Battery pack

Abstract

A battery pack according to one embodiment of the present invention may include a base plate, an outer sidewall coupled to an upper surface of the base plate, a plurality of battery cells positioned on the base plate to form an array, and an inner sidewall coupled to the upper surface of the base plate and positioned between the plurality of battery cells and the outer sidewall.

Description

[Technical Field]

[0001] The present invention relates to a battery pack.

[0002] This application claims priority based on Korean Patent Application No. 10-2023-0120713, filed on September 11, 2023, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings thereof. [Background technology]

[0003] In recent years, the demand for portable electronic products such as laptops, video cameras, and mobile phones has grown rapidly, and as the commercialization of robots and electric vehicles has progressed in earnest, research into high-performance secondary batteries that can be repeatedly charged and discharged has become active.

[0004] Currently, commercially available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium secondary batteries. Of these, lithium secondary batteries are attracting attention due to their advantages of being free to charge and discharge because they have almost no memory effect compared to nickel-based secondary batteries, a very low self-discharge rate, and a high energy density.

[0005] This type of lithium secondary battery mainly uses a lithium-based oxide and a carbon material as the positive and negative electrode active materials, respectively, and includes an electrode assembly in which a separator is sandwiched between positive and negative electrode plates coated with the positive and negative electrode active materials, and an exterior material, such as a battery case, that encloses the electrode assembly together with an electrolyte.

[0006] Generally, lithium secondary batteries can be broadly classified into can-type secondary batteries, in which the electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which the electrode assembly is housed in a pouch made of an aluminum laminate sheet, depending on the shape of the exterior material.

[0007] Recently, secondary batteries have been widely used for driving and storing energy not only in small devices such as portable electronic devices but also in medium- to large-sized devices such as electric vehicles and energy storage systems (ESS). A battery module may be configured in which a plurality of such secondary batteries are electrically connected and housed together inside a module case. A battery pack may be configured by connecting a plurality of such battery modules.

[0008] In the case of medium to large battery packs such as those used in electric vehicles, the weight can increase significantly as a result of the inclusion of numerous battery cells and battery modules to increase output and / or capacity, which necessitates a structure that can increase the rigidity of the battery pack while also increasing its energy density. Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention is directed to solving the above-mentioned problems and other problems.

[0010] Another object of the present invention may be to provide a battery pack with improved assembly efficiency.

[0011] Yet another object of the present invention may be to provide a battery pack with improved energy density. [Means for solving the problem]

[0012] To achieve the above-described object, a battery pack according to one embodiment of the present invention may include a base plate, an outer sidewall coupled to an upper surface of the base plate, a plurality of battery cells positioned on the base plate and forming an array, and an inner sidewall coupled to the upper surface of the base plate and positioned between the plurality of battery cells and the outer sidewall.

[0013] The battery pack may further include a fastening member fastening the base plate and the inner sidewall together.

[0014] Furthermore, the base plate may include a flat portion and a bent portion protruding upward from the flat portion, and the inner sidewall may be coupled to the bent portion.

[0015] Furthermore, the bend may be located on the inside of the outer sidewall.

[0016] Furthermore, the bend and inner sidewall may extend along the edge of the base plate.

[0017] Furthermore, the battery pack may further include a fastening member that passes through the bent portion and fastens the base plate and the inner sidewall together.

[0018] Furthermore, at least some of the plurality of battery cells may be secured to the inner sidewall.

[0019] Furthermore, a gap may be formed between the battery cell fixed to the inner sidewall and the flat plate portion.

[0020] Furthermore, the inner sidewall may include an outwardly protruding guide, which may be attached to the outer sidewall.

[0021] Furthermore, the outer sidewall may include a receiving groove formed at the upper end, and the guide may be received in the receiving groove.

[0022] In addition to these, the outer sidewall may include a pair of protrusions protruding from the upper end, and the guide may be located between the pair of protrusions.

[0023] A motor vehicle according to one aspect of the present invention includes the battery pack of the present invention. [Effects of the Invention]

[0024] According to at least one of the embodiments of the present invention, the rigidity of the battery pack is improved.

[0025] At least one of the embodiments of the present invention improves the energy density of the battery pack.

