KR20240012295A - Battery pack and device including the same - Google Patents

Abstract

A battery pack according to an embodiment of the present invention includes a plurality of battery cells in which battery cells each including a sealing portion are stacked in one direction, a cell cover covering at least a portion of the plurality of battery cells, and a sealing portion of the plurality of battery cells. It includes a venting passage formed between the unit and the cell cover, and an adhesive layer disposed on the inner surface of the venting passage.

Description

Battery pack and device including the same {BATTERY PACK AND DEVICE INCLUDING THE SAME}

The present invention relates to a battery pack and a device including the same, and more specifically, to a battery pack with improved energy density and cooling performance and enhanced safety and a device including the same.

In modern society, as the use of portable devices such as mobile phones, laptops, camcorders, and digital cameras becomes routine, the development of technologies in fields related to the above mobile devices is becoming more active. In addition, secondary batteries that can be charged and discharged are a way to solve air pollution from existing gasoline vehicles that use fossil fuels, and are used in electric vehicles (EV), hybrid electric vehicles (HEV), and plug-in hybrid electric vehicles ( As it is used as a power source for batteries such as P-HEV), the need for development of secondary batteries is increasing.

Currently commercialized secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries have the advantages of being able to charge and discharge freely, have a low self-discharge rate, and have high energy density. It's in the spotlight.

This lithium secondary battery includes an electrode assembly in which a positive electrode and a negative electrode plate each coated with a positive and negative electrode active material are disposed with a separator in between, and an exterior material, that is, a battery case, that seals and stores the electrode assembly together with an electrolyte.

In general, secondary batteries can be classified into can-type batteries in which the electrode assembly is built into a metal can and pouch-type batteries in which the electrode assembly is built in a pouch of an aluminum laminate sheet, depending on the shape of the exterior material.

Recently, battery packs have been widely used for driving or energy storage in medium to large-sized devices such as electric vehicles or energy storage systems. A conventional battery pack includes one or more battery modules inside the pack case and a control unit that controls charging and discharging of the battery pack, such as a BMS (Battery Management System). Here, the battery module is configured to include a plurality of battery cells inside a module case. That is, in the case of a conventional battery pack, a plurality of battery cells (secondary batteries) are stored inside the module case to form each battery module, and one or more of these battery modules are stored inside the pack case to form a battery pack.

In particular, pouch-type batteries have advantages in many aspects, such as being light in weight and requiring less dead space when stacked, but they are vulnerable to external shocks and have somewhat poor assembly properties. Therefore, it is common to manufacture a battery pack by first modularizing a number of cells and then storing them inside a pack case. As a representative example, in the case of a conventional battery pack, a plurality of battery cells are first stored inside a module case to form a battery module, and then one or more of these battery modules are stored inside the pack case. Moreover, conventional battery modules often stack multiple battery cells using various components such as a plastic stacking frame, also called a cartridge, plates at both ends of the cell stacking direction, and fastening members such as bolts. In many cases, the laminate formed in this way is again stored inside a module case and modularized.

However, such conventional battery packs may be disadvantageous in terms of energy density. Typically, in the process of modularizing multiple battery cells by storing them inside a module case, the volume of the battery pack may increase unnecessarily or the space occupied by the battery cells may decrease due to various components such as the module case or stacking frame. Furthermore, the space occupied by the components themselves, such as the module case or the stacking frame, as well as the storage space of the battery cells may be reduced to ensure assembly tolerances for these components. Therefore, in the case of conventional battery packs, there may be limitations in increasing energy density.

Additionally, conventional battery packs may be disadvantageous in terms of assembly. In particular, in order to manufacture a battery pack, first, a plurality of battery cells are modularized to form a battery module, and then the battery module is stored in a pack case. Therefore, there is a problem in that the battery pack manufacturing process becomes complicated. Moreover, as disclosed in the prior literature, the process and structure of forming a cell stack using stacking frames, bolts, plates, etc. can be very complex.

Additionally, in the case of conventional battery packs, since the module case is stored inside the pack case and the battery cells are stored inside the module case, there is a problem that it is difficult to ensure excellent cooling properties. In particular, when heat from battery cells stored inside the module case is discharged to the outside of the pack case through the module case, cooling efficiency may decrease and the cooling structure may become complicated.

In addition, capacity and output are improved by connecting multiple battery cells included in a conventional battery pack in series or parallel to each other to form a battery cell stack, but the heat generated from multiple battery cells in a narrow space within the battery module is added up. There is a problem that the overall temperature can rise more rapidly as a result.

The problem to be solved by the present invention is to provide devices including battery packs and automobiles with excellent energy density, assemblyability, and/or cooling properties.

In addition, the aim is to provide a battery pack with improved durability and safety by preventing continuous thermal runaway, and a device containing the same.

However, the problems to be solved by the embodiments of the present invention are not limited to the above-described problems, and other problems not described may be expanded to the extent that can be clearly understood by those skilled in the art from the description of the present invention.

A battery pack according to an embodiment of the present invention includes a plurality of battery cells in which battery cells each including a sealing portion are stacked in one direction; a cell cover covering at least a portion of the plurality of battery cells; a venting passage formed between the sealing portion and the cell cover of the plurality of battery cells; and an adhesive layer disposed on the inner surface of the venting passage.

