KR20240010424A - Battery pack and vehicle comprising the battery pack - Google Patents

Abstract

A battery pack according to an embodiment of the present invention has a plurality of battery cells, a filling member filled in the space between the plurality of battery cells, and is electrically connected to the plurality of battery cells, and has a filling member injection hole for injecting the filling member. Characterized in that it includes a busbar assembly.

Description

Battery pack, automobile comprising such battery pack {BATTERY PACK AND VEHICLE COMPRISING THE BATTERY PACK}

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

Secondary batteries, which are easy to apply depending on the product group and have electrical characteristics such as high energy density, are used not only in portable devices but also in electric vehicles (EV, Electric Vehicle) or hybrid vehicles (HEV, Hybrid Electric Vehicle) that are driven by an electrical drive source. It is universally applied. These secondary batteries are attracting attention as a new energy source for improving eco-friendliness and energy efficiency, not only because they have the primary advantage of being able to dramatically reduce the use of fossil fuels, but also because they do not generate any by-products due to energy use.

Types of secondary batteries currently widely used include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydrogen batteries, and nickel zinc batteries. The operating voltage of these unit secondary battery cells, that is, unit battery cells, is approximately 2.5V to 4.5V. Therefore, when a higher output voltage is required, a battery pack is formed by connecting a plurality of battery cells in series. Additionally, a battery pack may be constructed by connecting multiple battery cells in parallel depending on the charge/discharge capacity required for the battery pack. Accordingly, the number of battery cells included in the battery pack can be set in various ways depending on the required output voltage or charge/discharge capacity.

Meanwhile, when configuring a battery pack by connecting a plurality of battery cells in series/parallel, a battery module containing at least one battery cell is first configured, and other components are added using this at least one battery module. This is a common method of constructing a battery pack or battery rack.

Recently, there is an increasing demand for battery packs with a simpler structure that can increase energy density and increase manufacturing efficiency by reducing manufacturing costs and manufacturing times.

Accordingly, there is a need to find a way to provide a battery pack and a vehicle including the same that can increase energy density with a simpler structure and increase manufacturing efficiency by reducing manufacturing cost and manufacturing time.

Accordingly, the purpose of the present invention is to provide a battery pack that can increase energy density with a simpler structure and a vehicle including the same.

Additionally, another object of the present invention is to provide a battery pack that can increase manufacturing efficiency by reducing manufacturing costs and manufacturing times, and a vehicle including the same.

In order to solve the above object, the present invention provides a battery pack, comprising: a plurality of battery cells; A filling member filled in the space between the plurality of battery cells; and a bus bar assembly electrically connected to the plurality of battery cells and having a filling member injection hole for injecting the filling member.

Additionally, preferably, the bus bar assembly may be electrically connected to the anode and cathode of the battery cells within the opening space of the filling member injection hole.

Additionally, preferably, the opening space of the filling member injection hole may be provided to expose both the positive and negative electrodes of the battery cells.

Also, preferably, the total area of the opening space may be larger than the flow area of the filling member flowing between the battery cells when the filling member is injected.

Also, preferably, the filling member has a predetermined viscosity and may include at least two substances.

Also, preferably, the filling member may be prepared by mixing a predetermined resin and beads at a preset ratio.

Also, preferably, the predetermined resin may be provided as a silicone resin.

Also, preferably, the predetermined bead may be provided as a glass bubble.

Also, preferably, the bus bar assembly includes: a pair of bus bar covers disposed on one side of the plurality of battery cells and in which the filling member injection hole is formed; and a sub-bus bar provided between the pair of bus bar covers and connected to the anode and cathode of the battery cells.

Additionally, preferably, the pair of bus bar covers may be made of polyimide film.

Also, preferably, the sub bus bar is provided as a single layer and can be inserted between the pair of bus bar covers.

Also, preferably, the sub bus bar includes a bus bar bridge inserted between the pair of bus bar covers; an anode connection portion extending from the bus bar bridge, exposed within the opening space of the filling member injection hole, and connected to anodes of the battery cells; and a cathode connection portion extending from the bus bar bridge, exposed within the opening space of the filling member injection hole, and connected to the cathode of the battery cells.

Also, preferably, the plurality of filling member injection holes are provided, and the plurality of filling member injection holes include: an anode bus bar hole exposing the anode connection portion and having an opening space larger than the size of the anode connection portion; and a cathode bus bar hole exposing the cathode connection part and having an opening space larger than the size of the cathode connection part.

Also, preferably, a plurality of filling member injection holes are provided, and each of the plurality of filling member injection holes can expose both the anode connection part and the cathode connection part within one opening space.

Additionally, preferably, each of the plurality of filling member injection holes may have an opening space larger than the combined size of the anode connection portion and the cathode connection portion.

Also, preferably, the anode bus bar hole and the cathode bus bar hole may be arranged to face each other with the bus bar bridge between them.

Additionally, the present invention provides a method for manufacturing a battery pack, including the steps of placing a cooling unit between a plurality of battery cells and aligning the battery cells and the cooling unit through a side structure unit to accommodate the battery cells and the cooling unit; A step of electrically connecting the battery cells within the opening space of the filling member injection hole of the bus bar assembly where the filling member injection hole is formed on the upper side of the plurality of battery cells; and injecting and applying a filling member from the top to the bottom of the battery cells along the vertical direction of the battery cells through the opening space of the filling member injection hole.

Also, preferably, the filling member may be prepared by mixing a predetermined resin and beads at a preset ratio.

Also, preferably, the mixing ratio of the predetermined resin and beads can be set to 100:60 (resin: glass bubble).

Additionally, the present invention provides an automobile, characterized in that it includes at least one battery pack according to the above-described embodiments.

According to the various embodiments described above, a battery pack capable of increasing energy density with a simpler structure and a vehicle including the same can be provided.

In addition, according to the various embodiments described above, a battery pack that can increase manufacturing efficiency by reducing manufacturing cost and manufacturing time, and a vehicle including the same can be provided.

The following drawings attached to this specification illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the detailed description of the invention described later, so the present invention includes the matters described in such drawings. It should not be interpreted as limited to only .
1 is a diagram for explaining a battery pack according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view of the battery pack of FIG. 1.
FIG. 3 is a diagram for explaining the battery cells of the battery pack of 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.
Figure 7 is a bottom view of the battery cell of Figure 3.
FIG. 8 is a diagram for explaining the bus bar assembly of the battery pack of FIG. 2.
FIG. 9 is a diagram for explaining the connecting bus bar unit of the bus bar assembly of FIG. 8.
Figure 10 is an exploded perspective view of the connection bus bar unit of Figure 9.
FIG. 11 is an enlarged view for explaining main parts of the connection bus bar unit of FIG. 9.
FIG. 12 is a diagram for explaining a filling member injection hole structure according to another embodiment of the connection bus bar unit of FIG. 11.
FIG. 13 is a diagram for explaining the cooling unit of the battery pack of FIG. 2.
Figure 14 is an exploded perspective view of the cooling unit of Figure 13.
Figure 15 is a cross-sectional view of the cooling unit of Figure 13.
FIG. 16 is a diagram for explaining the side structure unit of the battery pack of FIG. 2.
FIG. 17 is a diagram for explaining the main plate of the side structure unit of FIG. 16.
FIGS. 18 and 19 are diagrams for explaining the combined structure of battery cells and cooling units through the side structure unit of FIG. 16.
FIGS. 20 to 22 are diagrams for explaining the formation of a pack case structure through injection of a filling member of the battery pack of FIG. 2.
FIG. 23 is a graph of test results showing viscosity and manufacturing cost according to the mixing ratio of the filling member of the battery pack of FIG. 2.
Figure 24 is a diagram for explaining a car according to an embodiment of the present invention.

