Battery pack and automobile including same

Abstract

A battery pack according to one embodiment of the present invention includes a plurality of battery cells, a cooling unit arranged between the battery cells along the longitudinal direction of the battery pack, and a side structural unit that houses the cooling unit and the battery cells, and the battery cells, the cooling unit, and the side structural unit are configured to be arranged at a predetermined distance ratio that has already been set for close contact with each other.

Description

[Technical Field]

[0001] The present invention relates to a battery pack and a vehicle including the same.

[0002] This application claims priority based on Korean Patent Application No. 10-2021-0187839, filed on December 24, 2021, and the entire contents disclosed in the specification and drawings of that application are incorporated herein by reference. [Background technology]

[0003] Secondary batteries, which have high applicability to various products and electrical properties such as high energy density, are commonly used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs), which are powered by electrical sources. These secondary batteries not only have the primary advantage of dramatically reducing the use of fossil fuels, but also have the advantage of not producing any by-products from energy use, making them environmentally friendly and drawing attention as a new energy source for improving energy efficiency.

[0004] Currently, secondary batteries such as lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries are widely used. The operating voltage of such unit secondary battery cells, i.e., unit battery cells, is approximately 2.5V to 4.5V. Therefore, when a higher output voltage is required, a battery pack is constructed by connecting multiple battery cells in series. Alternatively, a battery pack may be constructed by connecting multiple battery cells in parallel depending on the required charge / discharge capacity of the battery pack. Therefore, the number of battery cells included in the battery pack may be variously set depending on the required output voltage or charge / discharge capacity.

[0005] Meanwhile, when a battery pack is constructed by connecting a plurality of battery cells in series / parallel, a common method is to first construct a battery module including at least one battery cell, and then add other components to the at least one battery module to construct a battery pack or a battery rack.

[0006] A conventional battery pack generally includes a plurality of battery cells and a cell frame that houses the plurality of battery cells. The conventional cell frame generally includes an assembly of a plurality of plates, such as a front plate, a rear plate, a side plate, a bottom plate, and a top plate, for housing the plurality of battery cells and ensuring rigidity.

[0007] However, in the case of conventional battery packs, the cell frame structure formed by assembling a plurality of plates increases manufacturing costs, complicates the assembly process, and is disadvantageous in terms of price competitiveness and manufacturing efficiency.

[0008] Furthermore, in the case of a conventional battery pack, since the battery pack has a cell frame structure formed by an assembly of a plurality of plates, the overall size of the battery pack increases, which is disadvantageous in terms of energy density.

[0009] Furthermore, in the case of conventional battery packs, the placement of a cooling unit for cooling the battery cells may reduce the energy density of the entire battery pack, and interference between the cooling unit and multiple plates may reduce cooling performance and efficiency. Summary of the Invention [Problem to be solved by the invention]

[0010] Therefore, an object of the present invention is to provide a battery pack that can improve energy density and ensure optimal cooling performance, and a vehicle including the same. [Means for solving the problem]

[0011] In order to achieve the above object, the present invention provides a battery pack including a plurality of battery cells, a cooling unit arranged between the plurality of battery cells along the longitudinal direction of the battery pack, and a side structural unit that houses the cooling unit and the plurality of battery cells, wherein the battery cells, the cooling unit, and the side structural unit are configured to be arranged at a predetermined distance ratio that is already set to ensure close contact with each other.

[0012] Preferably, the side structural unit may include a first cell accommodating portion and a second cell accommodating portion having a concave shape and arranged alternately, and the distance between the center of a battery cell provided in the first cell accommodating portion and the center of a battery cell provided in the second cell accommodating portion may be configured to be determined according to the thickness of the side structural unit.

[0013] Preferably, the cooling unit may include a cooling tube disposed between the plurality of battery cells, and a cooling flow path disposed within the cooling tube for circulating a cooling fluid for cooling the battery cells, and the distance between the centers of adjacent battery cells in contact with one side of the cooling tube may be configured to be determined in conjunction with the distance between the centers of battery cells disposed opposite each other across the cooling tube.

[0014] Preferably, the distance between the centers of the battery cells facing each other across the cooling tube may be a distance that reflects the thickness of the cooling tube.

[0015] Preferably, the distance between the center of the battery cell provided in the first cell accommodating portion and the center of the battery cell provided in the second cell accommodating portion, the distance between the centers of adjacent battery cells in contact with one side of the cooling tube, and the distance between the centers of battery cells arranged opposite each other across the cooling tube may be determined in consideration of the diameter of the battery cell, the thickness of the cooling tube, and the contact angle between the battery cell and the cooling tube.

[0016] Preferably, the contact angle between the battery cell and the cooling tube may be 60°.

[0017] Preferably, the minimum thickness of the first cell receiving portion and the second cell receiving portion may be half the distance between the battery cells between the first cell receiving portion and the second cell receiving portion.

[0018] Preferably, when the battery cells are received in the first cell receiving portion and the second cell receiving portion, a predetermined gap space may be formed between the first cell receiving portion and the second cell receiving portion.

[0019] Preferably, when the battery cells are accommodated in the first cell accommodating portion and the second cell accommodating portion, the gap space may be formed in a remaining area excluding an innermost area of ​​the concave shape of the first cell accommodating portion and the second cell accommodating portion.

[0020] Preferably, the battery cell may contact the inner surfaces of the first cell accommodating portion and the second cell accommodating portion only in an area of ​​the innermost portion of the concave shape.

[0021] Preferably, the gap space can be filled with a filling member.

[0022] The present invention also provides a vehicle including the above-described battery pack, wherein a longitudinal direction of at least one battery pack is arranged perpendicular to a longitudinal direction of the vehicle so that the side structural unit can protect a plurality of the battery cells in the event of a frontal or rearal collision of the vehicle. [Effects of the Invention]

[0023] According to an embodiment of the present invention, it is possible to provide a battery pack and a vehicle including the same that can improve energy density and ensure optimal cooling performance.

[0024] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical concepts of the present invention. Therefore, the present invention should not be interpreted as being limited to the matters described in the drawings. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a diagram illustrating a battery pack according to an embodiment of the present invention; [Figure 2] FIG. 2 is an exploded perspective view of the battery pack of FIG. 1. [Figure 3] 3 is a diagram for explaining a battery cell included in the battery pack of FIG. 2. FIG. [Figure 4] FIG. 4 is a partial cross-sectional view showing the internal structure of the battery cell of FIG. 3. [Figure 5] FIG. 4 is a partial cross-sectional view showing the upper structure of the battery cell of FIG. 3. [Figure 6] FIG. 4 is a partial cross-sectional view showing the lower structure of the battery cell of FIG. 3. [Figure 7] FIG. 4 is a bottom view of the battery cell of FIG. 3. [Figure 8] 3 is a diagram illustrating a bus bar assembly of the battery pack shown in FIG. 2. FIG. [Figure 9] 9 is a diagram illustrating a coupling busbar unit of the busbar assembly shown in FIG. 8. FIG. [Figure 10] FIG. 10 is an exploded perspective view of the coupling busbar unit of FIG. 9. [Figure 11] 10 is an enlarged view for explaining a main part of the coupling busbar unit of FIG. 9. FIG. [Figure 12] 3 is a diagram for explaining a cooling unit of the battery pack shown in FIG. 2. FIG. [Figure 13] FIG. 13 is an exploded perspective view of the cooling unit of FIG. 12. [Figure 14] FIG. 13 is a cross-sectional view of the cooling unit of FIG. [Figure 15] 3 is a diagram for explaining a side structure unit of the battery pack shown in FIG. 2. FIG. [Figure 16] 16 is a diagram for explaining a main plate of the side structural unit of FIG. 15. FIG. [Figure 17] 16 is a diagram for explaining the connection structure between the battery cell and the cooling unit through the side structure unit of FIG. 15. FIG. [Figure 18] 16 is a diagram for explaining the connection structure between the battery cell and the cooling unit through the side structure unit of FIG. 15. FIG. [Figure 19] 16 is a diagram for explaining the connection structure between the battery cell and the cooling unit through the side structure unit of FIG. 15. FIG. [Figure 20] 16 is a diagram for explaining the connection structure between the battery cell and the cooling unit through the side structure unit of FIG. 15. FIG. [Figure 21] 16 is a diagram for explaining the positional relationship between the battery cell and the cooling unit through the side structure unit of FIG. 15. FIG. [Figure 22] 16 is a diagram for explaining the positional relationship between the battery cell and the cooling unit through the side structure unit of FIG. 15. FIG. [Figure 23] 23 is a diagram for explaining the contact structure between the battery cell in FIG. 22 and the cooling unit. FIG. [Figure 24] 23 is a diagram for explaining the contact structure between the battery cell in FIG. 22 and the cooling unit. FIG. [Figure 25] 23 is a diagram for explaining the contact structure between the battery cell in FIG. 22 and the cooling unit. FIG. [Figure 26] 16 is a diagram showing the bottom surface of the side structure unit when the side structure unit and the battery cell are coupled together in FIG. 15. FIG. [Figure 27] FIG. 27 is an enlarged bottom view of a main part of the side structure unit of FIG. 26. [Figure 28] FIG. 27 is a side view of the main part of the side structure unit of FIG. 26. [Figure 29] 3 is a diagram illustrating the formation of a pack case structure by injecting a filler material into the battery pack shown in FIG. 2. FIG. [Figure 30] 3 is a diagram illustrating the formation of a pack case structure by injecting a filler material into the battery pack shown in FIG. 2. FIG. [Figure 31] 3 is a diagram illustrating the formation of a pack case structure by injecting a filler material into the battery pack shown in FIG. 2. FIG. [Figure 32] 10A and 10B are diagrams illustrating a battery pack according to another embodiment of the present invention. [Figure 33] FIG. 33 is an exploded perspective view of the battery pack of FIG. 32. [Figure 34] 34 is a diagram for explaining a bus bar assembly of the battery pack shown in FIG. 33. FIG. [Figure 35] 35 is a diagram for explaining a high-voltage busbar unit of the busbar assembly shown in FIG. 34. FIG. [Figure 36] 34 is a diagram for explaining a side structure unit of the battery pack shown in FIG. 33. FIG. [Figure 37] FIG. 37 is a diagram for explaining the main plate of the side structural unit shown in FIG. 36. [Figure 38] 37 is a diagram for explaining the positional relationship between the battery cell and the cooling unit through the side structure unit of FIG. 36. FIG. [Figure 39] 37 is a diagram for explaining the mounting structure of the side structure unit and the high-voltage busbar unit of FIG. 36. FIG. [Figure 40]37 is a diagram for explaining the mounting structure of the side structure unit and the high-voltage busbar unit of FIG. 36. FIG. [Figure 41] 37 is a diagram for explaining the mounting structure of the side structure unit and the high-voltage busbar unit of FIG. 36. FIG. [Figure 42] 37 is a diagram for explaining the mounting structure of the side structure unit and the high-voltage busbar unit of FIG. 36. FIG. [Figure 43] 33 is a diagram for explaining the injection of a filling material into the battery pack of FIG. 32. FIG. [Figure 44] 33 is a diagram for explaining the injection of a filling material into the battery pack of FIG. 32. FIG. [Figure 45] FIG. 10 is a diagram illustrating a vehicle according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0026] The present invention will be more clearly understood by describing preferred embodiments of the present invention in detail below with reference to the accompanying drawings. The following embodiments are shown by way of example to facilitate understanding of the invention, and it should be understood that the present invention can be implemented by modifying various aspects of the following embodiments. In addition, the accompanying drawings may be drawn not to scale, and the dimensions of some components may be exaggerated to facilitate understanding of the invention.

