Battery pack and motor vehicle including the same

Abstract

A battery pack and a vehicle including the same are disclosed. The battery pack according to an embodiment of the present invention includes a battery module having a plurality of battery cells arranged therein, a case for accommodating the battery module, and a bus bar unit connected to the battery module, the bus bar unit being provided to enable not only electrical connection but also heat dissipation.

Description

Technical Field

[0001] This application claims priority based on Korean Patent Application No. 10-2021-0093113, filed on July 15, 2021, and all of the contents disclosed in the specification and drawings of the application are incorporated into this application.

[0002] The present invention relates to a battery pack and an automobile including the same, and more particularly, to a battery pack capable of dissipating heat of a bus bar unit and an automobile including the same.

Background Art

[0003] The recent development of technologies for mobile devices and the increasing demand are remarkable, and along with this, the need for secondary batteries as an energy source is rapidly growing. Conventionally, nickel-cadmium batteries or hydrogen ion batteries have been used as secondary batteries, but recently, lithium secondary batteries that are almost free of memory effects compared to nickel-based batteries, are freely chargeable and dischargeable, have a very low self-discharge rate, and have a high energy density, are widely used.

[0004] This type of lithium secondary battery mainly uses a lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material, respectively. The lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate, each coated with such a positive electrode active material and a negative electrode active material, are arranged with a separator interposed therebetween, and an exterior material that encloses the electrode assembly together with an electrolytic solution, that is, a battery case.

[0005] A lithium secondary battery consists of a positive electrode, a negative electrode, a separator and an electrolyte sandwiched between them. Depending on what materials are used as the positive electrode active material and the negative electrode active material, it can be classified into a Lithium Ion Battery (LIB), a Polymer Lithium Ion Battery (PLIB), etc. Usually, the electrodes of these lithium secondary batteries can be formed by applying the positive or negative electrode active material to a current collector such as an aluminum or copper sheet, mesh, film, foil, etc. and then drying it.

[0006] The battery pack may be provided with a bus bar connected to the battery module to drive an object such as an automobile and a bus bar connected to the battery module to charge the battery module separately.

[0007] However, when the heat generation amount of the bus bar increases due to the use of high current, the cross-sectional area of the bus bar must be increased. Accordingly, there is a problem that the weight of the battery pack increases and the cost rises.

Summary of the Invention

Problems to be Solved by the Invention

[0008] Therefore, the technical problem to be solved by the present invention is to provide a battery pack and an automobile including the same in which a bus bar unit is provided so as to be heat dissipable to reduce the cross-sectional area of the bus bar, thereby achieving weight reduction and cost reduction of the battery pack.

Means for Solving the Problems

[0009] According to one aspect of the present invention, there is provided a battery pack including a battery module in which a plurality of battery cells are arranged, a case in which the battery module is accommodated, and a bus bar unit connected to the battery module, wherein the bus bar unit is provided so as to enable not only electrical connection but also heat dissipation.

[0010] Further, the bus bar unit may include a first bus bar member that connects the object and the battery module to drive the object, a second bus bar member that connects a charging member for charging the battery module and the battery module, and an insulating heat dissipation member that connects the first bus bar member and the second bus bar member, is electrically insulated, and is provided so that heat is transmitted.

[0011] Furthermore, the battery pack may further include a relay member coupled to the bus bar unit and a fastening member that fastens the bus bar unit to the relay member, wherein the first bus bar member and the second bus bar member are disposed above the relay member, and the insulating heat dissipation member may be disposed above the first bus bar member and the second bus bar member.

[0012] Furthermore, the relay member may include a first relay member coupled to the first bus bar member and a second relay member coupled to the second bus bar member, the fastening member may include a first fastening member coupled to the first bus bar member and a second fastening member coupled to the second bus bar member, and the first bus bar member and the first relay member may be fastened to a first end portion of the insulating heat dissipation member by the first fastening member, and the second bus bar member and the second relay member may be fastened to a second end portion of the insulating heat dissipation member by the second fastening member.

[0013] Furthermore, the insulating heat dissipation member may be formed in an H shape.

