KR20230058852A - Battery Module and Battery Pack Having the same - Google Patents

Abstract

The present invention relates to a battery module (100) and a battery pack including the same. The battery module comprises: a plurality of pouch type battery cells (120); and a bus bar assembly (130). The plurality of pouch type battery cells (120) include: an electrode accommodating unit (122) which accommodates an electrode assembly (127) inside; a sealing unit (123) which seals at least a part of the circumference of the electrode accommodating unit (122); and an electrode lead (125) which is electrically connected to the electrode assembly (127). The bus bar assembly (130) includes a plurality of bus bars (140) which are electrically connected to the electrode lead (125). The electrode lead (125) is arranged in both sides of a longitudinal direction (X1) of the battery cell (120). The bus bar assembly (130) is combined with the battery cell (120) in the both sides of the longitudinal direction (X1) of the battery cell (120). The bus bar (140) includes: a first bus bar (G1) which includes a connection terminal (149) provided for electrical connection with the outside; and a second bus bar (G2) which connects the electrode lead (125) of different polarities which are not adjacent to each other. The second bus bar (G2) includes a plurality of base units (141) in which a combining hole (142) connected to the electrode lead (125) is formed; and a connecting unit (145) which electrically connects the plurality of base units (141) which are not adjacent to each other. The present invention can minimize damage of a connection terminal connecting unit due to external shock.

Description

Battery module and battery pack having the same {Battery Module and Battery Pack Having the same}

The present invention relates to a battery module including a plurality of pouch-type battery cells and a battery pack including the same.

Unlike primary batteries, secondary batteries can be charged and discharged, so they can be applied to various fields such as digital cameras, mobile phones, laptop computers, hybrid vehicles, and electric vehicles. Secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-hydrogen batteries, lithium secondary batteries, and the like.

Among these secondary batteries, many studies on lithium secondary batteries having high energy density and discharge voltage are in progress. Recently, a lithium secondary battery is manufactured as a pouch type battery cell having flexibility or a prismatic or cylindrical can type battery cell having rigidity, and a plurality of battery cells are electrically connected and used. At this time, a plurality of battery cells form a cell stack in a stacked form and are disposed inside the module housing to form a battery module.

The battery module includes bus bars connected to electrode leads of the battery cells to connect a plurality of battery cells in series/parallel, and negative/positive connection terminals (high voltage terminals) connected to the bus bars. The connection terminal is exposed to the outside of the battery module to provide electrical connection with the outside.

In the case of a battery module having a structure in which a plurality of battery cells are stacked so that the wide surfaces of the battery cells face each other in battery cells in which electrode leads are formed on both sides in the longitudinal direction, the connection terminals are Placement may vary. For example, the positive/negative electrode connection terminals are exposed from both ends of one side of the module housing corresponding to one side of the battery cell in the longitudinal direction, or the positive/negative electrode is connected from both sides of the module housing corresponding to both sides of the battery cell in the longitudinal direction. Each of the terminals is exposed so that the positive connection terminal and the negative connection terminal may be located in a diagonal direction of the battery module.

As such, the battery module of the prior art having a pouch-type battery cell inevitably has a structure in which connection terminals are exposed at both ends of one side of the module housing or exposed in a diagonal direction at the other side opposite to each other. Accordingly, the battery module according to the prior art has a problem in that the change of the arrangement position of the connection terminal is limited.

In addition, in the case of the prior art, when connecting terminals between a plurality of battery modules in a battery pack through a terminal connecting member (external bus bar), the distance between the connecting terminals to be connected to each other increases, resulting in a long length of the terminal connecting member. have to lose Accordingly, the battery pack according to the prior art has a problem in that the layout of the terminal connection members is complicated and the size and weight of the terminal connection members are large due to an increase in length.

KR 2021-0048976 A

The present invention has been made to solve at least some of the problems of the prior art as described above, and for a pouch type battery cell in which electrode leads are disposed on both sides in the longitudinal direction of the battery cell, the connection terminal is disposed on one side of the battery cell in the stacking direction. It is an object of the present invention to provide a battery module that can do this and a battery pack having the same.

In addition, as an aspect of the present invention, it is an object of the present invention to provide a battery pack in which the arrangement structure (layout) of terminal connection members connecting the connection terminals of neighboring battery modules is simple, and the size and weight can be reduced. do.

And, as one aspect of the present invention, an object of the present invention is to provide a battery pack capable of minimizing damage or damage to a connection terminal connection portion in the event of an external impact.

As one aspect for achieving at least some of the above objects, the present invention provides an electrode accommodating portion for accommodating an electrode assembly therein, a sealing portion for sealing at least a portion of the circumference of the electrode accommodating portion, and an electrical connection with the electrode assembly. A plurality of pouch-type battery cells each including an electrode lead connected to; and a bus bar assembly including a plurality of bus bars electrically connected to the electrode leads, wherein the electrode leads are disposed on both sides of the battery cell in the longitudinal direction, and the bus bar assembly is disposed on both sides in the longitudinal direction of the battery cell. is coupled to the battery cell, and the bus bar includes a first bus bar having a connection terminal provided for electrical connection with the outside, and a second bus bar connecting the electrode leads of different polarities that are not adjacent to each other. The second bus bar provides a battery module having a plurality of base parts having coupling holes connected to the electrode leads and a connection part electrically connecting the plurality of base parts that are not adjacent to each other.

A plurality of battery cells are stacked to form a cell stack, and the connection terminals are respectively disposed on both sides of the battery cells in the longitudinal direction, and are positioned to correspond to each other on one side of the cell stack based on the stacking direction of the battery cells. can be placed in

In addition, in the cell stack, a length of the battery cells in a stacking direction may have a value greater than a length of the battery cells in a longitudinal direction.

The first bus bar may include a terminal connection portion electrically connecting the electrode lead and the connection terminal, and the terminal connection portion may have a stepped structure to be spaced apart from the second bus bar. In this case, an insulating member may be installed between the terminal connection part and the second bus bar.

In addition, the connection part electrically connects a plurality of base parts that are not adjacent to each other, and the second bus bar may have a U-shape.

