Busbar assembly, battery pack including such a busbar assembly, and vehicle including such a battery pack

Abstract

A battery pack according to an embodiment of the present invention includes a plurality of battery cells arranged along longitudinal and width directions of the battery pack, and a bus bar assembly disposed on one side of the plurality of battery cells to electrically connect the plurality of battery cells, the bus bar assembly including connection bus bars connected in series and parallel to adjacent battery cells in the longitudinal and width directions, and fusing portions formed on the connection bus bars and configured to cut off electrical connection of a battery cell in an abnormal situation in both the series and parallel directions.

Description

[Technical field]

[0001] The present invention relates to a busbar assembly, a battery pack including such a busbar assembly, and a vehicle including such a battery pack, and more particularly to a busbar assembly that can ensure safety, a battery pack including such a busbar assembly, and a vehicle including such a battery pack. This application claims priority to Korean Patent Application No. 10-2021-0032989 filed on March 12, 2021, Korean Patent Application No. 10-2021-0135352, No. 10-2021-0135353, No. 10-2021-0135354, No. 10-2021-0135355, and No. 10-2021-0135356 filed on October 12, 2021, and the contents disclosed in the specification and drawings of said applications are incorporated into this application in their entirety. [Background technology]

[0002] Secondary batteries, which have high applicability for each product group and electrical properties such as high energy density, are commonly used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are driven by electrical sources. These secondary batteries are attracting attention as a new energy source for improving energy efficiency, not only for their primary advantage of dramatically reducing the use of fossil fuels, but also for their environmental friendliness in that they do not produce any by-products from the use of energy.

[0003] Currently, secondary batteries such as lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel metal hydride batteries, and nickel zinc batteries are widely used. The operating voltage of such a unit secondary battery cell, i.e., a unit battery cell, is about 2.5V to 4.5V. Therefore, when a higher output voltage is required, a battery pack may be configured by connecting a plurality of battery cells in series. Also, a battery pack may be configured by connecting a plurality of battery cells in parallel according to a charge / discharge capacity required for the battery pack. Therefore, the number of battery cells included in the battery pack may be variously set according to a required output voltage or charge / discharge capacity.

[0004] Meanwhile, when constructing a battery pack by connecting a plurality of battery cells in series / parallel, a common method is to first construct a battery module including at least one battery cell, and then add other components to the at least one battery module to construct a battery pack or a battery rack.

[0005] A conventional battery pack includes a plurality of battery cells and a busbar assembly for electrically connecting the plurality of battery cells. Here, the conventional busbar assembly connects the plurality of battery cells in series and in parallel, guides the electrical connection between the battery cells, and includes a fusing portion for cutting off the electrical connection between the battery cells in an abnormal situation.

[0006] However, in conventional battery packs, when an abnormality occurs, the fusing unit cuts off the electrical connection between the battery cells only in one direction, either in parallel or in series, so there is a problem that the battery cell in which the abnormality occurs cannot be completely separated from the other battery cells.

[0007] As a result, in the conventional battery pack, when an abnormality occurs, the performance of all battery cells may be degraded after the electrical connection is cut off through the fusing unit. Furthermore, even after the electrical connection is cut off through the fusing unit, the battery cell in which the abnormality occurs may affect the adjacent battery cells, which may cause a serious danger to the safety of use, such as a chain reaction explosion. Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, an object of the present invention is to provide a busbar assembly capable of ensuring safety by cutting off electrical connection of a battery cell in which an abnormality has occurred in both the series and parallel directions, a battery pack including such a busbar assembly, and a vehicle including such a battery pack.

[0009] The technical problems that the present invention aims to solve are not limited to the problems mentioned above, and other problems will be clearly understood by those skilled in the art from the following description of the invention. [Means for solving the problem]

[0010] In order to achieve the above object, the present invention provides a battery pack including: a plurality of battery cells arranged along longitudinal and transverse directions of the battery pack; and a bus bar assembly disposed on one side of the plurality of battery cells and electrically connecting the plurality of battery cells, the bus bar assembly including a connection bus bar connected in series and parallel to adjacent battery cells in the longitudinal and transverse directions; and a fusing portion formed on the connection bus bar and configured to cut off electrical connection of a battery cell in which an abnormality occurs in both the series and parallel directions.

[0011] The connecting busbars may be provided in a single layer in the form of strips having a predetermined length and width.

[0012] The fusing portion may be integrally formed with the connection bus bar.

[0013] The connection busbar may include a parallel connection portion formed along one of the longitudinal direction and the width direction and configured to connect the battery cells in parallel, a series connection portion formed along the other of the longitudinal direction and the width direction and configured to connect the battery cells in series, and an interconnection portion connecting between the parallel connection portion and the series connection portion.

[0014] The fusing portion may be integrally formed with the interconnection portion.

[0015] The fusing portion may be configured to narrow a width of the interconnection portion.

[0016] The fusing portion may be recessed from the interconnection portion by a predetermined depth.

[0017] The fusing portion may be formed at each corner of an edge of the interconnection portion.

[0018] The fusing portion may be formed in the shape of a hole having a predetermined size that narrows the width of an edge of the interconnection portion.

[0019] The fusing unit may be configured to sequentially cut off electrical connection between the parallel connection unit and the series connection unit connected to the battery cell in which the abnormality occurs.

[0020] The series connection portion may include a positive electrode connecting portion that protrudes and extends a predetermined length from the interconnection portion, and a negative electrode connecting portion that is provided on the opposite side of the positive electrode connecting portion and protrudes and extends a predetermined length from the interconnection portion.

[0021] In a height direction of the bus bar assembly, a height between the positive electrode connector and the negative electrode connector may be equal to a height of a positive electrode protruding from one surface of the battery cell.

[0022] In a height direction of the bus bar assembly, a height of the interconnection part may be greater than heights of the positive electrode connecting part and the negative electrode connecting part.

[0023] The busbar assembly may include a busbar cover that covers the connection busbar.

[0024] The busbar covers may be provided in a pair, and the connecting busbar may be inserted between the pair of busbar covers.

[0025] The pair of busbar covers may include a first cover covering one side of the connection busbar, and a second cover coupled to the first cover and covering the other side of the connection busbar.

[0026] The bus bar cover may be formed with a bus bar hole having an opening space of a predetermined size for exposing the series connection portion.

[0027] The busbar hole may be formed to have an opening space larger than a size of the series connection portion.

[0028] The bus bar cover may be made of an insulating material.

[0029] The bus bar cover may include a polyimide film.

[0030] A plurality of the connection bus bars may be provided, and the bus bar cover may be provided to cover the plurality of connection bus bars.

[0031] The bus bar cover may have a guide hole for guiding an assembly position of the bus bar assembly.

[0032] The strip shape may be formed to correspond to an arrangement structure of the plurality of battery cells.

[0033] The present invention also provides a motor vehicle, comprising at least one battery pack as described above.

[0034] Furthermore, the present invention provides a busbar assembly for electrically connecting battery cells of a battery pack, the busbar assembly including: a strip-shaped connection busbar having a predetermined length and width and configured to be connected in series and in parallel to the battery cells; and a fusing portion formed on the connection busbar and configured to cut off electrical connection of a battery cell in which an abnormality occurs in both the series and parallel directions.

[0035] The connecting busbars may be provided in a single layer.

[0036] The fusing portion may be integrally formed with the connection bus bar.

[0037] The connection busbar may include a parallel connection portion formed along one of the longitudinal and width directions of the busbar assembly and configured to connect the battery cells in parallel, a series connection portion formed along the other of the longitudinal and width directions of the busbar assembly and configured to connect the battery cells in series, and an interconnection portion connecting between the parallel connection portion and the series connection portion.

[0038] The fusing portion may be integrally formed with the interconnection portion.

[0039] The fusing portion may be configured to narrow a width of the interconnection portion. Effect of the Invention

[0040] According to the present invention, it is possible to provide a bus bar assembly capable of ensuring safety by cutting off electrical connection of a battery cell in which an abnormality has occurred in both the series and parallel directions, a battery pack including such a bus bar assembly, and a vehicle including such a battery pack.

[0041] The present invention has various other effects, which will be described with reference to the embodiments, but the description of the effects that can be easily understood by those skilled in the art will be omitted.