The sealing portion may be a portion formed by sealing a side of the battery cell that faces the cell cover.

The cell cover includes a first side cover part and a second side cover part that cover the side surfaces of the plurality of battery cells, and an upper cover part that covers the upper part of the plurality of battery cells, and the sealing part covers the plurality of batteries. It can be placed at the top of the cell.

The upper cover part may be spaced apart from the sealing part.

The adhesive layer may be disposed on the inner surface of the upper cover part.

The adhesive layer may be further disposed on at least a portion of an inner surface of the first side cover portion and an inner surface of at least a portion of the second side cover portion.

The cell cover may cover the top and both sides of the plurality of battery cells and expose the bottom surface of the plurality of battery cells.

The sealing portion may be bent one or more times.

The cell cover may have any shape.

The cell cover may include stainless steel (SUS).

Each of the plurality of battery cells may be a pouch-type battery cell.

It may further include a pack case storing the plurality of battery cells and the cell cover in the internal space.

A device according to an embodiment of the present invention includes the at least one battery pack.

According to the present invention, continuous thermal runaway phenomenon can be prevented by preventing high-temperature particles emitted from each battery cell from scattering to the outside when gas or flame is generated.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

Figure 1 is a schematic perspective view showing some components of a battery pack separated according to an embodiment of the present invention.
Figure 2 is an exploded perspective view schematically showing a cell unit including a battery cell and a cell cover stored inside a battery pack according to an embodiment of the present invention.
Figure 3 is a perspective view showing the components of Figure 2 combined.
Figure 4 is a perspective view taken along section A of Figure 3;
Figure 5 is a front view of Figure 4.
Figure 6 is a diagram showing a cell unit in which an ignition phenomenon has occurred according to a comparative example.
FIG. 7 is a diagram showing venting gas being discharged in the y-axis direction of FIG. 3.
Figure 8 is a diagram showing a cell unit according to another embodiment of the present invention.

Hereinafter, with reference to the attached drawings, various embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. The present invention may be implemented in many different forms other than those described below, and the scope of the present invention is not limited by the embodiments described herein.

In order to clearly explain the present invention, parts that are not relevant to the description are omitted, and identical or similar components are given the same reference numerals throughout the specification.

In addition, since the size and thickness of each component shown in the drawings are arbitrarily enlarged or reduced for convenience of explanation, it is obvious that the content of the present invention is not limited to what is shown. In the drawings below, the thickness of each layer is enlarged to clearly express the various layers and regions. In the drawings below, the thicknesses of some layers and regions are exaggerated for convenience of explanation.

Additionally, when a part of a layer, membrane, area, plate, etc. is described as being “on” or “on” another part, this means that the corresponding part of the layer, membrane, area, plate, etc. is “directly above” the other part. In addition, it should be interpreted to include cases where there is another part in between. Conversely, when a part of a corresponding layer, membrane, region, plate, etc. is described as being "right on top" of another part, it may mean that there are no other parts in between. In addition, being "on" or "on" a reference part means being located above or below the reference part, and necessarily meaning being located "above" or "on" the direction opposite to gravity. Maybe not. Meanwhile, just as describing something as being “above” or “on” another part, explaining it as being “below” or “under” another part may also be understood with reference to the above-described content.

In addition, throughout the specification, when a part is said to "include" a certain component, this means that it may further include other components rather than excluding other components, unless specifically stated to the contrary.

Figure 1 is a schematic perspective view showing some components of a battery pack separated according to an embodiment of the present invention.

Figure 2 is an exploded perspective view schematically showing a cell unit including a battery cell and a cell cover stored inside a battery pack according to an embodiment of the present invention.

Figure 3 is a perspective view showing the components of Figure 2 combined.

Referring to FIGS. 1 to 3 , a battery pack 1000 according to an embodiment of the present invention includes a battery cell 100, a cell cover 200, and a pack case 600.

The battery cell 100 may be a pouch-type battery cell. That is, the battery cell 100 is a pouch-type secondary battery and may include an electrode assembly, an electrolyte, and a pouch exterior material.

In general, the pouch-type battery cell 100 can be manufactured through a process of injecting an electrolyte solution while storing the electrode assembly in a cell case and sealing the cell case. For example, the cell case can be sealed by adhering both ends of the battery cell 100 and one side connecting them.

A plurality of such battery cells 100 may be included in a battery pack. And, these plurality of battery cells 100 may be stacked in at least one direction. For example, referring to what is shown in FIG. 1, a plurality of battery cells 100 may be stacked and arranged in a horizontal direction, for example, in a left-right direction (x-axis direction in the drawing). Additionally, the plurality of battery cells 100 may be arranged in the front-back direction (y-axis direction in the figure) as shown in FIG. 1 .

Furthermore, the plurality of battery cells 100 may be arranged in a horizontal direction and in a plurality of rows in the left-right and horizontal directions. For example, referring to what is shown in FIG. 1, a plurality of battery cells 100 may be stacked in a form in which two cell rows are arranged in the left and right directions in the front-back direction.

The battery pack according to the present invention can employ various types of battery cells 100 known at the time of filing of the present invention, and therefore detailed description of the configuration of the battery cells 100 will be omitted.

