Battery module sensing unit and battery module including same

Abstract

A sensing unit for a battery module according to the present invention is for a battery module including a battery pack having a plurality of battery cells, the sensing unit comprising: a bus bar disposed between the battery packs; a sensing member that senses power of the battery cells; and a bonding wire that connects the bus bar and the sensing member, wherein the sensing member comprises: a flexible substrate having flexible characteristics; a line part embedded in the flexible substrate and having a plurality of circuit lines; a terminal part disposed at the end of the circuit lines and exposed on the surface of the flexible substrate; and a pad part disposed on the terminal part, and the pad part comprises: a pad body formed of the same material as the bonding wire; and a coating layer disposed on one side surface of the pad body, wherein the coating layer is surface-mounted on the terminal part.

Description

Battery module sensing unit and battery module including the same

[0001] The present invention relates to a sensing unit for a battery module and a battery module including the same.

[0002] Eco-friendly vehicles like electric vehicles (EVs) are equipped with battery modules that charge the power needed to drive the electric motor. These battery modules are often standardized, aiming to share components to achieve slimmer battery modules and lower costs.

[0003] Standard battery modules require the measurement of the voltage of each battery cell to manage its configuration. For example, each battery cell is welded or clipped with a mechanical or electronic sensor, and components are installed to connect the voltage-measuring sensor to each battery cell. This allows for the measurement of the voltage of each battery cell and the control of each individual cell. If the voltage of each battery cell cannot be measured, control of that cell is impossible, preventing charging and discharging, and ultimately, the cell from functioning as a battery cell.

[0004] In this way, in eco-friendly vehicles, it was necessary to use a sensing unit to sense the voltage of each battery cell to perform functions such as overcharge prevention and voltage balancing.

[0005] The sensing unit may include a rigid printed circuit board, a covered conductive line connected to one side of the printed circuit board, and a busbar connected to the other side of the printed circuit board.

[0006] The covered conductive wire can be formed by covering it with a conductive metal including copper.

[0007] A printed circuit board has multiple circuit lines embedded in it. One end of the circuit line may be connected to a covered conductive wire. The other end of the circuit line may be connected to a busbar.

[0008] For example, the ends of the covered conductive wires connected to one end of each circuit line can be electrically connected by stripping the covering to expose the conductive metal and soldering the exposed conductive metal to a printed circuit board.

[0009] And terminals may be arranged at the other end of each circuit line embedded in the printed circuit board. Pads may be arranged on the terminals. The pads may be connected to bus bars.

[0010] Here, wedge bonding can be performed to connect the pad to the busbar. The bonding wire formed through the wedge bonding process can connect the pad and the busbar. The bonding wire here can be formed of aluminum.

[0011] Conventionally, nickel-bent pads or aluminum-block pads were used to form pads.

[0012] Previously, nickel-plated pads required a bent shape to increase the tensile strength between the printed circuit board surface and the mounting surface. Furthermore, because nickel-plated pads are primarily composed of nickel, their bonding strength is limited compared to aluminum, the bonding wire material.

[0013] In the case of aluminum-block pads, since the material properties of the pad and bonding wire are of the same series, securing bonding tensile strength can be easily achieved. However, since the bonding surface is formed not parallel to the printed circuit board (PCB) surface but intersects it, the fixing or handling of the printed circuit board (PCB) during the wedge bonding process can be difficult.

[0014] Accordingly, there is a need for a pad and a sensing unit including the pad that can improve the tensile strength between the pad and the terminal and the bonding strength between the pad and the busbar while minimizing factors that hinder the design and the process.

[0015] The present invention aims to solve the above-mentioned problems and other problems.

[0016] The present invention aims to provide a sensing unit for a battery module and a battery module including the same, which can reduce defects including cracks caused by vibration and impact that may occur during the process by replacing a printed circuit board with a flexible substrate and eliminating the soldering process.

[0017] And, the present invention aims to provide a sensing unit for a battery module and a battery module including the same, which can improve the bonding tensile strength between a pad portion and a terminal portion and the bonding tensile strength between a pad portion and a busbar by configuring both sides of the pad portion with different materials.

[0018] In addition, the present invention aims to provide a sensing unit for a battery module and a battery module including the same, which improves design ease by forming a mounting surface in the same direction as a flexible substrate surface, thereby facilitating fixation between a pad portion and a terminal portion and bonding between a pad portion and a busbar, and minimizes factors hindering process efficiency.

[0019] According to one aspect of the present invention, a sensing unit for a battery module includes a battery pack having a plurality of battery cells, a busbar arranged between the battery packs, a sensing member for detecting power of the battery cells, and a bonding wire connecting the busbar and the sensing member.

[0020] Here, the sensing member includes a flexible substrate having a ductile characteristic, a line portion embedded in the flexible substrate and having a plurality of circuit lines, a terminal portion positioned at an end of the circuit line and exposed on the surface of the flexible substrate, and a pad portion positioned on the terminal portion.

[0021] The above pad portion includes a pad body formed of the same material as the material of the bonding wire and a coating layer disposed on one side of the pad body, wherein the coating layer is surface-mounted on the terminal portion.

