Battery module and battery pack including the same and manufacturing method of the same

Abstract

A battery module according to one embodiment of the present invention comprises: a battery cell stack in which a plurality of battery cells including electrode leads are stacked; and a Low Voltage (LV) sensing assembly for transmitting voltage information of the battery cells. The LV sensing assembly comprises an LV connector, a connecting member connecting the LV connector and the electrode leads, and a bonding member located at one end of the connecting member and bonded to the electrode leads. At least two of the electrode leads are bent and bonded together to form an electrode lead assembly, and the bonding member is bonded to the electrode lead assembly.

Description

Technology Field

[0001] The present invention relates to a battery module, a battery pack including the same, and a method for manufacturing the same, and more specifically, to a battery module with improved productivity, a battery pack including the same, and a method for manufacturing the same. Background Technology

[0002] In modern society, as the use of portable devices such as mobile phones, laptops, camcorders, and digital cameras has become commonplace, the development of technologies related to such mobile devices is becoming active. Furthermore, rechargeable secondary batteries are being utilized as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) as a solution to address air pollution caused by conventional gasoline vehicles using fossil fuels; consequently, the need for the development of secondary batteries is increasing.

[0003] Currently commercialized rechargeable batteries include nickel-cadmium, nickel-hydrogen, nickel-zinc, and lithium-ion batteries. Among these, lithium-ion batteries are gaining attention for their advantages, such as the ability to charge and discharge freely with almost no memory effect compared to nickel-based batteries, a very low self-discharge rate, and high energy density.

[0004] These lithium secondary batteries primarily use lithium-based oxides and carbon materials as the positive and negative active materials, respectively. The lithium secondary battery comprises an electrode assembly in which a positive plate and a negative plate, each coated with the positive and negative active materials, are arranged with a separator in between, and a battery case that seals and houses the electrode assembly together with an electrolyte.

[0005] Generally, lithium secondary batteries can be classified according to the shape of the casing into can-type secondary batteries, in which the electrode assembly is embedded in a metal can, and pouch-type secondary batteries, in which the electrode assembly is embedded in a pouch of aluminum laminate sheet.

[0006] In the case of secondary batteries used in small devices, 2 to 3 battery cells are arranged, whereas in the case of secondary batteries used in medium to large devices such as automobiles, battery modules in which multiple battery cells are electrically connected are used. In such battery modules, capacity and output are improved by connecting multiple battery cells in series or parallel to form a stack of battery cells. In addition, one or more battery modules can be mounted together with various control and protection systems, such as a Battery Disconnect Unit (BDU), a Battery Management System (BMS), and a cooling system, to form a battery pack.

[0007] FIG. 1 is an exploded perspective view of a conventional battery module.

[0008] Referring to FIG. 1, a conventional battery module (10) is formed by housing a battery cell stack (20) in a module frame (30) and an end plate (40).

[0009] The battery cell stack (20) is formed by stacking a plurality of battery cells along one direction, and accordingly, an electrode lead (21) can protrude in a direction perpendicular to the direction in which the battery cells are stacked.

[0010] The module frame (30) may be made of a material having a certain strength to protect the battery cell stack (20) from external impacts, and structurally, it may be formed by combining an upper frame (31) and a lower frame (32).

[0011] An end plate (40) may be positioned in the protruding direction of the electrode lead (21) relative to the battery cell stack (20), and a busbar frame (50) may be positioned between the battery cell stack (20) and the end plate (40).

[0012] FIG. 2 is an enlarged perspective view showing the busbar frame (50) and end plate (40) included in the battery module of FIG. 1, and FIG. 3 is an enlarged partial view showing part “A” of FIG. 2. At this time, for convenience of explanation, FIG. 3 shows the appearance including the electrode lead (21) of the battery cell.

[0013] Referring to FIGS. 1 to 3, a busbar (51) may be mounted on a busbar frame (50). The busbar (51) is for electrically connecting multiple battery cells, and the electrode lead (21) of the battery cell may pass through a slit formed in the busbar frame (50), bend, and be connected to the busbar (51). Regarding the connection between the electrode lead (21) and the busbar (51), there are no restrictions on the method as long as an electrical connection is possible, and for example, it may be connected by welding. A battery cell stack in which the battery cells are electrically connected through the busbar (51) in this manner may be connected to another battery module or a BDU (Battery Disconnect Unit), etc., through a terminal busbar exposed to the outside. That is, a conventional battery module (10) can electrically connect the battery cells through the busbar (51) and electrically connect the battery module (10) to another battery module through the terminal busbar, etc., thereby enabling a High Voltage (HV) connection. Here, the HV connection refers to a connection that serves as a power source to supply electricity, meaning a connection between battery cells or between battery modules.