[0027] FIG. 1 is a diagram illustrating a battery pack according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the battery pack of FIG.

[0028] 1 and 2, a battery pack 1 may be installed in an electric vehicle or a hybrid vehicle as an energy source. Hereinafter, the battery pack 1 installed in such an electric vehicle will be described in more detail with reference to the related drawings.

[0029] The battery pack 1 may include a plurality of battery cells 100, a busbar assembly 200, a cooling unit 300, a side structural unit 400, and a filling member 500.

[0030] The plurality of battery cells 100 are secondary batteries and may be cylindrical secondary batteries, pouch-type secondary batteries, or prismatic secondary batteries. Hereinafter, in this embodiment, the description will be limited to the case where the plurality of battery cells 100 are cylindrical secondary batteries.

[0031] The battery cell 100 will be described in more detail below with reference to the related drawings.

[0032] FIG. 3 is a diagram for explaining a battery cell included in the battery pack shown in FIG. 2, FIG. 4 is a partial cross-sectional view showing the internal structure of the battery cell of FIG. 3, FIG. 5 is a partial cross-sectional view showing the upper structure of the battery cell of FIG. 3, FIG. 6 is a partial cross-sectional view showing the lower structure of the battery cell of FIG. 3, and FIG. 7 is a bottom view of the battery cell of FIG. 3.

[0033] 3 to 7, the battery cell 100 includes an electrode assembly 10, a battery can 20, a cap plate 30, and a first electrode terminal 40. In addition to the above-mentioned components, the battery cell 100 may further include an insulating gasket 50 and / or an upper current collecting plate 60 and / or an insulating plate 70 and / or a lower current collecting plate 80 and / or a sealing gasket 90.

[0034] The electrode assembly 10 includes a first electrode plate having a first polarity, a second electrode plate having a second polarity, and a separator interposed between the first and second electrode plates. The first electrode plate is a positive or negative electrode plate, and the second electrode plate has the opposite polarity to the first electrode plate.

[0035] The electrode assembly 10 may be in the form of a jelly roll. That is, the electrode assembly 10 may be manufactured by sequentially stacking a first electrode plate, a separator, and a second electrode plate at least once, and winding the stack around a winding center C. In this case, a separator may be provided on the outer periphery of the electrode assembly 10 to insulate it from the battery can 20.

[0036] The first electrode plate includes a first electrode collector and a first electrode active material coated on one or both sides of the first electrode collector. An uncoated portion where the first electrode active material is not coated is present at one end of the first electrode collector in the width direction (Z-axis direction). The uncoated portion functions as a first electrode tab. The first electrode tab 11 is provided at the upper portion in the height direction (Z-axis direction) of the electrode assembly 10 housed in the battery can 20.

[0037] The second electrode plate includes a second electrode collector and a second electrode active material coated on one or both sides of the second electrode collector. An uncoated portion where the second electrode active material is not coated exists at the other end of the second electrode collector in the width direction (Z-axis direction). The uncoated portion functions as a second electrode tab 12. The second electrode tab 12 is provided at the lower part in the height direction (Z-axis direction) of the electrode assembly 10 housed in the battery can 20.

[0038] The battery can 20 is a cylindrical container having an opening at the bottom and made of a conductive metal material. The side and top surfaces of the battery can 20 are integrally formed. The top surface of the battery can 20 has a substantially flat shape. The battery can 20 accommodates the electrode assembly 10 through the opening at the bottom, along with the electrolyte.

[0039] 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.

[0040] The battery can 20 may have a beading portion 21 and a crimping portion 22 formed at its lower end. The beading portion 21 is formed at the bottom of the electrode assembly 10. The beading portion 21 is formed by pressing the outer circumferential surface of the battery can 20. The beading portion 21 prevents the electrode assembly 10, which has a size corresponding to the width of the battery can 20, from slipping out of an opening formed at the lower end of the battery can 20, and may function as a support on which the cap plate 30 is placed.

[0041] The crimping portion 22 is formed below the beading portion 21. The crimping portion 22 is bent and extends to surround the outer circumferential surface of the cap plate 30 disposed below the beading portion 21 and a portion of the lower surface of the cap plate 30.

[0042] The cap plate 30 is a component made of a conductive metal material and covers an opening formed at the bottom of the battery can 20. That is, the cap plate 30 constitutes the bottom surface of the battery cell 100. The cap plate 30 is placed on a beading portion 21 formed on the battery can 20 and fixed by a crimping portion 22. A sealing gasket 90 may be interposed between the cap plate 30 and the crimping portion 22 of the battery can 20 to ensure airtightness of the battery can 20.

[0043] The cap plate 30 may further include a vent portion 31 formed to prevent an increase in internal pressure due to gas generated inside the battery can 20. The vent portion 31 corresponds to a region of the cap plate 30 that is thinner than the surrounding region. The vent portion 31 is structurally weaker than the surrounding region. Therefore, if an abnormality occurs in the battery cell 100 and the internal pressure increases above a certain level, the vent portion 31 breaks, allowing the gas generated inside the battery can 20 to be released.

[0044] A hole may be pre-formed in the upper surface of the battery can 20 before disposing the first electrode terminal 40 and the insulating gasket 50, but the hole may be formed in other ways. For example, the hole may be formed while inserting the first electrode terminal 40, or a hole of a different diameter may be pre-formed, or the upper surface may be cut out, or the first electrode terminal 40 may be inserted into a pre-cut upper surface. That is, the hole may be enlarged to a desired size, or a small hole may be formed by cutting out and then expanded to a desired size. Of course, other methods of forming a hole may also be used.

[0045] The battery cell 100 according to an embodiment of the present invention has a structure in which both the positive and negative electrode terminals are located at the upper portion, and therefore the structure of the upper portion is more complex than the structure of the lower portion. Therefore, a vent portion 31 may be formed in a cap plate 30 forming the lower surface of the battery cell 100 to smoothly release gas generated inside the battery can 20.

[0046] The vent portion 31 may be formed continuously in a circular shape on the cap plate 30. However, without being limited thereto, the vent portion 31 may be formed discontinuously in a circular shape on the cap plate 30, or may be formed in a linear shape or other shapes.

[0047] The first electrode terminal 40 is made of a conductive metal material and passes through the top surface of the battery can 20 to be electrically connected to the first electrode tab 11 of the electrode assembly 10. Therefore, the first electrode terminal 40 has a first polarity. The first electrode terminal 40 is electrically insulated from the battery can 20, which has a second polarity.

[0048] 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 inserted terminal portion 42 penetrates the center of the upper surface of the battery can 20 and is electrically connected to the first electrode tab 11. The inserted terminal portion 42 may be rivet-connected to the inner surface of the battery can 20.

[0049] The top surface of the battery can 20 and the first electrode terminal 40 have opposite polarities and face the same direction. In addition, a step may be formed between the first electrode terminal 40 and the top surface of the battery can 20. Specifically, if the top surface of the battery can 20 has a flat shape or a shape that protrudes upward at its center, the exposed terminal portion 41 of the first electrode terminal 40 may protrude further above the top surface of the battery can 20. Conversely, if the top surface of the battery can 20 has a concave shape that is concave downward at its center, i.e., toward the electrode assembly 10, the top surface of the battery can 20 may protrude further above the exposed terminal portion 41 of the first electrode terminal 40.

[0050] The insulating gasket 50 is interposed between the battery can 20 and the first electrode terminal 40 to prevent the battery can 20 and the first electrode terminal 40, which have opposite polarities, from contacting each other. As a result, the upper surface of the battery can 20, which has a substantially flat shape, can function as the second electrode terminal of the battery cell 100.

[0051] The insulating gasket 50 includes an exposed portion 51 and an inserted portion 52. The exposed portion 51 is interposed between the exposed terminal portion 41 of the first electrode terminal 40 and the battery can 20. The inserted portion 52 is interposed between the inserted terminal portion 42 of the first electrode terminal 40 and the battery can 20. The insulating gasket 50 may be made of, for example, a resin material having insulating properties.

[0052] When the insulating gasket 50 includes a resin material, the insulating gasket 50 can be bonded to the battery can 20 and the first electrode terminal 40 by, for example, heat sealing. In this case, the airtightness at the bonding interface between the insulating gasket 50 and the first electrode terminal 40 and the bonding interface between the insulating gasket 50 and the battery can 20 can be strengthened.

[0053] The entire upper surface of the battery can 20, excluding the area occupied by the first electrode terminal 40 and the insulating gasket 50, corresponds to a second electrode terminal 20a having an opposite polarity to the first electrode terminal 40.

[0054] A battery cell 100 according to an embodiment of the present invention is provided with a first electrode terminal 40 having a first polarity and a second electrode terminal 20a electrically insulated from the first electrode terminal 40 and having a second polarity, on one side of the battery cell in its longitudinal direction (Z-axis direction). That is, in the battery cell 100 according to an embodiment of the present invention, a pair of electrode terminals (the first electrode terminal 40 and the second electrode terminal 20a) are positioned in the same direction, so that when a plurality of battery cells 100 are electrically connected, electrical connection components such as a bus bar assembly 200 (described below) can be disposed on only one side of the battery cell 100. This simplifies the structure of the battery pack 1 and improves energy density.

[0055] Hereinafter, the bus bar assembly 200 for electrical connection with the plurality of battery cells 100 will be described in more detail.

[0056] 2, the bus bar assembly 200 may be provided on one side of the battery cell 100, specifically, on the upper side (+Z-axis direction) of the battery cell 100, and may be electrically connected to a plurality of the battery cells 100. The electrical connection of the bus bar assembly 200 may be parallel and / or series connection.

[0057] The bus bar assembly 200 is electrically connected to the first electrode terminals 40 (see FIG. 3) having a first polarity of the plurality of battery cells 100 and the second electrode terminals 20a (see FIG. 3) of the battery cans 20 (see FIG. 3) having a second polarity, and may be electrically connected to an external charge / discharge line or the like through a connector terminal 290 or the like. Here, the first polarity may be a positive pole, and the second polarity may be a negative pole.

[0058] The configuration of the bus bar assembly 200 will be described in more detail below.