[0042] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical ideas of the present invention. Therefore, the present invention should not be interpreted as being limited only to the matters described in the drawings. [Brief description of the drawings]

[0043] [Figure 1] 1 is a diagram illustrating a battery pack according to an embodiment of the present invention; [Diagram 2] FIG. 2 is an exploded perspective view of the battery pack of FIG. 1. [Diagram 3] 3 is a diagram for explaining a battery cell included in the battery pack shown in FIG. 2. [Figure 4] FIG. 4 is a partial cross-sectional view showing the internal structure of the battery cell of FIG. 3. [Diagram 5] FIG. 4 is a partial cross-sectional view showing an upper structure of the battery cell of FIG. 3. [Figure 6] FIG. 4 is a partial cross-sectional view showing a lower structure of the battery cell of FIG. 3. [Figure 7] FIG. 4 is a bottom view of the battery cell of FIG. 3. [Figure 8] 3 is a diagram for explaining the bus bar assembly shown in FIG. 2. [Figure 9] 9 is a diagram illustrating a coupled busbar unit of the busbar assembly shown in FIG. 8. FIG. [Figure 10]10 is a schematic exploded perspective view of the coupling busbar unit of FIG. 9. [Figure 11] 11 is an enlarged view for explaining a main part of the coupling busbar unit of FIG. 10. FIG. [Figure 12] 10 is a diagram for explaining a connection bus bar of the coupling bus bar unit of FIG. 9. FIG. [Figure 13] 13 is a plan view of a main portion of the connection bus bar of FIG. 12. [Figure 14] 14 is a diagram for explaining a fusing portion according to another embodiment of the connection bus bar of FIG. 13. FIG. [Figure 15] 14 is a diagram for explaining a fusing portion according to still another embodiment of the connection bus bar of FIG. 13. FIG. [Figure 16] 13 is a diagram for explaining the connection between the positive and negative electrodes of the battery cells through the connection bus bar of FIG. 12. FIG. [Figure 17] 13 is a diagram for explaining electrical connection between battery cells through the connection bus bars of FIG. 12. FIG. [Figure 18] 4A to 4C are diagrams illustrating an electrical connection / disconnection mechanism through a fusing portion according to an embodiment of the present invention; [Figure 19] 4A to 4C are diagrams illustrating an electrical connection / disconnection mechanism through a fusing portion according to an embodiment of the present invention; [Figure 20] 4A to 4C are diagrams illustrating an electrical connection / disconnection mechanism through a fusing portion according to an embodiment of the present invention; [Figure 21] FIG. 3 is a diagram for explaining the cooling unit shown in FIG. 2. [Figure 22] FIG. 22 is a cross-sectional view of the cooling unit of FIG. 21. [Figure 23] 3 is a diagram for explaining the side structure unit shown in FIG. 2. [Figure 24] 24 is a diagram for explaining a main plate of the side structural unit of FIG. 23. FIG. [Diagram 25] 24 is a diagram for explaining a connection structure between a battery cell and a cooling unit through the side structure unit of FIG. 23. FIG. [Figure 26]24 is a diagram for explaining a connection structure between a battery cell and a cooling unit through the side structure unit of FIG. 23. FIG. [Figure 27] 24 is a diagram for explaining the positional relationship between the battery cell and the cooling unit through the side structure unit of FIG. 23. FIG. [Figure 28] 24 is a diagram showing the bottom surface of the side structural unit when a battery cell is coupled to the side structural unit of FIG. 23. FIG. [Figure 29] 29 is an enlarged bottom view of a main portion of the side structure unit of FIG. 28. [Diagram 30] 3 is a diagram for explaining the formation of the pack case structure through injection of the filling material shown in FIG. 2. FIG. [Diagram 31] 3 is a diagram for explaining the formation of the pack case structure through injection of the filling material shown in FIG. 2. FIG. [Diagram 32] 3 is a diagram for explaining the formation of the pack case structure through injection of the filling material shown in FIG. 2. FIG. [Diagram 33] FIG. 11 is a diagram illustrating a vehicle according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0044] The present invention will be more clearly understood by describing preferred embodiments of the present invention in detail with reference to the accompanying drawings. The following embodiments are illustrative and are intended to aid in the understanding of the invention, and it should be understood that the present invention can be practiced in various modified forms from the following embodiments. In addition, the accompanying drawings may be drawn not to scale, and some components may be exaggerated in size to aid in the understanding of the invention.

[0045] FIG. 1 is a diagram for explaining a battery pack according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the battery pack of FIG.

[0046] 1 and 2, a battery pack P may be provided in an electric vehicle or a hybrid vehicle as an energy source. Hereinafter, the battery pack P provided in such an electric vehicle will be described in more detail with reference to the related drawings.

[0047] The battery pack P may include a plurality of battery cells 100 and a busbar assembly 200.

[0048] The plurality of battery cells 100 may be arranged along a longitudinal direction (Y-axis direction) and a width direction (X-axis direction) of the battery pack P. For example, the plurality of battery cells 100 may be arranged in a substantially matrix shape.

[0049] The battery cells 100 are secondary batteries and may be cylindrical secondary batteries, pouch-type secondary batteries, or prismatic secondary batteries. Hereinafter, in this embodiment, the battery cells 100 will be described as being cylindrical secondary batteries.

[0050] The battery cell 100 will be described in more detail below with reference to the associated drawings.

[0051] FIG. 3 is a diagram for explaining a battery cell included in the battery pack shown in FIG. 2, FIG. 4 is a partial cross-sectional view showing the internal structure of the battery cell of FIG. 3, FIG. 5 is a partial cross-sectional view showing the upper structure of the battery cell of FIG. 3, FIG. 6 is a partial cross-sectional view showing the lower structure of the battery cell of FIG. 3, and FIG. 7 is a bottom view of the battery cell of FIG. 3.

[0052] 3 to 7, the battery cell 100 includes an electrode assembly 10, a battery can 20, a cap plate 30, and a first electrode terminal 40. In addition to the above-mentioned components, the battery cell 100 may further include an insulating gasket 50 and / or an upper current collecting plate 60 and / or an insulating plate 70 and / or a lower current collecting plate 80 and / or a sealing gasket 90.

[0053] The electrode assembly 10 includes a first electrode plate having a first polarity, a second electrode plate having a second polarity, and a separator interposed between the first and second electrode plates. The first electrode plate is a positive or negative electrode plate, and the second electrode plate is an electrode plate having an opposite polarity to the first electrode plate.

[0054] The electrode assembly 10 may be in the form of a jelly roll. That is, the electrode assembly 10 may be manufactured by sequentially stacking a first electrode plate, a separator, and a second electrode plate at least once, and winding the stacked body around a winding center C. In this case, a separator may be provided on the outer periphery of the electrode assembly 10 to insulate it from the battery can 20.

[0055] The first electrode plate includes a first electrode collector and a first electrode active material applied to one or both sides of the first electrode collector. An uncoated portion where the first electrode active material is not applied exists at one end of the first electrode collector in the width direction (direction parallel to the Z axis). The uncoated portion functions as a first electrode tab. The first electrode tab 11 is provided at the upper part of the electrode assembly 10 housed in the battery can 20 in the height direction (direction parallel to the Z axis).

[0056] The second electrode plate includes a second electrode collector and a second electrode active material applied to one or both sides of the second electrode collector. An uncoated portion where the second electrode active material is not applied exists at the other end in the width direction (direction parallel to the Z axis) of the second electrode collector. The uncoated portion functions as a second electrode tab 12. The second electrode tab 12 is provided at the lower part in the height direction (direction parallel to the Z axis) of the electrode assembly 10 accommodated in the battery can 20.

[0057] The battery can 20 is a cylindrical container having an opening formed at the bottom and is made of a conductive metal material. The side and top of the battery can 20 are integrally formed. The top of the battery can 20 has a substantially flat shape. The battery can 20 accommodates the electrode assembly 10 through an opening formed at the bottom, and also accommodates an electrolyte.

[0058] The battery can 20 is electrically connected to the second electrode tab 12 of the electrode assembly 10. Therefore, the battery can 20 has the same polarity as the second electrode tab 12.

[0059] The battery can 20 may include a beading portion 21 and a crimping portion 22 formed at a lower end thereof. The beading portion 21 is formed at a lower portion of the electrode assembly 10. The beading portion 21 is formed by pressing an outer circumferential surface of the battery can 20. The beading portion 21 prevents the electrode assembly 10, which has a size corresponding to the width of the battery can 20, from slipping out of an opening formed at the lower end of the battery can 20, and may function as a support on which a cap plate 30 is placed.

[0060] The crimping portion 22 is formed under the beading portion 21. The crimping portion 22 is extended and bent to surround the outer circumferential surface of the cap plate 30 disposed under the beading portion 21 and a part of the lower surface of the cap plate 30.

[0061] The cap plate 30 is a component made of a conductive metal material and covers an opening formed at a lower end of the battery can 20. That is, the cap plate 30 constitutes the lower surface of the battery cell 100. The cap plate 30 is placed on a beading portion 21 formed on the battery can 20 and fixed by a crimping portion 22. An airtight gasket 90 may be interposed between the cap plate 30 and the crimping portion 22 of the battery can 20 to ensure airtightness of the battery can 20.

[0062] The cap plate 30 may further include a vent portion 31 formed to prevent an increase in internal pressure due to gas generated inside the battery can 20. The vent portion 31 corresponds to a region of the cap plate 30 that is thinner than a surrounding region. The vent portion 31 is structurally weaker than the surrounding region. Therefore, if an abnormality occurs in the battery cell 100 and the internal pressure increases above a certain level, the vent portion 31 breaks to release the gas generated inside the battery can 20.

[0063] The battery cell 100 according to an embodiment of the present invention has a structure in which both the positive and negative terminals are located at the upper portion, and therefore the structure of the upper portion is more complicated than that of the lower portion. Therefore, in order to smoothly exhaust gas generated inside the battery can 20, a vent portion 31 may be formed in a cap plate 30 forming a lower surface of the battery cell 100.