[0014] Meanwhile, in order to prevent ignition or explosion of the battery module (10), it is necessary to measure voltage information and temperature information of the battery cells and transmit them to the Battery Management System (BMS). A conventional battery module (10) may include an LV (Low Voltage) sensing assembly (60) to transmit voltage information of the battery cells to the BMS. Specifically, the LV sensing assembly (60) may be connected to a busbar (51) to measure the voltage of each battery cell and transmit the measured value to an external BMS through a connector. That is, the conventional battery module (10) can implement an LV (Low Voltage) connection by transmitting voltage information through the busbar (51) and the LV sensing assembly (60). Here, an LV connection refers to a sensing connection for detecting and controlling the voltage of the battery cells.

[0015] In summary, the conventional battery module (10) can connect the electrode leads (21) of each stacked battery cell to a busbar (51) to implement HV connection, and connect an LV sensing assembly (60) to the busbar (51) to which the electrode leads (21) are connected to implement LV connection. Additionally, a busbar frame (50) can be formed to mount the busbar (51). The problem to be solved

[0016] The problem that the present invention aims to solve is to provide a battery module with improved productivity by improving the conventional HV connection structure and LV connection structure, a battery pack including the same, and a method for manufacturing the same.

[0017] However, the problems that the embodiments of the present invention aim to solve are not limited to the problems described above and can be expanded in various ways within the scope of the technical ideas included in the present invention. means of solving the problem

[0018] A battery module according to one embodiment of the present invention comprises: a battery cell stack in which a plurality of battery cells including electrode leads are stacked; and a Low Voltage (LV) sensing assembly for transmitting voltage information of the battery cells. The LV sensing assembly comprises an LV connector, a connecting member connecting the LV connector and the electrode leads, and a bonding member located at one end of the connecting member and bonded to the electrode leads. At least two of the electrode leads are bent and bonded together to form an electrode lead assembly, and the bonding member is bonded to the electrode lead assembly.

[0019] One surface of the electrode lead assembly may be perpendicular to the direction in which the electrode lead protrudes from the battery cell.

[0020] The above electrode lead may include a positive lead and a negative lead, and based on a single battery cell, the positive lead and the negative lead may protrude in directions facing each other.

[0021] The battery module may include an insulating cover that covers the front and rear surfaces of the battery cell stack in which the electrode leads protrude, and the LV sensing assembly may be mounted on the inner surface of the insulating cover and connected to the electrode leads.

[0022] The inner surface of the insulating cover may face the electrode lead, and an indented mounting portion may be formed on the inner surface of the insulating cover so that the LV sensing assembly can be mounted thereon.

[0023] The insulating cover may include an opening, and the opening may be formed at a position corresponding to the portion where the joining member is joined to the electrode lead.

[0024] The above insulating cover may include a cover portion that covers the opening, and the cover portion may form an opening and closing structure for the opening.

[0025] A battery pack according to one embodiment of the present invention comprises: the battery module; a pack frame housing the battery module; and a thermally conductive resin layer located between the battery module and the bottom portion of the pack frame.

[0026] A method for manufacturing a battery module according to one embodiment of the present invention comprises: a step of forming a battery cell stack by stacking a plurality of battery cells; a step of forming an electrode lead assembly by joining electrode leads protruding from at least two adjacent battery cells among the battery cells; and an LV (Low Voltage) sensing assembly connecting to the electrode lead assembly. The LV sensing assembly includes an LV connector, a connecting member connecting the LV connector and the electrode lead assembly, and a joining member located at one end of the connecting member. The LV connection step includes a step of joining the joining member to the electrode lead assembly.

[0027] The above LV connection step may include the step of mounting the LV sensing assembly on the inner surface of the insulating cover and the step of positioning the insulating cover, on which the LV sensing assembly is mounted, on the front and rear surfaces of the battery cell stack.

[0028] The insulating cover may include an opening, and the LV connection step may further include the step of joining the joining member and the electrode lead assembly through the opening.