The second bus bar includes a lower connection bus bar in which the connection portion is formed on a lower side of the base portion and an upper connection bus bar in which the connection portion is formed on an upper side of the base portion, and the upper connection bus bar and the lower connection bus bar are at least They may be arranged alternately in some areas.

In addition, the thickness of the connection part may have a greater value than the thickness of the base part.

Meanwhile, the bus bar assembly may include an insulating support plate on which the bus bar is installed, and the support plate may include partition protrusions formed to protrude between adjacent bus bars.

The connection part may include a first connection part positioned on the same plane as the base part, and a second connection part bent from the first connection part and extending toward the battery cell. Here, the second bus bar includes a lower connection bus bar where the connection part is formed on the lower side of the base part and an upper connection bus bar where the connection part is formed on the upper side of the base part, and the first connection part and the second connection part have the upper side connection part. It may be provided on the connection bus bar. In addition, the thickness of the connection part provided in the lower connection bus bar may have a greater value than the thickness of the connection part provided in the upper connection bus bar, and the total area of the connection part provided in the lower connection bus bar may be greater than the thickness of the connection part provided in the upper connection bus bar. It may have a value smaller than the total area of the connecting portion provided in the bar.

Also, the first connection part and the second connection part may have the same thickness as the base part.

The support plate may include a first body portion in which the first connection portion is disposed, and a second body portion extending from the first body portion toward the battery cell so that the second connection portion is disposed.

In addition, the height of the electrode lead connected to the upper connection bus bar may have a greater value than the height of the electrode lead connected to the lower connection bus bar.

Also, the bus bar may be configured to serially connect an odd number of the battery cells. The second bus bar may connect the plurality of electrode leads in parallel or in series.

On the other hand, the present invention as another aspect, the above-described battery module; a pack housing accommodating the battery module; and a terminal connection member electrically connecting the connection terminals of the battery module, wherein a plurality of battery cells are stacked to form a cell stack, and the connection terminals are respectively disposed on both sides of the battery cells in a longitudinal direction. , Based on the stacking direction of the battery cells, it provides battery packs disposed at positions corresponding to each other, leaning on one side of the cell stack.

Here, in the battery module, the connection terminal may be disposed in a central portion rather than an outer portion of the pack housing.

The terminal connection member may be connected to the connection terminal at a position lower than a height of the battery module.

According to one embodiment of the present invention having such a configuration, it is possible to obtain an effect that the connection terminals can be disposed on one side of the stacking direction of the battery cell with respect to the pouch type battery cell in which the electrode leads are disposed on both sides in the longitudinal direction of the battery cell. .

In addition, according to an embodiment of the present invention, the arrangement structure (layout) of the terminal connection member connecting the connection terminals of the neighboring battery modules to each other is simple, and the size and weight can be reduced.

And, according to an embodiment of the present invention, it is possible to obtain an effect of minimizing damage or damage to the connection terminal connection portion due to external impact.

1 is a perspective view of a battery module according to a first embodiment of the present invention;
2 is an exploded perspective view illustrating a state in which a bus bar assembly is separated from a cell stack after removing a module housing for the battery module shown in FIG. 1;
3 is a perspective view of a pouch type battery cell according to an embodiment of the present invention.
Figure 4 (a) is an enlarged view of the "A" portion of Figure 2, (b) is a cross-sectional view taken along line II' of (a), (c) is a deformation along line II' of (a) Cross section showing an example.
(a) of FIG. 5 is an enlarged view of part "B" of FIG. 2, and (b) is a cross-sectional view taken along line II-II' of (a).
6 is a cross-sectional view taken along line III-III' of (a) of FIG. 4;
Fig. 7 is a schematic diagram showing electricity flow for the battery module shown in Figs. 1 and 2;
8 is a perspective view of a battery module according to a second embodiment of the present invention.
9 is an exploded perspective view illustrating a state in which a bus bar assembly is separated from a cell stack after removing a module housing with respect to the battery module shown in FIG. 8;
Figure 10 (a) is an enlarged view of the "C" portion of Figure 9, (b) is a cross-sectional view taken along line IV-IV' of (a).
Fig. 11 is a schematic diagram showing electricity flow for the battery module shown in Figs. 8 and 9;
12 is a front view showing a modified example of a bus bar assembly according to an embodiment of the present invention.
13 is a perspective view illustrating an example of a battery cell to which the bus bar assembly shown in FIG. 12 is connected;
14 is a schematic diagram showing a plan view of a battery pack according to an embodiment of the present invention;
15 is a cross-sectional view taken along line VV' of FIG. 14;
16 and 17 are schematic views showing a plane of a battery pack according to the prior art.

Prior to the detailed description of the present invention, the terms or words used in this specification and claims described below should not be construed as being limited to a common or dictionary meaning, and the inventors should use their own invention in the best way. It should be interpreted as a meaning and concept corresponding to the technical idea of the present invention based on the principle that it can be properly defined as a concept of a term for explanation. Therefore, the embodiments described in this specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and do not represent all of the technical ideas of the present invention, so various equivalents that can replace them at the time of the present application. It should be understood that there may be water and variations.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. At this time, it should be noted that the same components in the accompanying drawings are indicated by the same reference numerals as much as possible. In addition, detailed descriptions of well-known functions and configurations that may obscure the gist of the present invention will be omitted. For the same reason, some components in the accompanying drawings are exaggerated, omitted, or schematically illustrated, and the size of each component does not entirely reflect the actual size.

First, the battery module 100 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 7 .

1 is a perspective view of a battery module 100 according to a first embodiment of the present invention, and FIG. 2 is a bus bar assembly 130 after removing the module housing 150 with respect to the battery module 100 shown in FIG. is an exploded perspective view showing a state separated from the cell stack 110, and FIG. 3 is a perspective view of the pouch type battery cell 120 according to an embodiment of the present invention. In addition, (a) of FIG. 4 is an enlarged view of part “A” of FIG. 2, (b) is a cross-sectional view taken along the line II' of (a), and (c) is the line I-I' of (a). Figure 5 (a) is an enlarged view of the "B" portion of Figure 2, (b) is a cross-sectional view taken along line II-II' of (a), Figure 6 is a cross-sectional view showing a modified example according to the It is a cross-sectional view taken along line III-III' of (a) of FIG. 4, and FIG. 7 is a schematic diagram showing the flow of electricity in the battery module 100 shown in FIGS. 1 and 2. 1 shows the module housing 150 in a projected state so that the inside of the battery module 100 can be checked, and FIG. 7 shows the support plate 131 removed to clarify the shape of the bus bar 140. state is shown.

