KR20230097863A - Battery pack and device including the same - Google Patents

Abstract

A battery pack according to an embodiment of the present invention includes a battery cell stack including a plurality of battery cells and a pack frame accommodating the battery cell stack, and between the battery cell stack and the pack frame, the battery A venting passage for discharging gas generated from the cells is provided, mesh members are formed on the front and rear surfaces of the pack frame, and when the battery pack is ignited, the gas generated by the ignition moves through the venting passage, It is discharged by passing through the mesh member.

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 particularly, to a battery pack capable of minimizing the outflow of sparks due to internal ignition and a device including the same.

As the use of portable devices such as mobile phones, laptop computers, camcorders, and digital cameras has become commonplace in modern society, development of technologies in fields related to the above mobile devices has become active. In addition, a secondary battery capable of charging and discharging is a method for solving air pollution such as existing gasoline vehicles using fossil fuels, electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles ( P-HEV), etc., 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. is getting the most attention.

On the other hand, in the case of a secondary battery used in a small device, 2-3 battery cells are mainly used, but in the case of a secondary battery used in a medium or large device such as an automobile, a medium or large battery module or battery in which a plurality of battery cells are electrically connected pack is used.

1 is a diagram showing a gas discharge path when internal ignition of a conventional battery pack occurs.

The battery cells installed in the battery pack 10 may generate a large amount of heat during charging and discharging, and when the temperature of the battery cells becomes higher than an appropriate temperature due to overcharging or the like, the battery cells may explode or ignite. On the other hand, when the battery cell is ignited, the internal material of the cell may be ejected along with the high-temperature inflammable gas. It erupts in the form of sparks. Such sparks may promote a continuous thermal runaway phenomenon within the battery pack 10, and when discharged to the outside, may cause an additional ignition phenomenon by contacting an inflammable gas or external oxygen.

As shown in FIG. 1 , gas and spark generated when the battery cell is ignited may move within the pack frame of the battery pack 10 and be discharged to both ends of the pack frame. Sparks lose energy and are converted into particles in the process of being discharged to the outside of the battery pack 10, but the gas discharge path formed in the conventional battery pack 10 is rather short for sparks to be converted into particles, and the battery pack 10 ), there was a problem in that the spark easily leaked to the outside because a separate structure for limiting the discharge of the spark was not formed in the frame of the frame.

An object to be solved by the present invention is to provide a battery pack having improved durability and safety by preventing external ignition caused by a spark, and a device including the same.

However, the problems to be solved by the embodiments of the present invention are not limited to the above problems and can be variously extended within the scope of the technical idea included in the present invention.

A battery pack according to an embodiment of the present invention includes a battery cell stack including a plurality of battery cells and a pack frame accommodating the battery cell stack, and between the battery cell stack and the pack frame, the battery A venting passage for discharging gas generated from the cells is provided, mesh members are formed on the front and rear surfaces of the pack frame, and when the battery pack is ignited, the gas generated by the ignition moves through the venting passage, It is discharged by passing through the mesh member.

The mesh member may be located at the center of the front and rear surfaces of the pack frame.

The mesh member may include two meshes overlapping each other.

The battery cell stack may include a plurality of battery cells stacked in a direction from the front side of the pack frame to the rear side.

A venting guide pipe may be positioned in the venting passage.

The venting guide pipe may correspond to a side surface of the battery pack.

The venting guide tube may have a tube shape extending along the stacking direction of the battery cells.

The venting guide pipe may include a plurality of holes connected to electrode leads of the battery cell.

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

According to embodiments, the battery pack of the present invention can minimize the propagation of an ignition phenomenon to the outside of the battery pack by preventing the emission of sparks.

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.

1 is a diagram showing a gas discharge path when internal ignition of a conventional battery pack occurs.
2 is a perspective view of a battery pack according to an embodiment of the present invention.
3 is a perspective view illustrating a gas discharge path when the battery pack is ignited according to an embodiment of the present invention.
4 is a top view illustrating a gas discharge path when the battery pack is ignited according to an embodiment of the present invention.
5 is a view showing the front and rear surfaces of a pack frame included in a battery pack according to an embodiment of the present invention.
6 is examples of mesh members included in a battery pack according to an embodiment of the present invention.
7 illustrates an example in which a mesh member included in a battery pack according to an embodiment of the present invention is provided as two mesh sheets.
8 is a view showing an example in which a venting guide tube is provided in a battery pack according to an embodiment of the present invention.
9 is a perspective view of a venting guide tube included in the battery pack of FIG. 8 .
10 is a cross-sectional view taken along the AA axis of FIG. 9 .

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out 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 describe the present invention, parts irrelevant to the description are omitted, and the same reference numerals are assigned to the same or similar components 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 description, it is obvious that the contents of the present invention are not limited to those shown. In the following drawings, the thickness of each layer is shown enlarged in order to clearly express various layers and regions. Also, in the following drawings, for convenience of description, thicknesses of some layers and regions are exaggerated.

