Battery module, battery pack, and motor vehicle including the same

Abstract

A battery module according to the present invention includes a cell assembly including at least one battery cell, a module case that houses the cell assembly, and a connector attached to the module case. The connector includes connector terminals for electrical connection with the battery cells, a connector housing that surrounds the connector terminals, a connector header body that is coupled to the connector housing and at least a portion of which is inserted into the module case and attached to the module case, and a connector gasket that is interposed between the module case and the connector header body and has a melting point of 1,000°C or higher.

Description

Technical Field

[0001] The present invention relates to a battery module, a battery pack, and an automobile including the same, and more particularly, to a battery module, a battery pack, and an automobile in which a connector is improved. This application claims priority based on Korean Patent Application No. 10-2021-0134408 filed on October 8, 2021, and all of the contents disclosed in the specification and drawings of the application are incorporated into this application.

Background Art

[0002] Secondary batteries with high applicability for each product group and having electrical characteristics such as high energy density are widely applied not only to portable devices but also to electric vehicles or hybrid vehicles driven by an electric drive source, power storage devices, and the like. Such secondary batteries are not only of primary advantage in significantly reducing the use of fossil fuels, but are also environmentally friendly in that they produce no by-products from energy use and are attracting attention as a new energy source for improving energy efficiency.

[0003] A battery pack applied to an electric vehicle or the like has a structure in which a plurality of cell assemblies each including a plurality of secondary battery cells are connected in series to obtain a high output. Also, a battery cell includes a positive electrode current collector, a negative electrode current collector, a separator, an active material, an electrolyte, etc., and repetitive charging and discharging is possible by an electrochemical reaction between the components.

[0004] On the one hand, recently, there has been an increasing need for large-capacity structures, including their use as energy storage sources, and the demand for battery packs with a multi-module structure formed by aggregating a plurality of battery modules in which a plurality of battery cells are connected in series and / or in parallel has been increasing. When configuring a battery pack, it is common to first configure a battery module consisting of at least one battery cell, and then add other components using such at least one battery module to configure the battery pack. The number of battery modules included in the battery pack, or the number of battery cells included in the battery module, can be variously set according to the required output voltage or charge / discharge capacity.

[0005] A battery module packages a battery cell and various electrical components, etc. in a module case and is provided with a connector for electrical connection to external devices, etc. outside the module case. The connector can be a connection connector for electrically connecting a plurality of battery modules to each other, a sensing connector for monitoring the voltage of the battery cell, a charging connector for connecting to a charging device for charging the battery cell, or an output connector for connecting to a motor driven using the energy charged in the battery cell, etc.

[0006] Conventionally, since battery modules are manufactured in a form in which a plurality of battery cells are densely packed in a narrow space, prevention of fires, etc. is important. In particular, when such a battery module and a battery pack including the same are applied for use in a vehicle, it is necessary to pass strict safety tests.

[0007] Connectors provided in conventional battery modules are made by general plastic injection for all parts except connector terminals, and such connectors are sealed to the module case by welding. When an abnormally high temperature occurs in a battery module to which plastic injection is applied, there is a problem that it is easily melted and cannot maintain airtightness, and the structure collapses. In particular, a battery module equipped with such a connector or a battery pack which is an aggregate of these has difficulty passing a thermal runaway test. The thermal runaway test means a test in which a GB standard, a battery pack or a system provides a thermal event alarm signal 5 minutes before a danger occurs in the passenger space of an automobile due to heat diffusion caused by thermal runaway of the battery.

[0008] Therefore, in order to satisfy the GB standard, there is a need for a connector for preventing the diffusion of a high temperature such as by a flame and / or a high pressure environment by venting gas.

Summary of the Invention

Problems to be Solved by the Invention

[0009] The problem to be solved by the present invention is to provide a battery module including an improved connector for preventing the diffusion of a high temperature such as by the generation of a flame in the battery module and / or a high pressure environment by venting gas in the battery module to the outside.

