Busbar assembly and battery pack containing it

Abstract

A busbar assembly according to one embodiment of the present invention includes: a busbar that is connected to a battery module inside a battery pack and guides electrical connection of the battery module; a first insulating layer that surrounds the outer periphery of the busbar and has grooves formed on both ends; a second insulating layer that surrounds the first insulating layer; and caps that include a body that surrounds both ends of the busbar and fixing portions that are inserted into the grooves.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2023 - 0105717, filed on August 11, 2023, and all the contents disclosed in the literature of the Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a bus bar assembly and a battery pack including the same, and more particularly, to a bus bar assembly with improved insulation stability and a battery pack including the same.

Background Art

[0003] In modern society, the use of portable devices such as mobile phones, laptops, video cameras, and digital cameras has become common, and the development of technologies in the fields related to such mobile devices has been active. In addition, rechargeable secondary batteries are a solution to solve problems such as air pollution in existing gasoline vehicles that use fossil fuels, and are used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), plug - in hybrid electric vehicles (P - HEVs), etc., and the need for the development of secondary batteries is increasing.

[0004] Current commercially available secondary batteries include nickel - cadmium batteries, nickel - metal hydride batteries, nickel - zinc batteries, lithium secondary batteries, etc. Among these, lithium secondary batteries have attracted attention for their advantages such as almost no memory effect compared to nickel - based secondary batteries, free charging and discharging, very low self - discharge rate, and high energy density.

[0005] Such lithium secondary batteries mainly use lithium - based oxides and carbon materials as the positive electrode active material and the negative electrode active material, respectively. A lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate coated with such positive electrode active material and negative electrode active material are arranged with a separator therebetween, and a battery case for hermetically storing the electrode assembly together with an electrolyte.

[0006] Generally, lithium secondary batteries can be classified into two types based on the shape of their casing: can-type secondary batteries, in which the electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which the electrode assembly is housed in a pouch made of aluminum laminate sheet.

[0007] For secondary batteries used in small devices, two to three battery cells are typically arranged. However, for secondary batteries used in medium to large devices such as automobiles, battery modules are used, which electrically connect multiple battery cells. Such battery modules improve capacity and output by connecting multiple battery cells in series or parallel to form a stack of battery cells. Furthermore, one or more battery modules can be mounted together with various control and protection systems such as BDUs (Battery Disconnect Units), BMSs (Battery Management Systems), and cooling systems to form a battery pack.

[0008] In battery packs, where multiple battery modules are assembled, the heat generated by the multiple battery cells accumulates in a confined space, potentially causing a rapid increase in temperature. In other words, while battery modules with stacked battery cells and battery packs equipped with such modules can achieve high output, if the heat dissipation of the battery cells is not performed properly, or if thermal runaway occurs in the battery cells, there is a high possibility of continuous ignition and subsequent explosion.

[0009] On the other hand, the battery pack is equipped with busbars that connect to the battery modules.

[0010] Figure 1 shows exploded perspective and joined perspective views of a conventional busbar assembly.

[0011] Referring to Figure 1, a conventional busbar assembly 10 includes a busbar 20, a covering 20C enclosing the busbar 20, a cap (CP), and tape (AL) for securing the cap (CP). The busbar 20 is a rod-shaped metal member extending along its length. Through holes (HH) can be formed at both ends of the busbar 20 for connection to the terminal busbars of the battery module. Such a busbar 20 is responsible for the HV (High Voltage) connection in the battery pack. HV connection refers to the connection of the power source role for supplying power, and the busbar 20 is responsible for guiding the electrical connections of the battery module and is generally made of a metal material with good electrical conductivity. As an example, the busbar 20 may be made of copper (Cu).

[0012] The covering 20C can enclose the busbar 20. The covering 20C may contain an electrically insulating material, such as silicon or epoxy. Because the covering 20C encloses the busbar 20 through which high current flows, it prevents the busbar 20 from coming into contact with other electrical components or conductive materials other than the terminal busbar of the battery module, thus preventing short circuits.

