Patent Publication Number: US-2022216537-A1

Title: Battery Module and Battery Pack Including the Same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a national phase entry under 35 U.S.C. § 371 of International Application No. PCT/KR2020/008073, filed Jun. 22, 2020, published in Korean, which claims the benefit of Korean Patent Application No. 10-2019-0125308 filed on Oct. 10, 2019 with the Korean Intellectual Property Office, the disclosures of which are incorporated herein by reference in their entireties. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to a battery module and a battery pack including the same, and more particularly, to a battery module having a simplified structure, and a battery pack including the same. 
     BACKGROUND ART 
     A secondary battery has attracted much attention as an energy source in various products such as a mobile device and an electric vehicle. The secondary battery is a potent energy resource that can replace the use of existing products using fossil fuels, and is in the spotlight as an environment-friendly energy source because it does not generate by-products due to energy use. 
     Recently, along with a continuous rise of the necessity for a large-capacity secondary battery structure, including the utilization of the secondary battery as an energy storage source, there is a growing demand for a battery pack of a multi-module structure which is an assembly of battery modules in which a plurality of secondary batteries are connected in series/parallel. 
     Such a battery module includes a battery cell stack in which a plurality of battery cells are stacked, a frame accommodating the battery cell stack, a busbar frame formed at each of both ends of the battery cell stack, an end plate formed outside the busbar frame and an insulating plate formed inside the end plate. 
       FIG. 1  is an exploded perspective view illustrating a module structure of a battery module according to the related art.  FIG. 2  is a schematic cross-sectional view illustrating assembled components when the battery module according to the related art is assembled in a battery pack. 
     Referring to  FIG. 1 , the battery module according to the related art includes a battery cell  10  stack, a busbar frame  20  covering front and rear surfaces of the battery cell  10  stack, an upper plate  21  connecting the busbar frame  20  at an upper end of the battery cell  10  stack, a frame  30  accommodating the battery cell  10  stack, the busbar frame  20 , and the upper plate  21 , and formed of a metal, a thermally conductive resin layer  11  formed between the frame and a lower surface of the battery cell stack, an insulation cover  40  formed on the outer side of the busbar frame  20 , and end plates  50  formed of a metal material on the outer side of the insulation cover  40 . 
     In this case, the frame  30  covers the upper, lower, left, and right surfaces of the battery cell  10  stack and end plates  50  are formed so as to cover the front and rear surfaces of the battery cell  10  stack, and as a result, the battery module has a structure in which a metal frame surrounds six surfaces of the battery cell  10  stack, and the thermally conductive resin layer  11  is separately inserted between the lower surface of the battery cell  10  stack and the metal frame to cool the battery cell  10 . 
     In this way, because the metal frame surrounds the six surfaces of the battery cell  10  stack and the thermally conductive resin layer  11  is separately inserted thereto, the weight of the battery module becomes relatively heavier. And as illustrated in  FIG. 2 , the thermally conductive resin layer  11  and the frame  30  are located between (i) a heat sink  32  formed in the battery pack and a thermally conductive layer  31  formed on an upper side of the heat sink  32  and (ii) the battery cell  10  stack, so that a cooling path becomes complicated and cooling performance decreases. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Technical Problem 
     It is an object of the present disclosure to provide a battery module having a structure capable of reducing a weight and reducing costs, and a battery pack including the same. 
     It is another object of the present disclosure to provide a battery module having a structure capable of improving a cooling performance, and a battery pack including the same. 
     Technical problems to be solved by the present disclosure are not limited to the above-mentioned technical problems, and other technical problems, which are not mentioned above, may be clearly understood from the following descriptions by those skilled in the art to which the present disclosure pertains. 
     Technical Solution 
     In order to realize the above object, according to one embodiment of the present disclosure, there is provided battery module and a battery pack including the same include: a battery cell stack in which a plurality of battery cells are stacked; an insulation plate covering a front surface or a rear surface of the battery cell stack; a busbar frame formed between the battery cell stack and the insulation plate; a sensing member connected to the busbar frame on an upper side of the battery cell stack; and side surface plates covering respective side surface of the battery cell stack, wherein each of the side surface plates includes a mounting part formed on an outer surface thereof, wherein a lower surface of the battery cell stack is opened, and wherein outermost battery cells of the plurality of battery cells and the side surface plates are coupled to each other, respectively, and the insulation plate is coupled with the busbar frame or at least one of the side surface plates to fix the plurality of battery cells forming the battery cell stack. Further, a thermally conductive layer contacting the lower surface of the battery cell stack and a heat sink located on a lower side of the thermally conductive layer are included. 