[0022] In addition, the pad body may include a bonding surface formed on a first surface of the pad body and a second surface formed on an opposite surface of the first surface.

[0023] Here, the coating layer includes an adhesive surface that is coated with an alloy containing nickel on the second surface and adhered to the second surface, and a mounting surface that is arranged on the opposite surface to the adhesive surface, and the mounting surface can be mounted on the surface of the terminal portion.

[0024] The shear force formed between the pad portion and the terminal portion may be 20 kgfg or more.

[0025] The above bonding surface can be arranged parallel to the surface of the flexible substrate.

[0026] The above bonding surface and the upper surface of the busbar can be formed to face the same direction.

[0027] The bonding wire may include a first wire connecting the busbar and the battery cell and a second wire connecting the busbar and the sensing member.

[0028] The flexible substrate may include a stem portion formed in a first direction, and a trimming portion extended from one end of the stem portion in a second direction intersecting the first direction.

[0029] The above trimming part may be arranged in the same direction with respect to the listing direction of the busbar and may be arranged adjacent to an end surface of the busbar.

[0030] A bending area is arranged in an area where the trimming portion and the stem portion intersect, and the circuit line can be bent and arranged in the bending area.

[0031] The above trimming section includes a terminal area where the terminal section is arranged and a line area where the circuit line is arranged, and the terminal area may further include a terminal line that extends the circuit line from the line area to the terminal area.

[0032] The above line portion is arranged as an integral part from the stem portion to the terminal portion arranged in the trimming portion, and the formation width of the circuit lines can be adjusted according to each formation length.

[0033] According to one aspect of the present invention, a battery module includes a sensing unit and a module cover accommodating the sensing unit.

[0034] The above module cover includes a receiving area for receiving the battery pack and a border area arranged around the receiving area.

[0035] Here, the border area may include a first border area arranged parallel to the listing direction of the long axis of the busbar, and a second border area arranged parallel to the listing direction of the busbar.

[0036] The above busbar may include a sensing busbar disposed in the receiving area and each disposed between the battery packs, and a frame busbar disposed in the border area and disposed between the border of the module cover and the battery pack.

[0037] The trimming part may be placed in the second border area.

[0038] The effects of the sensing unit for a battery module according to the present invention and the battery module including the same are described as follows.

[0039] According to at least one of the embodiments of the present invention, a sensing unit for a battery module and a battery module including the same can reduce defects including cracks caused by vibration and impact that may occur during a process by replacing a printed circuit board with a flexible substrate.

[0040] According to at least one of the embodiments of the present invention, a sensing unit for a battery module and a battery module including the same can improve the bonding tensile strength between the pad portion and the terminal portion and the bonding tensile strength between the pad portion and the busbar by configuring both sides of the pad portion with different materials.

[0041] According to at least one of the embodiments of the present invention, a sensing unit for a battery module and a battery module including the same can improve design ease by forming a mounting surface in the same direction as a flexible substrate surface to facilitate fixation between a pad portion and a terminal portion and bonding between a pad portion and a busbar, and minimize factors hindering process efficiency.

[0042] Further scope of the applicability of the present invention will become apparent from the detailed description below. However, since various modifications and variations within the spirit and scope of the present invention will become apparent to those skilled in the art, it should be understood that the detailed description and specific examples, such as preferred embodiments of the present invention, are given by way of example only.

[0043] FIG. 1 is a perspective view of a battery module according to one embodiment of the present invention.

[0044] FIG. 2 is a plan view illustrating a sensing member according to one embodiment of the present invention.

[0045] Figure 3 is an enlarged plan view of area A of Figure 2.

[0046] Figure 4 is a cross-sectional view taken along line I-I' of Figure 3.

[0047] Figure 5 is a perspective view of a pad portion according to an embodiment of the present invention.

[0048] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or similar components will be given the same reference numbers, and redundant descriptions thereof will be omitted. The suffixes "module" and "part" used for components in the following description are assigned or used interchangeably only for the convenience of writing the specification, and do not in themselves have distinct meanings or roles. In addition, when describing the embodiments disclosed in this specification, if it is determined that a specific description of a related known technology may obscure the gist of the embodiments disclosed in this specification, a detailed description thereof will be omitted. In addition, the attached drawings are only intended to facilitate easy understanding of the embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the attached drawings, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and technical scope of the present invention.

[0049] Terms that include ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by these terms. These terms are used solely to distinguish one component from another.

[0050] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0051] Singular expressions include plural expressions unless the context clearly indicates otherwise.

[0052] In this application, terms such as “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in the specification, but should be understood not to exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0053] For convenience of explanation, the sizes of components in the drawings may be exaggerated or reduced. For example, the sizes and thicknesses of each component shown in the drawings are arbitrarily indicated for convenience of explanation, and thus the present invention is not necessarily limited to what is shown.

[0054] In some embodiments, where implementations are otherwise feasible, specific process sequences may be performed in a different order than described. For example, two processes described in succession may be performed substantially simultaneously, or in a reverse order from the described order.

[0055] In the following examples, when it is said that a film, region, component, etc. are connected, it includes not only cases where the films, regions, and components are directly connected, but also cases where other films, regions, and components are interposed between the films, regions, and components and thus indirectly connected. For example, when it is said in this specification that a film, region, component, etc. are electrically connected, it includes not only cases where the films, regions, and components are directly electrically connected, but also cases where other films, regions, and components are interposed between them and thus indirectly electrically connected.

