
     The battery module or the battery pack can be applied to various devices. Specifically, these devices can be applied to vehicle means such as an electric bicycle, an electric vehicle, a hybrid vehicle, but the present disclosure is not limited thereto and can be applied to various devices that can use the secondary battery. 
     Although the preferred embodiments of the present disclosure have been described in detail above, the scope of the present disclosure is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concepts of the present disclosure defined in the following claims also falls within the spirit and scope of the present disclosure. 
     DESCRIPTION OF REFERENCE NUMERALS 
     
         
         
           
               200 : battery cell stack 
               300 : lower plate 
               400 : module frame 
               500 : thermal conductive resin layer 
               600 : compression pad section