KR20240030986A - Battery pack and vehicle including same - Google Patents

Abstract

A battery pack and a vehicle including the same are disclosed.
A battery pack according to an embodiment of the present invention includes a cell unit including at least one battery cell; and a receiving room having a bottom portion in which the cell unit is seated, and a case for accommodating the cell unit in the receiving room, wherein the bottom portion contains a mass that falls after being discharged from a battery cell included in the cell unit. It includes a pocket configured to collect.

Description

Battery pack and vehicle including same}

The present invention relates to a battery assembly, a battery pack including the same, and a vehicle. More specifically, it relates to a battery pack manufactured using a cell-to-pack method and a vehicle including the same.

Generally, secondary batteries refer to batteries that can be repeatedly charged and discharged, such as lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. The output voltage of the battery cell, which is the basic unit of charging and discharging of these secondary batteries, is approximately 2.5V to 4.2V.

Recently, secondary batteries have been applied to devices that require high output voltage and large charging capacity, such as electric vehicles or ESS (Energy Storage Systems), and multiple battery cells are connected in series or parallel to form battery modules. Battery packs, which are manufactured by forming a battery module and connecting a plurality of battery modules thus configured in series or parallel, are widely used.

However, as disclosed in Korean Patent Publication No. 10-2379227, Korean Patent Publication No. 10-2022-0052183, etc., the existing technology constructs a battery module by housing battery cells in a box-shaped metal case, and these batteries Since the battery pack is manufactured by housing the modules back in the battery pack case, there is a problem that the weight and volume of the entire battery pack increases and the energy density of the battery pack decreases.

In addition, in order to increase the energy density of the battery pack, when the existing Cell To Pack method of installing multiple battery cells directly into the pack case of the battery pack is applied to a pouch-type secondary battery with a soft case, many It is difficult to handle or stack battery cells at the same time, and there is a risk of damage to the battery cells in the process of mounting them in the pack case.

In addition, in the existing technology, when thermal runaway of a battery cell occurs, particles or foreign substances emitted from the battery cell accumulate inside the battery pack, making it difficult to discharge gases smoothly, and the internal pressure of the battery pack increases, causing damage to the battery pack. However, there is a problem that may cause an explosion.

The technical problem to be solved by the present invention is a battery pack that can safely and easily handle and install battery cells during battery pack manufacturing while reducing the overall weight and volume of the battery pack and increasing energy density, and including the same. It is to provide a vehicle that does this.

In addition, another technical problem to be solved by the present invention is to provide a battery pack that prevents structural damage or explosion of the battery pack when thermal runaway of battery cells occurs and suppresses chain thermal runaway between battery cells, and a vehicle including the same. It is done.

A battery pack according to an aspect of the present invention includes a cell unit including at least one battery cell; and a receiving room having a bottom portion in which the cell unit is seated, and a case for accommodating the cell unit in the receiving room, wherein the bottom portion contains a mass that falls after being discharged from a battery cell included in the cell unit. It includes a pocket configured to collect.

In one embodiment, the cell unit includes a slot into which the at least one battery cell is inserted, an opening through which an electrode lead of the at least one battery cell inserted into the slot is exposed, and at least one battery cell inserted into the slot. It may further include a cell cover that covers the battery cells.

In one embodiment, the cell cover may be arranged so that the entrance of the slot faces the bottom part, and the entrance of the pocket may be provided at a position corresponding to the entrance of the slot.

In one embodiment, the entrance of the pocket may be provided at a position corresponding to an entrance portion of the slot adjacent to an electrode lead of the at least one battery cell.

In one embodiment, the cell unit includes a bus bar electrically connected to the electrode lead; And it may further include a bus bar frame disposed in the opening of the cell cover to support the bus bar.

In one embodiment, the bottom portion may further include a gas passage extending along the inside of the bottom portion, and the pocket may be configured to be connected to the gas passage.

In one embodiment, the bottom portion further includes a blocking film that blocks the entrance of the gas passage connected to the pocket, and the blocking film ruptures when the surrounding pressure rises above a predetermined pressure to close the entrance to the gas passage. It can be configured to be open.