[0029] The above insulating cover may include a cover portion that forms an opening and closing structure for the above opening.

[0030] The step of forming the battery cell stack may include the step of applying an adhesive between adjacent battery cells to attach the adjacent battery cells to each other, and the step of bending and joining the electrode leads of each of the adjacent battery cells to each other.

[0031] Prior to the above LV connection step, a step of wrapping the upper surface, lower surface, and both sides of the battery cell stack with a holding band may be performed. Effects of the invention

[0032] According to embodiments of the present invention, instead of a conventional busbar, the connection between electrode leads and the connection between the electrode leads and the LV sensing assembly are integrally formed, so that HV connection and LV connection can be made simultaneously, thus improving productivity can be expected.

[0033] In addition, conventional busbars and busbar frames can be removed, allowing components within the battery module to be arranged more compactly, thereby increasing the capacity or output of the battery module and the battery pack containing it.

[0034] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description in the claims. Brief explanation of the drawing

[0035] FIG. 1 is an exploded perspective view of a conventional battery module. FIG. 2 is an enlarged perspective view showing the busbar frame and end plate included in the battery module of FIG. 1. Figure 3 is a partial view showing an enlarged view of section “A” of Figure 2. FIG. 4 is a perspective view of a battery module according to one embodiment of the present invention. Fig. 5 is an exploded perspective view of the battery module of Fig. 4. FIG. 6 is a perspective view of a battery cell included in the battery module of FIG. 4. FIG. 7 is a perspective view showing the battery module of FIG. 4 with the insulating cover removed. Figure 8 is a partial drawing showing an enlarged view of section “B” of Figure 7. FIGS. 9 to 11 are drawings showing the insulating cover included in the battery module of FIG. 4 from various angles. FIG. 12 is an exploded perspective view of a battery pack according to one embodiment of the present invention. FIGS. 13a to 13c are drawings for explaining a method for manufacturing a battery cell laminate according to an embodiment of the present invention. FIGS. 14a and 14b are drawings for explaining a method of manufacturing a battery module according to one embodiment of the present invention. Specific details for implementing the invention

[0036] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0037] To clearly explain the present invention, parts unrelated to the explanation have been omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0038] Furthermore, the size and thickness of each component shown in the drawings are depicted arbitrarily for convenience of explanation, and thus the present invention is not necessarily limited to what is illustrated. Thicknesses have been enlarged in the drawings to clearly represent various layers and regions. Additionally, for convenience of explanation, the thickness of some layers and regions has been exaggerated in the drawings.

[0039] Furthermore, when a part such as a layer, membrane, region, or plate is said to be "on" or "on" another part, this includes not only the case where it is "directly above" the other part, but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in between. Also, saying that a part is "on" or "on" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "on" or "on" facing the opposite direction of gravity.

[0040] Furthermore, throughout the specification, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0041] Additionally, throughout the specification, "planar" means when the subject part is viewed from above, and "cross-sectional" means when the cross-section obtained by vertically cutting the subject part is viewed from the side.

[0042] FIG. 4 is a perspective view of a battery module according to an embodiment of the present invention. FIG. 5 is an exploded perspective view of the battery module of FIG. 4. FIG. 6 is a perspective view of a battery cell included in the battery module of FIG. 4.

[0043] Referring to FIGS. 4 to 6, a battery module (100) according to one embodiment of the present invention includes a battery cell stack (200) in which a plurality of battery cells (110) are stacked.

[0044] First, the battery cell (110) is preferably a pouch-type battery cell and can be formed into a rectangular sheet-type structure. For example, the battery cell (110) according to the present embodiment has a structure in which two electrode leads (111, 112) protrude from one end (114a) and another end (114b), respectively, facing each other with respect to the cell body (113). More specifically, the electrode leads (111, 112) are connected to an electrode assembly (not shown) and protrude from the electrode assembly (not shown) to the outside of the battery cell (110). One of the two electrode leads (111, 112) may be a positive electrode lead (111) and the other may be a negative electrode lead (112). That is, the positive electrode lead (111) and the negative electrode lead (112) may protrude in directions facing each other with respect to one battery cell (110).

[0045] Meanwhile, the battery cell (110) can be manufactured by bonding the two ends (114a, 114b) of the cell case (114) and the one side (114c) connecting them, while the electrode assembly (not shown) is housed in the cell case (114). In other words, the battery cell (110) according to the present embodiment has a total of three sealing parts, and the sealing parts are sealed by a method such as heat fusion, and the other side can be formed as a connecting part (115). The cell case (114) can be made of a laminate sheet including a resin layer and a metal layer.