[0010] Another problem to be solved by the present invention is to provide a battery pack and an automobile with enhanced stability against fire and explosion by including such a battery module.

[0011] The technical problems to be solved by the present invention are not limited to the above problems, and other problems will be clearly understood by those skilled in the art from the following description of the invention.

Means for Solving the Problems

[0012] To solve the above problems, the battery module according to the present invention includes a cell assembly including at least one battery cell, a module case for housing the cell assembly, and a connector attached to the module case. The connector includes a connector terminal for electrical connection with the battery cell, a connector housing surrounding the connector terminal, a connector header body coupled to the connector housing and having at least a part inserted into the module case for attachment to the module case, and a connector gasket interposed between the module case and the connector header body and having a melting point of 1,000 °C or higher.

[0013] An opening is formed in the module case, and the connector header body makes airtight the opening while being in surface contact with the module case via the connector gasket inside the opening.

[0014] The connector gasket may be in a frame shape having a hollow of the same size as the opening.

[0015] The connector gasket and the connector header body may be bolted to the module case.

[0016] Desirably, the connector gasket is a silicone gasket.

[0017] The connector header body may be made of a ceramic or metal material having a melting point of 1,000 °C or higher.

[0018] The connector housing may be coupled to the connector header body by interference fit or hook fastening.

[0019] The connector housing and the connector header body may be an integrally formed single part.

[0020] Further, the present invention provides a battery pack including at least one such battery module, and a motor vehicle including at least one such battery pack.

Advantages of the Invention

[0021] According to the present invention, there is provided a battery module including a connector improved to prevent the diffusion to the outside of a high temperature due to the generation of a flame in the battery module and / or a high pressure environment due to venting gas in the battery module, that is, a high heat resistance sealing connector.

[0022] The battery module according to the present invention includes a connector including a connector gasket having a melting point of 1,000° C. or higher, and can prevent the diffusion of a flame to the outside of the battery module even when a flame is generated in the battery module and an abnormally high temperature state occurs. Further, even when venting gas is generated in the battery module and an abnormally high pressure state occurs, an explosion through the connector side can be prevented.

[0023] Thus, according to the present invention, there is provided a battery module including a high heat resistance sealing connector that maintains the airtight structure of the battery module and endures a high temperature / high pressure environment even when thermal runaway occurs.

[0024] For example, even when the adjacent temperature of the module case rises to about 600° C. (minimum 5 minutes) or higher, the battery module including the connector proposed in the present invention can endure a high temperature / high pressure (100 kPa), and thus can prevent heat transfer. Therefore, according to the present invention, it is possible to provide a battery module with improved safety, a battery pack including the same, and a motor vehicle.

[0025] The following drawings attached to the present specification illustrate desirable embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the detailed description of the invention. Therefore, the present invention should not be construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0026]

Figure 1

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DETAILED DESCRIPTION OF THE INVENTION

[0027] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in this specification and the claims should not be construed as being limited to their ordinary and dictionary meanings, and the inventors themselves must interpret them in accordance with the meaning and concept corresponding to the technical idea of the present invention in accordance with the principle that they can appropriately define the concept of the terms in order to explain the invention in the best way.

[0028] Therefore, the embodiments described in this specification and the configurations shown in the drawings are only the most desirable embodiment of the present invention and do not represent all of the technical ideas of the present invention. It must be understood that there can be various equivalents and modifications that can replace them at the time of this application. Also, for the purpose of assisting in the understanding of the invention, the attached drawings are not to actual scale, and the dimensions of some components may be shown exaggerated.

[0029] FIG. 1 is a schematic exploded perspective view of a battery module according to an embodiment of the present invention, FIG. 2 is a front view of the battery module according to an embodiment of the present invention, showing an enlarged view of the connector portion, FIG. 3 is a perspective view showing the separation of the connector portion from the battery module according to an embodiment of the present invention, FIG. 4 is a partial cross-sectional view of FIG. 1 taken along line IV-IV' of FIG. 2, FIG. 5 is a partial cross-sectional view of FIG. 1 taken along line V-V' of FIG. 2, and FIG. 6 is a perspective view of a connector gasket included in the battery module according to an embodiment of the present invention.