The pack case 600 has an empty space formed therein and can accommodate a plurality of battery cells 100. For example, the pack case 600 may include an upper case 610 and a lower case 620, as shown in FIG. 1 . As a more specific example, the lower case 620 is configured in the form of a box with an open top and can accommodate a plurality of battery cells in the internal space. Additionally, the upper case 610 may be configured in the form of a cover that covers the upper opening of the lower case 620. At this time, the upper case 610 may be configured in the form of a box with an open bottom. Additionally, the cell cover 200 along with a plurality of battery cells 100 may be accommodated in the internal space of the pack case 600. The pack case 600 may be made of plastic or metal. In addition, the pack case 600 can adopt exterior materials of various battery packs known at the time of filing the present invention.

The cell cover 200 may be configured to surround the battery cell 100 in the internal space of the pack case. That is, the cell cover 200 may be configured to cover at least some of the battery cells 100 included in the battery pack. Furthermore, the cell cover may be provided to at least partially cover the battery cell 100.

Additionally, the cell cover 200 may be configured to support the stacked state of the plurality of battery cells 100 inside the pack case 600 through a structure that surrounds the battery cells. For example, a plurality of battery cells 100 may be stacked in the horizontal direction (x-axis direction of the figure) as shown in FIG. 1 . At this time, the cell cover 200 may be configured to stably maintain the stacked state of the plurality of battery cells 100 stacked in the horizontal direction.

According to this aspect of the present invention, a plurality of battery cells 100 can be directly seated and stored inside the pack case 600 without a module case. In particular, in the case of the battery cells 100, the exterior material is made of a soft material, so it is vulnerable to external shock and has low hardness. Therefore, it is not easy to store the battery cell 100 itself inside the pack case 600 without storing it in the module case. However, in the case of the present invention, the plurality of battery cells 100 are combined with the cell cover 200 in a state in which at least a portion is surrounded by the cell cover 200, and are directly stored inside the pack case 600, The stacked state can be maintained stably.

Therefore, according to this aspect of the present invention, there is no need to additionally provide the battery pack 1000 with a module case, a stacking frame, or fastening members such as bolts for maintaining the stacked state of the cells. Accordingly, the space occupied by other components, such as a module case or a stacking frame, or the resulting space for securing tolerances can be eliminated. Therefore, since the battery cells can occupy more space as the space removed, the energy density of the battery pack can be further improved.

Additionally, according to this aspect of the present invention, since a module case, stacking frame, bolts, etc. are not provided, the volume and weight of the battery pack can be reduced and the manufacturing process can be simplified.

Additionally, according to this aspect of the present invention, handling of the battery cell 100 may become easier. For example, when storing a plurality of battery cells 100 inside a pack case, the battery cells 100 can be held by a jig or the like. At this time, the jig may not directly hold the battery cell 100, but may hold the cell cover 200 surrounding the battery cell 100. Accordingly, damage or breakage of the battery cell 100 caused by the jig can be prevented.

Additionally, according to this aspect of the present invention, the cell cover 200 is coupled to the battery cell 100, so that the battery cell 100 can be effectively protected without a module case.

The cell cover 200 may be made of various materials to ensure rigidity. In particular, the cell cover 200 may be made of a metal material. In the case of this metal material, the stacked state of the battery cells can be maintained more stably and the battery cells can be more safely protected from external shock. In particular, the cell cover 200 may be made of steel, or even stainless steel (SUS). For example, the cell cover 200 may be entirely made of SUS material.

In this way, when the cell cover 200 is made of a steel material, it has excellent mechanical strength and rigidity, so the stacked state of the battery cells 100 can be more stably supported. Additionally, in this case, it is possible to more effectively prevent damage or breakage of the battery cell 100 from external impacts, such as acicular bodies. Additionally, in this case, handling of the battery cell may become easier.

Additionally, as in the above embodiment, when the cell cover 200 is made of a steel material, due to its high melting point, when a flame occurs from the battery cell 100, the overall structure can be stably maintained. In particular, in the case of steel material, the melting point is higher than that of aluminum material, so it does not melt even with flame emitted from the battery cell 100 and its shape can be stably maintained. Accordingly, excellent flame propagation prevention and delay effects between battery cells 100, venting control effects, etc. can be secured.

The cell cover 200 may be configured to surround one or more battery cells 100. For example, as shown in FIGS. 2 and 3, one cell cover 200 may be configured to cover one battery cell 100 or a plurality of battery cells 100. In this case, the cell cover 200 is individually coupled to each battery cell 100 among the plurality of battery cells 100, or the cell cover 200 is connected to two or more battery cells 100 together. It can be configured to surround.

The cell cover 200 may be at least partially adhered to the outer surface of the battery cell 100. For example, the cell cover 200 may have its inner surface adhered to the receiving portion of the battery cell 100.

One or more cell covers 200 may be included in the battery pack. In particular, the cell cover 200 may be configured to group and unitize a plurality of battery cells 100 included in the battery pack. In this case, one cell cover 200 can be said to constitute one cell unit 10. Additionally, one cell unit 10 may include one or more battery cells 100. A battery pack may include a plurality of cell units, and in this case, it can be said that a plurality of cell covers 200 are included in the battery pack. For example, when the cell cover 200 is configured to surround one battery cell 100, the battery pack may include the same number of cell covers 200 as the number of battery cells 100. As another example, when the cell cover 200 is configured to surround two or more battery cells 100, the battery pack may include a smaller number of cell covers 200 than the number of battery cells 100.