[0064] The vent portion 31 may be formed continuously in a circular shape on the cap plate 30. However, without being limited thereto, the vent portion 31 may be formed discontinuously in a circular shape on the cap plate 30, or may be formed in a linear shape or in other shapes.

[0065] The first electrode terminal 40 is made of a conductive metal material and is electrically connected to the first electrode tab 11 of the electrode assembly 10 by passing through the upper surface of the battery can 20. Therefore, the first electrode terminal 40 has a first polarity. The first electrode terminal 40 is electrically insulated from the battery can 20 having a second polarity.

[0066] The first electrode terminal 40 includes an exposed terminal portion 41 and an insertion terminal portion 42. The exposed terminal portion 41 is exposed to the outside of the battery can 20. The exposed terminal portion 41 is located at the center of the upper surface of the battery can 20. The insertion terminal portion 42 penetrates the center of the upper surface of the battery can 20 and is electrically connected to the first electrode tab 11. The insertion terminal portion 42 may be rivet-connected to an inner surface of the battery can 20.

[0067] The upper surface of the battery can 20 and the first electrode terminal 40 have opposite polarities and face the same direction. In addition, a step may be formed between the first electrode terminal 40 and the upper surface of the battery can 20. Specifically, when the entire upper surface of the battery can 20 has a flat shape or a shape that protrudes upward at its center, the exposed terminal portion 41 of the first electrode terminal 40 may protrude further upward than the upper surface of the battery can 20. Conversely, when the upper surface of the battery can 20 has a concave shape that is concave downward at its center, i.e., toward the electrode assembly 10, the upper surface of the battery can 20 may protrude further upward than the exposed terminal portion 41 of the first electrode terminal 40.

[0068] The insulating gasket 50 is interposed between the battery can 20 and the first electrode terminal 40 to prevent the battery can 20 and the first electrode terminal 40, which have opposite polarities, from contacting each other. Thus, the upper surface of the battery can 20 having a substantially flat shape can function as the second electrode terminal of the battery cell 100.

[0069] The insulating gasket 50 includes an exposed portion 51 and an inserted portion 52. The exposed portion 51 is interposed between the exposed terminal portion 41 of the first electrode terminal 40 and the battery can 20. The inserted portion 52 is interposed between the inserted terminal portion 42 of the first electrode terminal 40 and the battery can 20. The insulating gasket 50 may be made of, for example, a resin material having insulating properties.

[0070] When the insulating gasket 50 is made of a resin material, the insulating gasket 50 may be coupled to the battery can 20 and the first electrode terminal 40 by thermal fusion. In this case, the airtightness at the coupling interface between the insulating gasket 50 and the first electrode terminal 40 and the coupling interface between the insulating gasket 50 and the battery can 20 may be enhanced.

[0071] The entire upper surface of the battery can 20 , excluding the area occupied by the first electrode terminal 40 and the insulating gasket 50 , corresponds to a second electrode terminal 20 a having an opposite polarity to the first electrode terminal 40 .

[0072] The battery cell 100 according to an embodiment of the present invention includes a first electrode terminal 40 having a first polarity and a second electrode terminal 20a electrically insulated from the first electrode terminal 40 and having a second polarity, on one side of the battery cell in its length direction (parallel to the Z-axis). That is, in the battery cell 100 according to an embodiment of the present invention, since the pair of electrode terminals 40, 20a are positioned in the same direction, when a plurality of battery cells 100 are electrically connected, it is possible to arrange electrical connection parts such as a bus bar assembly 200, which will be described later, only on one side of the battery cell 100. This can simplify the structure of the battery pack P and improve the energy density.

[0073] Hereinafter, the bus bar assembly 200 for electrically connecting to the plurality of battery cells 100 will be described in more detail.

[0074] 2, the busbar assembly 200 may be provided on one side of the battery cell 100, specifically, on the upper side (+Z-axis direction) of the battery cell 100, and may electrically connect the plurality of battery cells 100. The electrical connection of the busbar assembly 200 may be parallel and / or series connection. Hereinafter, in this embodiment, the electrical connection of the busbar assembly 200 may be parallel and / or series connection.

[0075] The bus bar assembly 200 is electrically connected to the first electrode terminal 40 (see FIG. 3) having a first polarity of the plurality of battery cells 100 and the battery can 20 (see FIG. 3) having a second polarity, and may be electrically connected to an external charge / discharge line, etc. through connector terminals 280, 290, etc. Here, the first polarity may be a positive pole, and the second polarity may be a negative pole.

[0076] In the following description of this embodiment, it is assumed that the first electrode terminal 40 is a positive electrode and the second electrode terminal 20a is a negative electrode.

[0077] Hereinafter, the configuration of the bus bar assembly 200 will be described in more detail.

[0078] FIG. 8 is a diagram for explaining the bus bar assembly shown in FIG.

[0079] With further reference to FIG. 8 and FIG. 2, the busbar assembly 200 may include a main busbar unit 210.

[0080] The main busbar unit 210 may be provided in plurality and may be electrically connected to the battery cells 100 disposed at the outermost side in the longitudinal direction (Y-axis direction) of the battery pack P. The main busbar unit 210 may be electrically connected to connector terminals 280 and 290, which will be described later.

[0081] FIG. 9 is a diagram for explaining the connecting busbar unit of the busbar assembly shown in FIG. 8, FIG. 10 is a schematic exploded oblique view of the connecting busbar unit of FIG. 9, FIG. 11 is an enlarged view for explaining main portions of the connecting busbar unit of FIG. 10, FIG. 12 is a diagram for explaining the connection busbar of the connecting busbar unit of FIG. 9, and FIG. 13 is a plan view of main portions of the connection busbar of FIG. 12.

[0082] 9 to 13 and 2, the busbar assembly 200 may include a connecting busbar unit 230.

[0083] The connecting busbar units 230 are disposed between the main busbar units 210 in the longitudinal direction (Y-axis direction) of the battery pack P, are electrically connected to the plurality of battery cells 100, and may cover the plurality of battery cells 100.

[0084] The connecting busbar unit 230 may be provided in a size sufficient to cover all of the battery cells 100, or a plurality of connecting busbar units 230 may be provided to cover the battery cells 100. Hereinafter, in this embodiment, the description will be limited to the case where a plurality of connecting busbar units 230 are provided.

[0085] Each of such multiple interlocking busbar units 230 may include a busbar cover 240 and a connecting busbar 250.

[0086] The bus bar cover 240 may cover a connection bus bar 250, which will be described later. The bus bar cover 240 may be provided in a substantially flat plate shape to cover an upper side of the plurality of battery cells 100. The shape and size of the bus bar cover 240 may vary depending on the number and capacity of the battery cells 100 required by the battery pack P.

[0087] The bus bar cover 240 may be made of an insulating material. For example, the bus bar cover 240 may include a polyimide film. However, the bus bar cover 240 is not limited thereto, and may include other insulating members made of insulating materials.

[0088] The bus bar covers 240 may be provided in a pair and coupled to each other to have corresponding shapes and sizes in the vertical direction (Z-axis direction) of the battery pack P. Here, a connection bus bar 250, which will be described later, may be a single layer and may be inserted between the pair of bus bar covers 240.

[0089] Specifically, the pair of bus bar covers 240 may include a first cover 241 and a second cover 242.

[0090] The first cover 241 may cover one side of a connection bus bar 250 described below. Specifically, the first cover 241 may cover an upper side of a connection bus bar 250 described below. More specifically, the first cover 241 may cover upper sides of a plurality of connection bus bars 250 in an integrated manner.

[0091] The second cover 242 may cover the other side of the connection bus bar 250, which will be described later. Specifically, the second cover 242 may cover the lower side of the connection bus bar 250, which will be described later. More specifically, the second cover 242 may integrally cover the lower sides of the plurality of connection bus bars 250. Such a second cover 242 may be combined with the first cover 241. By combining the first cover 241 and the second cover 242, the plurality of connection bus bars 250 are disposed between the first cover 241 and the second cover 242, and a short circuit can be prevented to ensure safety.

[0092] In such a bus bar cover 240, bus bar holes 243, 244 and a guide hole 246 may be formed.

[0093] The busbar holes 243, 244 may have an opening space of a predetermined size that exposes a series connection portion 253 of a connection busbar 250 described later. Such busbar holes 243, 244 may improve the efficiency of electrical connection, such as a welding process, between the series connection portion 253 of the connection busbar 250 described later and the battery cells 100, and may increase the injection efficiency of a filling member 500 described later.

[0094] The bus bar holes 243 and 244 may be formed to have an opening space larger than the size of the series connection portion 253 so as to further improve the efficiency of electrical connection and the injection efficiency of the filler 500 .

[0095] A plurality of such busbar holes 243, 244 may be provided.

[0096] The plurality of busbar holes 243 , 244 may include a positive busbar hole 243 and a negative busbar hole 244 .

[0097] The positive busbar hole 243 has an opening space of a predetermined size and may be provided in a plurality of pieces. A positive electrode connection part 254 described later may be exposed in the positive busbar hole 243. Here, the positive busbar hole 243 may be formed to have an opening space larger than the size of the positive electrode connection part 254 described later in order to improve process operability and injection efficiency of the filler 500 described later.