1 and 2, the battery module 100 according to an embodiment of the present invention is a plurality of pouch-type battery cells 120 and a bus bar assembly electrically connecting the plurality of battery cells 120 ( 130) may be included.

A plurality of battery cells 120 are stacked to form the cell stack 110 . The cell stack 110 and the bus bar assembly 130 are accommodated inside the module housing 150 .

The module housing 150 forms an internal space in which the battery cell 120 is accommodated by combining the first housing 151 and the second housing 152, and the first housing 151 and the second housing 152 The open end of may be closed by an end plate (155). In FIG. 1, the module housing 150 is shown as divided into a first housing 151 and a second housing 152 each having a U-shaped cross section, but the first housing 151 and the second housing 152 ) can be changed in various ways. In addition, it is also possible that the first housing 151 and the second housing 152 are integrally formed.

The bus bar assembly 130 may include a bus bar 140 electrically connected to the battery cell 120 and an insulating support plate 131 on which the bus bar 140 is installed.

The bus bar 140 may have connection terminals 149 provided for electrical connection with the outside, and the connection terminals 149 are external to the module housing 150 so as to be connected to external devices such as the battery module 100. can be exposed as The bus bar 140 includes a first bus bar G1 having a connection terminal 149 connected to the battery cell 120, a non-adjacent battery cell 120 or a non-adjacent battery cell of a parallel structure ( 120) may be provided with a second bus bar (G2) connecting them in series. In addition, the bus bar 140 may include a third bus bar G3 connecting adjacent battery cells 120 or parallel structured battery cells 120 in series. Here, the parallel structure battery cells 120 refer to a group of battery cells 120 in which electrode leads 125 of the same polarity are connected to each other through a bus bar 140 .

The supporting plate 131 is attached to the insulating body 132 so that the insulating body 132 on which the bus bar 140 is installed and the electrode lead ( 125 in FIG. 3 ) of the battery cell 120 can be connected to the bus bar 140. A through hole 133 formed therethrough may be provided.

In addition, the connection terminals 149 are disposed on both sides of the battery cell 120 in the longitudinal direction (X1), and are biased toward one side of the cell stack 110 based on the stacking direction (X2) of the battery cell 120 and correspond to each other. can be placed in a location that

Referring to FIG. 3 , the battery cell 120 provided in the present invention is composed of a pouch type secondary battery, and may have a structure in which an electrode lead 125 protrudes to the outside.

The battery cell 120 may be configured in a form in which the electrode assembly 127 is accommodated in a pouch 121 forming an exterior material. The electrode assembly 127 includes a plurality of electrode plates (not shown) and electrode tabs (not shown) and is housed in the pouch 121 . Here, the electrode plate is composed of a positive electrode plate and a negative electrode plate, and the electrode assembly 127 may be configured in a form in which the positive electrode plate and the negative electrode plate are stacked with a separator interposed therebetween in a state in which wide surfaces of the positive electrode plate and the negative electrode plate face each other. The positive electrode plate and the negative electrode plate are formed as a structure in which an active material slurry is applied to a current collector, and the slurry may be formed by stirring a granular active material, an auxiliary conductor, a binder, and a plasticizer in a state in which a solvent is added. Also, in the electrode assembly 127 , a plurality of positive electrode plates and a plurality of negative electrode plates are stacked in the thickness direction X2 of the battery cell 120 . At this time, electrode tabs are provided on each of the plurality of positive electrode plates and the plurality of negative electrode plates, and the electrode tabs may be connected to the electrode leads 125 having the same polarity by contacting each other with the same polarity. That is, the electrode lead 125 may be electrically connected to the electrode plate of the electrode assembly 127 through the electrode tab.

And, the pouch 121 is formed in a container shape to provide an internal space in which the electrode assembly 127 and an electrolyte solution (not shown) are accommodated. At this time, a portion of the electrode lead 125 may be exposed to the outside of the pouch 121 .

The pouch 121 may be divided into an electrode accommodating part 122 and a sealing part 123 . The electrode accommodating portion 122 is formed in a container shape and provides a space in which the electrode assembly 127 and the electrolyte are accommodated.

The sealing portion 123 is a portion of the pouch 121 joined to seal the circumference of the accommodating portion 122 . Therefore, the sealing part 123 is formed in the form of a flange extending outward from the accommodating part 122 formed in the form of a container, and is disposed along the outer circumference of the accommodating part 122 . A thermal fusion method may be used to join the pouch 121 to form the sealing portion 123, but is not limited thereto.

In addition, in this embodiment, the sealing part 123 may be divided into a first sealing part 123a where the electrode lead 125 is disposed and a second sealing part 123b where the electrode lead 125 is not disposed. .

In this embodiment, the pouch 121 may be formed by forming a sheet of exterior material. More specifically, the pouch 121 may be completed by forming one or two storage units on a sheet of packaging material, and then folding the packaging material so that the storage units form one space (that is, the storage unit 122).

In this embodiment, the accommodating part 122 may be formed in a square shape. In addition, a sealing portion 123 formed by joining an exterior material to the outer portion of the accommodating portion 122 is provided. However, as described above, it is not necessary to form the sealing portion 123 on the folded surface of the exterior material. Therefore, in this embodiment, the sealing part 123 is formed on the outside of the accommodating part 122, provided only on three surfaces of the accommodating part 122, and any one of the outer surfaces of the accommodating part 122 (the lower part in FIG. 3). surface), the sealing part 123 may not be disposed.

