Battery module, battery pack including same, and vehicle

Abstract

Provided is a battery module capable of improving cooling performance of a battery cell by directly cooling the battery cell. The battery module of the present invention comprises: a battery cell module assembly comprising a plurality of battery cells; a module case configured to support a lower portion and a side surface of the cell module assembly and open an upper portion of the cell module assembly; and a top cooling cover assembly coupled to the module case to cover an upper portion of the cell module assembly to form a sealing structure and to cool the battery cells from top to bottom by an insulating oil direct injection method.

Description

Technical Field

[0001] The present disclosure relates to a battery module, a battery pack including the same, and a vehicle, and more particularly to a battery module having a structure in which a cooling medium for cooling battery cells is directly applied to the battery cells by spraying, a battery pack including the same, and a vehicle. This application is based on and claims the benefit of priority from Korean Patent Application No. 10-2023-0179773 filed in the Korean Intellectual Property Office on December 12, 2023, the disclosure of which is incorporated herein by reference in its entirety. Background Art

[0002] Secondary batteries, which have high applicability based on product groups and electrical characteristics such as high energy density, are commonly used not only in portable devices but also in electric vehicles powered by power supplies. Such secondary batteries are attracting attention as energy sources to improve eco-friendliness and energy efficiency, as they have the major advantage of significantly reducing the use of fossil fuels and also have no byproducts generated by energy use.

[0003] Due to the demand for high output and large capacity, battery modules, which electrically connect multiple battery cells and dielectrics, and large battery packs incorporating these battery modules as unit modules, are being used in medium- and large-sized devices such as vehicles. In battery modules and battery packs, technology capable of effectively cooling the heat generated by the battery cells is becoming increasingly important as the required battery capacity increases. Cooling battery modules and battery packs is a key factor in improving the performance of electric vehicles.

[0004] Conventional battery modules use bottom cooling using a heat sink or side cooling using cooling tubes. These methods are water cooling methods that indirectly cool battery cells by flowing cooling water through the internal flow paths of the heat sink or cooling tubes.

[0005] In the case of a battery module utilizing an indirect water cooling method using cooling water, its cooling performance is limited because the cooling water does not directly contact the battery cells but indirectly contacts the battery cells via a module case accommodating the battery cells.

[0006] Furthermore, due to bottom- or side-cooling, the heat transfer path is long, thus limiting the ability to improve cooling performance. In particular, with bottom-cooling, heat generated by the battery cells is transferred to a heat sink on one side of the module housing for cooling, making it difficult to provide a heat transfer path to the other side of the module housing. Consequently, there are limitations, such as a wide temperature gap between one end of the battery cell and the other, or unsatisfactory overall cooling efficiency.

[0007] Furthermore, compared to battery cells positioned closer to the cooling water inlet, the cooling effect of the battery cells decreases as they move further away from the inlet. As the cooling water enters the battery module inlet, circulates, and is discharged, its temperature increases due to heat transferred from the battery cells. Therefore, the cooling effect of the battery cells decreases as the cooling water is discharged to the battery module outlet. For this reason, temperature variations between battery cells inevitably occur, depending on their location within the battery module.

[0008] If temperature deviations are not resolved, problems arise with the safety and durability of the battery module. Poor cooling efficiency can accelerate degradation of the battery cells, or failure to respond quickly when thermal runaway occurs in some battery cells can cause the thermal runaway to propagate, and in severe cases, can lead to disasters such as ignition and explosion of the battery module or battery pack including the battery module, potentially causing not only property damage but also safety issues.

[0009] Recently, a battery module has been developed that further applies potting resin to a water-cooled battery module to prevent heat propagation (TP), but in this case, weight and cost increase. In addition, there is a loss of manufacturing time.

[0010] In order to solve the problems of this indirect water cooling method, it is necessary to develop a battery module with a cooling structure, in which the coolant used for cooling can be directly introduced into the module housing and directly contact the battery cells.

[0011] In the case of a battery module with such a direct cooling structure, it is necessary to configure it so that the temperature of the battery cells does not vary depending on their position in the battery module. In addition, it is necessary to maintain airtightness so that the cooling medium does not leak outside the module housing. Summary of the Invention

[0012] Technical issues

[0013] The present disclosure aims to solve the problems of the prior art, and thus the present disclosure aims to provide a battery module capable of improving the cooling performance of battery cells by directly cooling the battery cells.

[0014] The present disclosure is also directed to providing a battery module in which temperature deviations between battery cells are reduced or eliminated according to positions of the battery cells within the battery module.

[0015] The present disclosure also provides a battery pack and a vehicle including such a battery module.

[0016] Technical Solution

[0017] The battery module disclosed in the present invention for solving the above-mentioned problems includes: a battery cell module assembly, which includes a plurality of battery cells; a module shell, which supports the bottom surface and side surfaces of the battery cell module assembly and leaves the top of the battery cell module assembly open; and a top cooling cover assembly, which is connected to the module shell and covers the top of the battery cell module assembly to form a sealed structure, and cools the battery cell by directly spraying insulating oil from the top to the bottom of the battery cell.

[0018] The module case may include: a bottom plate on a top surface of which the battery cell module assembly is seated; and a module frame that fixes the battery cell module assembly seated on the bottom plate.

[0019] The top cooling cover assembly may include a plurality of cooling tubes.