[0056] Below, the drawings are provided and explained in detail.

[0057] FIG. 1 is a perspective view of a battery module according to one embodiment of the present invention.

[0058] Referring to FIG. 1, a battery module (10) according to one embodiment of the present invention may include a module cover (15), a battery pack (50), and a sensing unit (100).

[0059] The module cover (15) may be arranged in a container shape. The module cover (15) may form a receiving space due to its container shape. Hereinafter, the area where the receiving space is formed is defined as a receiving area (AR), and the border of the module cover (15) around the receiving area (AR) is defined as a border area (BR). A battery pack (50) may be accommodated in the receiving area (AR).

[0060] The battery pack (50) may include a plurality of battery cells (55). The battery pack (50) may be formed by arranging a plurality of battery cells (55) accommodated in a receiving area (AR) in one direction. For example, the battery pack (50) is described by illustrating a case in which a plurality of battery cells (55) are arranged in a first direction (X), but is not limited thereto. The battery pack (50) may also be arranged in a shape in which the battery cells (55) are stacked according to the shape of the receiving area (AR).

[0061] Additionally, the battery pack (50) may be formed of a single or multiple battery cells (55). And, the battery module (10) may be formed of a single or multiple battery packs (50).

[0062] The battery cell (55) can be charged with power required for operation. The battery cell (55) can include an electrode assembly and a storage unit. The storage unit can store the electrode assembly. In addition, the storage space of the storage unit can contain an electrolyte solution. The storage unit may be in the shape of a pouch, but is not limited thereto. The electrode assembly can include a positive electrode, a negative electrode, and a separator separating them.

[0063] To control the aforementioned battery cell (55) or battery pack (50), the battery module (10) may include a sensing unit (100).

[0064] A sensing unit (100) can be connected to each battery pack (50). The sensing unit (100) can measure the voltage of each battery pack (50) and control each battery cell (55). The sensing unit (100) can include a plurality of busbars (190), sensing members (105), and bonding wires (90) to control each battery cell (55) or each battery pack (50).

[0065] The busbar (190) may be arranged between the battery packs (50) so as to distinguish the battery packs (50) from each other. For example, the busbar (190) may be arranged in a rectangular shape with the long axis formed in the first direction (X) on the receiving area (AR). For a specific example, the battery cells (55) may be arranged in the first direction (X) to form a battery pack (50) in which the first direction (X) is formed as the long axis. In addition, the busbar (190) may be formed with the long axis in the first direction (X) along the shape of the battery pack (50) in which the long axis is formed along the first direction (X).

[0066] And, a plurality of busbars (190) can be arranged along a second direction (Y), which is a direction intersecting the first direction (X), which is the longitudinal direction of the busbar (190). Here, the busbars (190) can be respectively arranged between the battery packs (50).

[0067] The busbar (190) is not limited to a long bar shape as shown in the drawing, and can be formed into any shape that can distinguish the battery packs (50).

[0068] The busbar (190) may include a frame busbar (192) and a sensing busbar (195).

[0069] The frame busbar (192) may be arranged on both sides of the edge of the module cover (15). The frame busbar (192) may be a busbar (190) that covers a battery pack (50) arranged on the edge of the module cover (15). In other words, the frame busbar (192) may be arranged in a border region (BR). Here, for the sake of distinction, the border region (BR) is defined as a region arranged parallel to the long axis of the busbar (190) as a first border region (BR1), and a border region (BR) formed along a direction intersecting the first border region (BR1) as a second border region (BR2). Accordingly, the frame busbar (192) may be arranged on both sides of the first border region (BR1) as an edge of the module cover (15).

[0070] Meanwhile, the busbar (190) may be formed, for example, in a shape formed in a long bar shape on the receiving area (AR). In other words, the busbar (190) may include a major axis surface formed in a first direction (X) in which the battery cells (55) are arranged, and an end surface formed in a second direction intersecting the first direction (X). Here, the busbar (190) may have a busbar upper surface (197) that is connected to the major axis surface and the end surface.

[0071] A plurality of sensing busbars (195) may be arranged between the frame busbars (192). Accordingly, the sensing busbars (195) may be arranged on the receiving area (AR) arranged between the second border areas (BR2). A plurality of sensing busbars (195) may be arranged between the battery packs (50).

[0072] The sensing unit (100) can be connected to a battery pack (50). Specifically, the sensing unit (100) can be connected to a battery cell (55) provided in the battery pack (50) via a bonding wire (90).

[0073] The bonding wire (90) may include a first wire (91) and a second wire (92).

[0074] The first wire (91) may be placed in the receiving area (AR). The first wire (91) may connect the battery cell (55) to the upper surface (197) of the busbar adjacent to the longitudinal axis of the busbar (190). When connecting the busbar (190) to the battery cell (55), the first wires (91) may be placed alternately. For example, the battery cell (55) placed in an even number may be connected to the busbar (190) placed on the left side of the battery cell (55), and the battery cell (55) placed in an odd number may be connected to the busbar (190) placed on the left side of the battery pack (50).