[0014] Furthermore, the insulating heat dissipation member may be formed of a ceramic material.

[0015] Furthermore, the fastening member may be provided as a bolt, and a rubber ring may be interposed between the bolt and the insulating heat dissipation member.

[0016] Furthermore, the fastening member may be provided as a bolt and may include a bushing member into which the bolt can be inserted.

[0017] Furthermore, the bushing member may include a main body having a hollow formed therein into which the bolt is inserted, and a protruding portion protruding from the main body toward the bolt side and contacting the bolt.

[0018] Furthermore, a plurality of notch portions in the shape of through holes may be formed in the main body between the protruding portions.

[0019] In addition to these, a buffer space may be formed between the bushing member and the bolt.

[0020] On the other hand, according to another aspect of the present invention, an automobile including the above-described battery pack may be provided.

Effects of the Invention

[0021] An embodiment of the present invention has an effect that a bus bar unit is provided so as to be heat dissipatable, thereby reducing the cross-sectional area of the bus bar, and thus reducing the weight and cost of the battery pack.

Brief Description of the Drawings

[0022]

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Best Mode for Carrying Out the Invention

[0023] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and the claims should not be construed as being limited to their ordinary or dictionary meanings. The inventor himself 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 he can appropriately define the concept of the terms in order to explain the invention in the best way. Therefore, it must 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 represent all of the technical ideas of the present invention. Therefore, there may be various equivalents and modifications that can replace them at the time of this application.

[0024] In the drawings, the size of each component or a specific part constituting the component is exaggerated, omitted, or shown schematically for ease of explanation and clarity. Therefore, the size of each component does not accurately reflect the actual size. When it is recognized that a detailed description of related known functions or configurations may obscure the gist of the present invention, the detailed description thereof is omitted.

[0025] As used in this specification, the terms "coupled" or "connected" include not only cases where one member is directly coupled or directly connected to another member, but also cases where one member is indirectly coupled or indirectly connected to another member via a joining member.

[0026] FIG. 1 is a plan view showing the interior of a battery pack according to an embodiment of the present invention, FIG. 2 is a perspective view of a bus bar unit in the battery pack according to an embodiment of the present invention, FIG. 3 is a plan view of the bus bar unit of FIG. 2, FIG. 4 is a cross-sectional view taken along the line A-A' in FIG. 3, FIG. 5 is a perspective view of the bushing member of FIG. 4, FIG. 6 is a cross-sectional view taken along the line B-B' in FIG. 5, FIG. 7 is an enlarged view of the X portion in FIG. 4, FIG. 8 is a perspective view of another embodiment of the bushing member of FIG. 5, and FIG. 9 is a cross-sectional view taken along the line C-C' in FIG. 8.

[0027] Referring to the drawings, a battery pack 10 according to an embodiment of the present invention includes a battery module 100, a case 200, and a bus bar unit 300.

[0028] Referring to FIG. 1, the battery module 100 includes a plurality of battery cells 110. The battery cells 110 may have a structure in which a plurality of unit cells arranged in the order of a positive electrode plate - separator - negative electrode plate or bi-cells arranged in the order of a positive electrode plate - separator - negative electrode plate - separator - positive electrode plate - separator - negative electrode plate are stacked according to the capacity of the battery.

[0029] And electrode leads may be provided on the battery cells 110. The electrode leads are a kind of terminal that is exposed to the outside and connected to an external device, and a conductive material may be used.

[0030] 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 with respect to the longitudinal direction of the battery cell 110, or the positive electrode lead and the negative electrode lead may be located in the same direction with respect to the longitudinal direction of the battery cell 110.

[0031] On one hand, the battery module 100 may be provided with a plurality of cartridges for accommodating the battery cells 110. Each cartridge may be manufactured by injection molding of plastic, and a plurality of cartridges formed with accommodation portions capable of accommodating the battery cells 110 may be stacked.

[0032] A connector element or a terminal element may be provided in the cartridge assembly in which a plurality of cartridges are stacked.

