Battery pack

Abstract

According to an exemplary embodiment of the present invention, a battery pack is provided. The battery pack includes a housing, a first battery assembly and a second battery assembly disposed on the housing, each of the first battery assembly and the second battery assembly including a plurality of pouch-type battery cells, and further includes a bus bar assembly disposed on the first battery assembly and the second battery assembly, and the bus bar assembly includes a bus bar frame covering the first battery assembly and the second battery assembly, and a plurality of inter-bus bars disposed on the bus bar frame.

Description

[[TECHNICAL FIELD]]

[0001] The present invention relates to a battery pack. The present application claims the benefit of Korean Application No. 2023-0046196 filed on April 7, 2023, which is hereby incorporated by reference in its entirety herein. [[BACKGROUND ART]]

[0002] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. Secondary batteries are widely used as energy sources for various wireless devices such as handsets, laptop computers, and wireless vacuum cleaners. In recent years, due to improvements in energy density and economies of scale, the manufacturing cost per unit capacity of secondary batteries has decreased dramatically, and as the cruising range of battery electric vehicles (BEV) has increased to a level comparable to that of fuel vehicles, the main application of secondary batteries has shifted from mobile devices to mobility.

[0003] The trend of technological development for secondary batteries for mobility is the improvement of energy density and safety. Here, the energy density of a secondary battery is the value obtained by dividing the maximum electrical energy that the secondary battery can store by the mass of the secondary battery. Since the high energy density of a secondary battery is directly related to the driving efficiency and cruising range of mobility, various studies have been conducted to improve the energy density of secondary batteries. [[SUMMARY OF THE INVENTION]] [[Problem to be Solved by the Invention]]

[0004] The problem to be solved by the technical idea of the present invention is to provide a battery pack with improved energy density. [[Means for Solving the Problem]]

[0005] According to an exemplary embodiment of the present invention for solving the above-mentioned problems, a battery pack is provided. The battery pack includes a housing, a first battery assembly and a second battery assembly disposed on the housing, each of the first and second battery assemblies comprising a plurality of pouch-type battery cells, and further comprising a busbar assembly disposed on the first and second battery assemblies, wherein the busbar assembly comprises a busbar frame covering the first and second battery assemblies, and a plurality of interbusbars disposed on the busbar frame.

[0006] Each of the plurality of pouch-type battery cells includes a pouch case, a positive lead, and a negative lead, the pouch case includes a first side facing the housing and a second side opposite to the first side, the positive lead and negative lead of each of the plurality of pouch-type battery cells are located on the second side, and furthermore, the positive lead and negative lead of each of the plurality of pouch-type battery cells are connected to the corresponding interbus bars.

[0007] The positive lead and negative lead of each of the above-mentioned pouch-type battery cells are welded to the corresponding interbusbars from among the above-mentioned interbusbars.

[0008] One of the above-mentioned negative lead of the multiple pouch-type battery cells is in contact with the upper surface of the corresponding one of the above-mentioned multiple interbus bars.

[0009] The busbar frame described above includes a plurality of lead slots, and furthermore, the positive lead and negative lead of each of the plurality of pouch-type battery cells pass through the corresponding lead slots among the plurality of lead slots.

[0010] The busbar assembly includes a fireproof sheet interposed between the first and second battery assemblies and the busbar frame.

[0011] The busbar frame includes multiple holes, the fireproof sheet includes multiple cutout guides, and each of the multiple cutout guides overlaps with a corresponding hole.

[0012] According to an exemplary embodiment, a battery pack is provided. The battery pack includes a housing, first to fourth battery assemblies disposed on the housing, each of the first to fourth battery assemblies comprising a plurality of pouch-type battery cells, a center beam interposed between the first and second battery assemblies and the third and fourth battery assemblies, and a busbar assembly disposed on the first to fourth battery assemblies, the busbar assembly comprising a busbar frame covering the first to fourth battery assemblies.

[0013] The busbar frame described above covers the center beam described above.