The present invention will become more apparent by detailed description of preferred embodiments of the present invention with reference to the accompanying drawings. The embodiments described herein are shown as examples to aid understanding of the invention, and it should be understood that the present invention can be implemented with various modifications different from the embodiments described herein. Additionally, in order to aid understanding of the invention, the attached drawings are not drawn to actual scale and the dimensions of some components may be exaggerated.

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

Referring to FIGS. 1 and 2 , the battery pack 1 may be used as an energy source in an electric vehicle or a hybrid vehicle. Hereinafter, the battery pack 1 provided for the electric vehicle, etc. will be described in more detail in the related drawings below.

The battery pack 1 may include a plurality of battery cells 100, a bus bar assembly 200, and a filling member 500.

The plurality of battery cells 100 may be provided as secondary batteries, such as a cylindrical secondary battery, a pouch-shaped secondary battery, or a prismatic secondary battery. Hereinafter, in this embodiment, the description will be limited to the fact that the plurality of battery cells 100 are cylindrical secondary batteries. Hereinafter, each battery cell 100 will be examined in more detail with reference to the related drawings below.

The filling member 500 may be filled in the space between the plurality of battery cells 100. Here, the filling member 500 is a potting resin and may be prepared by mixing with beads such as glass bubbles. The filling member 500 will be discussed in more detail in the related description below.

The bus bar assembly 200 may be electrically connected to the plurality of battery cells 100. The bus bar assembly 200 may be formed with filling member injection holes 242 and 244 for injecting the filling member 500.

In this embodiment, the filling member 500 is injected more directly and quickly into the space between the battery cells 100 through the filling member injection holes 242 and 244 provided in the bus bar assembly 200. Therefore, the process time can be further shortened during the injection process for injecting the filling member 500, thereby significantly increasing process efficiency.

Additionally, the bus bar assembly 200 may be electrically connected to the anode 40 and cathode 20a of the battery cells 100 within the opening space of the filling member injection holes 242 and 244.

In this embodiment, both the injection of the filling member 500 and the electrical connection of the battery cells 100 can be implemented through the filling member injection holes 242 and 244, resulting in a bus bar assembly with a simpler structure ( 200), the structure of the entire battery pack 10 can be simplified to further increase manufacturing efficiency.

Hereinafter, we will look at the battery pack 1 according to this embodiment in more detail.

FIG. 3 is a diagram for explaining the battery cell of the battery pack of FIG. 2, FIG. 4 is a partial cross-sectional view showing the internal structure of the battery cell of FIG. 3, and 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.

Referring to FIGS. 3 to 7 , the battery cell 100 includes an electrode assembly 10, a battery can 20, a cap plate 30, and a first electrode terminal 40. In addition to the above-described components, the battery cell 100 additionally includes an insulating gasket 50 and/or an upper current collector plate 60 and/or an insulating plate 70 and/or a lower current collector plate 80 and/or A sealing gasket 90 may be further included.

The electrode assembly 10 includes a first electrode plate with a first polarity, a second electrode plate with a second polarity, and a separator interposed between the first electrode plate and the second electrode plate. The first electrode plate is a positive electrode plate or a negative electrode plate, and the second electrode plate corresponds to an electrode plate having a polarity opposite to that of the first electrode plate.

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

The first electrode plate includes a first electrode current collector and a first electrode active material applied on one or both sides of the first electrode current collector. An uncoated area in which the first electrode active material is not applied exists at one end of the first electrode current collector in the width direction (direction parallel to the Z axis). The uncoated portion functions as a first electrode tab. The first electrode tab 11 is provided on the top of the electrode assembly 10 accommodated in the battery can 20 in the height direction (direction parallel to the Z axis).

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

The battery can 20 is a cylindrical container with an opening formed at the bottom, and is made of a conductive metal material. The side and top surfaces of the battery can 20 are formed as one piece. The top surface of the battery can 20 has a substantially flat shape. The battery can 20 accommodates the electrode assembly 10 through an opening formed at the bottom, and also accommodates the electrolyte.

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

The battery can 20 may include a beading portion 21 and a crimping portion 22 formed at its bottom. The beading portion 21 is formed at the lower part of the electrode assembly 10. The beading portion 21 is formed by press fitting around the outer peripheral 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 coming out through the opening formed at the bottom of the battery can 20, and the cap plate 30 It can function as a seated support.

The crimping part 22 is formed at the lower part of the beading part 21. The crimping portion 22 has an extended and bent shape to surround the outer peripheral surface of the cap plate 30 disposed below the beading portion 21 and a portion of the lower surface of the cap plate 30.

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

The cap plate 30 may further include a venting portion 31 formed to prevent an increase in internal pressure due to gas generated inside the battery can 20. The venting portion 31 corresponds to an area of the cap plate 30 that has a thinner thickness compared to the surrounding area. The venting portion 31 is structurally weak compared to the surrounding area. Therefore, when an abnormality occurs in the battery cell 100 and the internal pressure increases above a certain level, the venting portion 31 is ruptured and the gas generated inside the battery can 20 is discharged.

A hole may be formed in advance on the upper surface of the battery can 20 before placing the first electrode terminal 40 and the insulating gasket 50. It is not limited to this, and the hole may be formed in other ways. For example, a hole is formed as the first electrode terminal 40 is inserted, a hole with a different diameter is formed in advance, or the upper surface is notched or notched in advance to facilitate insertion of the first electrode terminal 40. It can be done. In other words, you can expand the hole to the desired size, or you can drill a notch to create a small hole and then expand it to the desired size. In addition, it is of course possible that other methods of forming the hole may be used.

The battery cell 100 according to an embodiment of the present invention has a structure in which both a positive terminal and a negative terminal are present at the top, and because of this, the upper structure is more complicated than the lower structure. Accordingly, a venting portion 31 may be formed on the cap plate 30 forming the lower surface of the battery cell 100 to smoothly discharge the gas generated inside the battery can 20.

The venting portion 31 may be formed continuously in a circle on the cap plate 30. It is not limited to this, and the venting portion 31 may be formed discontinuously in a circle on the cap plate 30, or may be formed in a straight line or any other shape.

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

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

The top surface of the battery can 20 and the first electrode terminal 40 have opposite polarities and face the same direction. Additionally, a step may be formed between the first electrode terminal 40 and the upper surface of the battery can 20. Specifically, when the entire upper surface of the battery can 20 has a flat shape or a shape that protrudes upward from its center, the exposed terminal portion 41 of the first electrode terminal 40 is exposed to the battery can 20. It may protrude further upward than the upper surface of . On the contrary, when the upper surface of the battery can 20 has a concave shape downward from the center, that is, in the direction toward the electrode assembly 10, the upper surface of the battery can 20 is connected to the first electrode terminal. It may protrude further upward than the exposed terminal portion 41 of (40).

The insulating gasket 50 is interposed between the battery can 20 and the first electrode terminal 40 to prevent the battery can 20 and the first electrode terminal 40, 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.

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 insertion portion 52 is interposed between the insertion terminal portion 42 of the first electrode terminal 40 and the battery can 20. The insulating gasket 50 may be made of, for example, an insulating resin material.

When the insulating gasket 50 is made of a resin material, the insulating gasket 50 may be coupled to the battery can 20 and the first electrode terminal 40 by, for example, heat fusion. In this case, 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.

A second electrode terminal in which the entire upper surface of the battery can 20, excluding the area occupied by the first electrode terminal 40 and the insulating gasket 50, has an opposite polarity to the first electrode terminal 40. Corresponds to (20a).

