CN117397096A

CN117397096A - Battery pack and vehicle comprising same

Info

Publication number: CN117397096A
Application number: CN202280038945.5A
Authority: CN
Inventors: 吴侊根; 杨镇浯; 郑仁赫; 崔海远
Original assignee: LG Energy Solution Ltd
Current assignee: LG Energy Solution Ltd
Priority date: 2021-10-12
Filing date: 2022-09-29
Publication date: 2024-01-12

Abstract

A battery pack according to an embodiment of the present invention includes: a plurality of battery cells; a bus bar assembly having a first side and a second side, wherein the second side of the bus bar assembly is disposed on a first side of the plurality of battery cells and the bus bar assembly is electrically connected to the plurality of battery cells; a cooling unit disposed at the second side of the bus bar assembly and arranged between the plurality of battery cells in a length direction of the battery pack; and a side structural unit configured to accommodate the cooling unit and the plurality of battery cells and fix both ends of the cooling unit.

Description

Battery pack and vehicle comprising same

Technical Field

The present disclosure relates to a battery pack and a vehicle including the battery pack.

The present application claims the benefits of korean patent application 10-2021-0135354 filed on 10-12 of 2021 and korean patent application 10-2022-0101128 filed on 8-12 of 2022, the disclosures of which are incorporated herein by reference in their entireties

Background

The secondary battery is very suitable for various products and exhibits excellent electrical properties (e.g., high energy density, etc.), and is widely used not only for portable devices but also for Electric Vehicles (EVs) or Hybrid Electric Vehicles (HEVs) driven by a power source. Since the use of fossil fuel can be greatly reduced in the course of energy consumption and no by-products are generated, secondary batteries are attracting attention as new energy sources for improving environmental protection and energy efficiency.

Secondary batteries that are widely used at present include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and the like. The operating voltage of the unit secondary battery cell (i.e., the unit cell) is about 2.5V to 4.5V. Thus, if a higher output voltage is required, multiple battery cells may be connected in series to configure the battery pack. In addition, a plurality of battery cells may be connected in parallel to configure the battery pack according to the charge/discharge capacity required for the battery pack. Accordingly, the number of battery cells included in the battery pack may be differently set according to a desired output voltage or a desired charge/discharge capacity.

In addition, when a plurality of battery cells are connected in series or in parallel to configure a battery pack, it is common to first configure a battery module including at least one battery cell and then configure the battery pack or battery rack by using at least one battery module and adding other components.

In general, a conventional battery pack is configured to include a plurality of battery cells and a cell frame for accommodating the plurality of battery cells. Conventional cell frames are typically configured as an assembly of multiple plates, such as front, rear, side, lower and upper plates, to accommodate multiple battery cells and ensure rigidity.

However, the conventional battery pack has no advantages in terms of cost competitiveness and manufacturing efficiency because of an increase in manufacturing costs and a complicated assembly process due to characteristics of a cell frame structure configured as an assembly of a plurality of plates.

Further, since the size of the entire battery pack increases according to the cell frame structure of the assembly configured as a plurality of plates, the conventional battery pack does not have an advantage in terms of energy density.

Disclosure of Invention

Technical problem

Accordingly, the present disclosure relates to providing a battery pack capable of securing rigidity while improving energy density, and a vehicle including the battery pack.

Further, the present disclosure relates to providing a battery pack capable of improving cost competitiveness and manufacturing efficiency, and a vehicle including the battery pack.

Further, the present disclosure relates to providing a battery pack capable of improving cooling performance and a vehicle including the battery pack.

Technical proposal

In one aspect of the present disclosure, there is provided a battery pack including: a plurality of battery cells; a bus bar assembly having a first side and a second side, the second side of the bus bar assembly being disposed to the first side of the plurality of battery cells and electrically connected to the plurality of battery cells; a cooling unit disposed at the second side of the bus bar assembly and arranged between the plurality of battery cells along a longitudinal direction of the battery pack; and a side structural unit configured to accommodate the cooling unit and the plurality of battery cells, wherein opposite ends of the cooling unit are fixed to the side structural unit.

Preferably, the cooling unit may include: a cooling tube having a predetermined length in the longitudinal direction of the battery pack and disposed between the plurality of battery cells; a cooling channel disposed in the cooling tube and configured to circulate a cooling fluid for cooling the plurality of battery cells; and a cooling fluid inlet/outlet portion connected to the cooling pipe to communicate with the cooling passage.

Preferably, the cooling pipe may be formed to have a shape corresponding to outer surfaces of the plurality of battery cells facing the cooling pipe in the width direction of the battery pack.

Preferably, the cooling pipe may include a plurality of protrusions and a plurality of recesses that are respectively formed convexly and concavely in the width direction of the battery pack and are alternately arranged along the longitudinal direction of the battery pack.

Preferably, the cooling passage may include: at least one upper channel provided at an upper side of the cooling tube to be provided in the vicinity of the bus bar assembly; at least one lower channel provided at a lower side of the cooling tube to be spaced apart from the at least one upper channel; and a connection channel configured to connect the at least one lower channel and the at least one upper channel.

Preferably, the side structural units may have cooling unit insertion grooves provided at opposite ends of the side structural units to fix the opposite ends of the cooling units, respectively.

Preferably, the cooling pipe of the cooling unit may be interposed between the plurality of battery cells arranged in front and rear two rows in the width direction of the battery pack.

Preferably, the opposite ends of the cooling unit may be inserted into the cooling unit insertion grooves provided at the opposite ends of the side structural units.

Preferably, the cooling fluid inlet/outlet portion may be provided to protrude out of the side structural unit.

Preferably, at least one end of the side structural unit may be formed to be shorter than one surface of the plurality of battery cells, which is in contact with the cooling tube.

Preferably, a filling member may be filled in a space between the cooling unit and the plurality of battery cells.

Preferably, the filling member may be made of potting resin.

Preferably, the filling member may be made of silicone.

Preferably, the filling member may be filled in the bus bar assembly to cover the first side of the bus bar assembly.

In one aspect of the present disclosure, a battery pack housing structure including at least one battery pack is provided.

In one aspect of the present disclosure, a vehicle is provided that includes a battery pack housing structure, and a longitudinal direction of the at least one battery pack may be arranged approximately perpendicular to a length direction of the vehicle such that the side structural units provide protection for the plurality of battery cells during a front or rear collision of the vehicle.

Preferably, the plurality of battery cells may be compressed in a height direction of the cylindrical can of each of the plurality of battery cells.

Further, in an aspect of the present disclosure, there is provided a battery pack including: a cooling unit having convex and concave portions alternately arranged in a longitudinal direction of the battery pack; a plurality of battery cells arranged in two groups along the longitudinal direction of the battery pack, a first group being arranged on a first side of the cooling unit and a second group being arranged on a second side of the cooling unit; a side structural unit disposed in a longitudinal direction of the battery pack, the side structural unit including a first main plate and a second main plate separated from each other, wherein the first main plate accommodates a plurality of battery cells of the first group and the second main plate accommodates a plurality of battery cells of the second group, and curvatures of the convex portion and the concave portion correspond to curvatures of the plurality of battery cells.

Preferably, each of the first and second main plates may be closest to the cooling unit at a respective convex portion.

Preferably, each battery cell may contact only one of the first main board and the second main board at a first side, and contact one recess of the cooling unit at a second side.

Advantageous effects

According to the various embodiments described above, it is possible to provide a battery pack capable of securing rigidity while improving energy density, and a vehicle including the battery pack.

Further, according to the various embodiments described above, a battery pack capable of improving cost competitiveness and manufacturing efficiency, and a vehicle including the battery pack can be provided.

Further, according to the various embodiments described above, a battery pack capable of improving cooling performance and a vehicle including the battery pack can be provided.

Drawings

The accompanying drawings illustrate example embodiments of the present disclosure and, together with the foregoing disclosure, serve to provide a further understanding of the technical features of the present disclosure, and thus the present disclosure is not to be construed as limited to the accompanying drawings.

Fig. 1 is a diagram for illustrating a battery pack according to an embodiment of the present disclosure.

Fig. 2 is an exploded perspective view illustrating the battery pack of fig. 1.

Fig. 3 is a diagram for illustrating battery cells of the battery pack of fig. 2.

Fig. 4 is a partial sectional view illustrating an internal structure of the battery cell of fig. 3.

Fig. 5 is a partial sectional view illustrating a upper structure of the battery cell of fig. 3.

Fig. 6 is a partial sectional view illustrating a lower structure of the battery cell of fig. 3.

Fig. 7 is a bottom view illustrating the battery cell of fig. 3.

Fig. 8 is a view for illustrating a bus bar assembly of the battery pack of fig. 2.

Fig. 9 is a view for illustrating a connection bus bar unit of the bus bar assembly of fig. 8.

Fig. 10 is an exploded perspective view illustrating the connection bus bar unit of fig. 9.

Fig. 11 is an enlarged view for illustrating a main portion of the connection bus bar unit of fig. 9.

Fig. 12 is a view for illustrating a cooling unit of the battery pack of fig. 2.

Fig. 13 is an exploded perspective view illustrating the cooling unit of fig. 12.

Fig. 14 is a sectional view illustrating the cooling unit of fig. 12.

Fig. 15 is a diagram for illustrating a side structural unit of the battery pack of fig. 2.

Fig. 16 is a diagram for illustrating a main board of the side structural unit of fig. 15.

Fig. 17 and 18 are diagrams for illustrating a coupling structure between the battery cells and the cooling unit by means of the side structural unit of fig. 15.

Fig. 19 and 20 are diagrams for illustrating an arrangement relationship of battery cells and cooling units by means of the side structural units of fig. 15.

Fig. 21 to 23 are diagrams for illustrating a contact structure of the battery cell of fig. 20 with a cooling unit.

Fig. 24 is a bottom view illustrating the side structural unit of fig. 15 when the side structural unit is coupled to the battery cell.

Fig. 25 is an enlarged bottom view showing a main portion of the side structural unit of fig. 24.

