Cooling device and battery cell stack including same

Abstract

The present invention provides a cooling device that is arranged in direct contact with the surface of a battery cell within a secondary battery module (or battery cell stack) and cools the battery cell by the flow of a refrigerant. The cooling device is formed using two members made of different materials with different thermal conductivities, thereby improving cooling performance and effectively preventing heat transfer, and also provides a battery cell stack that includes the cooling device. A battery cell stack according to various embodiments includes a plurality of battery cells, one or more cooling devices in contact with at least some of the plurality of battery cells, and a case that houses the plurality of battery cells and the one or more cooling devices, each of which includes a refrigerant flow path therein and is configured to cool at least some of the battery cells by a refrigerant flowing through the refrigerant flow path, and each of which includes a first surface and a second surface having different thermal conductivities.

Description

[Technical Field]

[0001] Various embodiments of the present disclosure relate to cooling devices and battery cell stacks including the same. [Background technology]

[0002] Secondary batteries are capable of charging and discharging and are widely used in portable mobile devices such as digital cameras, mobile phones, and laptops. In particular, in recent years, secondary batteries have been widely used not only in small devices such as portable electronic devices, but also in medium- to large-sized devices such as electric vehicles and energy storage systems (ESS) for driving and storing energy.

[0003] Such secondary batteries can be configured as a battery module in which a number of electrically connected cells are housed together inside a module case, and a number of such battery modules can be connected to form a battery pack.

[0004] However, when a stack of multiple secondary batteries (battery cells) or multiple secondary battery modules are densely packed in a small space, they may be vulnerable to thermal events. For example, if an event such as thermal runaway occurs in one battery cell, the event may spread to other battery cells. Such thermal transfer phenomena can cause serious problems such as fires or explosions. When multiple secondary battery modules are included in a host device such as a battery pack, battery rack, or power storage device, the fire, explosion, or other such event may spread widely to other secondary battery modules included in the host device.

[0005] Meanwhile, in the past, a method of placing a cooling device for cooling secondary batteries on the outside of a secondary battery module or at the bottom of the module case has been considered, but in recent years, as a measure to further improve the cooling performance of secondary batteries, a method has been considered in which the cooling device is placed in direct contact with the surface of the battery cells, allowing the refrigerant to flow inside the cooling device and directly exchange heat with the surface of the battery cells.

[0006] Such cooling devices are typically manufactured using metals with high thermal conductivity to increase the efficiency of heat exchange. Summary of the Invention [Problem to be solved by the invention]

[0007] When a direct cell surface water cooling method is applied, in which a cooling device is interposed between battery cells and the cooling device comes into direct contact with the surface of the battery cells for cooling, this method may be superior in terms of cooling efficiency. However, if an event such as thermal runaway occurs in a certain battery cell, the cooling device, which is made of a material with high thermal conductivity and is placed between each battery cell, may actually accelerate the heat transfer, increasing the possibility of serious problems such as fires or explosions.

[0008] Various embodiments of the present disclosure have been devised to solve at least some of the problems of the prior art as described above, and provide a cooling device that is arranged in direct contact with the surfaces of battery cells within a secondary battery module (or battery cell stack) and cools the battery cells by the flow of a refrigerant, and is formed using two members made of different materials with different thermal conductivities, thereby improving cooling performance and effectively preventing heat transfer, and a battery cell stack including the cooling device. [Means for solving the problem]

[0009] A battery cell stack according to various embodiments includes a plurality of battery cells, one or more cooling devices arranged to contact at least one of the plurality of battery cells, and a case that houses the plurality of battery cells and the one or more cooling devices, each of which includes a refrigerant flow path therein and is configured to cool at least one of the plurality of battery cells by a refrigerant flowing through the refrigerant flow path, and each of which includes a first surface and a second surface that forms another surface different from the first surface, and the first surface and the second surface may be made of materials having different thermal conductivities.