The cell cover 200 may be configured to support a plurality of battery cells 100 in an upright state. As shown in FIG. 2, each battery cell 100 has two wide surfaces, and the corners of the large surfaces may have sealing portions or folded portions of the pouch exterior material. Therefore, it is generally difficult to stack the battery cells 100 in an upright direction. However, in the battery pack according to the present invention, the cell cover 200 may be configured to surround one or more battery cells 100 and support the upright state, that is, the standing state, of the wrapped battery cells 100. there is.

In particular, the cell cover 200 may be configured so that a plurality of battery cells 100 can be stacked horizontally while standing vertically. For example, as in the embodiment shown in FIGS. 1 to 3, a plurality of cell covers 200 are stacked on each other in the horizontal direction, and each cell cover 200 includes one or more battery cells 100. It may be configured in an enveloping form. In this case, the cell cover 200 can stably maintain a configuration in which the plurality of battery cells 100 are stacked side by side in the horizontal direction when each is erected.

In particular, the cell cover 200 can be configured to stand on its own in the internal space of the pack case 600. In other words, the cell cover 200 can be configured to maintain an upright position on its own without the help of other components included in the battery pack, such as the pack case 600 or the battery cell 100.

For example, the cell cover 200 may be directly seated on the bottom surface of the lower case 620 in the embodiment of FIG. 1 . At this time, a portion of the cell cover 200 and the lower end of the cell cover 200 may be seated in direct contact with the bottom surface of the lower case 620. At this time, a thermal resin layer 626 may be formed on the bottom surface of the lower case 620. The thermal resin layer 626 may transfer heat to the heat sink so that the heat generated in the battery cell 100 is dissipated through the heat sink (not shown). Although not shown, a heat sink may be formed under the thermal resin layer 626. For example, a heat sink may be formed on the bottom of the lower case 620, and a thermal resin layer 626 may be applied to the upper surface of the heat sink. The thermal resin layer 626 has adhesive properties, so that the cell cover 200 and/or the battery cell 100 can be coupled to the bottom surface of the lower case 620 or a heat sink. The thermal resin layer 626 can maintain the upright state of the battery cell 100 and the cell cover 200 more stably.

In addition, when the lower end of the cell cover 200 is seated in this way, the cell cover 200 may be configured to maintain the seated state stably. At this time, when the cell cover 200 is made of a metal material with excellent rigidity such as steel, especially a SUS material, the self-standing state can be maintained more stably. Therefore, in this case, the upright state of the battery cell 100 can be more reliably supported.

The cell cover 200 may be configured to partially surround the battery cell so that at least one side of the wrapped battery cell is exposed to the outside. That is, the cell cover 200 may be configured to only partially cover the battery cell 100, rather than completely covering the entire battery cell 100. In particular, the cell cover 200 may be configured so that at least one side of the battery cell is exposed toward the pack case.

For example, referring to the embodiment of FIGS. 2 and 3, the cell cover 200 is configured to surround one battery cell 100, and includes the wrapped battery cell 100, that is, accommodated in the internal space. The lower portion of the battery cell 100 may not be surrounded by the cell cover 200. Accordingly, the lower part of the battery cell 100 is exposed toward the pack case 600 and can directly face the pack case 600. In particular, referring to the embodiment of FIG. 1, the lower part of the battery cell 100 may be exposed toward the bottom surface of the lower case 620.

According to this embodiment of the present invention, the cooling performance of the battery pack can be secured more effectively. In particular, according to the above embodiment, the battery cell 100 and the pack case 600 may be in direct contact with each other. Accordingly, the heat emitted from each battery cell 100 is directly transferred to the pack case 600, and cooling performance can be improved. Additionally, in this case, since a separate cooling structure does not need to be provided between the battery cell 100 and the pack case 600, efficient cooling performance can be implemented. In this case, there may not be space between the battery cells 100 for a coolant such as air to flow in.

Meanwhile, in the battery pack according to the present invention, TIM (Thermal Interface Material) may be interposed to increase heat transfer performance between different components. For example, TIM may be filled between the battery cell 100 and the cell cover 200, between the cell cover 200 and the pack case 600, and/or between the battery cell 100 and the pack case 600. You can. In this case, the cooling performance of the battery pack, such as dual cooling performance, can be further improved.

In particular, the cell cover 200 may be configured to surround an edge portion that is not provided with an electrode lead among several edge portions of the battery cell 100 accommodated therein. For example, referring to the embodiment shown in FIG. 2, the battery cell 100 may be provided with two electrode leads 110, that is, a positive electrode lead and a negative electrode lead. At this time, the two electrode leads may be located at the front edge and the rear edge, respectively. At this time, the cell cover may be configured to surround one of the remaining two edge parts excluding the front edge part and the rear edge part.

Referring to Figures 2 and 3, the battery cell 100 may be said to be formed in an approximately hexahedron. Additionally, electrode leads 110, that is, a negative electrode lead and a positive electrode lead, may be formed on two of the six surfaces. Additionally, the cell cover 200 is provided to cover at least a portion of three of the four sides of the six-sided battery cell 100 except for the two sides on which the electrode leads 110 are formed.