Fig. 26 is a side view showing a main portion of the side structural unit of fig. 24.

Fig. 27 to 29 are views for illustrating the formation of a battery case structure by injecting a filling member into the battery of fig. 2.

Fig. 30 is a diagram for illustrating a battery pack according to another embodiment of the present disclosure.

Fig. 31 is an exploded perspective view illustrating the battery pack of fig. 30.

Fig. 32 is a view for illustrating a bus bar assembly of the battery pack of fig. 30.

Fig. 33 is a view for illustrating a high voltage bus bar unit of the bus bar assembly of fig. 32.

Fig. 34 is a view for illustrating a side structural unit of the battery pack of fig. 30.

Fig. 35 is a diagram for illustrating a main board of the side structural unit of fig. 33.

Fig. 36 is a diagram for illustrating an arrangement relationship of battery cells and cooling units by means of the side structural units of fig. 34.

Fig. 37 to 40 are diagrams for illustrating mounting structures of the side structural unit and the high-voltage bus bar unit of fig. 34.

Fig. 41 and 42 are diagrams for illustrating injection of the filling member into the battery pack of fig. 30.

Fig. 43 is a diagram for illustrating a vehicle according to an embodiment of the present disclosure.

Detailed Description

The present disclosure will become more apparent by describing embodiments thereof in detail with reference to the accompanying drawings. It should be understood that the embodiments disclosed herein are illustrative only for a better understanding of the present disclosure, and that the present disclosure may be modified in various ways. Moreover, the drawings are not to scale, but the size of some of the components may be exaggerated for the purpose of facilitating an understanding of the present disclosure.

Fig. 1 is a diagram for illustrating a battery pack according to an embodiment of the present disclosure, and fig. 2 is an exploded perspective view illustrating the battery pack of fig. 1.

Referring to fig. 1 and 2, a battery pack 1 may be provided as an energy source to an electric vehicle or a hybrid electric vehicle. Hereinafter, the battery pack 1 provided to an electric vehicle or the like will be described in more detail with reference to the related drawings.

The battery pack 1 may include a plurality of battery cells 100, a bus bar assembly 200, a cooling unit 300, a side structural unit 400, and a filling member 500.

The plurality of battery cells 100 may be provided as secondary batteries such as cylindrical secondary batteries, pouch-type secondary batteries, or rectangular secondary batteries. Hereinafter, in the present embodiment, the plurality of battery cells 100 will be described as cylindrical secondary batteries.

Hereinafter, each of the battery cells 100 will be described in more detail with reference to the associated drawings.

Fig. 3 is a view for illustrating a battery cell of the battery pack of fig. 2, fig. 4 is a partial sectional view illustrating an internal structure of the battery cell of fig. 3, fig. 5 is a partial sectional view illustrating an upper structure of the battery cell of fig. 3, fig. 6 is a partial sectional view illustrating a lower structure of the battery cell of fig. 3, and fig. 7 is a bottom view illustrating the battery cell of fig. 3.

Referring to fig. 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-described components, the battery cell 100 may further include an insulating gasket 50 and/or an upper current collector plate 60 and/or an insulating plate 70 and/or a lower current collector plate 80 and/or a sealing gasket 90.

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 electrode plate and the second electrode plate. The first electrode plate is a positive electrode plate or a negative electrode plate, and the second electrode plate corresponds to an electrode plate having a polarity opposite to that of the first electrode plate.

The electrode assembly 10 may have, for example, a jelly roll shape. That is, the electrode assembly 10 may be manufactured by winding a stack formed by sequentially stacking a first electrode plate, a separator, and a second electrode plate at least once with respect to the winding center C. In this case, a separator may be provided on the outer circumferential surface of the electrode assembly 10 for insulation from the battery can 20.

The first electrode plate includes a first electrode current collector and a first electrode active material applied on one surface or both surfaces of the first electrode current collector. At one end of the first electrode current collector in the width direction (parallel to the Z-axis), there is an uncoated region to which the first electrode active material is not applied. The uncoated region served as the first electrode tab. The first electrode tab 11 is disposed at an upper portion of the electrode assembly 10 received in the battery can 20 in a height direction (parallel to the Z-axis).

The second electrode plate includes a second electrode current collector and a second electrode active material applied on one surface or both surfaces of the second electrode current collector. At the other end of the second electrode current collector in the width direction (parallel to the Z-axis), there is an uncoated region to which the second electrode active material is not applied. The uncoated region serves as the second electrode tab 12. The second electrode tab 12 is disposed at a lower portion of the electrode assembly 10 received in the battery can 20 in a height direction (parallel to the Z-axis).

The battery can 20 is a cylindrical container having an opening at the bottom, and is made of a metal material having conductivity. The side surfaces and the upper surface of the battery can 20 are integrally formed. The upper surface of the battery can 20 has an approximately flat shape. The battery can 20 accommodates the electrode assembly 10 through an opening formed at the bottom, and also accommodates an electrolyte together.

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.

The battery can 20 may include a beading portion 21 and a crimp portion 22 formed at a lower end of the beading portion 21. The beading part 21 is formed at the lower part of the electrode assembly 10. The beading portion 21 is formed by press-fitting the outer peripheral surface of the battery can 20. The beading part 21 prevents the electrode assembly 10 having a size corresponding to the width of the battery can 20 from being withdrawn through an opening formed at the bottom of the battery can 20, and may serve as a support for placing the cap plate 30.

The crimping portion 22 is formed below the hemming portion 21. The crimp portion 22 has an extended and bent shape so as to surround portions of the outer peripheral surface of the cap plate 30 and the lower surface of the cap plate 30 disposed under the crimp portion 21.

The cap plate 30 is a member made of a metal material having conductivity, and covers an opening formed at the bottom of the battery can 20. That is, the cap plate 30 forms the lower surface of the battery cell 100. The cap plate 30 is placed on the beading portion 21 formed at the battery can 20, and is fixed by the crimping portion 22. An airtight gasket 90 may be interposed between the cap plate 30 and the crimp 22 of the battery can 20 to ensure the airtight of the battery can 20.

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 exhaust portion 31 corresponds to a region having a thinner thickness than the surrounding region of the cover plate 30. The exhaust portion 31 is structurally weaker than the surrounding area. Therefore, when an abnormality occurs in which the internal pressure increases to a level or more in the battery cell 100, the vent 31 breaks, so that the gas generated inside the battery can 20 is discharged.

The hole on the upper surface of the battery can 20 may be preformed before the first electrode terminal 40 and the insulating gasket 50 are placed, but this is not required. For example, holes may be formed at the time of inserting the first electrode terminal 40, or holes having different diameters may be formed in advance, or the upper surface may be notched or pre-notched, and the insertion of the first electrode terminal 40 may expand the holes to a desired size, or pierce the notches to form small holes, and then expand the small holes to a desired size. Other methods of forming the holes may be used.

The battery cell 100 according to the embodiment of the present disclosure has a structure in which both the positive terminal and the negative terminal are present at the upper portion thereof, and thus the upper structure is more complex than the lower structure. Accordingly, the gas discharge part 31 may be formed at the cap plate 30 forming the lower surface of the battery cell 100 so as to smoothly discharge the gas generated in the battery can 20.

The exhaust portion 31 may be continuously formed in a circular shape on the cover plate 30. The present invention is not limited thereto, and the exhaust portion 31 may be discontinuously formed in a circular shape on the cover plate 30, or may be formed in a linear shape or other shapes.

The first electrode terminal 40 is made of a metal material having conductivity, and passes through the upper surface of the battery can 20 to be electrically connected to the first electrode tab 11 of the electrode assembly 10. Accordingly, the first electrode terminal 40 has a first polarity. The first electrode terminal 40 is electrically insulated from the battery can 20 having the second polarity.

The first electrode terminal 40 includes an exposed terminal portion 41 and an inserted 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 is electrically connected to the first electrode tab 11 through a central portion of the upper surface of the battery can 20. The insertion terminal portion 42 may be riveted to the inner surface of the battery can 20.

The upper surface of the battery can 20 and the first electrode terminal 40 have opposite polarities and face in the same direction. Further, 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 the upper surface of the battery can 20 has a shape protruding upward from the center thereof, the exposed terminal portion 41 of the first electrode terminal 40 may further protrude upward to the upper surface of the battery can 20. In contrast, when the upper surface of the battery can 20 has a concave shape concavely from the center downward, i.e., toward the electrode assembly 10, the upper surface of the battery can 20 may further protrude upward to the exposed terminal portion 41 of the first electrode terminal 40.

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 having opposite polarities from contacting each other. Accordingly, the upper surface of the battery can 20 having an approximately flat shape may serve as the second electrode terminal of the battery cell 100.

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

In the case where the insulating gasket 50 is made of a resin material, the insulating gasket 50 may be coupled with the battery can 20 and the first electrode terminal 40 by, for example, thermal fusion. In this case, the air tightness at the coupling interface between the insulating gasket 50 and the first electrode terminal 40 and at the coupling interface between the insulating gasket 50 and the battery can 20 may be reinforced.

In the upper surface of the battery can 20, the entire area except for the area occupied by the first electrode terminal 40 and the insulating gasket 50 corresponds to the second electrode terminal 20a having the polarity opposite to that of the first electrode terminal 40.

The battery cell 100 according to the embodiment of the present disclosure 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, which are commonly located at one side thereof in a longitudinal direction (parallel to a Z-axis). That is, in the battery cell 100 according to the embodiment of the present disclosure, since the pair of electrode terminals 40, 20a are positioned along the same direction, in the case of electrically connecting a plurality of battery cells 100, an electrical connection part (described later) such as the bus bar assembly 200 may be provided at only one side of the battery cell 100. This may lead to a simplification of the structure of the battery pack 1 and an improvement in energy density.

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

Referring again to fig. 2, the bus bar assembly 200 may be disposed at one side of the battery cells 100, specifically, at an upper side (+z-axis direction) of the battery cells 100, and may be electrically connected to a plurality of battery cells 100. The electrical connection of the busbar assembly 200 may be parallel and/or series.