[0010] A cooling device used to cool a secondary battery according to various embodiments includes a first surface and a second surface facing in the opposite direction to the first surface, each having different thermal conductivities, the first surface being in contact with a first battery cell, and the second surface being in contact with a second battery cell adjacent to the first battery cell. The cooling device may also include a refrigerant flow path therein, and be configured to cool the first battery cell and the second battery cell by a refrigerant flowing through the refrigerant flow path. [Effects of the Invention]

[0011] According to various embodiments of the present disclosure, a cooling device and a battery cell stack with improved cooling efficiency can be provided.

[0012] Furthermore, even if an event such as thermal runaway occurs in a battery cell, safety can be improved by minimizing heat transfer to surrounding battery cells or other battery modules (or other battery cell stacks).

[0013] Furthermore, the same effect can be achieved without adding a separate component such as an insulating sheet to prevent the thermal transition phenomenon, and a secondary battery module (or battery cell stack) with improved energy density can be provided. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic exploded perspective view of a secondary battery module 10 according to an embodiment of the present disclosure. [Figure 2] 1 is a schematic cross-sectional view of a secondary battery module 10 according to an embodiment of the present disclosure. [Figure 3] FIG. 1 is a schematic perspective view illustrating the structure of a cooling device 300 according to an embodiment of the present disclosure. [Figure 4] 3 is a schematic cutaway cross-sectional view illustrating the flow of refrigerant inside a cooling device 300 according to an embodiment of the present disclosure. FIG. [Figure 5a] 1 is a schematic cross-sectional side view of a cooling device 300 according to an embodiment of the present disclosure. [Figure 5b] 1 is a schematic cross-sectional side view of a cooling device 300 according to an embodiment of the present disclosure. [Figure 5c] 1 is a schematic cross-sectional side view of a cooling device 300 according to an embodiment of the present disclosure. [Figure 5d] 1 is a schematic cross-sectional side view of a cooling device 300 according to an embodiment of the present disclosure. [Figure 6] FIG. 2 is a schematic cross-sectional view of a secondary battery module 10 according to another embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0015] Prior to a detailed description of the present invention, the terms and words used in the specification and claims should not be interpreted limitedly to their ordinary and dictionary meanings, but should be interpreted in terms and concepts that are consistent with the technical idea of ​​the present invention, based on the principle that the inventor can appropriately define the concepts of terms in order to best describe his or her invention. Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not fully represent the technical idea of ​​the present invention, and that there may be various equivalents and modifications that can replace them at the time of filing this application.

[0016] The same reference numbers or symbols in the drawings attached to this specification indicate parts or components that perform substantially the same functions. For ease of explanation and understanding, different embodiments may be described using the same reference numbers or symbols. In other words, even if components having the same reference numbers are shown in multiple drawings, it does not necessarily mean that all of the multiple drawings represent one embodiment.

[0017] In the following description, the singular includes the plural unless the context clearly dictates otherwise. Terms such as "comprise" or "comprise" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, and should be understood as not precluding the presence or possibility of addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0018] In addition, in the following description, expressions such as upper, top, lower, bottom, side, front, back, etc. are expressed based on the direction shown in the drawing, and it should be made clear in advance that they may be expressed differently if the direction of the object is changed.

[0019] Furthermore, in this specification and claims, terms including ordinal numbers such as "first," "second," etc. may be used to distinguish between components. Such ordinal numbers are used to distinguish between identical or similar components, and the use of such ordinal numbers should not be interpreted in a restrictive manner. For example, the order of use or arrangement of components combined with such ordinal numbers should not be interpreted in a restrictive manner. If necessary, each ordinal number may be used interchangeably.

[0020] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the concept of the present invention is not limited to the presented embodiments. For example, a person with ordinary skill in the art who understands the concept of the present invention (hereinafter referred to as "ordinary engineer") should be able to propose other embodiments that fall within the scope of the concept of the present invention by adding, changing, or deleting components, and these can also be considered to fall within the scope of the concept of the present invention. Note that the shapes and sizes of elements in the drawings may be exaggerated for clarity.