[0020] Preferably, the top cooling cover assembly may include: a top cover having a receiving space inside and being open at the bottom; and a plurality of cooling pipes assembled in the receiving space and having a bottom surface exposed to the top of the battery cell.

[0021] The battery module may include a plurality of inlet ports on one side of the top cover and a plurality of duct covers on the other side of the top cover.

[0022] An O-ring may be interposed between the inlet port and the assembly surface of the top cover.

[0023] The duct cover may be assembled by being inserted and press-fitted into the top cover.

[0024] The cooling pipe may have an open center along a length direction to allow the insulating oil to flow therein, wherein one end of the cooling pipe may be connected to the inlet port, and the other end of the cooling pipe may be assembled with the duct cover and closed.

[0025] The cooling pipes may be elongated in a length direction of the battery module along rows in which the battery cells are disposed, and may be disposed to be spaced apart in a width direction of the battery module.

[0026] A plurality of perforations for spraying the insulating oil may be formed in the cooling pipe.

[0027] The penetration holes may be formed on a bottom surface side of the cooling pipe and may be positioned in a zigzag manner along a length direction of the cooling pipe.

[0028] The battery module may further include an exhaust device capable of discharging internal air pressure of the battery module to the outside.

[0029] The exhaust arrangement may be included in the top cover.

[0030] The battery module may further include a gasket interposed between the module frame and the bottom plate.

[0031] The module frame may be inserted into an edge of the base plate, and the gasket may be located between an inner surface of the edge of the base plate and an outer surface of the module frame.

[0032] The battery module may further include an insulating sheet on the bottom plate.

[0033] An outlet port for circulation of the insulating oil may be provided in the module housing.

[0034] The battery pack of the present disclosure includes one or more battery modules of the present disclosure.

[0035] The vehicle of the present disclosure includes one or more battery modules of the present disclosure.

[0036] The battery module can receive insulating oil and hydraulic pressure from the vehicle's oil pump.

[0037] The vehicle may include a vehicle cooling system, wherein insulating oil of the vehicle cooling system may be supplied to the battery module, wherein the insulating oil may cool the battery cells in the battery module, and then be discharged from the battery module to be cooled in the vehicle cooling system, and then be supplied back to the battery module and circulated.

[0038] The vehicle according to the present disclosure may further include a pressure control valve for controlling the flow rate and hydraulic pressure of the insulating oil supplied to the battery module.

[0039] Beneficial effects

[0040] According to one aspect of the present disclosure, direct cooling of battery cells is achieved by injecting insulating oil. Compared to conventional indirect cooling methods using water, this method can improve heat transfer efficiency by directly cooling the battery cells. Therefore, direct cooling of the battery cells can improve the cooling performance of the battery cells.

[0041] According to the present disclosure, since cooling water is not circulated within the battery module, the problem of rising cooling water temperature near the battery module outlet and reduced cooling efficiency of the battery cells is eliminated. According to the present disclosure, each battery cell can be cooled uniformly regardless of its position within the battery module. Consequently, variations in heating temperature can be minimized. Consequently, cooling efficiency can be further improved by minimizing temperature variations between battery cells.

[0042] According to the present disclosure, there is no need to apply potting resin to prevent TP. Therefore, the weight and cost of the battery module are not increased, and manufacturing time is not lost.

[0043] According to the present disclosure, it is possible to use insulating oil that circulates through a vehicle cooling system of a vehicle while maintaining airtightness so that the insulating oil does not leak. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the foregoing disclosure, are used to provide a further understanding of the technical features of the present disclosure, and therefore, the present disclosure is not to be construed as being limited to the accompanying drawings.

[0045] Figure 1 is a perspective view of a battery module according to an embodiment of the present disclosure.

[0046] Figure 2 is an exploded perspective view of a battery module according to an embodiment of the present disclosure.

[0047] Figure 3 yes Figure 1 An exploded perspective view of a top cooling cover assembly included in a battery module.

[0048] Figure 4 It is a top view of the battery cell array in the battery module.

[0049] Figure 5 This is a bottom view of the cooling pipe.

[0050] Figure 6 It is along Figure 1 A cross-sectional view taken along line AA'.

[0051] Figure 7 is a view showing a method of injecting insulating oil into a battery module.

[0052] Figure 8 is a schematic diagram of a battery pack according to an embodiment of the present disclosure.

[0053] Figure 9 is a schematic diagram of a vehicle according to an embodiment of the present disclosure.

[0054] Figure 10 2 is a diagram for describing an insulating oil circulation structure in a vehicle according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0055] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Before the description, it should be understood that the terms used in the specification and the appended claims should not be interpreted as limited to the general and dictionary meanings, but should be interpreted based on the meanings and concepts corresponding to the technical aspects of the present disclosure on the basis of the principle that allows the inventor to appropriately define the terms for the best interpretation. Therefore, the embodiments described in this specification and the configurations shown in the drawings are only some of the most preferred embodiments of the present disclosure and are not intended to fully represent the technical aspects of the present disclosure. Therefore, it should be understood that various equivalents and modifications may be made thereto when filing this application.

[0056] Figure 1 is a perspective view of a battery module according to an embodiment of the present disclosure. Figure 2 is an exploded perspective view of a battery module according to an embodiment of the present disclosure.

[0057] Reference Figure 1 and Figure 2 The battery module 10 according to an embodiment of the present disclosure may be a three-dimensional structure having predetermined lengths, widths, and heights in the X-axis, Y-axis, and Z-axis directions, respectively. Furthermore, the battery module 10 includes a cell module assembly 100 , a module housing 200 , and a top cooling cover assembly 300 .

