Battery pack

Abstract

According to one aspect of the present invention, there is provided a battery pack including: a plurality of battery cells having first and second electrode terminals; a case in which the plurality of battery cells are accommodated; a first cell module and a second cell module, each including a first connection tab connected to the first electrode terminal and exposed to a first end side of the case, and a second connection tab connected to the second electrode terminal and extending to an outside of a second end of the case opposite the first end; and a circuit board unit electrically connecting the first cell module and the second cell module with the first cell module and the second cell module arranged in order, wherein the first cell module and the second cell module are arranged such that the second connection tab of the first cell module is positioned on the first connection tab of the second cell module, and the circuit board unit is positioned on the second connection tab of the first cell module and is electrically connected to the first connection tab of the second cell module via the second connection tab of the first cell module.

Description

[Technical Field]

[0001] The present invention relates to a battery pack, and more particularly to a battery pack that can reduce the number of welding operations during the assembly process of a battery pack configured with a plurality of cell modules.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0182097, dated December 22, 2022, and all contents disclosed in the documents of this Korean patent application are incorporated herein by reference. [Background technology]

[0003] Among secondary batteries, lithium secondary batteries with high energy density and discharge voltage have been the subject of much research and have been commercialized and widely used. Depending on the type of external device used, secondary batteries are used in the form of a single cell or in the form of a battery pack in which multiple battery cells are electrically connected.

[0004] For example, small devices such as mobile phones can operate for a certain period of time with the output and capacity of a single battery, whereas medium- to large-sized devices such as laptops, power tools, and hybrid electric vehicles require the use of medium- to large-sized battery packs due to output and capacity issues.A battery pack consists of multiple battery cells connected in series and / or parallel.

[0005] 1 to 3 are diagrams illustrating the structure of a battery pack according to the prior art.

[0006] FIG. 1 is a plan view of a battery pack 1 according to the prior art, and FIG. 2 is a perspective view of cell modules 10, 20 according to the prior art.

[0007] FIG. 3 is a cross-sectional view taken along line AA in FIG. 1, illustrating the process of welding the circuit board portion to the two cell modules.

[0008] As shown in FIGS. 1 to 3, a conventional battery pack 1 includes a plurality of cell modules 10, 20 and a circuit board 30.

[0009] For ease of explanation, the multiple cell modules 10, 20 are referred to as the first cell module 10 and the second cell module 20 according to their arrangement order. The first cell module 10 and the second cell module 20 have the same structure. In Fig. 1, the y-axis direction indicates the longitudinal direction of the battery cell (or case), and the z-axis direction indicates the radial direction of the battery cell (or case).

[0010] 2 and 3, the first cell module 10 includes a case 11, a battery cell 13, a first tab portion 15, and a second tab portion 17. The first tab portion 15 is electrically connected to the battery cell 13 on one side of the case 11 and is provided to contact the outer circumferential surface of the case 11. The second tab portion 17 is electrically connected to the battery cell 13 on the other side of the case 11 and is provided to contact the outer circumferential surface of the case 11.

[0011] The second cell module 20 includes a case 21, a battery cell 23, a first tab portion 25, and a second tab portion 27. The first tab portion 25 is electrically connected to the battery cell 23 on one side of the case 21 and is provided to contact the outer circumferential surface of the case 21. The second tab portion 27 is electrically connected to the battery cell 23 on the other side of the case 21 and is provided to contact the outer circumferential surface of the case 21.

[0012] As shown in Figure 3, when the first cell module 10 and the second cell module 20 are arranged in a row in the longitudinal direction Y of the battery cell 13, the second tab portion 17 of the first cell module 10 is positioned adjacent to the first tab portion 25 of the second cell module 20.

[0013] The circuit board 30 is stacked so as to cover the second tab portion 17 of the first cell module 10 and the first tab portion 25 of the second cell module 20 along a direction z different from the longitudinal direction of the battery cell 13, i.e., the radial direction of the battery cell, which is a direction perpendicular to the longitudinal direction Y of the battery cell 13.

[0014] The first cell module 10 and the second cell module 20 are electrically connected via a circuit board 30, and the circuit board 30 has a plurality of connectors 33, each of which is electrically connected to the first cell module 10 and the second cell module 20.

[0015] 3, welding beam W is applied to circuit board 30 at a position where circuit board 30 is stacked on second tab portion 17 of first cell module 10. Subsequently, welding beam B is applied to circuit board 30 at a position where circuit board 30 is stacked on first tab portion 25 of second cell module 20.

