KR20230058850A - battery pack - Google Patents

Abstract

According to one embodiment, a battery pack comprises: a pack housing; and a plurality of cell assemblies accommodated within the pack housing. At least one of the plurality of cell assemblies includes a battery cell and a tab cover coupled to the battery cell. The pack housing may include an accommodation unit configured to accommodate at least a portion of the tab cover.

Description

battery pack {battery pack}

The present invention relates to a battery pack.

Secondary batteries, which are highly applicable to each product group and have electrical characteristics such as high energy density, are used not only for portable devices but also for electric vehicles (EVs), hybrid electric vehicles (HEVs) driven by electrical sources, or hybrid vehicles (HEVs). It is universally applied to golf carts and the like. These secondary batteries are attracting attention as a new energy source for improving energy efficiency and eco-friendliness in that they do not generate any by-products due to the use of energy as well as the primary advantage of significantly reducing the use of fossil fuels.

Lithium secondary batteries are classified into cylindrical batteries, prismatic batteries, and pouch-type batteries according to the shape of a case. A cylindrical battery and a prismatic battery are batteries having a structure in which an electrode assembly is mounted in a metal can, and a pouch-type battery is a battery having a structure in which an electrode assembly is mounted in a pouch-type case of an aluminum laminate sheet. Among them, a pouch type battery that can be stacked with a high degree of integration, has a high energy density per weight, is inexpensive, and is easily deformable has recently attracted a lot of attention.

Meanwhile, when configuring a battery pack by connecting a plurality of battery cells in series/parallel, a battery module composed of at least one battery cell is first configured, and other components are added using the at least one battery module to form a battery pack. How to configure is common.

A conventional battery module generally includes a plurality of battery cells electrically connected to each other and a module case accommodating the plurality of battery cells.

A battery pack must accommodate as many battery cells as possible within a limited space in order to have high energy density. However, when the battery cells are first accommodated in the module case and then accommodated in the pack case, it is difficult to provide a high level of energy density. Accordingly, a method of directly accommodating a battery cell in a pack case has recently emerged.

However, when the battery cells are directly disposed inside the pack case, there is a problem in that the alignment between the battery cells is misaligned. For example, when the battery cells are seated on the bottom of the case, if the heights of the battery cells are not uniform, the positions of the electrodes of the battery cells are not uniform, which can increase the defect rate when the bus bar and the battery cells are connected later. there is. Accordingly, there is a need for a method for easily or accurately aligning battery cells inside a pack.

An object of the present invention is to provide a structure for effectively aligning battery cells inside a battery pack. In addition, an object of the present invention is to improve the energy density of a battery pack by accommodating a relatively large number of battery cells inside the pack.

A battery pack according to an embodiment includes a pack housing; and a plurality of cell assemblies accommodated inside the pack housing, wherein at least one of the plurality of cell assemblies includes a battery cell and a tab cover coupled to the battery cell, and the pack housing covers the tab cover. It may include an accommodating portion configured to accommodate at least a part of it.

In one embodiment, the battery cell includes a cell body and an electrode tab drawn out from the cell body, and the tab cover may be coupled to the electrode tab.

In one embodiment, the electrode tab may be inserted into the tab cover, and the tab cover may be configured to expose a part of the tab cover to the outside of the tab cover.

In one embodiment, the electrode tab may include two or more electrode tabs drawn upward from the cell body.

In one embodiment, the tab cover may be coupled to an upper portion of the battery cell, the pack housing may include an upper plate disposed above the plurality of cell assemblies, and the accommodating portion may be provided on the upper plate.

In one embodiment, the battery pack may further include a bus bar disposed on the upper plate and electrically connected to the battery cell when the tab cover is accommodated in the accommodating part.

In one embodiment, a portion of the bus bar may be exposed to the accommodating portion.

In one embodiment, a part of the bus bar may be inserted into the frame.

In one embodiment, the bus bar may be configured to electrically connect two different cell assemblies.

In one embodiment, the bus bar may be configured to electrically connect a battery cell and an external device of the pack housing.

In one embodiment, one of the upper plate or the tab cover may include a fastening protrusion, and the other may include a fastening groove accommodating the fastening protrusion.

In one embodiment, the tab cover may include an internal bus bar connected to the electrode tab.

In one embodiment, the cell assembly may include two or more battery cells, and the tab cover may be coupled to the two or more battery cells.