[0033] The connector element may include various forms of electrical connection components or connection members for connection to, for example, a battery management system (BMS) (not shown) capable of providing data regarding the voltage or temperature of the battery cell 110.

[0034] And the terminal element is a main terminal connected to the battery cell 110, includes a positive terminal and a negative terminal, and a terminal bolt is provided in the terminal element and can be electrically connected to the outside.

[0035] The case 200 houses at least one battery module 100. When a plurality of battery modules 100 are provided, the plurality of battery modules 100 may be stacked inside the case 200 or may be arranged in various ways.

[0036] The case 200 is provided to house and protect the plurality of battery modules 100. That is, the case 200 surrounds the entire battery module 100, thereby protecting the battery module 100 from external vibration and impact.

[0037] The case 200 may be formed in a shape corresponding to the shape of the battery module 100. For example, when the overall shape of the stacked battery modules 100 is provided in a hexahedron shape, the case 200 may also be provided in a hexahedron shape corresponding thereto. However, it is not limited thereto.

[0038] The case 200 can be manufactured, for example, by bending a plate made of a metal material, whereby the case 200 can be manufactured integrally. Here, when the case 200 is manufactured integrally, the joining process is simplified, and there is an effect of simplification.

[0039] Alternatively, the case 200 can be provided to be manufactured in a removable type and joined using various methods such as welding, riveting, bolting, pinning, brackets, or moment joining methods. Note that the battery pack 10 may include various devices for controlling the charging and discharging of the battery module 100, that is, a BMS, a current sensor, a fuse, and the like.

[0040] The bus bar unit 300 is connected to the battery module 100. The bus bar unit 300 is provided not only to be electrically connected to the battery module 100 but also to be capable of heat dissipation.

[0041] Referring to FIGS. 2 and 3, the bus bar unit 300 may include a first bus bar member 310, a second bus bar member 320, and an insulating heat dissipation member 330.

[0042] The first bus bar member 310 is provided to connect the object 910 (see FIG. 1) and the battery module 100 in order to drive the object 910. The first bus bar member 310 can be connected to the object 910 via the connection terminal 210. Here, the object 910 connected to the battery module 100 can be various.

[0043] For example, the object 910 can be an electric vehicle. When the object 910 is an electric vehicle, the first bus bar member 310 is configured such that the electric energy used for driving the electric vehicle can move from the battery module 100 to the electric vehicle.

[0044] However, the object 910 is not limited to an electric vehicle. For the sake of easier explanation, hereinafter, the case where the object 910 is an electric vehicle will be described.

[0045] The second bus bar member 320 is provided to connect the charging member 920 (see FIG. 1) for charging the battery module 100 and the battery module 100. The second bus bar member 320 can be connected to the charging member 920 via the charging terminal 220.

[0046] That is, when the object 910 is an electric vehicle, the electric energy for driving the electric vehicle moves from the battery module 100 to the electric vehicle via the first bus bar member 310. When the battery module 100 is charged after the driving of the electric vehicle is completed, the electric energy for charging moves from the charging member 920 to the battery module 100 via the second bus bar member 320.

[0047] The insulating heat dissipation member 330 is electrically insulated and provided so that heat can be conducted, and connects the first bus bar member 310 and the second bus bar member 320. For this purpose, the insulating heat dissipation member 330 can be formed of a ceramic material.

[0048] However, the material of the insulating heat dissipation member 330 is not limited to ceramic, and various materials having insulating and heat dissipation characteristics can be used as the material of the insulating heat dissipation member 330.

[0049] As described above, when the electric vehicle is driven, since the electric energy moves from the battery module 100 to the electric vehicle via the first bus bar member 310, heat is generated in the first bus bar member 310. In particular, in the case of an electric vehicle, since a high current is used, the amount of heat generated increases.

[0050] Here, while electrical energy is moving through the first bus bar member 310, since the second bus bar member 320 is not in use, the heat generated in the first bus bar member 310 can move to the second bus bar member 320 through the insulating heat dissipation member 330 and be released to the outside.