[0059] FIG. 8 is a diagram illustrating the busbar assembly of the battery pack shown in FIG. 2 , FIG. 9 is a diagram illustrating the connecting busbar unit of the busbar assembly shown in FIG. 8 , FIG. 10 is an exploded perspective view of the connecting busbar unit of FIG. 9 , and FIG. 11 is an enlarged view illustrating a main portion of the connecting busbar unit of FIG. 9 .

[0060] 8 to 11 and 2, the busbar assembly 200 may include a main busbar unit 210, a connecting busbar unit 230, an interconnection board 260, and a connector terminal 290.

[0061] A plurality of main busbar units 210 may be provided and may be electrically connected to battery cells 100 arranged at the outermost positions in the longitudinal direction (Y-axis direction) of the battery pack 1. The main busbar units 210 may be electrically connected to connector terminals 290, which will be described later.

[0062] The connecting busbar units 230 are arranged between the main busbar units 210 in the longitudinal direction (Y-axis direction) of the battery pack 1, are electrically connected to the plurality of battery cells 100, and may cover the plurality of battery cells 100.

[0063] The connecting bus bar unit 230 may be provided in a size sufficient to cover all of the battery cells 100, or a plurality of connecting bus bar units 230 may be provided to cover the battery cells 100. Hereinafter, the present embodiment will be described in terms of a case in which a plurality of connecting bus bar units 230 are provided.

[0064] Each of the plurality of connecting busbar units 230 may include a busbar cover 240 and a sub-busbar 250 .

[0065] The bus bar cover 240 may be configured in a substantially flat plate shape and cover the upper sides of the plurality of battery cells 100. The shape and size of the bus bar cover 240 may vary depending on the number and capacity of the battery cells 100 required by the battery pack 1.

[0066] The bus bar cover 240 may be made of an insulating material. For example, the bus bar cover 240 may include a polyimide film. However, the bus bar cover 240 is not limited thereto, and may include other insulating members made of insulating materials.

[0067] The bus bar covers 240 may be provided in pairs and coupled to each other to have corresponding shapes and sizes in the vertical direction (Z-axis direction) of the battery pack 1. Here, a sub-bus bar 250 (described later) may be a single layer and may be inserted between the pair of bus bar covers 240.

[0068] Such a busbar cover 240 may include a positive busbar hole 242 , a negative busbar hole 244 , and a guide hole 246 .

[0069] The positive electrode busbar hole 242 has an opening space of a predetermined size and may be provided in plurality. A positive electrode connecting portion 254 (described later) may be exposed through the positive electrode busbar hole 242. Here, the positive electrode busbar hole 242 may be formed to have an opening space larger than the size of the positive electrode connecting portion 254 (described later) in order to improve process operability and injection efficiency of the filler 500 (described later).

[0070] The positive electrode bus bar hole 242 can more efficiently guide the electrical connection between a positive electrode connector 254 (described later) and the first electrode terminal 40 (see FIG. 3) which is the positive electrode of the battery cell 100.

[0071] Furthermore, it is possible to significantly improve the injection efficiency of the filling member 500 when injecting the filling member 500 described later through the opening space of the positive bus bar hole 242. Specifically, the filling member 500 provided as a potting resin described later can be directly injected in the vertical direction (Z-axis direction) from above the battery pack 1 downward through the opening space of the positive bus bar hole 242, thereby significantly improving the injection efficiency between the battery cells 100.

[0072] The negative electrode busbar hole 244 is disposed opposite the positive electrode busbar hole 242, has an opening space of a predetermined size like the positive electrode busbar hole 242, and may be provided in plurality. Here, the negative electrode busbar hole 244 may be formed to have an opening space larger than the size of a negative electrode connecting portion 256 (described later) in order to improve process operability and injection efficiency of a filler 500 (described later).

[0073] The negative electrode busbar hole 244 can more efficiently guide the electrical connection between the negative electrode connecting portion 256 (described later) and the battery can 20 (see FIG. 3), which is the negative electrode of the battery cell 100, specifically, the second electrode terminal 20a.

[0074] Furthermore, it is possible to significantly improve the injection efficiency of the filling member 500 when injecting a filling member 500 (described later) through the opening space of the negative bus bar hole 244. Specifically, the filling member 500 (described later) provided as a potting resin can be directly injected from above the battery pack 1 downward in the vertical direction (Z-axis direction) through the opening space of the negative bus bar hole 244, thereby significantly improving the injection efficiency between the battery cells 100.

[0075] The guide holes 246 may guide the assembly position of the bus bar assembly 200. Specifically, the guide holes 246 may fix the connecting bus bar unit 230 to the side structure unit 400 and guide the correct position arrangement of the connecting bus bar unit 230.

[0076] A plurality of guide holes 246 may be provided, into which bus bar guide protrusions 416 of the side structural unit 400, which will be described later, may be inserted.

[0077] The sub-busbar 250 is for electrical connection with the first electrode terminal 40, which is a positive electrode, and the second electrode terminal 20a, which is a negative electrode, of the plurality of battery cells 100, and may be provided on the upper side of the busbar cover 240 or inserted into a pair of busbar covers 240. Hereinafter, in the present embodiment, the sub-busbar 250 will be described only as being inserted into or coupled to the busbar cover 240.

[0078] Such a sub-busbar 250 may include a busbar bridge 252 , a positive electrode connection portion 254 , and a negative electrode connection portion 256 .

[0079] The bus bar bridge 252 may be inserted into the bus bar cover 240 and formed to a predetermined length along the width direction (X-axis direction) of the battery pack 1. The bus bar bridge 252 may be configured in a shape corresponding to the arrangement structure of the battery cells 100 in the width direction (X-axis direction) of the battery pack 1 so as to improve the efficiency of electrical connection with the battery cells 100. Thus, in the present embodiment, the bus bar bridge 252 may be arranged in a zigzag pattern in the width direction (X-axis direction) of the battery pack 1.

[0080] A plurality of such bus bar bridges 252 may be provided. The plurality of bus bar bridges 252 may be inserted into the bus bar cover 240 and spaced apart from each other by a predetermined distance in the longitudinal direction (Y-axis direction) of the battery pack 1.

[0081] The busbar bridge 252 may be made of a conductive material. For example, the busbar bridge 252 may be made of a metal material such as aluminum or copper. However, the busbar bridge 252 is not limited thereto, and may of course be made of other materials for electrical connection.

[0082] The positive electrode connector 254 may extend integrally from the bus bar bridge 252 and be disposed within the positive electrode bus bar hole 242. The positive electrode connector 254 may be electrically connected to the first electrode terminal 40 (see FIG. 3 ), which is the positive electrode of the battery cell 100. The electrical connection may be achieved through a welding process for electrical connection, such as laser welding or ultrasonic welding.

[0083] The connection between the positive electrode connector 254 and the positive electrode (first electrode terminal 40) of the battery cell 100 is performed in the open space of the positive electrode bus bar hole 242, so that a welding process for the connection can be performed directly in the open space without any additional process during the connection.

[0084] The negative electrode connector 256 may extend integrally from the bus bar bridge 252, protrude in the opposite direction from the positive electrode connector 254, and be disposed in the negative electrode bus bar hole 244. The negative electrode connector 256 may be electrically connected to the second electrode terminal 20a (see FIG. 3 ), which is the negative electrode of the battery cell 100. The electrical connection may be achieved through a welding process for electrical connection, such as laser welding or ultrasonic welding.

[0085] The connection between the negative electrode connector 256 and the negative electrode (second electrode terminal 20a) of the battery cell 100 is performed in the open space of the negative electrode bus bar hole 244, so that a welding process for the connection can be performed directly in the open space without any additional process during the connection.

[0086] The interconnection board 260 may be connected to the external sensing line and may be provided at one end (-Y-axis direction) of the battery pack 1. The position of the interconnection board 260 may be changed depending on the design, and may be provided at another position where the interconnection board 260 can be connected to the external sensing line. Furthermore, a plurality of interconnection boards 260 may be provided depending on the number and capacity of the battery cells 100 of the battery pack 1.

[0087] The interconnection board 260 may be exposed to the outside of the battery pack 1 for connection to the external sensing line. The external sensing line may connect the interconnection board 260 to a battery management system (not shown). The battery management system may determine the state of charge of the battery cells connected in parallel based on the voltages of the battery cells connected in parallel.

[0088] The interconnection board 260 may include a thermistor for checking the temperature state of the battery cell 100. The thermistor may be built into the interconnection board 260 or may be separately attached to the outside of the interconnection board 260. The connector terminals 290 may be provided in pairs. The pair of connector terminals 290 may be configured as high-voltage connector terminals for connection to external charge / discharge lines.

[0089] Referring further to FIG. 2, the cooling unit 300 is for cooling the battery cells 100 and is disposed below the busbar assembly 200 (-Z axis direction) and may be disposed between a plurality of the battery cells 100 along the longitudinal direction (Y axis direction) of the battery pack 1.

[0090] A plurality of such cooling units 300 may be provided.

[0091] The plurality of cooling units 300 may be arranged to face the plurality of battery cells 100 in the width direction (X-axis direction) of the battery pack 1. Here, the plurality of cooling units 300 may be arranged to come into contact with the facing battery cells 100 in order to improve cooling performance.

[0092] The cooling unit 300 will be described in more detail below.

[0093] 12 is a diagram for explaining the cooling unit of the battery pack shown in FIG. 2, FIG. 13 is an exploded perspective view of the cooling unit of FIG. 12, and FIG. 14 is a cross-sectional view of the cooling unit of FIG.

[0094] 12 to 14 and 2, the cooling unit 300 may include a cooling tube 310, a cooling passage 350, and a cooling fluid inlet / outlet 370.

[0095] The cooling tube 310 is formed to 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 therein for circulating a cooling fluid, which will be described later. In the present embodiment, the cooling fluid may be water, but may also include one or more fluids capable of exchanging heat with the surrounding environment.

[0096] The cooling tube 310 may be formed in 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.

[0097] Such a cooling tube 310 may be formed so that a plurality of convex portions 312 and concave portions 316 formed in an uneven shape toward the width direction (X-axis direction) of the battery pack 1 are alternately arranged along the longitudinal direction (Y-axis direction) of the battery pack 1.

[0098] The cooling tube 310 may be disposed to contact outer surfaces of the battery cells 100 to further enhance the cooling performance of the battery cells 100. The cooling tube 310 may be adhered and fixed to the battery cells 100 using a filling member 500 (described below) or a separate adhesive member.