[0058] Due to the coupling of the module housing 200 and the top cooling cover assembly 300, the battery module 10 can have a generally cubic appearance. When the battery module 10 is installed in an electric vehicle such as an EV or HEV, the installation space is limited due to the highly integrated arrangement of vehicle components. Therefore, the battery module 10 is preferably formed into a cubic structure so that it can be installed in a narrow space, such as between the driver's seat and the passenger seat.

[0059] In the battery module 10, the cell module assembly 100 includes a plurality of battery cells 110. The battery cell 110 refers to a secondary battery including an electrode assembly, an electrolyte, and a pouch-shaped case accommodating the electrode assembly, and can be provided as a cylindrical secondary battery, a pouch-type secondary battery, or a square secondary battery. Hereinafter, in this embodiment, the plurality of battery cells 110 are described as being limited to Figure 2 The cylindrical secondary battery shown. These battery cells 110 may be a plurality of cylindrical batteries arranged in columns and rows and standing upright in a vertical direction. As an example, the battery cell 110 may be a 4680 type battery cell. Here, 4680 represents the form factor. The first two digits in the form factor represent the diameter of the secondary battery, and the remaining digits represent the height of the secondary battery. Compared to existing 18650 or 21700 battery cells, the 4680 battery cell has high efficiency and a large size.

[0060] The module case 200 supports the bottom surface and side surfaces of the battery cell module assembly 100 and opens the top of the battery cell module assembly 100. The module case 200 may be a single component.

[0061] As another example, the module housing 200 may include a base plate 210 and a module frame 230. The base plate 210 may cover the bottom surface of the cell module assembly 100. The base plate 210 may be provided as a generally plate-shaped body having an area on which the cell module assembly 100 may be placed. The cell module assembly 100 is placed on the top surface of the base plate 210. The base plate 210 may be made of a metal material or may be manufactured as a plastic injection molded product. For example, the base plate 210 may be made of a plastic material having both insulation and flame retardancy (e.g., polycarbonate, etc.). In the case of being made of a metal material, or in order to provide more insulation, an insulating sheet 220 may be further included on the base plate 210. For example, the insulating sheet 220 may be a polycarbonate sheet. As another example, an insulating coating may be included on the top surface of the base plate 210. The insulating coating may be formed by coating, applying, or attaching an insulating material of any one of silicone, polyamide, and rubber. According to this insulating coating configuration, the insulating coating effect can be maximized with a minimum amount of coating. In addition, an insulating coating is applied to the top surface of the bottom plate 210 , and thus insulation between the battery cells 110 and the bottom plate 210 may be enhanced.

[0062] The module frame 230 fixes the cell module assembly 100 placed on the base plate 210. In the illustrated example, the module frame 230 is composed of a plurality of rod-shaped members including cylindrical curved sections on one or both sides to conform to the outer circumferential surface shape of the battery cells 110 that may be arranged in a row, but the shape of the module frame 230 may vary and is not limited thereto.

[0063] The base plate 210 and the module frame 230 can be assembled with each other. This assembly can be done in various ways, such as assembly, bolt connection, joining, welding, etc. The module frame 230 can also be made of a metal material or manufactured as a plastic injection molded product. For example, the base plate 210 can be made of a plastic material (e.g., polycarbonate, etc.) that has both insulation and flame retardancy. In the case of being made of a metal material, or in order to provide more insulation, an insulating coating can be further included on the inner surface of the module frame 230. The insulating coating can be formed by coating, applying or attaching an insulating material of any one of silicone, polyamide and rubber. According to the insulating coating configuration, the insulating coating effect can be maximized with a minimum amount of coating. In addition, the insulating coating is applied to the inner surface of the module frame 230, and thus the insulation between the battery cell 110 and the module frame 230 can be enhanced.

[0064] The battery module 10 of the present disclosure cools the battery cells 110 by directly spraying a cooling medium. The cooling medium can be cooling water, but is preferably a liquid with insulating properties. In particular, the cooling medium is insulating oil. The battery module 10 of the present disclosure or a battery pack including the battery module can be installed in a vehicle such as an electric vehicle, and the insulating oil can be an oil similar to the vehicle's engine oil or gear oil.

[0065] The cooling water applied to existing battery modules has no insulating properties. Poor sealing and impact may cause cracks in the flow path, which may lead to the risk of short circuit, fire or explosion when the cooling water leaks into the electronic components. In addition, because the cooling water used for vehicles is a mixture of water and antifreeze, there is a limitation that it needs to be replaced regularly due to its vaporization characteristics. Insulating oil has high withstand voltage performance. According to the present disclosure, short circuits or safety issues due to leakage can be prevented by using insulating oil. Insulating oil has no evaporation characteristics and therefore can be used semi-permanently without replacement.

[0066] In the present disclosure, a cooling medium is sprayed directly onto the battery cells 110 to cool the battery cells 110. According to the present disclosure, insulating oil can be sprayed from the top to the bottom of the battery cells 110, particularly through a direct cooling method using insulating oil. The top cooling cover assembly 300 included in the battery module 10 of the present disclosure is an assembly component for directly cooling the battery cells 110 by spraying the cooling medium from the top to the bottom of the battery cells 110 in this manner.