[0014] Each of the above-mentioned plurality of pouch-type battery cells includes a pouch case, a positive lead, and a negative lead, wherein the pouch case includes a first side facing the housing and a second side opposite to the first side, and the positive lead and negative lead of each of the plurality of pouch-type battery cells are located on the second side.

[0015] The busbar assembly includes a plurality of interbusbars arranged on the busbar frame, and the positive lead and negative lead of each of the plurality of pouch-type battery cells are connected to the corresponding interbusbars.

[0016] The positive lead and negative lead of each of the above-mentioned pouch-type battery cells are welded to the corresponding interbusbars from among the above-mentioned interbusbars.

[0017] The positive lead and negative lead of any one of the above-mentioned pouch-type battery cells are separated from each of the above-mentioned interval busbars.

[0018] One of the negative lead cells of the above-mentioned pouch-type battery cells is in contact with the upper surface of the above-mentioned busbar frame. [Effects of the Invention]

[0019] An exemplary embodiment of the present invention includes a battery pack with a busbar frame that covers multiple battery assemblies. This reduces the number of steps in the assembly process and the number of components assembled during the manufacture of the secondary battery, which can reduce the manufacturing cost of the secondary battery and improve the productivity of the secondary battery.

[0020] The effects that can be obtained from exemplary embodiments of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly derived and understood by a person of ordinary skill in the art to which the exemplary embodiments of this disclosure belong, from the following description. That is, unintended effects associated with carrying out exemplary embodiments of this disclosure can also be derived by a person of ordinary skill in the art from exemplary embodiments of this disclosure. [Brief explanation of the drawing]

[0021] [Figure 1] This is a perspective view illustrating a battery pack according to an exemplary embodiment. [Figure 2] This is an exploded perspective view illustrating a battery pack according to an exemplary embodiment. [Figure 3] This shows the pouch-type battery cells in the battery pack. [Figure 4] This shows the busbar assembly of the battery pack. [Figure 5] It is a partial plan view showing an enlarged portion of FIG. 1 [Figure 6] It is a cross-sectional view taken along section line 5I-5I' of FIG. 5 [Figure 7] It is a partial cross-sectional view showing an enlarged portion of FIG. 6 [Figure 8] It is a perspective view for explaining a battery pack according to an exemplary embodiment [Figure 9] It is an exploded perspective view of the battery pack of FIG. 8 [Figure 10] It is an exploded perspective view of the bus bar assembly of FIG. 8 [Figure 11] In the battery pack of FIG. 8, a portion corresponding to FIG. 7 is shown [Figure 12] It is a perspective view showing a battery pack according to an exemplary embodiment [Figure 13] It is an exploded perspective view of the battery pack of FIG. 12 DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to that, the terms and words used in the present specification and claims shall not be construed as being limited to their ordinary or dictionary meanings, but may be interpreted as meanings and concepts consistent with the technical idea of the present invention based on the principle that the inventor may properly define the concept of terms for the purpose of describing his own invention in the best manner

[0023] Therefore, the embodiments described in the present specification and the configurations shown in the drawings are only the most preferred embodiment of the present invention, and do not represent all the technical ideas of the present invention, so that various equivalents and modifications that can substitute for these are possible as of the filing date of the present application

[0024] In addition, in the description of the present invention, if it is determined that a detailed description of a related known structure or function may obscure the gist of the present invention, the detailed description thereof will be omitted

[0025] Since embodiments of the present invention are provided to give a more complete explanation to an ordinary person of the art, the shapes and sizes of components in the drawings may be exaggerated, omitted, or shown schematically for the sake of clarity. Accordingly, the sizes and proportions of each component do not fully reflect the actual sizes and proportions.

[0026] (First Embodiment) Figure 1 is a perspective view illustrating a battery pack 100 according to an exemplary embodiment.

[0027] Figure 2 is an exploded perspective view illustrating a battery pack 100 according to an exemplary embodiment.

[0028] Figure 3 is a side view of the pouch-type battery cell 121.