[0099] A cooling fluid guide portion 318 for guiding a cooling fluid into a cooling channel 350 (described later) may be provided at one end (-Y-axis direction) of the cooling tube 310. The cooling fluid guide portion 318 may be provided in pair and formed at one end (-Y-axis direction) of the cooling tube 310 in the longitudinal direction (Y-axis direction). One of the pair of cooling fluid guide portions 318 may be connected to an upper channel 352 of the cooling channel 350 (described later), and the other of the pair of cooling fluid guide portions 318 may be connected to a lower channel 354 of the cooling channel 350 (described later). Specifically, one of the pair of cooling fluid guide portions 318 may be provided at an upper side (+Z-axis direction) in the height direction (Z-axis direction) of the cooling tube 310 to communicate with the upper channel 352 (described later), and the other of the pair of cooling fluid guide portions 318 may be provided at a lower side (-Z-axis direction) in the height direction (Z-axis direction) of the cooling tube 310 to communicate with a lower channel 354 (described later).

[0100] The cooling flow path 350 circulates a cooling fluid for cooling the battery cell 100, and may be provided in the cooling tube 310 and connected to communicate with a cooling fluid inlet / outlet 370, which will be described later.

[0101] Such cooling channels 350 may include an upper channel 352 , a lower channel 354 , and a connecting channel 356 .

[0102] The upper flow passage 352 may be disposed above the cooling tube 310 so as to be provided near the bus bar assembly 200, and may be formed to a predetermined length along the longitudinal direction (Y-axis direction) of the cooling tube 310. The upper flow passage 352 may be connected to communicate with the cooling fluid supply port 374 of the cooling fluid inlet / outlet part 370.

[0103] There may be at least one upper flow passage 352. Hereinafter, in this embodiment, in order to ensure cooling performance, the description will be limited to the case where a plurality of upper flow passages 352 are provided.

[0104] The lower flow passage 354 may be disposed below (in the -Z-axis direction) the cooling tube 310, spaced apart from at least one upper flow passage 352, and may have a predetermined length along the longitudinal direction (in the Y-axis direction) of the cooling tube 310. The lower flow passage 354 may be connected to communicate with the cooling fluid discharge port 376 of the cooling fluid inlet / outlet part 370.

[0105] There may be at least one lower passage 354. In the following, in this embodiment, in order to ensure cooling performance, the description will be limited to the case where a plurality of lower passages 354 are provided.

[0106] The connecting channel 356 may connect at least one upper channel, in this embodiment, a plurality of upper channels 352 , to at least one lower channel, in this embodiment, a plurality of lower channels 354 .

[0107] The connecting passage 356 may be provided at the other end (+Y-axis direction) of the cooling tube 310 opposite to the cooling fluid inlet / outlet 370 so as to maximize the cooling passage 350 .

[0108] In this embodiment, when the cooling fluid circulates in the cooling passage 350, the cooling fluid supplied from the cooling fluid supply port 374 is first supplied to the upper passage 352 located near the bus bar assembly 200, and then flows through the connecting passage 356 and the lower passage 354 toward the cooling fluid discharge port 376.

[0109] As a result, in this embodiment, a cold cooling fluid is preferentially supplied to the area near the busbar assembly 200, which has a relatively high temperature distribution within the battery pack 1, thereby significantly improving the cooling performance of the battery cells 100.

[0110] The cooling fluid inlet / outlet 370 may be connected to the cooling tube 310 so as to communicate with the cooling passage 350 of the cooling tube 310. The cooling fluid inlet / outlet 370 may be exposed to the outside of a side structural unit 400 (described later) and connected to communicate with an external cooling line.

[0111] The cooling fluid inlet / outlet part 370 may be provided on one side (-Y-axis direction) in the longitudinal direction (Y-axis direction) of the battery pack 1. The cooling tube 310 connected to the cooling fluid inlet / outlet part 370 may be formed to a predetermined length from the cooling fluid inlet / outlet part 370 toward the other side (+Y-axis direction) of the battery pack 1 in the longitudinal direction (Y-axis direction) of the battery pack 1.

[0112] The cooling fluid inlet / outlet section 370 may include an outlet section body (a supply port body 371 and an exhaust port body 372 ), a cooling fluid supply port 374 , and a cooling fluid exhaust port 376 .

[0113] The outlet body (supply port body 371, exhaust port body 372) may be connected to one end (-Y axis direction) of the cooling tube 310. The outlet body may include the supply port body 371 and the exhaust port body 372.

[0114] The supply port body 371 covers one end (in the -Y-axis direction) of the cooling tube 310 and may be coupled to an exhaust port body 372, which will be described later. The supply port body 371 may have a supply port through-hole 371a through which a cooling fluid supply port 374, which will be described later, passes. The cooling fluid supply port 374, which will be described later, may pass through the supply port through-hole 371a and communicate with an upper flow passage 352, which will be described later, via the cooling fluid guide portion 318. Specifically, the cooling fluid supply port 374, which will be described later, may communicate with an upper flow passage 352, which will be described later, via a cooling fluid guide portion 318, which is located on the upper side (in the +Z-axis direction) of the cooling fluid guide portion 318 of the cooling tube 310.

[0115] The discharge port body 372 may be coupled to the supply port body 371 on the opposite side of the supply port body 371 across one end (-Y axis direction) of the cooling tube 310, and may 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 hemming.

[0116] The discharge port body 372 may have a discharge port through-hole 372a through which a cooling fluid discharge port 376 (described later) passes. The cooling fluid discharge port 376 (described later) may pass through the discharge port through-hole 372a and communicate with a lower flow passage 354 (described later) via the cooling fluid guide 318. Specifically, the cooling fluid discharge port 376 (described later) may communicate with a lower flow passage 354 (described later) via a cooling fluid guide 318 (described later) located on the lower side (in the −Z-axis direction) of the cooling fluid guides 318 of the cooling tube 310.

[0117] The cooling fluid supply port 374 may be provided in the supply port body 371 of the outlet body (supply port body 371, discharge port body 372) and may be connected to communicate with the upper flow passage 352. Here, the cooling fluid supply port 374 may be caulked to the supply port body 371. The cooling fluid supply port 374 may be connected to communicate with the external cooling line.

[0118] The cooling fluid discharge port 376 may be provided in the discharge port body 372 of the outlet body (supply port body 371, discharge port body 372) and may be connected to communicate with the lower flow passage 354. Here, the cooling fluid discharge port 376 may be caulked to the discharge port body 372. The cooling fluid discharge port 376 may be spaced a predetermined distance from the cooling fluid supply port 374 and may be connected to communicate with the external cooling line.

[0119] 2, the side structural unit 400 is made of a plastic resin material, and can support the battery cells 100, ensure the rigidity of the battery cells 100, and form the side appearance of the battery pack 1.

[0120] The side structural unit 400 will be described in more detail below with reference to the related drawings.

[0121] 15 is a diagram for explaining the side structural unit shown in FIG. 2, and FIG. 16 is a diagram for explaining the main plate of the side structural unit of FIG.

[0122] 15 and 16, the side structural unit 400 supports the battery cells 100, ensures the rigidity of the battery cells 100, and functions as a pack case that forms the outer surface of the battery pack 1 (see FIG. 2) and defines the appearance of the battery pack 1 (see FIG. 2).

[0123] The side structural unit 400 is formed with a predetermined length along the longitudinal direction (Y-axis direction) of the battery pack 1 and can accommodate and support the battery cells 100.

[0124] The side structural unit 400 may include a main plate 410 and an end plate 450 .

[0125] The main plate 410 is formed to a predetermined length along the longitudinal direction (Y-axis direction) of the battery pack 1 and may accommodate the battery cells 100 arranged in two rows along the width direction (X-axis direction) of the battery pack 1. A plurality of such main plates 410 may be provided and arranged at a predetermined distance from each other along the width direction (X-axis direction) of the battery pack 1.

[0126] The plurality of main plates 410 ensures the rigidity of the battery cells 100 and the cooling unit 300, and at the same time, occupies a predetermined space within the battery pack 1 (see FIG. 2), thereby reducing the amount of filling member 500 to be injected, which will be described later. Since the filling member 500 containing a silicone resin, which will be described later, is relatively expensive, reducing the amount of silicone resin to be injected by using the plurality of main plates 410 can further ensure price competitiveness during the manufacture of the battery pack 1.

[0127] Each of the plurality of main plates 410 may include a first cell receiving portion 411 , a second cell receiving portion 412 , an interwing 413 , a bottom rib 415 , a busbar guide protrusion 416 , a cooling unit insertion groove 417 , and a guide step 418 .

[0128] The first cell receiving portion 411 may be provided in front of the main plate 410 (positive X-axis direction) along the longitudinal direction (Y-axis direction) of the main plate 410. The first cell receiving portion 411 may receive a plurality of the battery cells 100 arranged in the longitudinal direction (Y-axis direction) of the battery pack 1. Therefore, a plurality of the first cell receiving portions 411 may be provided in front of the main plate 410 (positive X-axis direction).

[0129] Each of the plurality of first cell accommodating portions 411 may be configured in 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 .

[0130] The second cell receiving portion 412 may be provided at the rear (negative X-axis direction) of the main plate 410 along the longitudinal direction (Y-axis direction) of the main plate 410. The second cell receiving portion 412 may receive a plurality of the battery cells 100 arranged in the longitudinal direction (Y-axis direction) of the battery pack 1. Therefore, a plurality of the second cell receiving portions 412 may be provided at the rear (negative X-axis direction) of the main plate 410.

[0131] Each of the plurality of second cell accommodating portions 412 may be configured in 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 .

[0132] The plurality of second cell accommodating portions 412 may be arranged alternately with the plurality of first cell accommodating portions 411 in the front-rear direction (X-axis direction) of the main plate 410 so as to accommodate a maximum number of battery cells 100, which are cylindrical secondary batteries.

[0133] A plurality of interwings 413 may be provided and protrude along the width direction (X-axis direction) of the main plate 410 so as to separate the plurality of first cell receiving portions 411 and the plurality of second cell receiving portions 412. Specifically, the plurality of interwings 413 may be formed at both the front (+X-axis direction) and rear (-X-axis direction) along the width direction (X-axis direction) of the main plate 410. More specifically, among the plurality of interwings 413, those protruding toward the front (+axis direction) of the main plate 410 may separate the plurality of first cell receiving portions 411, and among the plurality of interwings 413, those protruding toward the rear (-axis direction) of the main plate 410 may separate the plurality of second cell receiving portions 412.

[0134] The bottom rib 415 is provided on the bottom of the main plate 410 and can support the bottom of the battery cell 100 when the battery cell 100 is accommodated in the main plate 410 .

[0135] The bottom rib 415 may be formed to protrude downward (in the −Z-axis direction) from the bottom of the battery cell 100 when the battery cell 100 is accommodated in the main plate 410.

[0136] The bus bar guide protrusion 416 is provided to fix the connecting bus bar unit 230 when assembling the bus bar assembly 200, and is provided on the upper surface of the main plate 410, and at least one bus bar guide protrusion 416 may be provided. Hereinafter, the present embodiment will be described limited to the case where a plurality of bus bar guide protrusions 416 are provided.

