Busbar assembly and battery pack including same

Abstract

A busbar assembly according to an embodiment of the present invention includes: a first busbar and a second busbar which are arranged in parallel with each other, wherein each of the first busbar and the second busbar includes a body portion, and an end portion extending from either end of the body portion and having a through-hole defined therein; a first insulating layer surrounding the body portion of the first busbar; a second insulating layer surrounding the body portion of the second busbar; and a cap simultaneously surrounding the end portion of the first busbar and the end portion of the second busbar, which are adjacent to each other.

Description

Busbar assembly and battery pack including the same

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0103595, filed August 8, 2023, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a busbar assembly and a battery pack including the same, and more particularly, to a busbar assembly with improved insulation stability and a battery pack including the same.

[0004] In modern society, the widespread use of portable devices like cell phones, laptops, camcorders, and digital cameras has fueled active development of technologies related to these devices. Furthermore, rechargeable secondary batteries are increasingly being used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) to address air pollution caused by conventional gasoline-powered vehicles, further fueling the growing need for secondary battery development.

[0005] Currently commercialized secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries are receiving attention for their advantages of being able to charge and discharge freely, having a very low self-discharge rate, and having a high energy density, as they have almost no memory effect compared to nickel-based secondary batteries.

[0006] These lithium secondary batteries primarily use lithium oxide and carbon materials as the positive and negative electrode active materials, respectively. The lithium secondary battery comprises an electrode assembly comprising a positive electrode plate and a negative electrode plate, each coated with the positive and negative electrode active materials, with a separator interposed between them, and a battery case that seals and houses the electrode assembly together with an electrolyte.

[0007] In general, lithium secondary batteries can be classified into can-type secondary batteries in which the electrode assembly is built into a metal can and pouch-type secondary batteries in which the electrode assembly is built into a pouch of an aluminum laminate sheet, depending on the shape of the outer packaging material.

[0008] Secondary batteries used in small devices are configured with two to three battery cells, but secondary batteries used in medium to large devices such as automobiles utilize battery modules in which multiple battery cells are electrically connected. These battery modules enhance capacity and output by forming a battery cell stack by connecting multiple battery cells in series or parallel. In addition, one or more battery modules may 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.

[0009] Battery packs comprised of multiple battery modules can experience rapid and severe temperature increases due to the accumulation of heat from the numerous battery cells within a confined space. In other words, while battery modules stacked with multiple battery cells and battery packs equipped with these modules can achieve high output, if the heat dissipation between the cells is inadequate or if thermal runaway occurs, there is a high risk of continual fires or subsequent explosions.

[0010] Meanwhile, inside the battery pack, a bus bar is provided that connects to the battery module.

[0011] Figure 1 is an exploded perspective view and a combined perspective view of a conventional busbar assembly.

[0012] Referring to Fig. 1, a conventional busbar assembly (10) includes a busbar (20), a covering (20C) covering the busbar (20), a cap (CP), and a tape (AL) for fixing the cap (CP). The busbar (20) is a metal member in the shape of a rod extending along the longitudinal direction. Through holes (HH) for connection with terminal busbars of a battery module may be formed at both ends of the busbar (20). This busbar (20) is a component that is responsible for HV (High voltage) connection in a battery pack. The HV connection refers to a connection that serves as a power source for supplying electric power, and the busbar (20) is a component that guides the electrical connection of the battery module, and generally includes a metal material with excellent electrical conductivity. For example, the busbar (20) may include a copper (Cu) material.

[0013] The covering (20C) can wrap around the bus bar (20). The covering (20C) can include an electrically insulating material, for example, a material such as silicone or epoxy. Since the covering (20C) wraps around the bus bar (20) through which a high current flows, the bus bar (20) is prevented from coming into contact with other electrical components or conductive members other than the terminal bus bar of the battery module, thereby preventing a short circuit from occurring.

[0014] A fastening member is inserted into the through hole (HH) of the bus bar (20) to connect the bus bar (20) to the terminal bus bar of the battery module. For insulation, a cap (CP) is attached to both ends of the bus bar (20). The cap (CP) may be, for example, a rubber cap. The cap (CP) may be attached to the covering (20C) using a tape (AL).

[0015] However, when a flame occurs inside the battery pack, the temperature of the flame is very high, approximately 1000°C, so the covering (20C) surrounding the bus bar (20) may melt, or the cap (CP) and tape (AL) may melt, exposing the bus bar (20). If the exposed bus bar (20) comes into contact with another conductive member and a short circuit occurs, the internal flame may spread further and may even spread to the outside of the battery pack. Ultimately, this may lead to an explosion of the battery pack or a vehicle equipped with the battery pack.

[0016] Accordingly, there is a need for technology development for a busbar assembly that can maintain electrical insulation even when a flame occurs inside a battery pack.

[0017] The problem to be solved by the present invention is to provide a busbar assembly that can maintain electrical insulation without melting even when a flame occurs inside a battery pack, and a battery pack including the same.

[0018] However, the problems to be solved by the embodiments of the present invention 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.

[0019] The busbar assembly of the present invention comprises: a first busbar and a second busbar arranged in parallel with each other; each of the first busbar and the second busbar including a body portion and an end portion extending from both ends of the body portion and having a through hole defined therein; a first insulating layer surrounding an outer circumferential surface of the first busbar; a second insulating layer surrounding an outer circumferential surface of the second busbar; and a cap simultaneously surrounding the end portion of the first busbar and the end portion of the second busbar that are adjacent to each other.