In one embodiment, it further includes a heat sink disposed between the cell unit and the bottom portion to cool the battery cells included in the cell unit, wherein the heat sink corresponds to an entrance of the pocket. A guide hole may be provided in the portion to guide the mass to the entrance of the pocket.

In one embodiment, the guide hole may be configured to gradually widen from the pocket side to the cell unit side.

In one embodiment, a Thermal Interface Material (TIM) interposed between the cell unit and the heat sink may be further included.

In one embodiment, a plurality of cell units may be included, and the plurality of cell units may be stacked on one another in one direction.

In one embodiment, the at least one battery cell may be configured as a pouch-type secondary battery.

A vehicle according to another aspect of the present invention includes a battery pack according to any one of the above-described embodiments.

According to the present invention, a pocket configured to collect mass discharged from a battery cell and falling under its own weight is provided on the bottom of the battery pack case, thereby smoothing gas discharge in the event of thermal runaway of the battery cell and internal pressure of the battery pack. This can prevent damage or explosion of the battery pack due to elevation.

In addition, rather than housing multiple battery cells in a separate module case and mounting them on the battery pack case, they are only partially covered by a cell cover of a simplified structure and mounted directly on the battery pack case, thereby reducing the weight of the entire battery pack and reducing the weight of the entire battery pack. While reducing the volume and increasing the energy density of the battery pack, it can facilitate safe handling and installation of battery cells when manufacturing the battery pack, and reduce manufacturing costs.

Additionally, a gas passage connected to the pocket is provided on the bottom of the battery pack case, thereby diversifying gas venting paths inside the battery pack and providing an alternative path when other gas venting paths are blocked.

In addition, the gas moved through the gas passage provided on the bottom of the battery pack case or another gas passage provided on the wall of the case is discharged in a preset direction through the gas valve, thereby causing the gas of the battery pack mounted on the bottom of the vehicle to be discharged. The venting direction can be set to the rear or side rather than upward where the occupants are located, thereby improving the safety of the occupants.

In addition, the blocking portion of the cell cover supports the battery cell inserted into the slot of the cell cover and blocks removal of the battery cell, thereby preventing the battery cell from changing position or leaving the cell cover and ensuring the safety of the battery pack. and reliability can be guaranteed.

In addition, an insertion groove is provided in the blocking portion of the cell cover so that a jig that changes the slot width of the cell cover by contacting the inner surface of the cell cover can be easily inserted, thereby inserting a battery cell into the cell cover. This facilitates and prevents damage to the battery cells.

Furthermore, those skilled in the art to which the present invention pertains will be able to clearly understand from the following description that various embodiments according to the present invention can solve various technical problems not mentioned above.

1 is a diagram showing a battery pack according to an embodiment of the present invention.
Figure 2 is an exploded view showing the battery assembly of a battery pack according to an embodiment of the present invention.
Figure 3 is an enlarged view showing area M1 in Figure 1.
Figure 4 is a diagram showing a cell unit of a battery pack according to an embodiment of the present invention.
FIG. 5 is an exploded view showing the cell unit shown in FIG. 4.
FIG. 6 is a cross-sectional view taken along line A1-A1' of the battery pack shown in FIG. 1.
FIG. 7 is a diagram showing the lower part of the cell unit shown in FIG. 6.
Figures 8 and 9 are diagrams showing the assembly method of the cell unit shown in Figure 4.
Figure 10 is a diagram showing a cell cover according to a modified embodiment.
Figure 11 is a diagram showing a cell cover according to another modified embodiment.
Figure 12 is a diagram showing a vehicle according to an embodiment of the present invention.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings to clarify solutions corresponding to the technical problems of the present invention. However, when explaining the present invention, if the description of related known technology rather obscures the gist of the present invention, the description may be omitted. Additionally, the terms used in this specification are terms defined in consideration of the functions in the present invention, and may vary depending on the intention or custom of the designer, manufacturer, etc. Therefore, definitions of terms described below should be made based on the content throughout this specification.