[0098] The positive busbar hole 243 can more efficiently guide an electrical connection between a positive electrode connector 254 (described later) and a first electrode terminal 40 (see FIG. 3) which is a positive electrode of the battery cell 100.

[0099] Furthermore, it is possible to significantly improve the injection efficiency of the filling member 500 when injecting a filling member 500 described later through the open space of the positive busbar hole 243. Specifically, since the filling member 500 provided as a potting resin described later can be directly injected from the upper side of the battery pack P downward in the vertical direction (Z-axis direction) through the open space of the positive busbar hole 243, it is possible to significantly improve the injection efficiency between the battery cells 100.

[0100] The negative busbar hole 244 is disposed opposite to the positive busbar hole 243, has a predetermined size of opening space like the positive busbar hole 243, and may be provided in plurality. Here, the negative busbar hole 244 may be formed to have an opening space larger than the size of a negative electrode connection part 256 to be described later in order to improve process operability and injection efficiency of a filler 500 to be described later.

[0101] The negative electrode busbar hole 244 can more efficiently guide an electrical connection between a negative electrode connector 256 (described later) and a second electrode terminal 20a (see FIG. 3) which is the negative electrode of the battery cell 100.

[0102] Furthermore, it is possible to significantly improve the injection efficiency of the filling member 500 when the filling member 500 described later is injected through the open space of the negative busbar hole 244. Specifically, the filling member 500 provided as a potting resin described later can be directly injected in a vertical direction (Z-axis direction) from the upper side of the battery pack P downward through the open space of the negative busbar hole 244, so that the injection efficiency between the battery cells 100 can be significantly improved.

[0103] The guide hole 246 may guide the assembly position of the busbar assembly 200. Specifically, the guide hole 246 may fix the connecting busbar unit 230 to the side structural unit 400 and guide the correct position arrangement of the connecting busbar unit 230.

[0104] A plurality of guide holes 246 may be provided. Bus bar guide protrusions 416 of a side structural unit 400, which will be described later, may be inserted into the plurality of guide holes 246.

[0105] The connection bus bar 250 may be connected in series and in parallel to adjacent battery cells 100 in the longitudinal direction (Y-axis direction) and the width direction (X-axis direction). A plurality of such connection bus bars may be provided to connect a plurality of battery cells 100.

[0106] The connection bus bar 250 may be provided in a strip shape having a predetermined length and width and may be provided in one single layer. Here, the strip shape may be formed to correspond to the arrangement structure of the plurality of battery cells 100. For example, the strip shape may be formed in a cross shape, a diagonal shape, a zigzag shape, or the like, depending on the arrangement structure of the battery cells 100.

[0107] The connection bus bar 250 may be provided on the upper side of the bus bar cover 240 or may be inserted between the pair of bus bar covers 240. Hereinafter, in this embodiment, the description will be limited to the case where the connection bus bar 250 is inserted between the pair of bus bar covers 240 as described above.

[0108] There may be a plurality of such connection bus bars 250. The connection bus bars 250 may be inserted into the bus bar cover 240 and spaced apart from each other by a predetermined distance in the longitudinal direction (Y-axis direction) of the battery pack P.

[0109] The multiple connection bus bars 250 may include a parallel connection portion 252 , a series connection portion 253 , and an interconnection portion 257 .

[0110] The parallel connection part 252 is configured to connect the battery cells 100 in parallel, and may be formed along one of the longitudinal direction (Y-axis direction) and width direction (X-axis direction) of the battery pack P. Specifically, the parallel connection part 252 may be formed along one of the longitudinal direction (Y-axis direction) and width direction (X-axis direction) of the bus bar assembly 200. Hereinafter, in this embodiment, the description will be limited to the case where the parallel connection part 252 is formed along the width direction of the battery pack P, i.e., the width direction (X-axis direction) of the bus bar assembly 200.

[0111] The parallel connection parts 252 may be inserted into the bus bar cover 240 and formed to have a predetermined length along the width direction (X-axis direction) of the battery pack P. The parallel connection parts 252 may be provided in a shape corresponding to the arrangement structure of the battery cells 100 in the width direction (X-axis direction) of the battery pack P so as to improve the efficiency of electrical connection with the battery cells 100. Thus, in the present embodiment, the parallel connection parts 252 may be arranged in a zigzag shape in the width direction (X-axis direction) of the battery pack P.

[0112] The parallel connection part 252 may be made of a conductive material. For example, the parallel connection part 252 may be made of a metal material, such as aluminum or copper. However, the parallel connection part 252 is not limited thereto, and may be made of other materials for electrical connection.

[0113] The series connection part 253 is configured to connect the battery cells 100 in series, and may be formed along the other of the longitudinal direction (Y-axis direction) and width direction (X-axis direction) of the battery pack P. Specifically, the series connection part 253 may be formed along the other of the longitudinal direction (Y-axis direction) and width direction (X-axis direction) of the bus bar assembly 200. Hereinafter, in this embodiment, the description will be limited to the case where the series connection part 253 is formed along the longitudinal direction of the battery pack P, i.e., the longitudinal direction (Y-axis direction) of the bus bar assembly 200.

[0114] The series connection part 253 may include a positive electrode connection part 254 and a negative electrode connection part 256 .

[0115] The positive electrode connector 254 may protrude from an interconnection part 257 (described later) by a predetermined length and be disposed in the positive electrode busbar hole 243. The positive electrode connector 254 may be electrically connected to the positive electrode 40 (see FIG. 3 ) of the battery cell 100. The electrical connection may be performed through a welding process for electrical connection, such as laser welding or ultrasonic welding.

[0116] The connection between the positive electrode connector 254 and the positive electrode 40 of the battery cell 100 is performed in the open space of the positive electrode busbar hole 243, so that a welding process for the connection can be performed immediately in the open space without any additional process during connection.

[0117] The negative electrode connector 256 may be provided on the opposite side of the positive electrode connector 254, protrude from the interconnection part 257 by a predetermined length, and be disposed in the negative electrode busbar hole 244. The negative electrode connector 256 may be electrically connected to the negative electrode 20a (see FIG. 3 ) of the battery cell 100. The electrical connection may be performed through a welding process for electrical connection, such as laser welding or ultrasonic welding.

[0118] The connection between the negative electrode connector 256 and the negative electrode 20a of the battery cell 100 is performed in the open space of the negative electrode busbar hole 244, so that a welding process for the connection can be performed immediately in the open space without any additional process during connection.

[0119] In this manner, the positive electrodes 40 and negative electrodes 20 a of the plurality of battery cells 100 may be electrically connected to the positive electrode connector 254 and the negative electrode connector 256 integrally provided on the single-layer connection bus bar 250 provided in the bus bar assembly 200.

[0120] The interconnection portion 257 may connect between the parallel connection portion 252 and the series connection portion 253. The interconnection portion 257 may be integrally formed with the parallel connection portion 252 and the series connection portion 253 to configure the connection bus bar 250 provided as the single layer.

[0121] Each of the multiple connecting busbar units 230 may include a fusing portion 260.

[0122] The fusing unit 260 may be formed on the connection bus bar 250 and configured to cut off electrical connection of the battery cells 100 in an abnormal situation in both the series direction and the parallel direction. The fusing unit 260 may be configured to physically separate at least a portion of the connection bus bar 250 in an abnormal situation.

[0123] The fusing portion 260 may be integrally formed with the connection bus bar 250. Specifically, the fusing portion 260 may be integrally formed with the interconnection portion 257.

[0124] The fusing unit 260 may be configured to narrow the width of the interconnection unit 257. This is because a region with a relatively high resistance (a region with a narrow cross-sectional area through which current flows) generates a relatively large amount of heat, and thus melts down the material earlier than other regions. Therefore, the fusing unit 260 may be recessed from the interconnection unit 257 by a predetermined depth. Here, the fusing unit 260 may be formed at each corner of the edge of the interconnection unit 257.

[0125] In this embodiment, the fusing unit 260 may cause the width W3 of the interconnection unit 257 between the parallel connection unit 252 and the interconnection unit 257 to be narrower than the width W1 of the parallel connection unit 252. Also, in this embodiment, the fusing unit 260 may cause the width W4 of the interconnection unit 257 between the series connection unit 253 and the interconnection unit 257 to be narrower than the width W2 of the series connection unit 253. That is, the fusing unit 260 forms a busbar neck portion having a relatively thin thickness in the series connection direction. As a result, in this embodiment, the fusing unit 260 may narrow the widths of both the series connection portion and the parallel connection portion of the interconnection unit 257.

[0126] FIG. 14 is a diagram for explaining a fusing portion according to another embodiment of the connection bus bar of FIG. 13, and FIG. 15 is a diagram for explaining a fusing portion according to yet another embodiment of the connection bus bar of FIG.