[0021] Fig. 1 is a schematic exploded perspective view of a secondary battery module 10 according to an embodiment of the present disclosure. Fig. 2 is a schematic cross-sectional view of the secondary battery module 10 according to an embodiment of the present disclosure.

[0022] Referring to Figures 1 and 2, a secondary battery module 10 according to various embodiments may include a plurality of battery cells 100, one or more cooling devices 300, and a case 200 that houses these components in an internal space.

[0023] The battery cells 100 (e.g., secondary batteries) may be arranged in a stacked configuration along one direction (e.g., a direction parallel to the Y axis in FIGS. 1 and 2) as shown in FIGS. 1 and 2.

[0024] Each battery cell 100 may include, for example, a pouch-type battery cell.

[0025] For example, a pouch-type battery cell can be formed by enclosing an electrode case in a pouch case made of a laminate sheet including a resin layer and a metal layer, and then heat-sealing the sealing portion of the pouch case. For example, the battery cell 100 can have a substantially rectangular sheet-like structure.

[0026] However, it goes without saying that the secondary battery cells 100 included in the secondary battery modules 10 according to various embodiments of the present disclosure are not necessarily limited to pouch-type battery cells, and various types of battery cells such as rectangular battery cells and cylindrical battery cells may be applied within the applicable scope of the embodiments described in this specification.

[0027] Although not specifically shown in the drawings, the battery cell 100 may include at least an electrode assembly including a first electrode (e.g., a positive electrode), a second electrode (e.g., a negative electrode), and a separator, a battery case (e.g., a pouch case), and an electrolyte. For example, each battery cell 100 may be electrically connected in series or parallel to other battery cells 100 via a structure such as a bus bar.

[0028] Meanwhile, a cooling device 300 (e.g., a cooling jacket) may be interposed between each battery cell 100 and / or between the battery cell 100 arranged at the outermost end of the secondary battery module 10 and the case 200.

[0029] For example, the plurality of battery cells 100 and the cooling device 300 may be alternately stacked in the case 200. Alternatively, the plurality of battery cells 100 and the cooling device 300 may be stacked and directly configured into a battery pack without being housed in the case 200.

[0030] In an embodiment, the cooling device 300 and the plurality of battery cells 100 may be arranged by a surface cooling method. For example, the cooling device 300 is stacked so as to face a large surface of the battery cells 100, and can exchange heat with the battery cells 100 in a state of direct contact with the large surface of the facing specific battery cell 100.

[0031] 1 shows that the battery cells 100 and the cooling devices 300 are alternately provided one by one, but if necessary, a plurality of battery cells 100 may be provided in a predetermined unit, and a battery cell unit may be provided between two cooling devices 300. As an example, each battery cell unit interposed between two cooling devices 300 may be defined as having a predetermined battery capacity (e.g., 150 Ah to 350 mA) by combining two or more battery cells 100. In another example, the battery cell unit may be defined as having a predetermined size (length, width, etc.).

[0032] In various embodiments, the cooling device 300 is positioned so as to be in direct contact with the battery cell 100 (e.g., inside the case 200 of the secondary battery module 10 or inside the pack case of the battery pack), thereby allowing at least one adjacent battery cell 100 to be more effectively cooled based on the refrigerant flowing inside the cooling device 300.

[0033] For example, when the cooling device 300 is interposed between two adjacent battery cells 100 (e.g., a first battery cell and a second battery cell), the cooling device 300 includes a first surface and a second surface facing in the opposite direction from the first surface, and can be in contact with the first battery cell through the first surface and in contact with the second battery cell through the second surface. For example, the second surface can form another surface of the cooling device 300 that is different from the first surface.

[0034] According to various embodiments of the present disclosure, the cooling device 300 may be configured such that the materials comprising the first and second surfaces have different thermal conductivities.