For reference, in this specification, terms indicating direction are terms based on the components shown in the attached drawings, and are relative terms that can change depending on the posture or position of the actual components.

Figure 1 shows a battery pack 10 according to an embodiment of the present invention.

As shown in FIG. 1, the battery pack 10 includes a battery assembly 100 and a case 300 that accommodates one or two or more battery assemblies 100.

Additionally, the battery assembly 100 includes a plurality of cell units 200. Each cell unit 200 includes at least one battery cell and a cell cover that partially surrounds and covers the at least one battery cell, and is stacked with other cell units in the width direction (Y-axis direction). You can.

The battery cell included in each cell unit 200 may be composed of a pouch-type secondary battery. In this case, the pouch-type secondary battery can be manufactured by storing the electrode assembly and electrolyte material in a pouch-type case and sealing the case. Depending on the embodiment, the battery cell may be configured in various forms, such as a prismatic secondary battery or a cylindrical secondary battery.

These plurality of cell units 200 may be stacked in one direction and accommodated in the case 300 .

The case 300 has one or two or more receiving rooms (R1) having a bottom portion 310 in which the cell unit 200 is seated, and the cell unit 200 is accommodated in the receiving room (R1). do. For example, the case 300 may be configured to accommodate a plurality of battery assemblies 100 in separate accommodation rooms.

To this end, the case 300 may include a lower case 302 having an opening at the top and an internal space connected to the opening, and an upper case 304 covering the opening of the lower case 302. You can.

The lower case 302 may include a wall 312 that divides its internal space into a plurality of accommodation rooms. A gas inlet 314 through which gas generated from the battery assembly 100 accommodated in the corresponding receiving room (R1) flows may be provided in the wall 312 of the lower case 302 adjacent to each receiving room (R1). . Additionally, a gas valve 316 that discharges gas may be provided on the outer surface of the lower case 302. A gas passage connecting the gas inlet 314 and the gas valve 316 may be provided inside the lower case 302.

In this case, the gas venting path for discharging gas to the gas valve 316 may be provided individually for each accommodation room. That is, the gas generated in the first receiving room is discharged through the first gas venting path leading to the first gas inlet, the first gas passage, and the first gas valve, and the gas generated in the second receiving room is discharged through the second gas inlet and the first gas valve. It may be configured to be discharged through a second gas venting path leading to two gas channels and a second gas valve.

As will be described again below, the bottom portion 310 of the receiving room R1 includes a pocket 310a configured to collect falling masses discharged from battery cells included in the cell unit 200. can do.

In addition, the battery pack 10 is disposed between the cell unit 200 of the battery assembly 100 and the bottom portion 310 of the receiving room R1 to cool the battery cells included in the cell unit 200. It may further include a heat sink 320.

In this case, the heat sink 320 may be provided at a portion of the heat sink corresponding to the entrance of the pocket 310a and may be provided with a guide hole 322 that guides the mass to the entrance of the pocket 310a. This heat sink 320 may be made of a metal material with high thermal conductivity and heat resistance.

Depending on the embodiment, the heat sink 320 may be formed integrally with the bottom portion 310 of the receiving room R1.

Meanwhile, the case 300 may be provided with an accommodation space R2 to accommodate various electrical components required for the operation of the battery pack 10.

In one embodiment, the battery pack 10 may further include a control module 330. This control module 330 includes a battery management system (BMS) that manages the charging and discharging operations, state of charge (SOC), and state of health (SOH) of the battery cells included in the battery assembly, and is installed in the case (300). ) can be installed in the receiving space (R2).

Additionally, the battery pack 10 may further include a switching unit 340. This switching unit 340 may be configured to control electrical connection between the battery pack 10 and an external circuit. To this end, the switching unit 340 may optionally include a current sensor, power relay, fuse, etc.

FIG. 2 shows an exploded view of the battery assembly 100 of the battery pack shown in FIG. 1 .