In one embodiment, the battery pack may further include an elastic member disposed between the plurality of cell assemblies.

In one embodiment, the pack housing may include a lower plate disposed under the plurality of cell assemblies, and a heat dissipation member may be disposed between the battery cell and the lower plate.

A battery pack according to an embodiment includes a pack housing; a plurality of battery cells disposed inside the pack housing; and a tab cover coupled to an electrode tab of at least one battery cell among the plurality of battery cells, wherein the plate of the pack housing has an accommodating portion configured to accommodate the tab cover and disposed in the accommodating portion to form the tab cover. The cover may include a bus bar connected to the electrode tab when accommodated in the accommodating part.

In one embodiment, the electrode tab includes two or more electrode tabs drawn out in a first direction, the pack housing faces the plurality of battery cells in the first direction, and the plate on which the accommodating portion and the bus bar are provided. can include

According to the present invention, battery cells can be effectively aligned inside a battery pack. In addition, the battery pack can accommodate a relatively large number of battery cells, thereby providing high energy density.

1 is a perspective view of a battery pack according to an exemplary embodiment.
FIG. 2 is an exploded perspective view of the battery pack of FIG. 1 .
3 is a perspective view of the cell assembly according to the first embodiment.
4 is an exploded view of the cell assembly of FIG. 3 .
FIG. 5 is a IV-IV′ cross-sectional view of the cell assembly of FIG. 3 .
6 is a perspective view of a cell assembly according to a second embodiment.
7 is an exploded view of the cell assembly of FIG. 6 .
FIG. 8 is a V-V' cross-sectional view of the cell assembly of FIG. 6 .
9A is a II′ cross-sectional view of the battery pack of FIG. 1 in the first embodiment.
9B is a II′ cross-sectional view of the battery pack of FIG. 1 in the second embodiment.
10 is a II-II' cross-sectional view of the battery pack of FIG. 1 .
11A illustrates an elastic member disposed between battery cells according to an embodiment.
11B illustrates a metal plate disposed between battery cells in one embodiment.

The terms used in this document are general terms in consideration of functions in various embodiments of the present invention. However, these terms may vary depending on the intention of a technician working in the field, legal or technical interpretation, and the emergence of new technologies. Also, some terms may be terms arbitrarily selected by the applicant. These terms may be interpreted as defined in this document, and if there is no specific term definition, they may be interpreted based on the overall content of this document and common technical knowledge in the art.

In addition, the same reference numerals or numerals in each drawing attached to this document indicate parts or components that perform substantially the same function. For convenience of explanation and understanding, the same reference numerals or symbols will be used in different embodiments. That is, even if all components having the same reference numerals are shown in a plurality of drawings, the plurality of drawings do not mean one embodiment.

Also, in this document, terms including ordinal numbers such as “first” and “second” may be used to distinguish between components. These ordinal numbers are used to distinguish the same or similar components from each other, and the meaning of the term should not be limitedly interpreted due to the use of these ordinal numbers. For example, elements combined with such ordinal numbers should not be construed as limiting the use order or arrangement order by the number. If necessary, each ordinal number may be used interchangeably.

In this document, singular expressions include plural expressions unless the context clearly indicates otherwise. That is, even if a certain element is expressed in the singular in this document, it should not be interpreted as excluding the provision of a plurality of the corresponding element unless otherwise specified. For example, when it is assumed that a first member is disposed on a frame in an embodiment, unless otherwise specified, the embodiment is not limited to disposing only one first member on the frame, and two or more first members are disposed on the frame. It should be understood as including the arrangement of the first members in the frame.

In this document, the terms "comprise" or "comprise" are intended to indicate that there are features, numbers, steps, operations, components, parts, or combinations thereof described herein, but that one or more other It should be understood that the presence or addition of features, numbers, steps, operations, components, parts, or combinations thereof is not precluded.

In this document, the X direction, Y direction, and Z direction mean directions parallel to the X axis, directions parallel to the Y axis, and directions parallel to the Z axis shown in the drawings, respectively. In addition, unless otherwise specified, the X direction is a concept that includes both the +X-axis direction and the -X-axis direction, and this applies to the Y-direction and the Z-direction as well.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the spirit of the present invention is not limited to the presented examples. For example, a person skilled in the art who understands the spirit of the present invention may suggest other embodiments included in the scope of the spirit of the present invention through the addition, change, or deletion of elements, but this is also the scope of the present invention. It will be said that it is included within the scope of thought.

