Battery pack comprising different types of battery cells

Abstract

The present invention relates to a battery pack comprising different types of battery cells, and more particularly, to a battery pack comprising: a first battery module comprising a plurality of first battery cells; a second battery module including a plurality of second battery cells; a pack case including an accommodating portion in which the first battery module and the second battery module are accommodated together; and a battery pack battery management system (BMS) that controls an available capacity of the first battery module and an available capacity of a second battery module capable of cooling the first battery module so as to be the same or similar to each other.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2022-0133603, filed on October 17, 2022, and Korean Patent Application No. 10-2023-0103738, filed on August 8, 2023, which are hereby incorporated by reference in their entirety. Technical Field

[0004] The present invention relates to a battery pack comprising battery cells of different types. Background Art

[0005] In general, a secondary battery refers to a rechargeable battery and can be used as an energy source not only for small household appliances such as mobile phones, laptops, and cameras, but also for transportation such as vehicles. Among these secondary batteries, one of the secondary batteries regarded as a vehicle energy source is a lithium secondary battery. Lithium secondary batteries generally have high performance, high stability, etc., and are manufactured by selecting materials according to the required performance, for example, battery life, charge and discharge capacity, charge and discharge speed, temperature characteristics, stability, etc.

[0006] Specifically, as electric vehicle technology continues to improve, battery packs, as one of the three core components of electric vehicles, play an important role in the performance of electric vehicles. At present, the demand for electric vehicles is gradually increasing, and in addition, the requirements for battery energy density are gradually increasing. Research on battery packs installed in electric vehicles to increase the energy density of battery cells in order to increase the mileage of electric vehicles has been actively conducted. It is well known that when the relative density of nickel in a battery cell increases, the energy density generally increases.

[0007] However, the battery in which the relative density of nickel in the battery cell is increased has a safety problem caused by severe heat generation. Specifically, when a battery pack is manufactured using a battery module including only batteries in which the relative density of nickel is increased, heat is simultaneously generated in a plurality of battery cells as the battery cells are used. Therefore, there is a problem that the performance of the battery cell is deteriorated due to heat generation.

[0008] Therefore, technology development is needed to solve the above problems. Summary of the invention

[0009] Technical issues

[0010] The present invention aims to solve the above-mentioned problems, and the present invention can prevent the performance of the battery module from being deteriorated due to thermal runaway and heat generation by accommodating a first battery module and a second battery module including different types of battery cells in a battery pack, so that one of the first battery module and the second battery module having different heat generation per unit volume is cooled by the other battery module, and by controlling the first battery module and the second battery module so that their available capacities are maintained at the same or similar level.

[0011] Technical Solution

[0012] As one embodiment according to the present invention, the present invention provides a battery pack, comprising: a first battery module, the first battery module including a plurality of first battery cells; a second battery module, the second battery module including a plurality of second battery cells; a battery pack case, the battery pack case including a accommodating portion, the first battery module and the second battery module being accommodated together in the accommodating portion; a partition, the partition defining an inner wall of the accommodating portion; and a battery pack battery management system (BMS), the battery pack BMS controlling the available capacity of the first battery module and the available capacity of the second battery module to make them the same or similar to each other, wherein the second battery module is capable of cooling the first battery module.

[0013] In addition, a heat generation amount per unit volume of each of the first battery cells may be greater than a heat generation amount per unit volume of each of the second battery cells.

[0014] In addition, the first battery module may further include a first reference battery cell in which a first reference electrode is added to the first battery cell, and the battery pack BMS may be able to measure a first reference potential difference of the first reference battery cell and a first potential difference of the first battery cell.

[0015] In addition, the first reference battery cell may include a first working electrode corresponding to the positive electrode, a first pair of electrodes corresponding to the negative electrode, and a first reference electrode, and the battery pack BMS may be able to calculate the first reference potential difference based on the potential difference between the first reference electrode and the first working electrode and the potential difference between the first reference electrode and the first pair of electrodes.

[0016] Furthermore, the battery pack BMS may estimate the available capacity of the first battery module based on the deviation between the first reference potential difference and the first potential difference.

[0017] In addition, the first battery module may further include a second reference battery cell in which a second reference electrode is added to the second battery cell, and the battery pack BMS may be able to measure a second reference potential difference of the second reference battery cell and a second potential difference of the second battery cell.