The battery cell 100 according to an embodiment of the present invention has a first electrode terminal 40 having a first polarity on one side of the longitudinal direction (direction parallel to the Z axis) and an electrical connection between the first electrode terminal 40 and the first electrode terminal 40. and is provided with a second electrode terminal 20a having a second polarity. That is, in the battery cell 100 according to an embodiment of the present invention, a pair of electrode terminals 40 and 20a are located in the same direction, so when a plurality of battery cells 100 are electrically connected, It is possible to place electrical connection components such as the bus bar assembly 200 below only on one side of the battery cells 100. This can result in simplification of the structure of the battery pack 1 and improvement in energy density.

Below, we will look at the bus bar assembly 200 for electrical connection with the plurality of battery cells 100 in more detail.

Referring again to FIG. 2, the bus bar assembly 200 is provided on one side of the battery cells 100, specifically, on the upper side (+Z-axis direction) of the battery cells 100, and is connected to the plurality of batteries. It may be electrically connected to the cells 100. Electrical connection of the bus bar assembly 200 may be parallel and/or series connection.

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

Hereinafter, the configurations of the bus bar assembly 200 will be looked at in more detail.

FIG. 8 is a diagram for explaining the bus bar assembly of the battery pack of FIG. 2, FIG. 9 is a diagram for explaining the connection bus bar unit of the bus bar assembly of FIG. 8, and FIG. 10 is a view for explaining the connection bus bar unit of FIG. 9. is an exploded perspective view, and FIG. 11 is an enlarged view for explaining the main part of the connection bus bar unit of FIG. 9, and FIG. 12 is an exploded view for explaining the filling member injection hole structure according to another embodiment of the connection bus bar unit of FIG. 11. It is a drawing.

Referring to FIGS. 8 to 11 and the preceding FIG. 2, the bus bar assembly 200 includes a main bus bar unit 210, a connecting bus bar unit 230, an interconnection board 260, and a connector terminal 290. may include.

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

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

The connection bus bar unit 230 may be provided as a single unit sized to cover all of the plurality of battery cells 100 or may be provided as a plurality to cover the plurality of battery cells 100. Hereinafter, in this embodiment, the description will be limited to the fact that the connection bus bar unit 230 is provided in plural numbers.

The plurality of connected bus bar units 230 may each include a bus bar cover 240 and a sub bus bar 250.

The bus bar cover 240 covers the upper side of the plurality of battery cells 100 and may be provided in a substantially flat plate shape. The shape and size of the bus bar cover 240 may vary depending on the number or capacity of battery cells 100 required for the battery pack 1.

The bus bar cover 240 may be made of an insulating material. For example, the bus bar cover 240 may be made of polyimide film. It is not limited to this, and of course, the bus bar cover 240 may also be provided with other insulating members made of insulating materials.

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

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

The anode bus bar hole 242 and the cathode bus bar hole 244 may be the previous filling member injection holes 242 and 244. That is, the filling member injection holes 242 and 244 may serve to guide the connection between the anode 40 and the cathode 20a of the battery cells 100. That is, the filling member injection holes 242 and 244 may be formed in a pair of bus bar covers 240.

Specifically, the filling member injection holes 242 and 244 may be provided in plural numbers.

The plurality of filling member injection holes 242 and 244 expose an anode connection portion 254 to be described later, and an anode bus bar hole 242 having an opening space larger than the size of the anode connection portion 254 and a cathode to be described later. It exposes the connection portion 256 and may include a cathode bus bar hole 244 having an opening space larger than the size of the cathode connection portion 256. Here, the anode bus bar hole 242 and the cathode bus bar hole 244 may be arranged to face each other with a bus bar bridge 252, which will be described later, interposed therebetween.

Hereinafter, the anode bus bar hole 242 and the cathode bus bar hole 244 constituting the filling member injection holes 242 and 244 will be looked at in more detail.

The anode bus bar holes 242 have an opening space of a predetermined size and may be provided in plural numbers. An anode connection portion 254, which will be described later, may be exposed through the anode bus bar hole 242. Here, the anode bus bar hole 242 may be formed to have an opening space larger than the size of the anode connection portion 254, which will be described later, in order to improve process workability and improve the injection efficiency of the filling member 500, which will be described later.

The anode bus bar hole 242 can more efficiently guide the electrical connection between the anode connector 254, which will be described later, and the first electrode terminal 40 (see FIG. 3), which is the anode of the battery cells 100.

In addition, when the filling member 500, which will be described later, is injected through the opening space of the anode bus bar hole 242, the injection efficiency of the filling member 500 can be significantly increased. Specifically, the filling member 500 provided with potting resin 500, which will be described later, is formed through the opening space of the anode bus bar hole 242 in the vertical direction (Z-axis direction) from the top to the bottom of the battery pack 1. ) can be injected more directly, so injection efficiency between the battery cells 100 can be significantly improved.

The cathode bus bar hole 244 is disposed to face the anode bus bar hole 242, has an opening space of a predetermined size like the anode bus bar hole 242, and may be provided in plural pieces. Here, the cathode bus bar hole 244 may be formed to have an opening space larger than the size of the cathode connection portion 256, which will be described later, in order to improve process workability and improve the injection efficiency of the filling member 500, which will be described later.

The cathode bus bar hole 244 is an electrical connection between the cathode connector 256, which will be described later, and the battery can 20 (see FIG. 3), which is the cathode of the battery cells 100, and specifically, the second electrode terminal 20a. can be guided more efficiently.

In addition, when the filling member 500, which will be described later, is injected through the opening space of the cathode bus bar hole 244, the injection efficiency of the filling member 500 can be significantly increased. Specifically, the filling member 500 provided with potting resin 500, which will be described later, is formed through the opening space of the cathode bus bar hole 244 in the vertical direction (Z-axis direction) from the top to the bottom of the battery pack 1. ) can be injected more directly, so injection efficiency between the battery cells 100 can be significantly improved.

Meanwhile, the total area of the opening space of the anode bus bar hole 242 and the opening space of the cathode bus bar hole 244, that is, the opening space of the filling member injection holes 242 and 244, is the size of the filling member. When the 500 is injected, the flow area may be larger than the flow area of the filling member 500 flowing between the battery cells 100. This is to prevent a delay in the overall injection process time by preventing a delay in the injection of the filling member 500.

Meanwhile, referring to FIG. 12, the opening space of the filling member injection hole 243 is configured to expose both the anode (40, see FIG. 3) and the cathode (20, see FIG. 3) of the battery cells 100. It may also be possible to prepare. Specifically, the plurality of filling member injection holes 243 can each expose both the anode connection part 254 and the cathode connection part 256, which will be described later, within one opening space. Accordingly, within each opening space of the filling member injection hole 243, both the anode (40, see FIG. 3) and the cathode (20, see FIG. 3) of the battery cells 100 are connected to an anode connection portion 254, which will be described later. And it can be connected to the cathode connection part 256.

According to this embodiment of the present invention, the anode (40, see FIG. 3) and the cathode (20, see FIG. 3) of the battery cells 100 within one opening space of the filling member injection hole 243 are described later. Since electrical connection with the anode connection part 254 and the cathode connection part 256 can be implemented, the process of forming the filling member injection hole 243 of the pair of bus bar covers 240 can be further simplified.

In addition, each of the plurality of filling member injection holes 243 may have an opening space larger than the combined size of the anode connection part 254 and the cathode connection part 256, which will be described later. Therefore, when making the electrical connection, the convenience of the electrical connection process within the opening space can be further secured. Additionally, the injection efficiency of the filling member 500 through the filling member injection hole 243 can also be improved.

Referring again to FIGS. 8 to 11 and the preceding FIG. 2, the guide hole 246 can guide the assembly position of the bus bar assembly 200. Specifically, the guide hole 246 can guide the proper position arrangement of the connection bus bar unit 230 by fixing the connection bus bar unit 230 to the side structure unit 400.