[0127] 14, the fusing portion 263 may be formed in an angular shape, instead of a round shape as in FIG. 13. Also, referring to FIG. 15, the fusing portion 265 may be formed in the interconnection portion 257 as a hole having a predetermined size that narrows the width of the edge of the interconnection portion 257. As such, the fusing portions 263 and 265 may have various shapes and arrangements that can narrow the width of the interconnection portion 257 connecting the parallel connection portion 252 and the series connection portion 253. In addition, the fusing portion may be formed in a semicircular shape, a notch, a groove, a circular shape, etc. that can narrow the width of the interconnection portion 257.

[0128] Hereinafter, a more specific description will be given of the electrical connection structure of the battery cells 100 through the connection bus bar 250. Meanwhile, in order to more clearly show the connection structure of the connection bus bar 250, the bus bar cover 240 that covers the connection bus bar 250, the cooling unit 300 disposed between the battery cells 100 described below, and the configuration of the side structure unit 400 are not shown in Figs. 16 to 20.

[0129] Fig. 16 is a diagram for explaining the connection between the positive and negative electrodes of the battery cells through the connection bus bar in Fig. 12, and Fig. 17 is a diagram for explaining the electrical connection between the battery cells through the connection bus bar in Fig. 12. As described above, for the sake of convenience of explanation, the bus bar cover 240 that covers the connection bus bar 250, the cooling unit 300 disposed between the battery cells 100, the side structure unit 400, and the like are omitted from Figs. 16 and 17.

[0130] 16 and 17, when the battery cell 100 and the connection bus bar 250 are electrically connected, a height h1 between the positive electrode connector 254 and the negative electrode connector 256 in the height direction (Z-axis direction) of the bus bar assembly 200 (see FIG. 2) may be the same as a height at which the positive electrode 40 protrudes from one side of the battery cell 100.

[0131] As a result, when a worker or the like places the connection bus bar 250 on one side of the battery cell 100, specifically, on the upper side (+Z-axis direction) of the battery cell 100, the positive electrode connecting portion 254 and the negative electrode connecting portion 256 of the connection bus bar 250 can be stably and closely attached to the positive electrode 40 and the negative electrode 20a of the battery cell 100.

[0132] In addition, since the positive electrode connecting portion 254 and the negative electrode connecting portion 256 of the connection bus bar 250 can maximize the contact area with the positive electrode 40 and the negative electrode 20a of the battery cell 100, it is possible to significantly improve welding accuracy while preventing poor welding quality during subsequent welding processes for electrical connection.

[0133] Meanwhile, in the height direction (Z-axis direction) of the bus bar assembly 200, a height h2 of the interconnection part 257 may be greater than the heights of the positive electrode connecting part 254 and the negative electrode connecting part 256. As a result, the interconnection part 257 is disposed sufficiently spaced apart from the positive electrode 40 and the negative electrode 20a of the battery cell 100, thereby further improving electrical safety.

[0134] 18 to 20 are diagrams for explaining an electrical connection / disconnection mechanism through a fusing portion according to an embodiment of the present invention. As described above, for the sake of convenience, the bus bar cover 240 that covers the connection bus bar 250, the cooling unit 300 disposed between the battery cells 100, and the side structure unit 400 are also omitted from the drawings in Figs. 18 to 20.

[0135] 18 to 20, when an abnormal condition occurs in any of the battery cells 100a among the battery cells 100, the fusing unit 260 can cut off the electrical connection of the battery cell 100a in which the abnormal condition occurs in both the series and parallel directions.

[0136] As described above, the fusing portion 260 is formed to narrow the width of the interconnection portion 257 connecting the parallel connection portion 252 and the series connection portion 253. Therefore, when a high current is applied to the connection bus bar 250 side by a battery cell 100a in which an abnormality has occurred, the interconnection portion 257 connected to the battery cell 100a in which an abnormality has occurred is melted down relatively first.

[0137] The fusing unit 260 is formed to narrow the widths of the interconnection units 257 connected to the parallel connection units 252 and the series connection units 253, and therefore, in an abnormal situation, the fusing unit 260 can cut off the parallel connection and the series connection in the area of ​​the interconnection units 257 connected to the parallel connection units 252 and the series connection units 253. In other words, the fusing unit 260 can cut off the parallel connection and the series connection in the area of ​​the interconnection units 257 connected to the parallel connection units 252 and the series connection units 253. As a result, in an abnormal situation, the series connection and the parallel connection can be cut off in the same area by the fusing unit 260.

[0138] In this manner, in the present embodiment, in the event of an abnormal situation, the fusing unit 260 can cut off all series and parallel connections of the battery cell 100a in which the abnormal situation has occurred, and completely isolate the battery cell 100a in which the abnormal situation has occurred from the other battery cells 100.

[0139] Therefore, in this embodiment, when an abnormal situation occurs, it is possible to more quickly prevent damage from spreading in a chain reaction to other battery cells 100 around the battery cell 100a where the abnormal situation occurs.

[0140] Furthermore, since the interconnection part 257 in which the fusing part 260 according to this embodiment is formed is disposed at a predetermined distance from the battery cell 100, damage to the battery cell 100 when the fusing part 260 generates heat can be minimized, thereby maximizing the safety of the battery cell 100.

[0141] Meanwhile, the fusing unit 260 may be configured to sequentially cut off the electrical connection of the parallel connection unit 252 and the series connection unit 253 connected to the battery cell 100a in which an abnormality occurs.

[0142] When an abnormal situation occurs, the fusing unit 260 may first melt the connection portion of the interconnection unit 257 with the parallel connection unit 252 as shown in Fig. 19, and then melt the connection portion of the interconnection unit 257 with the series connection unit 253 as shown in Fig. 20. The sequential melting of the parallel connection unit 252 and the series connection unit 253 in the interconnection unit 257 may be such that the connection portion at the series connection unit 253 is first cut and then the connection portion at the parallel connection unit 252 is cut, depending on the current path. Furthermore, the series connection unit 253 and the parallel connection unit 252 may be simultaneously cut depending on the current path.

[0143] In such an abnormal situation, the sequential interruption of the series connection and parallel connection through the fusing unit 260 is also performed in the same region, the interconnection unit 257, thereby minimizing the effect of heat generation in the fusing unit 260 on the battery cell 100.

[0144] With further reference to FIG. 2, the bus bar assembly 200 may include a sensing interconnection board 270 and connector terminals 280, 290.

[0145] The sensing interconnection board 270 may be connected to an external sensing line and provided at one end (-Y axis direction) of the battery pack P. The position of the sensing interconnection board 270 may be changed depending on the design, etc., and may be provided at another position where the sensing interconnection board 270 can be connected to the external sensing line. Furthermore, a plurality of the sensing interconnection boards 270 may be provided depending on the number and capacity of the battery cells 100 of the battery pack P.

[0146] The sensing interconnection board 270 may be provided to be exposed to the outside of the battery pack P for connection to the external sensing lines. The external sensing lines may connect the sensing interconnection board 270 to a battery management system (not shown). The battery management system may determine the state of charge of the battery cells based on the voltages of the battery cells.

[0147] The sensing interconnection board 270 may include a thermistor for checking the temperature state of the battery cell 100. The thermistor may be built into the sensing interconnection board 270 or may be separately attached to the outside of the sensing interconnection board 270.

[0148] The connector terminals 280 and 290 may be provided as a pair. The pair of connector terminals 280 and 290 may be used as high voltage connector terminals for connection to an external charge / discharge line.

[0149] With further reference to FIG. 2, the battery pack P may include a cooling unit 300.

[0150] The cooling unit 300 is for cooling the battery cells 100 and is disposed below the busbar assembly 200 (-Z axis direction) and may be disposed between the multiple battery cells 100 along the longitudinal direction (Y axis direction) of the battery pack P.

[0151] A plurality of such cooling units 300 may be provided.

[0152] The plurality of cooling units 300 may be disposed to face the plurality of battery cells 100 in a width direction (X-axis direction) of the battery pack P. Here, the plurality of cooling units 300 may be disposed to contact the facing battery cells 100 in order to enhance cooling performance.

[0153] Such a cooling unit 300 will be described in more detail below.

[0154] FIG. 21 is a diagram for explaining the cooling unit shown in FIG. 2, and FIG. 22 is a cross-sectional view of the cooling unit of FIG.

[0155] 21, 22, and 2, the cooling unit 300 may include a cooling tube 310, a cooling passage 350, and a cooling water inlet / outlet 370.

[0156] The cooling tube 310 is formed to a predetermined length along the longitudinal direction (Y-axis direction) of the battery pack P, is disposed between the plurality of battery cells 100, and may have a cooling flow path 350 therein for circulating cooling water, which will be described later.

[0157] The cooling tubes 310 may be formed in a shape corresponding to outer surfaces of the plurality of battery cells 100 facing each other in a width direction (X-axis direction) of the battery pack P.

[0158] Such a cooling tube 310 may be formed such that a plurality of protrusions 312 and recesses 316 formed in an uneven shape toward the width direction (X-axis direction) of the battery pack P are arranged relative to one another along the longitudinal direction (Y-axis direction) of the battery pack P.

[0159] The cooling tube 310 may be disposed to contact outer surfaces of the battery cells 100 in order to further enhance the cooling performance of the battery cells 100. The cooling tube 310 may be adhered and fixed to the battery cells 100 through a filling member 500 to be described later or a separate adhesive member, etc.