As shown in FIG. 2, the battery assembly 100 according to an embodiment of the present invention includes a plurality of cell units 200 and a support structure 110.

The plurality of cell units 200 each include at least one battery cell and are configured to be stacked side by side in the width direction (Y-axis direction). As will be described again below, each cell unit 200 may include at least one battery cell that is a basic unit of charge and discharge, and a cell cover that partially covers and supports the battery cell.

The support structure 110 is configured to support the plurality of cell units 200 and maintain the stacked state of the plurality of cell units 200. To this end, the support structure 110 may include a side wall 112 and an integrated end cover 114. The side wall 112 and the integrated end cover 114 may be arranged along the lateral circumference of the plurality of cell units 200 stacked on each other.

In one embodiment, the support structure 110 may include a pair of side walls 112 and an integrated end cover 114, respectively.

In this case, the side walls 112 are disposed one at each end of the plurality of cell units 200 based on the width direction (Y-axis direction) or the stacking direction of the plurality of cell units 200, It may be configured to support the cell unit 200.

That is, among a pair of side walls, the first side wall is disposed adjacent to the first cell unit located on the outermost side of the plurality of cell units 200, and the second side wall is disposed adjacent to the first cell unit located on the outermost side of the plurality of cell units 200. ) can be placed adjacent to the second cell unit located on the outermost side of the other side.

The side wall 112, together with the integrated end cover 114, which will be described later, brings the plurality of cell units 200 into close contact with each other to form a single cell unit block that can be handled simultaneously. In this case, the side wall 112 can evenly distribute the pressure applied to the plurality of cell units 200 throughout the cell units 200.

This side wall 112 may be made of a metal material including aluminum or stainless steel, or may be made of a material that combines metal and polymer synthetic resin through insert molding.

The integrated end covers 114 may be disposed one at each end of the plurality of cell units 200 based on the longitudinal direction (X-axis direction) of the plurality of cell units 200. In addition, the integrated end cover 114 has one end connected to the first side wall and the other end connected to the second side wall, and is one of the cell covers of the plurality of cell units 200. It may be configured to cover the openings of two or more cell covers together.

To this end, the side wall 112 may include connection portions 112a provided at both ends thereof and connected to one end or the other end of the integrated end cover 114. Correspondingly, the integrated end cover 114 has a main body portion that covers the openings of the plurality of cell units 200, and a corresponding body portion extending from this body portion and connected to the connection portion 112a of the side wall 112. It may include a connection portion 114a.

In one embodiment, the integrated end cover 114 has vent holes 114b for discharging gas generated from the battery cells of the cell unit in each part of the integrated end cover corresponding to the openings of the plurality of cell units 200. ) can be provided.

In addition, as shown in FIG. 2, the integrated end cover 114 extends from the main body to the lower end of the plurality of cell units 200, and includes a support portion 114c that supports the lower end of the plurality of cell units 200. ) may include.

This integrated end cover 114 may be made of a metal material including aluminum or stainless steel or a polymer synthetic resin, or may be made of a material combining metal and polymer synthetic resin through insert molding.

In this way, the integrated end cover 114, which supports the cell units and integrally covers the openings of the cell units, is applied to the battery assembly 100, so that unit end covers applied to each cell unit can be omitted, and the unit end covers 114 applied to each cell unit can be omitted. The manufacturing process can be simplified.

In Figure 3, the M1 area of Figure 1 is shown in an enlarged view.

As shown in FIG. 3, the side wall 112 and the integrated end cover 114 included in the support structure 110 of the battery assembly 100 are interconnected to support a plurality of cell units 200. there is. To this end, the connection portion 112a of the side wall 112 may be provided with an insertion groove into which the corresponding connection portion 114a of the integrated end cover 114 is inserted.

The corresponding connection part 114a of the integrated end cover 114 is inserted into the insertion groove provided in the connection part 112a of the side wall 112 and then connected to the side wall by a fastening member S1 such as a screw or bolt. It may be fixed to the connection portion 112a of (112).