In this embodiment, the electrode leads 125 are disposed on both sides of the battery cell 120 in the longitudinal direction X1 so as to face opposite directions. An electrode lead 125 of a first polarity (eg, positive electrode) is disposed on one side of the battery cell 120 in the longitudinal direction, and an electrode lead 125 of a second polarity (eg, negative electrode) is disposed on the other side in the longitudinal direction. is placed The two electrode leads 125 are disposed on the sealing part 123 formed on different sides. Therefore, the sealing part 123 of this embodiment consists of two first sealing parts 123a where the electrode lead 125 is disposed and one second sealing part 123b where the electrode lead 125 is not disposed. do. In FIG. 3 , the second sealing portion 123b is illustrated as being formed on the upper surface of the pouch 121 , but the second sealing portion 123b may also be formed on the lower surface of the pouch 121 .

On the other hand, the pouch 121 used in the embodiment of the present invention is not limited to a structure in which a sealing portion 123 is formed on three sides by folding a sheet of exterior material, as shown in FIG. 3 . For example, it is also possible to form the accommodating portion 122 by overlapping two sheets of exterior materials, and to form the sealing portion 123 on all four surfaces around the accommodating portion 122 . In this case, the sealing part 123 may be composed of two first sealing parts 123a on which the electrode leads 125 are disposed, and two second sealing parts 123b on which the electrode leads 125 are not disposed. there is. In this case, the second sealing portion 123b may be formed on the upper and lower surfaces of the battery cell 120 .

In addition, in the battery cell 120 of the present embodiment, in order to increase reliability of bonding of the sealing portion 123 and to minimize an area of the sealing portion 123, the sealing portion 123 may be formed in a folded shape at least once.

More specifically, among the sealing parts 123 according to the present embodiment, the second sealing part 123b on which the electrode lead 125 is not disposed may be fixed by the adhesive member 124 after being folded twice. For example, the second sealing part 123b may be folded 180° along the first bending line C1 and then again folded along the second bending line C2 shown in FIG. 3 . At this time, the adhesive member 124 may be filled inside the second sealing portion 123b, and the second sealing portion 123b may maintain a twice-folded shape by the adhesive member 124. The adhesive member 124 may be formed of an adhesive having high thermal conductivity. For example, the adhesive member 124 may be formed of epoxy or silicone, but is not limited thereto.

The battery cell 120 configured as described above may be a nickel metal hydride (Ni-MH) battery or a lithium ion (Li-ion) battery capable of charging and discharging.

These battery cells 120 are disposed in the inner space of the module housing 150, and a plurality of battery cells 120 are vertically erected in the inner space of the module housing 150 and stacked in the left and right directions so that the cell stack 110 ) will be achieved.

The bus bar assembly 130 will be described in more detail with reference to FIGS. 4 to 6 together with FIG. 2 . The bus bar assemblies 130 are disposed on both sides of the cell stack in the longitudinal direction (X1), and are coupled to the electrode leads 125 of the battery cells 120 on both sides of the battery cell 120 in the longitudinal direction (X1), respectively. do.

As shown in FIG. 2, the bus bar assembly 130 includes a bus bar 140 electrically connected to the battery cell 120 and an insulating support on which the bus bar 140 is installed. A plate 131 may be included. The bus bar 140 is a second bus bar connecting a first bus bar G1 having a connection terminal 149 provided for electrical connection with the outside and electrode leads 125 of different polarities that are not adjacent to each other. (G2) may be included. In addition, the bus bar 140 may include a third bus bar G3 connecting the electrode leads 125 of different polarities adjacent to each other.

In addition, the connection terminals 149 have a structure disposed on both sides of the longitudinal direction (X1) of the battery cell 120, and one side ( In FIG. 2, they may be disposed at positions corresponding to each other, biased in the +X2 direction).

Meanwhile, in order to increase the capacity of the battery module 100, it is necessary to increase the number of battery cells 120 constituting the cell stack 110. To this end, the cell stack 110 is stacked in the stacking direction of the battery cells 120 The length (X2) may have a greater value than the length of the battery cell 120 in the longitudinal direction (X1). Accordingly, in the battery module 100, the stacking direction X2 of the battery cells 120 becomes a long direction, and the connection terminals 149 are biased toward one side of the stacking direction X2 on both sides of the battery module 100 in the long direction. position can be placed.

2 and 4, the second bus bar G2 includes a plurality of base parts 141 having coupling holes 142 connected to electrode leads 125, and a plurality of base parts not adjacent to each other ( 141 may be provided with a connecting portion 145 that electrically connects them.

At least one electrode lead 125 may be coupled to the base portion 141 . In addition, in the battery cell 120, electrode leads 125 of different polarities are disposed on both sides in the longitudinal direction, and the base portion 141 of the second bus bar G2 includes a plurality of electrode leads 125 of the same polarity in parallel. can connect

For example, in FIG. 4 , four coupling holes 142 are formed in the base portion 141, and electrode leads 125 may be coupled to each coupling hole 142. Accordingly, the base part 141 may connect the electrode leads 125 of the four battery cells 120 in parallel. However, the number of battery cells 120 connected in parallel in the base part 141 can be changed in various ways.

The base parts 141 provided in the second bus bar G2 are spaced apart from each other, and the spaced base parts 141 may be connected by a connection part 145 . That is, the connection part 145 electrically connects the plurality of base parts 141 that are not adjacent to each other.

In addition, the connection part 145 electrically connects the base part 141 to which the electrode leads 125 having different polarities are coupled to connect the battery cells 120 in series. At this time, a plurality of electrode leads 125 are coupled to each base part 141 to connect a plurality of battery cells 120 in parallel, and the connection part 145 has a structure in which each base part 141 is connected in series. Therefore, the second bus bar G2 implements a series/parallel connection structure between the battery cells 120. That is, the second bus bar G2 connects the plurality of electrode leads 125 in parallel and in series.

The connection part 145 connects the spaced base parts 141 to each other through a space above or below the adjacent base part 141 . At this time, the connection parts 145 of the plurality of second bus bars G2 need not overlap each other. To this end, the second bus bar G2 is connected to the lower connection bus bar GA, in which the connection part 145 is formed on the lower side of the base part 141, and the upper connection part 145 is formed on the upper side of the base part 141. It can be classified as a bus bar (GB).