1 is a perspective view of a battery pack 1 according to an exemplary embodiment. FIG. 2 is an exploded perspective view of the battery pack 1 of FIG. 1 .

Referring to FIGS. 1 and 2 , the battery pack 1 includes a plurality of battery cells 110 and a pack housing 300 accommodating the plurality of battery cells 110 . Some of the battery cells 110 may be connected to a power relay assembly (PRA) outside the pack housing 300 through a bus bar. The power relay assembly 2 may supply or cut off power from the high voltage battery to the motor. The power relay assembly 2 is only an example, and the battery pack 1 can be connected to other devices as well.

In one embodiment, the battery cell 110 may be directly disposed inside the battery pack 1 . That is, all single-cell battery cells 110 are assembled and fixed inside the pack housing 300 to form the entire battery pack 1 . This can reduce the number of parts of the battery pack 1 and improve production efficiency. In addition, when the battery cell 110 is directly placed inside the battery pack 1 instead of being configured as a battery module and then placed inside the battery pack 1, the internal space of the battery pack 1 is reduced. It can be efficiently utilized, and the energy density of the battery pack 1 can be increased.

In one embodiment, the tab cover 120 is coupled to the battery cell 110, and in this document, a configuration in which the tab cover 120 is coupled to the battery cell 110 is referred to as the cell assembly 100. Details of the cell assembly 100 will be described with reference to FIGS. 3 to 8 .

The cell assemblies 100 are accommodated inside the pack housing 300 . The pack housing 300 includes a lower plate and an upper plate 320 spaced apart from and opposed to the lower plate 310 . The cell assemblies 100 are disposed in a space between the lower plate 310 and the upper plate 320 . A front plate 330 , a rear plate 340 , and an end plate 350 surround side surfaces of the cell assemblies 100 . For example, the end plate 350 is disposed on both sides of the cell assemblies 100 in the X direction, and the front plate 330 and the rear plate 340 are disposed on both sides in the Y direction.

The two end plates 351 and 352 disposed on both sides of the cell assembly 100 in the stacking direction (ie, the X direction) may apply force compressing the battery cells 110 in the stacking direction. This suppresses swelling of the battery cells 110 to some extent, thereby preventing or minimizing deformation of the pack housing 300 . In addition, the performance of the battery cell 110 can be improved by removing gas generated when the battery cell 110 is charged or discharged and distributing the electrolyte evenly on the electrode plate.

On the other hand, the configuration and shape of the pack housing 300 shown in FIGS. 1 and 2 are merely examples, and it is sufficient to be configured to house the cell assemblies 100 .

In one embodiment, the battery cell 110 is coupled to the pack housing 300 via the tab cover 120. In one embodiment, the pack housing 300 may include an accommodating portion 360 configured to accommodate at least a portion of the tab cover 120 . The battery cell 110 may be disposed at a specific location inside the pack housing 300 by a coupling between the tab cover 120 and the accommodating portion 360 .

In one embodiment, the accommodating portion 360 may be provided in a form corresponding to the tab cover 120 . For example, the accommodating part 360 is provided on the lower surface of the upper plate 320 (the surface facing the battery cells 110) and is recessed upward (ie, in the +Z direction) than other parts. can be provided.

As the tab cover 120 is accommodated in the accommodating portion 360 , the battery cell 110 may be disposed at a specific location inside the pack housing 300 . Referring to FIG. 2 , a plurality of accommodating parts 360 are arranged at regular intervals on the upper plate 320, and as the plurality of cell assemblies 100 are coupled to the plurality of accommodating parts 360, respectively, the battery cells (110) may be aligned at regular intervals.

The battery cell 110 is coupled to the pack housing 300 through the tab cover 120 instead of being directly coupled to the pack housing 300, and thus the battery cell 110 is more stably fixed inside the pack housing 300. It can be. In addition, the tab cover 120 can be relatively easily manufactured to have a uniform size or flatness, and thus the battery cells 110 can be relatively accurately and easily aligned inside the pack housing 300 . For example, the tab cover 120 may allow the battery cells 110 to be arranged at regular intervals from each other.