[0020] In one embodiment, the cap may include a baffle disposed between the end of the first bus bar and the end of the second bus bar.

[0021] In one embodiment, the cap includes a first space and a second space separated by the bulkhead, and the end of the first bus bar can be disposed in the first space, and the end of the second bus bar can be disposed in the second space.

[0022] In one embodiment, the caps are provided in plurality at both ends of the first bus bar and the second bus bar, and the partition walls included in the plurality of caps can be connected to each other by extending in the longitudinal direction of the first bus bar.

[0023] In one embodiment, the bulkhead may extend in the thickness direction of the first bus bar, such that an end thereof may protrude below the end of the first bus bar and the end of the second bus bar.

[0024] In one embodiment, the cap further includes a protrusion protruding left and right from the bulkhead, and an upper surface of the protrusion can contact a lower surface of the end of the first bus bar and a lower surface of the end of the second bus bar.

[0025] In one embodiment, each of the first insulating layer and the second insulating layer may have a groove formed in a sunken shape, and the cap may include a fastening portion inserted into the groove.

[0026] In one embodiment, each of the first insulating layer and the second insulating layer may include a first portion surrounding the body portion and a second portion extending from the first portion, surrounding a portion of the end portion, and covered by the cap.

[0027] In one embodiment, two grooves may be provided on the upper surface of the first portion and formed adjacent to the second portion.

[0028] In one embodiment, the groove may be formed along the perimeter of the second portion.

[0029] In one embodiment, the first insulating layer and the second insulating layer may be more elastic than the cap.

[0030] In one embodiment, the device may further include a glass fiber layer surrounding the first insulating layer and the second insulating layer.

[0031] In one embodiment, the first insulating layer and the second insulating layer may comprise refractory silicone.

[0032] In one embodiment, the cap may comprise any one of a refractory plastic, mica, or refractory silicone.

[0033] The battery pack of the present invention comprises at least one busbar assembly; battery modules; a BDU (battery disconnect unit) module for controlling electrical connection of the battery modules; and a BMS (battery management system) module for monitoring and controlling operation of the battery modules, wherein the at least one busbar assembly electrically connects at least one of the battery modules, the battery module and the BDU module, the battery module and the BMS module, and the BDU module and the BMS module.

[0034] The busbar assembly of the present invention can improve insulation and fire resistance by allowing the busbar covering and cap to maintain their shape even when exposed to flame.

[0035] The effects of the present invention are not limited to the effects described above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0036] Figure 1 is an exploded perspective view and a combined perspective view of a conventional busbar assembly.

[0037] Figure 2 is a plan view of a battery pack of one embodiment.

[0038] FIG. 3 is a perspective view of one of the battery modules included in the battery pack of FIG. 2.

[0039] Figure 4 is a partial perspective view showing the battery module of Figure 3 with the module frame and end plate removed.

[0040] Figure 5 is a perspective view of a bus bar of one embodiment.

[0041] Fig. 6 is a plan view of a busbar provided with an insulating layer according to one embodiment.

[0042] Figure 7 is a plan view of a busbar assembly of one embodiment.

[0043] Figure 8 is a side view of a busbar assembly of one embodiment.

[0044] Figure 9 is a cross-sectional view of a busbar assembly of one embodiment.

[0045] Figure 10 is a cross-sectional view of a busbar assembly of one embodiment.

[0046] Fig. 11 is a cross-sectional view of a busbar assembly of one embodiment.

[0047] Figure 12 is a plan view of a busbar assembly of one embodiment.

[0048] Figure 13 is a plan view of a busbar assembly of one embodiment.

[0049] Figure 14 is a plan view of a busbar assembly of one embodiment.

[0050] Fig. 15 is a plan view of a busbar provided with an insulating layer according to one embodiment.

[0051] Figure 16 is a plan view of a busbar assembly of one embodiment.

[0052] Figure 17 is a side view of a busbar assembly of one embodiment.

[0053] Fig. 18 is a cross-sectional view of a busbar assembly of one embodiment.

[0054] Figure 19 is a cross-sectional view of a busbar assembly of one embodiment.

[0055] Figure 20 is a rear view of a busbar assembly of one embodiment.

[0056] Figure 21 is a cross-sectional view of a busbar assembly of one embodiment.

[0057] Figure 22 is a rear view of a busbar assembly of one embodiment.

[0058] 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 invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0059] In order to clearly explain the present invention, parts that are not related to the description are omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0060] Furthermore, 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 the illustrated components. In the drawings, the thicknesses are enlarged to clearly represent various layers and regions. Furthermore, in the drawings, the thicknesses of some layers and regions are exaggerated for convenience of explanation.

[0061] Furthermore, when we say that a layer, membrane, region, plate, or other part is "on" or "over" another part, this includes not only cases where it is "directly on" the other part, but also cases where there are other parts in between. When we say that a part is "directly on" another part, we mean that there are no other parts in between. Furthermore, when we say that a part is "on" or "over" a reference part, we mean that it is located above or below the reference part, and we do not necessarily mean that it is located "above" or "over" the reference part in the opposite direction of gravity.

[0062] Additionally, throughout the specification, whenever a part is said to “include” a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0063] Additionally, throughout the specification, when we say "in plan", we mean when the target portion is viewed from above, and when we say "in cross section", we mean when the target portion is viewed from the side in a cross-section cut vertically.