[0018] In addition, the second reference battery cell may include a second working electrode corresponding to the positive electrode, a second pair of electrodes corresponding to the negative electrode, and a second reference electrode, and the battery pack BMS may be able to calculate the second reference potential difference based on the potential difference between the second reference electrode and the second working electrode and the potential difference between the second reference electrode and the second pair of electrodes.

[0019] Furthermore, the battery pack BMS may estimate the available capacity of the second battery module based on the deviation between the second reference potential difference and the second potential difference.

[0020] In addition, the positive electrode active material of the first battery cell may include nickel, cobalt, and manganese materials, and the positive electrode active material of the second battery cell may include lithium, phosphoric acid, and iron materials.

[0021] In addition, the positive electrode active material of the second battery cell may not contain nickel.

[0022] In addition, the first battery module and the second battery module accommodated in the accommodation part may each have surfaces that contact and face each other.

[0023] In addition, surfaces of the first battery module and the second battery module that contact each other may each be coated with a thermally conductive compound.

[0024] Furthermore, surfaces of the first battery module and the second battery module that contact each other may each contain a heat dissipation material.

[0025] Furthermore, the heat dissipation material may be ceramic or synthetic resin.

[0026] In addition, a pair of a first battery module and a second battery module may be accommodated in the accommodation portion.

[0027] Furthermore, the accommodation portion may be provided in plurality, and the partition portion may partition the plurality of accommodation portions from each other.

[0028] Furthermore, the partition may be made of a heat insulating material.

[0029] In addition, the partition may include a first partition unit disposed in parallel with a length direction of the first battery module or the second battery module; and a second partition unit disposed in a direction perpendicular to the first partition unit.

[0030] In addition, the first battery module and the second battery module disposed in different receiving parts facing each other based on the partition may be disposed to face each other.

[0031] Beneficial Effects

[0032] The present invention can prevent the performance of the battery modules from being deteriorated due to thermal runaway and heat generation by accommodating a first battery module and a second battery module including different types of battery cells in one space so that the battery modules are cooled through heat exchange therebetween, and by controlling the first battery module and the second battery module so that their available capacities are maintained at the same or similar levels. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a schematic plan view showing the structure of a battery pack according to an embodiment of the present invention.

[0034] Figure 2 are schematic plan views showing the configuration of (a) a first battery cell, (b) a first reference battery cell, (c) a second battery cell, and (d) a second reference battery cell according to an embodiment of the present invention.

[0035] Figure 3 is a block diagram showing a battery pack according to an embodiment of the present invention.

[0036] Figure 4 is a block diagram showing a battery pack BMS according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention belongs can easily implement the present invention. However, the present invention can be implemented in different forms and should not be interpreted as being limited to the embodiments set forth herein.

[0038] In order to clearly describe the present invention, parts that are irrelevant to the description or detailed description of related well-known technologies that may unnecessarily obscure the subject matter of the present invention will be excluded. Throughout the specification, the same reference numerals denote the same elements.

[0039] Furthermore, the terms or words used in the specification and claims should not be restrictively interpreted as general meanings or dictionary-based meanings, but should be interpreted as meanings and concepts consistent with the scope of the present invention on the basis of the principle that the inventor can appropriately define the concepts of the terms to best describe and explain his or her invention.

[0040] Reference Figure 1 The present invention relates to a battery pack 10 including different types of battery cells as one embodiment of the present invention, and the battery pack 10 may include a first battery module 100, a second battery module 200, a battery pack case 300, and a battery pack battery management system (BMS).

[0041] The first battery module 100 may include a plurality of first battery cells 110. The plurality of first battery cells 110 may be stacked and disposed in an inner space of the first battery module 100.

[0042] The second battery module 200 may include a plurality of second battery cells 210. The plurality of second battery cells 210 may be stacked and disposed in an inner space of the second battery module 200.

[0043] Each of the first battery cell 110 and the second battery cell 210 may be provided in various types such as a pouch type, a prismatic type, or a cylindrical type.

[0044] Reference Figure 2 (a), the first battery cell 110 may include a first electrode assembly, a first soft-pack case 113, a first positive electrode lead 111, and a first negative electrode lead 112. Each of the first positive electrode lead 111 and the first negative electrode lead 112 may have a structure protruding outward from the first soft-pack case 113, and the first positive electrode lead 111 and the first negative electrode lead 112 may protrude together from one side surface of the first soft-pack case 113, or protrude from one side surface and the other side surface, respectively.