[0046] These battery cells (110) may be composed of multiple units, and multiple battery cells (110) may be stacked so as to be electrically connected to each other to form a battery cell stack (200). In particular, as shown in FIG. 5, multiple battery cells (110) may be stacked along the x-axis direction. Accordingly, electrode leads (111, 112) may protrude in the y-axis direction and the -y-axis direction, respectively.

[0047] Meanwhile, unlike the conventional battery module (10) in FIGS. 1 to 3, the battery module (100) according to the present embodiment can form a module-less structure in which the module frame and end plate are removed. Instead of the module frame, the battery module (100) according to the present embodiment may include a side plate (600) and a holding band (700). Since the module frame and end plate are removed, complex processes requiring precise control, such as the process of housing the battery cell stack (200) inside the module frame or the process of assembling the module frame and end plate, are unnecessary. In addition, it has the advantage of significantly reducing the weight of the battery module (100) by the amount of the removed module frame and end plate. Furthermore, the battery module (100) according to the present embodiment has the advantage of being reworkable during the battery pack assembly process due to the removal of the module frame, which can be compared to the conventional battery module (10), in which rework is impossible even if a defect occurs due to the welded structure of the module frame.

[0048] The side plate (600) is a plate-formed member and is positioned on both sides of the battery cell laminate (200) to supplement the rigidity of the battery module (100). This side plate (600) may include a plastic material having elastic properties and manufactured by injection molding, and in some cases, a plate spring material may be applied.

[0049] The holding band (700) is a member that wraps around the battery cell stack at both ends of the battery cell stack (200) and can function to fix the plurality of battery cells (110) constituting the battery cell stack (200) and the side plate (600). In this way, after fixing the battery cell stack (200) and the side plate (600) through the holding band (700), the LV sensing assembly (300) and the insulating cover (400) can be positioned on the front and rear of the battery cell stack (200) corresponding to the direction in which the electrode lead (111) protrudes. This holding band (700) can be made of a material having a certain elastic force, and specifically, a plate spring structure can be applied.

[0050] Hereinafter, with reference to FIGS. 7 to 11, an HV connection structure and an LV connection structure through an LV sensing assembly and an insulating cover according to the present embodiment will be described.

[0051] FIG. 7 is a perspective view showing the battery module of FIG. 4 with the insulating cover removed. FIG. 8 is a partial view showing an enlarged view of section “B” of FIG. 7.

[0052] Referring to FIGS. 5, 7, and 8, the battery module (100) according to the present embodiment includes an LV sensing assembly (300) for transmitting voltage information of a battery cell (110). The LV sensing assembly (300) includes an LV connector (310), a connecting member (320) connecting the LV connector (310) and an electrode lead (111), and a bonding member (330) located at one end of the connecting member (320) and bonded to the electrode lead (111).

[0053] The LV connector (310) may be configured to transmit and receive signals to and from an external control device to control a plurality of battery cells (110). The connecting member (320) may be a flexible printed circuit board (FPCB) or a flexible flat cable (FFC). It can sense the voltage and temperature of the plurality of battery cells (110) and transmit electrical information to a Battery Maintenance System (BMS) through the LV connector (310). That is, the LV sensing assembly (300) including the LV connector (310) and the connecting member (320) can detect and control phenomena such as overvoltage, overcurrent, and overheating of each battery cell (110). The bonding member (330) is located at one end of the connecting member (320) and may be composed of a metal material having electrical conductivity. By joining such a joining member (330) to the electrode lead (111), the connecting member (320) and the electrode lead (111) can be electrically and physically connected. Specifically, one side of the joining member (330) is joined to the connecting member (320) by penetrating the connecting member (320) and then bending, and the other side of the joining member (330) is formed in a plate shape and can be joined to the electrode lead (111), particularly by welding.