[0030] First, referring to FIG. 1, a battery module 10 according to an embodiment of the present invention includes a cell assembly 100, a module case 150, and a connector 200.

[0031] The cell assembly 100 includes at least one battery cell. The battery cells constituting the cell assembly 100 can be pouch-type secondary batteries, and a plurality of them can be stacked and aligned within the cell assembly 100. The plurality of battery cells can be electrically connected to each other, and each battery cell can include an electrode assembly, an exterior material for housing the electrode assembly, and an electrode lead that protrudes outside the exterior material and is electrically connected to the electrode assembly.

[0032] The electrode leads may include a positive electrode lead and a negative electrode lead. The positive electrode lead and the negative electrode lead may be arranged in opposite directions in the longitudinal direction of the battery cell, or they may be located in the same direction. The positive electrode lead and the negative electrode lead can be made of various materials. For example, the positive electrode lead can be made of an aluminum material, and the negative electrode lead can be made of a copper material.

[0033] The electrode leads can be electrically coupled to a bus bar (not shown). The battery cell can have a structure in which a plurality of unit cells arranged in the order of positive electrode plate - separator - negative electrode plate, or a bicell arranged in the order of positive electrode plate - separator - negative electrode plate - separator - positive electrode plate - separator - negative electrode plate are stacked according to the capacity.

[0034] The cell assembly 100 can be configured by stacking a plurality of battery cells on top of each other. Here, the battery cells can have various structures, and the plurality of battery cells can be stacked in various ways.

[0035] The cell assembly 100 can include a plurality of cartridges (not shown) for housing each battery cell. Each cartridge (not shown) can be manufactured by injection molding of plastic, and a plurality of cartridges having a storage portion capable of housing a battery cell can be stacked. A terminal element can be provided in the cartridge assembly in which a plurality of cartridges are stacked. The terminal element includes a positive electrode terminal and a negative electrode terminal as main terminals connected to the battery cell, and the terminal element can be provided with a terminal bolt and electrically connected to the outside. On the other hand, the battery cell can have various shapes.

[0036] The module case 150 has an empty space inside. The module case 150 houses the cell assembly 100 and forms the appearance of the battery module 10. The module case 150 can be formed to correspond to the shape of the cell assembly 100 or the cartridge assembly. For example, when the cell assembly 100 or the cartridge assembly is hexahedral, the module case 150 can also be provided in a hexahedral shape corresponding thereto. Various electrical components may be included in the module case 150, and as an example, it may include an ICB (Internal Circuit Board) or a BMS (Battery Management System). The electrical components such as the ICB and the BMS can be electrically connected to the plurality of battery cells.

[0037] The module case 150 can be manufactured, for example, by bending a plate made of a metal material, or may be manufactured by plastic injection. And the module case 150 may be manufactured integrally or separately. Generally, the module case 150 is provided in a form in which at least one surface is open, and after inserting the cell assembly 100 from the open portion, it can have a structure that closes the open portion. The module case 150 can be provided in a rectangular parallelepiped shape as a whole.

[0038] The configuration of the module case 150 can be diverse. For example, the module case 150 may include a U-shaped frame that houses the cell assembly 100 and has an open upper part, and an upper plate that covers the cell assembly 100 above the U-shaped frame. The U-shaped frame has an open upper surface, front surface, and rear surface, and end plates can be located on the front and rear surfaces of the U-shaped frame to close the open front and rear surfaces, respectively.

[0039] In addition, the module case 150 may include a monoframe in the form of a square tube with both opposite sides open, and a front cover and a rear cover that close both opposite sides of the monoframe. The present invention is not limited to the structure of a specific module case 150.