[0051] At this time, since the insulating heat dissipation member 330 is electrically insulated, although heat is transferred from the first bus bar member 310 to the second bus bar member 320, electricity does not move. Similarly, when heat is transferred from the second bus bar member 320 to the first bus bar member 310, electricity does not move either.

[0052] And when the electric vehicle is charged, since electrical energy moves from the charging member 920 to the battery module 100 through the second bus bar member 320, heat is generated in the second bus bar member 320.

[0053] Here, while electrical energy is moving through the second bus bar member 320, since the first bus bar member 310 is not in use, the heat generated in the second bus bar member 320 can move to the first bus bar member 310 through the insulating heat dissipation member 330 and be released to the outside.

[0054] That is, if either one of the first bus bar member 310 and the second bus bar member 320 is in use, the other one is not in use, and the heat generated from the bus bar member in use can move to the non - used bus bar member through the insulating heat dissipation member 330 and be released to the outside.

[0055] Referring to FIGS. 2 and 4, the relay member 400 can be coupled to the bus bar unit 300. The first bus bar member 310 and the second bus bar member 320 can be disposed above the relay member 400. Note that the insulating heat dissipation member 330 can be disposed above the first bus bar member 310 and the second bus bar member 320.

[0056] The relay member 400 may include a first relay member 410 coupled to the first busbar member 310 and a second relay member 420 coupled to the second busbar member 320.

[0057] The fastening member 500 fastens the busbar unit 300 to the relay member 400. Various types of fastening members 500 may be provided. For example, bolts and nuts may be provided. The nut may be coupled to the relay member 400, or the nut may be integrally formed with the relay member 400 itself.

[0058] However, the fastening member 500 is not limited to bolts and nuts, and various known structures may be included in the fastening member 500. For the sake of easy explanation, hereinafter, the case where the fastening member 500 is a nut integrally formed with a bolt and the relay member 400 will be described.

[0059] The fastening member 500 may include a first fastening member 510 coupled to the first busbar member 310 and a second fastening member 520 coupled to the second busbar member 320.

[0060] The first busbar member 310 and the first relay member 410 may be fastened to the first end 331 of the insulation and heat dissipation member 330 by the first fastening member 510. The second busbar member 320 and the second relay member 420 may be fastened to the second end 332 of the insulation and heat dissipation member 330 by the second fastening member 520.

[0061] Here, referring to FIGS. 2 and 3, the insulation and heat dissipation member 330 may be formed in an H shape. However, the shape of the insulation and heat dissipation member 330 is not limited to the H shape at all.

[0062] As described above, the insulation and heat dissipation member 330 may be formed of a ceramic material so that electrical insulation and heat transfer are performed well. However, the ceramic material may be easily damaged due to brittleness.

[0063] Here, in order to prevent damage to the insulating and heat-dissipating member 330 made of a ceramic material, a rubber ring 600 and a bushing member 700 may be provided.

[0064] Referring to FIG. 4, the rubber ring 600 is interposed between the bolt, which is the fastening member 500, and the insulating and heat-dissipating member 330. The rubber ring 600 protects the insulating and heat-dissipating member 330 from vertical impacts and vibrations.

[0065] And, the bushing member 700 is provided so that the bolt, which is the fastening member 500, is fitted therein. The bushing member 700 protects the insulating and heat-dissipating member 330 from lateral impacts and vibrations.

[0066] Referring to FIGS. 5 to 7, the bushing member 700 may be configured to include a main body 710 and a protruding portion 720.

[0067] A hollow 711 is formed in the main body 710, and the bolt is fitted into the hollow 711 of the main body 710. A plurality of notch portions 712 in the form of through holes may be formed in the main body 710 between the protruding portions 720.

[0068] The protruding portion 720 is formed on the main body 710 and protrudes from the main body 710 toward the bolt side and is contacted by the bolt as shown in FIG. 7. In this way, the protruding portion 720 is contacted by the bolt to relieve lateral impacts and vibrations.

[0069] On the other hand, referring to FIG. 7, a buffer space 800 may be formed between the bushing member 700 and the bolt, which is the fastening member 500. Here, the buffer space 800 prevents vibrations generated from the bolt from being directly transmitted to the insulating and heat-dissipating member 330 and protects the insulating and heat-dissipating member 330.