[0075] Meanwhile, the first wire (91) may be placed on a sensing busbar (195) placed in the receiving area (AR), but may also be connected to a frame busbar (192) placed in the border area (BR). In other words, the wire connecting the busbar (190) and the battery cell (55) is defined as the first wire (91).

[0076] In this way, by alternately arranging the first wires (91), space for performing the process can be secured, and thus ease of the process can be secured.

[0077] The second wire (92) may be arranged in the border region (BR). Here, the border region (BR) may include a first border region (BR1) arranged parallel to the longitudinal axis of the busbar (190), i.e., arranged along the first direction (X), as described above, and a second border region (BR2) arranged along the second direction (Y) intersecting the first border region (BR1). Here, the second wire (92) may be arranged to connect between the second border region (BR2) and the receiving region (AR).

[0078] The second wire (92) can connect the sensing member (105) and the busbar (190). The second wire (92) can connect the sensing member (105) to the upper surface (197) of the busbar adjacent to the end of the busbar (190). Specifically, the second wire (92) can connect the surface of the pad portion (150) arranged on the sensing member (105) and the surface adjacent to the end of the busbar (190).

[0079] The surface of the pad portion (150) placed on the sensing member (105) and the upper surface (197) of the busbar adjacent to the end of the busbar (190) can be formed to face the same direction. In other words, the surface of the pad portion (150) can form a surface parallel to the surface of the flexible substrate (110).

[0080] The pad portion (150) can undergo a pretreatment process prior to the bonding process. By controlling the position of the aforementioned plane, the pretreatment process facilitates achieving the optimal thickness and flatness of the pad portion (150). Accordingly, not only can uniform quality be ensured and process errors reduced, but the bonding wire (90) can also achieve optimal tensile strength.

[0081] If the surface of the pad portion (150) and the upper surface of the busbar (197) adjacent to the end of the busbar (190) are designed in different directions, the work efficiency of the bonding process for forming the second wire (92) may be reduced.

[0082] In this way, when the surface of the pad portion (150) and the upper surface of the busbar (197) are formed to face the same direction, the bonding between the sensing member (105) and the busbar (190) can be facilitated, thereby minimizing factors that impede process efficiency.

[0083] The sensing member (105) may be arranged along an area where the ends of the busbars (190) are arranged so as to facilitate connecting a plurality of busbars (190). For example, the sensing member (105) may be arranged along a second direction (Y), which is a direction intersecting the first direction (X) in which the longitudinal axis of the busbars (190) is formed. In other words, the sensing member (105) may be arranged along the second direction (Y) in which the end faces of the busbars (190) are arranged.

[0084] In addition, the sensing unit (100) may further include a connector portion (170). The connector portion (170) may be connected to the sensing member (105). The connector portion (170) may be connected to a control portion (not shown) located in the third direction (Z) by bending the sensing member (105).

[0085] In this way, in another embodiment of the present invention, the battery module (10) is formed so that the surface of the pad portion (150) disposed on the sensing member (105) and the upper surface (197) of the busbar adjacent to the end of the busbar (190) face the same direction, thereby enabling the bonding between the surface of the pad portion (150) of the sensing member (105) and the busbar (190), thereby minimizing factors that hinder process efficiency.

[0086] FIG. 2 is a plan view illustrating a sensing member according to one embodiment of the present invention, and FIG. 3 is an enlarged plan view of area A of FIG. 2.

[0087] As described above, the sensing unit (100) may include a busbar (190), a sensing member (105), and a connector portion (170). One side of the sensing member (105) may be connected to the busbar (190), and the other side of the sensing member (105) may be connected to the connector portion (170).

[0088] Referring to FIGS. 2 and 3, the sensing member (105) may include a flexible substrate (110), a line portion (130), a terminal portion (140), and a pad portion (150).

[0089] The flexible substrate (110) may use a flexible material. For example, the flexible substrate (110) may be composed of a flexible plastic material, and a synthetic resin such as PET (polyethylene terephthalate), PI (polyimide), or PU (polyurethane) that can withstand high temperatures may also be used.

[0090] The flexible substrate (110) can provide flexibility to the sensing member (105) due to the ductile material. The flexibility provided to the sensing member (105) has the effect of eliminating incidental defects that occur during the process.

[0091] For example, in the past, when a sensing element (105) required flexibility, a covered conductive wire was formed by covering it with copper wire or the like, and the flexibility of the covered conductive wire was utilized. In other words, in the past, a soldering process was required to connect the covered conductive wire having flexibility to a rigid printed circuit board.

[0092] Accordingly, a soldering portion is additionally placed between the conductive line and the covered conductive wire of the rigid printed circuit board. The soldering portion may experience poor contact during the manufacturing process, and may experience defects due to vibration or shock when bending to utilize the ductility characteristics.

[0093] However, according to an embodiment of the present invention, the sensing element (105) does not require a soldering process because the line portion (130) including a plurality of circuit lines (135) is embedded in the flexible substrate (110). Therefore, the absence of a soldering portion can fundamentally eliminate secondary defect factors resulting from various process issues, including cracks in the soldering portion.