[0029] Referring to Figures 1 to 3, the battery pack 100 may include a housing 110, a number of battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, 120_6 (hereinafter 120_1 to 120_6), a center beam 130, busbar assemblies 140_1, 140_2, and a cross busbar 150. The battery pack 100 is the final form of a battery system to be installed in a mobility device or the like.

[0030] The housing 110 may provide space for arranging multiple battery assemblies 120_1 to 120_6. The housing 110 may include a support plate 110P and side walls 110S.

[0031] The two directions substantially parallel to the support plate 110P are defined as the X and Y directions, and the direction substantially perpendicular to the support plate 110P is defined as the Z direction. Each of the X, Y, and Z directions may be substantially perpendicular to one another. Unless otherwise stated, the definitions of directions are the same for the following drawings. In addition, in the description of the multiple battery assemblies 120_1 to 120_6, the X, Y, and Z directions are defined based on the case where the multiple battery assemblies 120_1 to 120_6 are arranged on the battery pack 100.

[0032] The support plate 110P may include multiple plates joined to each other by friction stir welding. The support plate 110P may include multiple cooling channels, which are flow paths for the cooling fluid. The support plate 110P may include multiple cavities, which may reduce the weight of the support plate 110P. Each of the multiple cooling channels and multiple cavities may extend in the X direction.

[0033] The side wall 110S may be coupled to the support plate 110P. The side wall 110S may extend in the Z direction. The side wall 110S may include an internal empty space, which may reduce its weight. Part of the side wall 110S may be substantially perpendicular to the Y direction, and part of the side wall 110S may be substantially perpendicular to the X direction.

[0034] Multiple battery assemblies 120_1 to 120_6 can be placed on a support plate 110P of the housing 110. The support plate 110P can support the multiple battery assemblies 120_1 to 120_6. The side wall 110S can horizontally enclose the multiple battery assemblies 120_1 to 120_6.

[0035] Multiple battery assemblies 120_1 to 120_6 may include multiple pouch-type battery cells 121, a first crossbeam 125a, and a second crossbeam 125b. Battery assembly 120_1 may be referred to as the first battery assembly, battery assembly 120_2 as the second battery assembly, battery assembly 120_3 as the third battery assembly, battery assembly 120_4 as the fourth battery assembly, battery assembly 120_5 as the fifth battery assembly, and battery assembly 120_6 as the sixth battery assembly.

[0036] According to exemplary embodiments, multiple pouch-type battery cells 121 can be connected in series and / or in parallel. For example, multiple pouch-type battery cells 121 can be connected in series with each other. For another example, multiple pouch-type battery cells 121 can be connected in parallel with each other. For yet another example, multiple pouch-type battery cells 121 connected in parallel can form multiple banks, and these multiple banks can be connected in series with each other.

[0037] Each of the multiple pouch-type battery cells 121 may include an electrode assembly, an electrolyte, and a pouch case 121C.

[0038] The electrode assembly housed in the battery case includes a positive electrode, a negative electrode, and a separator membrane interposed between the positive and negative electrodes. Electrode assemblies are classified into jelly roll type and stack type depending on their assembly configuration. A jelly roll type electrode assembly consists of a winded positive electrode, a negative electrode, and a separator membrane interposed between them. A stack type electrode assembly includes multiple positive electrodes, multiple negative electrodes, and multiple separator membranes interposed between them, stacked sequentially. The positive electrode of the electrode assembly may be connected to a positive electrode lead 121P. The negative electrode of the electrode assembly may be connected to a negative electrode lead 121N.

[0039] The pouch case 121C may include a storage section 121B and a terrace 121T. The storage section 121B may provide space for storing an electrode assembly and may thus have a convex shape relative to the terrace 121T. The terrace 121T may be a sealed portion of the pouch case 121C. The terrace 121T may surround the storage section 121B.