[0035] For example, in one cooling device 300, the thermal conductivity of the material constituting one side (i.e., the first surface) may be less than a predetermined value (e.g., less than 5 W / m·K, particularly 0.0001 W / m·K or more and less than 5 W / m·K), and the thermal conductivity of the material constituting the other side (i.e., the second surface) may be greater than or equal to a predetermined value (e.g., 10 W / m·K or more, particularly 10 W / m·K or more and less than 10,000 W / m·K).

[0036] In one example, a first surface of the cooling device 300 may be constructed from a non-metallic material, and a second surface facing away from the first surface may be constructed from a metallic material.

[0037] For example, the first surface may be made of a thermally conductive resin. For example, the first surface may be made of a material that has relatively lower thermal conductivity than the second surface but has adhesive properties. For example, the first surface may be made of a thermally conductive adhesive material that has adhesive properties and is made of at least one of silicone, urethane, and acrylic.

[0038] The cooling device 300 according to various embodiments may be formed by combining a first member 310 and a second member 320 formed of materials with different thermal conductivities.

[0039] For example, the cooling device 300 may be formed by joining a first member 310 made of a non-metallic material and a second member 320 made of a metallic material. In this case, the first member 310 may form a first surface made of a material with a relatively low thermal conductivity, and the second member 320 may form a second surface made of a material with a relatively high thermal conductivity.

[0040] In general, the cooling device 300 can cool the battery cells 100 by allowing heat exchange between the refrigerant flowing through the internal space (i.e., the refrigerant flow path) and the adjacent battery cells 100. For example, to improve heat exchange between the refrigerant and the battery cells 100, the entire area of ​​the cooling device 300 in contact with the battery cells 100 can be formed from a material with high thermal conductivity.

[0041] On the other hand, when a cooling device 300 with high thermal conductivity is interposed between the battery cells 100, the contact area between the cooling device 300 and the battery cells 100 is maximized, which is beneficial in terms of heat exchange for cooling. However, if an event such as thermal runaway occurs in a certain battery cell 100, the cooling device 300 with high thermal conductivity may further promote the phenomenon of thermal propagation.

[0042] According to various embodiments of the present disclosure, by configuring the materials constituting one side (first surface) and the other side (second surface) of a cooling device 300 interposed between battery cells 100 (or between the outermost, i.e., the outermost battery cell 100 and the case 200) to have different thermal conductivities, even if a thermal runaway event occurs in one of the battery cells in contact with one side of the cooling device 300, the promotion of heat transfer through the cooling device 300 to other battery cells in contact with the other side of the cooling device 300 can be minimized.

[0043] For example, the cooling device 300 according to various embodiments of the present disclosure can simultaneously achieve the cooling effect and the heat transfer prevention effect on the battery cell 100 without providing a separate heat insulating sheet.

[0044] Meanwhile, as shown in FIG. 2, each battery cell 100 may be in contact with a respective cooling device 300 (eg, a first cooling device and a second cooling device) on one side and the other side facing in opposite directions.

[0045] In this case, the thermal conductivity of the material constituting one surface (e.g., the first surface of the first cooling device) of a cooling device (e.g., the first cooling device) in contact with one side of the battery cell 100 and one surface (e.g., the second surface of the second cooling device) of another cooling device (e.g., the second cooling device) in contact with the other side of the battery cell 100 may be different from each other.

[0046] For example, if one surface of a first cooling device in contact with one side of a battery cell 100 is formed from a first member 310 having a relatively low thermal conductivity, one surface of a second cooling device in contact with the other side of the battery cell 100 may be formed from a second member 320 having a relatively high thermal conductivity.

[0047] Specifically, each of the entire battery cells 100 constituting the secondary battery module 10 may be arranged to contact at least one surface of the cooling device 300 formed of the second member 320 having high thermal conductivity. This allows each battery cell 100 to exchange heat with the refrigerant effectively through the second member 320 having high thermal conductivity.