[0064] Additionally, throughout the specification, the first direction (DR1), the second direction (DR2), and the third direction (DR3) are used as relative concepts. The first direction (DR1), the second direction (DR2), and the third direction (DR3) may be perpendicular to each other. Throughout the specification, the concept of up and down is explained as being distinguished along the third direction (DR3). Specifically, the upward or upper direction refers to the third direction (DR3). The downward or lower direction refers to the direction opposite to the third direction (DR3). The term “thickness” in the specification refers to the length measured in the third direction (DR3).

[0065] Figure 2 is a plan view of a battery pack of one embodiment.

[0066] Referring to FIG. 2, a battery pack (1000) according to one embodiment includes a busbar assembly (100), a pack frame (1100), battery modules (1200), a BDU (battery disconnect unit) module (1300) for controlling electrical connection of the battery modules (1200), and a BMS (battery management system) module (1400) for monitoring and controlling operation of the battery modules (1200). At least one busbar assembly (100) according to the present embodiment electrically connects at least one of the battery modules (1200), between the battery modules (1200) and the BDU module (1300), between the battery modules (1200) and the BMS module (1400), and between the BDU module (1300) and the BMS module (1400). Specifically, a plurality of battery modules (1200) can be housed in a pack frame (1100), and electrical connections between the battery modules (1200) or electrical connections between the battery modules (1200) and the BDU module (1300) can be made by the busbar assembly (100). That is, the busbar assembly (100) according to the present embodiment can be responsible for HV (High voltage) connections. Here, the HV connection is a connection that serves as a power source for supplying power requiring high voltage, and means a connection between battery cells or a connection between battery modules.

[0067] Meanwhile, the BDU module (1300) is a member for controlling the electrical connection of the battery module (1200) and can cut off power between the power conversion device and the battery module (1200). The BDU module (1300) can cut off power to the battery pack (1000) when a condition occurs in which the current exceeds a set range, thereby ensuring the safety of the battery pack (1000).

[0068] Meanwhile, the LV connecting member (100') according to the present embodiment can be responsible for the electrical connection between the battery module (1200) and the BMS module (1400). The electrical connection here is a LV (Low voltage) connection, which means a sensing connection for detecting and controlling the voltage and temperature of the battery module (1200). Specifically, sensors, etc. are arranged inside the battery module (1200), and real-time temperature information or voltage information of the battery module (1200) is transmitted to the BMS module (1400) through the LV connecting member (100'). The real-time operating status of the battery module (1200) can be monitored and controlled through the BMS module (1400). Although not specifically illustrated, there are cases where an HV current sensor is integrated into the BMS module (1400). In this case, the busbar assembly according to the present embodiment may be responsible for electrical connection between the battery module (1200) and the BMS module (1400) or between the BDU module (1300) and the BMS module (1400).

[0069] Referring to FIGS. 3 and 4, a battery module (1200) according to the present embodiment will be described. However, the battery module (1200) described below is an exemplary structure of a battery module including a plurality of battery cells (11), and various types of battery modules including a plurality of battery cells may be applied.

[0070] FIG. 3 is a perspective view showing one of the battery modules included in the battery pack of FIG. 2.

[0071] Figure 4 is a partial perspective view showing the battery module of Figure 3 with the module frame and end plate removed.

[0072] Referring to FIGS. 3 and 4, the battery module (1200) according to the present embodiment may include a battery cell stack (11A) in which a plurality of battery cells (11) are stacked. The battery cell stack (11A) is illustrated in FIG. 4. This battery cell stack (11A) may be accommodated in a module frame (30) and an end plate (40).

[0073] The battery cell (11) may be a pouch-type battery cell. Such a pouch-type battery cell may be formed by housing an electrode assembly in a pouch case made of a laminate sheet including a resin layer and a metal layer, and then fusing the outer periphery of the pouch case. Such a battery cell (11) may be formed in a rectangular sheet structure. An electrode lead (11L) connected to the electrode assembly protrudes to the outside of the pouch case, and the electrode leads (11L) of each battery cell (11) may be electrically connected to each other via a lead bus bar (21). Meanwhile, at least one electrode lead (11L) may be connected to a terminal bus bar (22). A portion of the terminal bus bar (22) may be exposed to the outside of the battery module (1200), as illustrated in FIG. 3. Both the lead bus bar (21) and the terminal bus bar (22) may include a metal material having excellent electrical conductivity.

[0074] The busbar assembly (100) according to the present embodiment is electrically connected to the terminal busbar (22), so that the above-described HV connection can be made. That is, the battery module (1200) can be electrically connected to another battery module (1200), BDU module (1300), or BMS module (1400) via the busbar assembly (100) connected to the terminal busbar (22).

[0075]

[0076] Below, a busbar assembly according to one embodiment is described.

[0077] Figure 5 is a perspective view of a bus bar of one embodiment.

[0078] Referring to FIG. 5, a busbar (200) guides electrical connections within a battery pack (1000, see FIG. 2). The busbar (200) is configured to guide electrical connections, i.e., HV connections, of a battery module (1200, see FIG. 2), and may include a metal material with excellent electrical conductivity. For example, the busbar (200) may include a copper (Cu) material. The body portion (210) may have a rod shape extending in one direction. In FIG. 2, as an example, the busbar (200) is illustrated as having a rod shape extending in a first direction (DR1).

[0079] A bus bar (200) of one embodiment includes a body portion (210) and an end portion (220). The body portion (210) may correspond to the center of the bus bar (200). The end portions (220) extend from both ends of the body portion (210). For example, the end portions (220) may extend from both ends of the body portion (210) in a first direction (DR1) and a direction opposite to the first direction (DR1). In the present specification, for convenience, the bus bar (200) is described as including the body portion (210) and the end portions (220), but the body portion (210) and the end portions (220) have an integral shape.