[0054] Meanwhile, as described above, the battery cells (110) can be stacked along the x-axis direction to form a battery cell stack (200), and accordingly, the electrode leads (111, 112) can protrude in the y-axis direction and the -y-axis direction, respectively. At this time, as shown in FIG. 8, at least two electrode leads (111) can be bent and joined together to form an electrode lead assembly (111A). Specifically, electrode leads (111) protruding in the same direction relative to adjacent battery cells (110) can be bent in a direction perpendicular to the protrusion direction of the electrode leads (111) and joined together to form an electrode lead assembly (111A). Accordingly, one side of the electrode lead assembly (111A) can be perpendicular to the direction in which the electrode leads (111) protrude from the battery cells (110). Meanwhile, the electrode lead (111) of the battery cell (110) located on the outside of the battery cell stack (200) can be connected to the terminal busbar (500). Unlike conventional battery modules that connect electrode leads to each other through a busbar, the electrode leads (111) according to the present embodiment are directly joined to each other, and some of them are connected to the terminal busbar (500) to form an HV connection. Therefore, in the HV connection structure according to the present embodiment, the busbar and the busbar frame on which the busbar is mounted can be removed.

[0055] Meanwhile, a bonding member (330) of an LV sensing assembly (300) is bonded to such an electrode lead assembly (111A), so that the LV sensing assembly (300) and the electrode lead (111) can be connected to each other. Specifically, the bonding member (330) of the LV sensing assembly (300) can be directly bonded to the surface of such an electrode lead assembly (111A). That is, unlike in conventional battery modules where the LV sensing assembly is mounted on a busbar frame, the LV sensing assembly (300) according to the present embodiment can form an LV connection by being directly connected to the electrode lead assembly (111A) formed by the electrode lead (111).

[0056] Unlike the conventional battery module (10) shown in FIG. 3, where HV connection and LV connection are made separately, the battery module (100) according to the present embodiment can make HV connection and LV connection simultaneously through an electrode lead assembly (111A) and an LV sensing assembly (300) directly connected thereto, and as described above, the configuration of a busbar and a busbar frame is unnecessary. Since HV connection and LV connection can be made at once rather than separately, improved productivity can be expected, and the configuration of a busbar frame can be removed, thereby having the advantage of being able to manufacture a battery module (100) with a more compact configuration.

[0057] Meanwhile, regarding the joining between electrode leads (111) forming the electrode lead assembly (111A) or the joining between the electrode lead assembly (111A) and the joining member (330), there are no special restrictions on the joining method as long as an electrical connection is possible, and for example, welding joining may be performed. In addition, although the description was based on the electrode lead (111) protruding in the y-axis direction, the structure of the electrode lead assembly and the LV sensing assembly (300) can be formed in the same way for the electrode lead (112) protruding in the -y-axis direction.

[0058] Below, with reference to FIGS. 9 to 11, an insulating cover on which an LV sensing assembly is mounted will be described in detail.

[0059] FIGS. 9 to 11 are drawings showing an insulating cover included in the battery module of FIG. 4 from various angles. Specifically, FIG. 9 is an enlarged view of an insulating cover (400) located along the -y-axis direction relative to the battery cell stack (200) in FIG. 4, FIG. 10a and FIG. 10b are enlarged views of an insulating cover (400) located along the y-axis direction relative to the battery cell stack (200) in FIG. 4, and FIG. 11 is a plan view of the insulating cover of FIG. 10a and FIG. 10b viewed in the -y-axis direction on the xz plane.

[0060] First, referring to FIGS. 4 and FIGS. 9, the battery module (100) according to the present embodiment may further include an insulating cover (400) that covers the front and rear surfaces of a battery cell stack (200) having protruding electrode leads (111, 112). The front and rear surfaces of the battery cell stack (200) refer to surfaces corresponding to the y-axis direction and the -y-axis direction, respectively, with respect to the battery cell stack (200). This insulating cover (400) may include a material that exhibits electrical insulation, and may include, for example, a plastic material, a polymer material, or a composite material. Additionally, it may be formed in a basket shape to cover the front and rear surfaces of the battery cell stack (200). In FIGS. 7 and 8, the insulating cover (400) is shown removed for convenience of explanation regarding the LV sensing assembly (300). However, according to the present embodiment, the LV sensing assembly (300) can be connected to the electrode lead (111) while mounted on the inner surface of the insulating cover (400). The inner surface of the insulating cover (400) may refer to the surface of the insulating cover (400) that faces the electrode lead (111), i.e., the electrode lead assembly (111A). Furthermore, an indented mounting portion (410) may be formed on the inner surface of the insulating cover (400) so that the LV sensing assembly (300) can be mounted thereon. Specifically, the mounting portion (410) may be a structure indented in a shape corresponding to the LV sensing assembly (300). Meanwhile, the LV sensing assembly (300) can be fixed to the inner surface of the insulating cover (400), specifically by means such as bolts, heat fusion, bonding, or welding.

