Battery module

Abstract

The present invention relates to a battery module. The battery module according to the present invention includes, as a battery module, a cell stack in which a large number of battery cells are stacked, a module housing that houses the cell stack therein, a module connector that is electrically connected to the cell stack and is provided such that one side portion thereof is exposed to the outside of the module housing and to which an external connector is connected, and a fixing portion that fixes the position of the module connector. The module connector includes a connector portion into which the external connector is inserted and connected, and a connector PCB having a first portion to which the connector portion is fixed and a second portion connected to the first portion. The fixing portion includes a first fixing portion that fixes the first portion and has a locking step into which an end portion of the first portion is inserted to fix the position of the end portion of the first portion, and a second fixing portion that fixes the second portion.

Description

Technical Field

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0064227 filed on May 25, 2022, and Korean Patent Application No. 10-2023-0066811 filed on May 24, 2023, and all the contents disclosed in the documents of the Korean patent applications are incorporated herein by reference in their entirety.

[0002] The present invention relates to a battery module.

Background Art

[0003] Unlike primary batteries, secondary batteries are rechargeable, and due to the possibility of miniaturization and increased capacity, a lot of research and development has been carried out in recent years. With the development of technologies related to mobile devices and the increasing demand, the demand for secondary batteries as an energy source has been rapidly increasing.

[0004] Secondary batteries can be classified into coin-type batteries, cylindrical batteries, prismatic batteries, and pouch-type batteries according to the shape of the battery case. In a secondary battery, the electrode assembly mounted inside the battery case is a power generation element capable of charge and discharge, which consists of a laminated structure of electrodes and separators.

[0005] Secondary batteries have attracted much attention not only as an energy source for mobile devices such as mobile phones, digital cameras, and notebook computers, but also for power devices such as electric bicycles, electric vehicles, and hybrid electric vehicles.

[0006] For small devices such as mobile phones and cameras, small battery packs with a single battery cell packed therein are used, while for medium and large devices such as notebook computers and electric vehicles, medium or large battery packs with two or more battery cells connected in parallel and / or in series are packed. Therefore, the number of battery cells included in the battery pack can be variously set according to the required output voltage or charge and discharge capacity.

[0007] On the other hand, when configuring a battery pack by connecting a plurality of battery cells in series / parallel, it is common to first configure a battery module consisting of at least one battery cell, and then use such at least one battery module to add other components to configure the battery pack.

[0008] That is, a battery is composed of cells, which are the smallest units. Since pouch-shaped cells require structural rigidity, they are composed of intermediate units called modules that contain multiple cells, and packs are composed of multiple modules.

[0009] The module transmits cell information to the pack via a connector, and has a structure in which the connector is exposed from the module for assembly convenience.

[0010] When assembling the connector, if no horizontal force is generated on the insertion part and the force is received in a part of the diagonal direction, the connector is vulnerable to damage, which needs to be structurally improved.

Summary of the Invention

Problems to be Solved by the Invention

[0011] One aspect of the present invention is to provide a battery module capable of stably fixing a module connector in three axial directions.

Means for Solving the Problems

[0012] A battery module according to an embodiment of the present invention is a battery module, including a cell stack in which a large number of battery cells are stacked, a module housing that houses the cell stack therein, and a module connector that is electrically connected to the cell stack and is provided such that one side portion is exposed to the outside of the module housing and to which an external connector is connected, and a fixing portion that fixes the position of the module connector. The module connector includes a connector portion into which the external connector is inserted and connected, and a connector PCB having a first portion to which the connector portion is fixed and a second portion connected to the first portion. The fixing portion can include a first fixing portion that fixes the first portion and has a locking step into which an end portion of the first portion is inserted to fix the position of the end portion of the first portion, and a second fixing portion that fixes the second portion.

Advantages of the Invention

[0013] According to the present invention, the module connector for transmitting information of the battery cell can be fixed in three axial directions by a fixing portion including a first fixing portion and a second fixing portion, and the module connector can be stably fixed.