[0013] Fastening members are inserted into the through-holes (HH) of the busbar 20, allowing the busbar 20 to be connected to the terminal busbar of the battery module. Caps (CP) are attached to both ends of the busbar 20 for insulation. The caps (CP) may be, for example, rubber caps. The caps (CP) can be attached to the covering 20C using tape (AL).

[0014] However, when a flame is generated inside the battery pack, the flame is extremely hot, at approximately 1000°C, which could melt the covering 20C surrounding the busbar 20, or the cap (CP) and tape (AL), potentially exposing the busbar 20. If the exposed busbar 20 comes into contact with other conductive materials and causes a short circuit, the internal flame could spread further, potentially propagating to the outside of the battery pack. Ultimately, this could lead to the explosion of the battery pack or the vehicle in which it is installed.

[0015] Therefore, there is a need for technological development of busbar assemblies that can maintain electrical insulation even if a flame occurs inside the battery pack. [Overview of the project] [Problems that the invention aims to solve]

[0016] The problem that this invention aims to solve is to provide a busbar assembly and a battery pack including the same that can maintain excellent electrical insulation even if a flame is generated inside the battery pack.

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

[0018] The busbar assembly of the present invention includes a busbar that connects to a battery module inside a battery pack and guides the electrical connections of the battery module; a first insulating layer that encloses the outer surface of the busbar and has grooves formed at both ends; a second insulating layer that encloses the first insulating layer; and a cap that encloses both ends of the busbar and includes a fixing portion that is inserted into the grooves.

[0019] In one embodiment, the thickness of the fixed portion is greater than the thickness of the first insulating layer, the lower part of the fixed portion is bonded to the first insulating layer, and the second insulating layer can be in contact with the upper part of the fixed portion.

[0020] In one embodiment, the second insulating layer can be disposed between the fixing portions disposed at both ends of the bus bar.

[0021] In one embodiment, the thickness of the fixing portion is the same as the thickness of the first insulating layer, the fixing portion and the first insulating layer are located in the same layer, and the second insulating layer can be disposed on the fixing portion and the first insulating layer.

[0022] In one embodiment, a tape can be disposed between the second insulating layer and the fixing portion.

[0023] In one embodiment, the second insulating layer can have a tube shape including glass fibers.

[0024] In one embodiment, the outer surface of the second insulating layer may be coated with silicon.

[0025] In one embodiment, the second insulating layer may not include an adhesive substance.

[0026] In one embodiment, the fixing portion includes a plurality of protruding portions spaced apart from each other, and the groove can include a plurality of spaced recessed portions into which the protruding portions can be inserted.

[0027] In one embodiment, the fixing portion includes a shape of an extended block, and the groove can have a groove into which the block is inserted.

[0028] In one embodiment, the first insulating layer can include refractory silicon.

[0029] The battery pack of the present invention includes at least one busbar assembly; a battery module; a BDU (battery disconnect unit) module for controlling the electrical connections of the battery module; and a BMS (Battery Management System) module for monitoring and controlling the operation of the battery module, wherein the at least one busbar assembly electrically connects at least one of the following: between the battery modules, between the battery module and the BDU module, between the battery module and the BMS module, and between the BDU module and the BMS module. [Effects of the Invention]

[0030] The busbar assembly of the present invention minimizes the use of adhesive for bonding the cap and the insulating layer, and can maintain good insulation and fire resistance even when exposed to flames.

[0031] The effects of the present invention are not limited to those described above, and other effects not mentioned will be clearly understood by those skilled in the art from the claims. [Brief explanation of the drawing]