[0080] A through hole (HH) is defined in the end portion (220). A fastening member is inserted into the through hole (HH) to connect the bus bar (200) to an external electrical device. For example, a bolt may be inserted into the through hole (HH) of the end portion (220) to connect the bus bar (200) and the terminal bus bar (22, see FIG. 3) of the battery module (1200, see FIG. 3).

[0081] Figure 6 is a perspective view of a busbar provided with an insulating layer according to one embodiment.

[0082] Referring to Fig. 6, an insulating layer (300) is provided to surround a body portion (210, see Fig. 5) of a bus bar (200). That is, the insulating layer (300) is provided to insulate the body portion (210, see Fig. 5). At this time, at least a portion of the end portion (220) is exposed from the insulating layer (300) and can be electrically connected to a terminal bus bar (22, see Fig. 3) of a battery module (1200, see Fig. 3).

[0083] The insulating layer (300) may include a first portion (310) that surrounds the body portion (210, see FIG. 5) of the bus bar (200) and a second portion (320) that surrounds a portion of the end portion (220). The first portion (310) may surround the outer circumference of the body portion (210) of the bus bar (200). The second portion (320) is a portion that extends from both ends of the first portion (310) and is covered by a cap (400) described later. The second portion (320) extends in opposite directions from both ends of the first portion (310). Specifically, the second portion (320) is provided to extend in the first direction (DR1) from one end of the first portion (310) and in the opposite direction of the first direction (DR1) from the other end of the first portion (310). By covering a portion of the end (220) with the second portion (320) of the insulating layer (300), the bus bar (200) can be prevented from being exposed between the insulating layer (300) and the cap (400) described below. In addition, the insulating layer (300) can secure an insulating distance of the bus bar (200) by including the second portion (320).

[0084] Meanwhile, a groove (GV) having a sunken shape is formed in the insulating layer (300). In one embodiment, the groove (GV) may be formed on the upper surface of the first portion (310) and provided adjacent to the second portion (320). Two grooves (GV) may be provided, respectively at both ends of the first portion (310). Since the groove (GV) has a sunken shape, an external fastening part may be inserted into the groove (GV). Specifically, a cap (400, see FIG. 7) described below may include a fastening part inserted into the groove (GV).

[0085] The insulating layer (300) may include refractory silicone. For example, the insulating layer (300) may be formed by molding refractory silicone on the outer surface of the body portion (210, FIG. 5) of the bus bar (200). Unlike general silicone materials that burn when exposed to flame or at high temperatures, refractory silicone can be ceramized at high temperatures. Therefore, the refractory silicone does not burn when exposed to flame but is ceramized, thereby maintaining insulation properties for the bus bar (200). For example, the refractory silicone can be ceramized at a temperature of 500 degrees Celsius or higher and 1700 degrees Celsius or lower. However, the temperature range at which the refractory silicone is ceramized is not limited thereto. The refractory silicone may include a silicone polymer and silica. For example, the applied silicone polymer may be a polysiloxane series compound having a vinyl group as a functional group, and may serve as a base material for the refractory silicone material. For example, the silica applied may be fumed silica, a reinforcing filler included in a silicone polymer. A high-purity silicon chloride (SiCl4) compound can be manufactured using metallic silicon as the main raw material through a reaction with hydrochloric acid and a purification process. Fumed silica can be obtained by reacting this with hydrogen and oxygen in a high-temperature flame. Furthermore, the refractory silicon may include platinum (Pt) as a catalyst.

[0086] When refractory silicone is exposed to flame or high heat, the silicone polymer decomposes and silica (SiO2) cross-links, forming a ceramic material. An insulating layer (300) comprising refractory silicone according to one embodiment maintains electrical insulation properties by being ceramicized rather than burning or melting, even when exposed to flame or in a high-temperature environment.

[0087] Accordingly, the insulating layer (300) can insulate the body part (210, see FIG. 5) of the bus bar (200) even in flames or at high temperatures, thereby preventing the bus bar (200) from coming into contact with other electrical components or conductive members, thereby causing a short circuit.

[0088] Referring to FIGS. 7 to 14, a busbar assembly of one embodiment will be described.

[0089] Figure 7 is a plan view of a busbar assembly of one embodiment.

[0090] Figure 8 is a side view of a busbar assembly of one embodiment.

[0091] FIGS. 9 to 11 are each cross-sectional views of a busbar assembly of one embodiment.

[0092] In the drawings of FIGS. 7 to 11 below, for convenience of explanation, a cap (400) is provided at one end (220a, 220b) of a bus bar (200a, 200b), and one end (220a, 220b) is illustrated as not having a cap (400). However, this is for explanation, and the bus bar assembly (100) of the present invention includes caps (400) provided at both ends (220a, 220b) of the bus bars (200a, 200b), as illustrated in FIG. 12.

[0093] Referring to FIG. 7, a busbar assembly (100) of one embodiment includes a plurality of busbars (200a, 200b), an insulating layer (300a, 300b), and a cap (400).