In addition, the upper connection bus bar GB and the lower connection bus bar GA may be alternately disposed in at least a portion of the area so that the connection parts 145 do not overlap each other. For example, in the embodiment of FIG. 2 , the second bus bar G2 is composed of three upper connection bus bars GB and two lower connection bus bars GA, and includes the upper connection bus bar GB and the lower connection bus bar G2. Connection busbars GA may be alternately disposed over the entire area where the second busbar G2 is installed. However, if the connection part 145 of the upper connection bus bar GB and the connection part 145 of the lower connection bus bar GA do not overlap each other, in some of the areas where the second bus bar G2 is installed, the upper side It is also possible that the connection bus bar GB or the lower connection bus bar GA is continuously provided (see FIG. 9).

In addition, the second bus bar G2 is configured to connect the two base parts 141 and may have a U-shape as a whole (including an inverted U-shape).

Since the base part 141 connects a plurality of electrode leads 125 in parallel, and the connection part 145 is configured to connect base parts 141 that are not adjacent to each other in series, a large amount of current can flow through the connection part 145. there is.

When the cross-sectional area of the connection portion 145 is small, the electrical resistance of the connection portion 145 increases, and accordingly, the amount of heat generated increases, which may cause electrical loss and the temperature of the battery cell 120 due to the temperature rise of the bus bar 140. can bring rise. An increase in the temperature of the battery cell 120 may cause a decrease in efficiency of the battery cell 120 and may cause various problems such as an explosion due to overheating of the battery cell 120 .

In view of this point, in the embodiment of the present invention, as shown in (b) and (c) of FIG. It may have a value greater than the thickness t1 of the portion 141. That is, resistance and heat generation of the connecting portion 145 can be reduced by increasing the thickness of the connecting portion 145 . In order to increase the thickness t2 of the connecting portion 145, the second bus bar G2 may be formed through forging, but the forming method of the second bus bar G2 is not limited thereto.

In addition, for electrical insulation between the bus bars 140 adjacent to each other, the support plate 131 protrudes to partition between the bus bars 140 adjacent to each other, as shown in FIG. 4(c). A protrusion 134 may be provided. The partition protrusion 134 may have a protruding structure integrally formed with the insulating body 132 of the support plate 131, but an insulating material for insulation is applied between the bus bars 140 or an insulating member is installed. Various changes may be made.

Referring to FIG. 5, the first bus bar G1 includes a base portion 141 to which an electrode lead 125 of a battery cell 120 is coupled, a connection terminal 149 provided for electrical connection with the outside, A terminal connection portion 148 connecting the base portion 141 and the connection terminal 149 may be included.

At this time, the terminal connecting portion 148 may have a stepped structure spaced apart from the second bus bar G2 by a predetermined distance D1 so as not to be electrically connected to the second bus bar G2. In addition, in order to improve insulation between the terminal connection part 148 and the second bus bar G2, an electrical insulating insulating member S may be installed between the terminal connection part 148 and the second bus bar G2. The insulating member S may have a structure applied or inserted between the terminal connecting portion 148 and the second bus bar G2. However, when the arrangement of the terminal connection part 148 and the second bus bar G2 do not overlap, the terminal connection part 148 may be configured to contact the support plate 131 .

The terminal connection unit 148 is the connection terminal on the opposite side so that the connection terminals 149 disposed on both sides of the cell in the longitudinal direction (X1) are disposed at positions corresponding to each other with respect to the stacking direction (X2) of the battery cell 120. It may have a structure extending to a position corresponding to (149).

Referring to FIG. 6 , the bus bar assembly 130 may include an electrically insulating support plate 131 on which the bus bar 140 is installed. The base part 141 mounted on the support plate 131 may include a conductive base body 141a having a coupling hole 142 through which the electrode lead 125 is coupled.

The combination of the electrode lead 125 and the base part 141 is a state in which the electrode lead 125 penetrates the coupling hole 142 of the base body 141a, that is, the electrode lead 125 is outside the base body 141a. It can be performed by welding in a state in which it protrudes into.

In addition, the support plate 131 supports the base portion 141 through the insulating body 132 , and a through hole 133 through which the electrode lead 125 passes may be formed in the insulating body 132 . In addition, the support plate 131 may include partition protrusions 134 protruding to block electrical connections between adjacent bus bars 140 by partitioning between adjacent bus bars 140 .

Next, the flow of electricity in the battery module 100 according to the first embodiment of the present invention will be described with reference to FIG. 7 .

The bus bar 140 includes a first bus bar G1 connected to the connection terminal 149, a second bus bar G2 connecting electrode leads 125 of different polarities that are not adjacent to each other, and other adjacent bus bars G2. It may be configured to include a third bus bar (G3) connecting the electrode lead 125 of the polarity.

Since the third bus bar G3 has an integral structure to which the base parts 141 of different polarities are directly connected, it does not have a structure corresponding to the connection part 145 of the second bus bar G2. In addition, a plurality of electrode leads ( 125 in FIG. 6 ) of different polarities may be coupled to the base portion 141 of the third bus bar G3 . For example, FIG. 7 shows a configuration in which eight coupling holes (142 in FIG. 6) are formed in the base portion 141, and the four coupling holes 142 provided on one side of the base portion 141 have It may have a structure in which four electrode leads 125 having a first polarity are coupled and four electrode leads 125 having a second polarity are coupled to the four coupling holes 142 provided on the other side. Accordingly, the third bus bar G3 connects a plurality of battery cells in a parallel structure in series.

In addition, the connection terminal 149 has a first polarity (eg, positive electrode) and a second polarity (eg, negative electrode) that are different from each other, and each connection terminal 149 is in the longitudinal direction of the battery cell 120 ( X1) placed on both sides.