[0032] [Figure 1] These are exploded perspective and joined perspective views of a conventional busbar assembly. [Figure 2] This is a plan view of a battery pack according to one embodiment. [Figure 3] Figure 2 is a perspective view of one of the battery modules included in the battery pack. [Figure 4] Figure 3 is a partial perspective view showing the battery module with the module frame and end plate removed. [Figure 5] This is a plan view of a busbar provided with an insulating layer according to one embodiment. [Figure 6] This is a plan view of a cap in one embodiment. [Figure 7] This is a plan view of a busbar provided with a cap and insulating layer in one embodiment. [Figure 8] This is a plan view of a cap in one embodiment. [Figure 9] This is a plan view of a busbar provided with a cap and insulating layer according to one embodiment. [Figure 10] This is a plan view showing one step in the manufacturing method of a busbar assembly according to one embodiment. [Figure 11] This is a plan view showing one step in the manufacturing method of a busbar assembly according to one embodiment. [Figure 12] This is a plan view showing one step in the manufacturing method of a busbar assembly according to one embodiment. [Figure 13] This is a plan view showing one step in the manufacturing method of a busbar assembly according to one embodiment. [Figure 14] This is a cross-sectional view of a busbar assembly in one embodiment. [Figure 15] This is a cross-sectional view of a busbar assembly in one embodiment. [Figure 16] This is a cross-sectional view of a busbar assembly in one embodiment. [Modes for carrying out the invention]

[0033] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings, so that they can be easily implemented by a person with ordinary skill in the art to which the present invention pertains. The present invention can be implemented in several different forms and is not limited to the embodiments described herein.

[0034] To clearly explain the present invention, irrelevant parts have been omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

[0035] Furthermore, the dimensions and thicknesses of each component shown in the drawings are arbitrarily indicated for the sake of explanation, and therefore the present invention is not necessarily limited to those shown. In the drawings, the thicknesses are shown enlarged to clearly represent multiple layers and regions. Also, in the drawings, the thicknesses of some layers and regions are shown exaggerated for the sake of explanation.

[0036] Furthermore, when a layer, membrane, region, plate, or other part is "on top of" or "on top of" another part, this includes not only when it is "directly above" the other part, but also when there is another part in between. When one part is "directly above" another part, it means that there is no other part in the middle. Also, when a part is "on top of" or "on top of" a reference part, it means that it is located above or below the reference part, and does not necessarily mean that it is located "on top of" or "on top of" the reference part in the opposite direction of gravity.

[0037] Furthermore, throughout the specification, when a part "includes" a certain component, unless otherwise stated, it means that it may include other components rather than excluding them.

[0038] Furthermore, throughout the specification, "on a plane" means when the subject is viewed from above, and "on a cross-section" means when the cross-section obtained by cutting the subject perpendicularly is viewed from the side.

[0039] Furthermore, throughout this 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) can intersect perpendicularly to each other. Throughout this specification, the concepts of up and down are described as being distinguished along the third direction (DR3). Specifically, the up or upper direction means the third direction (DR3). The down or lower direction means the direction opposite to the third direction (DR3). In this specification, "thickness" means the length measured from the third direction (DR3).

[0040] Figure 2 is a plan view of a battery pack according to one embodiment.

[0041] Referring to Figure 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 the electrical connections of the battery modules 1200, and a BMS (battery management system) module 1400 for monitoring and controlling the operation of the battery modules 1200. In this embodiment, at least one busbar assembly 100 electrically connects at least one of the following: between 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, multiple battery modules 1200 can be housed in the pack frame 1100, and the electrical connections between the battery modules 1200 and between the battery modules 1200 and the BDU module 1300 can be made by the busbar assembly 100. In other words, the busbar assembly 100 according to this embodiment can handle HV (High Voltage) coupling. Here, HV coupling refers to the coupling of power sources that supply power requiring high voltage, and means coupling between battery cells or between battery modules.

[0042] On the other hand, the BDU module 1300 is a component for controlling the electrical connection of the battery module 1200 and can interrupt the power supply between the power converter and the battery module 1200. The BDU module 1300 can ensure the safety of the battery pack 1000 by interrupting the power supply to the battery pack 1000 when conditions occur that cause the current to exceed a set range.

[0043] On the other hand, the LV connecting member 100' according to this embodiment can be responsible for the electrical connection between the battery module 1200 and the BMS module 1400. The electrical connection here is an LV (Low voltage) connection, meaning a sensing connection for sensing and controlling the voltage and temperature of the battery module 1200. Specifically, sensors such as those inside the battery module 1200 are arranged, and real-time temperature and voltage information of the battery module 1200 is transmitted to the BMS module 1400 through the LV connecting member 100'. The real-time operating state of the battery module 1200 can be monitored and controlled through the BMS module 1400. Although not specifically shown, an HV current sensor may be integrated into the BMS module 1400. In this case, the busbar assembly according to this embodiment can be responsible for the electrical connection between the battery module 1200 and the BMS module 1400, or between the BDU module 1300 and the BMS module 1400.