[0026] The drawings attached to this specification illustrate preferred embodiments of the present invention and serve to facilitate understanding of the contents of the invention and the technical ideas of the present invention, and therefore the present invention should not be interpreted as being limited to only the matters described in the drawings. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a perspective view of a battery pack according to an embodiment of the present invention; [Figure 2] 1 is an exploded view showing some components of a battery pack according to an embodiment of the present invention. [Figure 3] 1 is a view showing an inner sidewall of a battery pack according to an embodiment of the present invention. FIG. [Figure 4] 1A and 1B are diagrams illustrating an inner sidewall and a battery cell of a battery pack according to an embodiment of the present invention. [Figure 5] FIG. 5 is a perspective view of a cross-sectional configuration taken along the line AA' in FIG. 4. [Figure 6] 1A and 1B are diagrams illustrating an inner sidewall and a battery cell of a battery pack according to an embodiment of the present invention. [Figure 7] FIG. 2 is an exploded view illustrating some components of a cell array structure of a battery pack according to an embodiment of the present invention. [Figure 8] 1 is a perspective view showing a cell array structure of a battery pack according to an embodiment of the present invention; [Figure 9] FIG. 2 is a perspective view showing a base plate of a battery pack according to an embodiment of the present invention. [Figure 10] FIG. 2 is a bottom view of a base plate of a battery pack according to an embodiment of the present invention; [Figure 11] FIG. 2 is a perspective view showing a base plate and an outer side wall of a battery pack according to an embodiment of the present invention. [Figure 12] FIG. 2 illustrates some components of a battery pack according to one embodiment of the present invention. [Figure 13] FIG. 2 is a bottom-up perspective view of some components of a battery pack according to an embodiment of the present invention. [Figure 14] 14 is a diagram schematically illustrating a part of the cross-sectional configuration taken along the line BB' in FIG. 13. FIG. [Figure 15] FIG. 14 is a perspective view of a cross-sectional configuration taken along the cutting line CC' in FIG. [Figure 16] FIG. 14 is a perspective view of a cross-sectional configuration taken along the cutting line DD' in FIG. [Figure 17] FIG. 17 shows a modification of FIG. 16. [Figure 18] FIG. 17 shows another modification of FIG. 16. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. As a premise, the terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as having meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventor can appropriately define the concepts of terms himself in order to best describe the invention.

[0029] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely preferred embodiments of the present invention and do not represent the entire technical idea of ​​the present invention, and that there may be various equivalents and modifications that can be substituted for them at the time of this application.

[0030] Fig. 1 is a perspective view of a battery pack according to one embodiment of the present invention. Fig. 2 is an exploded view showing some components of a battery pack according to one embodiment of the present invention. Referring to Fig. 1 and Fig. 2, a battery pack according to one embodiment of the present invention may include a base plate 100, an outer sidewall 200, a plurality of battery cells 310, and an inner sidewall 330.

[0031] The base plate 100 may have a flat plate shape. The base plate 100 may have a generally rectangular shape.

[0032] The outer sidewall 200 may be fastened, bonded, secured, or attached to the top surface of the base plate 100. The outer sidewall 200 and the base plate 100 may form an interior space.

[0033] A plurality of battery cells 310 may be housed in the internal space. The plurality of battery cells 310 may be arranged to form an array. The plurality of battery cells 310 may be located on the base plate 100. In this case, the battery cells 310 may represent secondary batteries. The battery cells 310 may be secondary batteries having a cylindrical shape.

[0034] The inner sidewall 330 may be fastened, coupled, fixed, or attached to the upper surface of the base plate 100. The inner sidewall 330 may be located between the plurality of battery cells 310 and the outer sidewall 200.

[0035] According to this configuration of the present invention, the battery pack can stably accommodate a plurality of battery cells 310. The inner sidewall 330 can stably support the plurality of battery cells 310. This improves the rigidity of the battery pack.

[0036] 1 and 2 , a battery pack according to one embodiment of the present invention may include a bus bar assembly 400 and a pack cover 500. The pack cover 500 may cover the interior space of the battery pack. The pack cover 500 may have a plate shape. The pack cover 500 may have a shape similar to that of the base plate 100. The pack cover 500 may be fastened, coupled, fixed, or attached to the outer sidewall 200.