The battery cell 110 may be fixed on the lower plate 310 through a heat dissipation member (not shown). For example, a thermal resin may be applied between the battery cell 110 and the lower plate 310 and then cured to attach the battery cell 110 to the lower plate 310 . The lower plate 310 may function as a heat sink that absorbs and diffuses heat generated from the battery cell 110 or dissipates heat. Additionally, a flow path through which a coolant can flow is provided inside or on one side of the lower plate 310 , and heat of the battery cell 110 can be absorbed while the coolant passes through the inside or one side of the lower plate 310 .

The battery cell 110 may be connected in series or parallel with another battery cell 110 through a bus bar 370, or may be connected to a device outside the battery pack 1 (eg, the power relay assembly 2 of FIG. 1). can In one embodiment, the bus bar 370 is disposed on the upper plate 320, and when the tab cover 120 is inserted into the receiving portion 360 provided on the upper plate 320, the battery cell 110 is disposed on the bus bar 370. ) can be electrically connected to

Referring to FIG. 2 , the electrode tab 111 of the battery cell 110 is inserted into the tab cover 120, and a portion thereof is exposed to the outside of the tab cover 120. At least a portion of the bus bar 370 is exposed in the accommodating portion 360, and when the tab cover 120 is inserted into the accommodating portion 360, the electrode tab 111 exposed to the outside of the tab cover 120 is an upper plate. It may be electrically connected to the bus bar 370 disposed in the accommodating portion 360 of 320.

According to an embodiment, only by coupling the plurality of cell assemblies 100 to the top plate 320, the plurality of cell assemblies 100 interact with each other through the bus bar 370 provided on the top plate 320. can be electrically connected to Accordingly, the process of electrically connecting the cell assemblies 100 during the pack manufacturing process can be performed very easily and effectively.

Meanwhile, referring to FIGS. 1 and 2 , 12 cell assemblies 100 are disposed inside the pack housing 300 in one row, but this is only an example, and the embodiment of the present document is not limited thereto. For example, more or less than 12 cell assemblies 100 may be disposed inside the pack housing 300 in two or more rows.

3 is a perspective view of the cell assembly 100 according to the first embodiment. FIG. 4 is an exploded view of the cell assembly 100 of FIG. 3 . FIG. 5 is a IV-IV' cross-sectional view of the cell assembly 100 of FIG. 3 .

FIG. 3 shows an embodiment of the cell assembly 100 accommodated inside the battery pack 1 of FIG. 1 . 3 to 5 , the battery cell 110 includes an electrode tab 111 extending upward from the cell body 112, and the tab cover 120 is coupled to the upper side of the battery cell 110. . The cell body 112 may include an electrode assembly and a case (or exterior material) surrounding the electrode assembly. The electrode assembly includes electrode plates stacked with a separator interposed therebetween, and the electrode tab is electrically connected to the electrode plate.

In one embodiment, the electrode tab 111 may include two or more electrode tabs drawn out from the cell body 112 in the same direction. For example, both the first electrode tab 111 - 1 and the second electrode tab 111 - 2 extend from the upper side (ie, the side facing the Z direction) of the cell body 112 . The first electrode tab 111-2 and the second electrode tab 111-2 may have different polarities.

Referring to FIG. 1 together, the space surrounded by the front plate 330, the rear plate 340, and the end plate 350 is opened upward (ie, in the +Z direction), and the electrode tab of the battery cell 110 extends in the same direction as the direction in which the space is opened (ie, in the +Z direction). Accordingly, if the upper plate 320 is removed from the battery pack 1, the electrode tab 111 is located at a position that is relatively easily accessible from the outside, facilitating work related to the electrode tab 111.

In one embodiment, the tab cover 120 is coupled to the battery cell 110. In one embodiment, the tab cover 120 is coupled to the electrode tab 111 of the battery cell 110. For example, the tab cover 120 includes a tab accommodating portion 121 therein, and the electrode tab 111 is inserted into the tab accommodating portion 121 .

In one embodiment, the tab cover 120 may be configured to expose the electrode tab 111 to the outside of the tab cover 120 . In one embodiment, the tab cover 120 may include an opening 122 open in a direction in which the electrode tab 111 is drawn out (ie, the +Z direction). The electrode tab 111 is partially exposed outside the tab cover 120 through the opening 122 after being inserted into the tab cover 120 .