[0137] When assembling the busbar assembly 200, the plurality of busbar guide protrusions 416 may be inserted into the guide holes 246 of the busbar cover 240 to guide the correct positioning of the connecting busbar unit 230. Since the connecting busbar unit 230 is fixed by being inserted into or coupled to the plurality of busbar guide protrusions 416, a welding process for electrical connection of the busbar assembly 200 may be performed more stably, and the welding quality during the welding process may be further improved.

[0138] 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). The end of the cooling unit 300 is disposed in the cooling unit insertion groove 417 when the main plate 410 is assembled, thereby allowing for more stable fixation.

[0139] The guide steps 418 may be protruded at a predetermined height from the upper end portions of both sides in the longitudinal direction (Y-axis direction) of the main plate 410. When the assembly of the side structural unit 400 is completed by combining the main plate 410 with an end plate 450 (described later), the guide steps 418 may form the periphery of the side structural unit 400 together with end guide steps 458 of the end plate 450 (described later).

[0140] The end plates 450 may be provided in pairs on both sides of the outermost edge in the width direction (X-axis direction) of the side structural unit 400. The pair of end plates 450 may accommodate and support the battery cells 100 together with the main plate 410 disposed opposite to the pair of end plates 450.

[0141] The pair of end plates 450 may be provided with terminal holes 456 and end guide steps 458 .

[0142] The terminal holes 456 are for receiving the connector terminals 290 and may be provided at one end of the end plate 450 .

[0143] The end guide step 458 may be formed along the upper edge of the end plate 450 and protrude at the same height as the guide step 418. When the assembly of the side structural unit 400 is completed, the end guide step 458 may form the periphery of the side structural unit 400 together with the guide step 418 of the main plate 410.

[0144] Hereinafter, the coupling structure between the battery cell 100 and the cooling unit 300 through the side structure unit 400 will be described in more detail.

[0145] 17 to 20 are diagrams for explaining the connection structure between the battery cell and the cooling unit via the side structure unit of FIG.

[0146] 17 to 20, first, the cooling tubes 310 of the cooling unit 300 are sandwiched between the battery cells 100 arranged in two rows in the width direction (X-axis direction) of the battery pack 1 (see FIG. 2) among the battery cells 100. In this manner, in the front-rear direction (X-axis direction) of the battery cells 100 between which the cooling tubes 310 are sandwiched, the side structural units 400 can accommodate the opposing battery cells 100.

[0147] Specifically, the end plate 450, the battery cell 100, the cooling tube 310, the battery cell 100, and the main plate 410 may be arranged at the outermost position in the width direction (X-axis direction) of the battery pack 1 (see FIG. 2 ), and then the battery cell 100, the cooling tube 310, the battery cell 100, and the main plate 410 may be arranged and coupled again in this order. Thereafter, the end plate 450 at the outermost position on the opposite side in the width direction (X-axis direction) of the battery pack 1 (see FIG. 2 ) is finally arranged and coupled to complete the coupling of the side structural unit 400, and the battery cell 100 and the cooling unit 300 may be housed within the side structural unit 400.

[0148] Here, both ends of the cooling unit 300 are inserted into the cooling unit insertion grooves 417 when the main plates 410 are joined together and when the main plate 410 is joined to the end plate 450, thereby preventing interference with the cooling unit 300 and more stably fixing the cooling unit 300.

[0149] When the main plates 410 are coupled together, the opposing thick portion 410a and thin portion 410b may have the following relationship. As will be described later, a contact angle θ between the battery cell 100 and the cooling tube 310 may be approximately 60°. Here, a length W1 of the thick portion 410a of the main plate 410 may be at least equal to or shorter than a diameter of the battery cell 100, and a length W2 of the thin portion 410b of the main plate 410 may be at least equal to or shorter than a radius of the battery cell 100.

[0150] Consequently, the length W1 of the thick portion 410a of the main plate 410 cannot be longer than the diameter of the battery cell 100, and the length W2 of the thin portion 410b of the main plate 410 cannot be longer than the radius of the battery cell 100.

[0151] Specifically, in this embodiment, when the diameter of the battery cell 100 is 46 mm, the length W1 of the thick portion 410a of the main plate 410 may be at least 46 mm or less than 46 mm. For example, the length W1 of the thick portion 410a of the main plate 410 may be in the range of 44 mm to 46 mm. Furthermore, the length W2 of the thin portion 410b of the main plate 410 may be at least 23 mm or less than 23 mm. For example, the length W2 of the thin portion 410b of the main plate 410 may be in the range of 21 mm to 23 mm.

[0152] Meanwhile, the cooling unit insertion groove 417 may be formed in the thin portion 410b of the thick portion 410a and thin portion 410b of the main plate 410. Here, the cooling unit insertion groove 417 receives the end of the cooling tube 310 and may be formed to have a thickness at least equal to the thickness of the cooling tube 310 or greater than the thickness of the cooling tube 310 in consideration of assembly tolerances, etc.

[0153] 20 , the thick portion 410a and the thin portion 410b of the main plate 410 may be coupled to each other to further enhance the coupling strength of the main plate 410. Specifically, the thick portion 410a and the thin portion 410b of the main plate 410 may be fitted to each other at their opposing portions. To this end, a fitting groove 414a of a predetermined depth may be formed in the thick portion 410a of the main plate 410, and a fitting protrusion 414b that fits into the fitting groove 414a may be formed in the thin portion 410b of the main plate 410. However, this is merely an example, and it goes without saying that the fitting groove 414a may be formed in the thin portion 410b of the main plate 410, and the fitting protrusion 414b may be formed in the thick portion 410a of the main plate 410.

[0154] In addition, a cooling fluid inlet / outlet 370 provided at one end of the cooling unit 300 may be disposed to protrude outward from the side structural unit 400 for connection to an external cooling line or the like.

[0155] The side structural unit 400 according to the present embodiment can form a side outer structure of the battery pack 1 (see FIG. 2 ) while accommodating the battery cells 100 and the cooling unit 300 through the connection between the main plate 410 and the end plate 450. That is, the side structural unit 400 can function as a pack case that forms the exterior of the battery pack 1.

[0156] As a result, the battery pack 1 (see FIG. 1) according to the present embodiment can omit a separate additional pack case or pack housing structure through the side structural unit 400, thereby reducing manufacturing costs and further increasing the energy density by reducing the overall size of the battery pack 1.

[0157] 21 and 22 are diagrams for explaining the positional relationship between the battery cells and the cooling unit through the side structure unit of FIG.

[0158] 21 and 22, the battery cell 100, the cooling unit 300, and the side structural unit 400 may be configured to be arranged at a predetermined distance ratio that is already set for mutual close contact.

[0159] Specifically, the distance A between the center of the battery cell 100 provided in the first cell receiving portion 411 of the main plate 410 and the center of the battery cell 100 provided in the second cell receiving portion 412 is a distance set for close contact with the main plate 410 and can be changed depending on the thickness of the main plate 410.

[0160] The distance B between the centers of adjacent battery cells 100 in contact with one side of the cooling tube 310 is a distance set to set the contact angle θ between the battery cell 100 and the cooling tube 310 to a predetermined angle, for example, 60°, and can be changed in conjunction with the distance C described below.

[0161] Furthermore, the distance C between the centers of the battery cells 100 arranged opposite each other across the cooling tube 310 is a distance that reflects the thickness of the cooling tube 310 and may be determined in conjunction with the distance B between the centers of the adjacent battery cells 100 that contact one side of the cooling tube 310.

[0162] The distances A to C may be set as optimal distances for closer contact between the battery cell 100 and the cooling tube 310 and the side structural unit 400. Specifically, the optimal distances may be determined in consideration of the diameter of the battery cell 100, the thickness of the cooling tube 310, and the contact angle θ between the battery cell 100 and the cooling tube 310. For example, in the present embodiment, the diameter of the battery cell 100 may be 46 mm, and the thickness of the cooling tube 310 may be 2.5 mm.

[0163] Meanwhile, the optimum distance may refer to a case where the contact angle θ between the battery cell 100 and the cooling tube 310 is 60° or an angle close to that. The reason for setting the contact angle θ to 60° is that if the contact angle θ is greater than 60°, the cooling performance can be improved, but the spacing between the battery cells 100 becomes wider, resulting in a problem of the overall battery pack 1 becoming larger. Furthermore, as the contact angle becomes larger, the degree of curvature of the cooling tube 310 also increases, which may increase fluid pressure and reduce the cooling flow. Also, if the contact angle is less than 60°, the cooling area decreases, resulting in a problem of reduced cooling efficiency.

[0164] In consideration of the above, it is desirable that the contact angle θ be within a range of approximately ±1.5° with 60° as the reference. The dimensions of the distance B and the distance C can be set to reflect this contact angle θ. Specifically, the dimensions of the distance B and the distance C can be set so that the contact angle θ is in the range of 58.5° to 61.5°.

[0165] As described above, in this embodiment, the optimal distances A to C may be determined in consideration of the diameter of the battery cell 100, the thickness of the cooling tube 310, and the contact angle θ between the battery cell 100 and the cooling tube 310.

[0166] Specifically, in this embodiment, the optimal distances A to C taking all of these factors into consideration are as follows: The distance A between the center of the battery cell 100 provided in the first cell receiving portion 411 of the main plate 410 and the center of the battery cell 100 provided in the second cell receiving portion 412 may be 47.5 mm, which is the optimal distance for optimal contact with the main plate 410. Also, in this embodiment, the distance B between the centers of adjacent battery cells 100 in contact with one surface of the cooling tube 310 may be 49 mm, which is the optimal distance for setting the optimal contact angle θ. Furthermore, in this embodiment, the distance C between the centers of battery cells 100 arranged opposite each other across the cooling tube 310 may be 49.2 mm, which is the optimal distance that reflects the thickness of the cooling tube 310.

[0167] Meanwhile, the pitch P1 between the contact portions of the cooling tubes 310 may be linked to the spacing between the battery cells 100, and in this embodiment, the pitch P1 may be 49 mm.

[0168] The distance d1 between the battery cells 100 disposed diagonally opposite each other across the cooling tube 310 may be determined depending on the assemblability of the battery cells 100 and the cooling tube 310, the thickness of the cooling tube 310, and the thickness of a coating or glue for bonding between the cooling tube 310 and the battery cells 100. For example, the distance d1 may be determined by taking into consideration the thickness of the cooling tube 310 as well as the thickness of the coating and glue applied to both sides of the cooling tube 310. Specifically, when the thickness of the cooling tube 310 is 2.5 mm, the thickness of the coating (e.g., epoxy coating) is a maximum of 0.25 mm, and the thickness of the glue is 0.1 mm, the distance d1 may be 3.2 mm by taking into consideration the thickness of the cooling tube 310 (2.5 mm), the thickness of the coating applied to both sides of the cooling tube 310 (2*0.25 mm), and the thickness of the glue (2*0.1 mm).

[0169] Meanwhile, the end of the interwing 413 provided between the first cell receiving portion 411 and the second cell receiving portion 412 of the main plate 410 may be formed shorter than one side of the battery cell 100 that contacts the cooling tube 310 to prevent interference with the opposing cooling tube 310.