Also, when a portion of a layer, film, region, board, etc. is described as being "on" or "on" another portion, this means that the layer, film, region, board, etc. portion in question is "directly on" the other portion. In addition, it should be construed as including the case where there is another part in between. Conversely, when a part of a corresponding layer, film, region, plate, etc. is described as being "directly on" another part, it may mean that there is no other part in between. In addition, to be "on" or "on" a reference part means to be located above or below the reference part, and to necessarily be located "above" or "on" in the opposite direction of gravity does not mean It may not be. On the other hand, similar to the description of being "above" or "on" another part, the description of being "below" or "below" another part will also be understood with reference to the above-described content.

In addition, since the upper/lower surface of a specific member can be determined differently depending on which direction it is based, 'upper surface' or 'lower surface' is defined as meaning two surfaces facing each other on the z-axis in the entire specification. . In addition, the side surface may mean a surface perpendicular to the upper or lower surface.

In addition, throughout the specification, when a certain part "includes" a certain component, it means that it may further include other components without excluding other components unless otherwise stated.

In addition, throughout the specification, when it is referred to as "planar", it means when the corresponding part is viewed from above, and when it is referred to as "cross-section", it means when the cross section of the corresponding part cut vertically is viewed from the side.

Hereinafter, a battery pack according to an embodiment of the present invention will be described.

2 is a perspective view of a battery pack according to an embodiment of the present invention. 3 is a perspective view illustrating a gas discharge path when the battery pack is ignited according to an embodiment of the present invention. 4 is a top view illustrating a gas discharge path when the battery pack is ignited according to an embodiment of the present invention. 5 is a view showing the front and rear surfaces of a pack frame included in a battery pack according to an embodiment of the present invention.

2 to 5, the battery pack 100 according to an embodiment of the present invention accommodates a battery cell stack 110 including a plurality of battery cells 111 and a battery cell stack 110. It includes a pack frame 120, a venting flow path 130 formed between the battery cell stack 110 and the pack frame 120, and a mesh member 140 located on one side of the pack frame 120. can do.

Here, the battery pack 100 shown in FIGS. 2 and 3 may be provided with a front cover covering the front of the pack frame 120, and the front of the pack frame 120 shown in FIG. 5 is the battery pack 100 ), the front cover may be removed. The front cover may be disposed to cover the front surface of the pack frame 120 shown in FIG. 5 (a) to protect the front surface of the pack frame 120 where a member such as a BMS and terminals of battery cells are located. The front cover may be made of an insulating material, through which an electrical connection between the pack frame 120 and the outside may be blocked.

The battery cell stack 110 may include a plurality of battery cells 111 . The battery cells 111 may be stacked in one direction to form the battery cell stack 110 . Here, the stacking direction of the battery cells 111 may be a direction from the front to the back or from the back to the front of the pack frame 120 . At this time, the front and rear surfaces of the pack frame 120 may be two faces facing each other in the longitudinal direction of the pack frame 120 . The front and rear surfaces of the pack frame 120 may be two faces facing each other on the y-axis.

The type of battery cell 111 included in the battery pack 100 is not particularly limited, and a pouch-shaped, prismatic, or jelly roll-shaped cylindrical battery cell may all be applied. However, in order to accommodate a large number of battery cells 111 in a limited space inside the battery pack 100, it may be preferable to use pouch-type or prismatic batteries.

The pack frame 120 may be for protecting the battery cell stack 110 and electrical components connected thereto from external physical impact. The structure of the pack frame 120 may vary. For example, the pack frame 120 may be in the form of a mono frame covering the top, side and bottom surfaces of the battery cell stack 110 . As another example, the pack frame 120 may include an upper frame covering upper and side surfaces of the battery cell stack 110 and a lower frame covering the lower surface of the battery cell stack 110 . In another example, the pack frame 120 may include a lower frame covering the side and lower surfaces of the battery cell stack 110 and an upper frame covering the upper surface of the battery cell stack 110 . The structure of the pack frame 120 is not limited by the above-described example, and may be provided in a different form.

The pack frame 120 may include a portion having high thermal conductivity in order to rapidly dissipate heat generated in the internal space to the outside. For example, at least a portion of the pack frame 120 may be made of a metal having high thermal conductivity, and examples thereof may include aluminum, gold, silver, copper, platinum, or an alloy including the same. Since the heat dissipation effect by the pack frame 120 improves as the thermal conductivity of the metal increases, there is no particular range for the thermal conductivity value. In addition, the pack frame 120 may partially have electrical insulation, and an insulation film may be provided or an insulation coating may be applied to a location where insulation is required. A portion of the pack frame 120 to which an insulating film or an insulating coating is applied may be referred to as an insulating portion.

