Battery pack

Abstract

The present invention relates to a battery module with a simplified structure and to a battery pack including it. The battery module comprises: a battery cell stack composed of multiple stacked cells; insulating plates covering the front and rear surfaces of the cell stack; busbar frames formed between the cell stack and each of the insulating plates; a sensing element disposed on the cell stack and connecting the busbar frames to each other; and side plates covering the opposite side surfaces of the cell stack. Mounting parts are formed on these side plates; the cell stack is open on its lower surface; the outermost cells of the stack are coupled to the side plates, respectively, and the insulating plates are coupled to the busbar frames or to the side plates, thereby securing the multiple cells that constitute the stack.

Description

[TECHNICAL FIELD] Cross Citation with Related Application(s)

[0001] This application claims the priority of Korean Patent Application No. 10-2019-0125308 filed on October 10, 2019 with the Korean Intellectual Property Office.

[0002] The present disclosure relates to a battery pack including at least one battery module, and more particularly, to a battery pack having a simplified structure.[BACKGROUND ART]

[0003] 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 byproducts due to energy use.

[0004] 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.

[0005] 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.

[0006] 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.

[0007] 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.

[0008] 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.

[0009] 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 whereby the weight of the battery module relatively becomes heavier, and as illustrated in FIG. 2, a heat sink 32 formed in the battery pack, the thermally conductive resin layer 11 and the frame 30 are located between the 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 the battery cell 10 stack, so that a cooling path becomes complicated and cooling performance decreases.

[0010] Further prior art is described in WO 2019 / 182251 A1, KR 2019 0027096 A1, WO 2018 / 159928 A1, US 2018 / 108881 A1, US 2015 / 303425 A1 and US 2014 / 045027 A1.[DETAILED DESCRIPTION OF THE INVENTION] [TECHNICAL PROBLEM]

[0011] It is an object of the present disclosure to provide a battery pack including a battery module having a structure capable of reducing a weight and reducing costs.

[0012] It is another object of the present disclosure to provide a battery pack including a battery module having a structure capable of improving a cooling performance.

[0013] 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]

[0014] These objects are accomplished by a battery pack comprising the features of patent claim 1.

[0015] Dependent claims are directed on features of preferred embodiments of the invention.[ADVANTAGEOUS EFFECTS]

[0016] A battery pack comprising a battery module according to an embodiment of the present disclosure provides effects capable of reducing the 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.

[0017] 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.

[0018] 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]

[0019] 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. [DETAILED DESCRIPTION OF THE EMBODIMENTS]

[0020] 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.

[0021] 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.

[0022] 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.

[0023] Hereinafter, a battery module according to one embodiment of the present disclosure will be described with reference to FIGS. 3 and 4.

[0024] 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 is assembled in a battery pack according to an embodiment of the present disclosure.

[0025] 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 each 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.

[0026] The battery cell 100 is 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 are 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.

[0027] Each of busbar frames 200 is formed on front and rear surfaces of the battery cell stack. The busbar frames 200 are 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.

[0028] 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 is connected to each other through the sensing member 210.

[0029] 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.

[0030] The side surface plates 400 are formed so as to cover the 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.

[0031] 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.

[0032] Each of the mounting parts may include a coupling hole 410a formed to pass therethrough upwards and downwards. The first mounting part 411 may include a first coupling hole 411a, the second mounting part 412 may include a second coupling hole 412a, and a third mounting part 413 may include a third coupling hole 413a. The battery module according to the embodiment of the present disclosure may be coupled to the battery pack through the coupling hole 410a.

[0033] The insulation plates 300 are coupled to the busbar frames 200 or the side surface plates 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 plates 300 may be coupled to the busbar frames 200 or the side surface plates 400 through an adhesive agent.

[0034] In a battery module according to the related art, a frame covering the upper, lower, left, and right surfaces of a battery cell stack and end plates covering 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 frame and the end plates, and instead, fixes and protects 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.

[0035] The battery module according to the embodiment of the present disclosure is 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 contacts a thermally conductive layer 700 formed in the battery pack according to an embodiment of the present disclosure and is connected to a heat sink 800 formed on the lower side of the thermally conductive layer 700 through the thermally conductive layer.

[0036] The thermally conductive layer 700 is formed of a thermally conductive substance and the thermally conductive layer 700 transfers 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.

[0037] 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.

[0038] Hereinafter, according to a modified embodiment of the present disclosure, a battery module having an upper plate will be described.

[0039] FIG. 5 is an exploded perspective view illustrating the battery module having an upper plate according to a modified embodiment of the present disclosure.

[0040] Referring to FIG. 5, the battery module according to a modified embodiment of the present disclosure further includes 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.

[0041] The upper plate 500 according to the modified embodiment of the present disclosure is 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.

[0042] 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.

[0043] The above-mentioned battery mo dule is 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.

[0044] 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.[Description of Reference Numerals]

[0045] 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 411a, 412a, 413a: first, second, third coupling hole 500: upper plate 700: thermally conductive layer 800: heat sink

Claims

1. A battery pack comprising: a plurality of battery modules, each module, comprising: a battery cell stack in which a plurality of battery cells (100) are stacked; insulation plates (300) covering front and rear surfaces of the battery cell stack; a busbar frame (200) formed between the battery cell stack and the insulation plates (300); a sensing member (210) connecting the busbar frames (200) on the upper side of the battery cell stack; and side surface plates (400) each covering a side surface of the battery cell stack, respectively, wherein mounting parts (410) are formed on an outer surface of the side surface plates (400), wherein a lower surface of the battery cell stack is opened, and wherein an outermost battery cell (100) of the battery cell stack and the side surface plates (400) are coupled to each other, and the insulation plates (300) are coupled with the busbar frames (200) or the side surface plates (400) to fix the plurality of battery cells (100) forming the battery cell stack, wherein the battery pack is a structure, to which a battery management system (BMS) that collectively manages the temperatures, the voltages, or the like of the batteries of the battery modules and a cooling device are added, such that the BMS and the cooling device are packed, wherein 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.

2. The battery pack of claim 1, further comprising: an upper plate (500) located on the upper side of the sensing member (210) to cover an upper surface of the battery cell stack and the sensing member (210).

3. The battery pack of claim 2, wherein the upper plate (500) is formed of plastic or a film.

4. The battery pack of claim 1, wherein the side surface plates (400) are formed of metal.

5. The battery pack of claim 1, wherein the insulation plates (300) are formed of plastic.

6. The battery pack of claim 1, wherein the battery cell stack and the side surface plates (400) are coupled to each other by an adhesive agent.

7. The battery pack of claim 1, wherein the mounting part (410) is formed of first, second, and third mounting parts (411, 412, 413) and a coupling hole (411a, 411b, 411c) is formed upwards and downwards through each of the mounting parts (411, 412, 413).

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