[0014] In addition, since the first fixing portion includes a pair of locking steps, the module connector can be fixed so as not to be detached in the first direction, and since the second fixing portion includes a coupling protrusion, the module connector can be fixed so as not to be detached in the second and third directions. When an external connector is coupled (assembled) to the module connector, the sway of the module connector can be prevented, and the fixing portion of the module connector can be prevented from being damaged.

Brief Description of the Drawings

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Best Mode for Carrying Out the Invention

[0016] The object, specific advantages, and novel features of the present invention will become more apparent from the following detailed description of the accompanying drawings and the preferred embodiments. In this specification, when attaching reference numerals to the components of each drawing, it should be noted that, as much as possible, the same numbers are used even if they are shown on different drawings for the same components. Further, the present invention can be realized in various different forms and is not limited to the embodiments described here. Also, when explaining the present invention, detailed descriptions of related known technologies that may obscure the gist of the present invention are omitted.

[0017] FIG. 1 is a perspective view showing a battery module according to an embodiment of the present invention, FIG. 2 is a perspective view showing a cell laminate in a battery module according to an embodiment of the present invention, FIG. 3 is an exploded perspective view showing a main part of a battery module according to an embodiment of the present invention, and FIG. 4 is a perspective view showing the state in which a module connector is attached to a battery module according to an embodiment of the present invention.

[0018] Referring to FIGS. 1 to 4, a battery module 100 according to an embodiment of the present invention includes, as the battery module 100, a cell stack 110 in which a large number of battery cells 111 are stacked, a module housing 120 that houses the cell stack 110 therein, a module connector 130 that is electrically connected to the cell stack 110 and is provided such that one side portion thereof is exposed to the outside of the module housing 120 and to which an external connector C is connected, and a fixing portion 140 that fixes the position of the module connector 130. Further, the battery module 100 according to an embodiment of the present invention may further include a pair of bus bar frames 150 and a flexible circuit board 170.

[0019] More specifically, referring to FIG. 2, the cell stack 110 can form a stack in which a large number of battery cells 111 are stacked.

[0020] The battery cell 111 can include an electrode assembly and an electrolytic solution, and a pouch that houses the electrode assembly and the electrolytic solution therein.

[0021] The electrode assembly is a power generation element capable of charge and discharge, and electrodes and separators can be alternately stacked. Here, the electrodes include a positive electrode and a negative electrode, and the positive electrode, separator, and negative electrode can be alternately stacked. Here, the separator separates the positive electrode and the negative electrode and electrically insulates them.

[0022] The positive electrode can include a positive electrode current collector and a positive electrode active material stacked on the positive electrode current collector.

[0023] The positive electrode current collector can be made of a foil of aluminum material.

[0024] The positive electrode active material can be made of lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium iron phosphate, or a compound and mixture containing one or more of these.

[0025] The negative electrode can include a negative electrode current collector and a negative electrode active material stacked on the negative electrode current collector.

[0026] The negative electrode current collector can be made of, for example, a foil made of a copper (Cu) material.

[0027] The negative electrode active material can be a compound or a mixture containing a carbonaceous material.

[0028] The separator is made of an insulating material and electrically insulates between the positive electrode and the negative electrode. Here, the separator 124 can be formed of a polyolefin-based resin film such as polyethylene or polypropylene having microporosity.

[0029] On the other hand, the battery cell 111 can further include an electrode lead 111a having one side connected to the electrode of the electrode assembly and the other side extending outside the pouch.

[0030] The electrode lead 111a can include a positive electrode lead connected to the positive electrode and a negative electrode lead connected to the negative electrode.

[0031] Referring to FIGS. 1 to 3, the module housing 120 can accommodate the cell stack 110 therein.

[0032] The module housing 120 can include a cylindrical case 121 with both sides open and end plates 122 covering the open both sides of the case 121, respectively. Here, one side of the module connector 130 can be exposed outside the end plate 122. A through hole 122a through which one side of the module connector 130 penetrates can be formed in the end plate 122 (see FIG. 5).