In addition, the support portion 114c of the integrated end cover 114 extends from the main body of the integrated end cover 114 to the lower end of the plurality of cell units 200, and supports the lower end of the plurality of cell units 200. It can be configured to do so. In this case, the support portion 114c of the integrated end cover 114 may be configured to support the bus bar frame of each cell unit 200.

Figure 4 shows a cell unit 200 of a battery assembly according to an embodiment of the present invention.

As shown in FIG. 4, the cell unit 200 may include a cell cover 210 that partially covers and supports at least one battery cell and maintains it in an upright state.

Additionally, the cell unit 200 may further include a bus bar assembly 220. The bus bar assembly 220 includes a bus bar that is electrically connected to the electrode lead of the battery cell inserted into the cell cover 210, and can be placed at both ends of the cell cover 210 in the longitudinal direction (X-axis direction). there is.

In FIG. 5, the cell unit 200 shown in FIG. 4 is shown in an exploded view.

As shown in FIG. 5, the cell unit 200 may include at least one battery cell 202 and a cell cover 210.

The battery cell 202 corresponds to the most basic secondary battery that can be charged and discharged, and can be manufactured by storing an electrode assembly and electrolyte material inside a case and sealing the case. The electrode assembly may be manufactured by interposing a separator between the anode electrode and the cathode electrode.

This battery cell 202 may be composed of a pouch-type secondary battery having a predetermined length and height. Additionally, electrode leads 202a electrically connected to the electrode assembly may be provided at both ends of the battery cell 202 in the longitudinal direction (X-axis direction).

The cell cover 210 may be configured to partially cover and support at least one battery cell 202 and maintain it in an upright state. For example, as shown in FIG. 5 , the cell cover 210 may be configured to partially cover and support the three battery cells 202 stacked on each other and maintain the corresponding battery cells in an upright state.

To this end, the cell cover 210 has a slot 214 into which at least one battery cell 202 is inserted, and an electrode lead 202a of at least one battery cell 202 inserted into the slot 214. It has an opening 216 exposed to the outside of the cell cover 210 and may be configured to cover at least one battery cell 202 inserted into the slot 214.

When the cell unit 200 is seated in the receiving room (R1) of the case 300 described above, the cell cover 210 is such that the entrance of the slot 214 is located at the bottom portion 310 of the receiving room (R1). ) can be placed facing. In this case, the entrance of the pocket 310a provided in the bottom portion 310 may be provided at a position corresponding to the entrance of the slot 214.

This cell cover 210 may be configured in an 'n' shape or a 'u' shape that surrounds three sides of the at least one battery cell.

For example, the cell cover 210 includes a first cover part 210a forming one sidewall of the slot 214 into which at least one battery cell is inserted, and a second cover part forming the other sidewall of the slot 214 ( 210b), and a third cover part 210c that connects the first cover part 210a and the second cover part 210b and forms a distal end of the slot 214.

That is, the first cover portion 210a may cover one side of the battery cells inserted into the slot 214. Additionally, the second cover portion 210b may cover the other side of the inserted battery cells. Additionally, the third cover portion 210c may cover the top of the inserted battery cells.

In this case, between the first cover part 210a and the second cover part 210b, the entrance of the slot 214 and the electrode lead of at least one battery cell 202 inserted into the slot 214 An opening 216 through which 202a is exposed may be provided.

The height (or depth of the slot 214) (L1) of the cell cover 210 may be configured to be higher than the height (L2) of the battery cell 202 in an upright state. As a result, the free space created inside the slot 112a into which the battery cell 200 is inserted can be used as a gas discharge passage.

In Figure 5, the number of battery cells 202 covered by one cell cover 210 is shown as three, but the number of battery cells covered by the cell cover 210 varies depending on the scale of the cell cover 210. The number can be changed in various ways.

In one embodiment, the cell unit 200 may further include a busbar assembly 220. The bus bar assembly 220 includes a bus bar 222 electrically connected to the electrode lead 202a of the battery cell 202 inserted into the cell cover 210, and an opening of the cell cover 210 ( 216) may include a bus bar frame 224 that supports the bus bar 222.