[0037] The bus bar assembly 400 may be located between the plurality of battery cells 310 and the pack cover 500. The bus bar assembly 400 may be physically connected to the upper sides of the plurality of battery cells 310. The bus bar assembly 400 may also be electrically connected to the plurality of battery cells 310.

[0038] The vent device 600 may be provided on the outer surface of the outer sidewall 200. When the pressure inside the battery pack becomes high, the vent device 600 may release gas.

[0039] Fig. 3 is a diagram illustrating an inner sidewall 330 of a battery pack according to one embodiment of the present invention. Fig. 4 is a diagram illustrating the inner sidewall 330 and a battery cell 310 of a battery pack according to one embodiment of the present invention. Fig. 5 is a perspective view of a cross-sectional configuration taken along the line A-A' in Fig. 4. Fig. 6 is a diagram illustrating the inner sidewall 330 and a battery cell 310 of a battery pack according to one embodiment of the present invention.

[0040] 3 to 6 , at least some of the battery cells 310 of a battery pack according to one embodiment of the present invention may be fixed to an inner sidewall 330. The inner sidewall 330 may extend along the X-axis direction. The inner sidewall 330 may include wall heads 332 at both ends in the X-axis direction. The wall heads 332 may include slots 337. The inner sidewall 330 may include a bottom rib 333 protruding inward. The inner sidewall 330 may also include a top rib 334 protruding inward. The top rib 334 may be located higher than the bottom rib 333. The battery cells 310 may be fixed between the bottom rib 333 and the top rib 334. The inner sidewall 330 may include a curved portion 336 formed on its inner side. The curved portion 336 may bend along the side surface of the battery cell 310. The curved portion 336 may support the side surface of the battery cell 310. The inner sidewall 330 may include a plurality of inwardly protruding partitions 335. Each partition 335 may protrude between the plurality of battery cells 310.

[0041] According to this configuration of the present invention, the plurality of battery cells 310 can be stably fixed and supported by the inner sidewall 330. This improves the rigidity of the battery pack.

[0042] Fig. 7 is an exploded view showing some components of a cell array structure 300 of a battery pack according to one embodiment of the present invention. Fig. 8 is a perspective view showing the cell array structure 300 of a battery pack according to one embodiment of the present invention. Referring to Figs. 7 and 8, a battery pack according to one embodiment of the present invention may include the cell array structure 300. The cell array structure 300 may include a pair of inner sidewalls 330, a plurality of side structures 320, a plurality of cooling units 340, and a plurality of battery cells 310.

[0043] The side structure 320 may extend along the X-axis direction. The side structure 320 may fix and support a plurality of battery cells 310. A plurality of side structures 320 may be provided.

[0044] The cooling unit 340 may extend along the X-axis direction. The cooling unit 340 may be in contact with multiple battery cells 310. Multiple cooling units 340 may be provided. Cooling liquid or cooling gas may flow through the cooling units 340.

[0045] The side structures 320, the plurality of battery cells 310, and the cooling units 340 may be arranged alternately. A pair of inner sidewalls 330 may be arranged on the outermost sides of the cell array structure 300.

[0046] The cell array structure 300 may be filled with a resin. The resin may bond, fix, or attach components of the cell array structure 300 to each other. The resin may also increase the rigidity of the cell array structure 300.

[0047] FIG. 9 is a perspective view showing a base plate 100 of a battery pack according to an embodiment of the present invention. FIG. 10 is a bottom view of the base plate 100 of a battery pack according to an embodiment of the present invention. Referring to FIGS. 9 and 10 , the base plate 100 according to an embodiment of the present invention may include a flat portion 110 and a bent portion 120. The bent portion 120 may be formed by bending at least a portion of the flat portion 110. The bent portion 120 may be bent in the +Z-axis direction. The bent portion 120 may extend along the X-axis direction. The bent portions 120 may be formed in pairs.

[0048] According to this configuration of the present invention, the bent portion 120 can improve the rigidity of the base plate 100.