The venting passage 130 may be for discharging gas generated from the battery cell stack 110 to the outside of the pack frame 120 . The venting passage 130 may refer to a separation space between the battery cell stack 110 and the pack frame 120 . Flame, gas, etc. discharged from the battery cell 111 to the venting passage 130 may move along the venting passage 130 and be discharged to the outside through the mesh member 140 provided in the pack frame 120 .

The venting passage 130 may be formed between the front and rear surfaces of the pack frame 120 and the battery cell stack 110 . The venting passage 130 may be formed between the side of the pack frame 120 and the battery cell stack 110 . When an ignition phenomenon occurs in the battery cell 111, the gas discharged from the battery cell 111 is discharged to the venting passage 130 located on the side of the pack frame 120, and along the venting passage 130, the pack frame ( 120) can be moved toward the front or back.

As shown in FIG. 4 , when the battery cells 111 are stacked in the longitudinal direction of the pack frame 120, that is, along the side surface, the electrode leads of the battery cells 111 may be disposed toward the side surface of the pack frame 120. . The venting passages 130 formed on the side surfaces of the pack frame 120 correspond to the battery cells 111, so that gas discharged from the battery cells 111 can be effectively collected and moved. Here, the electrode lead may be a conductive member protruding out of the cell case of the battery cell 111 in order to form an electrical connection between the battery cell 111 and another member. When the battery cell 111 heats up, the electrode lead providing the electron movement path may have a higher temperature than other parts of the battery cell 111 . Since the venting passage 130 is positioned close to the electrode lead, heat dissipation from the electrode lead or movement of discharged gas around the electrode lead may be promoted.

4, when the battery cells 111 are stacked along the longitudinal direction of the pack frame 120, that is, along the side, the outermost battery cell of the battery cell stack 110 is the front or rear surface of the pack frame 120. can be arranged to match. In the battery cell stack 110, the outermost battery cell may be located close to the outside and may have a relatively low temperature compared to other battery cells 111. As such, the venting passage 130 moves the gas discharged from the ignition cell 111A in the direction where the outermost battery cell having a relatively low temperature is located, thereby minimizing the temperature gradient inside the battery pack 100 and providing more stable gas. release can be made possible.

The mesh member 140 may be for discharging gas, sparks, or flame inside the pack frame 120 when the battery cell 111 is ignited. The mesh member 140 may be for minimizing the discharge of sparks. The mesh member 140 may include a plurality of small-sized openings, through which the discharge of sparks or particles may be suppressed without interfering with gas discharge. In addition, sparks moved together during gas discharge may collide with the mesh member 140, and energy of the spark may be lost through this, and thus the spark may be changed into particles. As such, if the emission of sparks is limited by the mesh member 140 or the energy loss of the high-temperature particles increases, the amount of sparks emitted to the outside decreases, thereby reducing the possibility of the sparks coming into contact with external oxygen, and an additional ignition phenomenon. this can be prevented.

The mesh member 140 may be located on one side of the pack frame 120 . One surface of the pack frame 120 on which the mesh member 140 is formed may be the front or rear surface of the pack frame 120 . The mesh member 140 includes a first mesh member 142 formed on the front surface of the pack frame 120 as shown in FIG. 5 (a) and a rear surface of the pack frame 120 as shown in FIG. 5 (b). It may include a second mesh member 144 formed on.

Referring to FIGS. 3 and 4 , the first mesh member 142 and the second mesh member 144 may be centrally located on the front or rear side of the pack frame 120 . Since the mesh member 140 is positioned at the center of the front or rear surface of the pack frame 120, a gas discharge path of the battery pack 100 may increase, and energy loss of spark may increase. Specifically, the gas generated in the battery cell 111 where the ignition phenomenon occurs, that is, the ignition cell 111A, moves along the venting passage 130 and is discharged to the first mesh member 142 and the second mesh member 144. It can be. In the conventional battery pack 10 shown in FIG. 1, gas generated from the battery cells is discharged to the front and rear sides of the battery pack 10 along a straight path, but in the battery pack 100 of this embodiment, the battery pack 10 ) Since the gas moving toward the front and rear surfaces is not immediately discharged and the movement direction is switched to pass through the mesh member 140, the movement path of the gas may increase.

6 is examples of mesh members included in a battery pack according to an embodiment of the present invention. 7 illustrates an example in which a mesh member included in a battery pack according to an embodiment of the present invention is provided as two mesh sheets.

Referring to FIGS. 6 and 7 , the mesh member 140 of this embodiment may be provided in various patterns. The mesh member 140 may be provided in various line patterns. For example, the mesh member 140 may be provided in a lattice pattern, and the lattice pattern may be formed through a plurality of orthogonal straight lines as shown in FIG. 6 (a), or orthogonal as shown in FIG. It may be formed through a plurality of oblique lines. In addition, the mesh member 140 may be provided in an oblique pattern as shown in FIG. 6 (c), a wavy pattern as in FIG. 6 (d), and a straight line pattern as in FIGS. 6 (e) and 6 (f). It may be provided to have various patterns not shown in 6.