In addition, the bus bar assembly 220 is disposed between the bus bar frame 224 and the integrated end cover 114 of the above-described support structure 110, and provides insulation to prevent short circuit of the bus bar 222. It may further include a cover 226. This insulating cover 226 may be made of polymer synthetic resin with insulating properties.

In one embodiment, the cell cover 210 may further include a blocking portion 218 provided at the entrance of the slot 214 to block removal of the battery cell inserted into the slot 214. The blocking portion 218 protrudes from the ends of the first cover portion 210a and the second cover portion 210b toward the entrance of the slot 214, respectively, and is configured to support the lower ends of the battery cells inserted into the slot 214. It can be.

In addition, in one embodiment, the blocking portion 218 contacts the inner surface of the cell cover 210 to determine the width of the slot 214, that is, between the first cover portion 210a and the second cover portion 210b. It may be provided with an insertion groove (218a) into which the finger of the jig that changes the spacing is inserted.

This cell cover 210 may be formed as one piece. For example, the cell cover 210 may be manufactured integrally through a sheet metal processing process or an injection process.

In this way, the cell cover 210 of a simplified structure is made of a metal material with higher rigidity than the battery cell case, and can protect the battery cell covered by the cell cover from external shock or vibration. For example, the cell cover 210 may be made of a material containing stainless steel (SUS), which is easy to process and has high corrosion resistance.

Although not shown in FIGS. 4 and 5 , the cell unit 200 may further include a clamping member configured to clamp the cell cover 210 . In this case, the clamping member clamps the cell cover 210 into which at least one battery cell is inserted, causing the slot 214 of the cell cover 210 to open or the battery cell inserted into the slot 214 ( 202) may be configured to prevent the cell cover 210 from being separated. This clamping member may be made of tape or a band-shaped metal material.

FIG. 6 shows a cross-sectional view taken along line A1-A1' of the battery pack shown in FIG. 1.

As shown in FIG. 6, when the cell unit 200 is seated in the receiving room (R1) of the case 300 described above, the cell cover 210 of the cell unit 200 is in its slot 214. ) may be arranged so that the entrance faces the bottom portion 310 of the receiving room (R1).

Additionally, the entrance of the pocket 310a provided in the bottom portion 310 may be provided at a position corresponding to the entrance of the slot 214. In this case, the entrance of the pocket 310a is the entrance part of the slot 214 of the cell cover 210 adjacent to the electrode lead 202a of the battery cell 202 inserted into the slot 214. It can be provided in a corresponding location. The reason is that when thermal runaway of the battery cell 202 occurs, gas venting frequently occurs at the edge of the battery cell 202 where the electrode lead 202a is located.

Meanwhile, the heat sink 320 disposed between the cell unit 200 and the bottom portion 310 is provided at a portion of the heat sink corresponding to the entrance of the pocket 310a of the bottom portion 310 to maintain the battery cell 202. A guide hole 322 may be provided to guide the mass discharged from the pocket 310a to the entrance of the pocket 310a. To this end, the guide hole 322 may be configured to gradually widen from the pocket 310a side to the cell unit 200 side.

In one embodiment, the battery pack 10 may further include a Thermal Interface Material (TIM) 350 interposed between the cell unit 200 and the heat sink 320. By increasing the heat transfer rate between the cell unit 200 and the heat sink 320 through the TIM 350, the cooling performance of the heat sink 320 can be further improved.

In one embodiment, the bottom portion 310 of the case 300 may include a gas passage 310b extending along the inside of the bottom portion 310. One end of this gas passage 310b may be connected to the pocket 310a, and the other end may be connected to the gas valve 316 of the case 300 described above.

In one embodiment, the bottom portion 310 may further include a blocking film 310c that blocks the entrance of the gas passage 310b connected to the pocket 310a. In this case, the blocking film 310c may be configured to rupture when the surrounding pressure rises above a predetermined pressure to open the entrance to the gas passage 310b. To this end, notches or grooves of various shapes may be formed in the blocking film 310c.