[0040] Each pouch case 121C of the multiple pouch-type battery cells 121 may include first to fourth sides 121S1, 121S2, 121S3, and 121S4. The first side 121S1 of pouch case 121C may face the support plate 110P of the housing 110. The second side 121S2 of pouch case 121C may be opposite to the first side 121S1 of each of the multiple pouch-type battery cells 121. The third side 121S3 and fourth side 121S4 of pouch case 121C may connect the first side 121S1 and the second side 121S2 of pouch case 121C.

[0041] According to an exemplary embodiment, each of the plurality of pouch-type battery cells 121 may be a unidirectional cell. According to an exemplary embodiment, the positive lead 121P and negative lead 121N of each of the plurality of pouch-type battery cells 121 may be arranged in the same direction. According to an exemplary embodiment, the positive lead 121P and negative lead 121N of each of the plurality of pouch-type battery cells 121 may be located on the second side 121S2 of each pouch case 121C of the plurality of pouch-type battery cells 121. The positive lead 121P and negative lead 121N may protrude from the second side 121S2 of the pouch case 121C. The positive lead 121P and negative lead 121N may be spaced apart in the Y direction. The positive lead 121P may be located at one end of the second side 121S2 in the Y direction, and the positive lead 121P may be located at the other end of the second side 121S2 in the Y direction.

[0042] According to exemplary embodiments, each of the plurality of battery assemblies 120_1 to 120_6 may further include a plurality of separators 122 (see Figure 6) interposed between the plurality of pouch-type battery cells 121. The plurality of separators 122 (see Figure 6) can prevent the plurality of pouch-type battery cells 121 from swelling by horizontally supporting the plurality of pouch-type battery cells 121. According to exemplary embodiments, the plurality of separators 122 (see Figure 6) may be thermal barriers. According to exemplary embodiments, each of the plurality of separators 122 (see Figure 6) may have a high melting temperature and low thermal conductivity. According to exemplary embodiments, each of the plurality of separators 122 (see Figure 6) may include flame-retardant materials such as ceramics and coated glass fibers. According to an exemplary embodiment, each of the multiple separators 122 (see Figure 6) may also be configured to release a fire retarding material and a fire extinguishing agent in the event of a thermal runaway event.

[0043] The first crossbeam 125a of the battery assemblies 120_1 and 120_6, which are positioned on the outer casing, can be coupled to a first support beam 116a positioned on the support plate 110P of the housing 110. The first crossbeam 125a and the first support beam 116a can be fixed to the support plate 110P of the housing 110 by mechanical means such as bolts.

[0044] The second crossbeam 125b of the battery assemblies 120_3 and 120_5, which are positioned on the outer casing, can be coupled to the second support beam 116b. The second support beam 116b can be positioned on the second crossbeam 125b. The second crossbeam 125b and the second support beam 116b can be fixed to the support plate 110P of the housing 110 by mechanical means such as bolts.

[0045] The first crossbeam 125a and second crossbeam 125b of each of the battery assemblies 120_1 to 120_6 can be spaced apart from each other with a plurality of pouch-type battery cells 121 in between. The first crossbeam 125a and second crossbeam 125b can horizontally cover the plurality of pouch-type battery cells 121. The first crossbeam 125a and second crossbeam 125b can be fixed to the plurality of pouch-type battery cells 121 by an adhesive or the like.

[0046] According to exemplary embodiments, the first crossbeam 125a and the second crossbeam 125b may have different and complementary shapes. For example, the second crossbeam 125b of battery assembly 120_2 may be coupled with the first crossbeam 125a of battery assembly 120_3. The coupled first crossbeam 125a and second crossbeam 125b may constitute a crossbeam assembly CBA. Each of the first crossbeam 125a and second crossbeam 125b of the crossbeam assembly CBA can interlock with each other.

[0047] The center beam 130 may extend between the side walls 110S that are perpendicular to the X direction. The center beam 130 may extend in the X direction. The center beam 130 may isolate battery assemblies 120_1, 120_2, 120_5 from battery assemblies 120_3, 120_4, 120_6. The center beam 130 may be interposed between battery assemblies 120_1, 120_2, 120_5 and battery assemblies 120_3, 120_4, 120_6.