According to this embodiment of the present invention, the discharge direction of flame, etc. can be directed to the exposed side of the cell cover 200. For example, according to the embodiment, the front and rear sides of the cell cover 200 where the electrode lead 110 is located are open, so flames, etc. can be discharged in these open directions. In particular, when the cell cover 200 is configured with the front and back open as described above, side directional venting can be easily implemented.

According to this embodiment of the present invention, a structure that supports and protects one or more battery cells can be easily implemented as a single cell cover 200. In particular, according to the above embodiment, the lower edge portion may be in direct contact with the pack case 600 without being surrounded by the cell cover 200. Accordingly, heat from the battery cell 100 wrapped by the cell cover 200 can be quickly and smoothly discharged toward the pack case 600 below. Accordingly, the cooling performance of the battery pack can be secured more effectively.

In particular, this configuration can be implemented more effectively when cooling is mainly performed at the bottom of the pack case 600. For example, in the case of a battery pack mounted on an electric vehicle, cooling may occur mainly at the bottom of the pack case 600 because it is mounted on the lower part of the vehicle body. At this time, as in the above embodiment, when the lower edge portion of each battery cell 100 is in contact with the pack case, heat is quickly transferred from each battery cell 100 to the pack case, and cooling performance is further improved. You can.

In addition, according to the above embodiment, when high-temperature gas or flame is discharged from the battery cell 100 in a situation such as thermal runaway, it is possible to effectively prevent the discharged gas or flame from heading toward the upper side. In particular, when the occupant is located on the upper side of the battery pack, such as in an electric vehicle, according to the above embodiment, it is possible to suppress or delay gas or flame from heading toward the occupant.

Referring to Figures 2 and 3, the cell cover 200 can be said to be formed in a shape roughly similar to the letter n. In addition, the cell cover 200, through this shape, can be said to be configured to cover the front and rear sides where the electrode leads protrude, and other parts of the battery cell 100 accommodated therein, except for the lower side. You can. That is, the cell cover 200 may be provided to cover the outer and upper sides of the storage portion of the battery cells accommodated therein.

More specifically, the cell cover 200 may include an upper cover part 210, a first side cover part 220, and a second side cover part 230, as shown in FIG. 2.

Here, the upper cover part 210 may be configured to surround the upper part of the battery cell 100 accommodated therein. In particular, the upper cover portion 210 may be configured to be in contact with or spaced apart from the upper edge portion of the battery cell 100. Additionally, the upper cover portion 210 may be configured in a planar shape. In this case, the upper cover portion 210 is formed in a straight horizontal cross-section and can surround the upper edge portion of the battery cell 100 in a straight line from the outside.

The first side cover part 220 may be configured to extend downward from one end of the upper cover part 210. For example, the first side cover part 220 may be configured to extend long from the left end of the upper cover part 210 in the downward direction (-Z axis direction in the drawing). Furthermore, the first side cover portion 220 may be formed in a planar shape. At this time, the first side cover part 220 may be configured in a bent form from the upper cover part 210.

Additionally, the first side cover portion 220 may be configured to surround the outside of one side of the storage portion of the battery cell 100 accommodated therein. For example, when one battery cell 100 is accommodated in the cell cover 200, the first side cover portion 220 may be configured to surround the left surface of the housing portion of the accommodated battery cell 100 from the left. You can. Here, the first side cover portion 220 may be in direct contact with the outer surface of the storage portion.

The second side cover part 230 may be positioned to be spaced apart from the first side cover part 220 in the horizontal direction. And, the second side cover part 230 may be configured to extend downward from the other end of the upper cover part 210. For example, the second side cover part 230 may be configured to extend downward from the right end of the upper cover part 210. Moreover, the second side cover part 230 may also be configured in a planar shape like the first side cover part 220. At this time, the second side cover portion 230 and the first side cover portion 220 may be said to be arranged parallel to each other while being spaced apart in the horizontal direction.

And the second side cover portion 230 may be configured to surround the outside of the other side storage portion of the battery cell 100 accommodated therein. For example, when one battery cell 100 is accommodated in the cell cover 200, the second side cover portion 230 may be configured to surround the right surface of the housing portion of the accommodated battery cell 100 from the right side. You can. Here, the second side cover portion 230 may be in direct contact with the outer surface of the storage portion.

In the above embodiment, the internal space may be limited by the upper cover part 210, the first side cover part 220, and the second side cover part 230. Additionally, the cell cover 200 can accommodate one or more battery cells in this limited internal space.

Additionally, in the above embodiment, lower ends of the first side cover portion 220 and the second side cover portion 230 may contact the bottom surface of the pack case 600. In particular, the contact configuration between the lower ends of the first side cover portion 220 and the second side cover portion 230 and the pack case 600 has a shape that extends long in the front-back direction (y-axis direction in the drawing). It can be formed as According to this embodiment, the self-supporting configuration of the cell cover 200, which can maintain the battery cell 100 accommodated therein in an upright state, can be implemented more stably.