[0033] FIG. 5 is a perspective view showing a module connector and an external connector in a battery module according to an embodiment of the present invention.

[0034] Referring to FIGS. 4 and 5, the module connector 130 is electrically connected to the cell stack 110 and is provided such that one side portion is exposed outside the module housing 120, and the external connector C can be connected thereto.

[0035] The module connector 130 can include a connector portion 131 into which the external connector C is inserted and connected, and a connector PCB (printed circuit board) 132 to which the connector portion 131 is fixed.

[0036] The connector portion 131 can include a connection portion 131a into which the external connector C is inserted and connected, and a connection line 131b that electrically connects the connection portion 131a to the connector PCB 132.

[0037] A coupling hole 132a penetrating in the Y-axis direction, which is the first direction, can be formed in the connector PCB 132. Here, a plurality of coupling holes 132a can be provided. Here, the first direction can be a direction perpendicular to the connector PCB 132. That is, the first direction can be a direction perpendicular to the plane of the plate-shaped PCB 132.

[0038] Further, the connector PCB 132 includes a first portion R1 to which the connector portion 131 is fixed and a second portion R2 connected to the first portion R1.

[0039] On the one hand, the external connector C can be composed of a battery pack connector. Also, the information of the battery cell 111 can be transmitted from the module connector 130 to the battery pack via the battery pack connector. Here, the battery pack connector can be connected to the BMS (Battery Management System) of the battery pack. Here, an electrical connection line such as an LV (Low Voltage) line for electrically connecting the battery pack connector and the BMS can be provided. Therefore, information such as the voltage or current of the battery cell 111 can be transmitted from the battery pack connector to the BMS of the battery pack via the module connector 130 electrically connected to the battery cell 111.

[0040] On the other hand, the battery pack can include the battery module 100, the BMS, and a pack case for housing the battery module 100 and the BMS.

[0041] FIG. 6 is a perspective view showing a state before the module connector is mounted in the battery module according to an embodiment of the present invention, FIG. 7 is a perspective view showing a first fixing portion in the battery module according to an embodiment of the present invention, FIG. 8 is a front view showing the module connector and the bus bar frame in the battery module according to an embodiment of the present invention, and FIG. 9 is a front view showing the module connector in the battery module according to an embodiment of the present invention.

[0042] Referring to FIGS. 6 to 9, the fixing portion 140 can fix the position of the module connector 130.

[0043] Also, the fixing portion 140 can include a first fixing portion 141 having a locking step 141a for fixing the first portion R1 of the connector PCB 132 and fixing the position of the end of the first portion R1 by inserting the end of the first portion R1, and a second fixing portion 142 for fixing the second portion R2 of the connector PCB 132.

[0044] The first fixing portion 141 fixes the connector PCB 132 with respect to the first direction (Y-axis) perpendicular to the connector PCB 132, and the second fixing portion 142 is parallel to the connector PCB 132 and can fix the connector PCB 132 with respect to the second direction (X-axis) and the third direction (Z-axis) perpendicular to each other. Here, the end portion of the connector PCB 132 can be provided in a form inserted into the locking step 141a in the second direction so that the end portion of the first portion R1 is prevented from rising with respect to the module housing 120.

[0045] Here, the second direction can be the width direction of the battery module 100, the first direction can be the longitudinal direction of the battery module 100, and the third direction can be the height direction of the battery module 100 (see FIG. 1).

[0046] The first fixing portion 141 fixes the connector PCB 132 with respect to the first direction (the first) perpendicular to the connector PCB 132, and the second fixing portion 142 is parallel to the connector PCB 132 and can fix the connector PCB 132 with respect to the second direction (the second) and the third direction (the third) perpendicular to each other.

[0047] Also, the second fixing portion 142 can include a coupling protrusion 142a that protrudes in the first direction and into which a coupling hole 132a formed in the connector PCB 132 is inserted.