[0094] A plurality of bus bars (200a, 200b) include a first bus bar (200a) and a second bus bar (200b) that are arranged to face each other. The first bus bar (200a) connects a first battery module (1200a) and a second battery module (1200b), and the second bus bar (200b) connects a third battery module (1200c) and a fourth battery module (1200d). At this time, the third battery module (1200c) faces the first battery module (1200a), and the fourth battery module (1200d) faces the second battery module (1200b), so that the first bus bar (200a) and the second bus bar (200b) are arranged to face each other. Meanwhile, the description of the aforementioned bus bar (200) applies equally to each of the first bus bar (200a) and the second bus bar (200b).

[0095] The busbar assembly (100) includes a first insulating layer (300a) surrounding the outer surface of a first busbar (200a) and a second insulating layer (300b) surrounding the outer surface of a second busbar (200b). The description of the insulating layer (300) described above applies equally to the first insulating layer (300a) and the second insulating layer (300b).

[0096] The cap (400) is provided to insulate the ends (220a, 220b) of the bus bars (200a, 200b). The cap (400) according to one embodiment of the present invention simultaneously covers the respective ends of the first bus bar (200a) and the second bus bar (200b). Specifically, the cap (400) simultaneously covers one end (220a) of the first bus bar (200a) and one end of the second bus bar (200b) facing it. Since the cap (400) covers the adjacent ends (220a, 220b) at once, even if the size of the bus bars (200a, 200b) becomes larger compared to the distance between the battery modules (1200a, 1200b, 1200c, 1200d), the adjacent bus bars (200a, 200b) can be effectively insulated.

[0097] Referring to FIGS. 7, 8, and 11 together, a cap (400) according to one embodiment includes a body (410), a fastening portion (420), and a partition wall (430). The body (410) is a portion surrounding the ends (220a, 220b). The cap (400) is coupled to the insulating layers (300a, 300b) as the body (410) surrounds the second portion (320a, 320b) of the insulating layers (300a, 300b). The fastening portion (420) is a portion extending from the body (410). The fastening portion (420) extends from the end portion (220a, 220b) of the bus bar (200a, 200b) toward the body portion (210a, 210b) and can be inserted into a groove (GV) formed in the insulating layer (300a, 300b). When the fastening portion (420) is inserted into the groove (GV) of the insulating layer (300a, 300b), the cap (400) can be stably fixed to the insulating layer (300a, 300b) without shaking left and right.

[0098] At this time, the groove (GV) can secure sufficient depth by being formed within the third portion (330a, 330b) extending upward from the upper surface of the first portion (310a, 310b) of the insulating layer (300a, 300b). If the third portion (330a, 330b) is omitted and the groove (GV) is formed directly on the upper surface of the first portion (310a, 310b) of the insulating layer (300a, 300b), it may be difficult to secure sufficient depth of the groove (GV) due to the body portion (210a, 210b) arranged inside the insulating layer (300a, 300b).

[0099] Meanwhile, each of the first insulating layer (300a) and the second insulating layer (300b) may be provided by injection molding the first part (310a, 310b), the second part (320a, 320b), and the third part (330a, 330b) into an integral shape.

[0100] Referring to FIGS. 7 to 10 together, a partition wall (430) is disposed between one end (220a) of the first bus bar (200a) and one end (220b) of the second bus bar (200b). The partition wall (430) may extend in a first direction (DR1), which is the longitudinal direction of the first bus bar (200a), to insulate one end (220a) of the first bus bar (200a) from one end (220b) of the second bus bar (200b). The interior of the cap (400) is divided into a first space (SP1) and a second space (SP2) by a partition wall (430), and one end (220a) of a first bus bar (200a) is placed in the first space (SP1), and one end (220b) of a second bus bar (200b) is placed in the second space (SP2). In addition, fastening members such as bolts can be stored in the first space (SP1) and the second space (SP2) during a later assembly process.

[0101] In addition, the bulkhead (430) may extend in the thickness direction of the first bus bar (200a) so that the ends thereof protrude lower than the ends (220a, 220b). Accordingly, an insulating distance (ID) between the ends (220a, 220b) may be secured, thereby improving the insulation of the bus bar assembly (100).

[0102] Meanwhile, the thickness of the main body (410) and the partition wall (430) may be set to contact the second portion (320b) as shown in FIG. 10. Accordingly, in the cross-sectional view of FIG. 9 where the second portion (320b) does not exist, a space may exist between the ends (220a, 220b) and the main body (410) and between the ends (220a, 220b) and the partition wall (430). However, FIG. 9 illustrates one embodiment, and the thickness may be adjusted as needed to modify the main body (410) and the partition wall (430) so that they contact the ends (220a, 220b) as well as in FIG. 9.

[0103] In one embodiment, the cap (400) may include any one of refractory plastic, mica, and refractory silicone. Accordingly, the cap (400) may exhibit excellent refractory properties.

[0104] When exposed to flame, refractory plastics can block flames for a certain period of time without forming holes or drips. Specifically, refractory plastics can protect internal structures by forming a carbonized layer in the flame. The refractory plastic may contain at least one of the following materials: polyphenylene oxide (PPO), polyamide (PA), and polybutylene terephthalate (PBT).

[0105] Mica has excellent fire resistance, heat resistance, high temperature resistance and electrical insulation properties, so it can act as a fire-resistant insulating layer without burning in flames or high temperatures.

[0106] In one embodiment, the elasticity of the insulating layer (300a, 300b) may be greater than the elasticity of the cap (400). Due to the elasticity of the insulating layer (300a, 300b), the cap (400) can be strongly fixed to the insulating layer (300a, 300b) without a separate adhesive layer. Specifically, when the cap (400) is tightly fitted into the groove (GV) formed in the insulating layer (300a, 300b), the relatively elastic insulating layer (300a, 300b) is compressed, so that the cap (400) can be inserted into the groove (GV), and after being inserted, the cap (400) can be fixed into the groove (GV) due to the elasticity of the insulating layer (300a, 300b). Accordingly, the conventional tape (AL, see Fig. 1) for fixing the cap (400) to the insulating layer (300a, 300b) can be omitted.