The mesh member 140 may be formed by overlapping at least two meshes. If the mesh member 140 is provided as two or more meshes rather than as one mesh, collision between the mesh member 140 and sparks increases, so the amount of sparks emitted to the outside can be minimized. In addition, in forming the mesh member 140 using at least two meshes as shown in FIG. 7, if the openings of the respective meshes do not completely correspond to each other, that is, are arranged so as to partially overlap, sparks or gases pass through. The opening size of the mesh may be reduced. Accordingly, by using at least two meshes, manufacturing and design of the mesh member 140 are simplified and diversified.

8 is a view showing an example in which a venting guide tube is provided in a battery pack according to an embodiment of the present invention. 9 is a perspective view of a venting guide tube included in the battery pack of FIG. 8 . 10 is a cross-sectional view taken along the A-A axis of FIG. 9 .

Referring to FIGS. 8 to 10 , a venting guide pipe 150 may be provided in the battery pack 100 of this embodiment.

The venting guide pipe 150 may be located in the venting passage 130 . When the venting passage 130 and the battery cell stack 110 are not isolated, the gas discharged from the battery cell 111 where the ignition phenomenon occurs moves along the venting passage 130, and the adjacent battery cell 111 ) can affect However, when the venting guide pipe 150 is disposed in the venting passage 130, the gas moving through the venting passage 130 is isolated from other battery cells 111, so that high-temperature gas or the like is transmitted to the adjacent battery cells 111. impact can be minimized. As such, the venting guide pipe 150 allows gas discharged from the battery cells 111 to move through the inside of the venting guide pipe 150, thereby limiting the movement path of the gas.

The venting guide pipe 150 may have a tube shape extending in one direction. The venting guide pipe 150 may be arranged such that its longitudinal direction corresponds to the stacking direction of the battery cells 111 . The venting guide pipe 150 may have a tube shape extending in the stacking direction of the battery cells 111 . This may be to maximize the number of battery cells 111 corresponding to the venting guide tube 150.

The venting guide pipe 150 may correspond to the battery cell 111 . The battery cell 111 may include an electrode lead 112 protruding to one side of the cell case, and the venting guide pipe 150 may correspond to the electrode lead 112 of the battery cell 111 . The venting guide pipe 150 may include a hole 152 corresponding to the electrode lead 112 of the battery cell 111 . The electrode lead 111 may be located close to the hole 152 provided in the venting guide pipe 150 or may be inserted into the hole 152, through which the gas discharged from each battery cell 111 is discharged through the venting guide pipe. (150) can be easily collected.

The venting guide tube 150 may be disposed between the battery cell stack 110 and the pack frame 120, and may be positioned to correspond to the side surface of the pack frame 120. One venting guide pipe 150 may be provided or two may be provided to correspond to both sides of the pack frame 120 . When there are two venting guide tubes 150 and the battery cell 111 includes two electrode leads 112 protruding on both sides, the venting guide tube 150 is the electrode lead 112 of each battery cell 111. ) and may correspond to each other.

On the other hand, 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. can be included with

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

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 of those skilled in the art using the basic concept of the present invention defined in the following claims are also present. belong to the scope of the invention.

100: battery pack
110: battery cell stack
111: battery cell
120: pack frame
130: venting euro
140: mesh member
150: venting guide pipe

Claims (9)

A battery cell stack including a plurality of battery cells and
Including a pack frame accommodating the battery cell stack,
A venting passage for discharging gas generated from the battery cell is provided between the battery cell stack and the pack frame,
Mesh members are formed on the front and rear surfaces of the pack frame,
When the inside of the battery pack is ignited, the gas caused by the ignition is discharged by moving through the venting passage and passing through the mesh member. In paragraph 1,
The battery pack wherein the mesh member is located at the center of the front and rear surfaces of the pack frame. In paragraph 1,
The battery pack wherein the mesh member includes two meshes overlapping each other. In paragraph 1,
The battery cell stack includes a plurality of battery cells stacked in a direction from the front side of the pack frame to the rear side. In paragraph 1,
A battery pack in which a venting guide pipe is located in the venting passage. In paragraph 5,
The battery pack according to claim 1 , wherein the venting guide pipe corresponds to a side surface of the battery pack. In paragraph 5,
The venting guide tube is a battery pack having a tube shape extending along the stacking direction of the battery cell. In paragraph 5,
The battery pack of claim 1, wherein the venting guide tube includes a plurality of holes connected to electrode leads of the battery cell. A device comprising at least one battery pack according to claim 1 .

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