[0094] The flexible substrate (110) may include a stem portion (113) formed in a first direction (X) and a trimming portion (115) extended in a second direction (Y) from one end of the stem portion (113). Here, the first direction (X) may be the same direction as the longitudinal axis direction of the busbar (190) described above. And, the second direction (Y) may be the same direction as the array direction of the busbar (190). Here, the first direction (X) and the second direction (Y) may be directions intersecting each other. Accordingly, the stem portion (113) and the trimming portion (115) may be arranged in directions intersecting each other.

[0095] The stem portion (113) can be arranged in a direction parallel to the longitudinal direction of the busbar (190). In other words, the stem portion (113) can be arranged in a direction crossing the arrangement direction of the busbar (190).

[0096] The trimming portion (115) may be arranged in the same direction with respect to the arrangement direction of the busbar (190). The trimming portion (115) may include a first trimming portion (115a) and a second trimming portion (115b) which are respectively arranged in the second direction (Y) with respect to the stem portion (113). The first trimming portion (115a) and the second trimming portion (115b) may be arranged in a symmetrical shape or an asymmetrical shape. In the drawing, a shape formed with an asymmetrical length is illustrated as an example.

[0097] The trimming portion (115) may be arranged along the direction in which the ends of the busbar (190) are listed. In other words, the trimming portion (115) may be arranged along the second direction (Y) intersecting the longitudinal direction of the busbar (90). The trimming portion (115) may be arranged adjacent to the end of the busbar (190) so that the sensing member (105) and the busbar (190) can be easily electrically connected.

[0098] A bending area (IB) can be formed in the flexible substrate (110) at the intersection of the trimming portion (115) and the stem portion (113). The bending area (IB) can bend the flexible substrate (110) so that the portion where the connector portion (170), which is the other end of the stem portion (113), is formed can be positioned at a target point.

[0099] The sensing member (105) may include a line portion (130). The line portion (130) may be arranged to be embedded in the flexible substrate (110). The line portion (130) may include a plurality of circuit lines (135). For example, the line portion (130) may be arranged from the first circuit line to the Nth circuit line (131, 132, 133, 134, 135), respectively. Five circuit lines will be illustrated and described in the drawing. In addition, since each of the first circuit line to the Nth circuit lines (131, 132, 133, 134, 135) performs the same role, they will be collectively referred to as a circuit line (135).

[0100] The first circuit line to the Nth circuit lines (131, 132, 133, 134, 135) can adjust the width of the circuit line (135) in consideration of the resistance. For example, in the case of a circuit line (135) that must be formed with a relatively long formation length, the resistance is formed high, so the formation width of the circuit line (135) can be formed wide to reduce the resistance. In the case of a circuit line (135) that must be formed with a relatively short formation length, the resistance can be adjusted by forming the formation width of the circuit line (135) narrow. Therefore, the self-resistance of the circuit line (135) can be formed similarly by adjusting the formation width according to the formation length of the circuit line (135).

[0101] At each end of the circuit lines (135), a first terminal portion (145) and a second terminal portion (not shown) may be arranged. The first terminal portion (145) may be arranged in the trimming portion (115), and the second terminal portion may be arranged at the end of the stem portion (113).

[0102] A connector portion (170) can be connected to the second terminal portion. In other words, the second terminal portion is connected to the connector portion (170) and is covered by the connector portion (170). The number of second terminal portions can be arranged equal to the number of first terminal portions (145).

[0103] The first terminal portion (145) arranged in the trimming portion (115), the second terminal portion arranged in the stem portion (113), and each circuit line (135) arranged between the first terminal portion (145) and the second terminal portion can be formed as an integral part.

[0104] According to an embodiment of the present invention, the line portion (130) is formed to be integrally connected from the stem portion (113) to the trimming portion (115), so that a soldering process for connecting a rigid printed circuit board and a covered conductive wire is not required, thereby increasing the ease of the process.

[0105] The trimming section (115) may include a terminal area (CAA) and a line area (LAA).

[0106] Specifically, the trimming portion (115) may include a terminal area (CAA) where the first terminal portion (145) is arranged. The first trimming portion (115a) and the second trimming portion (115b) arranged in the trimming portion (115) are arranged asymmetrically in length, but are formed symmetrically in terms of structure, and therefore will be described as the trimming portion (115).

[0107] The terminal area (CAA) may further include a terminal line (147) connecting the first terminal portion (145) and the circuit line (135). The terminal line (147) may be bent at a target angle from the circuit line (135) to form a target spacing between the circuit line (135) and the first terminal portion (145). For example, since the spacing between the circuit lines (135) arranged in the line area (LAA) is finely arranged, the terminal line (147) may be a conductive line that leads the circuit line (135) from the line area (LAA) to the terminal area (CAA).

[0108] The terminal line (147) drawn from the line area (LAA) to the terminal area (CAA) can adjust the spacing between the first terminal portions (145) and can also adjust the spacing between the circuit line (135) and the first terminal portion (145). Therefore, by adjusting the spacing, the degree of freedom can be improved due to spatial constraints in the mounting process of the pad portion (150) placed on the first terminal portion (145) or the bonding process connecting the pad portion (150) and the busbar (190).