[0049] Fig. 11 is a perspective view showing the base plate 100 and the outer sidewall 200 of a battery pack according to one embodiment of the present invention. Fig. 12 is a diagram showing some components of a battery pack according to one embodiment of the present invention. With reference to Figs. 11 and 12, the bent portion 120 of the battery pack according to one embodiment of the present invention may be located inside the outer sidewall 200. The outer sidewall 200 may extend along the periphery of the base plate 100. The bent portion 120 may be located adjacent to the outer sidewall 200. Alternatively, the bent portion 120 may contact the outer sidewall 200.

[0050] The bend 120 and inner sidewall 330 may each extend along the edge of the base plate 100 .

[0051] According to this configuration of the present invention, the bent portion 120 can improve the rigidity of the base plate 100. Furthermore, the bent portion 120 can support the cell array structure 300, and can prevent the base plate 100 from loosening.

[0052] Fig. 13 is a perspective view of some components of a battery pack according to one embodiment of the present invention viewed from below. Fig. 14 is a diagram schematically illustrating a portion of a cross-sectional configuration taken along line B-B' in Fig. 13. Fig. 15 is a perspective view of a cross-sectional configuration taken along line C-C' in Fig. 13. Fig. 16 is a perspective view of a cross-sectional configuration taken along line D-D' in Fig. 13.

[0053] 12 to 16, a battery pack according to an embodiment of the present invention may further include a fastening member S that fastens the base plate 100 and the inner side wall 330 together. The fastening member S may be fastened to lower portions of the base plate 100 and the inner side wall 330. The fastening member S may penetrate the base plate 100. A plurality of fastening members S may be provided. The fastening members S may be arranged along the X-axis direction.

[0054] The cell array structure 300 may be fixed by being fastened, fixed, coupled, or attached to the base plate 100 or the outer sidewall 200. When the inner sidewall 330 is fastened to the outer sidewall 200 in the X-axis direction or the Y-axis direction, a fastening structure may be required. Also, the free space between the inner sidewall 330 and the outer sidewall 200 may become large, which may result in a decrease in the energy density of the battery pack.

[0055] In contrast, according to the configuration of the present invention, the inner sidewall 330 is fastened to the base plate 100 in the Z-axis direction, thereby narrowing the space between the inner sidewall 330 and the outer sidewall 200. This improves the energy density of the battery pack.

[0056] 12 to 16 , the inner sidewall 330 of the battery pack according to one embodiment of the present invention may be coupled to the bent portion 120, thereby allowing the cell array structure 300 to be positioned above the bent portion 120.

[0057] According to this configuration of the present invention, it is possible to form a space between the flat plate portion 110 and the cell array structure 300. This makes it easier to control the venting of the battery cells 310. Also, the battery cells 310 are easier to cool.

[0058] 12 to 16 , a battery pack according to an embodiment of the present invention may further include a fastening member S that penetrates the bent portion 120 and fastens the base plate 100 and the inner sidewall 330. At least a portion of the fastening member S may be fitted into the inner sidewall 330. At least a portion of the fastening member S may be located in a space formed by the bent portion 120. The fastening member may also penetrate the bent portion 120.

[0059] According to this configuration of the present invention, the fastening member S does not protrude outside the flat plate portion 110. This improves the ease of assembly of the battery pack. Also, the space efficiency of the battery pack is improved.

[0060] 12 to 16 , the inner sidewall 330 of the battery pack according to one embodiment of the present invention may include a guide 338 that protrudes outward. The guide 338 may be formed on the outer surface of the inner sidewall 330. The guide 338 may also protrude toward the outer sidewall 200. A plurality of guides 338 may be provided. The guides 338 may be arranged along the X-axis direction.

[0061] The guide 338 may then be attached to the outer sidewall 200. The guide 338 may contact the upper end of the outer sidewall 200. The outer sidewall 200 may also support the guide 338.

[0062] According to this configuration of the present invention, the load of the cell array structure 300 can be transmitted to the outer sidewall 200 via the guide 338. Alternatively, the outer sidewall 200 can support the cell array structure 300 by supporting the guide 338. The load of the cell array structure 300 can be distributed via the base plate 100 and the guide 338. This makes it possible to stably support the cell array structure 300.

[0063] 12 to 16 , a gap may be formed between the flat plate portion 110 and the battery cells 310 fixed to the inner sidewall 330 of a battery pack according to an embodiment of the present invention. The base plate 100 may be made of an electrically conductive metal. The inner sidewall 330 may be located on the bent portion 120 to space the battery cells 310 from the flat plate portion 110.