[0048] For example, a cooling device 300 including at least one surface formed by a first member 310 with low thermal conductivity may be arranged on both sides of each of the entire battery cells 100 constituting the secondary battery module 10. For example, even if thermal runaway occurs in a certain battery cell 100, the first member 310 with low thermal conductivity can minimize the occurrence of heat transfer in either direction on both sides of the battery cell 100.

[0049] The case 200 may house a plurality of battery cells 100 and a cooling device 300 therein and form the exterior of the secondary battery module 10. For example, as shown in Fig. 1, the case 200 may be configured to have an internal storage space, and to have a main body frame 210 with open ends on both sides coupled to end frames 220 that cover the open ends of the main body frame 210.

[0050] For example, the case 200 may further include venting holes 202 formed to allow venting gas generated from a battery cell 100 to be smoothly discharged to the outside of the secondary battery module 10. The number, position, and shape of the venting holes 202 may be varied within the scope of design modifications easily made by those skilled in the art. For example, although FIG. 2 illustrates an embodiment in which the venting holes 202 are formed on the top of the case 200 so that the venting gas can be discharged above the secondary battery module 10, an alternative embodiment in which the venting holes 202 are formed on the side or bottom of the case 200 so that the venting gas can be discharged below or to the side of the secondary battery module 10 is also possible.

[0051] For example, when the secondary battery module 10 (or battery cell stack) is housed in the battery pack case, a space through which venting gas can flow may be provided in the area between the battery pack case and one side of the secondary battery module 10 (or battery cell stack) in the direction in which the venting hole 202 is formed.

[0052] For example, if a vent hole 202 is formed on the bottom surface of the case 200 so that venting gas can be discharged below the secondary battery module 10 (or battery cell stack), a certain separation space is provided between the bottom surface of the secondary battery module 10 (or battery cell stack) and the bottom surface of the battery pack case, which can serve as a flow space for the venting gas.

[0053] Meanwhile, in the embodiment, in a structure configured to discharge vent gas below the secondary battery module 10 (or battery cell stack) as described above, the inlet and outlet of each cooling device 300 may be configured to be connected to a cooling pipe disposed at the lower end of the separated space configured to allow the vent gas to flow. For example, the cooling pipes may supply refrigerant to a refrigerant flow path inside the cooling device 300 through each inlet, and as the refrigerant flows through the refrigerant flow path, the heated refrigerant may be discharged to the outside of the cooling device 300 through each outlet.

[0054] As described above, the cooling pipe connected to the inlet and outlet of the cooling device 300 and the venting gas flow space of the secondary battery module 10 (or battery cell stack) are arranged adjacent to each other, thereby ensuring flexibility in spatial design of the battery pack.

[0055] Meanwhile, unlike those shown in Figures 1 and 2, in one embodiment, the secondary battery module 10 may be a part of a battery pack in which the case 200 is omitted and a stack (assembly) of multiple battery cells 100 and a cooling device 300 is directly mounted in the pack case.

[0056] For example, when a plurality of secondary battery modules 10 are mounted in a pack case to form one battery pack, each secondary battery module 10 may be mounted inside the pack case with the case 200 forming the exterior of the module. Alternatively, the secondary battery module 10 may be mounted directly inside the pack case in the form of a battery cell stack without being surrounded by the case 200 (or surrounded by a four-sided case that does not cover the top / bottom sides of the secondary battery module 10).

[0057] Figure 3 is a schematic perspective view illustrating the structure of a cooling device 300 according to an embodiment of the present disclosure. Figure 4 is a schematic cutaway cross-sectional view illustrating the flow of refrigerant inside the cooling device 300 according to an embodiment of the present disclosure. Figures 5a to 5d are schematic cross-sectional side views illustrating the cooling device 300 according to various embodiments of the present disclosure.

[0058] 3-5d, the cooling device 300 according to various embodiments may be formed by joining two members (e.g., a first member 310 and a second member 320) formed from different materials.