[0067] The top cooling cover assembly 300 is coupled to the module housing 200 and covers the top of the cell module assembly 100 to form a sealed structure. In doing so, the battery cells 110 are cooled from top to bottom by directly spraying insulating oil.

[0068] Figure 3 yes Figure 1 An exploded perspective view of a top cooling cover assembly included in a battery module.

[0069] Reference Figure 3 The top cooling cover assembly 300 comprises a plurality of cooling tubes 320 as a basic unit. According to an embodiment of the present disclosure, the top cooling cover assembly 300 further comprises a top cover 310. The cooling tubes 320 and the top cover 310 can be integrally assembled. Even without the top cover 310, a structure in which the plurality of cooling tubes 320 are positioned at the top of the battery cell module assembly 100 is possible.

[0070] The top cover 310 has a receiving space inside and is open at the bottom. This structure can contribute to weight reduction of the battery module 10. It can also facilitate connection to the module housing 200.

[0071] For example, the top cover 310 may have a flat box-shaped lid including a rectangular top surface 311 and four side walls 312a to 312d extending downward from the top surface 311. Since the interior is hollow, the weight of the battery module 10 can be reduced, and the cooling pipe 320 can be configured to be installed on the side walls 312a and 312c facing each other.

[0072] The top cover 310 may be made of an insulating resin for electrical insulation. For example, the top cover 310 may be manufactured as a plastic injection molded product. This top cover 310 may have the advantages of not only ensuring insulation from the battery cells 110 but also ensuring ease of handling and requiring less manufacturing labor.

[0073] The cooling pipe 320 is assembled in the storage space, with its bottom surface exposed to the top of the battery cell 110. The cooling pipe 320 is a cooling pipe through which insulating oil flows. The cooling pipe 320 has an open center C along its length to allow the insulating oil to flow through the open center C. The cooling pipe 320 can be made of steel. Because the cooling pipe 320 must withstand hydraulic pressure, it is preferably made of rigid steel.

[0074] The cooling pipes 320 are elongated in a length direction of the battery module 10 along rows in which the battery cells 110 are arranged, and are disposed to be spaced apart in a width direction of the battery module 10 .

[0075] Meanwhile, in this embodiment, the cooling pipe 320 has a circular flat cross section, but a steel pipe having a square flat cross section may also be used.

[0076] Figure 4 It is a top view of the battery cell array in the battery module. Figure 5 This is a bottom view of the cooling pipe.

[0077] Reference Figure 4 and Figure 5 A plurality of through-holes 325 for injecting insulating oil are formed in the cooling pipe 320. The through-holes 325 are formed on the bottom surface side of the cooling pipe 320 and may be positioned in a zigzag manner along the length direction of the cooling pipe 320.

[0078] exist Figure 4 and Figure 5 The position, number, spacing, and spray angle of the perforations 325 can be adjusted so that no battery cells are left exposed to the insulating oil through the perforations 325 of the cooling tube 320 .

[0079] For example, the insulating oil spraying pattern through perforations 325 can be configured as a full cone pattern, where the insulating oil is sprayed in the angular space between two arrows drawn in one perforation 325. The full cone pattern allows spraying of an entire circular surface and allows adjustment of the spray angle. Conversely, the insulating oil spraying pattern through perforations 325 can be configured as a solid pattern, where the insulating oil is sprayed in the direction of each of the two arrows drawn in one perforation 325. The solid pattern allows straight-line spraying and can indicate a spray angle of 2 degrees or less.

[0080] Refer again Figure 3 , the battery module may include a plurality of inlet ports 330 on one side of the top cover 310 and a plurality of duct covers 340 on the other side of the top cover 310. For example, the inlet ports 330 may be located on one sidewall 312a of the top cover 310, and the duct covers 340 may be located on the other sidewall 312c of the top cover 310.

[0081] The inlet port 330 is provided on the top cover 310 and is connected to one end of the cooling pipe 320. The inlet port 330 is formed on one side of the cooling pipe 320 in the length direction. An O-ring 350 may be interposed between the inlet port 330 and the assembly surface of the top cover 310 to prevent the insulating oil from flowing back due to the high-pressure flow rate and for sealing. The O-ring 350 is a waterproof component that prevents the insulating oil from leaking out of the battery module 10. The inlet port 330 may be inserted into the cooling pipe 320. The insulating oil flowing in from the inlet port 330 may flow in the center C of the cooling pipe 320.

[0082] The duct cover 340 is used to generate / maintain pressure in the duct. This allows for uniform cooling even at locations where the battery cells 110 are relatively far from the inlet port 330. The duct cover 340 can be assembled by inserting and press-fitting it into the top cover 310.

[0083] A duct cover 340 is formed on the other side of the cooling pipe 320 in the longitudinal direction. The duct cover 340 may be a cylindrical stopper with one end open. The other end of the cooling pipe 320 can be fitted into the duct cover 340 and assembled. This seals the other end of the cooling pipe 320. In this embodiment, the cooling pipe 320 is inserted into the duct cover 340.

[0084] The assembly process is as follows. The top cover 310 is provided in a form in which the duct cover 340 is assembled by insertion and press-fitting into the top cover 310. The cooling pipe 320 is inserted from one side of the top cover 310, and one end of the cooling pipe 320 is assembled into the duct cover 340 located on the other side of the top cover 310. The assembly position of the cooling pipe 320 can be guided by the duct cover 340 already located on the top cover 310. Then, the O-ring 350 is placed between the inlet port 330 and the assembly surface of the top cover 310, and the inlet port 330 is assembled into the remaining end of the cooling pipe 320 to complete the assembly. The above assembly process can be easily performed by assembling the cooling pipe 320 into the duct cover 340 and the inlet port 330 into the cooling pipe 320.