In one embodiment, the tab cover 120 may include an internal bus bar 123 connected to the electrode tab 111 . Referring to FIG. 5 , the electrode tab 111 bypasses the internal bus bar 123 and is exposed to the opening 122 . For example, the electrode tab 111 may partially cover the inner bus bar 123 while being bent in a D-shaped shape, and may be partially disposed on an upper surface of the inner bus bar 123 . The internal bus bar 123 may be disposed on one side of the electrode tab 111 to support the electrode tab 111 .

When the tab cover 120 is inserted into the accommodating part 360 of the upper plate 320, it should be connected to the bus bar 370 disposed in the accommodating part 360, but the electrode tab 111 is provided in a relatively thin plate form. Therefore, the connection between the electrode tab 111 and the bus bar 370 may not be made reliably. Since the internal bus bar 123 has relatively high rigidity and may have a relatively flat surface, the electrode tab 111 is supported by the electrode tab 111 when connected to the bus bar 370, thereby supporting the bus bar 370 and the electrode. Contact reliability between the tabs 111 may be increased.

Meanwhile, the internal bus bar 123 is not an essential component and may be omitted in other embodiments. In addition, in the illustrated embodiment, the electrode tab 111 is exposed through the opening 122, but the conductive member electrically connected to the electrode plates inside the battery cell 110 is exposed to the outside of the tab cover 120 and is exposed to the bus bar. 370 is sufficient, and the conductive member exposed to the outside of the tab cover 120 does not necessarily need to be the electrode tab 111. For example, the electrode tab 111 is connected to the lower portion of the inner bus bar 123, the inner bus bar 123 is exposed to the outside of the tab cover 120, and the bus bar 370 is disposed on the upper plate 320. ) can be connected to

6 is a perspective view of a cell assembly 100'' according to the second embodiment. FIG. 7 is an exploded view of the cell assembly 100 ″ of FIG. 6 . FIG. 8 is a V-V' cross-sectional view of the cell assembly 100' of FIG. 6 .

FIG. 6 shows an embodiment of a cell assembly 100 ′ accommodated inside the battery pack 1 of FIG. 1 . 6 to 8 , unlike the cell assembly 1001 of FIG. 3 , in one embodiment, the cell assembly 100 ′ may include two or more battery cells 110a and 110b. That is, two or more battery cells 110a and 110b may be coupled to one tab cover 120 .

7 and 8 , the tab cover 120 accommodates both the first electrode tab 111a of the first battery cell 110a and the first electrode tab 111b of the second battery cell 110b. can The tab cover 120 accommodates the first tab accommodating portion 121a accommodating the first electrode tab 111a of the first battery cell 110a and the second electrode tab 111b of the second battery cell 110b. It may include a second tap receiving portion (121b) to do. In this case, the first electrode tab 111a and the second electrode tab 111b may have the same polarity.

In one embodiment, the tab cover 120 may be configured to expose the electrode tabs 111a and 111b to the outside of the tab cover 120 . In one embodiment, the tab cover 120 may include an opening 122 open upward. The electrode tabs 111a and 111b are partially exposed outside the tab cover 120 through the opening 122 after being inserted into the tab cover 120 .

In one embodiment, the first battery cell 110a and the second battery cell 110b may be attached to each other through an adhesive member 113 .

In the illustrated embodiment, two battery cells 110a and 110b constitute one cell assembly 100', but this is merely an example, and in another embodiment, three or more battery cells constitute one cell assembly 100'. ) can be configured. For example, three or more battery cells may be connected to one tab cover 120 .

In one embodiment, the tab cover 120 may include an internal bus bar 123 connected to the electrode tab 111 . Referring to FIG. 8 , the electrode tab 111 bypasses the internal bus bar 123 and is exposed to the opening 122 . The internal bus bar 123 may be disposed on one side of the electrode tab 111 to support the electrode tab 111 .

When the tab cover 120 is inserted into the accommodating part 360 of the upper plate 320, it should be connected to the bus bar 370 disposed in the accommodating part 360, but the electrode tab 111 is provided in a relatively thin plate form. Therefore, the connection between the electrode tab 111 and the bus bar 370 may not be made reliably. Since the internal bus bar 123 has relatively high rigidity and may have a relatively flat surface, the electrode tab 111 is supported by the electrode tab 111 when connected to the bus bar 370, thereby supporting the bus bar 370 and the electrode. Contact reliability between the tabs 111 may be increased.