[0016] As a result, the connector 33 of the circuit board 30 is electrically connected to the second tab portion 17 of the first cell module 10 and the first tab portion 25 of the second cell module 20 through two welding operations.

[0017] In the assembly process of a conventional battery pack 1, at least two welding processes are required per connector 33 to connect two cell modules 10 and 20, and the number of welding processes increases as the number of connected cell modules 10 and 20 increases. Summary of the Invention [Problem to be solved by the invention]

[0018] An object of the present invention is to provide a battery pack that can reduce the number of welding operations when welding a circuit board part that electrically connects multiple cell modules by changing the structure of connection tabs that are connected to battery cells. [Means for solving the problem]

[0019] In order to solve the above-mentioned problems, a battery pack according to one embodiment of the present invention includes a plurality of battery cells having first and second electrode terminals, a case in which the plurality of battery cells are accommodated, a first cell module and a second cell module, each including a first connection tab connected to the first electrode terminal and exposed at a first end of the case, and a second connection tab connected to the second electrode terminal and extending outward from a second end of the case opposite the first end.

[0020] The battery pack also includes a circuit board unit that electrically connects the first cell module and the second cell module when the first cell module and the second cell module are arranged in order.

[0021] In addition, the first cell module and the second cell module may be arranged so that the second connection tab of the first cell module is positioned on the first connection tab of the second cell module, and the circuit board part may be positioned on the second connection tab of the first cell module and electrically connected to the first connection tab of the second cell module via the second connection tab of the first cell module.

[0022] In addition, the first connecting tab may have a first tab portion that contacts the first electrode terminal at the first end of the case, and a first bent portion that is bent at the first tab portion and contacts the outer peripheral surface of the first end of the case.

[0023] The second connection tab may have a second tab portion that contacts the second electrode terminal at the second end of the case, and a second bent portion that is bent at the second tab portion and extends outside the second end.

[0024] In addition, the first tab portion may extend along a radial direction of the battery cell, and the first bent portion may extend along a longitudinal direction of the battery cell.

[0025] In addition, the second tab portion may extend along a radial direction of the battery cell, and the second bent portion may extend along a longitudinal direction of the battery cell.

[0026] The first tab portion and the first bent portion may be disposed so as to intersect at right angles, and the second tab portion and the second bent portion may be disposed so as to intersect at right angles.

[0027] The first bent portion may extend along the longitudinal direction of the case from the first end to the second end, and the second bent portion may extend along the longitudinal direction of the case from the first end to the second end.

[0028] The first bent portion and the second bent portion may be arranged in parallel.

[0029] The second connecting tab may be provided such that an inner surface of the second bent portion is positioned on the same virtual plane as an outer surface of the first bent portion.

[0030] In addition, the case may have at least one groove on an outer peripheral surface of the first end portion, and the first connecting tab may have the first tab portion electrically connected to the first electrode terminal and the first bent portion seated in the groove.

[0031] The first connecting tab may be configured such that an outer surface of the first bent portion is exposed to the outside of the case when the first bent portion is seated in the groove.

[0032] In addition, the second connecting tab may be configured such that the inner surface of the second bent portion is positioned on the same virtual plane as the outer surface of the case, and the outer surface of the second bent portion may be positioned a predetermined distance away from the outer surface of the case.

[0033] Furthermore, when the first cell module and the second cell module are arranged in sequence in the longitudinal direction of the battery cell, the second tab portion of the second connection tab provided on the first cell module may be spaced apart from the first tab portion of the first connection tab provided on the second cell module, and the second bent portion of the second connection tab provided on the first cell module may be positioned on the first bent portion of the first connection tab provided on the second cell module.

[0034] Furthermore, the circuit board portion may be positioned on the first cell module and the second cell module so that the connector covers the second bent portion, and the connector may be welded to the second bent portion of the first cell module and the first bent portion of the second cell module.

[0035] In addition, the first bent portion of the second cell module, the second bent portion of the first cell module, and the circuit board unit may be stacked in a direction different from the longitudinal direction of the battery cell.

[0036] The circuit board unit may be a flexible printed circuit board (FPCB), and a control circuit for controlling the charging and discharging of each cell module may be provided on the circuit board unit.