[0061] As previously explained, the battery module (100) according to the present embodiment may have the end plate and busbar frame removed, and instead, an insulating cover (400) on which an LV sensing assembly (300) is mounted may be provided. As the insulating cover (400) covers the front and rear of the battery cell stack (200), the LV sensing assembly (300) mounted on the inner side of the insulating cover (400) may be connected to the electrode lead assembly (111A) through a bonding member (330) to form the previously described LV connection structure.

[0062] Next, referring to FIGS. 10a, 10b, and 11, the insulating cover (400) may include an opening (420), and the opening (420) may be formed at a position corresponding to the portion where the bonding member (330) of the LV sensing assembly (300) is bonded to the electrode lead (111). Thus, as in FIG. 11, the bonding member (330) located on the electrode lead assembly can be observed through the opening (420). At this time, for convenience of explanation, the illustration of the cover portion (430), which will be described later, has been omitted in FIG. 11.

[0063] After positioning the insulating cover (400), in which the LV sensing assembly (300) is mounted on the mounting portion (410), on the front and rear of the battery cell stack (200), a bonding member (330) and an electrode lead assembly (111A) can be bonded through the opening (420). For example, a welding device can be inserted through the opening (420) to perform a welded bonding between the bonding member (330) and the electrode lead assembly (111A).

[0064] Additionally, the insulating cover (400) according to the present embodiment may include a cover portion (430) that forms an opening / closing structure for an opening (420). As shown in FIG. 10a, one corner of the cover portion (430) may be connected to the insulating cover (400), and the remaining corners may be separated from the insulating cover (400) to form an opening / closing structure for the opening (420). Accordingly, when joining the joining member (330) and the electrode lead assembly (111A), the cover portion (430) may be opened to form an open state, and in other situations, the cover portion (430) may be closed to maintain a closed state.

[0065] Meanwhile, the insulating cover (400) according to the present embodiment can guide the external connection of the LV connector (310) and the terminal busbar (500) in place of a configuration such as an end plate. Specifically, a connector opening (440) for guiding the external connection of the LV connector (310), i.e., the LV connection, may be formed in the insulating cover (400), and a terminal busbar opening (450) for guiding the external connection of the terminal busbar (500), i.e., the HV connection, may be formed. The insulating cover (400) can block contact with external conductive objects and ensure insulation during the LV connection and HV connection. In addition, during the HV connection process, bolts and nuts may be fastened through a through hole formed in the terminal busbar (500), and the insulating cover (400) and the terminal busbar opening (450) formed therein can function as a guide to ensure that the bolts and nuts are fastened correctly.

[0066] FIG. 12 is an exploded perspective view of a battery pack according to one embodiment of the present invention.

[0067] Referring to FIG. 12, a battery pack (1000) according to one embodiment of the present invention may include a battery module (100), a pack frame (1100) that houses the battery module (100), and a thermally conductive resin layer (1200) located between the battery module (100) and the bottom portion (1111) of the pack frame (1100).

[0068] First, the battery module (100) includes an insulating cover as previously described, and can form a module-less structure in which the module frame and end plate are removed instead. A plurality of such battery modules (100) can be assembled and housed in a pack frame (1100) to form a battery pack (1000).

[0069] The pack frame (1100) may include a lower frame (1110) and an upper frame (1120) covering the lower frame (1110), and a plurality of battery modules (100) may be located on the bottom portion (1111) of the lower frame (1110).

[0070] Meanwhile, the thermally conductive resin layer (1200) may be formed by applying a thermally conductive resin to the bottom portion (1111) of the lower frame (1110). The thermally conductive resin may include a thermally conductive adhesive material, and specifically, may include at least one of silicone, urethane, and acrylic materials. The thermally conductive resin may be in a liquid state when applied, but may harden after application to perform the function of fixing the battery module (100). In addition, it has excellent thermal conductivity characteristics, so it can quickly transfer heat generated from the battery module (100) to the bottom portion (1111) to prevent overheating of the battery pack (1000).