[0170] For example, the distance P2 between the end of the interwing 413 of the main plate 410 and the center of the battery cell 100 may be determined to be a distance that can avoid interference with the cooling tube 310, taking into consideration the diameter of the battery cell 100 and the thickness of the cooling tube 310. For example, the distance P2 between the end of the interwing 413 and the center of the battery cell 100 may be 15 mm.

[0171] Meanwhile, the thicknesses of the first cell receiving portion 411 and the second cell receiving portion 412 of the main plate 410 may be determined in consideration of assembly with the battery cells 100 .

[0172] Specifically, the thicknesses of the first cell accommodating portion 411 and the second cell accommodating portion 412 of the main plate 410 are determined in consideration of the distance d2 between the battery cells 100, and the minimum thickness t of the first cell accommodating portion 411 and the second cell accommodating portion 412 may be approximately half of the distance d2 between the battery cells 100. For example, in the present embodiment, the distance d2 between the battery cells 100 is 1.5 mm, and the minimum thickness t of the first cell accommodating portion 411 and the second cell accommodating portion 412 may be approximately 0.75 mm, specifically 0.7 mm.

[0173] As a result, when the battery cell 100 is accommodated in the first cell accommodating portion 411 and the second cell accommodating portion 412 of the main plate 410, a predetermined gap space g may be formed between the first cell accommodating portion 411 and the second cell accommodating portion 412.

[0174] When the battery cell 100 is accommodated in each cell accommodating portion (the first cell accommodating portion 411, the second cell accommodating portion 412), the gap space g may be formed in the remaining area excluding the innermost area of ​​the concave shape of the first cell accommodating portion 411 and the second cell accommodating portion 412. Here, the innermost area of ​​the concave shape of the first cell accommodating portion 411 and the second cell accommodating portion 412 may refer to an area disposed on the opposite side of the protruding portion of the interwing 413 on the inner surface of the concave shape of the first cell accommodating portion 411 and the second cell accommodating portion 412.

[0175] Accordingly, when the battery cell 100 is received in the first cell receiving portion 411 and the second cell receiving portion 412 of the main plate 410, the battery cell 100 may contact the inner surfaces of the first cell receiving portion 411 and the second cell receiving portion 412 only in the innermost region of the concave shape, and may be spaced apart by the gap space g from the other inner surfaces of the first cell receiving portion 411 and the second cell receiving portion 412. Meanwhile, an adhesive or the like for adhering to the battery cell 100 may be applied to the innermost region of the concave shape that contacts the battery cell 100.

[0176] In addition, when the battery cell 100 is received in the first cell receiving portion 411 and the second cell receiving portion 412 of the main plate 410, the interwing 413 may also be spaced apart from the battery cell 100 by the gap space g.

[0177] In this embodiment, when assembling the battery cell 100 and the main plate 410, specifically when accommodating the battery cell 100 in the first cell accommodating portion 411 and the second cell accommodating portion 412, such gap space g can prevent interference or collision between the battery cell 100 and the first cell accommodating portion 411, the second cell accommodating portion 412, and the interwing 413, thereby significantly improving assembly efficiency.

[0178] Furthermore, in this embodiment, the assembly tolerances of the members can be absorbed to a large extent through the gap space g, and problems such as incorrect assembly or assembly defects due to the assembly tolerances can be significantly reduced.

[0179] Furthermore, the gap space g may be filled with a filler 500, which will be described later. In this manner, in the present embodiment, since the gap space g is filled with the filler 500, the amount of filler 500 between the battery cells 100 can be further ensured.

[0180] Therefore, in this embodiment, the battery cell 100 can be more stably supported in the first cell accommodating portion 411 and the second cell accommodating portion 412 of the main plate 410 through the filling member 500 filled in the gap space g.

[0181] Furthermore, through the filling member 500 filled in the gap space g, when an event such as thermal runaway of the battery cell 100 occurs, current flow to the adjacent battery cell 100 or thermal runaway can be more effectively prevented.

[0182] 23 to 25 are diagrams for explaining the contact structure between the battery cell of FIG. 22 and the cooling unit.

[0183] 23 to 25, the outer circumferential surface of the battery cell 100 may contact the cooling tube 310 of the cooling unit 300 in a height direction (Z-axis direction). Here, the contact area A2 between the battery cell 100 and the cooling tube 310 may be determined depending on the contact angle θ between the battery cell 100 and the cooling tube 310, the height h2 of the cooling tube 310, etc., in consideration of ease of assembly and optimal cooling performance.

[0184] In this embodiment, the contact area A2 of the cooling tube 310 of the battery cell 100 may be in the range of about 14% to 15% of the entire area A1 of the outer circumferential surface of the battery cell 100.

[0185] For example, in this embodiment, the radius R of the battery cell 100 may be 23 mm, the height h1 may be 80 mm, the height h2 of the cooling tube 310 may be 70 mm, 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 circumferential surface of the battery cell 100 may be determined as the product of the circumferential length (2πR), i.e., the base length (2πR), and the outer edge height h1 of the battery cell 100. Thus, the total area A1 of the outer circumferential surface of the battery cell 100 is 0.368πm 2 If we replace π with 3.14, we get about 1.16m 2 In addition, the contact area A2 of the cooling tube 310 of the battery cell 100 may be determined as the product of the arc length l according to the contact angle θ and the height h2 of the cooling tube 310. Here, the arc length l may be derived from Equation 1 below.

[0186]

number

[0187] As a result, the arc length l is approximately 0.077πm, which is approximately 0.242m when π is replaced by 3.14. Therefore, the contact area A2 of the cooling tube 310 of the battery cell 100 is approximately 0.169m, which is calculated by multiplying the arc length l by the height h2 of the cooling tube 310, which is 70mm. 2 It could be.

[0188] As described above, in this embodiment, the contact area A2 of the cooling tube 310 of the battery cell 100 may be set to a range of approximately 14.5% of the total area A1 of the outer circumferential surface of the battery cell 100 to ensure optimal cooling performance and also ensure ease of assembly with the cooling tube 310.

[0189] Furthermore, in this embodiment, the height h1 of the battery cell 100 may be formed to be greater than the height h2 of the cooling tube 310 so as to avoid contact between the cooling tube 310 and the connecting busbar unit 230 and to prevent the possibility of a short circuit between the cooling tube 310 and the connecting busbar unit 230.

[0190] Figure 26 is a diagram showing the bottom of the side structural unit of Figure 15 when it is connected to the battery cell, Figure 27 is an enlarged bottom view of the main parts of the side structural unit of Figure 26, and Figure 28 is a side view of the main parts of the side structural unit of Figure 26.

[0191] 26 to 28, the bottom rib 415 of the side structural unit 400 may be provided to protrude further downward (in the −Z-axis direction) than the bottom of the battery cell 100 so as not to interfere with the vent portion 31 of the battery cell 100. As a result, when gas is discharged through the vent portion 31 due to overheating of the battery cell 100, the gas can be discharged more quickly without interference from the bottom rib 415.

[0192] Furthermore, the bottom rib 415 is formed to cover one side of the bottom of the battery cell 100, and can more firmly fix the battery cell 100 within the side structural unit 400 when the battery cell 100 is inserted into the side structural unit 400.

[0193] As a result, the height h3 of the side structural unit 400 may be configured to be greater than the height of the battery cell 100 so as to cover all of the upper and lower sides of the battery cell 100 in the vertical direction (Z-axis direction). For example, in the present embodiment, since the height of the battery cell 100 is 80 mm, the height h3 of the side structural unit 400 may be greater than the height h3 of the battery cell 100 on all of the upper and lower sides of the battery cell 100.

[0194] Furthermore, the height h3 of the side structural unit 400 may be set to a height that covers the thickness of the bus bar assembly 200 and the filler member 500 placed on the battery cell 100. Specifically, taking all of these factors into consideration, the height h3 of the side structural unit 400 may be set to a range of approximately 85 mm to 95 mm. More specifically, the height h3 of the side structural unit 400 may be 90.3 mm, or approximately 90 mm.

[0195] 2, the filling member 500 may be filled in a 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. Meanwhile, in FIG. 2, the filling member 500 is shown by a dotted line in the shape of a rectangular parallelepiped for ease of understanding, but the filling member 500 may be filled in the entire space between the cooling unit 300 and the plurality of battery cells 100.

[0196] The filling member 500 covers the upper and lower sides of the battery pack 1 (see FIG. 2), and thus can form a pack case structure of the battery pack 1 together with the side structural unit 400.

[0197] In addition, the filling member 500 may more stably fix the plurality of battery cells 100 and at the same time, increase the heat dissipation efficiency of the plurality of battery cells 100, thereby further improving the cooling performance of the battery cells 100.

[0198] The filling member 500 may include a potting resin. The potting resin may be formed by injecting a loose resin material into the battery cells 100 and hardening it. Here, the injection of the resin material may be performed at room temperature of about 15°C to 25°C to prevent thermal damage to the battery cells 100.

[0199] Specifically, the filling member 500 may include a silicone resin. However, without being limited thereto, the filling member 500 may include other resin materials other than the silicone resin that can improve the fixing and heat dissipation efficiency of the battery cells 100.

[0200] More specifically, the filling member 500 covers the portion of the battery cell 100 that is not in contact with the cooling tube 310, thereby guiding the thermal balance of the battery cell 100 and preventing uneven cooling of the battery cell 100, thereby preventing local deterioration of the battery cell 100. In addition, by preventing local deterioration of the battery cell 100, the safety of the battery cell 100 can be significantly improved.

[0201] In addition, the filling member 500 may serve as an insulator that prevents current from flowing to an adjacent battery cell 100 when at least one specific battery cell 100 among the plurality of battery cells 100 is damaged due to an abnormal condition.

[0202] In addition, the filling member 500 may include a material having high specific heat performance. Accordingly, the filling member 500 increases the thermal mass, thereby delaying a temperature rise of the battery cell 100 even in a situation such as rapid charging and discharging of the battery cell 100, thereby preventing a rapid temperature rise of the battery cell 100.

[0203] The filler member 500 may include glass bubbles, which may reduce the specific gravity of the filler member 500 and increase the energy density per weight.

[0204] In addition, the filling member 500 may include a material having high heat resistance. Thus, when a thermal event such as overheating occurs in at least one specific battery cell 100 among the plurality of battery cells 100, the filling member 500 can effectively prevent thermal runaway from occurring in the adjacent battery cells.

[0205] In addition, the filling member 500 may include a material having high flame retardancy, thereby minimizing the risk of fire when a thermal event such as overheating occurs in at least one specific battery cell 100 among the plurality of battery cells 100.

[0206] The filling member 500 may be filled in the bus bar assembly 200 in addition to the battery cell 100. Specifically, the filling member 500 may be filled in the bus bar assembly 200 so as to cover an upper side of the bus bar assembly 200.