[0107] Figure 12 is a plan view of a busbar assembly of one embodiment.

[0108] Fig. 12 illustrates that caps (400) are provided at both ends of the first bus bar (200a) and the second bus bar (200b). Fig. 12 is the final structure of the bus bar assembly (100) illustrated in Fig. 7.

[0109] Referring to FIG. 12, each cap (400) can insulate the side surface of the end (220a) of the first bus bar (200a) and the end (220b) of the second bus bar (200b) that are arranged adjacent to each other, including a bulkhead (430).

[0110] Figure 13 is a plan view of a busbar assembly of one embodiment.

[0111] Referring to FIG. 13, a busbar assembly (100-1) of one embodiment may include one cap (400-1) provided at both ends of a first busbar (200a) and a second busbar (200b). Specifically, in FIG. 12, the partition walls (430) included in the caps (400) provided at both ends may be connected to each other to form a partition wall (430-1) having an integral shape. In this case, the side surfaces of the first busbar (200a) and the second busbar (200b) that are arranged adjacent to each other may be completely insulated.

[0112] Figure 14 is a plan view of a busbar assembly of one embodiment.

[0113] Referring to FIG. 14, the busbar assembly (100-2) of one embodiment may further include a glass fiber layer (500). The glass fiber layer (500) may include a first glass fiber layer (500a) that surrounds a first insulating layer (300a) and a second glass fiber layer (500b) that surrounds a second insulating layer (300b). The glass fiber layers (500a, 500b) may physically protect the internal structure. For example, the glass fiber layers (500a, 500b) may prevent the insulating layers (300a, 300b) from being directly exposed to external flames. In a flame or high-temperature environment, when the insulating layers (300a, 300b) are ceramicized, the electrical insulation properties of the insulating layers (300a, 300b) may be maintained, but the strength may be weakened and the insulating layers (300a, 300b) may be broken by external force. The glass fiber layers (500a, 500b) are provided to wrap the insulating layers (300a, 300b), thereby preventing the insulating layers (300a, 300b) from being broken by external force. For example, the glass fiber layers (500a, 500b) are provided in the form of glass fiber tape, and may be formed by winding them multiple times on the insulating layers (300a, 300b). The busbar assembly (100-2) of one embodiment includes the glass fiber layer (500), thereby improving structural rigidity and maintaining excellent insulation performance even when exposed to flame.

[0114] Meanwhile, the embodiments of the busbar assembly of the present invention are not limited to the above.

[0115] Fig. 15 is a plan view of a busbar provided with an insulating layer according to one embodiment.

[0116] Referring to Fig. 15, an insulating layer (300-1) of one embodiment may be provided on a bus bar (200). For convenience of explanation, a cap (400-2) is provided only on one end (220) of the bus bar (200), and the other end (220) is shown as being exposed without the cap (400-2) being provided.

[0117] The insulating layer (300-1) may include a first portion (310) that wraps around the body portion (210, see FIG. 5) of the bus bar (200) and a second portion (320-1) that wraps around a portion of the end portion (220). The insulating layer (300-1) may be provided by injection molding so that the first portion (310) and the second portion (320-1) have an integral shape.

[0118] A groove (GV-1) having a sunken shape is formed in the insulating layer (300-1). In one embodiment, the groove (GV-1) is formed along the periphery of the second portion (320-1) of the insulating layer (300-1) and may be formed adjacent to the first portion (310). The groove (GV-1) may be provided in two pieces, and may be formed in the second portion (320-1) at each end. The cap (400-2) described below may be fixed to the insulating layer (300-1) by having at least a portion thereof inserted into the groove (GV-1) when provided in the second portion (320-1).

[0119] Referring to FIGS. 16 to 22, a busbar assembly (100-3) to which the busbar (200) and the insulating layer (300-1) of FIG. 15 are applied will be described.

[0120] Figure 16 is a plan view of a busbar assembly of one embodiment.

[0121] Figure 17 is a side view of a busbar assembly of one embodiment.

[0122] Fig. 18 is a cross-sectional view of a busbar assembly of one embodiment.

[0123] Figure 19 is a cross-sectional view of a busbar assembly of one embodiment.

[0124] Figure 20 is a rear view of a busbar assembly of one embodiment.

[0125] In the drawings of FIGS. 16 to 22 below, for convenience of explanation, a cap (400-2) is provided at one end (220a, 220b) of a bus bar (200a, 200b), and one end (220a, 220b) is illustrated as not having a cap (400-2). However, this is for explanation, and the bus bar assembly (100-3) of the present invention includes two caps (400-2) provided at both ends (220a, 220b) of the bus bar (200a, 200b).

[0126] Referring to FIG. 16, a busbar assembly (100-3) of one embodiment includes a first busbar (200a), a second busbar (200b), an insulating layer (300a-1, 300b-1), and a cap (400-2).

[0127] The same content as described above in Fig. 7 applies to the first bus bar (200a) and the second bus bar (200b).

[0128] The insulating layers (300a-1, 300b-1) include a first insulating layer (300a-1) that surrounds the outer surface of the first bus bar (200a) and a second insulating layer (300b-1) that surrounds the outer surface of the second bus bar (200b). The description of the insulating layer (300-1) described above in FIG. 15 applies equally to the first insulating layer (300a-1) and the second insulating layer (300b-1).