[0109] If the gap between the circuit line (135) and the first terminal portion (145) is formed as a space that is easy to process, the first terminal portion (145) may be directly connected to the circuit line (135) excluding the terminal line (147).

[0110] The trimming section (115) may include a line area (LAA) in which the circuit lines (135) extending from the second terminal section of the stem section (113) are each branched into a first trimming section (115a) and a second trimming section (115b), and the circuit lines (135) are arranged in the trimming section (115).

[0111] A bending area (IB) may be arranged in the area where the circuit lines (135) each branch off. In the bending area (IB), the circuit lines (135) may each be bent.

[0112] In the bending area (IB), each circuit line (135) may be arranged in a direction different from the first direction (X) and the second direction (Y). Since the bending area (IB) is an area where the flexible substrate (110) is bent, when each circuit line (135) is arranged in the same direction with respect to the first direction (X) and the second direction (Y), the shear force due to the bending of the flexible substrate (110) may be transmitted to each circuit line (135). However, as in the embodiment of the present invention, when the circuit lines (135) are arranged in a bent shape in the bending area (IB), the shear force due to the bending may be minimized, thereby preventing a defect in which the circuit lines (135) are short-circuited.

[0113] Accordingly, the line portion (130) can be arranged to proceed in the first direction (X) from the end of the stem portion (113) to the area before the bending area (IB), and the line portion (130) that is bent in the bending area (IB) and arranged in the trimming portion (115) can be arranged to proceed in the second direction (Y).

[0114] The terminal area (CAA) where the first terminal portion (145) is arranged may be arranged adjacent to the end face of the busbar (190). By arranging the terminal area (CAA) adjacent to the busbar (190), the formation length of the bonding wire (90) can be minimized. For example, by minimizing the formation length of the second wire (92) connecting the busbar (190) and the first terminal portion (145), the probability of defects in the bonding process can be reduced.

[0115] In this way, the sensing member (105) according to the embodiment of the present invention embeds the line portion (130) on the flexible substrate (110), thereby eliminating the soldering process, thereby enhancing reliability against vibration or shock caused by soldering, and improving the efficiency of the process.

[0116] FIG. 4 is a cross-sectional view taken along line I-I' of FIG. 3, and FIG. 5 is a perspective view of a pad portion according to an embodiment of the present invention.

[0117] Before describing the pad portion according to an embodiment of the present invention, in the past, a nickel-bent pad or an aluminum-block pad was used to form the pad.

[0118] For nickel-bent pads, a bent shape may be required to increase the tensile strength between the printed circuit board surface and the mounting surface. For example, nickel-bent pads can increase the tensile strength between the terminal and the pad. However, this increases the cost of the process and components. Furthermore, because nickel-bent pads are primarily composed of nickel, their bonding strength is limited compared to aluminum, the bonding wire material.

[0119] In the case of aluminum block pads, since the material properties of the pad and bonding wire are of the same series, it may be easy to satisfy the requirement for securing bonding tensile strength.

[0120] An aluminum block pad can be formed by plating nickel for the mounting process on the outer surface of a long aluminum bar (AL-Bar), then cutting the aluminum bar to form an aluminum block pad in the shape of a block. Then, a mounting process can be performed on the surface of a printed circuit board (PCB), i.e., on the terminal surface of the printed circuit board, to secure the aluminum block pad to the printed circuit board (PCB).

[0121] Here, the cut surface of the aluminum bar can be the bonding surface, and the surface perpendicular to the bonding surface can be the mounting surface. In other words, the bonding surface may not be formed parallel to the printed circuit board (PCB) surface, but rather in an intersecting direction. This can cause difficulties in fixing or handling the printed circuit board (PCB) during wedge bonding.

[0122] In addition, the aluminum-block pad has a disadvantage in that it is difficult to form a parallel horizontal plane during the mounting process due to its block shape, and there is a problem in that process deviation occurs in the wedge bonding method due to factors such as flatness and roughness depending on the processing condition of the cut surface that becomes the bonding surface.

[0123] In addition, since the bonding surface is formed in a direction that intersects the printed circuit board (PCB) surface, it may be unsuitable for the laser etching process, which is a pretreatment process for securing optimal tensile strength before the wedge bonding process, and thus may be a factor that hinders securing the bonding process quality.

[0124] Referring to FIGS. 4 and 5, a terminal portion (140) may be arranged on a flexible substrate (110), and a pad portion (150) may be arranged on the terminal portion (140). Here, the terminal portion (140) may be arranged on a terminal area (CAA) of the flexible substrate (110). A circuit line (135) may be arranged on a line area (LAA) of the flexible substrate (110). Here, the first terminal portion (145) will be collectively referred to as a terminal portion (140).

[0125] The circuit line (135) arranged on the line area (LAA) may be arranged to be embedded in the flexible substrate (110). The end of the circuit line (135) may further include a terminal line (147) arranged on the terminal area (CAA). The terminal line (147) may be formed integrally with the circuit line (135) and may be arranged on the terminal area (CAA).

[0126] A terminal portion (140) may be arranged at the end of the terminal line (147). The terminal line (147) arranged on the terminal area (CAA) may be arranged to be embedded in the flexible substrate (110) like the circuit line (135). Accordingly, the terminal portion (140) is connected to the circuit line (135), and the terminal line (147) and the circuit line (135) connected to the terminal portion (140) are embedded in the flexible substrate (110) to be protected from the outside and may be insulated from the surrounding conductive material.