Meanwhile, the internal bus bar 123 is not an essential component and may be omitted in other embodiments. In addition, in the illustrated embodiment, the electrode tab 111 is exposed through the opening 122, but the conductive member electrically connected to the electrode plates inside the battery cell 110 is exposed to the outside of the tab cover 120 and is exposed to the bus bar. 370 is sufficient, and the conductive member exposed to the outside of the tab cover 120 does not necessarily need to be the electrode tab 111. For example, the electrode tab 111 is connected to the lower portion of the inner bus bar 123, the inner bus bar 123 is exposed to the outside of the tab cover 120, and the bus bar 370 is disposed on the upper plate 320. ) can be connected to

In the cell assembly 100 and related descriptions of this document, the cell assembly 100 may be replaced with the cell assembly 100' described in FIGS. 6 to 8 .

9A is a cross-sectional view of the battery pack 1 of FIG. 1 taken along line I-I' in the first embodiment. 9B is a cross-sectional view of the battery pack 1 of FIG. 1 taken along line I-I' in the second embodiment. 10 is a II-II' cross-sectional view of the battery pack of FIG. 1 .

In one embodiment, the pack housing 300 includes an accommodating portion 360 configured to accommodate at least a portion of each of the battery cells 110 . The accommodating part 360 may be provided on the upper plate 320 . Referring to FIGS. 9A to 10 , the accommodating portion 360 may be provided on the upper plate 320 and accommodate a portion of the tab cover 120 . In FIG. 9A, the Y-direction width of the accommodating portion 360 is greater than the Y-direction width of the tab cover 120, and thus there is a gap in the Y-direction between the accommodating portion 360 and the tab cover 120, but this is an example However, in another embodiment, the tab cover 120 may be tightly fitted to the accommodating portion 360 so that a gap in the Y direction may not exist between them.

In one embodiment, the accommodating portion 360 may be provided in a form corresponding to the tab cover 120 . Referring to FIG. 9A , the tab cover 120 has a rectangular bar shape extending in one direction, and the accommodating portion 360 is provided in the shape of a square groove extending in one direction to accommodate the tab cover 120 . In FIG. 9A , the accommodating portion 360 is configured to accommodate most of the tab cover 120, but this is merely an example, and the accommodating portion 360 may accommodate only a portion of the tab cover 120.

Referring to FIG. 9B , the tab cover 120 includes several protrusions, and the accommodating part 360 is configured to accommodate each protrusion. The tab cover 120 includes a first protrusion 124 and a second protrusion 125 accommodating the first electrode tab 111-1 and the second electrode tab 111-2, respectively, which are upper plates ( 320 may be accommodated in the first accommodating part 361 and the second accommodating part 362 respectively.

Referring to FIG. 9B , in one embodiment, the tab cover 120 includes a fastening protrusion 126 protruding toward the upper plate 320, and the upper plate 320 has a fastening groove accommodating the fastening protrusion 126. (380). In the illustrated embodiment, the fastening protrusion 126 may be configured not to fall out of the fastening groove 380 when inserted into the fastening groove 380 . For example, the fastening protrusion 126 may include a hook 126a at an end thereof, and the fastening groove 380 may include a hooking portion 380a corresponding to the hook 126a. When the fastening protrusion 126 is inserted into the fastening groove 380, the hook 126a is caught on the hooking part 380a, which prevents the tab cover 120 from falling out of the receiving part 360 of the upper plate 320. .

In FIG. 9B, the fastening protrusion 126 is provided on the tab cover 120 and the fastening groove 380 is provided on the upper plate 320, but this is merely an example, and in another embodiment, the fastening protrusion 126 is provided on the upper plate. It is provided on the plate 320, and the fastening groove 380 may be provided on the tab cover 120.

In FIG. 9B , the fastening protrusions 126 and fastening grooves 380 are disposed at three positions between the cell assembly 100 and the upper plate 320, but this is merely an example, and at two or less or four or more positions. can be placed.