The bus bar assembly 200 is electrically connected to the first electrode terminals 40 (see fig. 3) of the plurality of battery cells 100 having the first polarity and the second electrode terminals 20a (see fig. 3) of the battery can 20 (see fig. 3) having the second polarity, and may be electrically connected to an external charging/discharging line or the like through the connector terminal 290 or the like. Here, the first polarity may be a positive polarity, and the second polarity may be a negative polarity.

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

Fig. 8 is a view for illustrating a bus bar assembly of the battery pack of fig. 2, fig. 9 is a view for illustrating a connection bus bar unit of the bus bar assembly of fig. 8, fig. 10 is an exploded perspective view illustrating the connection bus bar unit of fig. 9, and fig. 11 is an enlarged view for illustrating a main portion of the connection bus bar unit of fig. 9,

referring to fig. 8 to 11 and 2, the bus bar assembly 200 may include a main bus bar unit 210, a connection bus bar unit 230, an interconnection plate 260, and a connector terminal 290.

The main bus bar unit 210 may be provided in plurality, and may be electrically connected to the battery cells 100 disposed at the outermost sides in the longitudinal direction (Y-axis direction) of the battery pack 1. The main bus bar unit 210 may be electrically connected to a connector terminal 290 (described later).

The connection bus bar units 230 may be disposed between the main bus bar units 210 in the longitudinal direction (Y-axis direction) of the battery pack 1, may be electrically connected to the plurality of battery cells 100, and may cover the plurality of battery cells 100.

The connection bus bar unit 230 may be provided in a single number having a size capable of covering all of the plurality of battery cells 100, or may be provided in a plurality to cover the plurality of battery cells 100. Hereinafter, in the present embodiment, the connection bus bar unit 230 is provided in plurality will be described.

Each of the plurality of connection bus bar units 230 may include a bus bar cover 240 and a sub bus bar 250.

The bus bar cover 240 covers the upper sides of the plurality of battery cells 100 and may be provided in an approximately flat plate shape. The shape and size of the bus bar cover 240 may vary according to the number or capacity of the battery cells 100 required in the battery pack 1.

The bus bar cover 240 may be made of an insulating material. For example, the bus bar cover 240 may be made of a polyimide film. The present invention is not limited thereto, and the bus bar cover 240 may be provided as other insulating members made of an insulating material.

The bus bar covers 240 may be provided in a pair to have shapes and sizes corresponding to each other in the up-down direction (Z-axis direction) of the battery pack 1, and the pair of bus bar covers 240 may be coupled to each other. Here, a sub bus bar 250 (described later) may be interposed between the pair of bus bar covers 240.

The bus bar cover 240 may include a positive bus bar hole 242, a negative bus bar hole 244, and a guide hole 246.

The positive electrode bus bar hole 242 has an open space of a predetermined size and may be provided in plurality. A positive electrode connection portion 254 (described later) may be exposed in the positive electrode bus bar hole 242. Here, the positive electrode bus bar hole 242 may be formed to have an open space larger than a size of the positive electrode connection portion 254 (described later) in order to improve process operability and improve efficiency of injecting the filling member 500 (described later).

The positive electrode bus bar hole 242 may more effectively guide the electrical connection between the positive electrode connection portion 254 (described later) and the first electrode terminal 40 (see fig. 3) that is the positive electrode of the battery cell 100.

Further, through the open space of the positive electrode bus bar hole 242, when the filling member 500 (described later) is injected, the injection efficiency of the filling member 500 can be significantly improved. Specifically, the filling member 500 (described later) provided as the potting resin 500 may be more directly injected from the upper side of the battery pack 1 to the lower side thereof in the vertical direction (Z-axis direction) through the open space of the positive electrode bus bar hole 242, and thus the injection efficiency between the battery cells 100 may be significantly improved.

The negative electrode bus bar hole 244 is provided to face the positive electrode bus bar hole 242, has an open space of a predetermined size similar to the positive electrode bus bar hole 242, and may be provided in plurality. Here, the anode bus bar hole 244 may be formed to have an open space larger than a size of an anode connection portion 256 (described later) in order to improve process operability and improve injection efficiency of the filling member 500 (described later).

The negative electrode bus bar hole 244 may more effectively guide the electrical connection between a negative electrode connection portion 256 (described later) and the battery can 20 (see fig. 3), specifically, the second electrode terminal 20a serving as the negative electrode of the battery cell 100.

Further, through the open space of the anode bus bar hole 244, when the filling member 500 (described later) is injected, the injection efficiency of the filling member 500 can be significantly increased. In particular, since the filling member 500 (described later) provided as the potting resin 500 may be more directly injected through the open space of the negative electrode bus bar hole 244 from the upper side of the battery pack 1 to the lower side thereof in the vertical direction (Z-axis direction), the injection efficiency between the battery cells 100 may be significantly improved.

The guide hole 246 may guide an assembly position of the bus bar assembly 200. Specifically, the guide holes 246 may fix the connection bus bar unit 230 to the side structural unit 400 to guide the proper arrangement of the connection bus bar unit 230.

The guide hole 246 may be provided in plurality. The bus bar guide protrusions 416 of the side structural units 400 (described later) may be inserted into the plurality of guide holes 246.

The sub-bus bars 250 are used to be electrically connected with the first electrode terminal 40 serving as the positive electrode and the second electrode terminal 20a serving as the negative electrode of the plurality of battery cells 100, and are disposed on the upper sides of the bus bar covers 240 or inserted into the pair of bus bar covers 240. Hereinafter, in the present embodiment, the insertion or coupling of the sub-bus bar 250 into the bus bar cover 240 will be described.

The sub bus bar 250 may include a bus bar bridge 252, a positive electrode connection 254, and a negative electrode connection 256.

The bus bar bridge 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 1. The bus bar bridge 252 may be provided to have a shape corresponding to the arrangement structure of the battery cells 100 in the width direction (X-axis direction) of the battery pack 1 to improve the efficiency of the electrical connection with the battery cells 100. Therefore, in the present embodiment, the bus bar bridges 252 may be arranged in a zigzag manner along the width direction (X-axis direction) of the battery pack 1.

The bus bar bridge 252 may be provided in plurality. A plurality of bus bar bridges 252 may be inserted into the bus bar cover 240 and disposed to be spaced apart from each other by a predetermined distance in the longitudinal direction (Y-axis direction) of the battery pack 1.

The bus bar bridge 252 may be made of a conductive material. For example, the bus bar bridge 252 may be made of aluminum or copper as a metal material. The present disclosure is not limited thereto, and of course the bus bar bridge 252 may be made of other materials for electrical connection.

The positive electrode connection portion 254 integrally extends from and protrudes from the bus bar bridge 252, and may be disposed in the positive electrode bus bar hole 242. The positive electrode connection portion 254 may be electrically connected to the first electrode terminal 40 (see fig. 3) serving as a positive electrode of the battery cell 100. The electrical connection may be performed by a soldering process (e.g., laser soldering or ultrasonic soldering) for the electrical connection.

Since the positive electrode connection portion 254 and the positive electrode (first electrode terminal) 40 of the battery cell 100 are connected in the open space of the positive electrode bus bar hole 242, a welding process for connection can be directly performed in the open space during the connection without any other process.

The negative electrode connection portion 256 may integrally extend from the bus bar bridge 252 to protrude in a direction opposite to the positive electrode connection portion 254, and may be disposed in the negative electrode bus bar hole 244. The negative electrode connection part 256 may be electrically connected to the second electrode terminal 20a (see fig. 3) serving as a negative electrode of the battery cell 100. The electrical connection may be performed by a soldering process (e.g., laser soldering or ultrasonic soldering) for the electrical connection.

Since the negative electrode connection part 256 and the negative electrode (second electrode terminal) 20a of the battery cell 100 are connected in the open space of the negative electrode bus bar hole 244, a welding process for connection can be directly performed in the open space without any other process.

The interconnection plate 260 is connected to an external sensing line, and may be disposed at one end (-Y axis direction) of the battery pack 1. The arrangement position of the interconnection plate 260 may vary according to design or the like, and the interconnection plate 260 may be disposed at other positions that can be connected with external sensing lines. Further, the interconnection plates 260 may be provided in plurality according to the number or capacity of the battery cells 100 of the battery pack 1.

The interconnection plate 260 may be disposed to be exposed to the outside of the battery pack 1 to be connected with an external sensing line. External sense lines may connect interconnect board 260 and a battery management system (not shown). The battery management system may determine a state of charge of the parallel-connected battery cells based on the voltages of the parallel-connected battery cells.

Interconnect board 260 may include a thermistor for checking the temperature status of battery cell 100. The thermistor may be included in the interconnect board 260 or may be separately mounted outside the interconnect board 260. The connector terminals 290 may be provided in pairs. The pair of connector terminals 290 are for connection with external charge/discharge lines, and may be provided as high-voltage connector terminals.

Referring again to fig. 2, the cooling unit 300 serves to cool the battery cells 100, and is disposed at the lower side (-Z-axis direction) of the bus bar assembly 200, and may be disposed between the plurality of battery cells 100 along the longitudinal direction (Y-axis direction) of the battery pack 1.

The cooling unit 300 may be provided in plurality.

The plurality of cooling units 300 may be disposed to face the plurality of battery cells 100 in the width direction (X-axis direction) of the battery pack 1. Here, a plurality of cooling units 300 may be disposed to contact the battery cells 100 facing each other to improve cooling performance.

Hereinafter, the cooling unit 300 will be described in more detail.

Fig. 12 is a view for illustrating a cooling unit of the battery pack of fig. 2, fig. 13 is an exploded perspective view illustrating the cooling unit of fig. 12, and fig. 14 is a sectional view illustrating the cooling unit of fig. 12.

Referring to fig. 12 to 14 and 2, the cooling unit 300 may include a cooling pipe 310, a cooling passage 350, and a cooling fluid inlet/outlet portion 370.