Arrows ① to ⑬ in FIG. 7 show sequential electricity flows in numerical order. First, electricity flows from the connection terminal 149 provided on the first bus bar G1 on one side through the battery cell 120 to the second bus bar G2 on the other side (①). Thereafter, electricity flows through the base part 141 of the second bus bar G2 on both sides and the battery cell 120 connected therebetween (② to ⑥). In this process, the connection part of the second bus bar G2 Through 145, electric flow is transmitted to base parts 141 that are not adjacent to each other. When electricity is supplied from the second bus bar G2 on one side to the outer end of the third bus bar G3 on the other side via the battery cell 120 (⑦), the inner end of the third bus bar G3 and the Electricity flows to the second bus bar G2 through the connected battery cell 120 (⑧). Thereafter, electricity flows through the base part 141 of the second bus bar G2 on both sides and the battery cell 120 connected therebetween (⑨ to ⑫). Electric flow is transferred to base parts 141 that are not adjacent to each other through the connection part 145 . Finally, electricity flows through the second bus bar G2 and the battery cell 120 connected thereto to the connection terminal 149 provided to the first bus bar G1 on the other side (⑬).

The electrode lead 125 of the first polarity (eg, anode) may be coupled to the bus bar 140 provided at the starting point of the arrow corresponding to ① to ⑬ in FIG. 7, and the bus bar provided at the end point of the arrow An electrode lead 125 of a second polarity (eg, cathode) may be coupled to the bar 140 .

Although FIG. 7 shows a structure in which battery cells 120 are grouped in parallel by four and a total of 13 battery cell groups are connected in series, the number of battery cells 120 forming unit groups connected in parallel and in series The number of groups of connected battery cells may be variously changed.

However, the connection terminals 149 are disposed on both sides of the longitudinal direction (X1) of the battery cell 120, and are biased toward one side of the cell stack 110 based on the stacking direction (X2) of the battery cell 120 to correspond to each other. An odd number of battery cells 120 (battery cell group) connected in series by the first bus bar G1 , the second bus bar G2 , and the third bus bar G3 may be configured in order to be disposed at the position. can

Next, the battery module 100 according to the second embodiment of the present invention will be described with reference to FIGS. 8 to 11 .

8 is a perspective view of the battery module 100 according to the second embodiment of the present invention, and FIG. 9 is a bus bar assembly 130 after removing the module housing 150 with respect to the battery module 100 shown in FIG. 8 is an exploded perspective view showing a state separated from the cell stack 110, FIG. 10 (a) is an enlarged view of the “C” portion of FIG. 9, and (b) is an IV-IV′ line of (a) 11 is a schematic diagram showing the flow of electricity with respect to the battery module 100 shown in FIGS. 8 and 9 . 8 shows the module housing 150 in a projected state so that the inside of the battery module 100 can be checked, and FIG. 11 shows the support plate 131 removed to clarify the shape of the bus bar 140. state is shown.

The second embodiment of the battery module 100 shown in FIGS. 8 to 11 has the same or corresponding configuration as the first embodiment shown in FIGS. 1 to 7, except for the shape of the bus bar assembly 130. There is a difference. Therefore, in order to avoid unnecessary duplication, among the configurations of the battery module 100 according to the second embodiment, the same reference numerals are shown for components identical to or corresponding to those of the first embodiment, and detailed descriptions thereof will be omitted. The description will be centered on the composition.

8 and 9, the battery module 100 according to an embodiment of the present invention is a plurality of pouch-type battery cells 120 and a bus bar assembly electrically connecting the plurality of battery cells 120 ( 130) may be included. A plurality of battery cells 120 are stacked to form the cell stack 110 . The cell stack 110 and the bus bar assembly 130 are accommodated inside the module housing 150 . The bus bar assembly 130 may include a bus bar 140 electrically connected to the battery cell 120 and an insulating support plate 131 on which the bus bar 140 is installed.

9 and 10, the bus bar 140 is connected to the first bus bar G1 having the connection terminal 149 connected to the battery cell 120 and the battery cell 120 that is not adjacent to each other or to each other. A second bus bar G2 may be provided to serially connect non-adjacent battery cells 120 in a parallel structure. In addition, the bus bar 140 may include a third bus bar G3 connecting adjacent battery cells 120 or parallel structured battery cells 120 in series.

The second bus bar G2 is a connecting portion electrically connecting a plurality of base portions 141 having coupling holes 142 connected to electrode leads 125 and a plurality of base portions 141 that are not adjacent to each other ( 145) may be provided.

The connection part 145 provided on at least a part of the second bus bar G2 is bent from the first connection part 146 located on the same plane as the base part 141 and the first connection part 146 to form the battery cell ( 120) may be provided with a second connection portion 147 extending toward the side. Since the connection part 145 of the second bus bar G2 includes the second connection part 147, the total area of the connection part 145 can be increased, thereby reducing the electrical resistance of the connection part 145 and generating heat. be able to reduce To correspond to the shape of the second bus bar G2, the support plate 131 includes a first body portion 132a on which the first connecting portion 146 is disposed, and a first body portion on which the second connecting portion 147 is disposed. A second body portion 132b extending from 132a toward the battery cell 120 may be provided.

In addition, the second bus bar G2 includes a lower connection bus bar GA having a connection part 145 formed on the lower side of the base part 141 and an upper connection bus having the connection part 145 formed on the upper side of the base part 141. A bar (GB) may be provided. In this case, the first connection part 146 and the second connection part 147 may be provided in the upper connection bus bar GB to increase the total area of the connection part 145 .

Unlike the upper connection bus bar GB in which the second connection portion 147 is formed, the lower connection bus bar GA does not have a configuration corresponding to the second connection portion 147, so the connection portion ( 145) becomes small. In order to reduce the electrical resistance of the lower connection bus bar GA, as shown in (b) of FIG. 10, the thickness t2 of the connection portion 145 provided in the lower connection bus bar GA is It may have a value greater than the thickness t1 and the thickness t3 of the connection portion 145 provided in the upper connection bus bar GB. On the other hand, since the total area of the first connection part 146 and the second connection part 147 can be increased, they can be formed to have the same thickness t3 as the thickness t1 of the base part 141 . However, the thicknesses of the first connection portion 146 and the second connection portion 147 are not limited thereto, and various changes are possible in consideration of the area and electrical resistance of the connection portion 145 .