[0064] According to this configuration of the present invention, the battery cells 310 and the base plate 100 can be electrically insulated from each other.

[0065] Furthermore, by forming a space between the flat plate portion 110 and the cell array structure 300, it becomes easier to control the venting of the battery cells 310. Also, it becomes easier to cool the battery cells 310.

[0066] Figure 17 is a diagram showing a modification of Figure 16. Referring to Figure 17, the outer side wall 200 of the battery pack according to one embodiment of the present invention may include a receiving groove 201 formed at its upper end. The receiving groove 201 may have a stepped shape from the upper end of the side wall. A plurality of receiving grooves 201 may be provided. The receiving grooves 201 may be provided and positioned to correspond one-to-one with the guides 338. The guides 338 may be received in the receiving grooves 201.

[0067] According to this configuration of the present invention, the receiving groove 201 can stably align and align the cell array structure 300. This improves the ease of assembling the battery pack.

[0068] Fig. 18 is a diagram showing another modification of Fig. 16. Referring to Fig. 18, the outer side wall 200 of the battery pack according to one embodiment of the present invention may include a pair of protrusions 202 protruding from the upper end. The pair of protrusions 202 may be located at a regular interval in the X-axis direction. A plurality of pairs of protrusions 202 may be provided. The pair of protrusions 202 may be provided and positioned so as to correspond one-to-one with the guide 338. The guide 338 may be located between the pair of protrusions 202.

[0069] According to this configuration of the present invention, the protrusions 202 can stably position and align the cell array structure 300. This improves the ease of assembly of the battery pack.

[0070] A vehicle according to the present invention may include the battery pack according to the present invention described above. The battery pack according to the present invention may be applicable to vehicles such as electric vehicles and hybrid vehicles. In addition to the battery pack, the vehicle according to the present invention may further include a wide variety of other components included in a vehicle. For example, the vehicle according to the present invention may further include a vehicle body, a motor, a control device such as an electronic control unit (ECU), and the like.

[0071] Meanwhile, although directional terms such as up, down, left, right, front, back, inner, and outer are used in this specification, it will be obvious to those skilled in the art of the present invention that these terms are used merely for ease of explanation and may differ depending on the position of the target element, the position of the observer, etc.

[0072] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited to these in any way, and it goes without saying that a person having ordinary knowledge in the technical field to which the present invention pertains can make various changes and modifications within the technical spirit of the present invention and the equivalent scope of the appended claims.

Claims

1. A base plate and an outer sidewall coupled to an upper surface of the base plate; a plurality of battery cells positioned on the base plate and forming an array; an inner sidewall coupled to an upper surface of the base plate and positioned between the plurality of battery cells and the outer sidewall.

2. The battery pack according to claim 1 , further comprising a fastening member fastening the base plate and the inner sidewall together.

3. The base plate is A flat plate portion; a bent portion protruding upward from the flat portion, The battery pack according to claim 1 or 2, wherein the inner sidewall is connected to the bent portion.

4. The battery pack according to claim 3 , wherein the bent portion is located inside the outer sidewall.

5. The battery pack according to claim 3 , wherein the bent portion and the inner sidewall extend along an edge of the base plate.

6. The battery pack according to claim 3 , further comprising a fastening member passing through the bent portion and fastening the base plate and the inner sidewall together.

7. The battery pack according to claim 3 , wherein at least some of the plurality of battery cells are fixed to the inner sidewall.

8. The battery pack according to claim 7 , wherein a gap is formed between the flat plate portion and a battery cell fixed to the inner sidewall.

9. the inner sidewall includes an outwardly protruding guide; The battery pack according to claim 1 or 2, wherein the guide is attached to the outer sidewall.

10. The outer sidewall includes a receiving groove formed at an upper end thereof, The battery pack according to claim 9 , wherein the guide is housed in the housing groove.

11. The outer sidewall includes a pair of protrusions protruding from an upper end thereof, The battery pack according to claim 9 , wherein the guide is located between the pair of protrusions.

12. A motor vehicle comprising the battery pack according to claim 1 or 2.

Images