The cooling pipe 310 is formed to have a predetermined length along the longitudinal direction (Y-axis direction) of the battery pack 1, is disposed between the plurality of battery cells 100, and may have a cooling passage 350 (described later) for circulation of a cooling fluid. In an embodiment, the cooling fluid may be water, and reference to the cooling fluid is not limited to water, but includes one or more fluids that are also capable of exchanging heat with the surrounding environment.

The cooling pipe 310 may be formed to have a shape corresponding to the outer surfaces of the plurality of battery cells 100 facing each other in the width direction (X-axis direction) of the battery pack 1.

The cooling pipe 310 has a plurality of convex portions 312 and concave portions 316 that are convex and concave in the width direction (X-axis direction) of the battery pack 1 to be alternately arranged along the longitudinal direction (Y-axis direction) of the battery pack 1.

The cooling tube 310 may be disposed in contact with the outer surfaces of the plurality of battery cells 100 to further increase the cooling performance of the battery cells 100. The cooling tube 310 may be adhesively fixed to the plurality of battery cells 100 by a filling member 500 (described later) or a separate adhesive member.

At one end (-Y-axis direction) of the cooling tube 310, a cooling fluid guide 318 (described later) for guiding the cooling fluid into the cooling passage 350 may be provided. The cooling fluid guide portions 318 are formed at one end (-Y-axis direction) of the cooling tube 310 in the longitudinal direction (Y-axis direction), and may be provided in pairs. Any one of the pair of cooling fluid guides 318 may communicate with an upper channel 352 (described later) of the cooling channel 350, and the other of the pair of cooling fluid guides 318 may communicate with a lower channel 354 (described later) of the cooling channel 350. Specifically, any one of a pair of cooling fluid guides 318 may be provided on an upper side (+z-axis direction) of the cooling tube 310 in a height direction (Z-axis direction) to communicate with an upper passage 352 (described later), and the other of the pair of cooling fluid guides 318 may be provided on a lower side (-Z-axis direction) of the cooling tube 310 in the height direction (Z-axis direction) to communicate with a lower passage 354 (described later).

The cooling passage 350 circulates a cooling fluid for cooling the battery cell 100, is provided in the cooling pipe 310, and may be connected in communication with a cooling fluid inlet/outlet portion 370 (described later).

The cooling channel 350 may include an upper channel 352, a lower channel 354, and a connecting channel 356.

The upper channel 352 is provided at an upper side of the cooling tube 310 to be provided close to the bus bar assembly 200, and may be formed to have a predetermined length along a longitudinal direction (Y-axis direction) of the cooling tube 310. The upper passage 352 may be communicatively connected with the cooling fluid supply port 374 of the cooling fluid inlet/outlet portion 370.

One upper channel 352 or a plurality of upper channels 352 may be provided. Hereinafter, in the present embodiment, in order to secure cooling performance, it will be described that the upper channels 352 are provided in plural.

The lower channel 354 is disposed at a lower side (-Z axis direction) of the cooling tube 310 to be spaced apart from the at least one upper channel 352, and may be formed to have a predetermined length along a longitudinal direction (Y axis direction) of the cooling tube 310. The lower passage 354 may be communicatively connected with a cooling fluid discharge port 376 of the cooling fluid inlet/outlet portion 370.

A lower channel 354 or a plurality of lower channels 354 may be provided. Hereinafter, in the present embodiment, in order to secure cooling performance, it will be described that the lower passages 354 are provided in plurality.

In this embodiment, the connection channel 356 may connect at least one upper channel or a plurality of upper channels 352, and in this embodiment, the connection channel 356 may connect at least one lower channel or a plurality of lower channels 354.

The connection passage 356 may be provided at the other end (+y-axis direction) of the cooling tube 310 opposite to the cooling fluid inlet/outlet portion 370 so as to fix the cooling passage 350 as much as possible.

In the present embodiment, when the cooling fluid of the cooling passage 350 circulates, the cooling fluid supplied from the cooling fluid supply port 374 is preferentially supplied to the upper passage 352 provided near the bus bar assembly 200, and then may flow to the cooling fluid discharge port 376 via the connection passage 356 and the lower passage 354.

Therefore, in the present embodiment, since the cold cooling fluid is preferentially supplied to the region having the relatively high temperature distribution near the bus bar assembly 200, the cooling performance of the battery cell 100 will be significantly improved within the battery pack 1.

The cooling fluid inlet/outlet portion 370 may be connected to the cooling tube 310 to communicate with the cooling channel 350 of the cooling tube 310. The cooling fluid inlet/outlet portion 370 may be exposed to the outside of the side structural unit 400 (described later) and connected in communication with an external cooling line.

The cooling fluid inlet/outlet portion 370 may be provided at one side (-Y-axis direction) of the side surface of the battery pack 1 along the longitudinal direction (Y-axis direction). The cooling pipe 310 connected to the cooling fluid inlet/outlet portion 370 may be formed to have a predetermined length along the longitudinal direction (Y-axis direction) of the battery pack 1 from the cooling fluid inlet/outlet portion 370 toward the other side (+y-axis direction) of the side surface of the battery pack 1.

The cooling fluid inlet/outlet portion 370 may include an inlet/outlet portion body 370a, a cooling fluid supply port 374, and a cooling fluid discharge port 376.

The inlet/outlet body 370a may be connected to one end (-Y-axis direction) of the cooling tube 310. The inlet/outlet body 370a may include a supply port body 371 and a discharge port body 372.

The supply port body 371 covers one end (-Y axis direction) of the cooling tube 310, and may be coupled to a discharge port body 372 (described later). In the supply port body 371, a supply port via 371a may be formed through which a cooling fluid supply port 374 (described later) passes. A cooling fluid supply port 374 (described later) may pass through the supply port via 371a and communicate with the upper channel 352 (described later) through the cooling fluid guide 318. Specifically, the cooling fluid supply port 374 (described later) may communicate with an upper passage 352 (described later) located on the upper side (+z-axis direction) of the cooling fluid guide 318 of the cooling pipe 310 through the cooling fluid guide 318.

The discharge port body 372 may be coupled with the supply port body 371 at a side opposite to the supply port body 371, with one end (-Y axis direction) of the cooling tube 310 interposed between the discharge port body 372 and the supply port body 371 to cover one end (-Y axis direction) of the cooling tube 310. Here, the discharge port body 372 and the supply port body 371 may be assembled to each other by press-fitting (press-fitting).

In the discharge port body 372, a discharge port via 372a may be formed, and a cooling fluid discharge port 376 (described later) passes through the discharge port via 372a. A cooling fluid discharge port 376 (described later) may pass through the discharge port via 372a and communicate with the lower channel 354 (described later) through the cooling fluid guide 318. Specifically, a cooling fluid discharge port 376 (described later) may communicate with a lower passage 354 (described later) located on the lower side (-Z-axis direction) of the cooling fluid guide 318 of the cooling pipe 310 through the cooling fluid guide 318.

The cooling fluid supply port 374 is provided to the supply port body 371 of the inlet/outlet body 370a, and may be communicatively connected with the upper channel 352. Here, the cooling fluid supply port 374 may be coupled to the supply port body 371 through caulking (molding). The cooling fluid supply port 374 may be connected in communication with an external cooling line.

A cooling fluid discharge port 376 is provided to the discharge port body 372 of the inlet/outlet body 370a and may be communicatively connected to the lower passage 374. Here, the cooling fluid discharge port 376 may be coupled with the discharge port body 372 through caulking. The cooling fluid discharge port 376 is disposed a predetermined distance from the cooling fluid supply port 374 and may be communicatively connected to an external cooling line.

Referring again to fig. 2, the side structural unit 400 may be made of a plastic resin material, support the battery cells 100, secure rigidity of the battery cells 100, and form a side appearance of the battery pack 1.

Hereinafter, the side structural unit 400 will be described in more detail with reference to the related drawings.

Fig. 15 is a diagram for illustrating a side structural unit of the battery pack of fig. 2, and fig. 16 is a diagram for illustrating a main board of the side structural unit of fig. 15.

Referring to fig. 15 and 16, the side structure unit 400 may support the battery cells 100, secure rigidity of the battery cells 100, and form the outside of the side surface of the battery pack 1 (see fig. 2) to serve as a battery pack case forming the external appearance of the battery pack 1 (see fig. 2).

The side structural unit 400 is formed to have a predetermined length along the longitudinal direction (Y-axis direction) of the battery pack 1, and can accommodate and support the battery cells 100.

The side structural unit 400 may include a main board 410 and an end board 450.

The main board 410 is formed to have a predetermined length along the longitudinal direction (Y-axis direction) of the battery pack 1, and may house the battery cells 100 to be arranged in two rows in the width direction (X-axis direction) of the battery pack 1. The main plate 410 is provided in plurality, and the plurality of main plates 410 may be arranged to be spaced apart from each other by a predetermined distance in the width direction (X-axis direction) of the battery pack 1.

The plurality of main boards 410 may ensure rigidity of the battery cells 100 and the cooling unit 300 and occupy a predetermined space in the battery pack 1 (see fig. 2) to reduce an injection amount of the filling member 500 (described later). The filling member 500 (described later) made of silicone has a relatively high cost, and thus it is possible to further secure the cost competitiveness of the manufacturing of the battery pack 1 by reducing the injection amount of silicone by means of the plurality of main plates 410.

Each of the plurality of main boards 410 may include a first cell receiving part 411, a second cell receiving part 412, a middle wing 413, a bottom rib 415, a bus bar guide protrusion 416, a cooling unit insertion groove 417, and a guide protrusion 418.

The first battery cell receiving part 411 may be disposed at the front side (+x-axis direction) of the main board 410 along the longitudinal direction (Y-axis direction) of the main board 410. The first cell housing 411 may house a plurality of battery cells 100 disposed along the longitudinal direction (Y-axis direction) of the battery pack 1. For this, the first cell receiving part 411 may be provided in plurality at the front side (+x axis direction) of the main board 410.