     The battery module may further include an upper plate located on the upper side of the sensing member to cover an upper surface of the battery cell stack and the sensing member. 
     The upper plate may be formed of a plastic. 
     The upper plate may be formed of a film. 
     Each of the side surface plates may be formed of a metal. 
     The insulation plate may be formed of a plastic. 
     The battery cell stack and the side surface plates may be coupled to each other by an adhesive agent. 
     The battery module may further include a lower cover covering the lower surface of the battery cell stack and the lower cover may be formed of a film. 
     In at least one of the side surface plates, the mounting part is formed of first, second, and third mounting parts, each of the first, second, and third mounting parts includes a coupling hole formed by passing through upwards and downwards, and the battery cell stack may be mounted through the coupling holes. 
     Advantageous Effects 
     A battery module and a battery pack comprising the same according to an embodiment of the present disclosure provide effects capable of reducing a weight of the battery module and saving a process cost incurred in a process of manufacturing the battery module, by forming a simple structure fixing a plurality of battery cells by using an insulation plate and a side surface plate instead of an existing frame. 
     Further, according to an embodiment of the present disclosure, a battery module and a battery pack including the same are formed such that the plurality of battery cells and a thermally conductive layer formed in the battery pack contact each other whereby a cooling path is simplified to improve the cooling performance. 
     The effects of the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view illustrating a module structure of a battery module according to the related art; 
         FIG. 2  is a schematic cross-sectional view illustrating assembled components when the battery module according to the related art is assembled in a battery pack; 
         FIG. 3  is an exploded perspective view illustrating a battery module according to an embodiment of the present disclosure; 
         FIG. 4  is a schematic cross-sectional view illustrating assembled components when the battery module according to an embodiment of the present disclosure is assembled in a battery pack; 
         FIG. 5  is an exploded perspective view illustrating the battery module having an upper plate according to a modified embodiment of the present disclosure; and 
         FIG. 6  is an exploded perspective view illustrating the battery module having a lower cover according to a modified embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     It should be appreciated that the exemplary embodiments, which will be described below, are illustratively described to help understand the present disclosure, and the present disclosure may be variously modified to be carried out differently from the exemplary embodiments described herein. However, in the description of the present disclosure, the specific descriptions and illustrations of publicly known functions or constituent elements will be omitted when it is determined that the specific descriptions and illustrations may unnecessarily obscure the subject matter of the present disclosure. In addition, to help understand the present disclosure, the accompanying drawings are not illustrated based on actual scales, but parts of the constituent elements may be exaggerated in size. 
     As used herein, terms such as first, second, and the like may be used to describe various components, and the terms are used only to discriminate one component from another component. 
     Further, the terms used herein are used only to describe exemplary embodiments, and are not intended to limit the present disclosure. A singular expression includes a plural expression unless they have definitely opposite meanings in the context. It should be understood that the terms “comprise”, “include”, and “have” as used herein are intended to designate the presence of stated features, numbers, steps, constitutional elements, components or combinations thereof, but it should be understood that they do not preclude a possibility of existence or addition of one or more other features, numbers, steps, constitutional elements, components or combinations thereof. 
     Hereinafter, a battery module according to one embodiment of the present disclosure will be described with reference to  FIGS. 3 and 4 . 
       FIG. 3  is an exploded perspective view illustrating the battery module according to an embodiment of the present disclosure.  FIG. 4  is a schematic cross-sectional view illustrating assembled components when the battery module according to an embodiment of the present disclosure is assembled in a battery pack. 
     Referring to  FIGS. 3 and 4 , a battery module according to an embodiment of the present disclosure includes a battery cell stack in which a plurality of battery cells  100  are stacked, an insulation plate  300  covering front and rear surfaces of the battery cell stack, a busbar frame  200  formed between the battery cell stack and the insulation plate, a sensing member  210  connecting the busbar frame on the upper side of the battery cell stack, and side surface plates  400  covering both side surfaces of the battery cell stack, wherein a mounting part  410  is formed on an outer surface of the side surface plate, and the insulation plate  300  is coupled to the busbar frame  200  or the side surface plate  400  to fix the plurality of battery cells. 