[0048] Each of the busbar assemblies 140_1 and 140_2 may be extended in the X direction. The X-direction length of each of the busbar assemblies 140_1 and 140_2 may be greater than the Y-direction length of each of the busbar assemblies 140_1 and 140_2. The busbar assemblies 140_1 and 140_2 may be separated from each other in the Y direction. In the Y direction, the center beam 130 may be interposed between the busbar assemblies 140_1 and 140_2. Each of the busbar assemblies 140_1 and 140_2 may be separated from the center beam 130 horizontally (for example, in the Y direction). Each of the busbar assemblies 140_1 and 140_2 may not overlap with the center beam 130 in the Z direction.

[0049] Each of the busbar assemblies 140_1 and 140_2 may cover a portion of the multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6. Each of the busbar assemblies 140_1 and 140_2 may be separated from a portion of the multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6.

[0050] Busbar assembly 140_1 may be positioned on battery assemblies 120_1, 120_2, and 120_5. Busbar assembly 140_1 may cover battery assemblies 120_1, 120_2, and 120_5. Busbar assembly 140_1 may overlap battery assemblies 120_1, 120_2, and 120_5 in the Z direction. Busbar assembly 140_1 may not cover battery assemblies 120_3, 120_4, and 120_6. Busbar assembly 140_1 may be separated horizontally (for example, in the Y direction) from battery assemblies 120_3, 120_4, and 120_6. Busbar assembly 140_1 may not overlap battery assemblies 120_3, 120_4, and 120_6 in the Z direction.

[0051] Busbar assembly 140_2 may be positioned on battery assemblies 120_3, 120_4, and 120_6. Busbar assembly 140_2 may cover battery assemblies 120_3, 120_4, and 120_6. Busbar assembly 140_2 may overlap battery assemblies 120_3, 120_4, and 120_6 in the Z direction. Busbar assembly 140_2 may not cover battery assemblies 120_1, 120_2, and 120_5. Busbar assembly 140_2 may be separated horizontally (for example, in the Y direction) from battery assemblies 120_1, 120_2, and 120_5. Busbar assembly 140_2 may not overlap battery assemblies 120_1, 120_2, and 120_5 in the Z direction.

[0052] In this example, two busbar assemblies 140_1 and 140_2, separated in the Y direction, cover battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6, each arranged in 3 columns in the X direction and 2 rows in the Y direction. Thus, such an arrangement of busbar assemblies 140_1 and 140_2 and battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 can be described as a 3x2 arrangement. Based on what is described herein, a typical technician in the industry can easily arrive at an MxN arrangement of busbar assemblies 140_1 and 140_2 and multiple battery assemblies 120_1 to 120_6, where M and N are any integers greater than or equal to 2.

[0053] The battery pack 100 may further include electrical components. These electrical components may include any electronic elements necessary to power the battery pack.

[0054] Electrical components may include, for example, a Battery Management System (BMS). The BMS may be configured to perform tasks such as monitoring, balancing, and controlling the battery pack. Monitoring of the battery pack 100 may include measuring the voltage and current of specific nodes within a plurality of battery assemblies 120_1 to 120_6, and measuring the temperature at a set location inside the battery pack 100. The battery pack 100 may include measuring instruments for measuring the aforementioned voltage, current, and temperature.

[0055] Balancing the battery pack 100 is an operation that reduces deviations between multiple battery assemblies 120_1 to 120_6. Control of the battery pack 100 includes preventing overcharging, over-discharging, and overcurrent. Through monitoring, balancing, and control, the battery pack 100 can operate under optimal conditions, thereby preventing shortening of the lifespan of each of the multiple battery assemblies 120_1 to 120_6.