[0044] The battery module 1200 according to this embodiment will be described with reference to Figures 3 and 4. However, the battery module 1200 described below is one exemplary structure of a battery module including multiple battery cells 11, and various forms of battery modules including multiple battery cells can be applied.

[0045] Figure 3 is a perspective view showing one of the battery modules included in the battery pack shown in Figure 2.

[0046] Figure 4 is a partial perspective view showing the battery module from Figure 3 with the module frame and end plate removed.

[0047] Referring to Figures 3 and 4, the battery module 1200 according to this embodiment may include a battery cell stack 11A in which multiple battery cells 11 are stacked. The battery cell stack 11A is shown in Figure 4. Such a battery cell stack 11A can be housed in a module frame 30 and an end plate 40.

[0048] The battery cell 11 may be a pouch-type battery cell. Such a pouch-type battery cell can be formed by housing an electrode assembly in a pouch case made of a laminate sheet containing a resin layer and a metal layer, and then fusing the outer periphery of the pouch case. However, the battery cell 11 of the present invention is not limited to a pouch-type battery cell.

[0049] In one embodiment, the battery cell 11 can be formed in a rectangular sheet structure. The electrode leads 11L connected to the electrode assembly protrude outside the pouch case, but the electrode leads 11L of each battery cell 11 can be electrically connected to each other via a lead busbar 21. On the other hand, at least one electrode lead 11L can be connected to a terminal busbar 22. A portion of the terminal busbar 22 can be exposed outside the battery module 1200, as shown in Figure 3. Both the lead busbar 21 and the terminal busbar 22 can be made of a metal material with excellent electrical conductivity.

[0050] The busbar assembly 100 according to this embodiment can be electrically connected to such a terminal busbar 22, resulting in the HV connection described above. In other words, the battery module 1200 can be electrically connected to other battery modules 1200, BDU modules 1300, or BMS modules 1400 via the busbar assembly 100 connected to the terminal busbar 22.

[0051] The following describes a busbar assembly according to one embodiment.

[0052] Figure 5 is a plan view of a busbar provided with an insulating layer according to one embodiment.

[0053] Referring to Figure 5, the busbar 200 guides the electrical connections within the battery pack 1000 (see Figure 2). The busbar 200 is configured to guide the electrical connections, i.e., HV connections, of the battery module 1200 (see Figure 2), and may include a metal material with excellent electrical conductivity. For example, the busbar 200 may be made of copper (Cu). The busbar 200 may have a rod shape extending in one direction. Through holes (HH) are defined at both ends of the busbar 200. Fastening members are inserted into the through holes (HH) to connect the busbar 200 and the terminal busbar 22 (see Figure 3) of the battery module 1200 (see Figure 3).

[0054] The first insulating layer 300 is provided so as to enclose the busbar 200. At this time, the through-holes (HH) of the busbar 200 are exposed from the first insulating layer 300 and can be electrically connected to the terminal busbar 22 (see Figure 3) of the battery module 1200 (see Figure 3).

[0055] The first insulating layer 300 may contain a refractory material. Specifically, the first insulating layer 300 may also contain refractory silicone. For example, the first insulating layer 300 can be formed by molding refractory silicone onto the outer surface of the busbar 200. Unlike general silicone materials that are exposed to flames or burn at high temperatures, refractory silicone can be ceramicized at high temperatures. Therefore, when exposed to flames, refractory silicone can be ceramicized without burning, maintaining its insulating properties to the busbar 200. For example, refractory silicone can be ceramicized at temperatures between 500 degrees Celsius and 1700 degrees Celsius. However, the temperature range in which refractory silicone is ceramicized is not limited to this. Refractory silicone can contain silicone polymers and silica. For example, the silicone polymer used may be a polysiloxane compound having a vinyl group as a functional group, which can serve as the base material for the refractory silicone material. For example, the silica used may be fumed silica, used as a reinforcing filler in the silicon polymer. High-purity silicon chloride (SiCl4) compounds can be produced using metallic silicon as the main raw material through a reaction with hydrochloric acid and a purification process, and fumed silica can be obtained by reacting this with hydrogen and oxygen in a high-temperature flame. Furthermore, refractory silicon may contain platinum (Pt) as a catalyst.