[0045] The first electrode assembly may have a structure in which a positive electrode collector / positive electrode active material layer / separator / negative electrode active material layer / negative electrode collector are stacked in sequence. The positive electrode collector may include an area coated with a positive electrode active material layer, and a positive electrode non-coating portion area not coated with a positive electrode active material layer, and the positive electrode non-coating portion area may be used as a positive electrode terminal tab. The negative electrode collector may include an area coated with a negative electrode active material layer, and a negative electrode non-coating portion area not coated with a negative electrode active material layer, and the negative electrode non-coating portion area may be used as a negative electrode terminal tab. The separator may be disposed between the positive electrode collector and the negative electrode collector to prevent electrode current collectors with different polarities from contacting each other. The first positive electrode lead 111 may have one end coupled to the positive electrode terminal tab, and the first negative electrode lead 112 may have one end coupled to the negative electrode terminal tab.

[0046] Reference Figure 2 (c), similar to the first battery cell 110, the second battery cell 210 may include a second electrode assembly, a second pouch type case 213, a second positive electrode lead 211, and a second negative electrode lead 212. The description of the second battery cell 210 will be replaced with the description of the first battery cell 110.

[0047] The first battery cell 110 and the second battery cell 210 may be distinguished according to a positive active material coating a positive current collector.

[0048] The positive electrode active material of the first battery cell 110 may be an NCM positive electrode active material including nickel, cobalt and manganese components, or an NCMA positive electrode active material including nickel (Ni), cobalt (Co), manganese (Mg) and aluminum (Al) components. Specifically, since the nickel content of the positive electrode active material is higher, a battery cell with a higher energy density can be manufactured, and nickel may account for more than 60% of the positive electrode active material.

[0049] The positive electrode active material of the second battery cell may be an LFP positive electrode active material including lithium (Li), phosphoric acid (H3PO4) and iron (Fe) components. The positive electrode active material of the second battery cell may not include a nickel component.

[0050] The first battery cell 110 , whose positive active material includes nickel, may have a greater amount of heat per unit volume than the second battery cell 210 .

[0051] The first battery module 100 may further include a first reference battery cell 120 .

[0052] Reference Figure 2 (b), the first reference battery cell 120 may be a battery cell including more electrodes than the first battery cell 110. The first reference battery cell 120 is not limited thereto, and for example, a first reference electrode 123 may be added to the first battery cell 110.

[0053] The first reference battery cell 120 may include a first working electrode 121 corresponding to a positive electrode, a first counter electrode 122 corresponding to a negative electrode, and a first reference electrode 123 .

[0054] The first reference battery cell 120 may be a component coupled to the first battery module 100 and configured to estimate the precise value of the potential difference of the first battery cell 110. Since the first battery cell 110 has a dual-electrode structure of a negative electrode and a positive electrode, when measuring the potential difference, a potential difference error may occur due to the resistance value of an electrolyte or the like. In the first reference battery cell 120, current flows between the first working electrode 121 and the first counter electrode 122, and hardly flows through the first reference electrode 123. Therefore, the potential change of the first reference electrode 123 is small, so that the first reference electrode 123 can be used as a reference when calculating the first reference potential difference of the first reference battery cell 120. Here, the first reference potential difference can be accurately measured regardless of the current value between the first working electrode 121 and the first counter electrode 122.

[0055] The first reference potential difference can be calculated by measuring the relative potential values ​​of the first working electrode 121 and the first pair of electrodes 122 based on the first reference electrode 123. More specifically, the first reference potential difference can be calculated by adding the difference between the first working electrode 121 and the first reference electrode 123 and the difference between the first reference electrode 123 and the first pair of electrodes 122.

[0056] The second battery module 200 may further include a second reference battery cell 220. The second reference battery cell 220 may be a battery cell including more electrodes than the second battery cell 210. The second reference battery cell 220 is not limited thereto, and for example, a second reference electrode 223 may be added to the second battery cell 210.

[0057] Reference Figure 2 (d), the second reference battery cell 220 may be a component coupled to the second battery module 200 and configured to estimate the precise value of the potential difference of the second battery cell. Similar to the first reference battery cell 120, the second reference battery cell 220 may include a second working electrode 221 corresponding to the positive electrode, a second counter electrode 222 corresponding to the negative electrode, and a second reference electrode 223.