Each of the plurality of first cell containers 411 is provided to have a concave shape corresponding to the outer surface of the battery cell 100, and may at least partially surround the outer surface of the battery cell 100.

The second battery cell receiving part 412 may be disposed at the rear side (-X-axis direction) of the main board 410 along the longitudinal direction (Y-axis direction) of the main board 410. The second cell receiving part 412 may receive a plurality of battery cells 100 disposed along the longitudinal direction (Y-axis direction) of the battery pack 1. For this, the second cell receiving part 412 may be provided in plurality at the rear side (-X-axis direction) of the main board 410.

Each of the plurality of second cell containers 412 is provided to have a concave shape corresponding to the outer surface of the battery cell 100, and may at least partially surround the outer surface of the battery cell 100.

The plurality of second battery cell receiving parts 412 may be alternately arranged with the plurality of first receiving parts 411 in the front-rear direction (X-axis direction) of the main board 410 to receive the battery cells 100 provided as the cylindrical secondary batteries as much as possible.

The middle wing 413 is provided in plurality, and the plurality of middle wings 413 may be formed to protrude in the width direction (X-axis direction) of the main plate 410 to separate the plurality of first and second receiving parts 411 and 412 from each other. Specifically, a plurality of middle wings 413 may be formed at both the front side (+x-axis direction) and the rear side (-X-axis direction) of the main plate 410 along the width direction (X-axis direction). More specifically, among the plurality of middle wings 413, the middle wing 413 protruding at the front side (+x-axis direction) of the main board 410 may partition the plurality of first cell housing parts 411, and among the plurality of middle wings 413, the middle wing 413 protruding at the rear side (-X-axis direction) of the main board 410 may partition the plurality of second cell housing parts 412.

The bottom rib 415 is disposed at the bottom of the main board 410, and the bottom rib 415 may support the bottom of the battery cell 100 when the battery cell 100 is received in the main board 410.

When the battery cell 100 is accommodated in the main board 410, the bottom rib 415 may be formed to further protrude to the bottom of the battery cell 100 in a downward direction (-Z-axis direction).

The bus bar guide protrusion 416 is used to fixedly connect the bus bar unit 230 and is provided to the upper surface of the main board 410 when the bus bar assembly 200 is assembled, and one bus bar guide protrusion 416 or a plurality of bus bar guide protrusions 416 may be provided. Hereinafter, in the present embodiment, it will be described that the bus bar guide protrusion 416 is provided in plurality.

When the bus bar assembly 200 is assembled, the plurality of bus bar guide protrusions 416 may be inserted into the guide holes 246 of the bus bar cover 240 to guide the proper positioning of the connection bus bar unit 230. Since the connection bus bar unit 230 is inserted and fixed or coupled into the plurality of bus bar guide protrusions 416, a welding process or the like for electrical connection of the bus bar assembly 200 may be more stably performed, and welding quality may be further improved during the welding process.

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

The guide protrusions 418 may be provided to protrude to a predetermined height at both upper ends along the longitudinal direction (Y-axis direction) of the main plate 410. When the side structural unit 400 is completely assembled by coupling the main plate 410 and the end plate 450 (described later), the guide protrusion 418 may form an edge of the side structural unit 400 together with the end guide protrusion 458 of the end plate 450 (described later).

The end plates 450 are provided in pairs, and the pair of end plates 450 may be provided at both outermost sides in the width direction (X-axis direction) of the side structural unit 400. A pair of end plates 450 disposed at opposite sides may receive and support the battery cells 100 together with the main plate 410.

The pair of end plates 450 may have terminal holes 456 and end guide protrusions 458.

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

The end guide protrusion 458 is formed along the upper edge of the end plate 450 and may be provided to protrude at the same height as the guide protrusion 418. When the side structural unit 400 is fully assembled, the end guide protrusions 458 may form edges of the side structural unit 400 together with the guide protrusions 418 of the main plate 410.

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

Referring to fig. 17 and 18, first, the cooling pipe 310 of the cooling unit 300 may be inserted between the battery cells 100 arranged in the front and rear two rows in the width direction (X-axis direction) of the battery pack 1 (see fig. 2) among the battery cells 100. The side structural unit 400 may accommodate the battery cells 100 facing each other in the front-rear direction (X-axis direction) of the battery cells 100 with the cooling tube 310 interposed therebetween.

Specifically, in the width direction (X-axis direction) of the battery pack 1 (see fig. 2), the end plates 450, the battery cells 100, the cooling pipes 310, the battery cells 100, and the main plate 410, which are disposed at the outermost sides, are arranged, and then the battery cells 100, the cooling pipes 310, the battery cells 100, and the main plate 410 may be sequentially arranged and coupled. Thereafter, in the width direction (X-axis direction) of the battery pack 1 (see fig. 2), the end plates 450 disposed at the opposite outermost sides may be finally disposed and coupled to complete the coupling of the side structural units 400, so that the battery cells 100 and the cooling units 300 may be accommodated in the side structural units 400.

Here, both ends of the cooling unit 300 may be inserted into the cooling unit insertion groove 417 when the main plate 410 is coupled and the main plate 410 and the end plate 450 are coupled, thereby preventing interference with the cooling unit 300 while more stably fixing the cooling unit 300.

Further, a cooling fluid inlet/outlet portion 370 provided at one end of the cooling unit 300 may be provided to protrude out of the side structural unit 400 to be connected with an external cooling line or the like.

The side structure unit 400 according to the present embodiment may form a side outer structure of the battery pack 1 (see fig. 2) by coupling the main plate 410 and the end plate 450 to each other while accommodating the battery cells 100 and the cooling unit 300. That is, the side structural unit 400 may serve as a battery pack case forming the external appearance of the battery pack 1.

Therefore, the battery pack 1 (see fig. 1) according to the present embodiment may omit a separate additional battery pack case or battery pack case structure by means of the side structural unit 400, thereby reducing manufacturing costs and reducing the overall size of the battery pack 1 while further improving energy density.

Referring to fig. 19 and 20, a distance a between centers of the battery cells 100 disposed between the first and second cell receiving parts 411 and 412 of the main board 410 is a distance disposed to be in close contact with the main board 410, and the distance a may vary according to the thickness of the main board 410.

Further, the distance B between centers of adjacent battery cells 100 in contact with one surface of the cooling tube 310 is a distance provided so that the contact angle of the battery cells 100 and the cooling tube 310 is a predetermined angle (for example, 60 degrees), and may vary in conjunction with the distance C (described later). The distance C between the centers of the battery cells 100 disposed to face each other with the cooling tube 310 interposed therebetween is a distance reflecting the thickness of the cooling tube 310, and may be determined in combination with the distance B between the centers of the neighboring battery cells 100 in contact with one side of the cooling tube 310.

The distances a to C may be set to an optimal distance for closer adhesion between the battery cells 100, the cooling pipes 310, and the side structural units 400. Specifically, the optimal distance may be determined in consideration of the diameter of the battery cell 100, the thickness of the cooling tube 310, the contact angle (θ) between the battery cell 100 and the cooling tube 310, and the like. For example, in the present embodiment, the diameter of the battery cell 100 may be set to 46mm, and the thickness of the cooling tube 310 may be set to 2.5mm.

Further, the optimal distance may represent a distance when the contact angle (θ) between the battery cell 100 and the cooling tube 310 is 60 ° or about 60 °. Here, the interval (P1) between the contact parts of the cooling pipes 310 may be associated with the interval of the battery cells 100, and in the present embodiment, the interval (P1) may be set to 49mm.

The distance (d 1) between the battery cells 100 placed facing each other across the cooling tube 310 in the diagonal direction may be determined in combination with the assembly characteristics between the battery cells 100 and the cooling tube 310, the thickness of a coating agent or glue for adhesion between the battery cells 100, and the like. For example, the distance (d 1) may be prepared considering both the thickness of the cooling tube 310 and the thickness of the coating agent or glue coated on both sides of the cooling tube 310. Specifically, when the thickness of the cooling tube 310 is 2.5mm, the thickness of the coating agent (e.g., epoxy coating agent) is 0.25mm at maximum, and the thickness of the paste is 0.1mm, the distance (d 1) may be prepared considering the thickness of the cooling tube 310 (2.5 mm) and all of the thickness of the coating agent (2×0.25 mm) and the thickness of the paste (2×0.1 mm) applied to both sides of the cooling tube 310.

In addition, the end of the middle wing 413 disposed between the first and second battery cell receiving parts 411 and 412 of the main plate 410 may be formed to be shorter than one surface of the battery cell 100 in contact with the cooling tube 310 in order to prevent interference with the cooling tube 310 facing the main plate 410.

For example, considering the diameter of the battery cell 100, the thickness of the cooling tube 310, and the like, the distance (P2) between the end of the middle wing 413 of the main plate 410 and the center of the battery cell 100 may be prepared as a distance capable of avoiding interference with the cooling tube 310. For example, the distance (P2) between the end of the middle wing 413 and the center of the battery cell 100 may be set to 15mm.

In addition, the thicknesses of the first and second battery cell receiving parts 411 and 412 of the main board 410 may be prepared in consideration of the assembly characteristics of the battery cell 100.

Specifically, the thicknesses of the first and second cell receiving parts 411 and 412 of the main board 410 may be prepared in consideration of the distance (d 2) between the battery cells 100, and the minimum thickness (t) of the first and second cell receiving parts 411 and 412 may be about half of the distance (d 2) between the battery cells 100. For example, in the present embodiment, the distance (d 2) between the battery cells 100 may be set to 1.5mm, and the minimum thickness (t) of the first and second cell housing parts 411 and 412 may be set to about 0.75mm, particularly 0.7mm.

Accordingly, when the battery cells 100 are received in the first and second cell receiving parts 411 and 412 of the main board 410, a predetermined gap space g may be formed at the first and second cell receiving parts 411 and 412.