Referring to FIGS. 9A and 9B , the first electrode tab 111-1 and the second electrode tab 111-2 are connected to different bus bars 370, respectively. For example, the second electrode tab 111-2 is connected to a bus bar 370 connected to an external device (eg, the power relay assembly 2 of FIG. 1), and the first electrode tab 111-1 is connected to another It may be connected to the bus bar 370 connected to the battery cell. For another example, the second electrode tab 111-2 is connected to a bus bar 370 connected to another battery cell, and the first electrode tab 111-1 is connected to a bus bar 370 connected to another battery cell. can be connected

In one embodiment, the bus bar 370 may be integrally provided with the pack housing 300. In one embodiment, a portion of the bus bar 370 may be provided in a state of being inserted into the upper plate 320 . For example, when molding the upper plate 320, the inside of the mold may be filled with resin in a liquid state while the bus bar 370 is positioned inside the mold. As the resin hardens, the bus bar 370 is firmly coupled to the upper plate 320 . The upper plate 320 is made of an insulating material such as plastic and is electrically insulated from the bus bar 370.

In one embodiment, when the cell assembly 100 is inserted into the receiving portion 360 of the upper plate 320, the battery cell 110 may be electrically connected to the bus bar 370. In one embodiment, at least a portion of the bus bar 370 may be exposed to the accommodating portion 360 . When the tab cover 120 is inserted into the accommodating portion 360, the electrode tab 111 exposed through the opening 122 of the tab cover 120 is attached to the bus bar 370 disposed in the accommodating portion 360. can be connected

Referring to FIG. 10 , the bus bar 370 is exposed to the two accommodating parts 360 and electrically connects the two cell assemblies 100 respectively accommodated in the two accommodating parts 360 .

In the embodiment shown in FIG. 10, two battery cells 110 are connected through one bus bar 370, but this is merely an example, and in another embodiment, three or more battery cells 110 are connected to one bus bar. It can be connected through the bar 370. For example, a total of six battery cells 110 may be connected through one bus bar 370 . In this case, the bus bar 370 may be connected to positive tabs of the three battery cells 110 and negative tabs of the remaining three battery cells 110 .

Referring to FIGS. 9A and 9B , in one embodiment, the battery cells 110 are disposed on the lower plate 310, and the heat dissipation member 400 is positioned between the battery cell 110 and the lower plate 310. can The heat dissipation member 400 may guide heat generated from the battery cell 110 to quickly escape to the lower plate 310 . In addition, it is possible to guide the stable fixation of the battery cells 110 on the lower plate 310 . The heat dissipation member 400 may include a thermal resin having high thermal conductivity and insulating properties. For example, the thermal resin may include silicone, urethane, or epoxy.

Although not shown, when the tab cover 120 is inserted into the accommodating portion 360 of the upper plate 320, an additional additional layer is added to ensure a stable electrical connection between the bus bar 370 and the electrode tab 111. Configurations can be placed. For example, a conductive adhesive may be disposed between the bus bar 370 and the electrode tab 111 .

9A to 10, the bus bar 370 disposed on the upper plate 320 is not visible from the outside of the battery pack 1, but this is only an example, and in another embodiment, the bus bar 370 It may be exposed to the upper side of the upper plate 320 . That is, the bus bar 370 may be visible from the outside of the pack housing 300 . In this case, after the upper plate 320 is inserted into the cell assemblies, the bus bar 370 may be welded to the electrode tab 111 through the bus bar 370 exposed to the outside of the upper plate 320 .

In the illustrated embodiment, two electrode tabs 111-1 and 111-2 are drawn from one battery cell 110, but the embodiment of this document is not limited thereto, and in another embodiment, one battery cell At 110, three or more electrode tabs may be drawn upward. For example, two negative electrode tabs and two positive electrode tabs may be drawn out from the upper side of the cell body 112 . In this case, the tab cover 120 can accommodate all four electrode tabs. In addition, some or all of the four positive electrode tabs may be exposed to the upper side of the tab cover 120 .

11A shows the elastic member 500 disposed between the battery cells 110 in the first embodiment. 11B shows the elastic member 500 disposed between the battery cells 110 in the second embodiment. 11A and 11B are cross-sectional views of the battery pack 1 of FIG. 1 taken along line III-III'.

In the case of a lithium polymer pouch-type secondary battery, an internal electrolyte is decomposed as a side reaction of repetitive charging and discharging, and gas may be generated. At this time, a phenomenon in which the outer shape of the secondary battery cell is deformed by the generated gas is referred to as a swelling phenomenon. In order to prevent this swelling phenomenon, an elastic member 500 may be disposed between the battery cells 110 and the battery cells 110 .