The guide holes 246 may be provided in plural numbers. Bus bar guide protrusions 416 of the side structure unit 400, which will be described later, may be inserted into the plurality of guide holes 246.

The sub-bus bar 250 is for electrical connection with the first electrode terminal 40, which is the positive electrode, and the second electrode terminal 20a, which is the negative electrode, of the plurality of battery cells 100, and the bus bar cover 240 ) It may be provided on the upper side or inserted into a pair of bus bar covers 240. Hereinafter, in this embodiment, the description will be limited to being inserted into or coupled to the bus bar cover 240.

The sub bus bar 250 may include a bus bar bridge 252, an anode connection part 254, and a cathode connection part 256.

The bus bar bridge 252 is inserted into the pair of bus bar covers 240 and may be formed to have a predetermined length along the width direction (X-axis direction) of the battery pack 1. The bus bar bridge 252 is connected to the arrangement structure of the battery cells 100 in the width direction (X-axis direction) of the battery pack 1 to increase the efficiency of electrical connection with the battery cells 100. It may be provided in a corresponding shape. Accordingly, in this embodiment, the bus bar bridge 252 may be arranged in a zigzag shape in the width direction (X-axis direction) of the battery pack 1.

The bus bar bridge 252 may be provided in plural numbers. 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.

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

The anode connection portion 254 extends integrally from the bus bar bridge 252 and protrudes, and may be disposed within the anode bus bar hole 242. Specifically, the anode connection portion 254 may be exposed within the opening space of the anode bus bar hole 242, that is, the filling member injection hole 242.

The anode connection portion 254 may be electrically connected to the first electrode terminal 40 (see FIG. 3), which is the anode of the battery cell 100. The electrical connection may be performed through a welding process for electrical connection, such as laser welding or ultrasonic welding.

Since the connection between the positive electrode connector 254 and the positive electrode 40 (first electrode terminal) of the battery cell 100 is performed in the opening space of the positive bus bar hole 242, during the connection, A welding process, etc. can be performed directly in the opening space without any additional processes.

The cathode connection part 256 extends integrally from the bus bar bridge 252, protrudes in a direction opposite to the anode connection part 254, and may be disposed in the cathode bus bar hole 244. Specifically, the cathode connection portion 256 may be exposed within the opening space of the cathode bus bar hole 244, that is, the filling member injection hole 244.

The cathode connection portion 256 may be electrically connected to the second electrode terminal 20a (see FIG. 3), which is the cathode of the battery cell 100. The electrical connection may be performed through a welding process for electrical connection, such as laser welding or ultrasonic welding.

Since the connection between the cathode connector 256 and the cathode (20a, second electrode terminal) of the battery cell 100 is performed in the opening space of the cathode bus bar hole 244, during the connection, A welding process, etc. can be performed directly in the opening space without any additional processes.

The interconnection board 260 is connected to the external sensing line and may be provided at one end (-Y axis direction) of the battery pack 1. The location of the interconnection board 260 may change depending on design, etc., and may be provided in other locations that enable connection with the external sensing line. In addition, the interconnection board 260 may be provided in plural numbers depending on the number or capacity of the battery cells 100 of the battery pack 1.

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 and 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.

The interconnection board 260 may be provided with a thermistor to check the temperature status of the battery cells 100. The thermistor may be built into the interconnection board 260 or may be separately mounted outside the interconnection board 260. The connector terminals 290 may be provided as a pair. This pair of connector terminals 290 is for connection to an external charge/discharge line and may be provided as a high voltage connector terminal.

Referring again to FIG. 2, the battery pack 1 may include a cooling unit 300.

The cooling unit 300 is for cooling the battery cells 100 and is disposed on the lower side (-Z axis direction) of the bus bar assembly 200, and in the longitudinal direction (Y) of the battery pack 1. It may be disposed between the plurality of battery cells 100 along the axial direction.

A plurality of such cooling units 300 may be provided.

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 placed in contact with the battery cells 100 facing each other to improve cooling performance.

Below, we will look at the cooling unit 300 in more detail.

FIG. 13 is a diagram for explaining the cooling unit of the battery pack of FIG. 2, FIG. 14 is an exploded perspective view of the cooling unit of FIG. 13, and FIG. 15 is a cross-sectional view of the cooling unit of FIG. 13.

Referring to FIGS. 13 to 15 and the preceding FIG. 2, the cooling unit 300 includes a cooling tube 310, a cooling passage 350, and a cooling fluid inlet and outlet 370. can do.

The cooling tube 310 is formed to have a predetermined length along the longitudinal direction (Y-axis direction) of the battery pack 1, is disposed between the plurality of battery cells 100, and circulates a cooling fluid described later therein. A cooling passage 350 may be provided for. In this embodiment, the cooling fluid may be water, and may include not only water but also one or more fluids capable of exchanging heat with the surrounding environment.

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

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

The cooling tube 310 may be placed in contact with the outer surface of the plurality of battery cells 100 to further increase the cooling performance of the battery cells 100. The cooling tube 310 may be adhesively fixed to the plurality of battery cells 100 through a filling member 500 or a separate adhesive member, which will be described later.

At one end (-Y-axis direction) of the cooling tube 310, a cooling fluid guide portion 318 may be provided to guide the cooling fluid into the cooling passage 350, which will be described later. The cooling fluid guide portion 318 is formed at one end (-Y-axis direction) of the cooling tube 310 in the longitudinal direction (Y-axis direction), and may be provided as a pair. One of the pair of cooling fluid guide parts 318 communicates with the upper flow path 352 of the cooling flow path 350, which will be described later, and the other of the pair of cooling fluid guide parts 318 will be described later. It may be in communication with the lower flow path 354 of the cooling flow path 350. Specifically, one of the pair of cooling fluid guide parts 318 is located at the upper (+Z-axis direction) side of the cooling tube 310 in the height direction (Z-axis direction) in communication with the upper flow path 352, which will be described later. is provided in, the other of the pair of cooling fluid guide parts 318 is located at the lower side (-Z axis direction) in the height direction (Z-axis direction) of the cooling tube 310 in communication with the lower flow passage 354, which will be described later. ) can be provided.

The cooling passage 350 circulates cooling fluid for cooling the battery cells 100, is provided within the cooling tube 310, and may be connected in communication with a cooling fluid inflow and outflow portion 370 to be described later.

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

The upper passage 352 is disposed on the upper side of the cooling tube 310 so as to be provided close to the bus bar assembly 200, and has a predetermined length along the longitudinal direction (Y-axis direction) of the cooling tube 310. It can be formed as The upper flow path 352 may be connected in communication with the cooling fluid supply port 374 of the cooling fluid inflow and outflow portion 370.

The upper passage 352 may be provided in at least one or more plurality. Hereinafter, in this embodiment, the description will be limited to the fact that a plurality of upper passages 352 are provided to ensure cooling performance.

The lower flow path 354 is disposed on the lower side (-Z-axis direction) of the cooling tube 310 to be spaced apart from the at least one upper flow path 352, and extends in the longitudinal direction (Y-axis) of the cooling tube 310. direction) and can be formed to a predetermined length. The lower flow path 354 may be connected in communication with the cooling fluid discharge port 376 of the cooling fluid inflow and outflow portion 370.

The lower flow path 354 may be provided in at least one or more plurality. Hereinafter, in this embodiment, the description will be limited to the fact that a plurality of lower flow passages 354 are provided to ensure cooling performance.

The connection flow path 356 includes the at least one upper flow path, in this embodiment, a plurality of upper flow paths 352 and the at least one lower flow path, in this embodiment, a plurality of lower flow paths 354. You can connect.

The connection passage 356 may be provided at the other end (+Y-axis direction) of the cooling tube 310 opposite the cooling fluid inflow and outflow portion 370 to maximize the cooling passage 350. there is.