When the battery cells 100 are respectively received in the cell receiving parts 411, 412, the gap space g may be formed in the remaining region except for the innermost partial region of the concave shape of the first and second cell receiving parts 411, 412. Here, the innermost partial region of the concave shape of the first and second cell housing parts 411 and 412 may refer to a region disposed opposite to the protruding part of the middle wing 413 on the inner surface of the concave shape of the first and second cell housing parts 411 and 412.

Therefore, when the battery cell 100 is received in the first and second cell receiving parts 411 and 412 of the main board 410, the battery cell 100 is in contact with the inner surfaces of the first and second cell receiving parts 411 and 412 only in the innermost partial region of the concave shape, and may be spaced apart by the gap space g in the inner surfaces of the first and second cell receiving parts 411 and 412 except for the innermost partial region of the concave shape. Further, the innermost partial region of the concave shape contacting the battery cell 100 may be coated with an adhesive bonded to the battery cell 100.

In addition, when the battery cells 100 are received in the first and second cell receiving parts 411 and 412 of the main board 410, the middle wing 413 may also be disposed to be spaced apart from the battery cells 100 by a gap space g.

In the present embodiment, through the gap space g as described above, when the battery cell 100 and the main board 410 are assembled, particularly when the battery cell 100 is accommodated in the first cell accommodation portion 411 and the second cell accommodation portion 412, the assembling performance can be significantly improved by preventing the battery cell 100 from interfering with or colliding with the first cell accommodation portion 411, the second cell accommodation portion 412, the middle wing 413, and the like.

Further, in the present embodiment, the assembly tolerance of the components can be absorbed to a large extent by the clearance space g, and thus problems such as erroneous assembly or assembly defects caused by the assembly tolerance or the like can also be significantly reduced.

Further, the gap space g may be filled with a filling member 500 (described later). Since the filling member 500 is filled in the gap space g as described above in the present embodiment, the filling amount of the filling member 500 between the battery cells 100 can be further ensured.

Therefore, in the present embodiment, by filling the filling member 500 in the gap space g, the battery cell 100 can be more stably supported in the first cell housing 411 and the second cell housing 412 of the main board 410.

Further, by filling the filling member 500 in the gap space g, when an event such as thermal runaway occurs at the battery cell 100, electrical connection to the neighboring battery cell 100 or thermal runaway can be more effectively prevented.

Referring to fig. 21 to 23, the outer surface of the battery cell 100 may be in contact with the cooling tube 310 of the cooling unit 300 in the height direction (Z-axis direction). Here, the contact area (A2) between the battery cell 100 and the cooling tube 310 may be determined according to the contact angle (θ) between the battery cell 100 and the cooling tube 310, the height (h 2) of the cooling tube 310, and the like, in consideration of assembly characteristics, optimal cooling performance, and the like.

In the present embodiment, the contact area (A2) between the cooling pipes 310 of the battery cell 100 may be in the range of about 14% to 15% of the total area (A1) of the outer surface of the battery cell 100.

For example, in the present embodiment, the radius (R) of the battery cell 100 may be 23mm, the height (h 1) may be 80mm, the height (h 2) of the cooling tube 310 may be 70mm, and the contact angle (θ) between the battery cell 100 and the cooling tube 310 may be 60 °. In this case, the total area (A1) of the outer surface of the battery cell 100 may be determined as the product of the circumferential length (2rr) (i.e., the base length (2rr)) and the outside height (h 1) of the battery cell 100. Thus, the total area (A1) of the outer surface of the battery cell 100 may be 0.368 pi m ² And when pi is replaced by 3.14, the total area (A1) may be about 1.16m ² . Further, the contact area (A2) between the cooling pipes 310 of the battery cell 100 may be determined as a product of the arc length (l) depending on the contact angle (θ) and the height (h 2) of the cooling pipe 310. Here, the arc length (l) can be derived using the following equation.

[ equation 1]

Thus, the arc length (l) may be about 0.077pi m, and if replaced by 3.14, it may be about 0.242m. Thus, by multiplying the arc length (l) by 70mm, which is the height (h 2) of the cooling tubes 310, the contact area (A2) between the cooling tubes 310 of the battery cell 100 may be about 0.169m ² 。

As described above, in the present embodiment, the contact area (A2) between the cooling pipes 310 of the battery cell 100 may be set within the range of about 14.5% of the total area (A1) of the outer surface of the battery cell 100 to ensure optimal cooling performance and assembly characteristics with the cooling pipes 310.

In an embodiment, the height (h 1) of the battery cell 100 is greater than the height (h 2) of the cooling tube 310 to avoid contact between the cooling tube 310 and the connection bus bar unit 230, thereby preventing the possibility of a short circuit between the cooling tube 310 and the connection bus bar unit 230.

Fig. 24 is a bottom view illustrating the side structural unit when the side structural unit of fig. 15 is coupled to a battery cell, fig. 25 is an enlarged bottom view illustrating a main portion of the side structural unit of fig. 24, and fig. 26 is a side view illustrating a main portion of the side structural unit of fig. 24.

Referring to fig. 24 to 26, the bottom rib 415 of the side structural unit 400 may be disposed to protrude further downward (-Z-axis direction) to the bottom of the battery cell 100 without interfering with the exhaust part 31 of the battery cell 100. Therefore, when gas is discharged through the gas discharge portion 31 due to overheating of the battery cell 100, the gas can be discharged more rapidly without interference of the bottom rib 415.

Further, the bottom rib 415 may be provided to cover one side of the bottom of the battery cell 100 so that the battery cell 100 can be more firmly fixed in the side structural unit 400 when being received in the side structural unit 400.

Accordingly, the height (h 3) of the side structural unit 400 may be set to be greater than the height of the battery cell 100 so as to cover both the upper side and the lower side of the battery cell 100 in the height direction (Z-axis direction). For example, in the present embodiment, since the height of the battery cell 100 is 80mm, the height (h 3) of the side structural unit 400 may be longer than the height (h 3) of the battery cell 100 at both the upper side and the lower side of the battery cell 100.

Further, the height (h 3) of the side structural unit 400 may be set to a height capable of covering the thicknesses of the bus bar assembly 200 and the filling member 500 placed on the battery cell 100. Specifically, the height (h 3) of the side structural units 400 may be set in a range of about 85mm and 95mm in consideration of all the above thicknesses. More specifically, the height (h 3) of the side structural units 400 may be set to 90.3mm, approximately 90mm.

Referring again to fig. 2, the filling member 500 may fill the space between the cooling unit 300 and the plurality of battery cells 100 in the height direction (Z-axis direction) of the battery pack 1. Further, in fig. 2, for convenience of understanding, the filling member 500 is indicated by a dotted line in the shape of a hexahedron, and the filling member 500 may be filled in the entire space between the cooling unit 300 and the plurality of battery cells 100.

The filling member 500 may cover the upper and lower sides of the battery pack 1 (see fig. 2) to form a battery pack case structure of the battery pack 1 together with the side structural units 400.

In addition, the filling member 500 may more stably fix the plurality of battery cells 100 and improve the heat dissipation efficiency of the plurality of battery cells 100 to further improve the cooling performance of the battery cells 100.

The filling member 500 may be made of potting resin. The potting resin may be formed by injecting a diluted resin material into the plurality of battery cells 100 and curing it. Here, the injection of the resin material may be performed at a room temperature of about 15 to 25 ℃ to prevent thermal damage to the plurality of battery cells 100.

In particular, the filling member 500 may be made of silicone. The present disclosure is not limited thereto, and the filling member 500 may be made of a resin material other than silicone, which can improve the fixing and heat dissipation efficiency of the battery cell 100.

More specifically, since the filling member 500 covers the portion of the battery cell 100 that is not in contact with the cooling tube 310, the filling member 500 may guide the thermal balance of the battery cell 100 and prevent the cooling deviation of the battery cell 100, thereby preventing the local deterioration of the battery cell 100. In addition, the safety of the battery cell 100 may be significantly improved by preventing the local degradation of the battery cell 100.

In addition, when at least one specific battery cell 100 is damaged due to an abnormal condition among the plurality of battery cells 100, the filling member 500 may serve as an insulation function to prevent electrical connection to the neighboring battery cells 100.

Further, the filling member 500 may include a material having a high specific heat property (specific heat performance). Therefore, even in the case of rapid charge and discharge of the battery cell 100, the filling member 500 can improve the thermal mass to delay the temperature rise of the battery cell 100, thereby preventing rapid temperature rise of the battery cell 100.

Further, the filling member 500 may include a glass bulb. The glass bubbles can reduce the specific gravity of the filling member 500 to increase the energy density with respect to the weight.

In addition, the filling member 500 may include a material having high heat resistance. Accordingly, when a thermal event caused by overheating occurs in at least one specific battery cell 100 among the plurality of battery cells 100, the filling member 500 may effectively prevent thermal runaway toward an adjacent battery cell.

In addition, the filling member 500 may include a material having high flame retardant property. Accordingly, the filler member 500 may minimize the risk of fire occurrence when a thermal event caused by overheating occurs in at least one specific battery cell 100 among the plurality of battery cells 100.

The filling member 500 may be filled in the bus bar assembly 200 in addition to the battery cells 100. Specifically, the filling member 500 may be filled in the bus bar assembly 200 to cover the upper side of the bus bar assembly 200.

Here, the filling member 500 may be continuously filled between the bus bar assembly 200 and the battery cell 100 in the up-down direction (Z-axis direction) of the battery cell 100 without an isolation space or separation space between the bus bar assembly 200 and the battery cell 100.

Since the filling member 500 according to the present embodiment is continuously filled in the battery cell 100 and the bus bar assembly 200 without interruption, heat dissipation can be even achieved without causing heat dissipation deviation in the region between the battery cell 100 and the bus bar assembly 200, thereby significantly improving the cooling performance of the battery pack 1.

Further, the filling member 500 may be filled in a portion other than the outside of the side surface of the side structural unit 400. Here, the filling member 500 may be continuously filled in the battery cells 100, the bus bar assembly 200, and the side structural units 400 without interruption. Therefore, the cooling performance of the battery pack 1 can be further improved.