[0056] The electrical components may further include a cooling system, a Power Relay Assembly (PRA), a safety plug, and the like. The cooling system may include a cooling fan. The cooling fan can prevent overheating of each of the battery assemblies 120_1 to 120_6 by circulating air inside the battery pack 100. The PRA may be configured to supply or cut off power from the high-voltage battery to an external load (e.g., the vehicle's motor). The PRA can protect the battery assemblies 120_1 to 120_6 and the external load (e.g., the vehicle's motor) by cutting off the power supply to the external load (e.g., the vehicle's motor) in situations where abnormal voltages occur, such as voltage surges.

[0057] The battery pack 100 may further include a lead plate coupled to a side wall 110S. The lead plate may cover elements located inside the battery pack 100, such as battery assemblies 120_1 to 120_6 and electrical components. The lead plate may be fixed to the side wall 110S by mechanical means, such as bolts.

[0058] The battery pack 100 may further include multiple exhaust devices. These exhaust devices may be installed on either the lead plate or the side wall 110S. The multiple exhaust devices may provide a path for releasing hot gases from inside the battery pack 100 to the outside in the event of a thermal runaway event occurring in some of the battery assemblies 120_1 to 120_6. This may delay thermal propagation and improve the stability of the battery pack 100.

[0059] Here, thermal runaway in multiple battery assemblies 120_1 to 120_6 is a state in which the temperature change in multiple battery assemblies 120_1 to 120_6 further accelerates that temperature change, resulting in an uncontrollable positive feedback loop. In a thermal runaway state, multiple battery assemblies 120_1 to 120_6 exhibit a rapid temperature increase and emit large amounts of high-pressure gas and combustion residue.

[0060] Figure 4 is an exploded perspective view of busbar assemblies 140_1 and 140_2 according to an exemplary embodiment.

[0061] Figure 5 is a magnified partial plan view of the POR portion of Figure 1.

[0062] Figure 6 is a cross-sectional view along the cutting line 5I-5I' in Figure 5.

[0063] Figure 7 is a magnified partial cross-sectional view of the area shown in Figure 6.

[0064] Referring to Figures 2 and 4-7, each of the busbar assemblies 140_1 and 140_2 may include a busbar frame 141, a number of fireproof sheets 143, and a number of interbusbars 145a, 145b, and 145c.

[0065] Each busbar frame 141 of busbar assemblies 140_1 and 140_2 may contain insulating material. Each busbar frame 141 of busbar assemblies 140_1 and 140_2 may extend in the X direction. Each busbar frame 141 of busbar assemblies 140_1 and 140_2 may include a plurality of holes 141H and a plurality of slots 141S. Each busbar frame 141 of busbar assemblies 140_1 and 140_2 may further include coupling holes 141C for coupling with a crossbeam assembly CBA. For example, mechanical coupling means such as long bolts may penetrate the crossbeam assembly CBA through the coupling holes 141C and be coupled to the support plate 110P of the housing 110.

[0066] Each of the multiple pouch-type battery cells 121's positive lead 121P and negative lead 121N can pass through the corresponding slot 141S. This allows each busbar frame 141 of the busbar assemblies 140_1 and 140_2 to horizontally support and protect each of the multiple pouch-type battery cells 121's positive lead 121P and negative lead 121N. The Y-direction length of each of the multiple slots 141S may be longer than the Y-direction length of each of the multiple slots 141S.

[0067] Multiple slots 141S can constitute a first slot array AR1 and a second slot array AR2. That is, the first slot array AR1 and the second slot array AR2 can each include multiple slots 141S arranged along the X direction. The first slot array AR1 is parallel to the X direction and may be located on the edge of the busbar frame 141 adjacent to the side wall 110S. The second slot array AR2 is parallel to the X direction and may be located on the edge of the busbar frame 141 adjacent to the center beam 130.

[0068] As a result, one of the positive lead 121P and negative lead 121N of each of the multiple pouch-type battery cells 121 may pass through the slot 141S of the first slot array AR1, and the other of the positive lead 121P and negative lead 121N of each of the multiple pouch-type battery cells 121 may pass through the slot 141S of the second slot array AR2. For example, if the positive lead 121P of the pouch-type battery cell 121 passes through the slot 141S of the first slot array AR1, the negative lead 121N of the pouch-type battery cell 121 may pass through the slot 141S of the second slot array AR2.