[0085] One end of the cooling pipe 320 is connected to an inlet port 330 located on one side wall 312a of the top cover 310, and the other end of the cooling pipe 320 is assembled with a duct cover 340 located on the other side wall 312c of the top cover 310, so that the cooling pipe 320 is mounted on the side walls 312a and 312c. Insulating oil flowing into the cooling pipe 320 from one end through the inlet port 330 can flow to the other end of the cooling pipe 320, which is sealed by the duct cover 340. As the insulating oil, serving as the cooling medium, flows within the cooling pipe 320, it can be sprayed toward the battery cells 110 located below the cooling pipe 320 through the perforations 325 formed in the cooling pipe 320.

[0086] The two ends of the cooling pipe 320 can be firmly supported by being assembled with the top cover 310. The inlet port 330 and the duct cover 340 are provided, so that even if the battery module 10 moves, the cooling pipe 320 can be restricted from moving upward, downward, left, right, forward, and backward within the battery module 10, thereby preventing movement. The cooling pipe 320, which can be made of steel, is heavier than other surrounding parts, so even slight movement has a significant impact on the surrounding parts. According to the present disclosure, the two ends of the cooling pipe 320 are firmly supported by being assembled with the top cover 310, thereby providing structural integrity to the top cooling cover assembly 300 as an integral component. The cooling pipe 320 is prevented from moving within the battery module 10, which can ensure the performance of the battery module 10 and allow the battery module 10 to be used safely for a long time. In addition, the top cooling cover assembly 300 as an integral component is easy to handle during assembly because it is a single component and can be simply connected to the module housing 200 to form a sealed structure, thereby increasing assemblability and productivity.

[0087] The connection between the top cooling cover assembly 300 and the module housing 200 can be achieved through various methods, such as assembly, bolting, bonding, and welding. If necessary, waterproof components such as sealing strips can be positioned on the assembly surfaces of the top cooling cover assembly 300 and the module housing 200 for waterproof performance, and the top cooling cover assembly 300 and the module housing 200 can be assembled with each other.

[0088] Figure 6 It is along Figure 1 A cross-sectional view taken along line AA'. Figure 7 is a view showing a method of injecting insulating oil into a battery module.

[0089] Refer to it together Figure 2 、 Figure 6 and Figure 7 , the insulating oil 20 can be introduced from the outside of the battery module 10 through the inlet port 330 ( Figure 7 The insulating oil 20 flows inside the cooling tube 320 and is sprayed toward the battery cell 110 through the perforation 325. Figure 7 As shown by the arrows in . Since the injected insulating oil 20 flows from the top to the bottom of the battery cell 110, a gasket 240 may be further included for sealing the insulating oil 20 between the module frame 230 and the base plate 210. The gasket 240 is a waterproof component that prevents the insulating oil 20 from leaking out of the battery module 10. More specifically, the module frame 230 is inserted into the edge of the base plate 210, and the gasket 240 may be positioned between the inner surface of the edge of the base plate 210 and the outer surface of the module frame 230. The gasket 240 may be in the form of a strip that follows the shape of the edge of the base plate 210.

[0090] The gasket 240 may be made of a material that exerts predetermined elasticity so as to stably exert a desired sealing force by pressure applied during coupling and may be compressed or deformed in a vertical direction by pressure. The gasket 240 may be made of a rubber material, such as EPDM material.

[0091] In the case of a battery module with a direct cooling structure, it is necessary to maintain airtightness so that the cooling medium does not leak out of the module housing. According to the present disclosure, a waterproof structure can be achieved by an O-ring 350 and a gasket 240. In other words, the O-ring 350 and the gasket 240 can be inserted between the components that need to be sealed, and the waterproof performance can be implemented by pressure. The O-ring 350 and the gasket 240 can have a sufficient thickness between the components that need to be sealed. Therefore, when the components that need to be sealed are connected to each other, pressure is generated to compress the O-ring 350 and the gasket 240 inserted between the components that need to be sealed, so that the components that need to be sealed can be in complete and close contact with each other. An excellent sealing and waterproof structure can be achieved without causing defective factors and increasing costs, and the assembly and manufacturing processes will not be too complicated.

[0092] An outlet port 250 for circulating the insulating oil 20 is provided at the lower end of the battery module 10. Preferably, the outlet port 250 may be provided in the module housing 200. The insulating oil 20 sprayed toward the battery cell 110 flows from the top to the bottom of the battery cell 110 while in direct contact with the battery cell 110, performing a cooling function, and then is discharged through such an outlet port 250 ( Figure 7 OUT in the figure moves to the outside of the battery module 10.

[0093] Therefore, the present disclosure utilizes an oil-cooled direct cooling method, which has a higher cooling heat transfer efficiency than a water-cooled indirect cooling method. The battery module 10 of the present disclosure can receive insulating oil 20 and hydraulic pressure from the oil pump of the vehicle equipped with the battery module 10. The insulating oil 20 can be sprayed through the perforations 325 of the cooling tube 320 to uniformly and directly cool each battery cell 110.