[0040] The connector 200 is attached to the module case 150. The connector 200 can be attached to a portion within the module case 150 that facilitates electrical connection with the cell assembly 100 housed therein. For example, it can be attached to a portion close to the electrode leads of the battery cells included in the cell assembly 100. For example, as shown in the figure, in the module case 150 as well, it can be attached to an end plate, a front cover, or the rear cover side adjacent to the portion where the electrode leads of the battery cells are located. The connector 200 can be provided as various forms of electrical connection components or connection members for connection to, for example, a BMS that can provide data related to the voltage or temperature of the battery cells inside the battery module 10. And the connector 200 is coupled to the module case 150 to transmit data related to voltage or temperature to the outside.

[0041] Referring to FIGS. 2 to 6, the connector 200 includes a connector terminal 210, a connector housing 220, and a connector header body 230.

[0042] The connector terminal 210 is for electrically connecting to the battery cells of the cell assembly 100. The connector terminal 210 may include a conductive material such as, for example, copper (Cu).

[0043] The connector housing 220 surrounds the connector terminal 210. The connector housing 220 can have a structure that houses the connector terminal 210 and exposes one end.

[0044] The connector housing 220 is coupled to the connector header body 230. The connector housing 220 can be a separate part from the connector header body 230 manufactured by plastic injection. The connector housing 220 can be coupled to the connector header body 230 by interference fit or hook fastening.

[0045] The connector header body 230 can expose one end of the connector terminal 210 that is exposed from the connector housing 220. The connector header body 230 is at least partially inserted into and attached to the module case 150 so that the connector housing 220 is located outside the module case 150. The connector terminal 210 can pass through the connector housing 220 and the connector header body 230. A hole can be formed in the connector header body 230 so that the connector terminal 210 passes through it. The connector terminal 210 can be drawn into the interior of the module case 150 through the hole in the connector header body 230.

[0046] The connector header body 230 is coupled to the module case 150. The connector header body 230 can be coupled to the module case 150 in various ways.

[0047] The connector gasket 235 is interposed between the module case 150 and the connector header body 230 and has a melting point of 1,000 °C or higher.

[0048] Referring further to FIGS. 4 and 5, in this embodiment, an opening 152 is formed in the module case 150, and the connector header body 230 is in surface contact with the module case 150 with the connector gasket 235 interposed therebetween inside the opening 152 to airtight the opening 152. A fastening hole can be formed in the connector header body 230 so that the bolt 240 passes through it.

[0049] All parts of the module case 150 except the opening 152 can be sealed through a welding process. In such a situation, when a thermal runaway occurs in the battery module 10, the part most exposed to the flame and gas is the connector 200 part. In the present invention, by improving the connector 200, it is possible to prevent the high-temperature environment due to the flame generation in the battery module 10 and / or the high-pressure environment due to the venting gas in the battery module 10 from diffusing to the outside.

[0050] With the connector gasket 235 and the connector housing 220 coupled to the connector header body 230, after exposing the connector housing 220 through the opening 152 from the inside of the module case 150, the module case 150 and the connector header body 230 can be fastened with bolts 240. Alternatively, after arranging the connector header body 230 inside the module case 150 to be in surface contact with the module case 150 with the connector gasket 235 interposed therebetween, the bolts 240 can be fastened from the outside of the module case 150, and the connector housing 220 can be coupled to the connector header body 230 from the outside of the module case 150.

[0051] As shown in FIG. 6, the connector gasket 235 can be in a frame shape having a hollow of the same size as the opening 152. As also shown in FIGS. 4 and 5, the outer periphery of the connector gasket 235 can coincide with the outer periphery of the connector header body 230.

[0052] The connector gasket 235 and the connector header body 230 can be fastened together with bolts 240 to the module case 150. Reference numeral 237 is a fastening hole provided in the connector gasket 235 through which the bolts 240 pass.