[0059] For example, the cooling device 300 may be formed by combining a first member 310 of a material with a relatively low thermal conductivity with a second member 320 of a material with a relatively high thermal conductivity.

[0060] For example, the cooling device 300 may be formed by joining a first member 310 of a non-metallic material and a second member 320 of a metallic material. As an example, the first member 310 may be formed of urethane and the second member 320 may be formed of aluminum.

[0061] The first member 310 and the second member 320 may be bonded or joined together using a chemically resistant adhesive (e.g., adhesive tape). For example, the adhesive may be applied to a portion of at least one of the first member 310 and the second member 320 corresponding to the partition wall 330 that protrudes toward the inside of the cooling device 300, thereby bonding the first member 310 and the second member 320 together. The adhesive may be made of a thermosetting material. For example, the adhesive layer 240 may be made of a material that has excellent adhesive properties, electrical insulation properties, and watertightness.

[0062] Alternatively, at least one of the first member 310 and the second member 320 may be made of a material that itself has adhesive properties. For example, the first member 310 made of a non-metallic material may be made of a thermally conductive resin. For example, the first member 310 made of a non-metallic material may include a thermally conductive adhesive substance.

[0063] For example, the thermally conductive material (or the thermally conductive adhesive material) may include at least one of silicone, urethane, or acrylic.

[0064] In yet another embodiment, either the first member 310 or the second member 320 may be made of an insulating material. For example, the first member 310 may be made of a non-metallic material (or a metallic material) with excellent insulating properties, and the second member 320 may be made of a metallic material with relatively excellent electrical and thermal conductivity.

[0065] Meanwhile, in the cooling device 300, the partition wall 330 may form a space (ie, a refrigerant flow path) inside which the refrigerant can flow.

[0066] 4, the cooling device 300 may be configured such that the refrigerant flows into the cooling device 300 through the spaces between the partition walls 330, then flows in the direction of the arrow, and then flows out to the outside. However, the shape of the partition walls of the cooling device 300 in various embodiments of the present disclosure is not limited to the structure shown in FIG. 4, etc., and various partition wall structures may be applied corresponding to various design conditions of the secondary battery module 10, such as the flow rate of the refrigerant.

[0067] For example, the partition wall 330 may be configured so that the refrigerant flowing into the cooling device 300 moves in the +Y-axis direction in Fig. 4, then moves again in the -Y-axis direction, and then repeats the movement in the +Y-axis direction again. For example, unlike the cooling device 300 shown in Fig. 4, the cooling device 300 may be configured so that the inlet and outlet are adjacent to each other, or may be configured to include multiple inlets or multiple outlets therein.

[0068] In various embodiments, at least one of the first member 310 or the second member 320 may include a flat outer wall 312, 322 that faces the battery cell 100 or the case 200, and a partition 330 (e.g., a first partition 315, a second partition 325) that protrudes from the outer wall 312, 322 toward the inside of the cooling device 300.

[0069] 5a, the first member 310 and the second member 320 may have outer walls 312, 322 and partition walls 330, 315, 325, respectively, and an inner space formed when the first partition wall 315 of the first member 310 and the second partition wall 325 of the second member 320 are joined may serve as a flow path for the coolant. In this regard, according to one embodiment, the first member 310 and the second member 320 may be made of materials with different thermal conductivities, but may have substantially symmetrical shapes.

[0070] 5b and 5c, the cooling device 300 may include a partition 330 only in either the first member 310 or the second member 320. For example, the cooling device 300 may include a partition 330 (i.e., first partition 315) only in the first member 310 made of a material with low thermal conductivity, and the second member 320 made of a material with high thermal conductivity may not include a separate partition other than the outer wall 322. Conversely, the cooling device 300 may include a partition 330 (i.e., second partition 325) only in the second member 320 made of a material with high thermal conductivity, and the second member 320 made of a material with low thermal conductivity may not include a separate partition.