[0058] Similar to the first battery cell 110, since the second battery cell 210 has a double electrode structure of a negative electrode and a positive electrode, a potential difference error may occur due to the resistance value of the electrolyte when measuring the potential difference. In the second reference battery cell 220, the current flows between the second working electrode 221 and the second counter electrode 222, and hardly flows through the second reference electrode 223. Therefore, the potential change of the second reference electrode 223 is small, so that when calculating the second reference potential difference of the second reference battery cell 220, the second reference electrode 223 can be used as a reference. Here, the second reference potential difference can be accurately measured regardless of the current value between the second working electrode 221 and the second counter electrode 222.

[0059] The second reference potential difference can be calculated by measuring the relative potential values ​​of the second working electrode 221 and the second pair of electrodes 222 based on the second reference electrode 223. More specifically, the second reference potential difference can be calculated by adding the difference between the second working electrode 221 and the second reference electrode 223 and the difference between the second reference electrode 223 and the second pair of electrodes 222.

[0060] The pack case 300 may refer to a frame providing an appearance of the battery pack 10 .

[0061] The battery pack case 300 may include a receiving portion 310 and a partition portion 320 .

[0062] The accommodation portion 310 may provide an inner space of the battery pack case 300 with a space for accommodating the first battery module 100 and the second battery module 200 together.

[0063] The accommodation portion 310 may have an inner wall defined by the partition 320 .

[0064] In the battery pack case 300 , a plurality of receiving parts 310 may be provided. The plurality of receiving parts 310 may be partitioned from each other by partitions 320 .

[0065] The plurality of accommodation parts 310 may be arranged in a plurality of rows and columns in the battery pack case 300 .

[0066] The partition 320 may include a first partition unit 321 and a second partition unit 322 .

[0067] The first partition unit 321 may be disposed parallel to a length direction of the first battery module or the second battery module and partition adjacent receiving parts 310 from each other.

[0068] The second partition unit 322 may be disposed in a direction perpendicular to the first partition unit 321 and partition adjacent receiving parts 310 from each other.

[0069] The partition 320 may be made of a heat-insulating material. More specifically, each of the first partition unit 321 and the second partition unit 322 may be made by including a heat-insulating material. The partition 320 may be made of a heat-insulating material, thereby preventing heat from being transferred between the battery module 100 and the battery module 200 disposed in different receiving portions 310 from each other through the partition 320. This can achieve heat transfer between a pair of first battery modules 100 and a second battery module 200 accommodated in the receiving portion 310. Specifically, the second battery module 200 generates almost no heat even when charging and discharging using the second battery cell 210, thereby cooling the first battery module 100.

[0070] The pair of the first battery module 100 and the second battery module 200 accommodated in one accommodation part 310 may be disposed to each have surfaces that contact and face each other so that heat transfer actively occurs between the first battery module 100 and the second battery module 200 .

[0071] As one embodiment according to the present invention, each of the first battery module 100 and the second battery module 200 may be coated with a thermally conductive compound that improves the heat transfer effect between the surfaces in contact with each other and enables the first battery module 100 and the second battery module 200 to be in close contact with each other. For example, the thermally conductive compound may be, but is not limited to, a thermoplastic resin such as polyamide, polyphenylene sulfide (PPS), polyolefin, polyacetal, polycarbonate (PC), polyoxymethylene (POM), polystyrene (PS), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyester, liquid crystal polyester (LCP), ethylene-vinyl acetate copolymer, acrylonitrile-butadiene-styrene (ABS), polysulfone, polyimide, and fluoroplastic, a thermosetting resin such as epoxy resin, thermosetting polyimide, phenolic resin, urea resin, melamine resin, unsaturated polyester resin, diallyl phthalate resin, silicone resin, and thermosetting polyurethane resin, or a compound thereof.

[0072] As another embodiment according to the present invention, each of the surfaces of the first battery module 100 and the second battery module 200 that contact each other may be configured to contain a heat dissipation material having high thermal conductivity. For example, the heat dissipation material may be, but is not limited to, a ceramic or synthetic resin material.

[0073] As still another embodiment according to the present invention, surfaces of the first battery module 100 and the second battery module 200 contacting each other may be provided with grooves and protrusions having shapes corresponding to each other in order to increase the contact surface area.