[0037] The circuit board unit may include a plurality of connectors, and the connectors may be made of a metal material. [Effects of the Invention]

[0038] As described above, the battery pack according to one aspect of the present invention has the following effects.

[0039] In the conventional battery pack assembly process, at least two welding processes are required per connector of the circuit board to connect two cell modules. In contrast, the present invention allows two cell modules to be electrically connected with one welding process per connector of the circuit board during the battery pack assembly process by modifying the structure of the connection tab.

[0040] Specifically, the second connection tab protruding from the other side of the first cell module may be stacked on the first connection tab provided on one side of the second cell module, and then the circuit board unit may be stacked on the second connection tab. At this time, the connector of the circuit board unit may be welded once to the second connection tab of the first cell module and the first connection tab of the second cell module, thereby electrically connecting the first cell module and the second cell module.

[0041] Compared with the conventional battery pack assembly process, the present invention can reduce the number of welding steps in the battery pack assembly process by half, thereby shortening the battery pack assembly process time.

[0042] Furthermore, the battery pack assembly process time can be shortened, ultimately increasing the productivity of the battery pack. [Brief explanation of the drawings]

[0043] [Figure 1] FIG. 1 is a schematic plan view of a battery pack according to the prior art. [Figure 2] FIG. 1 is a schematic perspective view of a cell module according to the prior art. [Figure 3] 2 is a cross-sectional view taken along line AA in FIG. 1, illustrating the process of welding a circuit board portion to two cell modules. FIG. [Figure 4] 1 is a diagram schematically illustrating a plan view of a battery pack according to an embodiment of the present invention; [Figure 5] FIG. 5 is a cross-sectional view taken along the line BB in FIG. 4, illustrating the process of welding the circuit board portion to the two cell modules. [Figure 6] FIG. 2 is a diagram schematically showing an assembled cross-sectional view of a first cell module according to one embodiment of the present invention. [Figure 7] FIG. 2 is a diagram schematically showing an assembled cross-sectional view of a second cell module according to one embodiment of the present invention. [Figure 8]FIG. 2 is a diagram schematically illustrating a perspective view of a first cell module and a second cell module coupled together according to one embodiment of the present invention. [Figure 9] FIG. 1 is a diagram schematically showing a perspective view of a first cell module (second cell module) according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0044] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A battery pack according to an embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

[0045] Furthermore, regardless of the drawing symbols, identical or corresponding components will be given the same or similar reference numbers, and duplicate descriptions thereof will be omitted. For convenience of explanation, the size and shape of each component shown may be exaggerated or reduced.

[0046] FIG. 4 is a plan view schematically illustrating a battery pack according to an embodiment of the present invention, and FIG. 5 is a cross-sectional view taken along line BB in FIG. 4, illustrating a process of welding a circuit board unit to two cell modules.

[0047] A battery pack 1000 according to an embodiment of the present invention includes a plurality of cell modules 100, 200, 300, and 400, and a circuit board unit 500 for electrically connecting two adjacent cell modules 100, 200, 300, and 400. The circuit board unit 500 may be a flexible printed circuit board (FPCB).

[0048] The circuit board unit 500 may be provided with a control circuit for controlling the discharge or charge / discharge of each of the cell modules 100, 200, 300, and 400, and the circuit board unit 500 may include a plurality of connectors 530, each of which is electrically connected to two adjacent cell modules 100 and 200, and the connectors 530 may be made of a metal material.

[0049] Each cell module 100, 200, 300, 400 has the same structure, and for the convenience of the following explanation, the multiple cell modules 100, 200 will be divided and referred to as a first cell module 100 and a second cell module 200 according to the arrangement order of the multiple cell modules 100, 200, and the electrical connection structure between the first cell module 100 and the second cell module 200 will be explained using an example.

[0050] FIG. 6 is a diagram showing a schematic cross-sectional assembly view of a first cell module according to one embodiment of the present invention, and FIG. 7 is a diagram showing a schematic cross-sectional assembly view of a second cell module according to one embodiment of the present invention.

[0051] Furthermore, Figure 8 is a diagram schematically showing an oblique view of the combination of a first cell module and a second cell module according to one embodiment of the present invention, and Figure 9 is a diagram schematically showing an oblique view of the first cell module (second cell module) according to one embodiment of the present invention.

[0052] As shown in FIGS. 4 and 8, the first cell module 100 and the second cell module 200 are arranged in a row in the longitudinal direction (Y-axis direction) of the battery cell.