[0053] Desirably, the connector gasket 235 is a silicone gasket. The connector gasket 235 maintains airtightness even during thermal runaway in the battery module 10 and is excellent in the effect of preventing flames and gas from being exposed to the outside of the battery module 10 through the connector 200. Since the connector 200 includes the connector gasket 235, it can also be referred to as a high heat resistance sealing connector. By including such a high heat resistance sealing connector, the battery module 10 meets the GB standard related to thermal runaway.

[0054] The opening 152 may be sized to be hidden by the fastening of the connector housing 220. The opening 152 may be larger than the connector housing 220, and a part of the connector header body 230 may be visible from the outside of the module case 150.

[0055] The connector header body 230 may be made of a ceramic or metal material having a melting point of 1,000 °C or higher. When a flame occurs inside the battery module 10, the adjacent temperature of the connector header body 230 may rise to about 600 °C (minimum 5 minutes) or higher. Therefore, the connector header body 230 must withstand high temperature / high pressure (100 kPa). If the connector header body 230 is made of a ceramic or metal material having a melting point of 1,000 °C or higher, it will not collapse even if a flame occurs inside the battery module 10.

[0056] According to the present invention, the connector header body 230 can be maintained without being damaged even in a relatively high-temperature environment. The connector header body 230 will not melt even if a flame directly touches it. The connector gasket 235 can also be maintained without being damaged even in a relatively high-temperature environment. The connector gasket 235 will not melt even if a flame directly touches it. The connector gasket 235 can prevent heat transfer to the connector housing 220 side on the opposite side of the module case 150.

[0057] In a conventional connector, the portions corresponding to the connector housing 220 and the connector header body 230 are composed only of plastic injection products, so they melt during thermal runaway and smoke and flames leak to the outside. There is no sealing component such as the connector gasket 235. In the present invention, by providing the connector 200 including the connector housing 220 and the connector header body 230 having a melting point of 1,000 °C or higher and high heat resistance, not only can the GB standards related to thermal runaway be satisfied, but also airtightness can be maintained.

[0058] According to the present invention as described above, even when thermal runaway occurs, a battery module that maintains the airtight structure of the battery module and includes a highly heat-resistant sealing connector that can withstand a high-temperature / high-pressure environment is provided.

[0059] In this embodiment, the case where the connector header body 230 and the connector housing 220 are separate parts has been described. As another example, the connector housing 220 and the connector header body 230 may be a single integrally formed part. After manufacturing a clad metal disk including a heat-resistant metal material and a lightweight metal material, the connector header body 230 can be manufactured by processing it into a desired form. After arranging the connector header body 230 and the connector terminal 210 in a mold, the connector housing 220 can be manufactured by melting plastic, injecting it into the mold, and curing it so as to be integrally formed with the connector header body 230. It can be said that this is according to the insert injection method. If the connector housing 220 is integrally manufactured with the connector header body 230, a strong binding force can be obtained between the connector housing 220 and the connector header body 230 without using a separate fastening member. Thereby, not only can the number of parts be reduced and the manufacturing cost be saved, but also the fastening operation can be omitted, so that the manufacturing time can be shortened, and a stable coupling structure can be formed.

[0060] FIG. 7 is a schematic diagram showing a battery pack according to an embodiment of the present invention, and FIG. 8 is a schematic diagram showing an automobile according to an embodiment of the present invention.

[0061] Referring to FIGS. 7 and 8, a battery pack 300 according to an embodiment of the present invention may include at least one battery module, such as the battery module 10 according to an embodiment, described above. Further, the battery pack 300 may include a pack case 310 that can accommodate at least one battery module 10. Furthermore, outside such a battery module 10, various other components, for example, components of a battery pack known at the time of filing of the present invention, such as a relay, a current sensor, etc., may be further included.

[0062] Since the battery module 10 is substantially rectangular parallelepiped-shaped, it is neatly arranged in the battery pack case 310, and each battery module 10 is connected so as to be able to secure the electric power necessary for the running of the automobile 400.