Moreover, the first side cover part 220 and the second side cover part 230 may have the same height. That is, the first side cover part 220 and the second side cover part 230 may have the same length extending downward from the upper cover part 210. In this case, the self-standing configuration of the cell cover 200 can be more easily achieved.

Meanwhile, to describe again the cell cover 200 and the battery cell 100 according to an embodiment of the present invention, the upper cover portion 210 may face the upper edge portion of the battery cell 100, and the first It can surround the upper edge portion together with the side cover portion 220 and the second side cover portion 230.

In addition, the cross-sectional area of the first side cover part 220 and the second side cover part 230 is larger than the cross-sectional area of the battery cell 100 where the first side cover part 220 and the second side cover part 230 face each other. It is provided in a large size to prevent the storage part from being exposed to the outside, ensuring maximum safety.

Meanwhile, the battery cell 100 may include a sealing portion 240 (see FIG. 4). The sealing portion 240 (see FIG. 4) may be a portion of the battery cell 100 formed by sealing one side of the battery cell 100 that faces the cell cover 200. The sealing portion 240 (see FIG. 4) may be sealed by a method such as heat fusion, and may be bent one or more times to improve sealing performance. For example, the sealing portion 240 (see FIG. 4) may be a double side folded portion.

In the embodiment of FIG. 2, the upper edge portion may be a double side folded portion as the sealing portion 240 (see FIG. 4) of the battery cell 100. The lower edge portion may be an unsealed portion of the battery cell 100.

Here, the cell cover 200 may be configured to surround the battery cell 100, covering at least a portion of the sealed portion, and exposing at least a portion of the unsealed portion to the outside without enclosing it. For example, referring to the embodiment of FIG. 2, the cell cover 200 may be configured to cover the upper edge portion, which is part of the sealing portion of the battery cell 100. In this case, the battery cell 100 accommodated inside the cell cover 200 can be said to be configured so that the upper edge portion, which is a sealing portion, faces the upper cover portion 210. Additionally, the cell cover 200 may cover the battery cell 100 so that the lower edge portion, which is an unsealed portion of the battery cell 100, is exposed to the outside. In this case, it can be said that the lower edge portion of the battery cell 100, which is an unsealed portion, is disposed on the open surface of the cell cover 200.

In the battery cell 100, the upper edge portion, which is a sealed portion, may be relatively more vulnerable to the discharge of high-temperature gas or flame than the lower edge portion, which is an unsealed portion. However, according to the above embodiment, the upper edge portion, which is the sealing portion, is disposed to face the upper cover portion 210, which may be more advantageous for directional venting.

In addition, in the battery cell 100, the lower edge portion, which is an unsealed portion, has a relatively larger cross-sectional area than the upper edge portion, which is a sealed portion, and is provided in a flat shape so that it can be placed on the open surface of the cell cover 200, as shown in FIG. 1 Cooling efficiency can be increased by direct contact with the thermal resin layer 626.

Furthermore, when the lower case 620 is seated on one side of the car body, the first side cover part 220 and the second side cover part 230 may extend from the upper cover part 210 toward one side of the car body, The upper edge portion may be disposed farther from one side of the vehicle body than the lower edge portion. That is, when the lower case 620 is seated on one side of the vehicle body, the cell cover 200 may be configured so that the side disposed relatively close to the one side of the vehicle body is open.

Conversely, when the upper case 610 is seated on one side of the vehicle body, the first side cover portion 220 and the second side cover portion 230 may extend away from the upper cover portion 210 and one side of the vehicle body. , the upper edge portion may be disposed closer to one side of the vehicle body than the lower edge portion. That is, when the upper case 610 is seated on one side of the vehicle body, the cell cover 200 may be configured so that the side located relatively far from the one side of the vehicle body is open.

That is, the arrangement of the cell cover 200 and the battery cell 100 can be set in various ways depending on the relationship with the vehicle body, pack case 600, and components other than the pack case 600 arranged on the vehicle body.

Meanwhile, in the above embodiment, the cell cover 200 is shown and described focusing on an n-shaped configuration, but the cell cover 200 may be configured in various other shapes. For example, the cell cover 200 may be formed in various other shapes such as I-shape, U-shape, L-shape, etc.

Figure 4 is an exploded perspective view schematically showing a partial configuration of a battery pack according to an embodiment of the present invention.

Referring to FIG. 2, the battery pack according to the present invention may further include a busbar assembly 300. Here, the bus bar assembly 300 may be configured to electrically connect a plurality of battery cells 100 to each other. For example, as shown in FIG. 2, the bus bar assembly 300 is coupled to the electrode lead 110 of the plurality of battery cells 100, and electrically connects the plurality of battery cells 100 in series and /Or it can be connected in parallel. The busbar assembly 300 includes a busbar terminal made of an electrically conductive material such as copper or aluminum and in direct contact with the electrode lead 110, and a busbar housing made of an electrically insulating material such as plastic and supporting the busbar terminal. can be provided.

Moreover, when the electrode leads 110 are provided on both sides of the battery cell 100, the bus bar assembly 300 may also be included on both sides where the electrode leads 110 are provided. For example, as shown in FIG. 2, when the electrode lead 110 protrudes both on the front side (y-axis direction in the drawing) and on the rear side (-y-axis direction in the drawing), the bus bar assembly 300 Additionally, it can be located both anteriorly and posteriorly.