[0053] In this specification, the y-axis direction indicates the longitudinal direction of the battery cell (or case), and the z-axis direction indicates the radial direction of the battery cell (or case).

[0054] The first cell module 100 and the second cell module 200 have the same structure. In this specification, the same components are designated by the same names, and the components provided in the first cell module 100 and the second cell module 200 are designated by different drawing numbers.

[0055] The battery pack 1000 includes a first cell module 100 and a second cell module 200, and each cell module (first cell module 100, second cell module 200) includes a plurality of battery cells having first and second electrode terminals, a case in which the plurality of battery cells are accommodated, a first connection tab connected to the first electrode terminal and exposed at a first end of the case, and a second connection tab connected to the second electrode terminal and extending outward from a second end of the case opposite the first end.

[0056] Also, the first and second connection tabs may be made of a metal material having electrical conductivity.

[0057] Referring to FIGS. 5 and 6, the first cell module 100 may include a case 110, a plurality of battery cells 130, a first connection tab 150, a second connection tab 170, and a support rib 190.

[0058] Referring to FIGS. 5 and 7, the second cell module 200 may include a case 210, a plurality of battery cells 230, a first connection tab 250, a second connection tab 270, and a support rib 290.

[0059] 6, in the first cell module 100, the case 110 has a tubular structure that is open in the longitudinal direction Y of the battery cell. The case 110 has at least one groove 115 formed on the outer circumferential surface on the first end 113 side.

[0060] The plurality of battery cells 130 are each housed in the internal space 112 of the case 110. Each battery cell 130 has a first electrode terminal 131 and a second electrode terminal 132. In the first cell module 100, each battery cell can be arranged such that the first electrode terminal 131 faces the first end 113 of the case 110, and the second electrode terminal 132 faces the second end 114 of the case.

[0061] The support rib 190 is mounted in the internal space 112 of the case 110. The support rib 190 supports the battery cells 130 so that the battery cells 130 are spaced apart from each other inside the case 110.

[0062] The first connection tab 150 is connected to the first electrode terminal 131 and is exposed on the first end 113 side of the case 110. Here, the first electrode terminal 131 may be a positive electrode or a negative electrode, and the second electrode terminal 132 may have a polarity opposite to that of the first electrode terminal 131.

[0063] The first connecting tab 150 has a first tab portion 151 and a first bent portion 155 bent at the first tab portion 151. Specifically, the first connecting tab 150 has the first tab portion 151 that contacts the first electrode terminal 131 at the first end 113 side of the case 110, and the first bent portion 155 that is bent at the first tab portion 151 and contacts the outer peripheral surface 111 of the case 110 at the first end 113 side.

[0064] The first tab portion 151 may extend along a radial direction (z-axis direction) of the battery cell 130, and the first bent portion 155 may extend along a longitudinal direction (y-axis direction) of the battery cell 130. For example, the first tab portion 151 and the first bent portion 155 may be disposed to be perpendicular to each other.

[0065] The first connecting tab 150 is attached to the case 110 so that the first tab portion 151 contacts the first electrode terminal 131 on the first end 113 side of the case 110 and the first bent portion 155 contacts the outer peripheral surface 111 on the first end 113 side of the case 110.

[0066] The first connecting tab 150 is attached to the case 110 such that the first bent portion 155 is seated in the groove 115. An inner surface 157 of the first bent portion 155 contacts the groove 115.

[0067] When the first bent portion 155 of the first connecting tab 150 is seated in the groove 115, the outer surface 158 of the first bent portion 155 and the outer surface 111 of the case 110 may be located on the same imaginary plane L1.

[0068] The second connection tab 170 is electrically connected to the second electrode terminal 132 and extends to the outside of the second end 114 of the case 110 , which is opposite to the first end 113 .

[0069] The second connecting tab 170 has a second tab portion 171 and a second bent portion 175 bent at the second tab portion 171. Specifically, the second connecting tab 170 has the second tab portion 171 that contacts the second electrode terminal 132 at the second end portion 114 of the case 110, and the second bent portion 175 that is bent at the second tab portion 171 and extends outside the second end portion 114.

[0070] The second tab portion 171 may extend along the radial direction (z-axis direction) of the battery cell 130, and the second bent portion 175 may extend along the longitudinal direction (y-axis direction) of the battery cell 130. For example, the second tab portion 171 and the second bent portion 175 may be arranged to be perpendicular to each other.