[0048] The coupling protrusion 142a can be formed in a cylindrical or square pillar shape. Here, a plurality of coupling protrusions 142a can be provided.

[0049] On one hand, the coupling protrusion 142a is further formed with an anti - detachment portion 142a - 1 that is wider than the coupling hole 132a at the end, and detachment in the first direction can also be prevented. Here, for example, before the coupling protrusion 142a is inserted into the coupling hole 132a, the coupling protrusion 142a is formed in the shape of a cylinder with a predetermined diameter (see Figure 6). However, after the coupling protrusion 142a is inserted into the coupling hole 132a, by pressing the end of the coupling protrusion 142a, an anti - detachment portion 142a - 1 having a width w1 wider than the width w2 of the coupling hole 132a can be formed (see Figure 4). Here, the coupling protrusion 142a can include, for example, a plastic material.

[0050] The locking steps 141a are provided in a pair and can be bent in an "L" shape in a direction facing each other. Also, the pair of locking steps 141a can be provided at positions contacting both sides of the end of the connector PCB 132 in the first direction.

[0051] Also, the locking step 141a can include a first extension portion 141a - 1 extending in the first direction and a second extension portion 141a - 2 extending in a direction parallel to the third direction from the end of the first extension portion 141a - 1.

[0052] Here, the end of the connector PCB 132 can be intermittently detached in the first direction by the second extension portion 141a - 2 of the locking step 141a.

[0053] On one hand, the width difference L1 between the end of the connector PCB 132 and the end of the connector portion 131 in the Z - axis direction, which is the third direction, can be, for example, 2 - 4 mm. Also, the width difference L2 between the end of the connector PCB 132 and the end of the connector portion 131 in the X - axis direction, which is the second direction, can be, for example, 2 - 4 mm.

[0054] Therefore, the distance between the end of the connector PCB 132 and the end of the connector portion 131 in the second and third directions is formed to be 2 mm or more, which is the lower limit value, and the installation space for the locking step 141a can be ensured.

[0055] Note that the distance between the end of the connector PCB 132 in the second direction and the third direction and the end of the connector part 131 is formed to be 4 mm or less, which is the lower limit value, improving space efficiency, reducing material costs, and enabling the module connector 130 to be easily installed on the end plate 122. Here, when the distance between the end of the connector PCB 132 and the end of the connector part 131 is 4 mm or less, a locking step 141a is installed at a portion where fixing means such as a screw cannot be installed, preventing the end of the connector PCB 132 from lifting up.

[0056] Referring to FIGS. 2 to 4, the bus bar frame 150 is located at both ends of the cell stack 110 and can be connected to the electrode leads 111a of the battery cells 111. Here, the fixing part 140 is formed on the bus bar frame 150, and the module connector 130 can be coupled to the bus bar frame 150.

[0057] Further, the bus bar frame 150 can include a bus bar made of a conductive material that is electrically connected to the electrode leads 111a of the battery cells 111. Here, for example, the connector PCB 132 of the module connector 130 can be soldered to the bus bar of the bus bar frame 150 and electrically connected to the bus bar frame 150.

[0058] The flexible circuit board 170 can be connected to a pair of bus bar frames 150. Here, the flexible circuit board 170 can be electrically connected to the bus bar of the bus bar frame 150, for example.

[0059] Also, the flexible circuit board 170 can be connected to a pair of bus bar frames 150 along the upper surface of the cell stack 110. Here, the flexible circuit board 170 can sense the temperature of the cell stack 110 by including a temperature sensor.

[0060] The battery module 100 according to the embodiment of the present invention configured as described above fixes the module connector 130 that transmits information of the battery cell 111 to the fixing portion 140 including the first fixing portion 141 and the second fixing portion 142 in three axial directions, and can stably fix the module connector 130.