The bus bar assembly 300 may be combined with one or more cell covers 200. At this time, the bus bar assembly 300 may be coupled to the end of one cell cover 200. At this time, one cell cover 200 may accommodate one or multiple battery cells 100.

The busbar assembly 300 may be coupled to the cell cover 200 in various ways. For example, the bus bar assembly 300 may be coupled and fixed to the cell cover 200 through various fastening methods such as adhesive, welding, fitting, hook, bolting, and riveting.

Referring to Figures 2 and 3, the battery pack 1000 according to the present invention may further include an insulating cover part 350 and an end plate 400. The insulating cover portion 350 is made of an electrically insulating material, prevents the bus bar assembly 300 from being exposed to the outside by the end plate 400, and secures and maintains electrical insulation.

The end plate 400 covers the front and rear surfaces of the plurality of battery cells 100 and may be combined with the cell cover 200. The end plate 400 includes a first end plate 410 disposed on the front side of the battery cell 100 (y-axis direction in the drawing) and a first end plate 410 disposed on the rear side of the battery cell 100 (-y-axis direction in the drawing). It may include a second end plate 410.

The end plate 400 may be sealed and coupled to the cell cover 200 through welding.

At this time, the end plate 400 can secure the bus bar assembly 300 and the insulating cover portion 350 to secure the structural stability of the cell unit 10. Meanwhile, a hole through which the insulating cover portion 350 is exposed may be formed in the end plate 400, and directional venting may be induced in some cases through the hole.

Below, the venting passage and adhesive layer included in the battery pack 1000 according to this embodiment will be described in more detail.

Figure 4 is a perspective view taken along section A of Figure 3;

Figure 5 is a front view of Figure 4.

Referring to FIGS. 4 and 5 , an air gap may exist between the top of the cell cover 200 and the battery cell 100. A venting passage (VP, see FIG. 7) is formed through this air gap, through which gas generated in the battery cell 100 can move. In particular, since the sealing portion 240 is formed on the upper edge portion of the battery cell 100, high-temperature gas or flame can be discharged relatively more easily than the unsealed lower edge portion. If gas or flame is generated, it may be discharged as high-temperature gas and sparks through the venting passage (VP, see FIG. 7), and ignition may occur when the sparks come into contact with external oxygen, etc. Accordingly, in order to solve the above-described problem, the battery pack of this embodiment may include an adhesive layer 250 that prevents sparks, that is, high-temperature particles, from scattering to the outside. The adhesive layer 250 may be disposed on the inner surface of the space between the cell cover 200 and the battery cell 100. Specifically, the adhesive layer 250 may be disposed on the inner surface of the upper cover portion 210. Additionally, the adhesive layer 250 may be further disposed on at least a portion of the inner surface of the first side cover portion 220 and at least a portion of the inner surface of the second side cover portion 230. For example, the adhesive layer 250 is the inner surface of the upper cover part 210, the inner surface of a portion of the first side cover part 220 extending downward from one end of the upper cover part 210, and the upper cover part 210. ) may be disposed on the inner surface of a portion of the second side cover portion 230 extending downward from the other end. In particular, by forming a relatively large adhesive layer between the sealing part 240 and the upper cover part 210, it is possible to capture more sparks.

When the adhesive layer 250 is formed on the cell unit 10, particles moving along the air gap, which is a venting passage, when the battery cell 100 is ignited, can be attached to the adhesive layer 250, and through this, the particles can be attached to the cell unit ( 10) Scattering to the outside can be prevented. When the emission of high-temperature particles, that is, sparks, is limited by the adhesive layer 250, the possibility of sparks coming into contact with external oxygen is reduced, and thus additional thermal runaway phenomenon can be prevented.

The adhesive layer 250 may be attached to the inside of the venting passage in the form of a layer, or may be applied in liquid form and then formed as a layer.

The adhesive layer 250 may include an adhesive material. The adhesive material that can be used in the adhesive layer 250 can be of any type as long as it has adhesiveness that allows particles to attach. Examples of adhesive materials include those containing atrylate or silicone, and the above-mentioned adhesive materials include ester rubber, phenol resin, or other substances used as auxiliaries, or low molecular substances such as castor oil or polyisobutylene. Can be further mixed.

The adhesive layer 250 may be provided in the venting passage. The venting flow path may extend along the y-axis direction shown in Figures 2 and 3, and when directional venting is induced through the hole in the end plate 400, gas and flame are discharged along the venting flow path, and at this time, the adhesive layer ( If the emission of high-temperature particles, that is, sparks, is limited by 250), the possibility of sparks coming into contact with external oxygen is reduced, and thus additional thermal runaway phenomenon can be prevented.

Figure 6 is a diagram showing a cell unit in which an ignition phenomenon has occurred according to a comparative example.

FIG. 7 is a diagram showing venting gas being discharged in the y-axis direction of FIG. 3.

Referring to FIG. 6, the cell unit may include a venting passage formed between the cell cover 21 and the battery cell 1. The battery cell (1) can generate a large amount of heat during the charging and discharging process, and if its temperature rises higher than the appropriate temperature for reasons such as overcharging, its performance may deteriorate, and if the temperature rise is excessive, it may explode or ignite. . When the battery cell (1) ignites, the internal materials of the cell may be ejected along with high-temperature flammable gas to the outside. These internal materials are mainly materials such as C, Cu, Al, Ni, Co, Mg, and Li. It is ejected in the form of particles, that is, sparks.