[0071] The second connecting tab 170 may be attached to the case 110 such that the second tab portion 171 contacts the second electrode terminal 132 at the second end 114 of the case 110 and the second bent portion 175 extends outside the second end 114.

[0072] The second connecting tab 170 may be attached to the case 110 such that the inner surface 177 of the second bent portion 175 and the outer surface 158 of the first bent portion 155 are placed on the same imaginary plane L1.

[0073] The second connecting tab 170 can be attached to the second end 114 side of the case 110 so that the inner surface 177 of the second bent portion 175 is placed on the same virtual plane L1 as the outer surface 111 of the case 110, and the outer surface 178 of the second bent portion 175 is stepped relative to the outer surface 111 of the case.

[0074] 7, in the second cell module 200, the case 210 has a tubular structure that is open in the longitudinal direction Y of the battery cell. The case 210 has at least one groove 215 formed on the outer circumferential surface on the first end 213 side.

[0075] The plurality of battery cells 230 are each housed in the internal space 212 of the case 210. Each battery cell 230 has a first electrode terminal 231 and a second electrode terminal 232. In the second cell module 200, each battery cell can be arranged such that the first electrode terminal 231 faces the first end 213 of the case 210 and the second electrode terminal 232 faces the second end 214 of the case 210.

[0076] The support rib 290 is mounted in the internal space 212 of the case 210. The support rib 290 supports the battery cells 230 so that the battery cells 230 are spaced apart from each other inside the case 210.

[0077] The first connection tab 250 is connected to the first electrode terminal 231 and is exposed on the first end 213 side of the case 210. Here, the first electrode terminal 231 may be a positive electrode or a negative electrode, and the second electrode terminal 232 may have a polarity opposite to that of the first electrode terminal 231.

[0078] The first connecting tab 250 has a first tab portion 251 and a first bent portion 255 bent at the first tab portion 251. Specifically, the first connecting tab 250 has the first tab portion 251 that contacts the first electrode terminal 231 at the first end 213 side of the case 210, and the first bent portion 255 that is bent at the first tab portion 251 and contacts the outer circumferential surface 211 of the case 210 at the first end 213 side.

[0079] The first tab portion 251 may extend along a radial direction (z-axis direction) of the battery cell 230, and the first bent portion 255 may extend along a longitudinal direction (y-axis direction) of the battery cell 230. For example, the first tab portion 251 and the first bent portion 255 may be disposed to be perpendicular to each other.

[0080] The first connecting tab 250 may be attached to the case 210 such that the first tab portion 251 contacts the first electrode terminal 231 on the first end 213 side of the case 210 and the first bent portion 255 contacts the outer peripheral surface 211 on the first end 213 side of the case 210.

[0081] The first connecting tab 250 is attached to the case 210 such that the first bent portion 255 is seated in the groove 215. An inner surface 257 of the first bent portion 255 contacts the groove 215.

[0082] When the first bent portion 255 of the first connecting tab 250 is seated in the groove 215, the outer surface 258 of the second bent portion 255 may be positioned on the same imaginary plane L1 as the outer surface 211 of the case 210.

[0083] The second connection tab 270 is electrically connected to the second electrode terminal 232 and extends to the outside of the second end 214 of the case 210 , which is opposite to the first end 213 .

[0084] The second connecting tab 270 has a second tab portion 271 and a second bent portion 275 bent at the second tab portion 271. Specifically, the second connecting tab 270 has the second tab portion 271 that contacts the second electrode terminal 232 at the second end portion 214 of the case 210, and the second bent portion 275 that is bent at the second tab portion 271 and extends outside the second end portion 214.

[0085] The second tab portion 271 may extend along the radial direction (z-axis direction) of the battery cell 230, and the second bent portion 275 may extend along the longitudinal direction (y-axis direction) of the battery cell 230. For example, the second tab portion 271 and the second bent portion 275 may be disposed to be perpendicular to each other.

[0086] The second connection tab 270 may be attached to the case 210 such that the second tab portion 271 contacts the second electrode terminal 232 at the second end 214 of the case 210 and the second bent portion 275 extends outside the second end 214.

[0087] The second connecting tab 270 may be attached to the case 210 such that the inner surface 277 of the second bent portion 275 and the outer surface 258 of the first bent portion 255 are placed on the same imaginary plane L1.