Hereinafter, the formation of the battery case structure by injecting the filling member 500 will be described in more detail.

Referring to fig. 27 to 29, a manufacturer or the like may inject and apply a filling member 500 provided as a silicon resin by using a resin injection apparatus I to form battery case structures of upper and lower sides of the battery pack 1 (see fig. 2) by means of the filling member 500 provided as a resin material. Specifically, the filling member 500 may fill up to the protrusion height h4 of the bottom rib 415 while covering the upper side of the bus bar assembly 200 in the upward direction (+z-axis direction) of the battery pack 1 and covering the lower side of the battery cell 100 in the downward direction (-Z-axis direction) of the battery pack 1. Here, the protrusion height h4 of the bottom rib 415 may be designed to be a predetermined height in consideration of the injection amount of the filling member 500.

In the process of injecting and coating the filling member 500 using the resin injection apparatus I, an injection guide S may be provided to the bottom of the side structural unit 400 so as to prevent the resin from leaking in the downward direction (-Z-axis direction) when the filling member 500 is injected. The injection guide S may be made of Teflon material or the like so as to be easily separated after the filling member 500 is cured.

In the injection and coating process of the filling member 500, the side structural unit 400 may be used as a mold for preventing resin leakage while supporting the battery cells 100 and the cooling unit 300 and the injection guide S.

Therefore, in the present embodiment, by means of the side structural unit 400, an additional injection guide jig structure in the lateral direction is not required in the injection and coating process of the filling member 500, thereby remarkably improving work efficiency while reducing manufacturing costs.

Further, since the side structural units 400 guide the accurate arrangement of the connection bus bar units 230 by means of the bus bar guide protrusions 416 inserted into the connection bus bar units 230, the connection bus bar units 230 can be effectively prevented from being twisted or misaligned when the filling member 500 is injected.

Further, with the guide protrusions 418 and the end guide protrusions 458 formed at the edges of the upper surfaces of the side structural units 400, injection accuracy of the filling member 500 is improved at the time of injecting the filling member 500, so that the filling member 500 can be easily injected to more firmly cover the bus bar assembly 200, and also overflow of the filling member 500 can be effectively prevented.

Here, the side structural unit 400 exposes components (e.g., the interconnect board 260, the connector terminals 290, and the cooling fluid inlet/outlet portion 370) connected to external devices, and thus problems such as interference with these components may not occur while the filling member 500 is injected or applied.

Therefore, in the present embodiment, since the battery case structure of the battery pack 1 (see fig. 1) is formed by means of the side structural units 400 and the filling members 500, the assembly process of the battery pack 1 can be simplified, thereby remarkably reducing the manufacturing cost to ensure cost competitiveness, compared to the related art in which the battery case structure is formed as a complex assembly of a plurality of plates.

Further, in the present embodiment, by means of the battery pack case structure prepared using the side structural unit 400 and the filling member 500, it is possible to reduce the entire size of the battery pack 1, as compared to the related art in which the battery pack case structure is provided as a battery cell frame structure composed of an assembly of a plurality of plates, thereby remarkably improving the energy density.

Fig. 30 is a view for illustrating a battery pack according to another embodiment of the present disclosure, and fig. 31 is an exploded perspective view illustrating the battery pack of fig. 30.

Since the battery pack 2 according to the present embodiment is similar to the battery pack 1 of the foregoing embodiment, substantially the same or similar features as the foregoing embodiment will not be described in detail, and features different from the foregoing embodiment will be described in detail.

Referring to fig. 30 and 31, the battery pack 2 may include a plurality of battery cells 100, a bus bar assembly 205, a cooling unit 300, a side structural unit 405, and a filling member 500.

The plurality of battery cells 100, the cooling unit 300, and the filling member 500 are substantially the same or similar to the previous embodiments, and thus will not be described in detail.

The busbar assembly 205 will be described in more detail with reference to the following related drawings.

Fig. 32 is a view for illustrating a bus bar assembly of the battery pack of fig. 30, and fig. 33 is a view for illustrating a high voltage bus bar unit of the bus bar assembly of fig. 32.

Referring to fig. 32 and 33 and fig. 31, the bus bar assembly 205 may include a main bus bar unit 210, a connection bus bar unit 230, an interconnection plate 260, high voltage bus bar units 270, 280, and a connector terminal 290.

The main bus bar unit 210, the connection bus bar unit 230, and the interconnection plate 260 are substantially the same as or similar to the previous embodiments, and thus will not be described in detail.

The high voltage bus bar units 270, 280 serve to secure electrical safety of the bus bar assembly 200, and may be formed to have a thickness greater than that of the main bus bar unit 210. As an example, in the present embodiment, the thickness of the main bus bar unit 210 may be set to 0.4mm, and the thickness of the high voltage bus bar units 270, 280 may be set to 4mm, which is greater than the thickness of the main bus bar unit 210.

The high voltage bus bar units 270, 280 may include a high voltage line member 270 and a connector mounting member 280.

The high voltage line member 270 is disposed at the bottom of the main busbar unit 210, and may be provided with a predetermined length for stabilizing the flow of current. The high-voltage line member 270 may be mounted to both ends of a main board 410 of a side structural unit 405 (described later) along the width direction (X-axis direction) of the battery pack 2. The high voltage line member 270 may be provided in plurality according to the number or capacity of the battery cells 100 of the battery pack 2. That is, the number of high voltage line members 270 may vary according to the number or capacity of the battery cells 100.

Hereinafter, the high-voltage line member 270 will be described in more detail.

The high voltage line member 270 may include a first high voltage line part 271, a second high voltage line part 273, and a connection line part 275.

The first high voltage line part 271 is formed to have a predetermined length and may be placed on the main board 410 to be disposed at the bottom of the main bus bar unit 210. Here, the first high voltage line part 271 may be formed to have a greater thickness than the main bus bar unit 210 in consideration of current capacity. The first high-voltage line portion 271 may be placed on a first line housing portion 419a of the main board 410 (described later).

The second high voltage line part 273 may be spaced apart from the first high voltage line part 271 in the height direction (Z-axis direction) of the battery pack 2, and may be placed on the bottom of the main board 410. The second high voltage line part 271 may be formed to have the same thickness as the first high voltage line part 271, and may form a current path together with the first high voltage line part 271.

The connection line portion 275 connects the first high voltage line portion 271 and the second high voltage line portion 273, and may be disposed at both sides of the main board 410 in the height direction (Z-axis direction) of the main board 410. The connection line portion 275 may be integrally formed with the first high voltage line portion 271 and the second high voltage line portion 273, and may form a current path together with the first high voltage line portion 271 and the second high voltage line portion 273.

In an embodiment, one of the first high voltage line part 271 and the second high voltage line part 273 may include a disconnection portion to ensure that current flows from the first high voltage line part 271 to the second high voltage line part 273 or vice versa through the connection line part 275.

The connection line portion 275 may be provided in plurality. The plurality of connection line parts 275 may be disposed to be spaced apart from each other by a predetermined distance in the width direction (X-axis direction) of the battery pack 2. Further, the connection line portion 275 may be provided between the cooling units 300 to prevent interference with the cooling units 300 in the width direction (X-axis direction) of the battery pack 2.

The connector mounting members 280 may be provided in a pair. The pair of connector mounting members 280 are disposed between the high-voltage line members 270, and may be mounted to a pair of end plates 450 (see fig. 34) of the side structural unit 405 (described later).

The pair of connector mounting members 280 may include a high voltage line portion 281 and a connector connection portion 285.

The high voltage line part 281 is formed to have a predetermined length, and may be placed on the end plate 450 to be disposed at the bottom of the main bus bar unit 210. The high-voltage line portion 281 may be placed on a connector mounting member accommodation portion 459 of an end plate 450 (described later). The upper side of the high-voltage line portion 281 may be disposed on the same line as the first high-voltage line portion 271 in the width direction (X-axis direction) of the battery pack 2.

The connector connection portion 285 may extend from the high-voltage line portion 281, and may be disposed on a side surface of the end plate 450 in a height direction (Z-axis direction). A connector terminal 290 (described later) may be mounted to the connector connection portion 285.

The connector terminals 290 are provided in a pair and may be connected to the connector mounting member 280. Specifically, the pair of connector terminals 290 may be respectively mounted to the connector connection portion 285 of each connector mounting member 280. The pair of connector terminals 290 may be mounted on a pair of end plates 450 (described later) in a state of being connected to the connector mounting member 280.

In the present embodiment, it is possible to enhance the electrical safety of the battery pack 2 and further improve the efficiency during charge and discharge by guiding the stable current in the battery pack 2 to flow through the high-voltage bus bar units 270, 280.

Fig. 34 is a view for illustrating a side structural unit of the battery pack of fig. 30, fig. 35 is a view for illustrating a main board of the side structural unit of fig. 33, fig. 36 is a view for illustrating an arrangement relationship of battery cells and a cooling unit by means of the side structural unit of fig. 34, and fig. 37 to 40 are views for illustrating mounting structures of the side structural unit and the high-voltage bus bar unit of fig. 34.

Referring to fig. 34 to 40 and 31, the side structural unit 405 may include a plurality of main boards 410 and a pair of end boards 450.

Each of the plurality of main boards 410 may include a first cell housing 411, a second cell housing 412, a middle wing 413, a bottom rib 415, a bus bar guide protrusion 416, a cooling unit insertion groove 417, and high voltage line member housing 419a, 419b.

The first cell housing 411, the second cell housing 412, the middle wing 413, the bottom rib 415, the bus bar guide protrusion 416, and the cooling unit insertion groove 417 are substantially the same as or similar to the previous embodiments, and thus will not be described in detail.

The high-voltage line member housing portions 419a, 419b may be formed at both ends of the main board 410 in the longitudinal direction (Y-axis direction). The first high-voltage line portion 271 and the second high-voltage line portion 273 of the high-voltage line member 270 may be placed on the high-voltage line member accommodation portions 419a, 419b.