[0129] The cap (400-3) is provided to insulate the ends (220a, 220b) of the bus bars (200a, 200b). According to one embodiment of the present invention, the cap (400-3) simultaneously covers the respective ends of the first bus bar (200a) and the second bus bar (200b). Specifically, the cap (400-3) simultaneously covers one end (220a) of the first bus bar (200a) and one end of the second bus bar (200b) facing it. Since the cap (400-3) covers the adjacent ends (220a, 220b) at once, even if the size of the busbar (200a, 200b) becomes larger compared to the distance between the battery modules (1200a, 1200b, 1200c, 1200d), the adjacent busbars (200a, 200b) can be effectively insulated.

[0130] The description of the material of the cap (400-3) may be applied in the same manner as described above in FIG. 7. That is, the cap (400-3) may include any one of refractory plastic, mica, and refractory silicone. In addition, the elasticity of the insulating layer (300a, 300b) may be greater than the elasticity of the cap (400).

[0131] Referring to FIGS. 16 to 20 together, a cap (400-2) according to one embodiment includes a body (410) and a partition wall (430). That is, compared to the caps (400, 400-1) of one embodiment described above with reference to FIGS. 7 to 14, the cap (400-2) does not include a fastening portion (410, see FIG. 7). This is because the method by which the cap (400-2) and the insulating layers (300a-1, 300b-1) are coupled is different from the method described with reference to FIGS. 7 to 14.

[0132] The main body (410) of the cap (400-2) surrounds the ends (220a, 220b) and the second portion (320a-1, 320b-1) of the insulating layer (300a-1, 300b-1), and is coupled to the insulating layer (300a-1, 300b-1). Specifically, referring to FIG. 18, a portion of the main body (410) is inserted into the groove (GV-1) when covering the second portion (320a-1, 320b-1). Accordingly, the main body (410) can be stably coupled to the insulating layer (300a-1, 300b-1) without being peeled off. Accordingly, the conventional cap fixing tape (AL, refer to FIG. 1) can be omitted.

[0133] Referring to FIGS. 16, 17, and 19 together, a partition wall (430) is disposed between one end (220a) of the first bus bar (200a) and one end (220b) of the second bus bar (200b). The partition wall (430) may extend in a first direction (DR1), which is the longitudinal direction of the first bus bar (200a), to insulate one end (220a) of the first bus bar (200a) from one end (220b) of the second bus bar (200b). The interior of the cap (400) is divided into a first space (SP1) and a second space (SP2) by a partition wall (430), and one end (220a) of a first bus bar (200a) is arranged in the first space (SP1), and one end (220b) of a second bus bar (200b) is arranged in the second space (SP2). In addition, a bolt (BT) can be accommodated in each of the first space (SP1) and the second space (SP2). The bolt (BT) is inserted into the through hole (HH) to fix the ends (220a, 220b) to the battery modules (1200a, 1200a, 1200a, 1200d).

[0134] In addition, the bulkhead (430) may extend in the thickness direction of the first bus bar (200a) so that the ends thereof protrude lower than the ends (220a, 220b). Accordingly, an insulating distance (ID) between the ends (220a, 220b) may be secured, thereby improving the insulation of the bus bar assembly (100).

[0135] Meanwhile, in FIG. 19, a space may exist between the ends (220a, 220b) and the main body (410) and between the ends (220a, 220b) and the partition wall (430). However, this is only one embodiment, and as described above in FIG. 9, the thickness may be adjusted as needed to modify the main body (410) and the partition wall (430) so that they come into contact with the ends (220a, 220b).

[0136] Referring to Fig. 20, the main body (410) is provided to be in contact with the outer surfaces of the insulating layers (300a-1, 300b-1). Accordingly, a separation space may exist between the main body (410) and the ends (220a, 220b) on the back surface. In Fig. 20, the inner surface of the main body (410) is shown as being visible on the back surface through the separation space. However, the embodiment is not limited thereto, and the main body (410) may also be provided to be in contact with the ends (220a, 220b). A partition wall (430) may be arranged between the ends (220a, 220b) to insulate the ends (220a, 220b) from each other.

[0137] Meanwhile, the embodiment of the cap (400-2) is not limited thereto.

[0138] Figure 21 is a cross-sectional view of a busbar assembly of one embodiment.

[0139] Figure 22 is a rear view of a busbar assembly of one embodiment.

[0140] Referring to FIGS. 21 and 22, the cap (400-3) of one embodiment may further include a protrusion (440) protruding from the partition wall (430). The protrusions (440) may be provided in multiple numbers, protruding from the left and right sides of the partition wall (430). Specifically, the protrusions (440) may protrude from the partition wall (430) toward the ends (220a, 220b). The upper surface of the protrusion (440) may contact the lower surface of the ends (220a, 220b), thereby preventing the cap (400-3) from being peeled off upward. In this case, the cap (400-3) may include a material such as refractory silicone, and may have a predetermined elasticity. During the assembly process, when the cap (400-3) is fastened to the ends (220a, 220b) from top to bottom, the protrusion (440) may be temporarily compressed by the ends (220a, 220b), and after the fastening is completed, the shape of the protrusion (440) may be restored so that the upper surface of the protrusion (440) may be in contact with the lower surface of the end (220a, 220b). Although not illustrated, the protrusion (440) may also be applied to the cap (400) included in the busbar assembly (100) described in FIG. 7.