[0088] The second connecting tab 270 can be attached to the second end 214 side of the case 210 so that the inner surface 277 of the second bent portion 275 is placed on the same virtual plane L1 as the outer surface 211 of the case 210, and the outer surface 278 of the second bent portion 275 is stepped relative to the outer surface 211 of the case 210.

[0089] The joining structure of the circuit board unit 500 to the first cell module 100 and the second cell module 200 will be described below.

[0090] The battery pack 1000 includes a circuit board unit 500 that electrically connects the first cell module 100 and the second cell module 200 in a state in which the first cell module 100 and the second cell module 200 are arranged in order.

[0091] 4 and 8, the first cell module 100 and the second cell module 200 are arranged in order in the longitudinal direction Y of the battery cell.

[0092] 5 to 9, when the first cell module 100 and the second cell module 200 are sequentially arranged in the longitudinal direction Y of the battery cell, the second tab portion 171 of the second connection tab 170 provided in the first cell module 100 is spaced apart from the first tab portion 251 of the first connection tab 250 provided in the second cell module 200. The second bent portion 175 of the second connection tab 170 provided in the first cell module 100 is disposed on the first bent portion 255 of the first connection tab 250 provided in the second cell module 200.

[0093] 5 and 6, the first connecting tab 250 provided in the second cell module 200 may be arranged such that the outer surface of the first bent portion 255 and the outer surface of the case 210 are located on the same imaginary plane L1.

[0094] The second bent portion 175 of the second connection tab 170 of the first cell module 100 is stacked on the first bent portion 255 of the first connection tab 250 of the second cell module 200 in a direction (z) different from the longitudinal direction (y-axis direction) of the battery cell. At this time, the inner surface 177 of the second bent portion 175 of the first cell module 100 may come into contact with the outer surface 258 of the first bent portion 255 of the second cell module 200.

[0095] The circuit board unit 500 is disposed on the first cell module 100 and the second cell module 200 so as to cover the second bent portion 175 of the first cell module 100. In particular, the circuit board unit 500 is disposed so that the connector 530 covers the second bent portion 175 of the first cell module 100.

[0096] The circuit board unit 500 electrically connects the first cell module 100 and the second cell module 200, and a flexible printed circuit board (FPCB) may be used as the circuit board unit 500.

[0097] Referring to FIG. 5, the circuit board unit 500 has the connector 530 positioned on the second connection tab 170 of the first cell module 100, and the connector 530 can be electrically connected to the first connection tab 250 of the second cell module 200 via the second connection tab 170 of the first cell module 100.

[0098] As shown in FIG. 5, the first bent portion 155 of the second cell module 200, the second bent portion 175 of the first cell module 100, and the circuit board portion 300 are stacked in a direction (z-axis direction) different from the longitudinal direction (y-axis direction) of the battery cell.

[0099] Here, the second bent portion 175 protruding from the other side of the first cell module 100 is disposed between the first bent portion 255 of the first connection tab 250 disposed on one side of the second cell module 200 and the circuit board portion 500.

[0100] That is, the circuit board unit 500 is placed on the first cell module 100 and the second cell module 200 so that the connector 530 covers the second bent portion 175, and the connector 530 is welded to the second bent portion 175 of the first cell module 100 and the first bent portion 255 of the second cell module 200.

[0101] The connector 530 of the circuit board unit 500 is welded to the second bent portion 175 of the first cell module 100 and the first bent portion 155 of the second cell module 200. The welding beam W may be irradiated perpendicularly to the circuit board unit 300 in a direction (Z) different from the longitudinal direction of the battery cells.

[0102] In the present invention, the second connection tab 170 protruding from the other side of the first cell module 100 is stacked on the first connection tab 250 provided on one side of the second cell module 200, and then the connector 530 of the circuit board unit 500 is welded once to the second connection tab 170 of the first cell module 100 and the first connection tab 250 of the second cell module 200, thereby electrically connecting the first cell module 100 and the second cell module 200.

[0103] In the conventional battery pack 1 assembly process, at least two welding processes were required to connect two cell modules 10, 20. In contrast, the present invention allows two cell modules 100, 200 to be electrically connected with one welding process per connector 530 during the battery pack 1000 assembly process by changing the structure of the connection tab.