As such, in the case of the second embodiment of the present invention, the upper connection bus bar GB increases the total area of the connection portion 145, and the lower connection bus bar GA increases the thickness t2 of the connection portion 145. By doing so, it is possible to reduce electrical resistance and heat generated from the connection portion 145 .

However, the second embodiment of the present invention is not limited to the configuration shown in FIGS. 8 to 10, and the first connection part 146 and the second connection part 147 are the upper connection bus bar GB and the lower connection bus It is also possible that all of them are provided in the bar GA. In addition, the first connection part 146 and the second connection part 147 are provided in the lower connection bus bar GA to increase the total area of the connection part 145, and the upper connection bus bar GB is connected to the connection part 145 It is also possible to change to increase the thickness of.

In FIG. 11, arrows ① to ⑬ show the sequential flow of electricity in numerical order, and as described with reference to FIG. 7, from the connection terminal 149 on one side to the first bus bar G1 and the second bus bar G2 , A sequential electrical flow may be formed between the third bus bar G3.

Next, with reference to FIGS. 12 and 13 , modifications of the bus bar assembly 130 and the battery cell 120 coupled thereto will be described.

12 is a front view showing a modified example of a bus bar assembly 130 according to an embodiment of the present invention, and FIG. 13 is an example of a battery cell 120 to which the bus bar assembly 130 shown in FIG. 12 is connected. It is a perspective view showing

The bus bar assembly 130 shown in FIG. 12 and the battery cell 120 shown in FIG. 13 have the same or corresponding configuration as the bus bar assembly 130 of the first embodiment described through FIGS. 1 to 7, However, only the shape of the bus bar 140 and the position of the electrode lead 125 of the battery cell 120 are different. Therefore, in order to avoid unnecessary duplication, the same reference numerals are shown for components identical to or corresponding to those of the first embodiment, detailed descriptions will be omitted, and only components with differences will be described.

In the bus bar assembly 130 shown in FIG. 12, the second bus bar G2 is a lower connection bus bar GA in which the connection part 145 is formed on the lower side of the base part 141, and the connection part 145 is the base part. An upper connection bus bar (GB) formed on the upper side of (141) is provided. Here, the base part 141 of the upper connection bus bar GB is connected to the electrode lead 125 of the battery cell 120 at a higher position than the base part 141 of the lower connection bus bar GA. The base part 141 of the lower connection bus bar GA is configured to be connected to the electrode lead 125 of the battery cell 120 at a higher position than the base part 141 of the upper connection bus bar GB. Accordingly, the height of the connection part 145 of the lower connection bus bar GA positioned below the base part 141 of the upper connection bus bar GB can be increased, and similarly, the base part of the lower connection bus bar GA can be increased. (141) The height of the connection part 145 of the upper connection bus bar GB located at the upper part can be increased. That is, compared to the case where the heights of the base portions 141 of the upper connection bus bar GB and the lower connection bus bar GA are constant, the embodiment of FIG. 12 has a larger space in the height direction for forming the connection portion 145. do. Therefore, in the case of the second bus bar G2 shown in FIG. 12 , by increasing the height of the connecting portion 145 , the total area of the connecting portion 145 is increased, thereby reducing electrical resistance. Therefore, since the total area of the connecting portion 145 is increased compared to the first embodiment, electrical resistance can be reduced without greatly increasing the thickness.

In order to be coupled to the bus bar 140 shown in FIG. 12, the battery cell 120 has a height H1 of one electrode lead 125 as shown in FIG. It may have a height lower than the height H2. That is, the electrode leads 125 located on both sides of the battery cell 120 may have different heights. At this time, the height H2 of the electrode lead 125 connected to the upper connection bus bar GB may have a greater value than the height H1 of the electrode lead 125 connected to the lower connection bus bar GA. .

Next, the battery pack 200 according to an embodiment of the present invention will be described with reference to FIGS. 14 to 17 .

14 is a schematic diagram showing a plane of a battery pack 200 according to an embodiment of the present invention, FIG. 15 is a cross-sectional view taken along line V-V′ of FIG. 14, and FIGS. 16 and 17 are battery packs according to the prior art ( 10) is a schematic diagram showing a plane.

Referring to FIG. 14 , a battery pack 200 according to an embodiment of the present invention is configured to accommodate a plurality of battery modules 100 and a plurality of battery modules 100 previously described with reference to FIGS. 1 to 13 . It is configured to include a pack housing 210. Also, the battery pack 200 may include a terminal connection member 220 electrically connecting the connection terminals 149 of the battery module 100 .

As described above, the connection terminals 149 of the battery module 100 according to the embodiment of the present invention are disposed on both sides of the longitudinal direction (X1) of the battery cell 120, respectively, in the stacking direction of the battery cell 120 ( X2), they are disposed on one side of the cell stack 110 and correspond to each other.

Accordingly, when the plurality of battery modules 100 are installed in the pack housing 210, the connection terminals 149 of different polarities may be arranged to face each other, so that the connection terminals 149 of different polarities are interconnected. The terminal connection member 220 may have a very short straight shape.

In this regard, in the battery pack 10 according to the prior art, a plurality of battery modules 20 are installed inside the pack housing 30, and the long sides of the battery modules are on both sides in the longitudinal direction (corresponding to the X direction) of the battery cells. is formed As shown in FIG. 16 , the prior art battery pack 10 may have a structure in which the connection terminals 21 of the battery module 20 are exposed from both ends of the long side of the battery module 20 . Alternatively, the prior art battery pack 10 may have a structure in which the connection terminals 21 of the battery module 20 are exposed from both sides of the long side of the battery module 20 as shown in FIG. 17 . In the case of FIG. 17 , the connection terminal 21 of the battery module 20 has a structure positioned in a diagonal direction of the battery module 20 . Therefore, in the battery pack 10 according to the prior art, not only is the arrangement structure of the terminal connection members 22 complicated, but also the length of the terminal connection members 22 increases, resulting in increased weight and installation cost.

However, in the battery pack 200 according to the embodiment of the present invention, since the terminal connection member 220 has a straight and very short shape, the arrangement structure (layout) of the terminal connection member 220 is simple, and the terminal connection member ( 220) can have the advantage of reducing the size, weight, and manufacturing cost.