[0056] When refractory silicon is exposed to flames or high temperatures, decomposition of the silicon polymer occurs, along with cross-linking of silica (SiO2), forming a ceramic material. In one embodiment, the first insulating layer 300 containing refractory silicon does not burn or melt even when exposed to flames or placed in a high-temperature environment, but rather ceramicizes, maintaining its electrical insulation properties. Therefore, the first insulating layer 300 does not burn even in the presence of flames or high temperatures, insulating the busbar 200 and preventing the busbar 200 from coming into contact with other electrical components or conductive members and causing a short circuit.

[0057] Grooves (GV) are formed at both ends of the first insulating layer 300. The grooves (GV) have a shape that is recessed inward from both ends of the first insulating layer 300. In one embodiment, the grooves (GV) may include a plurality of recessed portions that are spaced apart from each other. The grooves (GV) are a structure for coupling with the cap 400, which will be described later.

[0058] Figure 6 is a plan view of a cap according to one embodiment.

[0059] Figure 7 is a plan view of a busbar provided with a cap and insulating layer according to one embodiment.

[0060] Referring to both Figures 6 and 7, the cap 400 covers both ends of the busbar 200, and in particular the through-hole (HH). Although not shown, after the fastening member is inserted into the through-hole (HH), the cap 400 covers both ends of the busbar 200 and the fastening member. Therefore, the cap 400 has space for housing the fastening member. For the sake of explanation, the process by which the busbar 200 is connected to the terminal busbar 22 (see Figure 3) by the fastening member is omitted in this drawing. The cap 400 is also coupled to the first insulating layer 300, preventing the busbar 200 from being exposed to the outside and preventing short circuits of the busbar 200.

[0061] Cap 400 may contain a fire-resistant material. In one embodiment, cap 400 may contain one of the following: fire-resistant plastic, mica, or fire-resistant silicone. This allows cap 400 to exhibit excellent fire resistance.

[0062] Fire-resistant plastics can block flames by preventing holes or drips from forming for a certain period of time when exposed to flames. Specifically, fire-resistant plastics can protect internal structures by forming a carbonized layer in the flame. Fire-resistant plastics may also contain at least one of the following materials: PPO (Polyphenylene Oxide), PA (Polyamide), and PBT (Polybutylene Terephthalate).

[0063] Mika has excellent fire resistance, heat resistance, high temperature resistance, and electrical insulation properties, and can act as a fire-resistant insulating layer without burning in flames or high temperatures.

[0064] The same provisions described above can be applied to the first insulating layer 300 with respect to the fire-resistant silicone.

[0065] The cap 400 of the present invention includes a body 410 and a fixing portion 420. As described above, the body 410 covers both ends of the busbar 200 and has a space for housing fastening members. The fixing portion 420 is inserted into a groove (GV) of the first insulating layer 300 so that the cap 400 is connected to the first insulating layer 300. The fixing portion 420 may have a shape for insertion into the groove (GV), and in one embodiment, the fixing portion 420 may include a plurality of spaced-apart protrusions. The fixing portion 420 may be provided integrally with the body 410, but the embodiment is not limited thereto. By connecting the fixing portion 420 including a plurality of protrusions to a groove (GV) including a plurality of recesses, the bonding force between the cap 400 and the first insulating layer 300 can be strengthened.

[0066] Figure 8 is a plan view of a cap according to one embodiment.

[0067] Figure 9 is a plan view of a busbar provided with a cap and insulating layer according to one embodiment.

[0068] Referring to both Figures 8 and 9, the cap 400-1 includes a body 410 and a fixing portion 420-1, and in one embodiment, the fixing portion 420-1 may include a projection extending in one direction. In one embodiment, the first insulating layer 300-1 may include a recess extending in one direction to conform to the shape of the fixing portion 420-1. Having a unidirectional shape for the fixing portion 420-1 can increase the adhesive area between the tape subsequently applied to the cap 400-1 and the cap 400-1, thereby increasing the adhesive strength.