[0094] The insulating oil 20 introduced into the inlet port 330 under high pressure is sprayed into the battery cells 110 through the perforations 325 of the cooling tube 320, thereby directly cooling the battery cells 110. Therefore, the sprayed insulating oil 20 directly cools the entire battery cell 110 while flowing from the top to the bottom of the battery cell 110. At the same time, because the cooling tube 320 does not contact the battery cell 110 and maintain hydraulic pressure like a conventional radiator or cooling tube, temperature deviations can be minimized by achieving uniform cooling performance among the battery cells 110, regardless of the battery cell 110's position in the battery module 10 or its distance from the inlet port 330.

[0095] Thereafter, the insulating oil 20 accumulated in the battery module 10 may be discharged and circulated through the outlet port 250. The insulating oil 20 discharged through the outlet port 250 may be re-cooled by the cooling system of the vehicle to repeat the above-described cooling method.

[0096] When using insulating oil 20 to directly cool the battery cells 110, it is preferable to ensure that there are no parts that block the insulating oil flow path, making cooling difficult. For example, gaps are preferably placed between the battery cells 110 to allow the insulating oil 20 to flow along the spaces between the battery cells 110. Furthermore, gaps may be placed between the module frame 230 and the base plate 210 to allow the insulating oil 20 to flow. Appropriate structures may be applied to the connection between the base plate 210 and the module frame 230, allowing the module frame 230 to be spaced upward from the base plate 210 by a gap. Furthermore, the gasket 240 may be provided at the corresponding structural position as described above.

[0097] At the same time, refer again Figures 1 to 3 The battery module 10 of the present disclosure may further include an exhaust device 360 ​​for maintaining the internal pressure of the battery module 10 at a constant level. The exhaust device 360 ​​may be a breather. The exhaust device 360 ​​may discharge the internal air pressure of the battery module 10 increased by the insulating oil to the outside. As a result, the internal pressure of the battery module 10 may be maintained at a constant level. The exhaust device 360 ​​may be further included in the top cover 310.

[0098] According to the present disclosure, cooled insulating oil is sprayed directly onto the battery cells 110 from above, improving cooling efficiency. Depending on the arrangement of the battery cells 110, the perforations 325 may be applied to the cooling tubes 320 in a zigzag pattern. By arranging the perforations 325 in a zigzag pattern rather than in a straight line, a maximum number of battery cells 110 can be directly cooled within a minimum volume. Furthermore, uniform cooling performance can be achieved across the battery cells 110.

[0099] Each cooling tube 320 is independently arranged along a row of battery cells 110. By independently arranging multiple cooling tubes rather than integrally, flow loss within the tubes can be minimized and pressure equalization can be achieved. The cooling tubes 320 are elongated in the length direction and positioned so as to be spaced apart from each other in the width direction.

[0100] At the same time, the insulating oil may include additives that maximize the cooling capacity. For example, microcapsules containing a phase change material (hereinafter referred to as PCM) may be mixed and used. When using insulating oil including microcapsules containing PCM, the insulating oil first absorbs energy in the case of heat generation in the battery cell 110, and when the heat generation continues, secondary energy absorption is possible due to the phase change of the PCM material. For example, if 288KJ / kg of paraffin-based PCM material is applied at a phase change temperature of 70°C: assuming that 300kJ of heat is generated per battery cell, a PCM including 1.1kg and 0.8g / cm 3The insulating oil may include a substance having a fire extinguishing function. Therefore, even if a fire occurs inside the battery module 10, the fire can be quickly extinguished by the fire extinguishing substance.

[0101] As another example, insulating oil such as 3M Novec can be used as the insulating oil. This insulating oil has excellent insulating properties, which can allow cooling by being in direct contact with the battery cells 110, and has a varying boiling point, which can allow phase change cooling to be applied.

[0102] By controlling the inflow and outflow speeds of the insulating oil, the battery module 10 can be filled with the insulating oil for immersion cooling, or can also be cooled without being filled with insulating oil.

[0103] When the battery module 10 is completely filled with insulating oil, uneven cooling of the battery due to angle issues during operation (for example, when an electric vehicle is traveling on a slope) can be prevented. According to the present disclosure, cooling can be performed while the insulating oil flows in a completely filled state within the battery module 10.

[0104] According to the present disclosure, cooling can be performed while the insulating oil flows in a state where the inside of the battery module 10 is not completely filled. In the case of using the insulating oil without complete filling, it is good to apply cooling using the phase change of the insulating oil.

[0105] According to the present disclosure, there is no need to apply a potting resin to prevent TP. Therefore, the weight and cost of the battery module 10 are not increased, and manufacturing time is not lost.

[0106] Meanwhile, the battery pack according to the embodiment of the present disclosure includes one or more battery modules 10 according to the embodiment of the present disclosure as described above. In addition, the vehicle according to the embodiment of the present disclosure includes the battery module 10 or battery pack according to the embodiment of the present disclosure as described above.

[0107] Figure 8 is a schematic diagram of a battery pack according to an embodiment of the present disclosure.