[0160] The cooling flow passage 350 circulates coolant for cooling the battery cells 100, and may be provided in the cooling tube 310 and connected to communicate with a coolant inlet / outlet 370, which will be described later.

[0161] Such cooling channels 350 may include an upper channel 352 , a lower channel 354 , and a connecting channel 356 .

[0162] The upper flow passage 352 may be disposed above the cooling tube 310 so as to be provided near the bus bar assembly 200, and may be formed to a predetermined length along the longitudinal direction (Y-axis direction) of the cooling tube 310. The upper flow passage 352 may be connected to communicate with the cooling water supply port 374 of the cooling water inlet / outlet part 370.

[0163] At least one upper passage 352 may be provided, but in the following description of the present embodiment, in order to ensure cooling performance, a plurality of upper passages 352 will be described.

[0164] The lower flow passage 354 may be disposed below (in the -Z-axis direction) the cooling tube 310, spaced apart from at least one upper flow passage 352, and formed to a predetermined length along the longitudinal direction (in the Y-axis direction) of the cooling tube 310. The lower flow passage 354 may be connected to communicate with the cooling water discharge port 376 of the cooling water inlet / outlet part 370.

[0165] At least one lower passage 354 may be provided, but in the following description of the present embodiment, a plurality of lower passages 354 will be described in order to ensure sufficient cooling performance.

[0166] The connecting flow passage 356 may connect at least one upper flow passage, in this embodiment, a plurality of upper flow passages 352 , and at least one lower flow passage, in this embodiment, a plurality of lower flow passages 354 .

[0167] The connecting passage 356 may be provided at the other end (+Y-axis direction) of the cooling tube 310 opposite the cooling water inlet / outlet 370 so as to maximize the cooling passage 350 .

[0168] In this embodiment, when the cooling water circulates in the cooling passage 350, the cooling water supplied from the cooling water supply port 374 is first supplied to the upper passage 352 disposed near the bus bar assembly 200, and then flows through the connecting passage 356 and the lower passage 354 to the cooling water discharge port 376.

[0169] As a result, in this embodiment, cold cooling water is preferentially supplied to the area near the bus bar assembly 200, which has a relatively high temperature distribution within the battery pack P, thereby significantly improving the cooling performance of the battery cells 100.

[0170] The cooling water inlet / outlet 370 may be connected to the cooling tube 310 so as to communicate with the cooling passage 350 of the cooling tube 310. The cooling water inlet / outlet 370 may be exposed to the outside of a side structural unit 400 (to be described later) and connected to communicate with an external cooling line.

[0171] The coolant inlet / outlet part 370 may be provided on one side (-Y axis direction) in the longitudinal direction (Y axis direction) of the battery pack P. The cooling tube 310 connected to the coolant inlet / outlet part 370 may be formed with a predetermined length from the coolant inlet / outlet part 370 toward the other side (+Y axis direction) of the battery pack P in the longitudinal direction (Y axis direction) of the battery pack P.

[0172] The cooling water inlet / outlet 370 may include an inlet / outlet body 372 , a cooling water supply port 374 , and a cooling water exhaust port 376 .

[0173] The inlet / outlet body 372 may be connected to one end (-Y-axis direction) of the cooling tube 310. The cooling water supply port 374 may be provided in the inlet / outlet body 372 and connected to communicate with the upper passage 352. The cooling water supply port 374 may be connected to communicate with the external cooling line. The cooling water discharge port 376 may be provided in the inlet / outlet body 372 and connected to communicate with the lower passage 354. The cooling water discharge port 376 may be disposed at a predetermined distance from the cooling water supply port 374 and connected to communicate with the external cooling line.

[0174] With further reference to FIG. 2 , the battery pack P may include a side structural unit 400 .

[0175] The side structural unit 400 is made of a plastic resin material, supports the battery cells 100, ensures the rigidity of the battery cells 100, and forms the side appearance of the battery pack P.

[0176] The side structural unit 400 will be described in more detail below with reference to the related drawings.

[0177] 23 is a diagram for explaining the side structural unit shown in FIG. 2, and FIG. 24 is a diagram for explaining the main plate of the side structural unit of FIG.

[0178] 23 and 24, the side structural unit 400 supports the battery cells 100 and ensures the rigidity of the battery cells 100, while forming the outer surface of the battery pack P and functioning as a pack case to form the appearance of the battery pack P (see FIG. 2).

[0179] The side structural unit 400 is formed with a predetermined length along the longitudinal direction (Y-axis direction) of the battery pack P, and can accommodate and support the battery cell 100.

[0180] The side structural unit 400 may include a main plate 410 and an end plate 450 .

[0181] The main plate 410 may be formed to a predetermined length along the longitudinal direction (Y-axis direction) of the battery pack P and may accommodate the battery cells 100 arranged in two rows in the width direction (X-axis direction) of the battery pack P. A plurality of such main plates 410 may be provided and may be arranged at a predetermined distance from each other along the width direction (X-axis direction) of the battery pack P.

[0182] The plurality of main plates 410 ensures the rigidity of the battery cells 100 and the cooling unit 300, while occupying a certain space in the battery pack P (see FIG. 2), thereby reducing the amount of filling member 500 to be injected, which will be described later. Since the filling member 500 containing a silicone resin, which will be described later, is relatively expensive, the plurality of main plates 410 can reduce the amount of silicone resin to be injected, thereby further ensuring price competitiveness during the manufacture of the battery pack P.

[0183] Each of the multiple main plates 410 may include a first cell accommodating portion 411, a second cell accommodating portion 412, a bottom rib 415, a busbar guide protrusion 416, a cooling unit insertion groove 417, and a guide step 418.

[0184] The first cell accommodating portion 411 may be provided in front of the main plate 410 (+X-axis direction) along the longitudinal direction (Y-axis direction) of the main plate 410. The first cell accommodating portion 411 may accommodate the plurality of battery cells 100 arranged in the longitudinal direction (Y-axis direction) of the battery pack P. Therefore, a plurality of the first cell accommodating portions 411 may be provided in front of the main plate 410 (+X-axis direction).

[0185] Each of the plurality of first cell accommodating portions 411 may be provided with a concave shape corresponding to an outer surface of the battery cell 100 and may at least partially surround the outer surface of the battery cell 100.

[0186] The second cell accommodating portion 412 may be provided at the rear (-X-axis direction) of the main plate 410 along the longitudinal direction (Y-axis direction) of the main plate 410. Such a second cell accommodating portion 412 may accommodate the plurality of battery cells 100 arranged in the longitudinal direction (Y-axis direction) of the battery pack P. Therefore, a plurality of the second cell accommodating portions 412 may be provided at the rear (-X-axis direction) of the main plate 410.

[0187] Each of the plurality of second cell accommodating portions 412 may be provided with a concave shape corresponding to an outer surface of the battery cell 100 and may at least partially surround the outer surface of the battery cell 100.

[0188] The plurality of second cell accommodating portions 412 may be arranged alternately with the plurality of first cell accommodating portions 411 in the front-rear direction (X-axis direction) of the main plate 410 so as to accommodate a maximum number of battery cells 100, which are cylindrical secondary batteries.

[0189] The bottom rib 415 is provided on the bottom of the main plate 410 and can support the bottom of the battery cell 100 when the battery cell 100 is received in the main plate 410 .

[0190] The bottom rib 415 may be formed to protrude downward (in the −Z axis direction) from the bottom of the battery cell 100 when the battery cell 100 is accommodated in the main plate 410.

[0191] The bus bar guide protrusion 416 is for fixing the connecting bus bar unit 230 when assembling the bus bar assembly 200, and is provided on the upper surface of the main plate 410, and at least one bus bar guide protrusion 416 may be provided. Hereinafter, the present embodiment will be described in terms of a case where a plurality of bus bar guide protrusions 416 are provided.

[0192] When assembling the busbar assembly 200, the busbar guide protrusions 416 may be inserted into the guide holes 246 of the busbar cover 240 to guide the correct positioning of the connecting busbar unit 230. Since the connecting busbar unit 230 is inserted and fixed into the busbar guide protrusions 416, a welding process for electrical connection of the busbar assembly 200 may be more stably performed and the welding quality during the welding process may be further improved.

[0193] The cooling unit insertion groove 417 is for receiving an end of the cooling unit 300 and may be provided at an end in the longitudinal direction (Y-axis direction) of the main plate 410. The end of the cooling unit 300 is disposed in the cooling unit insertion groove 417 when the main plate 410 is assembled, and is more stably fixed.

[0194] The guide steps 418 may be protruded at a predetermined height from both upper ends in the longitudinal direction (Y-axis direction) of the main plate 410. When the assembly of the side structural unit 400 is completed by combining the main plate 410 with an end plate 450 described below, the guide steps 418 may form the periphery of the side structural unit 400 together with end guide steps 458 of an end plate 450 described below.

[0195] The end plates 450 may be provided in a pair on both sides of the outermost edge in the width direction (X-axis direction) of the side structural unit 400. The pair of end plates 450 may accommodate and support the battery cells 100 together with the main plate 410 disposed opposite to each other.