[0071] As illustrated in FIG. 4, the battery module (100) according to the present embodiment has a module-less structure in which the module frame is removed, and a portion of the battery cell (110) may be exposed to the outside. For structural safety, it is essential to fix the exposed battery cell (110). Accordingly, the battery pack (1000) according to the present embodiment aims to improve structural safety by forming a thermally conductive resin layer (1200) on the bottom portion (1111) that can fix the battery module (100), particularly each battery cell (110) constituting the battery module (100).

[0072] Hereinafter, a method for manufacturing a battery module according to an embodiment of the present invention will be described in detail with reference to FIG. 13 and FIG. 14, etc. However, parts that overlap with the previously described parts will be omitted to avoid repetition of the explanation.

[0073] FIGS. 13a to 13c are drawings for explaining a method for manufacturing a battery cell stack according to an embodiment of the present invention. FIGS. 14a and 14b are drawings for explaining a method for manufacturing a battery module according to an embodiment of the present invention.

[0074] First, referring to FIG. 4 and FIG. 13a to FIG. 13c, a method for manufacturing a battery module according to one embodiment of the present invention includes the step of forming a battery cell stack (200) by stacking a plurality of battery cells (110) and the step of forming an electrode lead assembly (111A) by joining electrode leads (111, 112) protruding from at least two adjacent battery cells (110) among the battery cells (110).

[0075] At this time, the step of forming the battery cell stack (200) and the step of forming the electrode lead assembly (111A) can be performed simultaneously. Specifically, when forming the battery cell stack (200) by stacking pouch-type battery cells (110) in which two electrode leads (111, 112) protrude facing each other along one direction, the electrode lead assembly (111A) can be formed by joining the electrode leads (111, 112) of one battery cell (110) with the electrode leads (111, 112) of another battery cell (110), and the method of bending the electrode leads (111, 112) can be performed repeatedly. In addition, an adhesive (800) can be applied between adjacent battery cells to improve the fixing force between adjacent battery cells (110). In other words, the step of forming a battery cell stack (200) according to the present embodiment may include the step of applying an adhesive (800) between adjacent battery cells (110) to attach the adjacent battery cells (110) to each other, and the step of bending and joining the electrode leads (111, 112) of each of the adjacent battery cells (110) to each other.

[0076] Next, referring to FIGS. 4, 9, 10a, 14a, and 14b, the method for manufacturing a battery module (100) according to the present embodiment includes an LV connection step of connecting an LV (Low Voltage) sensing assembly (300) to an electrode lead assembly (111A). The LV sensing assembly (300) includes an LV connector (310), a connecting member (320) connecting the LV connector (310) and the electrode lead assembly (111A), and a bonding member (330) located at one end of the connecting member (320). A detailed description of the above configuration is omitted as it overlaps with the previously described content.

[0077] The above LV connection step includes the step of joining a joining member (330) to an electrode lead assembly (111A). Specifically, the above LV connection step may include the step of mounting an LV sensing assembly (300) on the inner surface of an insulating cover (400) and the step of positioning the insulating cover (400) on which the LV sensing assembly (300) is mounted on the front and rear surfaces of a battery cell stack (200). A mounting portion (410) may be formed on the inner surface of the insulating cover (400) so that the LV sensing assembly (300) can be mounted, and the insulating cover (400) may be positioned so that the inner surface faces the electrode lead assembly (111A). Meanwhile, the insulating cover (400) may be formed in a basket shape and may be coupled to the battery cell stack (200) to cover the front and rear surfaces of the battery cell stack (200).

[0078] At this time, the insulating cover (400) may include an opening (420), and the LV connection step may further include a step of joining the joining member (330) and the electrode lead assembly (111A) through the opening (420). To this end, it is preferable that the opening (420) be formed at a position corresponding to the part where the joining member (330) is joined to the electrode lead (111). Additionally, the insulating cover (400) may further include a cover portion (430) that forms an opening / closing structure for the opening (420). After joining the joining member (330) and the electrode lead assembly (111A), the cover portion (430) can be closed to maintain a closed state.

[0079] Meanwhile, prior to the above LV connection step, a step of placing plate-shaped side plates (600) on both sides of the battery cell stack (200) to supplement the rigidity of the battery module (100) may be performed.