[0127] A terminal portion (140) may be arranged at the end of the terminal line (147). The terminal portion (140) may be exposed on the surface of the flexible substrate (110). The terminal portion (140) may be formed to have the same surface level as the surface of the flexible substrate (110), and may be arranged to protrude from the surface of the flexible substrate (110). Alternatively, the terminal portion (140) may be arranged in a shape recessed into the surface of the flexible substrate (110). In the case of a shape recessed into the surface of the flexible substrate (110), the pad portion (150) may be formed in a shape smaller than the shape of the terminal portion (140).

[0128] The terminal portion (140) can be formed to have a wider formation width than the formation width of the circuit line (135).

[0129] A pad portion (150) may be placed on the terminal portion (140) exposed on the surface of the flexible substrate (110).

[0130] The pad portion (150) according to an embodiment of the present invention may include a pad body (151) and a coating layer (158).

[0131] The pad body (151) can be formed of the same material as the bonding wire (90). For example, when the bonding wire (90) includes an aluminum (Al) component, the pad body (151) can be formed of a conductive metal including an aluminum (Al) component.

[0132] In this way, the pad part (150) according to the embodiment of the present invention has a pad body (151) having the same component as the bonding wire (90), so that the bonding tensile strength can be improved.

[0133] The pad body (151) may include a first surface and a second surface disposed on the opposite surface of the first surface. At least one of the first surface and the second surface of the pad body (151) may be a bonding surface (153) on which a bonding wire (90) is disposed. Here, an example in which the first surface is the bonding surface (153) will be described. Accordingly, the pad body (151) may include a bonding surface (153) and a second surface.

[0134] A bonding wire (90) can be bonded to the bonding surface (153). One side of the bonding wire (90) is bonded to the bonding surface (153), and the other side of the bonding wire (90) is bonded to the upper surface (197) of the busbar, so that the pad portion (150) and the busbar (190) can be electrically connected.

[0135] A coating layer (158) may be disposed on the second surface opposite to the bonding surface (153). The coating layer (158) may be formed of a conductive metal including nickel. The coating layer (158) may include an adhesive surface (155) adhered to the second surface, and a mounting surface (159) disposed on the opposite surface of the adhesive surface (155). The coating layer (158) may improve adhesion to the pad body (151) through the adhesive surface (155).

[0136] The coating layer (158) can be formed by coating a conductive metal on the second surface of the pad body (151). Here, the coating layer (158) can be formed as an adhesive surface (155) that adheres to the second surface of the pad body (151) using, for example, a sputtering, evaporator, plating method, etc.

[0137] A mounting surface (159) formed on the opposite side of the adhesive surface (155) may be disposed on the coating layer (158). The mounting surface (159) may be surface-mounted on the terminal portion (140). Here, a soldering material (not shown) may be disposed between the mounting surface (159) and the terminal portion (140).

[0138] The mounting surface (159) of the coating layer (158) can improve the adhesive strength with the terminal portion (140). For example, when the adhesive surface (155) of the pad body (151) and the terminal portion (140) are mounted, lead can be used by soldering between the adhesive surface (155) of the pad body (151) made of aluminum and the terminal portion (140). Since lead has low reactivity with aluminum, the adhesive strength between the adhesive surface (155) of the pad body (151) and the terminal portion (140) can be reduced. On the other hand, as in the embodiment of the present invention, when the coating layer (158) is disposed between the adhesive surface (155) of the pad body (151) and the terminal portion (140), the adhesive strength between the terminal portion (140) and the pad portion (150) can be improved because lead and nickel have excellent reactivity.

[0139] The coating layer (158) can improve the adhesive strength between the coating layer (158) and the pad body (151) through the adhesive surface (155). In addition, the mounting surface (159) of the coating layer (158) can improve the adhesive strength between the terminal portion (140) and the pad portion (150), thereby improving the bonding strength.

[0140] Therefore, the coating layer (158) according to the embodiment of the present invention can stabilize the adhesion between the pad portion (150) and the terminal portion (140). Furthermore, as the adhesion between the pad portion (150) and the terminal portion is stabilized, the bonding between the bonding wires (90) can be stabilized.

[0141] Table 1 shows the results of measuring the shear force between the pad portion (150) and the terminal portion (140).

[0142] A peel tester was used to measure shear force. The peel tester measured the peel force of the adhesive sample as the adhesive force per unit length. For example, a 5 kgf load was applied to the pad to determine whether the pad detached.

[0143] The shear force was measured for five pad sections (150) placed in the first trimming section (155a). Here, the measurement was performed with the goal of having a shear strength of 5 Kfg or more.

[0144] Sample 1 is the pad part (150) positioned closest to the stem part (113), and sample 5 is the pad part (150) positioned furthest from the stem part (113). The samples between sample 1 and sample 5 are pad parts (150) positioned between sample 1 and sample 5.