[0108] The battery pack 400 according to an embodiment of the present disclosure may include one or more battery modules 10 according to an embodiment of the present disclosure as described above. The battery pack 400 according to the present disclosure may also include components of a battery pack known at the time of filing this disclosure, such as a battery management system (BMS) for integrated control of charging and discharging of one or more battery modules 10, current sensors, fuses, etc. The BMS estimates the state of the battery cells 110 in the battery pack 400 and uses the estimated state information to manage the battery pack 400. For example, the BMS estimates and manages state information of the battery pack 400, such as the state of charge (SOC), state of health (SOH), maximum input / output power allowed, and output voltage of the battery pack 400. Furthermore, using this state information, the charging or discharging of the battery pack 400 can be controlled, and furthermore, the replacement time of the battery pack 400 can even be estimated. The BMS manages and monitors the state of the battery cells 110, such as voltage, current, and temperature, and based on this, maintains the battery pack 400 in an optimal state. That is, the BMS effectively manages the battery pack 400 of the electric vehicle to ensure that the electric vehicle can be driven stably, predicts replacement time of the battery pack 400, and detects abnormal conditions of the battery pack 400 in advance to control them so that vehicle accidents are limited.

[0109] The battery modules 10 may be neatly arranged in a substantially cubic form in the pack case 410 , and each battery module 10 is connected to ensure power required for driving the vehicle.

[0110] The battery pack case 410 is a container that houses the battery module 10 in a fixed manner and is a box in the form of a cube. Also, the battery pack case 410 may be provided at a predetermined position in the vehicle.

[0111] In addition, in the battery pack 400 according to the present disclosure, the module housing 200 described above can be used as a battery pack housing. In this case, components of the battery pack (such as the BMS, bus bars, and relays) can be included in the module housing 200. In this case, it is also called a cell-to-pack because the battery cells 110 are directly housed in the battery pack housing.

[0112] The battery pack 400 according to an embodiment of the present disclosure can be applied to various devices. Typical examples of such devices include modes of transportation such as electric bicycles, electric vehicles, hybrid vehicles, etc., but the present disclosure is not limited thereto. The battery pack 400 is suitable for use as a battery pack for electric vehicles. In addition, it can also be used as an energy source for ESS. ESS refers to an independent system that stores several hundred kWH or more of power. ESS is the core of the renewable energy industry. Since it is difficult to generate electricity from renewable energy sources such as solar and wind power at the desired time, it is important to store it and use it when necessary. The battery pack 400 according to an embodiment of the present disclosure can have an energy density and capacity suitable for use as an energy source for such an ESS.

[0113] Figure 9 is a schematic diagram of a vehicle according to an embodiment of the present disclosure.

[0114] The vehicle 500 according to an embodiment of the present disclosure may include one or more battery packs 400 according to an embodiment of the present disclosure or one or more battery modules 10 according to an embodiment of the present disclosure. The vehicle 500 according to the present disclosure may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle 500 includes four-wheeled vehicles and two-wheeled vehicles. According to an embodiment of the present disclosure, the vehicle 500 operates by receiving power from the battery pack 400 or the battery module 10.

[0115] The vehicle 500 may include various other components included in a vehicle, such as a vehicle body, a motor, and the like, in addition to the battery pack 400 or the battery module 10 according to the embodiment of the present disclosure.

[0116] The battery pack 400 or the battery module 10 can be set at a predetermined position in the vehicle 500. The battery pack 400 or the battery module 10 can be electrically connected to the motor of the vehicle 500 through an inverter. The battery pack 400 or the battery module 10 can be used as an electrical energy source to drive the vehicle 500 by providing driving force to the motor of the vehicle 500. In this case, the battery pack 400 or the battery module 10 is configured to have a high nominal voltage of 100V or higher. The battery pack 400 or the battery module 10 can be charged or discharged by the inverter according to the drive of the motor and / or the internal combustion engine. The battery pack 400 or the battery module 10 can be charged by a regenerative charging device connected to the brake.

[0117] In this manner, the battery pack 400 or the battery module 10 provided in the vehicle 500 can provide the electric energy required for various operations of the vehicle 500. In addition, since the battery pack 400 or the battery module 10 has the various effects described above, the vehicle 500 including the battery pack or the battery module can also fully have such effects.

[0118] Figure 102 is a diagram for describing an insulating oil circulation structure in a vehicle according to an embodiment of the present disclosure.

[0119] The battery module 10 or the battery pack 400 including the battery module can be cooled by utilizing the cooling insulating oil of the vehicle 500 in which it is mounted. The battery module 10 has a circulation path in which the insulating oil is discharged to the outside of the battery module 10 through the outlet port 250 and, after circulating through the vehicle cooling system 510, flows back into the battery module 10 through the inlet port 330. At this time, the insulating oil can be heat exchanged / transferred through the radiator of the vehicle cooling system 510.

[0120] In this manner, when the battery module 10 or battery pack 400 of the present disclosure is installed in a vehicle 500 and used, the insulating oil circulates through the following path: vehicle cooling system 510 → cooling of the battery cells 110 in the battery module 10 → discharge to the outside of the battery module 10 → vehicle cooling system 510.

[0121] In this way, the vehicle 500 can include a vehicle cooling system 510, wherein the insulating oil of the vehicle cooling system 510 can be supplied to the battery module 10, wherein the insulating oil can cool the battery cells 110 in the battery module 10, and then be discharged from the battery module 10 to be cooled in the vehicle cooling system 510, and then be supplied back to the battery module 10 and circulate.

[0122] During this cooling cycle, pressure control valve 520 may be applied before the insulating oil flows into inlet port 330. Pressure control valve 520 may be an electronically controlled solenoid valve. By receiving a current reflecting monitored values ​​based on the battery status and vehicle driving conditions, the flow rate and hydraulic pressure of the insulating oil flowing into battery module 10 can be controlled. The operation of pressure control valve 520 allows the insulating oil to flow in a uniform amount and can be directed to maintain a constant flow rate above a certain level.