In the case of this embodiment, when the cooling fluid circulates in the cooling passage 350, the cooling fluid supplied from the cooling fluid supply port 374 is preferentially directed to the upper passage 352 disposed near the bus bar assembly 200. After being supplied, it may flow toward the cooling fluid discharge port 376 through the connection passage 356 and the lower passage 354.

Accordingly, in this embodiment, cold cooling fluid is preferentially supplied to the area near the busbar assembly 200, which has a relatively higher temperature distribution within the battery pack 1, so that the battery cells 100 Cooling performance can be significantly improved.

The cooling fluid inflow and outflow portion 370 may be connected to the cooling tube 310 in communication with the cooling passage 350 of the cooling tube 310. The cooling fluid inflow and outflow portion 370 may be exposed to the outside of the side structure unit 400, which will be described later, and may be connected in communication with an external cooling line.

The cooling fluid inflow and outflow portion 370 may be provided on one side (-Y-axis direction) of the battery pack 1 along the longitudinal direction (Y-axis direction). The cooling tube 310 connected to the cooling fluid inflow and outflow portion 370 is connected to the battery pack 1 in the longitudinal direction (Y-axis direction) of the battery pack 1 from the cooling fluid inflow and outflow portion 370. It can be formed to a predetermined length toward the other side (+Y axis direction).

The cooling fluid inlet/outlet 370 may include inlet/outlet bodies 371 and 372, a cooling fluid supply port 374, and a cooling fluid discharge port 376.

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

The supply port body 371 covers one end (-Y-axis direction) of the cooling tube 310, and may be combined with the discharge port body 372, which will be described later. A supply port through hole 371a through which a cooling fluid supply port 374, which will be described later, passes through may be formed in the supply port body 371. The cooling fluid supply port 374, which will be described later, may pass through the supply port through hole 371a and communicate with the upper flow path 352, which will be described later, through the cooling fluid guide portion 318. Specifically, the cooling fluid supply port 374, described later, is provided through the cooling fluid guide portion 318 located on the upper side (+Z-axis direction) of the cooling fluid guide portion 318 of the cooling tube 310. It may be connected to the upper flow path 352.

The discharge port body 372 is coupled to the supply port body 371 on the opposite side of the supply port body 371 with one end (-Y axis direction) of the cooling tube 310 in between to cool the supply port body 371. It can cover one end (-Y axis direction) of the tube 310. Here, the discharge port body 372 and the supply port body 371 may be assembled together through press hemming.

A discharge port through-hole 372a through which a cooling fluid discharge port 376, which will be described later, passes through may be formed in the discharge port body 372. The cooling fluid discharge port 376, which will be described later, may pass through the discharge port through hole 372a and communicate with the lower flow path 354, which will be described later, through the cooling fluid guide portion 318. Specifically, the cooling fluid discharge port 376, which will be described later, flows through the cooling fluid guide portion 318 located on the lower side (-Z axis direction) of the cooling fluid guide portions 318 of the cooling tube 310. It can be connected to Euro (354).

The cooling fluid supply port 374 is provided in the supply port body 371 of the inlet and outlet bodies 371 and 372, and may be connected in communication with the upper flow path 352. Here, the cooling fluid supply port 374 may be coupled to the supply port body 371 by caulking. The cooling fluid supply port 374 may be connected in communication with the external cooling line.

The cooling fluid discharge port 376 is provided on the discharge port body 372 of the inlet and inlet bodies 371 and 372, and may be connected in communication with the lower flow path 374. Here, the cooling fluid discharge port 376 may be caulked to the discharge port body 372. The cooling fluid discharge port 376 is spaced apart from the cooling fluid supply port 374 by a predetermined distance and may be connected in communication with the external cooling line.

Referring again to FIG. 2, the battery pack 1 may include a side structure unit 400.

The side structure unit 400 is made of plastic resin, supports the battery cells 100, secures the rigidity of the battery cells 100, and forms the side appearance of the battery pack 1. can do.

Hereinafter, the side structure unit 400 will be examined in more detail through the related drawings below.

FIG. 16 is a diagram for explaining the side structure unit of the battery pack of FIG. 2, and FIG. 17 is a diagram for explaining the main plate of the side structure unit of FIG. 16.

16 and 17, the side structure unit 400 supports the battery cells 100, secures the rigidity of the battery cells 100, and supports the battery pack 1 (see FIG. 2). It can function as a pack case that forms the outer side of the battery pack (1, see FIG. 2) and forms the exterior of the battery pack (see FIG. 2).

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

The side structure unit 400 may include a main plate 410 and an end plate 450.

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

The plurality of main plates 410 ensure the rigidity of the battery cells 100 and the cooling unit 300 and also occupy a predetermined space within the battery pack 1 (see FIG. 2), which will be described later. The injection amount of the filling member 500 can be reduced. In the case of the filling member 500 made of silicone resin, which will be described later, it has a relatively high cost, and the battery pack 1 is manufactured by reducing the amount of silicone resin injected through the plurality of main plates 410. City cost competitiveness can be further secured.

The plurality of main plates 410 each include a first cell accommodating part 411, a second cell accommodating part 412, an inter wing 413, a bottom rib 415, a bus bar guide protrusion 416, It may include a cooling unit insertion groove 417 and a guide jaw 418.

The first cell receiving portion 411 may be provided in front of the main plate 410 (+X-axis direction) along the longitudinal direction (Y-axis direction) of the main plate 410. The first cell accommodating portion 411 may accommodate the plurality of battery cells 100 disposed in the longitudinal direction (Y-axis direction) of the battery pack 1. To this end, a plurality of first cell receiving portions 411 may be provided in front of the main plate 410 (+X-axis direction).

The plurality of first cell accommodating portions 411 are each provided 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.

The second cell receiving portion 412 may be provided at the rear (-X-axis direction) of the main plate 410 along the longitudinal direction (Y-axis direction) of the main plate 410. The second cell accommodating portion 412 can accommodate the plurality of battery cells 100 disposed in the longitudinal direction (Y-axis direction) of the battery pack 1. To this end, a plurality of second cell receiving portions 412 may be provided at the rear (-X-axis direction) of the main plate 410.

The plurality of second cell accommodating portions 412 are each provided 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.

The plurality of second cell receiving portions 412 are configured to accommodate the plurality of second cell receiving portions 412 in the front-back direction (X-axis direction) of the main plate 410 to accommodate as much as possible the battery cells 100 provided with the cylindrical secondary battery. It may be arranged to be staggered with the first receiving portion 411.

The inter wings 413 are provided in plural pieces and extend along the width direction (X-axis direction) of the main plate 410 to partition between the plurality of first and second receiving portions 411 and 412. A protrusion may be formed. Specifically, the plurality of inter wings 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 inter wings 413, the inter wings 413 protruding forward (+ axis direction) of the main plate 410 partition the plurality of first cell receiving portions 411. , Among the plurality of inter wings 413, the inter wings 413 protruding rearward (-axial direction) of the main plate 410 may partition the plurality of second cell receiving portions 412.

The bottom rib 415 is provided at the bottom of the main plate 410 and can support the bottom of the battery cells 100 when the main plate 410 accommodates the battery cells 100.

The bottom rib 415 may be formed to protrude further downward (in the -Z-axis direction) than the bottom of the battery cells 100 when the main plate 410 of the battery cells 100 is accommodated.

The bus bar guide protrusion 416 is for fixing the connecting bus bar unit 230 when assembling the bus bar assembly 200, and is provided on the upper surface of the main plate 410, and is provided at least one or It may be provided in more than one number. Hereinafter, in this embodiment, the description will be limited to the fact that the bus bar fixing holes 416 are provided in plural numbers.