[0080] Additionally, prior to the above LV connection step, a step of wrapping the upper surface, lower surface, and both sides of the battery cell stack (200) with a holding band (700) may be performed. At this time, the holding band (700) may wrap not only the battery cell stack (200) but also the side plates (600) placed on both sides thereof. By fixing the battery cells (110) included in the battery cell stack (200) and the side plates (600) through the holding band (700), the insulating cover (400) can be easily attached to the front and rear of the battery cell stack (200).

[0081] In this embodiment, terms indicating directions such as front, back, left, right, up, and down have been used; however, these terms are for convenience of explanation only and may vary depending on the location of the object or the position of the observer.

[0082] One or more battery modules according to the embodiment described above can be mounted together with various control and protection systems, such as a Battery Management System (BMS) and a cooling system, to form a battery pack.

[0083] The above-mentioned battery module or battery pack can be applied to various devices. Specifically, it can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrids, but is not limited thereto and can be applied to various devices capable of using secondary batteries.

[0084] Although preferred 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 improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention. Explanation of the symbols

[0085] 100: Battery module 111A: Electrode lead assembly 200: Battery cell laminate 300: LV sensing assembly 400: Insulation cover

Claims

Claim 1 A battery module comprising: a battery cell stack having a plurality of battery cells including electrode leads; and an LV (Low Voltage) sensing assembly for transmitting voltage information of the battery cells, wherein the LV sensing assembly includes an LV connector, a connecting member connecting the LV connector and the electrode leads, and a bonding member located at one end of the connecting member and bonded to the electrode leads, wherein at least two of the electrode leads are bent and bonded together to form an electrode lead assembly without the configuration of a busbar and a busbar frame, wherein the bonding member is bonded to the electrode lead assembly, and one surface of the electrode lead assembly is perpendicular to the direction in which the electrode leads protrude from the battery cells, and an adhesive is applied between adjacent battery cells. Claim 2 delete Claim 3 A battery module according to claim 1, wherein the electrode leads include a positive lead and a negative lead, and the positive lead and the negative lead protrude in opposite directions relative to each other based on a single battery cell. Claim 4 In claim 1, the battery module further comprises an insulating cover covering the front and rear surfaces of the battery cell stack having the electrode leads protruding therefrom, and the LV sensing assembly is mounted on the inner surface of the insulating cover and connected to the electrode leads. Claim 5 A battery module according to claim 4, wherein the inner surface of the insulating cover faces the electrode lead, and a recessed mounting portion is formed on the inner surface of the insulating cover so that the LV sensing assembly can be mounted thereon. Claim 6 In paragraph 5, the insulating cover includes an opening, and the opening is formed at a position corresponding to the portion where the joining member is joined to the electrode lead, in a battery module. Claim 7 In claim 6, the insulating cover comprises a cover portion covering the opening, and the cover portion forms an opening and closing structure for the opening, in a battery module. Claim 8 A battery pack comprising: a battery module according to claim 1; a pack frame housing the battery module; and a thermally conductive resin layer located between the battery module and the bottom portion of the pack frame. Claim 9 A step of forming a battery cell stack by stacking a plurality of battery cells; a step of forming an electrode lead assembly by joining electrode leads protruding from at least two adjacent battery cells among the battery cells; A method for manufacturing a battery module, comprising an LV connection step of connecting an LV (Low Voltage) sensing assembly to the electrode lead assembly, wherein the LV sensing assembly comprises an LV connector, a connecting member connecting the LV connector and the electrode lead assembly, and a joining member located at one end of the connecting member, wherein the LV connection step comprises a step of joining the joining member to the electrode lead assembly, wherein in the steps of forming the battery cell stack and forming the electrode lead assembly, the electrode leads of each of the adjacent battery cells are joined and bent together, and an adhesive is applied between the adjacent battery cells, wherein the LV connection step comprises a step of mounting the LV sensing assembly on the inner surface of an insulating cover and a step of positioning the insulating cover on which the LV sensing assembly is mounted on the front and rear surfaces of the battery cell stack, wherein the insulating cover includes an opening, and the LV connection step further comprises a step of joining the joining member and the electrode lead assembly through the opening. Claim 10 delete Claim 11 delete Claim 12 In claim 9, a method for manufacturing a battery module comprising an insulating cover that forms an opening and closing structure for the opening. Claim 13 delete Claim 14 A method for manufacturing a battery module according to claim 9, wherein, prior to the LV connection step, the step of wrapping the upper surface, lower surface, and both sides of the battery cell stack with a holding band is performed.

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