[0071] For example, when the first member 310 is made of a non-metallic material and the second member 320 is made of a metallic material, as shown in FIG. 5b, the partition wall 330 of the cooling device 300 is formed only by the first member 310, and the second member 320 does not include a protruding portion such as the partition wall 330. In this case, the cooling device 300 can be formed with a relatively low weight while achieving substantially the same function as that of FIG. 5a or 5c in terms of forming a refrigerant flow path, and a secondary battery module 10 with improved energy density can also be provided.

[0072] Meanwhile, in an embodiment, as shown in FIG. 5d, the cooling device 300 may be configured such that either the first member 310 or the second member 320 is configured only with an outer wall (e.g., 312, 322), and the other member includes an outer wall (e.g., 312, 322), a partition wall 330 (e.g., 315, 325), and an inner wall (e.g., 323). For example, the first member 310 may be formed of a non-metallic material (e.g., a thermally conductive resin), and the second member 320 may be formed of a metallic material. In this case, compared to the structure shown in FIGS. 5a to 5c, the contact area between the first member 310 and the second member 320 may be increased, making it easier to couple and assemble the first member 310 and the second member 320 and ensuring structural stability.

[0073] In one embodiment, if the cooling device 300 includes an inner wall (eg, 323), the thickness of the inner wall may be configured to be less than the thickness of the other outer walls.

[0074] In one embodiment, when the cooling device 300 includes an inner wall (e.g., 323), the thickness of the outer wall (e.g., 322) of the member (e.g., second member 320) that includes the inner wall may be configured to be thicker than the thickness of the outer wall (e.g., 312) of the member (e.g., first member 310) that does not include the inner wall.

[0075] For example, in a structure in which only the second member 320 has an inner wall and a partition wall, the thickness of the outer wall 322 of the second member 320 may be configured to a value corresponding to the sum of the thickness of the outer wall 312 of the first member 310 and the thickness of the inner wall 323 of the second member 320.

[0076] FIG. 6 is a schematic front view of a secondary battery module 10 according to another embodiment of the present disclosure.

[0077] Referring to FIG. 6, a secondary battery module 10 according to an embodiment may include a cooling device 300 disposed between the outermost battery cell 100 and the case 200.

[0078] The cooling devices 300 located at the outermost part of the secondary battery module 10 (i.e., the cooling devices 300 directly interposed between the battery cells 100 and the case 200) are all formed by joining a first member 310 having a relatively low thermal conductivity and a second member 320 having a relatively high thermal conductivity, but unlike the one shown in FIG. 2, in each cooling device 300, the other side (e.g., the second side) of the cooling device 300 formed by the second member 320 having a high thermal conductivity may be configured to face the adjacent battery cell 100, and one side (e.g., the first side) of the cooling device 300 formed by the first member 310 having a low thermal conductivity may be configured to face the adjacent case 200.

[0079] For example, the first member 310 may be made of a thermally conductive resin having a predetermined adhesive property, and the second member 320 may be made of a metal material having a better thermal conductivity than the thermally conductive resin. In this case, the first member 310 may also function to bond the second member 320 and the case 200 together.

[0080] Meanwhile, although not shown, in a secondary battery module 10 according to yet another embodiment, at least one cooling device 300 may include a first portion interposed between battery cells 100 and a second portion extending from the first portion. For example, the first portion may extend in a direction parallel to the Z-axis in FIG. 6, and the second portion may extend in a direction other than the Z-axis.

[0081] In the embodiment, the second portion, like the first portion, may be formed by joining a first member 310 with low thermal conductivity and a second member 320 with high thermal conductivity, and may be configured to prevent the coolant from flowing through the inner space. For example, the second portion may at least partially cover one side of the battery cell 100 (e.g., the upper side of the battery cell 100 facing the venting hole 202). For example, when venting gas is generated from one battery cell 100 due to an event such as thermal runaway, the second portion may be disposed at a position where it can guide the venting gas so that it is discharged to the venting hole 202 without being transferred to other battery cells 100.