The high-voltage line member housing portions 419a, 419b may include a first line housing portion 419a and a second line housing portion 419b.

The first line accommodating portion 419a may accommodate the first high-voltage line portion 271, and may be formed at edges of upper ends (+z-axis direction) of both ends of the main board 410 in the longitudinal direction (Y-axis direction). When the first high-voltage line portion 271 is accommodated, the first line accommodating portion 419a may be stepped to a predetermined depth to prevent the battery pack 2 from protruding upward toward the upper side (+z-axis direction). Here, the predetermined depth may be at least equal to the thickness of the first high-voltage line portion 271.

The second wire housing portion 419b may house the second high voltage wire portion 273, and may be formed at edges of lower ends (-Z axis direction) of both ends of the main board 410 in the longitudinal direction (Y axis direction). When the second high voltage wire part 273 is received, the second wire receiving part 419b may be stepped to a predetermined depth to prevent the battery pack 2 from protruding downward (-Z axis direction). Here, the predetermined depth may be at least equal to the thickness of the second high voltage wire part 273.

The pair of end plates 450 may include terminal holes 456, end guide protrusions 458, and connector mounting member receiving portions 459.

The terminal holes 456 and the end guide protrusions 458 are similar to the previous embodiments, and thus will not be described in detail.

The connector mounting member accommodation portion 459 may accommodate the high-voltage line portion 281, and may be formed at edges of upper ends (+z-axis direction) of both ends of the end plate 450 in the longitudinal direction (Y-axis direction). When the high-voltage wiring portion 281 is accommodated, the connector mounting member accommodation portion 459 may be stepped to a predetermined depth to prevent the battery pack 2 from protruding toward the upper side (+z-axis direction). Here, the predetermined depth may be at least equal to the thickness of the high-voltage line portion 281.

Further, the connector mounting member accommodation part 459 may accommodate a portion of the first high-voltage line part 271 that is placed on the first line accommodation part 419a of the main board 410 adjacent to the end plate 450 at the opposite side to the connector terminal 290. For this reason, the connector mounting member accommodation portion 459 may be disposed on the same line as the first line accommodation portion 419a in the width direction (X-axis direction) of the battery pack 2.

Referring to fig. 41 and 42, a manufacturer or the like may form upper and lower battery case structures of the battery pack 2 (see fig. 30) by injecting and applying the filling member 500 provided with silicone resin by means of the resin injection apparatus I and the injection guide S.

In the present embodiment, the filling member 500 may be filled at the upper side (+z-axis direction) of the battery pack 2 to cover a portion of the connection bus bar unit 230 and the main bus bar unit 210 of the bus bar assembly 200.

Here, the filling member 500 may be filled to the upper sides (+z-axis direction) of the main bus bar unit 210 and the connection bus bar unit 230 placed on the upper sides (+z-axis direction) of the side structural units 400 to cover only the electrode connection parts of the battery cells 100 electrically connected to the main bus bar unit 210 and the connection bus bar unit 230. That is, the filling member 500 may be filled in the main bus bar unit 210 and the connection bus bar unit 230 to a height capable of covering only the electrode connection portion bent downward (-Z axis direction) for electrical connection.

Specifically, the filling member 500 may be filled to cover only the positive and negative electrode bus bar holes 242 and 244 of the connection bus bar unit 230. More specifically, the filling member 500 may be filled until it is flush with the horizontal portion of the main bus bar unit 210 and the horizontal portion of the bus bar cover 240. Accordingly, after the filling member 500 is completely filled, on the upper surface (+z-axis direction) of the battery pack 2, the horizontal portion of the main bus bar unit 210 and the horizontal portion of the bus bar cover 240 connecting the bus bar units 230 may be partially exposed.

As described above, in the present embodiment, since the filling member 500 covers only the electrode connection parts of the battery cells 100 electrically connected to the main bus bar unit 210 and the connection bus bar unit 230 of the bus bar assembly 200 at the upper side (+z-axis direction) of the battery pack 1, it is possible to optimize the applied amount of the filling member 500 made of silicone while effectively securing the safety of the electrical connection.

Referring to fig. 43, a vehicle V may be provided as an electric vehicle or a hybrid electric vehicle, and may include at least one battery pack 1, 2 of the foregoing embodiments as an energy source.

In the present embodiment, since the above-described battery packs 1, 2 are provided in a compact structure having a high energy density, when the battery pack 1 is mounted to the vehicle V, a modular structure of a plurality of battery packs 1, 2 is easily achieved, and a relatively high degree of freedom of mounting can be ensured even for various internal space shapes of the vehicle V. That is, in the present embodiment, at least one battery pack 1, 2 may be provided as a battery pack case structure that is easily implemented in a modular structure and has a high degree of freedom in installation.

Furthermore, the longitudinal direction of the at least one battery pack 1, 2 may be arranged substantially perpendicular to the length direction of the vehicle V, such that the side structural units 400 provide protection for the plurality of battery cells 100 during a front or rear collision of the vehicle V.

According to the various embodiments described above, it is possible to provide the battery packs 1, 2 and the vehicle V including the battery pack 1 that can ensure rigidity while improving energy density.

Further, according to the various embodiments described above, it is possible to provide the battery packs 1, 2 and the vehicle V including the battery pack 1, which can improve cost competitiveness and manufacturing efficiency.

Further, according to the various embodiments described above, it is possible to provide the battery packs 1, 2 and the vehicle V including the battery packs 1, 2 that can improve the cooling performance.

The present disclosure has been described in detail. However, it should be understood that the detailed description and specific examples, while indicating exemplary embodiments of the disclosure, are given by way of illustration only, since various changes and modifications within the scope of the disclosure will become apparent to those skilled in the art from this detailed description.

Claims

1. A battery pack, the battery pack comprising:

a plurality of battery cells;

A bus bar assembly having a first side and a second side, the second side of the bus bar assembly being disposed to the first side of the plurality of battery cells and electrically connected to the plurality of battery cells;

a cooling unit disposed at the second side of the bus bar assembly and arranged between the plurality of battery cells along a longitudinal direction of the battery pack; and

a side structural unit configured to accommodate the cooling unit and the plurality of battery cells, wherein opposite ends of the cooling unit are fixed to the side structural unit.

2. The battery pack according to claim 1,

wherein the cooling unit includes:

a cooling tube having a predetermined length in the longitudinal direction of the battery pack and disposed between the plurality of battery cells;

a cooling channel disposed in the cooling tube and configured to circulate a cooling fluid for cooling the plurality of battery cells; and

a cooling fluid inlet/outlet portion connected to the cooling pipe to communicate with the cooling passage.

3. The battery pack according to claim 2,

wherein the cooling pipe is formed to have a shape corresponding to outer surfaces of the plurality of battery cells facing the cooling pipe in the width direction of the battery pack.

4. A battery pack according to claim 3,

wherein the cooling pipe includes a plurality of convex portions and a plurality of concave portions that are respectively formed convexly and concavely in the width direction of the battery pack and are alternately arranged along the longitudinal direction of the battery pack.

5. The battery pack according to claim 2,

wherein, the cooling channel includes:

at least one upper channel provided at an upper side of the cooling pipe to be provided near the bus bar assembly;

at least one lower channel provided at a lower side of the cooling tube to be spaced apart from the at least one upper channel; and

a connecting channel configured to connect the at least one lower channel and the at least one upper channel.

6. The battery pack according to claim 2,

wherein the side structural units have cooling unit insertion grooves provided at opposite ends of the side structural units to fix the opposite ends of the cooling units, respectively.

7. The battery pack according to claim 5,

the cooling pipe of the cooling unit is inserted between the plurality of battery cells arranged in front and rear rows in the width direction of the battery pack.

8. The battery pack according to claim 5,

wherein the opposite ends of the cooling unit are inserted into the cooling unit insertion grooves provided at the opposite ends of the side structural units.

9. The battery pack according to claim 8,

wherein the cooling fluid inlet/outlet portion is arranged to protrude out of the side structural unit.

10. The battery pack according to claim 8,

wherein at least one end of the side structural unit is formed to be shorter than one surface of the plurality of battery cells, which is in contact with the cooling pipe.

11. The battery pack of claim 1, further comprising:

and a filling member filling in a space between the cooling unit and the plurality of battery cells.

12. The battery pack according to claim 11,

wherein the filling member is made of potting resin.

13. The battery pack according to claim 12,

wherein the filler member is made of silicone.

14. The battery pack according to claim 11,

wherein the filling member fills in the bus bar assembly to cover the first side of the bus bar assembly.

15. A battery pack housing structure of at least one battery pack, the battery pack being the battery pack according to claim 1.

16. A vehicle, the vehicle comprising:

the battery housing structure of claim 15,

wherein the longitudinal direction of the at least one battery pack is arranged perpendicular to the length direction of the vehicle such that the side structural units provide protection for the plurality of battery cells during a front or rear collision of the vehicle.

17. The battery pack of claim 1, wherein the plurality of battery cells are compressed in a height direction of a cylindrical can of each of the plurality of battery cells.

18. A battery pack, the battery pack comprising:

a cooling unit having convex and concave portions alternately arranged in a longitudinal direction of the battery pack;

a plurality of battery cells arranged in two groups along the longitudinal direction of the battery pack, a first group being arranged on a first side of the cooling unit and a second group being arranged on a second side of the cooling unit;

A side structural unit disposed in a longitudinal direction of the battery pack, the side structural unit including a first main plate and a second main plate separated from each other,

wherein the first motherboard accommodates the first group of the plurality of battery cells and the second motherboard accommodates the second group of the plurality of battery cells, and

wherein the curvature of the convex portion and the concave portion corresponds to the curvature of the plurality of battery cells.

19. The battery pack of claim 18, wherein each of the first and second main plates is closest to the cooling unit at a respective lobe.

20. The battery pack of claim 18, wherein each battery cell contacts only one of the first motherboard and the second motherboard at a first side and contacts one recess of the cooling unit at a second side.