[0141] Meanwhile, the embodiment of FIG. 13 described above may also be applied to the busbar assembly (100-3) described above in FIGS. 16 to 22. That is, the two caps (400-2) included in the busbar assembly (100-3) may have a single shape by being connected to each other by the partition walls (430). Accordingly, the side surfaces of the first busbar (200a) and the second busbar (200b) arranged adjacent to each other may be completely insulated.

[0142] In addition, the embodiment of FIG. 14 described above can also be applied to the busbar assembly (100-3) described above in FIGS. 16 to 22. That is, the busbar assembly (100-3) can further include a glass fiber layer (500). The glass fiber layer (500) can include a first glass fiber layer (500a) that wraps a first portion (310a) of a first insulating layer (300a) and a second glass fiber layer (500b) that wraps a first portion (310b) of a second insulating layer (300b).

[0143]

[0144] The busbar assembly of the present invention includes caps that simultaneously cover the ends of adjacent first and second busbars, thereby effectively insulating adjacent busbars even when the busbars are larger than the distance between battery modules. Accordingly, a busbar assembly with a simpler structure than conventional busbars while exhibiting improved insulation and fire resistance can be provided.

[0145]

[0146] In this example, terms indicating directions such as front, back, left, right, up, and down are used, but these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0147] One or more battery modules according to the above-described embodiment can be mounted together with various control and protection systems such as a BMS (Battery Management System), a BDU (Battery Disconnect Unit), and a cooling system to form a battery pack.

[0148] The above battery module or battery pack can be applied to various devices. Specifically, it can be applied to transportation vehicles such as electric bicycles, electric vehicles, and hybrid vehicles, as well as ESS (Energy Storage Systems), but is not limited thereto. It can also be applied to various devices that can use secondary batteries.

[0149] Although the 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 made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention.

[0150] [Explanation of symbols]

[0151] 100: Busbar assembly

[0152] 200: Busbar

[0153] 200a: Busbar 1

[0154] 200b: Second bus bar

[0155] 210: Body

[0156] 220: End

[0157] 300: Insulating layer

[0158] 300a: 1st insulation layer

[0159] 300b: Second insulation layer

[0160] 310: Part 1

[0161] 320: Part 2

[0162] 330: Part 3

[0163] 400: Cap

[0164] 410: Body

[0165] 420: Fastening

[0166] 430: Bulkhead

[0167] 500: Glass fiber layer

[0168] 1000: Battery Pack

[0169] 1100: Pack Frame

[0170] 1200: Battery module

[0171] 1300: BDU module

[0172] 1400: BMS module

Claims

1. First busbar and second busbar arranged parallel to each other; Each of the first bus bar and the second bus bar includes a body portion and an end portion extending from both ends of the body portion and having a through hole defined therein, A first insulating layer surrounding the outer circumference of the first bus bar; A second insulating layer surrounding the outer surface of the second bus bar; and A busbar assembly comprising a cap that simultaneously surrounds the end of the first busbar and the end of the second busbar, which are adjacent to each other.

2. In paragraph 1, The above cap is a busbar assembly including a partition wall disposed between the end of the first busbar and the end of the second busbar.

3. In paragraph 2, The cap includes a first space and a second space separated by the bulkhead, The end of the first bus bar is placed in the first space, A busbar assembly in which the end of the second busbar is arranged in the second space.

4. In paragraph 2, The above caps are provided in multiples at both ends of the first bus bar and the second bus bar, A busbar assembly in which the bulkheads included in the plurality of caps are connected to each other by extending in the longitudinal direction of the first busbar.

5. In paragraph 2, A busbar assembly in which the bulkhead extends in the thickness direction of the first busbar and has an end protruding lower than the end of the first busbar and the end of the second busbar.

6. In paragraph 5, The above cap further includes protrusions protruding left and right from the bulkhead, A busbar assembly in which the upper surface of the protrusion is in contact with the lower surface of the end of the first busbar and the lower surface of the end of the second busbar.

7. In paragraph 1, A groove having a sunken shape is formed in each of the first insulating layer and the second insulating layer, The above cap is a busbar assembly including a fastening member inserted into the above groove.

8. In paragraph 7, Each of the first insulating layer and the second insulating layer, A busbar assembly comprising a first portion that surrounds the body portion and a second portion that extends from the first portion and surrounds a portion of the end portion and is covered by the cap.

9. In paragraph 8, A busbar assembly in which two grooves are provided on the upper surface of the first part and formed adjacent to the second part.

10. In paragraph 8, The above groove is a busbar assembly formed along the perimeter of the second portion.

11. In paragraph 1, A busbar assembly wherein the first insulating layer and the second insulating layer have greater elasticity than the cap.

12. In paragraph 1, A busbar assembly further comprising a glass fiber layer surrounding the first insulating layer and the second insulating layer.

13. In paragraph 1, A busbar assembly wherein the first insulating layer and the second insulating layer comprise refractory silicone.

14. In paragraph 1, The above cap is a busbar assembly comprising any one of refractory plastic, mica, and refractory silicone.

15. At least one busbar assembly according to paragraph 1; battery modules; A BDU (battery disconnect unit) module for controlling the electrical connection of the above battery modules; and Includes a BMS (Battery Management System) module that monitors and controls the operation of the above battery module, A battery pack wherein at least one busbar assembly electrically connects at least one of the battery modules, the battery module and the BDU module, the battery module and the BMS module, and the BDU module and the BMS module.

Images