[0069] The following description will use a busbar assembly 100 having the structure of the first insulating layer 300 and cap 400 shown in Figures 6 and 7 as an example. However, the contents described below can be applied identically to a busbar assembly having the structure of the first insulating layer 300-1 and cap 400-1 shown in Figures 8 and 9.

[0070] Figure 10 is a plan view showing one step in the manufacturing method of a busbar assembly according to one embodiment.

[0071] Figure 11 is a plan view showing one step in the manufacturing method of a busbar assembly according to one embodiment.

[0072] Figure 12 is a plan view showing one step in the manufacturing method of a busbar assembly according to one embodiment.

[0073] Figure 13 is a plan view showing one step in the manufacturing method of a busbar assembly according to one embodiment.

[0074] An example of a method for manufacturing a busbar assembly will be described with reference to Figures 10 to 13.

[0075] Referring to Figure 10, a method for manufacturing a busbar assembly according to one embodiment includes the step of providing a second insulating layer 500 on a first insulating layer 300. The second insulating layer 500 is provided so as to wrap around the first insulating layer 300. Specifically, after the cap 400 and the first insulating layer 300 are joined at one end of the busbar 200, the second insulating layer 500 can be provided so as to wrap around the first insulating layer 300. The second insulating layer 500 may be provided in a tubular shape. Specifically, the second insulating layer 500 provided in a tubular shape can wrap around the first insulating layer 300 and be fitted in the longitudinal direction (Ld) of the busbar 200.

[0076] The second insulating layer 500 of the present invention may not contain any other adhesive substance. The adhesive substance may include, for example, at least one of epoxy resin, silicone resin, and acrylic resin. By not including an adhesive substance in the second insulating layer 500, it is possible to prevent harmful gases from being generated from the adhesive substance when a flame occurs, thereby preventing deterioration of the insulating properties of the busbar assembly.

[0077] Referring to Figure 11, after the second insulating layer 500 is provided on the first insulating layer 300, the cap 400 is provided on the other end of the first insulating layer 300. The fixing part 420 is inserted into the groove (GV) formed on the other end of the first insulating layer 300, and the cap 400 is fixed to the other end of the first insulating layer 300.

[0078] Referring to Figure 12, after the caps 400 are attached to both ends of the busbar 200 (see Figure 10), the second insulating layer 500 spreads out to contact the fixing portions 420 at both ends. The second insulating layer 500 can be fixed by fitting both ends between the fixing portions 420 of the caps 400, instead of using an adhesive. A more detailed explanation will follow in Figures 15 and 16.

[0079] Referring to both Figures 12 and 13, a tape 600 can be provided on the fixing portion 420 to form a busbar assembly 100 of one embodiment. The tape 600 can be provided to cover the fixing portion 420 and a portion of the second insulating layer 500. The tape 600 can also strengthen the bonding force between the cap 400 and the second insulating layer 500 and improve the insulation of the busbar assembly 100. The tape 600 may include, for example, a glass fiber layer. The glass fiber layer can physically protect the internal structure; for example, the glass fiber layer can prevent the first insulating layer 300 from being directly exposed to external flames. If the first insulating layer 300 is ceramicized in a flame or high-temperature environment, the electrical insulation of the first insulating layer 300 can be maintained, but its strength will be weakened and it may break due to external forces. The glass fiber layer can be provided to wrap around the first insulating layer 300 and prevent the first insulating layer 300 from being broken by external forces. In one embodiment, the busbar assembly 100 includes a tape 600 containing a glass fiber layer, which improves structural rigidity and maintains good insulation performance even when exposed to flames. On the other hand, the tape 600 contains an adhesive layer in addition to the glass fiber layer because it is adhesive. However, the tape 600 is used in small quantities, and the second insulating layer 500, which conventionally used glass fiber tape, can be replaced with a glass fiber tube that does not contain adhesive, thereby minimizing the generation of harmful gases due to the ignition of the adhesive when the busbar assembly 100 is exposed to flames.

[0080] Figure 14 is a cross-sectional view of a busbar assembly according to one embodiment.