[0207] Here, the filling member 500 may be continuously filled between the bus bar assembly 200 and the battery cell 100 in the vertical direction (Z-axis direction) of the battery cell 100 without any disconnection or separation space between the bus bar assembly 200 and the battery cell 100.

[0208] As described above, the filling member 500 according to the present embodiment is continuously filled between the battery cells 100 and the bus bar assemblies 200 without any discontinuity, thereby achieving uniform heat dispersion without any variation in heat dispersion in the region between the battery cells 100 and the bus bar assemblies 200, and significantly improving the cooling performance of the battery pack 1.

[0209] Furthermore, the filling member 500 may be filled in a portion other than the outer surface of the side structural unit 400. Here, the filling member 500 may be continuously filled in the battery cells 100, the bus bar assemblies 200, and the side structural unit 400 without any breaks. This may further improve the cooling performance of the battery pack 1.

[0210] The formation of the pack case structure by injecting the filling member 500 will be described in more detail below.

[0211] 29 to 31 are diagrams for explaining the formation of a pack case structure by injecting a filling material into the battery pack shown in FIG.

[0212] 29 to 31, an operator may use a resin injection device I to inject and apply the filling member 500 containing the silicone resin, thereby forming upper and lower pack case structures of the battery pack 1 (see FIG. 2) through the filling member 500 containing the resin material. Specifically, the filling member 500 may be filled up to a protruding height h4 of the bottom rib 415 while covering the upper side of the bus bar assembly 200 on the upper side (+Z-axis direction) of the battery pack 1 and covering the bottom of the battery cell 100 on the lower side (-Z-axis direction) of the battery pack 1. Here, the protruding height h4 of the bottom rib 415 may be designed to a predetermined height taking into consideration the injection amount of the filling member 500.

[0213] During the injection and application process of the filling member 500 using the resin injection device I, an injection guider S may be provided at the bottom of the side structural unit 400 to prevent resin from flowing downward (in the -Z-axis direction) when the filling member 500 is injected. The injection guider S may be made of a Teflon® material or the like for easy detachment after the filling member 500 has hardened.

[0214] During the injection and application process of the filling member 500, the side structural unit 400, together with the injection guider S, may serve as a formwork that supports the battery cell 100 and the cooling unit 300 and prevents resin from leaking out.

[0215] As a result, in this embodiment, the side structure unit 400 eliminates the need for an additional injection guide jig structure in the side direction during the injection and application process of the filling material 500, thereby significantly improving work efficiency while reducing manufacturing costs.

[0216] Furthermore, the side structure unit 400 guides the connecting busbar unit 230 in a fixed position through the busbar guide protrusions 416 inserted into the connecting busbar unit 230, thereby effectively preventing twisting or misalignment of the connecting busbar unit 230 that may occur when the filling material 500 is injected.

[0217] In addition, the guide step 418 and the end guide step 458 formed on the upper edge of the side structural unit 400 increase the injection accuracy of the filler 500 when injecting the filler 500, making it easier to inject the filler 500 so that it more reliably covers the bus bar assembly 200, and effectively preventing the filler 500 from overflowing.

[0218] Here, the side structural unit 400 exposes components connected to external devices such as the interconnection board 260, connector terminals 290, and cooling fluid inlet / outlet port 370 to the outside, so there are no problems such as interference with these components when injecting or applying the filling material 500.

[0219] As a result, in this embodiment, the pack case structure of the battery pack 1 (see FIG. 1) is formed through the side structural unit 400 and the filling member 500, which simplifies the assembly process of the battery pack 1 compared to the conventional case in which the pack case structure is formed as a complex assembly of multiple plates, significantly reducing manufacturing costs and ensuring price competitiveness.

[0220] Furthermore, according to the present embodiment, the pack case structure formed by the side structural unit 400 and the filling member 500 can reduce the size of the entire battery pack 1 and significantly increase the energy density, compared to a conventional pack case structure provided as a cell frame structure including an assembly of multiple plates.

[0221] FIG. 32 is a view for explaining a battery pack according to another embodiment of the present invention, and FIG. 33 is an exploded perspective view of the battery pack of FIG.

[0222] Since the battery pack 2 according to this embodiment is similar to the battery pack 1 according to the above-described embodiment, the description of the configurations that are substantially the same as or similar to those of the above-described embodiment will be omitted, and the following description will focus on the differences from the above-described embodiment.

[0223] 32 and 33, the battery pack 2 may include a plurality of battery cells 100, a busbar assembly 205, a cooling unit 300, a side structural unit 405, and a filling member 500.

[0224] The plurality of battery cells 100, the cooling unit 300, and the filling member 500 are substantially the same as or similar to those in the above-described embodiments, and therefore, overlapping descriptions will be omitted.

[0225] The busbar assembly 205 will be described in more detail below with reference to the related drawings.

[0226] FIG. 34 is a diagram illustrating the busbar assembly of the battery pack shown in FIG. 33, and FIG. 35 is a diagram illustrating the high-voltage busbar unit of the busbar assembly shown in FIG.

[0227] 34, 35 and 33, the busbar assembly 205 may include a main busbar unit 210, a connecting busbar unit 230, an interconnection board 260, a high-voltage busbar unit (high-voltage line member 270, connector mounting member 280), and a connector terminal 290.

[0228] The main bus bar unit 210, the connecting bus bar unit 230, and the interconnection board 260 are substantially the same as or similar to those in the above-described embodiment, and therefore, a duplicated description will be omitted.

[0229] The high-voltage busbar unit (high-voltage line member 270, connector mounting member 280) is intended to ensure the electrical safety of the busbar assembly 200, and may be formed to be thicker than the main busbar unit 210. For example, in this embodiment, the main busbar unit 210 has a thickness of 0.4 mm, and the high-voltage busbar unit (high-voltage line member 270, connector mounting member 280) has a thickness of 4 mm, which is thicker than the main busbar unit 210.

[0230] Such a high voltage busbar unit may include a high voltage line member 270 and a connector mounting member 280 .

[0231] The high-voltage line member 270 may be disposed at the bottom of the main busbar unit 210 and configured to have a predetermined length for stable current flow. The high-voltage line member 270 may be attached to both ends of a main plate 410 of a side structural unit 405 (to be described later) in the width direction (X-axis direction) of the battery pack 2.

[0232] Here, the high-voltage line members 270 may be located at both ends of the main plate 410. Also, the high-voltage line members 270 may be elastically fitted to both ends of the main plate 410. That is, the high-voltage line members 270 may include a material having a predetermined elasticity, and may be elastically coupled to both ends 270 of the main plate 410 and then press against both ends of the main plate 410. By attaching both ends of the main plate 410 to the high-voltage line members 270, the coupling stability between the main plates 410 of the side structural units 405 may be further improved.

[0233] The high voltage line member 270 may be provided in plural numbers depending on the number and capacity of the battery cells 100 of the battery pack 2. That is, the number of the high voltage line members 270 may vary depending on the number and capacity of the battery cells 100.

[0234] Such high voltage line member 270 will be described in more detail below.

[0235] The high voltage line member 270 may include a first high voltage line portion (first voltage line portion) 271 , a second high voltage line portion (second voltage line portion) 273 , and a connecting line portion 275 .

[0236] The first high-voltage line portion 271 may be formed to a predetermined length and may be placed on the main plate 410 so as to be disposed at the bottom of the main bus bar unit 210. Here, the first high-voltage line portion 271 may be formed to be thicker 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 receiving portion 419a of the main plate 410, which will be described later.

[0237] 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 located at the bottom of the main plate 410. The second high voltage line part 273 may be formed to 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.

[0238] The connecting line portion 275 connects the first high voltage line portion 271 and the second high voltage line portion 273 and may be disposed on both sides of the main plate 410 in the height direction (Z-axis direction) of the main plate 410. The connecting line portion 275 is integrally formed with the first high voltage line portion 271 and the second high voltage line portion 273 and may form the current path together with the first high voltage line portion 271 and the second high voltage line portion 273.

[0239] In this embodiment, one of the first high voltage line section 271 and the second high voltage line section 273 may include a disconnection section that allows current to flow from the first high voltage line section 271 to the second high voltage line section 273 or vice versa via the connecting line section 275.

[0240] A plurality of such connection line portions 275 may be provided. The connection line portions 275 may be arranged at predetermined distances from each other in the width direction (X-axis direction) of the battery pack 2. Furthermore, the connection line portions 275 may be arranged 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.

[0241] The connector mounting members 280 may be provided in pairs. The pair of connector mounting members 280 may be disposed between the high-voltage line members 270 and attached to a pair of end plates 450 (see FIG. 34 ) of a side structural unit 405, which will be described later.

[0242] Such a pair of connector fittings 280 may include a high voltage line portion 281 and a connector mating portion 285 .

[0243] The high-voltage line portion 281 may be formed to a predetermined length and placed on the end plate 450 so as 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 accommodating portion 459 of the end plate 450, which will be described later. An upper portion 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.

[0244] The connector connection portion 285 may extend from the high-voltage line portion 281 and be disposed on a side surface along the height direction (Z-axis direction) of the end plate 450. A connector terminal 290, which will be described later, may be attached to the connector connection portion 285.

[0245] The connector terminals 290 are provided in pairs and may be connected to the connector mounting member 280. Specifically, the pair of connector terminals 290 may be attached to the connector coupling portions 285 of the respective connector mounting members 280. Such a pair of connector terminals 290 may be attached to a pair of end plates 450, which will be described later, in a state where they are connected to the connector mounting member 280.

[0246] In this embodiment, the high-voltage busbar unit (high-voltage line member 270, connector mounting member 280) guides a stable current flow in the battery pack 2, thereby improving the electrical safety of the battery pack 2 and further improving efficiency during charging and discharging.

[0247] Figure 36 is a diagram for explaining the side structural unit of the battery pack shown in Figure 33, Figure 37 is a diagram for explaining the main plate of the side structural unit shown in Figure 36, Figure 38 is a diagram for explaining the positional relationship between the battery cell and the cooling unit through the side structural unit of Figure 36, and Figures 39 to 42 are diagrams for explaining the mounting structure of the side structural unit of Figure 36 and the high-voltage busbar unit.

[0248] 36 to 42 and 33, the side structural unit 405 may include a plurality of main plates 410 and a pair of end plates 450.

[0249] Each of the multiple main plates 410 may include a first cell accommodating portion 411, a second cell accommodating portion 412, an interwing 413, a bottom rib 415, a busbar guide protrusion 416, a cooling unit insertion groove 417, and a high-voltage line component accommodating portion (a first line accommodating portion 419a, a second line accommodating portion 419b).

[0250] The first cell receiving portion 411, the second cell receiving portion 412, the interwing 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 above-described embodiments, so overlapping descriptions will be omitted.