Referring to FIGS. 11A and 11B , the battery cells 110 may receive pressing force in the arrangement direction. For example, end plates 351 and 352 disposed on both sides of the cell assemblies 100 may press the battery cells 110 inward. The elastic member 500 is disposed between the mutually facing surfaces of the neighboring battery cells 110 so that the pressure applied by the end plate 350 is evenly distributed to the battery cells 110, and the deformation due to swelling is reduced to some extent. it absorbs

Referring to FIG. 11A , the elastic member 500 may include a member made of a soft elastic material such as EPDM (Ethlene Propylene Diene Monomer) rubber, adhesive foam, or polyurethane foam.

Referring to FIG. 11B , the elastic member 500 may be provided in the form of a metal plate. For example, the elastic member 500 may include an aluminum plate. The elastic member 500 may include concavo-convex portions to facilitate elastic deformation. As the elastic member 500 includes the uneven portion, an air layer 520 may be formed between the elastic member 500 and the cell body 112 .

Meanwhile, in the embodiments of this document, the battery cell 110 has been described as having a lithium polymer battery shape, but the embodiments of this document are not limited thereto, and in other embodiments, the battery cell 110 may have various shapes. . For example, the battery cell 110 may include a prismatic cell or a cylindrical cell.

In the above, the configuration and characteristics of the present invention have been described based on the embodiments according to the present invention, but the present invention is not limited thereto, and various changes or modifications can be made within the spirit and scope of the present invention. It is apparent to those skilled in the art, and therefore such changes or modifications are intended to fall within the scope of the appended claims.

1: battery pack 100: cell assembly
110: battery cell 111: electrode tab
120: tab cover 121: tab receiving part
122: opening 123: inner bus bar
126: fastening protrusion 300: pack housing
310: lower plate 320: upper plate
330: front plate 340: rear plate
350: end plate 360: receiving portion
370: bus bar 380: fastening groove
400: heat dissipation member 500: elastic member

Claims (16)

pack housing; and
A plurality of cell assemblies accommodated inside the pack housing; includes,
At least one of the plurality of cell assemblies includes a battery cell and a tab cover coupled to the battery cell,
The pack housing includes a receiving portion configured to accommodate at least a portion of the tab cover.
battery pack. In paragraph 1,
The battery cell includes a cell body and an electrode tab drawn out from the cell body, and the tab cover is coupled to the electrode tab.
battery pack. In paragraph 2,
The electrode tab is inserted inside the tab cover, and the tab cover is configured to expose a part of the electrode tab to the outside of the tab cover.
battery pack. In paragraph 2,
The battery cell includes two or more electrode tabs drawn upward from the cell body.
battery pack. In paragraph 4,
The tab cover is coupled to an upper portion of the battery cell,
The pack housing includes an upper plate disposed above the plurality of cell assemblies, and the receiving portion is provided on the upper plate.
battery pack. In paragraph 5,
A bus bar disposed on the upper plate and electrically connected to the battery cell when the tab cover is accommodated in the accommodating part;
battery pack. In paragraph 6,
A part of the bus bar is exposed to the receiving part,
battery pack. In paragraph 6,
A part of the bus bar is inserted inside the upper plate,
battery pack. In paragraph 8,
The bus bar is configured to electrically connect two or more cell assemblies,
battery pack. In paragraph 5,
One of the upper plate or the tab cover includes a fastening protrusion, and the other one includes a fastening groove for accommodating the fastening protrusion.
battery pack. In paragraph 2,
The tab cover includes an internal bus bar connected to the electrode tab.
battery pack. In paragraph 1,
The cell assembly includes two or more battery cells, and the tab cover is coupled to the two or more battery cells.
battery pack. In paragraph 1,
Further comprising: an elastic member disposed between the plurality of cell assemblies;
battery pack. In paragraph 1,
The pack housing includes a lower plate disposed below the plurality of cell assemblies, and a heat dissipation member is disposed between the battery cell and the lower plate.
battery pack. pack housing;
a plurality of battery cells disposed inside the pack housing; and
A tab cover coupled to an electrode tab of at least one battery cell among the plurality of battery cells;
The pack housing includes an accommodating portion configured to accommodate the tab cover and a bus bar disposed in the accommodating portion and connected to the electrode tab when the tab cover is accommodated in the accommodating portion.
battery pack. In clause 15,
The electrode tab includes two or more electrode tabs drawn out in a first direction,
The pack housing includes a plate facing the plurality of battery cells in the first direction and having the accommodating portion and the bus bar.
battery pack.

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