[0061] In addition, since the first fixing portion 141 includes a pair of locking steps 141a, the module connector 130 can be fixed so as not to be detached in the first direction. Since the second fixing portion 142 includes a coupling protrusion 142a, the module connector 130 can be fixed so as not to be detached in the second and third directions. When the external connector C is coupled (assembled) to the module connector 130, the shaking of the module connector 130 can be prevented, and the fixing portion of the module connector 130 can be prevented from being damaged.

[0062] As described above, the present invention has been described in detail with reference to specific embodiments, but this is for specifically explaining the present invention, and the present invention is not limited thereto. It can be said that various implementations are possible by those having ordinary knowledge in the art within the technical idea of the present invention.

[0063] In addition, the specific protection scope of the invention is clarified by the appended claims.

Explanation of Reference Numerals

[0064] 100 Battery module 110 Cell stack 111 Battery cell 111a Electrode lead 120 Module housing 121 Case 122 End plate 130 Module connector 131 Connector portion 132 Connector PCB (Printed circuit board) 132a Coupling hole 140 Fixing portion 141 First fixing portion 141a is a stop section 142 is the second fixing part 142a is a coupling protrusion 150 is a bus bar frame 170 is a flexible circuit board C is an external connector

Claims

1. A battery module, comprising: a cell stack in which a plurality of battery cells are stacked; a module housing that houses the cell stack therein; a module connector that is electrically connected to the cell stack and is provided such that one side portion thereof is exposed outside the module housing, to which an external connector is connected; and a fixing portion that fixes the position of the module connector, wherein the module connector includes: a connector portion into which the external connector is inserted and connected; and a connector PCB having a first portion to which the connector portion is fixed and a second portion connected to the first portion, wherein the fixing portion includes: a first fixing portion that fixes the first portion and has a locking step into which an end portion of the first portion is inserted to fix the position of the end portion of the first portion; and a second fixing portion that fixes the second portion,

2. The first fixing portion fixes the connector PCB with respect to a first direction (Y-axis) perpendicular to the connector PCB, The second fixing portion is parallel to the connector PCB and fixes the connector PCB with respect to a second direction (X-axis) and a third direction (Z-axis) that are perpendicular to each other,

3. The second direction is the width direction of the battery module, the first direction is the longitudinal direction of the battery module, and the third direction is the height direction of the battery module,

4. A coupling hole penetrating in the first direction is formed in the connector PCB, The second fixing portion includes a coupling protrusion that protrudes in the first direction and into which the coupling hole is inserted,

5. The coupling protrusion is formed in a cylindrical or square column shape,

6. A plurality of the coupling holes and the coupling protrusions are provided respectively,

7. The coupling protrusion is further formed with a detachment preventing portion having a width wider than that of the coupling hole at an end portion thereof, also preventing detachment in the first direction,

8. The coupling protrusion includes a plastic material,

9. The battery module according to claim 2, wherein the end of the connector PCB is inserted into the locking step in the second direction so that the end of the first part is prevented from rising with respect to the module housing.

10. The battery module according to claim 9, wherein the locking steps are provided in a pair and are bent in an "L" shape in directions facing each other.

11. The battery module according to claim 10, wherein the pair of locking steps are provided at positions in contact with both sides of the end of the connector PCB in the first direction.

12. The locking step includes a first extension portion extending in the first direction, and a second extension portion extending in a direction parallel to the third direction from the end of the first extension portion, and the end of the connector PCB is interrupted from being separated in the first direction by the second extension portion of the locking step. The battery module according to claim 10.

13. further includes a pair of bus bar frames located at both ends of the cell stack and connected to the electrode leads of the battery cells, wherein the fixing portion is formed on the bus bar frame, and the module connector is coupled to the bus bar frame. The battery module according to claim 1.

14. The external connector consists of a battery pack connector, and the information of the battery cells is transmitted from the module connector to the battery pack through the battery pack connector. The battery module according to claim 13.

15. The module housing includes a cylindrical case with both sides open, and end plates covering both sides of the case respectively, and one side portion of the module connector is exposed outside the end plate. The battery module according to claim 1.

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