[0074] Reference Figure 3 A battery pack battery management system (BMS) 400 may be coupled to a battery pack housing and monitor a voltage, current, temperature, available capacity, etc. of each of a first battery cell 110, a second battery cell 210, a first reference battery cell 120, and a second reference battery cell 220 included in a first battery module 100 or a second battery module 200 so as to control and manage the battery cells 110 and 210 to prevent overcharging and over-discharging thereof.

[0075] Reference Figure 4 , the battery pack BMS 400 may include a measuring part 410 , a calculating part 420 , and a controller 430 .

[0076] The measuring unit 410 may measure a first potential difference of the first battery cell 110 , a first reference potential difference of the first reference battery cell 120 , a second potential difference of the second battery cell 210 , and a second reference potential difference of the second reference battery cell 220 .

[0077] The measuring part 410 may measure a voltage of the first positive electrode lead 111 and a voltage of the first negative electrode lead 112 of the first battery cell 110 , and the calculating part 420 may calculate a voltage corresponding to a difference between the measured voltages to measure a first potential difference.

[0078] The measuring unit 410 may measure the voltage of the first working electrode 121, the voltage of the first counter electrode 122, and the voltage of the first reference electrode 123 of the first reference battery cell 120. The calculating unit 420 may calculate a voltage corresponding to the difference between the voltage of the first working electrode 121 and the voltage of the first reference electrode 123, calculate a voltage corresponding to the difference between the voltage of the first reference electrode 123 and the voltage of the first counter electrode 122, and add the calculated voltages to measure the first reference potential difference.

[0079] The calculation part 420 may calculate a deviation between the calculated first reference potential difference and the calculated first potential difference. When calculating the deviation, the calculation part 420 may calculate an estimated value of available capacity of the first battery module 100 including the plurality of first battery cells 110 by using a predetermined calculation method.

[0080] The measuring part 410 may measure the voltage of the second positive electrode lead 211 and the voltage of the second negative electrode lead 212 of the second battery cell 210 , and the calculating part 420 may calculate a voltage corresponding to a difference between the measured voltages to measure a second potential difference.

[0081] The measuring unit 410 may measure the voltage of the second working electrode 221, the voltage of the second counter electrode 222, and the voltage of the second reference electrode 223 of the second reference battery cell 220. The calculating unit 420 may calculate a voltage corresponding to the difference between the voltage of the second working electrode 221 and the voltage of the second reference electrode 223, calculate a voltage corresponding to the difference between the voltage of the second reference electrode 223 and the voltage of the second counter electrode 222, and add the calculated voltages to measure the second reference potential difference.

[0082] The calculation part 420 may calculate a deviation between the calculated second reference potential difference and the calculated second potential difference. When calculating the deviation, the calculation part 420 may calculate an estimated value of available capacity of the second battery module 200 including the plurality of second battery cells 210 by using a predetermined calculation method.

[0083] The battery pack BMS 400 may control the available capacity of the first battery module 100 and the available capacity of the second battery module 200 to be the same or similar to each other. More specifically, the controller 430 may control the calculated available capacity of the first battery module 100 and the calculated available capacity of the second battery module 200 to be the same or similar to each other. Therefore, the first battery module 100, which generates more heat than the second battery module 200, may be safely controlled to prevent thermal runaway of the first battery module 100.

[0084] The controller 430 may predict the degree of degradation, replacement time, lifespan, etc. of the battery cells based on the estimated value of the available capacity of the first battery module 100 and the estimated value of the available capacity of the second battery module 200 .

[0085] Although the present invention has been described with reference to limited embodiments and drawings, the present invention is not limited thereto and may be variously implemented by a person skilled in the art to which the present invention pertains within the technical concept of the present invention and equivalents of the appended claims.