[0123] More specifically, the vehicle 500 includes an engine control unit (ECU) 530 that controls various electrical devices of the vehicle 500. The ECU 530 can perform various controls such as braking, acceleration, steering, charging, etc. The ECU 530 can communicate with the battery module 10 or the BMS 420 of the battery pack 400 using a controller area network (CAN) communication protocol or the like.

[0124] When the BMS 420 transmits battery status information obtained by checking the voltage, current, etc. of the battery cells 110 to the ECU 530, the ECU 530 may be configured to transmit a current reflecting a monitoring value based on the battery status and the vehicle driving state to the pressure control valve 520. The pressure control valve 520 may receive the corresponding current and control the flow rate and hydraulic pressure of the insulating oil flowing into the battery module 10.

[0125] In this manner, according to the present disclosure, it is possible to use the insulating oil circulating through the vehicle cooling system 510 of the vehicle 500 while maintaining airtightness so that the insulating oil does not leak.

[0126] The present disclosure has been described above with reference to specific embodiments. However, it will be clearly understood by those skilled in the art that various modified embodiments can be implemented within the technical scope of the present disclosure. Therefore, the embodiments disclosed above should be considered from an illustrative perspective rather than a restrictive perspective. That is, the scope of the true technical concept of the present disclosure is shown in the claims, and all differences within the scope of equivalents should be interpreted as included in the present disclosure.

[0127] [Explanation of Reference Signs]

[0128] 10: Battery module 100: Cell module assembly

[0129] 110: Battery cell 200: Module housing

[0130] 210: Bottom plate 220: Insulation sheet

[0131] 230: Module frame 240: Gasket

[0132] 250: outlet port 300: top cover cooling assembly

[0133] 310: Top cover 320: Cooling pipe

[0134] 330: Inlet port 340: Pipe cover

[0135] 350: O-ring 360: Exhaust

[0136] 400: Battery pack 410: Battery pack box

[0137] 420: BMS 500: Vehicle

[0138] 510: Vehicle cooling system 520: Pressure control valve

[0139] 530: ECU

Claims

1. A battery module, comprising: A battery cell module assembly, the battery cell module assembly comprising a plurality of battery cells; a module housing that supports a bottom surface and side surfaces of the battery cell module assembly and leaves a top of the battery cell module assembly open; as well as A top cooling cover assembly is coupled to the module housing and covers a top of the battery cell module assembly to form a sealed structure, and cools the battery cell by directly spraying insulating oil from top to bottom of the battery cell.

2. The battery module according to claim 1, wherein: The module housing comprises: a base plate, the battery cell module assembly being placed on a top surface of the base plate; and A module frame is used to fix the battery cell module assembly placed on the base plate.

3. The battery module according to claim 1, wherein: The top cooling cover assembly comprises: a top cover having a storage space inside and being open at the bottom; and A plurality of cooling pipes are assembled in the receiving space and have bottom surfaces exposed to tops of the battery cells. 4 . The battery module according to claim 3 , comprising a plurality of inlet ports on one side of the top cover and a plurality of duct covers on the other side of the top cover.

5. The battery module according to claim 4, wherein: An O-ring is interposed between the inlet port and an assembly surface of the top cover.

6. The battery module according to claim 4, wherein: The duct cover is assembled by being inserted and press-fitted into the top cover.

7. The battery module according to claim 4, wherein: The cooling pipe has an open center along a length direction to allow the insulating oil to flow therein, wherein one end of the cooling pipe is connected to the inlet port, and the other end of the cooling pipe is assembled with the duct cover and closed.

8. The battery module according to claim 7, wherein: The cooling pipes extend along rows in which the battery cells are arranged in a length direction of the battery module and are arranged to be spaced apart along a width direction of the battery module.

9. The battery module according to claim 7, wherein: A plurality of perforations for spraying the insulating oil are formed in the cooling pipe.

10. The battery module according to claim 9, wherein: The penetration holes are formed on the bottom surface side of the cooling pipe and are positioned in a zigzag manner along the length direction of the cooling pipe.

11. The battery module according to claim 3, wherein: An exhaust device capable of discharging internal air pressure of the battery module to the outside is further included in the top cover. 12 . The battery module according to claim 2 , further comprising a gasket interposed between the module frame and the bottom plate.

13. The battery module according to claim 12, wherein: The module frame is inserted into the edge of the base plate, and the gasket is located between an inner surface of the edge of the base plate and an outer surface of the module frame. 14 . The battery module according to claim 2 , further comprising an insulating sheet on the bottom plate.

15. The battery module according to claim 1, wherein An outlet port for circulation of the insulating oil is provided in the module housing. 16 . A battery pack comprising one or more battery modules according to claim 1 . 17 . A vehicle comprising one or more battery modules according to claim 1 .

18. The vehicle of claim 17, wherein: The battery module receives insulating oil and hydraulic pressure from an oil pump of the vehicle.

19. The vehicle of claim 18, comprising a vehicle cooling system, in, Insulating oil of the vehicle cooling system is supplied to the battery module, wherein the insulating oil cools the battery cells in the battery module, and is then discharged from the battery module to be cooled in the vehicle cooling system, and is then supplied back to the battery module and circulated.

20. The vehicle according to claim 18, further comprising a pressure control valve for controlling a flow rate and a hydraulic pressure of insulating oil supplied to the battery module.

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