[0251] The high-voltage line member accommodating portions (first line accommodating portion 419a, second line accommodating portion 419b) may be formed at both ends along the longitudinal direction (Y-axis direction) of the main plate 410. 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 in these high-voltage line member accommodating portions (first line accommodating portion 419a, second line accommodating portion 419b).

[0252] The high voltage line member housing may include a first line housing 419a and a second line housing 419b.

[0253] The first line accommodating portion 419a accommodates the first high-voltage line portion 271 and may be formed at the edge of the upper end (+Z-axis direction) of both ends along the longitudinal direction (Y-axis direction) of the main plate 410. The first line accommodating portion 419a may be formed with a step of a predetermined depth to prevent the first high-voltage line portion 271 from protruding upward (+Z-axis direction) of the battery pack 2 when accommodating the first high-voltage line portion 271. Here, the predetermined depth may be at least equal to the thickness of the first high-voltage line portion 271.

[0254] The second line accommodating portion 419b accommodates the second high-voltage line portion 273 and may be formed at the edge of the lower end (-Z-axis direction) of both ends along the longitudinal direction (Y-axis direction) of the main plate 410. The second line accommodating portion 419b may be formed with a step of a predetermined depth to prevent the second high-voltage line portion 273 from protruding downward (-Z-axis direction) of the battery pack 2 when accommodating the second high-voltage line portion 273. Here, the predetermined depth may be at least equal to the thickness of the second high-voltage line portion 273.

[0255] The pair of end plates 450 may include terminal holes 456, end guide steps 458, and connector mounting member receiving portions 459.

[0256] The terminal hole 456 and the end guide step 458 are similar to those in the above embodiment, and therefore, a duplicated description will be omitted.

[0257] The connector mounting member receiving portion 459 receives the high voltage line portion 281 and may be formed on the edge of the upper end (+Z-axis direction) of both ends along the longitudinal direction (Y-axis direction) of the end plate 450. The connector mounting member receiving portion 459 may be formed with a step of a predetermined depth to prevent the high voltage line portion 281 from protruding upward (+Z-axis direction) of the battery pack 2 when receiving the high voltage line portion 281. Here, the predetermined depth may be at least equal to the thickness of the high voltage line portion 281.

[0258] Furthermore, the connector mounting member accommodating portion 459 may accommodate a portion of the first high-voltage line portion 271 placed in the first line accommodating portion 419a of the main plate 410 adjacent to the end plate 450 on the side opposite to where the connector terminal 290 is arranged. Therefore, the connector mounting member accommodating portion 459 may be disposed on the same line as the first line accommodating portion 419a in the width direction (X-axis direction) of the battery pack 2.

[0259] 43 and 44 are diagrams for explaining the injection of the filling material into the battery pack of FIG.

[0260] Referring to Figures 43 and 44, a worker or the like can form the pack case structure of the upper and lower parts of the battery pack 2 (see Figure 31) by using a resin injection device I and an injection guide S to inject and apply a filling member 500 provided as the silicone resin.

[0261] In this embodiment, the filling member 500 may be filled on the upper side (+Z-axis direction) of the battery pack 2 so as to cover a portion of the main busbar unit 210 and the connecting busbar unit 230 of the busbar assembly 200.

[0262] Here, the filling member 500 may be filled on the upper side (+Z-axis direction) of the main busbar unit 210 and the connecting busbar unit 230, which are placed on the upper side (+Z-axis direction) of the side structure unit 400, to cover only the electrode connection portions of the battery cells 100 that are electrically connected to the main busbar unit 210 and the connecting busbar unit 230. That is, the filling member 500 may be filled to a height that covers only the electrode connection portions of the main busbar unit 210 and the connecting busbar unit 230 that are bent downward (in the -Z-axis direction) for electrical connection.

[0263] Specifically, the filling member 500 may be filled to an extent that it covers only the positive busbar hole 242 and the negative busbar hole 244 of the connecting busbar unit 230. More specifically, the filling member 500 may be filled until it is aligned with the horizontal portion of the main busbar unit 210 and the horizontal portion of the busbar cover 240. Thus, after the filling of the filling member 500 is completed, the horizontal portion of the main busbar unit 210 and the busbar cover 240 of the connecting busbar unit 230 may be partially exposed on the upper surface (+Z-axis direction) of the battery pack 2.

[0264] As described above, in the present embodiment, the filling member 500 covers only the electrode connection portions of the battery cells 100 that are electrically connected to the main busbar unit 210 and the connecting busbar unit 230 of the busbar assembly 200 on the upper surface (+Z-axis direction) of the battery pack 2, thereby optimizing the application amount of the filling member 500 provided as the silicone resin and effectively ensuring the safety of the electrical connection.

[0265] FIG. 45 is a diagram illustrating a vehicle according to another embodiment of the present invention.

[0266] Referring to FIG. 45, the vehicle V may be an electric vehicle or a hybrid vehicle and may include at least one battery pack 1, 2 of the above-described embodiments as an energy source.

[0267] In this embodiment, the battery packs 1 and 2 are provided in a compact structure with high energy density, and therefore, when mounted on the automobile V, a modular structure of the plurality of battery packs 1 and 2 can be easily realized, and a relatively high degree of freedom in mounting can be ensured even in various shapes of interior spaces of the automobile V. That is, in this embodiment, at least one of the battery packs 1 and 2 can be provided as a battery pack case structure that can easily be realized as a modular structure and has a high degree of mounting freedom.

[0268] In addition, the longitudinal direction of at least one battery pack 1, 2 may be arranged perpendicular to the longitudinal direction of the vehicle V so that the side structural unit 400 can protect the plurality of battery cells 100 during front and rear collisions of the vehicle V.

[0269] Through the various embodiments described above, it is possible to provide battery packs 1 and 2 that can improve energy density and ensure rigidity, and a vehicle V including the battery packs.

[0270] Furthermore, through the various embodiments described above, it is possible to provide battery packs 1 and 2 and a vehicle V including the same that can improve price competitiveness and manufacturing efficiency.

[0271] Furthermore, through the various embodiments described above, it is possible to provide battery packs 1 and 2 with improved cooling performance, and a vehicle V including the same.

[0272] Although the preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the specific embodiments described above. Various modifications can be made by a person skilled in the art to which the present invention pertains without departing from the gist of the present invention as claimed in the claims, and such modifications should not be understood separately from the technical ideas and prospects of the present invention.

[0273] 1 battery pack 2 battery packs 10 Electrode assembly 11 First electrode tab 12 Second electrode tab 20 Battery can 21 Beading Section 22 Crimping section 30 Cap Plate 31 Vent section 40 1st electrode terminal 41 Exposed terminal section 42 Insertion terminal part 50 Insulation gasket 51 Exposed part 52 Insertion section 60 Upper current collecting plate 70 Insulation Plate 80 Lower current collecting plate 90 Sealing Gasket 100 battery cells 200 Busbar Assembly 205 Busbar Assembly 210 Main busbar unit 230 Connecting busbar unit 240 Busbar cover 242 Positive busbar hole 244 Negative busbar hole 246 Guide hole 250 Subbasbar 252 Busbar Bridge 254 Positive electrode connection part 256 Negative electrode connection part 260 Interconnection Board 270 High-voltage line components 271 First High Voltage Line Section (First Voltage Line Section) 273 Second High Voltage Line Section (Second Voltage Line Section) 275 Connecting line section 280 Connector mounting member 281 High voltage line section 285 Connector joint 290 Connector terminal 300 Cooling Unit 310 Cooling tube 312 Convex part 316 Recess 318 Cooling fluid guide 350 Cooling Channel 352 Upper channel 354 Lower channel 356 Connecting Channel 370 Cooling fluid inlet / outlet 371 Supply Port Body 372 Exhaust port body 374 Cooling fluid supply port 376 Coolant Discharge Port 400 Side structural unit 405 Side structural unit 410 Main Plate 411 First Cell Storage Unit 412 Second Cell Housing 413 Interwing 415 Bottom Rib 416 Busbar guide protrusion 417 Cooling unit insertion groove 418 Guide stage 419 Second Line Storage Unit 419 First Line Storage Unit 450 end plate 456 Terminal hole 458 End guide stage 459 Connector mounting member accommodation section 500 Filler

Claims

1. A battery pack, a plurality of battery cells; a cooling unit disposed between the plurality of battery cells along a longitudinal direction of the battery pack; a side structural unit that houses the cooling unit and the plurality of battery cells; Including, the battery cell, the cooling unit, and the side structural unit are configured to be arranged at a predetermined distance ratio that is already set for mutual close contact, the side structural unit includes a first cell accommodating portion and a second cell accommodating portion that have a concave shape and are arranged alternately, When the battery cells are accommodated in the first cell accommodating portion and the second cell accommodating portion, a predetermined gap space is formed between the first cell accommodating portion and the second cell accommodating portion, The gap space is formed in a remaining area excluding an innermost area of ​​the concave shape of the first cell accommodating portion and the second cell accommodating portion.

2. A battery pack as described in claim 1, wherein the distance between the center of the battery cell provided in the first cell storage section and the center of the battery cell provided in the second cell storage section is configured to be determined according to the thickness of the side structural unit.

3. The cooling unit includes: a cooling tube disposed between the plurality of battery cells; a cooling flow path provided in the cooling tube for circulating a cooling fluid for cooling the battery cell; Including, 3. The battery pack according to claim 2, wherein a distance between the centers of adjacent battery cells in contact with one surface of the cooling tube is determined in conjunction with a distance between the centers of battery cells arranged opposite each other across the cooling tube.

4. The battery pack according to claim 3 , wherein a distance between the centers of the battery cells arranged opposite each other across the cooling tube is a distance that reflects a thickness of the cooling tube.

5. 4. The battery pack of claim 3, wherein a distance between a center of a battery cell provided in the first cell accommodating portion and a center of a battery cell provided in the second cell accommodating portion, a distance between the centers of adjacent battery cells in contact with one surface of the cooling tube, and a distance between the centers of battery cells arranged opposite each other across the cooling tube are determined in consideration of a diameter of the battery cell, a thickness of the cooling tube, and a contact angle between the battery cell and the cooling tube.

6. 6. The battery pack according to claim 5, wherein a contact angle between the battery cell and the cooling tube is 60°.

7. The minimum thickness of the first cell accommodating portion and the second cell accommodating portion is The battery pack according to claim 2 , wherein the distance between the first cell accommodating portion and the second cell accommodating portion is half the distance between the battery cells.

8. The battery cell The battery pack according to claim 1 , wherein only an innermost region of the concave shape is in contact with the inner surfaces of the first cell accommodating portion and the second cell accommodating portion.

9. The battery pack according to claim 1 , wherein the gap space is filled with a filling member.

10. A motor vehicle, A battery pack according to any one of claims 1 to 9, A vehicle, wherein a longitudinal direction of at least one of the battery packs is arranged perpendicular to a longitudinal direction of the vehicle so that the side structural unit can protect a plurality of the battery cells in the event of a frontal or rearal collision of the vehicle.

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