     The battery cell  100  may be a secondary battery, and may be configured of a pouch type secondary battery. The battery cell  100  may be formed of a plurality of cells and the plurality of battery cells  100  may be mutually stacked so as to be electrically connected to each other, and thus the battery cell stack may be formed. Each of the plurality of battery cells may include an electrode assembly, a battery case, and an electrode lead (not illustrated) protruding from an electrode assembly. 
     Each of busbar frames  200  is formed on front and rear surfaces of the battery cell stack. The busbar frames  200  may be formed to cover the front and rear surface of the battery cell stack so as to electrically connect the electrode leads of a plurality of battery cells  100 . 
     The sensing member  210  connects the busbar frame  200  formed on the front surface of the battery cell stack and the busbar frame  200  formed on the rear surface of the battery cell stack on the upper side of the battery cell stack. Each of the busbar frames  200  formed on the front and rear surfaces of the battery cell stack may be connected to each other through the sensing member  210 . 
     Each of the insulation plates  300  is formed on the outer side of the busbar frames with respect to the battery cell stack so as to cover the front and rear surfaces of the battery cell stack. The insulation plates  300  are formed so as to cover the busbar frame  200  to interrupt the busbar frame  200  from being electrically connected to the outside. According to an embodiment of the present disclosure, the insulation plate  300  may be formed of plastic having an insulation function. 
     The side surface plates  400  are formed so as to cover both side surfaces of the battery cell stack. According to an embodiment of the present disclosure, the side surface plate  400  may be formed of a metal, and outermost battery cells formed on the opposite sides of the battery cell stack and the side surface plates  400  of the opposite sides thereof may be coupled to each other by an adhesive agent, respectively, and may be also pressed to be coupled to each other. However, the method for coupling the battery cell stack and the side surface plate is not limited thereto, but it is possible to couple the battery cell stack and the side surface plate in various ways. 
     The mounting part  410  may be formed on the outer surface of the side surface plate  400  to couple the battery module according to the embodiment of the present disclosure to the battery pack through the mounting part  410 . The mounting part  410 , as illustrated in  FIG. 3 , may include a first mounting part  411  formed at one side end of the side surface plate  400 , a second mounting part  412  formed at opposite end of the side surface plate  400 , and a third mounting part  413  formed at the center of the side surface plate. 
     Each of the mounting parts may include a coupling hole  410   a  formed to pass therethrough upwards and downwards. The first mounting part  411  may include a first coupling hole  411   a , the second mounting part  412  may include a second coupling hole  412   a , and a third mounting part  413  may include a third coupling hole  413   a . The battery module according to the embodiment of the present disclosure may be coupled to the battery pack through the coupling hole  410   a.    
     The insulation plate  300  is coupled to the busbar frame  200  or the side surface plate  400  to function to fix the plurality of battery cells  100  located in the interiors of plates. According to the embodiment of the present disclosure, the insulation plate  300  may be coupled to the busbar frame  200  or the side surface plate  400  through an adhesive agent. 
     In a battery module according to the related art, a frame covers the upper, lower, left, and right surfaces of a battery cell stack and end plates cover front and rear surfaces of the battery cell stack so that the weight of the battery module becomes relatively heavy, and it costs a lot to manufacture the frame and the end plates. However, the battery module according to the embodiment of the present disclosure may remove the conventional the frame and the end plates, and instead, may fix and protect the battery cell stack with only the insulation plate and the side surface plates, and thus the weight of the battery module may be reduced and costs for manufacturing the battery module may be reduced. 
     The battery module according to the embodiment of the present disclosure may be formed such that the lower surface of the battery cell  100  stack is opened. The fact that the lower surface of the battery cell  100  stack is opened means that the lower surface of the battery cell  100  stack is not covered by the frame or the plate as in the related art. Accordingly, when the battery module is installed in the battery pack, the lower surface of the battery cell stack may contact a thermally conductive layer  700  formed in the battery pack according to an embodiment of the present disclosure and may be connected to a heat sink  800  formed on the lower side of the thermally conductive layer  700  through the thermally conductive layer. 