The plurality of bus bar guide protrusions 416 are inserted into the guide hole 246 of the bus bar cover 240 when assembling the bus bar assembly 200, and form the connection bus bar unit 230. It can guide positioning. Since the connection bus bar unit 230 is inserted into or coupled to and fixed to the plurality of bus bar guide protrusions 416, a welding process for electrical connection of the bus bar assembly 200 can be performed more stably. And, the welding quality during the welding process can be further improved.

The cooling unit insertion groove 417 is for accommodating 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). When the main plates 410 are coupled, the end of the cooling unit 300 is placed in the cooling unit insertion groove 417 and can be fixed more stably.

The guide jaws 418 may be provided to protrude at a predetermined height from upper ends of both sides along the longitudinal direction (Y-axis direction) of the main plate 410. When assembly of the side structure unit 400 is completed by combining the main plates 410 and the end plate 450, which will be described later, the guide jaw 418 acts as an end guide for the end plate 450, which will be described later. Together with the chin 458, the edge of the side structure unit 400 can be formed.

The end plates 450 are provided as a pair and may be provided on both outermost sides of the side structure unit 400 along the width direction (X-axis direction). The pair of end plates 450, together with the main plate 410 disposed on the opposite side, can accommodate and support the battery cells 100.

The pair of end plates 450 may be provided with a terminal hole 456 and an end guide jaw 458.

The terminal hole 456 is for accommodating the connector terminal 290 and may be provided on one end of the end plate 450.

The end guide jaw 458 is formed along the upper edge of the end plate 450 and may be provided to protrude at the same height as the guide jaw 418. When assembly of the side structure unit 400 is completed, the end guide jaw 458 can form the edge of the side structure unit 400 together with the guide jaw 418 of the main plates 410. there is.

Below, we will look at the coupling structure of the battery cells 100 and the cooling units 300 through the side structure unit 400 in more detail.

FIGS. 18 and 19 are diagrams for explaining the combined structure of battery cells and cooling units through the side structure unit of FIG. 16.

Referring to FIGS. 18 and 19, first, among the battery cells 100, between the battery cells 100 arranged in two rows at the front and rear along the width direction (X-axis direction) of the battery pack (1, see FIG. 2). The cooling tube 310 of the cooling unit 300 may be fitted. The side structure unit 400 can accommodate battery cells 100 facing each other in the front-back direction (X-axis direction) of the battery cells 100 in which the cooling tube 310 is inserted.

Specifically, in the width direction (X-axis direction) of the battery pack (1, see FIG. 2), the end plate 450, battery cells 100, cooling tube 310, and battery cells 100 are disposed on the outermost side. ), the main plate 410 is disposed, and again, the battery cells 100, the cooling tube 310, the battery cells 100, and the main plate 410 may be disposed and combined in that order. Thereafter, in the width direction (X-axis direction) of the battery pack (1, see FIG. 2), the end plate 450 disposed on the outermost side of the opposite side is finally disposed and coupled to couple the side structure unit 400. The battery cells 100 and the cooling units 300 can be accommodated in the side structure unit 400 while completing the process.

Here, both ends of the cooling unit 300 are inserted into the cooling unit insertion groove 417 when the main plates 410 are coupled and the main plate 410 and the end plate 450 are coupled. The cooling unit 300 can be fixed more stably while preventing interference with the cooling unit 300.

Meanwhile, the cooling fluid inflow and outflow portions 370 provided at one end of the cooling units 300 may be arranged to protrude out of the side structure unit 400 for connection to an external cooling line, etc.

The side structure unit 400 according to the present embodiment connects the main plates 410 and the end plates 450 to the battery cells 100 and the cooling units 300. It is possible to form a side outer structure of the battery pack (1, see FIG. 2) while accommodating the. That is, the side structure unit 400 may function as a pack case that forms the exterior of the battery pack 1.

Accordingly, the battery pack (1, see FIG. 1) according to this embodiment can omit a separate additional pack case or pack housing structure through the side structure unit 400, thereby lowering the manufacturing cost and also lowering the manufacturing cost. Energy density can be further increased while reducing the overall size of the battery pack 1.

Referring again to FIG. 2, the filling member 500 is filled in the space between the cooling unit 300 and the plurality of battery cells 100 in the height direction (Z-axis direction) of the battery pack 1. You can. Meanwhile, in FIG. 2 , the filling member 500 is indicated with a hexahedral dotted line for convenience of understanding, and the filling member 500 includes the cooling unit 300 and the plurality of battery cells 100. The space in between can all be filled.

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

In addition, the filling member 500 fixes the plurality of battery cells 100 more stably and increases the heat dissipation efficiency of the plurality of battery cells 100, thereby improving the cooling performance of the battery cells 100. can be raised even further.

In addition, the filling member 500 prevents moisture or foreign substances from penetrating into the battery cells 100, prevents chain ignition when a thermal event occurs due to an abnormality in the battery cells 100, and prevents the The structural rigidity of the battery pack 10 can be increased.

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

Specifically, the filling member 500 may be made of silicone resin. It is not limited to this, and of course, the filling member 500 may be made of other resin materials that can improve the fixation and heat dissipation efficiency of the battery cells 100 in addition to the silicone resin.

The filling member 500 has a predetermined viscosity and may include at least two materials. Specifically, the filling member 500 may be prepared by mixing a predetermined resin and beads at a preset ratio. The filling member 500 can reduce the cost of the potting resin through mixing the beads, and adjust physical properties such as viscosity of the filling member 500 according to the mixing ratio.

The filling member 500 is a bead and may include a glass bubble. The glass bubble can lower the specific gravity of the filling member 500 and increase energy density relative to weight. Meanwhile, the filling member 500 may have a viscosity of approximately 250 cP when the base material and the curing agent are mixed, and when the glass bubble is mixed at 100:60 (resin: glass bubble), it may have a viscosity of approximately 1590 cP. You can have it. Mixing with the glass bubbles of the filling member 500 will be discussed in more detail in the related description below.

The filling member 500 covers the portion of the battery cells 100 that is not in contact with the cooling tube 310, thereby guiding the thermal balance of the battery cells 100, Local deterioration of the battery cells 100 can be prevented by preventing cooling deviation. Additionally, the safety of the battery cells 100 can be significantly improved by preventing local deterioration of the battery cells 100.

In addition, the filling member 500 is an insulator that prevents electricity from flowing to adjacent battery cells 100 when damage, etc. occurs due to an abnormal situation in at least one specific battery cell 100 among the plurality of battery cells 100. can perform its role.

The filling member 500 may be filled not only with the battery cells 100 but also with the bus bar assembly 200 . Specifically, the filling member 500 may be filled in the bus bar assembly 200 to cover the upper side of the bus bar assembly 200.

Here, the filling member 500 is connected to the bus without a disconnection space or separation space between the bus bar assembly 200 and the battery cells 100 in the vertical direction (Z-axis direction) of the battery cells 100. The space between the bar assembly 200 and the battery cells 100 may be continuously filled.

In this way, the filling member 500 according to the present embodiment continuously fills the battery cells 100 and the bus bar assembly 200 without interruption, so that the battery cells 100 and the bus bar assembly ( 200), the cooling performance of the battery pack 1 can be significantly improved by implementing even heat dispersion without heat dispersion deviation occurring in the area between the heat dissipation and heat dispersion areas.

In addition, the filling member 500 may be filled in parts other than the outer side of the side structure unit 400. Here, the filling member 500 can continuously fill the battery cells 100, the bus bar assembly 200, and the side structure unit 400 without interruption. Accordingly, the cooling performance of the battery pack 1 can be further improved.