Meanwhile, these sparks generate an ignition phenomenon when they come in contact with flammable gases or external oxygen discharged together, so they can cause continuous thermal runaway inside and outside the battery pack including the battery cell 1.

Referring to FIG. 7 , the cell unit 10 according to this embodiment may include a venting passage VP formed between the battery cell 100 and the upper cover portion 210. The venting passage VP may be used to discharge gas generated from the battery cell 100 to the outside of the cell cover 200. The venting passage VP may be formed in the space between the cell cover 200 and the battery cell 100. A venting portion discharging internal gas of the battery cell 100, for example, a hole of the end plate 400 described in FIGS. 2 and 3 may be located at one end of the venting passage VP. Flames, gases, etc. discharged from each battery cell 100 into the venting passage (VP) may move along the venting passage (VP) and be discharged to the outside through an outlet (not shown) provided in the cell unit 10. .

As shown in FIG. 7, when the battery cell 100 ignites, particles moving along the venting passage VP may attach to the adhesive layer 250, and through this, the particles scatter out of the cell unit 10. This can be prevented. When the emission of high-temperature particles, that is, sparks, is limited by the adhesive layer 250, the possibility of sparks coming into contact with external oxygen is reduced, and thus additional thermal runaway phenomenon can be prevented.

Figure 8 is a diagram showing a cell unit according to another embodiment of the present invention.

The embodiment of FIG. 8 is a modified version of the embodiment of FIG. 5 , and the cell unit 20 according to this embodiment may further include a heat transfer member 260 covering the top of the battery cell 100. The heat transfer member 260 may be formed by applying a silicon-based material or may be formed as a thermally conductive pad. The adhesive layer 250 may be formed between the heat transfer member 260 and the upper cover portion 210. The adhesive layer 250 is formed on the inner surface of the upper cover part 210, the inner surface of a portion of the first side cover part 220 extending downward from one end of the upper cover part 210 to the heat transfer member 260, and the upper cover part. An adhesive layer 250 may be formed on the inner surface of a portion of the second side cover portion 230 extending downward from the other end of 210 to the heat transfer member 260 . However, the formation position of the adhesive layer 250 is not limited to this, and may be formed by being directly applied or attached to the upper surface of the heat transfer member 260.

In addition to the differences described above, all of the information described in FIG. 5 is applicable to the present embodiment.

Meanwhile, although not specifically mentioned above, the battery pack according to an embodiment of the present invention adds a battery management system (BMS) and/or a cooling device that manages the temperature or voltage of the battery, etc. It can be included as .

The battery pack according to an embodiment of the present invention can be applied to various devices. For example, a device to which a battery pack is applied may be a means of transportation such as an electric bicycle, electric car, or hybrid car. However, the above-described devices are not limited thereto, and the battery pack according to this embodiment can be used in various devices other than the above-described examples, which also fall within the scope of the present invention.

In this embodiment, terms indicating directions such as front, back, left, right, up, and down are used, but these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer. .

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims are also possible. It falls within the scope of invention rights.

10, 20: cell unit
VP: Venting Euro
100: battery cell
200: Cell cover
210: upper cover part
220: first side cover portion
230: Second side cover part
240: Sealing part
250: Adhesive layer
260: Thermal resin layer
300: Busbar assembly
350: Insulating cover part
400: End plate
600: pack case
610: upper case
620: lower case
1000: Battery pack

Claims (13)

A plurality of battery cells, each of which includes a sealing portion, stacked in one direction;
a cell cover covering at least a portion of the plurality of battery cells;
a venting passage formed between the sealing portion and the cell cover of the plurality of battery cells; and
A battery pack including an adhesive layer disposed on the inner surface of the venting passage. In paragraph 1:
The sealing portion is a battery pack formed by sealing one side of the battery cell facing the cell cover. In paragraph 1:
The cell cover includes a first side cover part and a second side cover part covering side surfaces of the plurality of battery cells, and an upper cover part covering the top of the plurality of battery cells,
The sealing portion is a battery pack disposed on top of the plurality of battery cells. In paragraph 3,
The upper cover part is a battery pack spaced apart from the sealing part. In paragraph 3,
The adhesive layer is a battery pack disposed on the inner surface of the upper cover portion. In paragraph 5,
The adhesive layer is further disposed on an inner surface of at least a portion of the first side cover portion and an inner surface of at least a portion of the second side cover portion. In paragraph 1:
The cell cover covers the top and both sides of the plurality of battery cells and exposes the bottom surface of the plurality of battery cells. In paragraph 1:
A battery pack in which the sealing portion is bent one or more times. In paragraph 1:
A battery pack in which the cell cover has an integrated shape. In paragraph 1:
The cell cover is a battery pack containing stainless steel (SUS). In paragraph 1:
A battery pack in which each of the plurality of battery cells is a pouch-type battery cell. In paragraph 1:
A battery pack further comprising a pack case storing the plurality of battery cells and the cell cover in an internal space. A device comprising the battery pack according to claim 1.