[0145] SampleSample 1Sample 2Sample 3Sample 4Sample 5Shear strength (Kfg)27.4131.2527.7730.4727.80

[0146] According to Table 1, the shear strength between the pad portion (150) and the terminal portion (140) was measured to be 20 Kgf or more in both cases. Therefore, the pad portion (150) according to the embodiment of the present invention was measured to have a shear strength of 5 Kgf or more, which is the target value.

[0147] Any or all of the embodiments of the present invention described above are not mutually exclusive or distinct. Any or all of the embodiments of the present invention described above may have their respective components or functions combined or used together.

[0148] It will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit and essential characteristics thereof. The above detailed description should not be construed in any way as limiting but rather as illustrative. The scope of the present invention should be determined by a reasonable interpretation of the appended claims, and all modifications within the scope of equivalents of the present invention are intended to be included within the scope of the present invention.

[0149] [Explanation of symbols]

[0150] 10: Battery module 15: Module cover

[0151] 50: Battery pack 55: Battery cell

[0152] 90: Bonding wire 91: First wire

[0153] 92: Second wire 100: Sensing unit

[0154] 105: Sensing member 110: Flexible substrate

[0155] 113: Stem 115: Trimming

[0156] 130: Line section 135: Circuit line

[0157] 140: Terminal section 147: Terminal line

[0158] 150: Pad part 151: Pad body

[0159] 153: Bonding surface 155: Adhesive surface

[0160] 158: Coating layer 159: Mounting surface

[0161] 170: Connector section 190: Busbar

[0162] 192: Frame busbar 195: Sensing busbar

[0163] 197: Busbar top surface AR: Receptive area

[0164] BR: Border area X: First direction

[0165] Y: Second direction IB: Bending area

[0166] CAA: Terminal area LAA: Line area

Claims

1. A battery module including a battery pack having a plurality of battery cells, A busbar arranged between the above battery packs; A sensing member for detecting the power of the battery cell; and A bonding wire connecting the above busbar and the above sensing member; including: The above sensing member, Flexible substrate having ductile properties; A line section embedded in the above flexible substrate and having a plurality of circuit lines; A terminal portion positioned at the end of the circuit line and exposed on the surface of the flexible substrate; and A pad portion disposed on the terminal portion; including; The above pad part, A pad body formed of the same material as the material of the above bonding wire; and A coating layer disposed on one side of the above pad body; Including, A sensing unit for a battery module, wherein the coating layer is surface-mounted on the terminal portion.

2. In paragraph 1, The above pad body, A bonding surface formed on the first surface of the above pad body; and A second surface formed on the opposite side of the first surface; including; The above coating layer is, An adhesive surface that is coated with an alloy containing nickel on the second surface and adheres to the second surface; and Including a mounting surface arranged on the opposite side to the above adhesive surface; The above-mentioned mounting surface is a sensing unit for a battery module, which is mounted on the surface of the terminal portion.

3. In paragraph 1, A sensing unit for a battery module, wherein a shear force formed between the pad portion and the terminal portion is 20 kgfg or more.

4. In paragraph 2, A sensing unit for a battery module, wherein the bonding surface is arranged parallel to the surface of the flexible substrate.

5. In paragraph 2, A sensing unit for a battery module, wherein the bonding surface and the upper surface of the busbar are formed to face the same direction.

6. In paragraph 1, The above bonding wire, A first wire connecting the above busbar and the above battery cell; and A sensing unit for a battery module, comprising: a second wire connecting the busbar and the sensing member; 7. In paragraph 1, The above flexible substrate, Stem formed in the first direction; A sensing unit for a battery module, comprising a trimming portion extending in a second direction intersecting the first direction from one end of the stem portion.

8. In paragraph 7, The above trimming part, The above busbars are arranged in the same direction as the listing direction, A sensing unit for a battery module, arranged adjacent to an end face of the above busbar.

9. In paragraph 7, A bending area is arranged in the area where the above trimming portion and the above stem portion intersect, A sensing unit for a battery module, in which the circuit line is arranged in a bent state in the above bending area.

10. In paragraph 7, The above trimming part, A terminal area where the terminal portion is arranged; and Including a line area where the above circuit line is arranged, In the above terminal area, A sensing unit for a battery module, further comprising a terminal line for leading the circuit line from the line area to the terminal area.

11. In paragraph 7, The above line section, A sensing unit for a battery module, wherein the circuit lines are arranged in an integrated manner from the stem portion to the terminal portion arranged in the trimming portion, and the formation width of each circuit line is adjusted according to the formation length.

12. A sensing unit comprising any one of claims 1 to 11; and A battery module comprising a module cover accommodating the sensing unit; 13. In paragraph 12, The above module cover, a receiving area for accommodating the battery pack; and A border area arranged around the periphery of the above-mentioned receiving area; including; The above border area is, A first border area arranged parallel to the listing direction of the longitudinal axis of the above busbar, A battery module comprising a second border region arranged parallel to the listing direction of the above busbars.

14. In paragraph 13, The above busbar, A sensing busbar arranged in the above-mentioned receiving area and each arranged between the battery packs; and A battery module, comprising: a frame busbar arranged in the above-mentioned border area and arranged between the border of the module cover and the battery pack; 15. In paragraph 13, A battery module, wherein the trimming part is arranged in the second border area.

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