Additionally, the filling member 500 may further include a material having high specific heat performance. Accordingly, the filling member 500 increases the thermal mass and delays the temperature increase of the battery cells 100 even in situations such as rapid charging and discharging of the battery cells 100. Can prevent rapid temperature rise.

Additionally, the filling member 500 may further include a material with high heat resistance. Accordingly, the filling member 500 can effectively prevent thermal runaway toward adjacent battery cells when a thermal event such as overheating occurs in at least one specific battery cell 100 among the plurality of battery cells 100. there is.

Additionally, the filling member 500 may further include a material with high flame retardant performance. Accordingly, the filling member 500 can minimize the risk of fire occurring when a thermal event such as overheating occurs in at least one specific battery cell 100 among the plurality of battery cells 100.

Below, we will look at the formation of the pack case structure through injection of the filling member 500 in more detail.

FIGS. 20 to 22 are diagrams for explaining the formation of a pack case structure through injection of a filling member of the battery pack of FIG. 2.

Referring to FIGS. 20 to 22, the manufacturer, etc. inject and apply the filling member 500 obtained by mixing the resin and glass bubbles through a resin injection device (I) to form the filling member made of the resin material. Through 500, the pack case structure of the upper and lower portions of the battery pack 1 (see FIG. 2) can be formed. Specifically, the filling member 500 covers the upper side of the bus bar assembly 200 from the upper side (+Z axis direction) of the battery pack 1, and the lower side (-Z axis direction) of the battery pack 1. It can be filled up to the protruding height h4 of the bottom rib 415 while covering the bottom of the battery cells 100 in the axial direction. Here, the protruding height h4 of the bottom rib 415 may be designed to a predetermined height considering the injection amount of the filling member 500.

During the injection and application process of the filling member 500 through the resin injection device (I), resin is applied to the bottom of the side structure unit 400 toward the lower side (-Z axis direction) when the filling member 500 is injected. An injection guider (S) may be provided to prevent leakage. The injection guider (S) may be made of a material such as Teflon for easy attachment and detachment after the filling member 500 is cured.

Meanwhile, during the injection and application process of the filling member 500, it is important to further reduce the manufacturing time while lowering the manufacturing cost to increase manufacturing efficiency, and to further increase the effect of the injected filling member 500. .

In order to reduce manufacturing costs and reduce manufacturing time, it is required that the filling member 500 be injected more quickly. The injection speed of the filling member 500 may be determined by the viscosity of the filling member 500, the structure of the side structure unit 400 that accommodates the battery cells 100, and the discharge flow rate of the resin injection device (I). You can.

Here, in relation to the viscosity of the filling member 500, low viscosity resin may be injected when the filling member 500 is injected. Since the filling speed of the resin slows down as viscosity increases, to increase manufacturing efficiency, a low-viscosity resin that can be filled above a certain speed can be applied.

For example, if the filling amount of the filling member 500 is 600ml and the target process time is 100sec, the filling member 500 must be filled with a flow rate condition of 6ml/sec. Considering this, it is important to inject low-viscosity resin when injecting the filling member 500, and in this embodiment, the filling member 500 may be prepared to have a viscosity of 2000 cP or less.

In addition, the filling member 500 may be mixed with the glass bubbles, as discussed above, in order to reduce the cost of the potting resin and control physical properties such as viscosity.

FIG. 23 is a graph of test results showing viscosity and manufacturing cost according to the mixing ratio of the filling member of the battery pack of FIG. 2.

Referring to FIG. 23, the filling member 500 can be mixed at a ratio that takes into account optimal viscosity and manufacturing cost. Figure 23 schematically shows the results in Table 1 below.

In FIG. 23 and Table 1 below, the test was conducted with the content ratio of glass bubbles, that is, beads, as resin : bead = 100 : In the test, the viscometer was of the LV type, spindle number 63 was used, and the RPM was set to 12RPM.

Looking at the test method, first, the specified masses of agent A and agent B are moved into each container. Afterwards, the bead mass of agent A and agent B is measured, added to each container, and mixed. Afterwards, agents A and B were transferred to a 100 ml container and mixed for 10 minutes at 1000 RPM using a stirrer, and the viscosity of the mixed resin was measured using a viscometer.

Case Bead content ratio (%)
100:X A(0.97g/CC) A-Bead (0.15g/CC) B(0.97g/CC) B-Bead (0.15g/CC) Viscosity (cP) Price (KRW/L) 1(1:0) 0 40.3ml(39.1g) 0ml 40.3ml(39.1g) 0ml 250 5626 2(1:0.1) 10 40ml(38.8g) 4ml(0.6g) 40ml(38.8g) 4ml(0.6g) 320 5235 3(1:0.2) 20 40ml(38.8g) 8ml(1.2g) 40ml(38.8g) 8ml(1.2g) 400 4908 4(1:0.3) 30 40ml(38.8g) 12ml(1.8g) 40ml(38.8g) 12ml(1.8g) 590 4632 5(1:0.4) 40 30ml(29.1g) 12ml(1.8g) 30ml(29.1g) 12ml(1.8g) 760 4396 6(1:0.5) 50 30ml(29.1g) 15ml(2.25g) 30ml(29.1g) 15ml(2.25g) 1190 4191 7(1:0.6) 60 30ml(29.1g) 18ml(2.7g) 30ml(29.1g) 18ml(2.7g) 1590 4011 8(1:0.7) 70 30ml(29.1g) 21ml(3.15g) 30ml(29.1g) 21ml(3.15g) 2190 3853 9(1:0.8) 80 30ml(29.1g) 24ml(3.6g) 30ml(29.1g) 24ml(3.6g) 2980 3712

As shown in Figure 23 and the results in Table 1 above, the test results show that as the bead content increases, the viscosity increases and the cost is reduced. As seen above, the viscosity of the filling member 500 is preferably 2000 cP or less, so in this embodiment, the mixing ratio of resin and beads (glass bubbles) is set to 100:60 (resin: glass bubbles). Ultimately, in this embodiment, the filling member 500 is mixed with a ratio of resin and glass bubbles of 100:60 and can have a viscosity of about 1590 cP. For example, in this embodiment, 24S When the required resin injection amount is 3.5L based on 4P and the resin flow area between the battery cells 100, cooling unit 300, and side structure unit 400 is about 20,000mm2, as seen above, the filling The total area of the opening spaces of the member injection holes 242 and 244 may be designed to be greater than or equal to the resin flow area. That is, the total area of the opening spaces of the filling member injection holes 242 and 244 may be formed to have an area larger than 20,000 mm2. Under the above conditions, the viscosity of the filling member 500 is 1590 cP, and the When the filling member 500, in which the mixing ratio of the resin and glass bubbles of the filling member 500 is 100:60, is injected at a resin injection flow rate of 0.37 LPM, the filling member 500 lasts about 9 minutes and 30 seconds without any delay during the injection. By continuous injection of 500, the filling member 500 can be injected up to 3.5L, which is the required resin injection amount.

As such, in this embodiment, the total area of the opening space of the filling member injection holes 242 and 244 is made larger than the resin flow area, and the low-viscosity mixed filling member 500 is injected, When injecting the filling member 500, there is no delay in the injection of the filling member 500, so the desired amount of filling member 500 can be effectively injected within the target process time.

Meanwhile, during the injection and application process of the filling member 500, the side structure unit 400 supports the battery cells 100 and the cooling unit 300 together with the injection guider (S) and supports the resin. It can act as a formwork to prevent leakage.

Accordingly, in this embodiment, during the injection and application process of the filling member 500 through the side structure unit 400, an additional injection guider jig structure in the lateral direction is not required, thereby reducing manufacturing costs. While reducing the cost, work efficiency can be significantly improved.