[0063] The battery pack case 310 is a container for fixing and storing the battery module 10, and is a rectangular parallelepiped-shaped box. And this battery pack case 310 can be disposed at a predetermined position within the automobile 400.

[0064] Desirably, the automobile 400 can be an electric vehicle. The battery pack 300 can be used as an electric energy source that provides driving force to the motor of the electric vehicle to drive the automobile 400. In this case, the battery pack 300 has a high nominal voltage of 100 V or more.

[0065] The battery pack 300 can be charged or discharged by an inverter driven by a motor and / or an internal combustion engine. The battery pack 300 can be charged by a regenerative charging device coupled to a brake. The battery pack 300 can be electrically connected to the motor of the automobile 400 through an inverter. Of course, the battery pack 300 can also be provided outside the automobile and in other devices, tools and equipment such as an electric power storage device (ESS) using a secondary battery.

[0066] Thus, the battery pack 300 according to an embodiment of the present invention and devices, tools and equipment including such a battery pack 300 as the automobile 400 include the above-described battery module 10, and thus have all the advantages of the above-described battery module 10. It is possible to embody a battery pack 300, and devices, tools and equipment such as an automobile 400 including such a battery pack 300.

[0067] With the various embodiments as described above, even if a flame occurs inside the battery module and the temperature becomes abnormally high, it is possible to prevent the spread of the flame to the outside of the battery module. Further, according to the present invention, even if venting gas is generated inside the battery module and the pressure becomes abnormally high, it is possible to prevent the explosion of the battery module.

[0068] For example, even when the adjacent temperature of the module case rises to about 600 °C (minimum 5 minutes) or more, the battery module including the connector proposed in the present invention can withstand high temperature / high pressure (100 kPa) and prevent heat transfer. Therefore, according to the present invention, it is possible to provide a battery module with improved safety, a battery pack including the same, and an automobile.

[0069] Although the present invention has been described with reference to the limited embodiments and drawings, the present invention is not limited thereto, and it goes without saying that various modifications and variations are possible within the equivalent scope of the technical idea and claims of the present invention by those having ordinary knowledge in the technical field to which the present invention pertains.

Explanation of Reference Numerals

[0070] 10: Battery module 100: Cell assembly 150: Module case 200: Connector 210: Connector terminal 220: Connector housing 230: Connector header body 235: Connector gasket

Claims

1. A cell assembly including at least one battery cell, A module case housing the cell assembly, A connector attached to the module case, comprising: The connector includes Connector terminals for electrical connection to the battery cell, A connector housing surrounding the connector terminals, A connector header body coupled to the connector housing and having at least a part inserted into the module case for attachment to the module case, A connector gasket interposed between the module case and the connector header body and having a melting point of 1,000 °C or higher, Comprising: An opening is formed in the module case, and the connector header body airtightly seals the opening while being in surface contact with the module case via the connector gasket inside the module case. The connector header body is made of a ceramic or metal material having a melting point of 1,000 °C or higher. The connector gasket and the connector housing are coupled to the connector header body, and the connector header body is fixed to the module case with the connector housing exposed to the outside of the module case through the opening from the inside of the module case. A battery module.

2. The battery module according to claim 1, wherein the connector gasket is in a frame shape having a hollow of the same size as the opening.

3. The battery module according to claim 1, wherein the connector gasket and the connector header body are bolted to the module case.

4. The battery module according to claim 1, wherein the connector gasket is a silicone gasket.

5. The battery module according to claim 1, wherein the connector housing is coupled to the connector header body by interference fit or hook fastening.

6. The battery module according to claim 1, wherein the connector housing and the connector header body are an integrally formed single part.

7. At least one battery module according to any one of claims 1 to 6, A battery pack including a package case for packaging the at least one battery module. **Claim 8** An automobile including at least one battery pack according to Claim 7.

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