[0070] As another embodiment of FIGS. 5 and 6, referring to FIGS. 8 and 9, the protruding portion 720 is formed on the main body 710, and different from FIGS. 5 and 6, a plurality of notch portions 712 are not formed.

[0071] On the other hand, for the descriptions common to the embodiments of FIGS. 5 and 6 and the embodiments of FIGS. 8 and 9, the foregoing descriptions are incorporated by reference.

[0072] Hereinafter, based on the accompanying drawings, the operation and effects of the battery pack 10 according to an embodiment of the present invention will be described.

[0073] In the battery pack 10, a first bus bar member 310 and a second bus bar member 320 are provided to transmit electrical energy. Here, heat generated while electrical energy is transmitted through one of the bus bar members moves to the remaining other bus bar member through the insulating heat radiating member 330 and is released to the outside.

[0074] The insulating heat radiating member 330 may be formed of a brittle ceramic material, and a rubber ring 600 and a bushing member 700 may be provided to prevent breakage from the vibration of the bolts.

[0075] Through such a heat radiating structure, the cross-sectional area of the bus bar can be reduced, and the effects of reducing the weight and cost of the battery pack 10 can be achieved.

[0076] On the other hand, an automobile (not shown) according to an embodiment of the present invention may include the aforementioned battery pack 10. The battery pack 10 can be used for various machines or devices that use electricity, for example, an electric vehicle, and in particular, can be disposed under the floor of an electric vehicle. Here, the electric vehicle encompasses not only an electric vehicle that is driven purely by electricity but also a hybrid vehicle that combines other energy and electrical energy.

[0077] As described above, the present invention has been described with reference to limited embodiments and drawings, but 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.

Industrial Applicability

[0078] The present invention relates to a battery pack and an automobile including the same, and is particularly applicable to industries related to secondary batteries.

Claims

1. A battery module equipped with a plurality of battery cells, a case that houses the battery module, a bus bar unit connected to the battery module, a relay member coupled to the bus bar unit, a fastening member that fastens the bus bar unit to the relay member, In a battery pack comprising: The bus bar unit is capable of not only electrical connection but also heat dissipation, The bus bar unit A first bus bar member that connects the object and the battery module to drive the object, A second bus bar member that connects a charging member for charging the battery module and the battery module, An insulating heat dissipation member that connects the first bus bar member and the second bus bar member, and electrically insulates the first bus bar member and the second bus bar member and allows heat to be conducted, Including The first bus bar member and the second bus bar member are disposed above the relay member, A battery pack in which the insulating heat dissipation member is disposed above the first bus bar member and the second bus bar member.

2. The relay member includes a first relay member coupled to the first bus bar member and a second relay member coupled to the second bus bar member, The fastening member includes a first fastening member coupled to the first bus bar member and a second fastening member coupled to the second bus bar member, The first bus bar member and the first relay member are fastened to a first end portion of the insulating heat dissipation member by the first fastening member, The battery pack according to claim 1, wherein the second bus bar member and the second relay member are fastened to a second end portion of the insulating heat dissipation member by the second fastening member.

3. The battery pack according to claim 2, wherein the insulating heat dissipation member is formed in an H shape.

4. The battery pack according to claim 1, wherein the insulating heat dissipation member is formed of a ceramic material.

5. The fastening member is provided as a bolt, The battery pack according to claim 4, wherein a rubber ring is interposed between the bolt and the insulating heat dissipation member.

6. The fastening member is provided as a bolt, The battery pack according to claim 4, including a bushing member into which the bolt can be inserted.

7. The bushing member A main body having a hollow into which the bolt is inserted; A protruding portion protruding from the main body toward the bolt side and contacting the bolt; The battery pack according to claim 6, including the above.

8. The battery pack according to claim 7, wherein a plurality of through-hole-shaped notches are formed in the main body between the protruding portions.

9. The battery pack according to claim 7, wherein a buffer space is formed between the bushing member and the bolt.

10. An automobile including the battery pack according to any one of claims 1 to 9.

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