[0081] Figure 14 is a cross-sectional view of an example of the busbar assembly 100 shown in Figure 13, cut along the A-A' line. Referring to Figure 14, the first insulating layer 300 encloses the outer surface of the busbar 200, and the second insulating layer 500 encloses the outer surface of the first insulating layer 300.

[0082] In one embodiment, the second insulating layer 500 may include a glass fiber layer 510 and a coating layer 520. The glass fiber layer 510 is the aforementioned glass fiber layer, and may be provided in a tubular shape without including another adhesive layer. The coating layer 520 may be formed by coating the outer surface of the glass fiber layer 510 with silicone. The second insulating layer 500, including the coating layer 520, can further improve fire resistance.

[0083] Figure 15 is a cross-sectional view of a busbar assembly according to one embodiment.

[0084] Figure 15 is a cross-sectional view of one embodiment of the busbar assembly 100 shown in Figure 13, cut along the B-B' cutting line. Referring to Figure 15, the thickness (H1) of the fixing portion 420 of the cap 400 may be greater than the thickness (T1) of the first insulating layer 300. This allows the first insulating layer 300 to contact the lower part (PT1) of the fixing portion 420 when the fixing portion 420 is coupled to the first insulating layer 300, while the remaining upper part (PT2) of the fixing portion 420 is exposed from the first insulating layer 300. The upper part (PT2) of the fixing portion 420 can serve as a locking portion for fixing the second insulating layer 500. Specifically, the second insulating layer 500 is fitted and fixed between the upper parts (PT2) of the fixing portion 420.

[0085] Referring to Figures 10-13 and Figure 15, in Figures 10 and 11, the second insulating layer 500 is fitted to contact the upper part (PT2) of the fixing part 420 provided at one end. In Figure 12, the second insulating layer 500 is fitted and fixed between the upper parts (PT2) of the fixing parts 420 provided at both ends. Therefore, even without the second insulating layer 500 containing another adhesive, the fixing part 420 contained in the cap 400 can stably fix the second insulating layer 500 without it moving along the length of the busbar 200. In addition, the tape 600 can improve the structural rigidity within the busbar assembly 100 while further bonding the fixing part 420 and the second insulating layer 500. The tape 600 may be omitted if necessary.

[0086] On the other hand, the embodiments of cap 400 are not limited to these.

[0087] Figure 16 is a cross-sectional view of a busbar assembly according to one embodiment.

[0088] Figure 16 is a cross-sectional view of one embodiment of the busbar assembly 100 shown in Figure 13, cut along the B-B' line. Referring to Figure 16, in one embodiment of the cap 400-2, the thickness (H2) of the fixing portion 420-2 can be the same as the thickness (T1) of the first insulating layer 300. This allows the first insulating layer 300 and the fixing portion 420-2 to be placed in the same layer when the fixing portion 420-2 is bonded to the first insulating layer 300. To ensure fixing force, tape 600 can be provided to tape the cap 400-2 and the first insulating layer 300. Subsequently, a second insulating layer 500 can be provided to wrap around the fixing portion 420-2, the tape 600, and the first insulating layer 300. Specifically, the second insulating layer 500, having a tubular shape, can be fitted to wrap around the outer circumferential surfaces of the tape 600 and the first insulating layer 300. As a result, the tape 600 is placed between the second insulating layer 600 and the fixing part 420. In the embodiment shown in Figure 16, the second insulating layer 500 is placed and fixed between the bodies 410 of the caps 400-2 provided at both ends. On the other hand, the tape 600 can be omitted if necessary.

[0089] The busbar assembly of the present invention includes a cap with a fixing portion and a first insulating layer with a groove into which the fixing portion can be inserted, minimizing the amount of adhesive used to bond the cap and the first insulating layer, and preventing the release of harmful gases from the adhesive during flame exposure, which can degrade the insulating properties. Furthermore, the second insulating layer, which is placed on the first insulating layer, is provided in a tubular shape without adhesive, and the second insulating layer can be fixed by the caps at both ends without adhesive. As a result, the busbar assembly of the present invention can maintain good insulating and fire-resistant properties even when exposed to flames.