[0104] The above-described preferred embodiments of the present invention have been disclosed for illustrative purposes, and those skilled in the art having ordinary skill in the art may make various modifications, changes, and additions within the spirit and scope of the present invention, and such modifications, changes, and additions should be considered to fall within the scope of the following claims. [Industrial Applicability]

[0105] According to the battery pack according to one embodiment of the present invention, the number of welding operations during the assembly process of the battery pack including a plurality of cell modules can be reduced. [Explanation of symbols]

[0106] 110 cases 130 battery cells 131 1st electrode terminal 132 2nd electrode terminal 150 First connecting tab 170 Second connecting tab 100 First cell module (cell module) 200 Second Cell Module (Cell Module) 500 Circuit board section 1000 battery pack

Claims

1. A battery pack including: a plurality of battery cells having first and second electrode terminals; a case in which the plurality of battery cells are accommodated; a first cell module and a second cell module each including a first connection tab connected to the first electrode terminal and exposed at a first end of the case; and a second connection tab connected to the second electrode terminal and extending outward from a second end of the case opposite the first end, the first cell module and the second cell module are arranged such that a second connection tab of the first cell module is positioned on a first connection tab of the second cell module; The battery pack The battery pack further comprises a circuit board unit positioned on and electrically connected to the second connection tab of the first cell module, the circuit board unit being electrically connected to the first connection tab of the second cell module via the second connection tab of the first cell module, thereby electrically connecting the first cell module and the second cell module when the first cell module and the second cell module are arranged in sequence.

2. The first connecting tab is a first tab portion that contacts the first electrode terminal at a first end of the case; a first bent portion bent at the first tab portion and contacting an outer peripheral surface of the first end portion of the case; and The second connecting tab is a second tab portion that contacts the second electrode terminal at a second end of the case; a second bent portion bent at the second tab portion and extending outward from the second end portion; 10. The battery pack of claim 1, comprising:

3. the first bent portion extends along the longitudinal direction of the case from the first end toward the second end, The battery pack according to claim 2 , wherein the second bent portion extends along the longitudinal direction of the case from the first end toward the second end.

4. The battery pack according to claim 3 , wherein the first bent portion and the second bent portion are arranged in parallel.

5. The battery pack according to claim 3 , wherein the second connecting tab is provided such that an inner surface of the second bent portion is positioned on the same virtual plane as an outer surface of the first bent portion.

6. The case has at least one groove formed on an outer peripheral surface of the first end portion, 6. The battery pack of claim 2, wherein the first connecting tab has the first tab portion electrically connected to the first electrode terminal and the first bent portion seated in the groove.

7. The battery pack of claim 6, wherein the first connecting tab is configured such that an outer surface of the first bent portion is exposed to the outside of the case when the first bent portion is seated in the groove.

8. 3. The battery pack of claim 2, wherein the second connecting tab is provided such that an inner surface of the second bent portion is positioned on the same virtual plane as an outer surface of the case, and the outer surface of the second bent portion is positioned at a predetermined distance from the outer surface of the case.

9. When the first cell module and the second cell module are sequentially arranged in the longitudinal direction of the battery cell, a second tab portion of the second connection tab provided in the first cell module is spaced apart from a first tab portion of the first connection tab provided in the second cell module; 4. The battery pack of claim 3, wherein the second bent portion of the second connection tab of the first cell module is disposed on the first bent portion of the first connection tab of the second cell module.

10. the circuit board unit is disposed on the first cell module and the second cell module such that the connector covers the second bent portion; The battery pack according to claim 9 , wherein the connector is welded to the second bent portion of the first cell module and the first bent portion of the second cell module.

11. 11. The battery pack according to claim 10, wherein the first bent portion of the second cell module, the second bent portion of the first cell module, and the circuit board portion are stacked in a direction different from the longitudinal direction of the battery cells.

12. The battery pack according to claim 10 , wherein the circuit board portion is a flexible circuit board.

13. The battery pack according to claim 10 , wherein the connector is made of a metal material.

14. the first tab portion extends along a radial direction of the battery cell, and the first bent portion extends along a longitudinal direction of the battery cell; The battery pack according to claim 2 , wherein the second tab portion extends along a radial direction of the battery cell, and the second bent portion extends along a longitudinal direction of the battery cell.

15. The first tab portion and the first bent portion are provided so as to be perpendicular to each other, The battery pack according to claim 14 , wherein the second tab portion and the second bent portion are disposed to intersect at right angles.

Images