FIG. 7 shows the lower portion of the cell unit 200 shown in FIG. 6.

As shown in FIG. 7, the body of the battery cell 202 inserted into the cell cover 210 of the cell unit 200 and the bus bar frame 224 coupled to the end of the cell cover 210 are fixed. By being positioned at intervals, a venting area (VA) through which gas of the battery cell 202 is discharged may be provided at the bottom of the cell unit 200. The entrance to the pocket 310a described above may be provided at a location corresponding to the venting area VA.

Figures 8 and 9 show an assembly method of the cell unit 200 shown in Figure 4.

First, as shown in Figure 8, when the finger of the jig is inserted into the inside of the cell cover 210 and expanded between the first cover part 210a and the second cover part 210b of the cell cover 210, , the battery cell 202 can be safely inserted between the first cover part 210a and the second cover part 210b.

The blocking portion 218 of the cell cover 210 may have an appropriate length and shape so as not to damage the battery cells inserted as described above.

Next, as shown in FIG. 9, after at least one battery cell 202 is inserted into the cell cover 210 and the finger of the jig is removed, the first cover portion of the cell cover 210 (210a) and the second cover portion (210b) are returned to their original positions by their elastic force.

Then, the blocking portion 218 of the cell cover 210 supports the lower end of the battery cell 202 inserted between the first cover portion 210a and the second cover portion 210b to hold the battery cell 202. Removal can be blocked. To this end, the blocking portion 218 may be bent toward the inside of the cell cover 210 at the ends of each of the first and second cover portions 210a and 210b to form a locking structure.

Figure 10 shows a battery cell cover 210' according to a modified embodiment.

As shown in FIG. 10, the blocking portion 218' of the battery cell cover 210' is connected to the first cover portion 210a and the second cover portion 210b of the battery cell cover 210', respectively. It may be bent toward the inside of the battery cell cover 210' at the end, and may be bent toward the third cover portion 210c to form a locking structure.

Figure 11 shows a battery cell cover 210" according to another modified embodiment.

As shown in FIG. 11, the blocking portion 218" of the battery cell cover 210" is connected to each of the first cover portion 210a and the second cover portion 210b of the battery cell cover 210". After being bent from the end toward the third cover portion 210c, it may be bent round again toward the opposite side of the third cover portion 210c. In this way, the blocking portion 218" supports the battery cells with its round surface. By being configured to do so, damage to soft battery cells such as pouch-type battery cells can be prevented.

12 shows a vehicle 2 according to an embodiment of the present invention.

As shown in FIG. 12, the automobile 2 according to an embodiment of the present invention may include at least one battery pack 10 according to any one of the various embodiments described above.

In this way, the battery pack 10 provided in the vehicle 2 can provide electrical energy required for various operations of the vehicle 2.

For reference, the battery pack according to the present invention can be applied to various electric devices or electric systems in addition to vehicles, and can also be applied to ESS (Energy Storage System).

As described above, according to the present invention, a pocket configured to collect the mass discharged from the battery cell and falling under its own weight is provided on the bottom of the battery pack case, thereby facilitating gas discharge in the event of thermal runaway of the battery cell. , it can prevent damage or explosion of the battery pack due to an increase in the internal pressure of the battery pack.

In addition, rather than housing multiple battery cells in a separate module case and mounting them on the battery pack case, they are only partially covered by a cell cover of a simplified structure and mounted directly on the battery pack case, thereby reducing the weight of the entire battery pack and reducing the weight of the entire battery pack. While reducing the volume and increasing the energy density of the battery pack, it can facilitate safe handling and installation of battery cells when manufacturing the battery pack, and reduce manufacturing costs.

Additionally, a gas passage connected to the pocket is provided on the bottom of the battery pack case, thereby diversifying gas venting paths inside the battery pack and providing an alternative path when other gas venting paths are blocked.