[0090] In this embodiment, terms indicating directions such as front, back, left, right, up, and down were used. However, these terms are for explanatory convenience and may differ depending on the position of the object in question, the observer's position, etc.

[0091] 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.

[0092] The aforementioned battery modules and battery packs can be applied to a variety of devices. Specifically, they can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrids, as well as ESS (Energy Storage Systems), but are not limited to these; they can be applied to a variety of devices that can use secondary batteries.

[0093] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concepts of the present invention as defined in the following claims also fall within the scope of the present invention. [Explanation of Symbols]

[0094] 100 Busbar Assembly 200 bus bar 300 First insulating layer GV groove 400 caps 410 Main Unit 420 Fixed part 500 Second insulating layer 600 Tapes

Claims

1. A busbar connected to the battery module inside the battery pack, which guides the electrical connection of the battery module, A first insulating layer that encloses the outer surface of the busbar and has grooves formed at both ends, A second insulating layer enclosing the first insulating layer, and A cap comprising a main body that encloses both ends of the busbar and a fixing part that is inserted into the groove. Includes, The first insulating layer contains a fire-resistant material, The thickness of the fixed portion is greater than the thickness of the first insulating layer. The lower part of the fixed portion is coupled to the first insulating layer, The second insulating layer is a busbar assembly that is in contact with the upper part of the fixed portion.

2. The busbar assembly according to claim 1, wherein the second insulating layer is disposed between the fixing portions located at both ends of the busbar.

3. A busbar connected to the battery module inside the battery pack, which guides the electrical connection of the battery module, A first insulating layer that encloses the outer surface of the busbar and has grooves formed at both ends, A second insulating layer enclosing the first insulating layer, and A cap comprising a main body that encloses both ends of the busbar and a fixing part that is inserted into the groove. Includes, The first insulating layer contains a fire-resistant material, The thickness of the fixed portion is the same as the thickness of the first insulating layer. The fixed portion and the first insulating layer are located in the same layer. The second insulating layer is a busbar assembly disposed on the fixed portion and the first insulating layer.

4. The busbar assembly according to claim 3, wherein a tape is placed between the second insulating layer and the fixing portion.

5. A busbar connected to the battery module inside the battery pack, which guides the electrical connection of the battery module, A first insulating layer that encloses the outer surface of the busbar and has grooves formed at both ends, A second insulating layer enclosing the first insulating layer, and A cap comprising a main body that encloses both ends of the busbar and a fixing part that is inserted into the groove. Includes, The first insulating layer contains a fire-resistant material, The second insulating layer is a busbar assembly having a tubular shape containing glass fibers.

6. The busbar assembly according to claim 5, wherein the outer surface of the second insulating layer is coated with silicon.

7. A busbar connected to the battery module inside the battery pack, which guides the electrical connection of the battery module, A first insulating layer that encloses the outer surface of the busbar and has grooves formed at both ends, A second insulating layer enclosing the first insulating layer, and A cap comprising a main body that encloses both ends of the busbar and a fixing part that is inserted into the groove. Includes, The first insulating layer contains a fire-resistant material, The second insulating layer is a busbar assembly that does not contain adhesive material.

8. The fixing portion includes a plurality of protrusions spaced apart from each other, The busbar assembly according to any one of claims 1, 3, 5, and 7, wherein the groove includes a plurality of spaced recesses into which the protrusion can be inserted.

9. The aforementioned fixing portion includes the shape of an extended block, The busbar assembly according to any one of claims 1, 3, 5, and 7, wherein the groove is a groove into which the block is inserted.

10. The busbar assembly according to any one of claims 1, 3, 5, and 7, wherein the fire-resistant material is fire-resistant silicone.

11. At least one busbar assembly according to any one of claims 1, 3, 5, and 7; Battery module; A BDU (battery disconnect unit) module for controlling the electrical connections of the battery module; and It includes a Battery Management System (BMS) module that monitors and controls the operation of the aforementioned battery module, The battery pack comprises at least one busbar assembly that electrically connects at least one of the following: between the battery modules, between the battery modules and the BDU module, between the battery modules and the BMS module, and between the BDU module and the BMS module.

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