[0196] The pair of end plates 450 may be provided with terminal holes 456 and end guide steps 458 .

[0197] The terminal holes 456 are for receiving the connector terminals 280 , 290 and may be provided at one end of the end plate 450 .

[0198] The end guide step 458 may be formed along the upper edge of the end plate 450 and protrude at the same height as the guide step 418. The end guide step 458 may form the periphery of the side structural unit 400 together with the guide step 418 of the main plate 410 when the assembly of the side structural unit 400 is completed.

[0199] Hereinafter, the coupling structure between the battery cell 100 and the cooling unit 300 through the side structural unit 400 will be described in more detail.

[0200] 25 and 26 are diagrams for explaining a coupling structure between the battery cell and the cooling unit through the side structure unit of FIG. 23. FIG.

[0201] 25 and 26, first, the cooling tube 310 of the cooling unit 300 is sandwiched between the battery cells 100 arranged in two rows in the width direction (X-axis direction) of the battery pack P (see FIG. 2) among the battery cells 100. In this manner, in the front-rear direction (X-axis direction) of the battery cells 100 between which the cooling tube 310 is sandwiched, the side structural unit 400 can accommodate the opposing battery cell 100.

[0202] Specifically, an end plate 450 disposed at the outermost portion in the width direction (X-axis direction) of the battery pack P (see FIG. 2), a battery cell 100, a cooling tube 310, a battery cell 100, and a main plate 410 may be disposed, and then the battery cell 100, the cooling tube 310, the battery cell 100, and the main plate 410 may be disposed and coupled again in this order. Then, an end plate 450 disposed at the outermost portion on the opposite side in the width direction (X-axis direction) of the battery pack P (see FIG. 2) may be finally disposed and coupled to complete the coupling of the side structural unit 400, so that the battery cell 100 and the cooling unit 300 may be accommodated in the side structural unit 400.

[0203] Here, both ends of the cooling unit 300 are inserted into the cooling unit insertion grooves 417 when the main plates 410 are joined together and when the main plate 410 is joined to the end plate 450, thereby preventing interference with the cooling unit 300 and more stably fixing the cooling unit 300.

[0204] Meanwhile, a coolant inlet / outlet 370 provided at one end of the cooling unit 300 may be disposed protruding outward from the side structural unit 400 in order to be connected to an external cooling line or the like.

[0205] The side structural unit 400 according to this embodiment may form a side outer structure of the battery pack P (see FIG. 2) while accommodating the battery cells 100 and the cooling unit 300 through the coupling between the main plate 410 and the end plate 450. That is, the side structural unit 400 may function as a pack case that forms the exterior of the battery pack P.

[0206] As a result, the battery pack P (see FIG. 1) according to this embodiment can omit a separate additional pack case or pack housing structure through the side structural unit 400, thereby reducing manufacturing costs and at the same time reducing the overall size of the battery pack P and further increasing the energy density.

[0207] FIG. 27 is a diagram for explaining the positional relationship between the battery cells and the cooling unit through the side structure unit of FIG. 23. FIG.

[0208] Referring to FIG. 27, the distance A between the center of the battery cell 100 provided in the first cell accommodating portion 411 of the main plate 410 and the center of the battery cell 100 provided in the second cell accommodating portion 412 is a distance set for close contact with the main plate 410 and may be changed depending on the thickness of the main plate 410.

[0209] A distance B between the centers of adjacent battery cells 100 in contact with one side of the cooling tube 310 is a distance set to set a contact angle between the battery cell 100 and the cooling tube 310 to a predetermined angle, for example, 60 degrees, and may be changed in conjunction with a distance C described below. A distance C between the centers of adjacent battery cells 100 disposed opposite each other with the cooling tube 310 interposed therebetween is a distance reflecting a thickness of the cooling tube 310, and may be determined in conjunction with the distance B between the centers of adjacent battery cells 100 in contact with one side of the cooling tube 310.

[0210] The distances A to C may be set as optimal distances for closer adhesion between the battery cell 100 and the cooling tube 310 and between the battery cell 100 and the side structural unit 400 .

[0211] Meanwhile, ends of the first cell accommodating portion 411 and the second cell accommodating portion 412 of the main plate 410 may be formed shorter than one surface of the battery cell 100 that contacts the cooling tube 310 to prevent interference with the opposing cooling tube 310. Specifically, ends of the first cell accommodating portion 411 and the second cell accommodating portion 412 may be disposed to be spaced apart from the cooling tube 310 to have a predetermined gap therebetween.

[0212] 28 is a diagram showing the bottom surface of the side structural unit of FIG. 23 when a battery cell is coupled to the side structural unit, and FIG. 29 is an enlarged bottom view of a main portion of the side structural unit of FIG.

[0213] 28 and 29, the bottom rib 415 of the side structural unit 400 may be provided to protrude further downward (in the -Z-axis direction) than the bottom of the battery cell 100 and not interfere with the vent portion 31 of the battery cell 100. Thus, when gas is discharged through the vent portion 31 due to overheating of the battery cell 100, the gas can be discharged more quickly without interference from the bottom rib 415.

[0214] Furthermore, the bottom rib 415 is provided to cover one side of the bottom of the battery cell 100, so that the battery cell 100 can be more firmly fixed within the side structural unit 400 when the battery cell 100 is received in the side structural unit 400.

[0215] With further reference to FIG. 2, the battery pack P may include a filling member 500.

[0216] The filling member 500 may be filled in a space between the cooling unit 300 and the plurality of battery cells 100 in a height direction (Z-axis direction) of the battery pack P. Meanwhile, in FIG. 2, the filling member 500 is shown by a dotted line in a rectangular parallelepiped shape for ease of understanding, but the filling member 500 may be filled in the entire space between the cooling unit 300 and the plurality of battery cells 100.

[0217] The filling member 500 covers the upper and lower sides of the battery pack P (see FIG. 2) and may form a pack case structure of the battery pack P together with the side structural unit 400.

[0218] In addition, the filling member 500 may more stably fix the battery cells 100 and at the same time, increase the heat dissipation efficiency of the battery cells 100, thereby further improving the cooling performance of the battery cells 100.

[0219] The filling member 500 may include a potting resin. The potting resin may be formed by injecting a loose resin material into the battery cells 100 and hardening it. Here, the resin material may be injected at room temperature of about 15° C. to 25° C. to prevent thermal damage to the battery cells 100.

[0220] Specifically, the filling member 500 may include a silicone resin, but is not limited thereto, and the filling member 500 may include other resin materials capable of improving the fixing and heat dissipation efficiency of the battery cells 100, in addition to the silicone resin.

[0221] More specifically, the filling member 500 covers a portion of the battery cell 100 that is not in contact with the cooling tube 310, thereby guiding the thermal balance of the battery cell 100 and preventing uneven cooling of the battery cell 100, thereby preventing local deterioration of the battery cell 100. In addition, by preventing local deterioration of the battery cell 100, the safety of the battery cell 100 can be significantly improved.

[0222] In addition, the filling member 500 may act as an insulator to prevent current flow to an adjacent battery cell 100 when at least one specific battery cell 100 among the plurality of battery cells 100 is damaged due to an abnormal condition.

[0223] In addition, the filling member 500 may include a material having high specific heat performance. Thus, the filling member 500 increases thermal mass, and delays a temperature rise of the battery cell 100 even in a situation such as rapid charging and discharging of the battery cell 100, thereby preventing a rapid temperature rise of the battery cell 100.

[0224] Also, the filling member 500 may include glass bubbles. The glass bubbles may reduce the specific gravity of the filling member 500, thereby increasing the energy density per weight.

[0225] In addition, the filling member 500 may include a material having high heat resistance. Thus, when a thermal event such as overheating occurs in at least one specific battery cell 100 among the plurality of battery cells 100, the filling member 500 can effectively prevent thermal runaway from occurring in the adjacent battery cell.

[0226] In addition, the filling member 500 may include a material having high flame retardancy. Thus, the filling member 500 may minimize the risk of fire when a thermal event such as overheating occurs in at least one specific battery cell 100 among the plurality of battery cells 100.

[0227] The filling member 500 may be filled in the busbar assembly 200 in addition to the battery cells 100. Specifically, the filling member 500 may be filled in the busbar assembly 200 so as to cover an upper side of the busbar assembly 200.

[0228] Here, the filling member 500 may be continuously filled between the bus bar assembly 200 and the battery cell 100 in the vertical direction (Z-axis direction) of the battery cell 100 without any disconnection or separation space between the bus bar assembly 200 and the battery cell 100.

[0229] As described above, the filling member 500 according to the present embodiment is continuously filled between the battery cells 100 and the bus bar assemblies 200 without interruption, thereby realizing uniform heat dispersion without variations in heat dispersion in the region between the battery cells 100 and the bus bar assemblies 200, and significantly improving the cooling performance of the battery pack P.

[0230] Furthermore, the filling member 500 may be filled in a portion other than the outer surface of the side structural unit 400. Here, the filling member 500 may be continuously filled in the battery cells 100, the bus bar assemblies 200, and the side structural unit 400 without interruption. As a result, the cooling performance of the battery pack P may be further improved.