     The thermally conductive layer  700  may be formed of a thermally conductive substance and the thermally conductive layer  700  may transfer heat generated from the plurality of battery cells  100  of the battery module to the outside of the battery module. The heat sink  800  contacts the thermally conductive layer  700  to emit heat transferred from the thermally conductive layer  700  to the to the outside through refrigerant flowing inside the heat sink  800 . 
     According to the related art, as illustrated in  FIG. 2 . heat generated from the battery cell has to sequentially pass through a thermally conductive layer, a frame, and a thermally conductive layer, and a heat sink to be emitted to the outside. However, in the battery module according to the embodiment of the present disclosure, because the thermally conductive resin and the frame are removed and the battery cell  100  directly contacts the thermally conductive layer  700  of the battery cell, heat generated in the battery cell  100  passes through only the thermally conductive layer  700  and the heat sink  800 , and thus a heat transfer path may be simplified to improve cooling performance. Further, because it is not necessary to use the thermally conductive resin, the weight of the battery module can be reduced and costs for manufacturing the battery module can be reduced. 
     Hereinafter, according to a modified embodiment of the present disclosure, a battery module having an upper plate will be described. 
       FIG. 5  is an exploded perspective view illustrating the battery module having an upper plate according to a modified embodiment of the present disclosure. 
     Referring to  FIG. 5 , the battery module according to a modified embodiment of the present disclosure may further include an upper plate  500  located on the upper side of a sensing member and covering an upper surface of a battery cell  100  stack and a sensing member. 
     The upper plate  500  according to the modified embodiment of the present disclosure may be formed of plastic that is lighter than a metal and may be also formed of a film that is lighter than plastic. Accordingly, the weight of the battery module may become light as compared with the upper side structure of the frame according to the related art, which is formed of a metal, to also protect electric components of the battery module on the upper side of the battery cell stack through the upper plate  500 . 
     The contents except for the above-mentioned contents are the same as those described for the battery module and the battery pack according to one embodiment of the present disclosure. 
     Hereinafter, according to a modified embodiment of the present disclosure, a battery module having a lower cover will be described. 
       FIG. 6  is an exploded perspective view illustrating the battery module having the lower cover according to the modified embodiment of the present disclosure. 
     Referring to  FIG. 6 , the battery module according to the modified embodiment may further include a lower cover  600  covering the lower surface of the battery cell  100  stack. According to a modified embodiment of the present disclosure, the lower cover  600  may be formed of a film that is lighter than a metal. Accordingly, the weight of the battery module may become light as compared with the upper side structure of the frame according to the related art, which is formed of a metal to prevent in advance an unexpected damage that may be caused on the lower surface of the battery cell stack when the battery module is assembled to the battery pack through the lower cover  600 . The contents except for the above-mentioned contents are the same as those described for the battery module and the battery pack according to one embodiment of the present disclosure. 
     The above-mentioned battery module may be included in the battery pack. The battery pack may be a structure, to which a battery management system (BMS) that collectively manages the temperatures, the voltages, or the like of the batteries of one or more battery modules according to the present disclosure and a cooling device are added, such that the BMS and the cooling device are packed. A plurality of battery modules may be installed in the battery pack, and lower surfaces of the battery cell stacks formed in the plurality of battery modules contact a thermally conductive layer formed in the battery pack, so that heat generated in the battery cell can be emitted to the outside through a heat sink formed to contact the thermally conductive layer. 
     The battery pack can be applied to various devices. Such a device may be applied to a vehicle such as an electric bicycle, an electric vehicle, or a hybrid vehicle, but the present disclosure is not limited thereto, and is applicable to various devices that can use a battery module, which also belongs to the scope of the present disclosure. 
     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 of those skilled in the art using the basic concepts of the present disclosure defined in the following claims also belong to the scope of rights. 
     DESCRIPTION OF REFERENCE NUMERALS 
     
         
         
           
               100 : battery cell 
               200 : busbar frame 
               210 : sensing member 
               300 : insulation plate 
               400 : side surface plate 
               410 : mounting part 
               411 ,  412 ,  413 : first, second, third mounting part 
               411   a ,  412   a ,  413   a : first, second, third coupling hole 
               500 : upper plate 
               600 : lower cover 
               700 : thermally conductive layer 
               800 : heat sink