In addition, the gas moved through the gas passage provided on the bottom of the battery pack case or another gas passage provided on the wall of the case is discharged in a preset direction through the gas valve, thereby causing the gas of the battery pack mounted on the bottom of the vehicle to be discharged. The venting direction can be set to the rear or side rather than upward where the occupants are located, thereby improving the safety of the occupants.

In addition, the blocking portion of the cell cover supports the battery cell inserted into the slot of the cell cover and blocks removal of the battery cell, thereby preventing the battery cell from changing position or leaving the cell cover and ensuring the safety of the battery pack. and reliability can be guaranteed.

In addition, an insertion groove is provided in the blocking portion of the cell cover so that a jig that changes the slot width of the cell cover by contacting the inner surface of the cell cover can be easily inserted, thereby inserting a battery cell into the cell cover. This facilitates and prevents damage to the battery cells.

Furthermore, it goes without saying that embodiments according to the present invention can solve various technical problems other than those mentioned in this specification in the relevant technical field as well as related technical fields.

So far, the present invention has been described with reference to specific embodiments. However, those skilled in the art will clearly understand that various modified embodiments can be implemented within the technical scope of the present invention. Therefore, the previously disclosed embodiments should be considered from an explanatory perspective rather than a limiting perspective. In other words, the scope of the true technical idea of the present invention is shown in the claims, and all differences within the scope of equivalents should be construed as being included in the present invention.

2: vehicle
10: Battery pack
100: Battery assembly
110: support structure
200: cell unit
202: battery cell
210, 210', 210": Cell cover
220: Busbar assembly
300: case
302: lower case
304: upper case
310: bottom part
310a: pocket
310b: gas passage
310c: barrier
320: heat sink
322: Guide hole
330: control module
340: switching unit

Claims (13)

A cell unit including at least one battery cell; and
It has a receiving room having a bottom portion in which the cell unit is seated, and includes a case for accommodating the cell unit in the receiving room,
The bottom portion includes a pocket configured to collect falling masses discharged from battery cells included in the cell unit. According to paragraph 1,
The cell unit has a slot into which the at least one battery cell is inserted, an opening through which an electrode lead of the at least one battery cell inserted into the slot is exposed, and covers the at least one battery cell inserted into the slot. A battery pack further comprising a cell cover. According to paragraph 2,
The cell cover is arranged so that the entrance of the slot faces the bottom portion,
A battery pack, characterized in that the entrance of the pocket is provided at a position corresponding to the entrance of the slot. According to paragraph 3,
The battery pack, wherein the entrance of the pocket is provided at a position corresponding to an entrance portion of the slot adjacent to an electrode lead of the at least one battery cell. According to paragraph 2,
The cell unit is,
a bus bar electrically connected to the electrode lead; and
The battery pack further includes a bus bar frame disposed in the opening of the cell cover to support the bus bar. According to paragraph 1,
The bottom portion further includes a gas passage extending along the inside of the bottom portion,
The battery pack, wherein the pocket is configured to be connected to the gas passage. According to clause 6,
The bottom portion further includes a blocking film that blocks the entrance of the gas passage connected to the pocket,
The battery pack is characterized in that the blocking film is configured to rupture when the surrounding pressure rises above a predetermined pressure to open the entrance to the gas passage. According to paragraph 1,
Further comprising a heat sink disposed between the cell unit and the bottom portion to cool the battery cells included in the cell unit,
The heat sink is a battery pack characterized in that it has a guide hole provided in a portion of the heat sink corresponding to the entrance of the pocket to guide the mass body to the entrance of the pocket. According to clause 8,
The guide hole is configured to gradually widen from the pocket side to the cell unit side. According to clause 8,
The battery pack further includes a Thermal Interface Material (TIM) interposed between the cell unit and the heat sink. According to paragraph 1,
Containing a plurality of the cell units,
A battery pack wherein a plurality of cell units are stacked on one another in one direction. According to paragraph 1,
A battery pack, wherein the at least one battery cell is composed of a pouch-type secondary battery. A vehicle comprising a battery pack according to any one of claims 1 to 12.

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