[0231] Hereinafter, the formation of the pack case structure by injecting the filling material 500 will be described in more detail.

[0232] 30 to 32 are diagrams for explaining the formation of the pack case structure through injection of the filling material shown in FIG.

[0233] 30 to 32, an operator may inject and apply the filling member 500 containing the silicone resin using a resin injection device I, thereby forming upper and lower pack case structures of the battery pack P (see FIG. 2) through the filling member 500 containing the resin material. Specifically, the filling member 500 may be filled up to a protruding height h of the bottom rib 415 while covering an upper side of the bus bar assembly 200 on the upper side (+Z axis direction) of the battery pack P and covering bottoms of the battery cells 100 on the lower side (-Z axis direction) of the battery pack P. Here, the protruding height h of the bottom rib 415 may be designed to a predetermined height taking into consideration the injection amount of the filling member 500.

[0234] During the injection and application process of the filling member 500 using the resin injection device I, an injection guider G may be provided at the bottom of the side structure unit 400 to prevent resin from flowing downward (in the -Z axis direction) when the filling member 500 is injected. The injection guider G may be made of a Teflon material or the like for easy detachment after the filling member 500 is hardened.

[0235] During the injection and application process of the filling member 500, the side structural unit 400, together with the injection guider G, may serve as a formwork for supporting the battery cell 100 and the cooling unit 300 and preventing the resin from flowing out.

[0236] As a result, in this embodiment, the side structure unit 400 eliminates the need for an additional injection guide jig structure in the side direction during the injection and application process of the filling material 500, thereby significantly improving work efficiency while reducing manufacturing costs.

[0237] In addition, the guide step 418 and the end guide step 458 formed on the upper edge of the side structural unit 400 increase the injection accuracy of the filling member 500 when injecting the filling member 500, making it easier to inject the filling member 500 so that it more reliably covers the bus bar assembly 200, and also effectively preventing the filling member 500 from overflowing.

[0238] Here, since the side structural unit 400 exposes components connected to external devices such as the sensing interconnection board 270, the connector terminals 280, 290, and the cooling water inlet / outlet 370 to the outside, there are no problems such as interference with these components when the filling material 500 is injected or applied.

[0239] As a result, in this embodiment, the pack case structure of the battery pack P (see FIG. 1) is formed through the side structural unit 400 and the filling member 500, which simplifies the assembly process of the battery pack P compared to the conventional case in which the pack case structure is formed as a complex assembly of multiple plates, significantly reducing manufacturing costs and ensuring price competitiveness.

[0240] Furthermore, according to the present embodiment, through the pack case structure formed by the side structural unit 400 and the filling member 500, it is possible to reduce the size of the entire battery pack P and significantly increase the energy density, compared to a conventional pack case structure provided as a cell frame structure including an assembly of a plurality of plates.

[0241] FIG. 33 is a diagram for explaining a vehicle according to another embodiment of the present invention.

[0242] Referring to FIG. 33, the vehicle V may be an electric vehicle or a hybrid vehicle and may include at least one battery pack P as described above as an energy source.

[0243] In this embodiment, since the above-mentioned battery pack P is provided with a compact structure having high energy density, when it is installed in an automobile V, it is easy to realize a modular structure of multiple battery packs P, and a relatively high degree of freedom in installation can be ensured even in the various shapes of internal spaces of the automobile V.

[0244] Through the various embodiments described above, it is possible to provide a battery pack P that can improve energy density and ensure rigidity, and a vehicle V including the battery pack P.

[0245] In addition, through the various embodiments described above, it is possible to provide a battery pack P and a vehicle V including the same that can improve price competitiveness and manufacturing efficiency.

[0246] Furthermore, through the various embodiments described above, it is possible to provide a battery pack P having improved cooling performance and a vehicle V including the same.

[0247] Although a preferred embodiment of the present invention has been illustrated and described above, the present invention is not limited to the above-mentioned specific embodiment, and various modifications may be made by a person having ordinary skill in the art to which the present invention pertains without departing from the gist of the present invention as claimed in the claims, and such modifications should not be understood individually from the technical ideas and prospects of the present invention. [Explanation of symbols]

[0248] 100 Battery Cells 200 Busbar Assembly 250 Connection busbar 260, 263, 265 Fusing section P Battery pack

Claims

1. A battery pack comprising: A plurality of battery cells arranged along a longitudinal direction and a width direction of the battery pack; a bus bar assembly disposed on one side of the plurality of battery cells and electrically connecting the plurality of battery cells; Including, The bus bar assembly includes: A connection bus bar connected in series and in parallel to adjacent battery cells in the longitudinal direction and the width direction; a fusing portion formed on the connection bus bar and configured to cut off electrical connection of the battery cell in which an abnormality occurs in both a series direction and a parallel direction; Including, The connection busbar is provided in a single layer in the form of a strip having a predetermined length and width, The connection bus bar is a parallel connection portion formed along one of the longitudinal direction and the width direction and configured to connect the battery cells in parallel; a series connection portion formed along the other of the longitudinal direction and the width direction and configured to connect the battery cells in series; an interconnection portion connecting the parallel connection portion and the series connection portion; Including, The battery pack, wherein the fusing portion is integrally formed with the interconnection portion.

2. The battery pack according to claim 1 , wherein the fusing portion is integrally formed with the connection bus bar.

3. The battery pack according to claim 1 , wherein the fusing portion is configured to narrow a width of the interconnection portion.

4. The battery pack according to claim 1 , wherein the fusing portion is recessed from the interconnection portion by a predetermined depth.

5. The battery pack according to claim 1 , wherein the fusing portion is formed at each corner of an edge portion of the interconnection portion.

6. The battery pack according to claim 1 , wherein the fusing portion is formed in a hole shape having a predetermined size that narrows a width of an edge portion of the interconnection portion.

7. The battery pack of claim 1 , wherein the fusing unit sequentially cuts off electrical connections of the parallel connection unit and the series connection unit connected to the battery cell in which the abnormality occurs.

8. The series connection portion is a positive electrode connecting portion extending from the interconnection portion by a predetermined length; a negative electrode connecting portion provided on the opposite side of the positive electrode connecting portion and extending from the interconnection portion by a predetermined length; 10. The battery pack of claim 1 , comprising:

9. 9. The battery pack of claim 8, wherein a height between the positive electrode connector and the negative electrode connector in a height direction of the bus bar assembly is equal to a height of a positive electrode protruding from one surface of the battery cell.

10. The battery pack according to claim 9 , wherein a height of the interconnection portion is greater than heights of the positive electrode connecting portion and the negative electrode connecting portion in a height direction of the bus bar assembly.

11. The battery pack according to claim 1 , wherein the bus bar assembly includes a bus bar cover covering the connection bus bar.

12. The bus bar covers are provided in pairs, The battery pack according to claim 11 , wherein the connecting bus bar is inserted between the pair of bus bar covers.

13. The pair of bus bar covers are a first cover for covering one side of the connection bus bar; a second cover coupled to the first cover and covering the other side of the connection bus bar; 13. The battery pack of claim 12, comprising:

14. The battery pack according to claim 11 , wherein the bus bar cover is formed with a bus bar hole having an opening space of a predetermined size for exposing the series connection portion.

15. The battery pack according to claim 14 , wherein the bus bar hole is formed to have an opening space larger than a size of the series connection portion.

16. The battery pack of claim 11 , wherein the bus bar cover comprises an insulating material.

17. 17. The battery pack of claim 16, wherein the bus bar cover comprises a polyimide film.

18. The connection bus bar is provided in a plurality of pieces, The battery pack according to claim 11 , wherein the bus bar cover is provided to cover the plurality of connection bus bars.

19. The battery pack according to claim 11 , wherein the bus bar cover is formed with a guide hole for guiding an assembly position of the bus bar assembly.

20. The battery pack according to claim 1 , wherein the strip shape is formed to correspond to an arrangement structure of the plurality of battery cells.

21. A motor vehicle comprising at least one battery pack described in any one of claims 1 to 20.

22. 1. A busbar assembly for electrically connecting battery cells of a battery pack, comprising: A strip-shaped connection bus bar having a predetermined length and width and configured to be connected in series and in parallel with the battery cells; a fusing portion formed on the connection bus bar and configured to cut off electrical connection of the battery cell in which an abnormality occurs in both a series direction and a parallel direction; Including, The connection busbar is provided in a single layer, The connection bus bar is a parallel connection portion formed along one of a longitudinal direction and a width direction of the bus bar assembly and configured to connect the battery cells in parallel; a series connection portion formed along the other of the longitudinal direction and the width direction of the bus bar assembly and configured to connect the battery cells in series; an interconnection portion connecting the parallel connection portion and the series connection portion; Including, A busbar assembly, wherein the fusing portion is integrally formed with the interconnection portion.

23. The busbar assembly of claim 22 , wherein the fusing portion is integrally formed with the connecting busbar.

24. The busbar assembly of claim 22 , wherein the fusing portion is configured to narrow a width of the interconnection portion.

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