In addition, the side structure unit 400 guides the proper positioning of the connection bus bar unit 230 through the bus bar guide protrusion 416 inserted into the connection bus bar unit 230, so that the filling It is possible to effectively prevent distortion or misalignment of the connection bus bar unit 230 that may occur when the member 500 is injected.

In addition, when the filling member 500 is injected, the injection accuracy of the filling member 500 is improved through the guide jaw 418 and the end guide jaw 458 formed on the upper edge of the side structure unit 400. It is easy to inject the filling member 500 so as to cover the bus bar assembly 200 more reliably, and overflow of the filling member 500 can also be effectively prevented.

Here, the side structure unit 400 exposes components connected to external devices such as the interconnection board 260, connector terminal 290, and cooling fluid inflow and outflow portion 370 to the outside, and the filling member When injecting or applying (500), problems such as interference with these components may not occur.

Accordingly, in this embodiment, the pack case structure of the battery pack (1, see FIG. 1) is formed through the side structure unit 400 and the filling member 500, and a plurality of plates as in the prior art. The assembly process of the battery pack 1 can be simplified compared to forming the pack case structure as a complex assembly of the battery pack 1, and the manufacturing cost can be significantly lowered to ensure cost competitiveness.

In addition, in this embodiment, the pack case structure provided by the side structure unit 400 and the filling member 500 is compared to the pack case structure provided by the conventional cell frame structure composed of an assembly of a plurality of plates. Therefore, the size of the entire battery pack 1 can be reduced, and the energy density can also be significantly increased.

A method of manufacturing the battery pack 1 having a pack case structure provided with the side structure unit 400 and the filling member 500 according to the embodiment of the present invention will be briefly described as follows.

When manufacturing the battery pack 1, a manufacturer, etc. arranges the cooling unit 300 between the plurality of battery cells 100 and connects the battery cells 100 and the battery pack 100 through the side structure unit 400. It can be aligned to accommodate the cooling unit 300. In addition, the manufacturer, etc., within the opening space of the filling member injection holes 242 and 244 of the bus bar assembly 200 where the filling member injection holes 242 and 244 are formed on the upper side of the plurality of battery cells 100. Battery cells 100 may be electrically connected. Next, the manufacturer, etc., injects the upper side (+Z) of the battery cells 100 along the vertical direction (Z-axis direction) of the battery cells 100 through the opening spaces of the filling member injection holes 242 and 244. The filling member 500 can be injected and applied from the axial direction to the lower side (-Z axis direction).

Figure 24 is a diagram for explaining a car according to an embodiment of the present invention.

Referring to FIG. 24, the vehicle V may be an electric vehicle or a hybrid vehicle, and may include at least one battery pack 1 of the previous embodiment as an energy source.

In the case of this embodiment, the above-described battery pack 1 is provided in a compact structure with high energy density, so when mounted on the vehicle V, it is easy to implement a modular structure of a plurality of battery packs 1. , a relatively high degree of freedom of installation can be secured even in various internal space shapes of the vehicle V. That is, in this embodiment, the at least one battery pack 1 may be provided as a battery pack case structure that is easy to implement in a modular structure and has a high degree of freedom of installation.

In addition, the longitudinal direction of the at least one battery pack 1 is aligned with the longitudinal direction of the automobile so that the side structure unit 400 can protect the plurality of battery cells 100 in the event of a front or rear collision of the automobile. can be arranged vertically.

According to the various embodiments described above, a battery pack 1 capable of increasing energy density with a simpler structure and a vehicle V including the same can be provided.

In addition, according to the various embodiments described above, it is possible to provide a battery pack 1 that can increase manufacturing efficiency by reducing manufacturing cost and manufacturing time, and a vehicle V including the same.

In the above, preferred embodiments of the present invention have been shown and described, but the present invention is not limited to the specific embodiments described above, and may be used in the technical field to which the invention pertains without departing from the gist of the present invention as claimed in the claims. Of course, various modifications can be made by those with the knowledge, and these modifications should not be understood individually from the technical idea or perspective of the present invention.

Claims (20)

In the battery pack,
a plurality of battery cells;
A filling member filled in the space between the plurality of battery cells; and
A bus bar assembly electrically connected to the plurality of battery cells and having a filling member injection hole for injecting the filling member.
A battery pack comprising: According to paragraph 1,
The busbar assembly is,
A battery pack characterized in that it is electrically connected to the anode and cathode of the battery cells within the opening space of the filling member injection hole. According to paragraph 2,
The opening space of the filling member injection hole is,
A battery pack characterized in that it is provided so that both the positive and negative electrodes of the battery cells are exposed. According to paragraph 2,
The total area of the opening space is,
A battery pack, characterized in that the flow area of the filling member flowing between the battery cells is provided larger than the flow area of the filling member when the filling member is injected. According to paragraph 1,
The filling member is,
A battery pack having a predetermined viscosity and containing at least two substances. According to clause 5,
The filling member is,
A battery pack characterized in that it is prepared by mixing a predetermined resin and beads at a preset ratio. According to clause 5,
The predetermined resin is,
A battery pack characterized in that it is made of silicone resin. According to clause 5,
The predetermined bead is,
A battery pack characterized by being provided with a glass bubble. According to paragraph 2,
The busbar assembly is,
a pair of bus bar covers disposed on one side of the plurality of battery cells and on which the filling member injection hole is formed; and
A battery pack comprising a sub-bus bar provided between the pair of bus bar covers and connected to the anode and cathode of the battery cells. According to clause 9,
The pair of bus bar covers,
A battery pack characterized in that it is made of polyimide film. According to clause 9,
The sub bus bar is,
A battery pack provided as a single layer and inserted between the pair of bus bar covers. According to clause 11,
The sub bus bar is,
A bus bar bridge inserted between the pair of bus bar covers;
an anode connection portion extending from the bus bar bridge, exposed within the opening space of the filling member injection hole, and connected to anodes of the battery cells; and
A battery pack comprising a cathode connection portion extending from the bus bar bridge, exposed within the opening space of the filling member injection hole, and connected to the cathode of the battery cells. According to clause 12,
The filling member injection holes are provided in plural numbers,
The plurality of filling member injection holes are,
an anode bus bar hole exposing the anode connection portion and having an opening space larger than the size of the anode connection portion; and
A battery pack comprising a cathode bus bar hole that exposes the cathode connector and has an opening space larger than the size of the cathode connector. According to clause 12,
The filling member injection holes are provided in plural numbers,
The plurality of filling member injection holes each have,
A battery pack characterized in that both the anode connection part and the cathode connection part are exposed within one opening space. According to clause 14,
The plurality of filling member injection holes each have,
A battery pack characterized in that it has an opening space larger than the combined size of the anode connection portion and the cathode connection portion. According to clause 13,
The anode bus bar hole and the cathode bus bar hole are,
A battery pack characterized in that it is arranged oppositely with the bus bar bridge in between. In the method of manufacturing a battery pack,
Placing a cooling unit between a plurality of battery cells and aligning the battery cells and the cooling unit through a side structure unit to accommodate the cooling unit;
A step of electrically connecting the battery cells within the opening space of the filling member injection hole of the bus bar assembly where the filling member injection hole is formed on the upper side of the plurality of battery cells; and
Injecting and applying a filling member from the top to the bottom of the battery cells along the vertical direction of the battery cells through the opening space of the filling member injection hole.
A method of manufacturing a battery pack comprising: According to clause 17,
The filling member is,
A method of manufacturing a battery pack, characterized in that it is prepared by mixing a predetermined resin and beads at a preset ratio. According to clause 18,
The mixing ratio of the predetermined resin and beads is,
A method of manufacturing a battery pack, characterized in that it is prepared in a ratio of 100:60 (resin: glass bubble). A motor vehicle comprising at least one battery pack according to any one of claims 1 to 16.

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