[0086] [Explanation of Reference Numerals]

[0087] 10: Battery Pack

[0088] 100: First battery module

[0089] 110: First battery cell

[0090] 111: First positive lead

[0091] 112: First negative lead

[0092] 113: The first soft-pack shell

[0093] 120: First reference battery cell

[0094] 121: First working electrode

[0095] 122: The first pair of electrodes

[0096] 123: First reference electrode

[0097] 200: Second battery module

[0098] 210: Second battery cell

[0099] 211: Second positive lead

[0100] 212: Second negative lead

[0101] 213: Second soft-pack shell

[0102] 220: Second reference battery cell

[0103] 221: Second working electrode

[0104] 222: The second pair of electrodes

[0105] 223: Second reference electrode

[0106] 300: Battery pack housing

[0107] 310: Accommodation

[0108] 320: Divider

[0109] 321: First separation unit

[0110] 322: Second partition unit

[0111] 400: Battery pack BMS

[0112] 410: Measurement Department

[0113] 420: Computing Department

[0114] 430: Controller

Claims

1. A battery pack comprising: a first battery module, the first battery module comprising a plurality of first battery cells; a second battery module, the second battery module comprising a plurality of second battery cells; a battery pack housing, the battery pack housing comprising a receiving portion, the first battery module and the second battery module being received together in the receiving portion; as well as a battery pack battery management system, namely, a battery pack BMS, the battery pack BMS being configured to control the available capacity of the first battery module and the available capacity of the second battery module to be equal to each other, The second battery module is capable of cooling the first battery module.

2. The battery pack according to claim 1, wherein: A heat generation amount per unit volume of each of the first battery cells is greater than a heat generation amount per unit volume of each of the second battery cells.

3. The battery pack according to claim 1, wherein: The first battery module further includes a first reference battery cell in which a first reference electrode is added to the first battery cell, The battery pack BMS is configured to measure a first reference potential difference of the first reference battery cell and a first potential difference of the first battery cell.

4. The battery pack according to claim 3, wherein: The first reference battery cell includes a first working electrode corresponding to the positive electrode, a first pair of electrodes corresponding to the negative electrode, and the first reference electrode. The battery pack BMS is configured to calculate the first reference potential difference based on a potential difference between the first reference electrode and the first working electrode and a potential difference between the first reference electrode and the first pair of electrodes.

5. The battery pack according to claim 4, wherein: The battery pack BMS is configured to estimate the available capacity of the first battery module based on a deviation between the first reference potential difference and the first potential difference.

6. The battery pack according to claim 5, wherein: The first battery module further includes a second reference battery cell in which a second reference electrode is added to the second battery cell, The battery pack BMS is configured to measure a second reference potential difference of the second reference battery cell and a second potential difference of the second battery cell.

7. The battery pack according to claim 6, wherein: The second reference battery cell includes a second working electrode corresponding to the positive electrode, a second pair of electrodes corresponding to the negative electrode, and the second reference electrode. The battery pack BMS is configured to calculate the second reference potential difference based on the potential difference between the second reference electrode and the second working electrode and the potential difference between the second reference electrode and the second pair of electrodes.

8. The battery pack according to claim 7, wherein: The battery pack BMS estimates the available capacity of the second battery module based on a deviation between the second reference potential difference and the second potential difference.

9. The battery pack according to claim 1, wherein: The positive electrode active material of the first battery cell comprises nickel, cobalt and manganese materials, and The positive electrode active material of the second battery cell includes lithium, phosphoric acid and iron materials.

10. The battery pack according to claim 9, wherein: The positive electrode active material of the second battery cell does not contain nickel.

11. The battery pack according to claim 1, wherein: The first battery module and the second battery module accommodated in the accommodation part each have surfaces facing and contacting each other.

12. The battery pack according to claim 11, wherein: The surfaces of the first battery module and the second battery module that contact each other are each coated with a thermally conductive compound.

13. The battery pack according to claim 11, wherein: Surfaces of the first battery module and the second battery module that contact each other each include a heat dissipation material.

14. The battery pack according to claim 13, wherein: The heat dissipation material is ceramic or synthetic resin.

15. The battery pack according to claim 1, wherein: A pair of the first battery module and the second battery module is accommodated in the accommodation portion.

16. The battery pack according to claim 15, wherein: Also includes: a partition portion configured to define an inner wall of the receiving portion, There are a plurality of the accommodation parts, and the partitioning part separates the plurality of accommodation parts from each other.

17. The battery pack according to claim 16, wherein: The partition is made of a heat insulating material.

18. The battery pack according to claim 16, wherein: The partition comprises: a first partition unit, the first partition unit being arranged parallel to a length direction of the first battery module or the second battery module; and The second partition unit is arranged in a direction perpendicular to the first partition unit.

19. The battery pack according to claim 16, wherein: The first battery module and the second battery module disposed in different accommodation parts facing each other based on the partition are disposed to face each other.

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