In addition, in the embodiment of the present invention, the battery module 100 may be disposed so that the connection terminal 149 is located in the central portion C of the pack housing 210 rather than the outside. When the connection terminal 149 is adjacent to the center of the pack housing 210, even if an external shock is applied to the battery pack 200 due to a vehicle collision, damage or damage to the connection terminal connection portion 148 can be minimized. In particular, according to the embodiment of the present invention, when an impact is applied to the battery pack 200 or the vehicle in the width direction (Y), since the connection terminal 149 is not located at a portion adjacent to the outside in the width direction (Y), FIG. As shown in FIGS. 16 and 17 , damage to the connection terminals can be minimized compared to the case where the connection terminals 22 are adjacent to the outside of the pack housing 30 .

In addition, as shown in FIG. 15 , the terminal connection member 220 may be configured to be connected to the connection terminal 149 at a position lower than the height of the battery module 100 . In this case, since the terminal connection member 220 is not located in the upper space of the battery module 100 or the volume occupied in the upper space can be minimized, the space in the height direction (Z) of the battery pack 200 can be reduced, and the battery The energy density per the same volume of the pack 200 can be increased.

Although the 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 variations are possible without departing from the technical spirit of the present invention described in the claims. It will be obvious to those skilled in the art.

For example, it may be implemented by deleting some components from the above-described embodiments, and each embodiment may be implemented in combination with each other.

100 ... battery module 110 ... cell stack
120... battery cell 130... busbar assembly
140... busbar 150... module housing
200... battery pack 210... pack housing
220... terminal connection member G1... first bus bar
G2... 2nd bus bar G3... 3rd bus bar
GA... bottom connection busbar GB... top connection busbar

Claims (20)

A plurality of pouch-type battery cells each including an electrode accommodating portion accommodating an electrode assembly therein, a sealing portion sealing at least a portion of a circumference of the electrode accommodating portion, and an electrode lead electrically connected to the electrode assembly; and
a bus bar assembly having a plurality of bus bars electrically connected to the electrode leads;
Including,
The electrode leads are disposed on both sides of the battery cell in the longitudinal direction,
The bus bar assembly is coupled to the battery cell at both sides in the longitudinal direction of the battery cell,
The bus bar includes a first bus bar having a connection terminal provided for electrical connection with the outside and a second bus bar connecting the electrode leads of different polarities that are not adjacent to each other,
The second bus bar includes a plurality of base portions having coupling holes connected to the electrode leads, and a connection portion electrically connecting the plurality of base portions that are not adjacent to each other. According to claim 1,
A plurality of battery cells are stacked to form a cell stack,
The connection terminals are disposed on both sides of the battery cells in the longitudinal direction, respectively, and are disposed at positions corresponding to each other, biased toward one side of the cell stack based on the stacking direction of the battery cells. According to claim 2,
The battery module of claim 1 , wherein a length of the battery cells in a stacking direction of the cell stack has a value greater than a length of the battery cells in a longitudinal direction. According to claim 1,
The first bus bar has a terminal connection portion electrically connecting the electrode lead and the connection terminal,
The battery module having a stepped structure so that the terminal connection portion is spaced apart from the second bus bar. According to claim 4,
A battery module in which an insulating member is installed between the terminal connection portion and the second bus bar. According to claim 1,
The connection part electrically connects a plurality of the base parts that are not adjacent to each other,
The second bus bar has a U-shaped battery module. According to claim 1,
The second bus bar includes a lower connection bus bar where the connection part is formed on the lower side of the base part and an upper connection bus bar where the connection part is formed on the upper side of the base part,
The upper connection bus bar and the lower connection bus bar are alternately disposed in at least a portion of the battery module. According to claim 1,
The battery module having a thickness greater than the thickness of the base portion. According to claim 1,
The bus bar assembly has an insulating support plate on which the bus bar is installed,
The battery module wherein the support plate has partition protrusions protruding to partition between the bus bars adjacent to each other. According to claim 1,
The battery module comprising: a first connection part positioned on the same plane as the base part; and a second connection part bent from the first connection part and extending toward the battery cell. According to claim 10,
The second bus bar includes a lower connection bus bar where the connection part is formed on the lower side of the base part and an upper connection bus bar where the connection part is formed on the upper side of the base part,
The first connection part and the second connection part are provided on the upper connection bus bar. According to claim 10,
The second bus bar includes a lower connection bus bar where the connection part is formed on the lower side of the base part and an upper connection bus bar where the connection part is formed on the upper side of the base part,
The battery module wherein the thickness of the connection part provided on the lower connection bus bar has a greater value than the thickness of the connection part provided on the upper connection bus bar. According to claim 10,
The battery module of claim 1 , wherein the first connection part and the second connection part have the same thickness as the base part. According to claim 10,
The bus bar assembly has an insulating support plate on which the bus bar is installed,
The support plate includes a first body portion on which the first connection portion is disposed, and a second body portion extending from the first body portion toward the battery cell so that the second connection portion is disposed thereon. According to claim 1,
The second bus bar includes a lower connection bus bar where the connection part is formed on the lower side of the base part and an upper connection bus bar where the connection part is formed on the upper side of the base part,
A height of the electrode lead connected to the upper connection bus bar has a greater value than a height of the electrode lead connected to the lower connection bus bar. According to claim 1,
The bus bar is configured to connect an odd number of the battery cells in series. According to claim 1,
The second bus bar connects the plurality of electrode leads in parallel and in series.
The battery module according to claim 1;
a pack housing accommodating the battery module; and
a terminal connection member electrically connecting the connection terminals of the battery module;
Including,
A plurality of battery cells are stacked to form a cell stack,
The connection terminals are respectively disposed on both sides of the battery cells in the longitudinal direction, and are disposed at corresponding positions on one side of the cell stack based on the stacking direction of the battery cells. According to claim 18,
The battery pack of the battery module, wherein the connection terminal is disposed in a central portion of the pack housing rather than an outer side thereof. According to claim 18,
The terminal connection member is connected to the connection terminal at a position lower than the height of the battery module.

Images