[0082] The secondary battery module 10 according to various embodiments of the present disclosure may be widely applied in the field of green technology, such as electric vehicles, battery charging stations, and other battery-based solar and wind power generation, etc. It may also be applied to eco-friendly electric vehicles or hybrid vehicles that reduce air pollution and greenhouse gas emissions to prevent climate change.

[0083] Meanwhile, although terms indicating directions such as up and down are used in this specification, it will be obvious to those skilled in the art that such terms are used merely for the convenience of explanation and may change depending on the position of the object in question, the position of the observer, etc.

[0084] In this specification, the term "electrically connected" may refer to a state in which, when objects to be connected are connected by a connection means, an electric circuit is formed and an electric current can flow between the objects. The connection means is not particularly limited as long as an electric connection is possible, but may be a direct contact between the objects to be connected or an electric wire through which an electric current can flow.

[0085] Although various embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and it will be obvious to those skilled in the art that various modifications and variations are possible within the scope of the technical idea of ​​the present invention as set forth in the claims. In addition, some components of the above-described embodiments may be omitted, and each embodiment may be combined.

Claims

1. A plurality of battery cells; one or more cooling devices arranged in contact with at least one of the plurality of battery cells; a case that houses the plurality of battery cells and the one or more cooling devices; the one or more cooling devices a refrigerant flow path is included therein, and the refrigerant flows through the refrigerant flow path to cool at least one of the plurality of battery cells; The heat transfer device is formed by joining a first member and a second member having different thermal conductivities, the coolant flow path is formed by a space between the first member and the second member.

2. the first member is made of a non-metallic material; The battery cell stack of claim 1 , wherein the second member is made of a metallic material.

3. The battery cell stack according to claim 1 , wherein the first member is made of a thermally conductive resin.

4. The battery cell stack according to claim 1 , wherein the first member is made of at least one of silicone, urethane, and acrylic.

5. The battery cell stack according to claim 3 , wherein the first member is configured to join the second member to any one of the plurality of battery cells.

6. the one or more cooling devices are plural; Some of the plurality of cooling devices are The battery cell is interposed between two adjacent battery cells among the plurality of battery cells, Another part of the plurality of cooling devices The battery cell stack according to claim 1 , wherein the battery cell stack is interposed between a battery cell arranged at an outermost end of the plurality of battery cells and one surface of the case adjacent to the battery cell.

7. The battery cell stack according to claim 6 , wherein the second member is joined to one of the two adjacent battery cells or one surface of the case by the first member.

8. At least one of the first member and the second member is an outer wall facing one of the plurality of battery cells or the case; 2. The battery cell stack according to claim 1, further comprising: a partition wall that protrudes inward from the outer wall and forms the coolant flow path.

9. the first member and the second member each include an outer wall facing one of the plurality of battery cells or the case; one of the first member and the second member includes a partition wall that protrudes from the outer wall toward the inside and forms the refrigerant flow path; The battery cell stack of claim 1 , wherein the other of the first member or the second member does not include the partition wall.

10. The material constituting the first member has a thermal conductivity of at least less than 5 W / m K; The battery cell stack according to claim 1 , wherein the material constituting the second member has a thermal conductivity of at least 10 W / m·K or more.

11. The battery cell stack according to claim 1 , wherein the plurality of battery cells and the one or more cooling devices are alternately stacked within the case.

12. At least one of the one or more cooling devices the first member is made of a material having a thermal conductivity less than a predetermined value and faces the case; The battery cell stack according to claim 1 , wherein the second member, which is made of a material having a thermal conductivity equal to or greater than the predetermined value, faces the battery cells.

13. the material constituting the first member has a thermal conductivity less than a predetermined value; the material constituting the second member has a thermal conductivity equal to or greater than the predetermined value; At least one of the one or more cooling devices the first member contacts the first battery cell; The battery cell stack of claim 1 , wherein the second member contacts a second battery cell adjacent to the first battery cell.

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