[0069] There may be multiple holes 141H between the first slot array AR1 and the second slot array AR2. The first slot array AR1 and the second slot array AR2 may be separated from each other with the multiple holes 141H in between. The multiple holes 141H may provide a path for exhausting hot gas in the event of a thermal runaway event in the battery pack 100. Each of the multiple slots 141S is for passing one of the thin positive lead 121P and negative lead 121N, while the multiple holes 141H are for exhausting hot gas, so the area of ​​each of the multiple holes 141H may be larger than the area of ​​each of the multiple slots 141S.

[0070] Multiple fireproof sheets 143 may be interposed between multiple pouch-type battery cells 121 and a busbar frame 141. As a non-limiting example, multiple fireproof sheets 143 may correspond one-to-one with multiple battery assemblies 120_1 to 120_6. That is, each of the multiple fireproof sheets 143 may have an area similar to each of the multiple battery assemblies 120_1 to 120_6 (e.g., an area perpendicular to the Z direction), and each of the multiple fireproof sheets 143 may cover one of the multiple battery assemblies 120_1 to 120_6.

[0071] A typical engineer in the industry could easily arrive at embodiments in which some of the multiple fireproof sheets 143 cover two or more of the multiple battery assemblies 121_1 to 121_6, or two or more fireproof sheets 143 cover one of the multiple battery assemblies 121_1 to 121_6, based on what has been described herein.

[0072] Multiple fireproof sheets 143 can overlap with multiple holes 141H. Multiple fireproof sheets 143 may not overlap with the first slot array AR1 and the second slot array AR2. Multiple fireproof sheets 143 may be separated horizontally (for example, in the Y direction) from each of the first slot array AR1 and the second slot array AR2. Multiple fireproof sheets 143 may be interposed between the first slot array AR1 and the second slot array AR2.

[0073] According to an exemplary embodiment, the multiple fireproof sheets 143 may include a fireproof material such as mica. Each of the multiple fireproof sheets 143 may include a plurality of cut guides 143G. Each of the plurality of cut guides 143G can overlap in the Z direction with a corresponding of the plurality of holes 141H of the busbar frame 141. The plurality of cut guides 143G can be formed by a non-cutting process of the plurality of fireproof sheets 143, for example, using a knife. When a thermal runaway event occurs due to the plurality of cut guides 143G, the plurality of fireproof sheets 143 in the portion where the plurality of cut guides 143G are formed can be easily ruptured, thereby allowing hot gases generated from the plurality of battery assemblies 120_1 to 120_6 to be released through the plurality of holes 141H.

[0074] Multiple interbusbars 145a, 145b, and 145c may be arranged on the busbar frame 141. The multiple interbusbars 145a, 145b, and 145c may include a conductive material such as metal. As a non-limiting example, interbusbar 145a may have a substantially "L" shape, interbusbar 145b may have a substantially "I" shape, and interbusbar 145c may have a substantially "C" shape.

[0075] Each of the interbus bars 145a may include a slot 145aS, each of the interbus bars 145b may include a slot 145bS, and each of the interbus bars 145c may include a slot 145cS. The slots 145aS, 145bS, and 145cS allow each of the multiple interbus bars 145a, 145b, and 145c to have a comb shape. The positive lead 121P and negative lead 121N of each of the multiple pouch-type battery cells 121 that have passed through the corresponding slots 141S may pass through the corresponding slots 145aS, 145bS, and 145cS.

[0076] The interbusbar 145a may be an external connection terminal for drawing voltages from multiple battery assemblies 120_1 to 120_6. One of the interbusbars 145a may output the positive potential of the multiple battery assemblies 120_1 to 120_6, and the other interbusbar 145a may output the negative potential of the multiple battery assemblies 120_1 to 120_6. One of the interbusbars 145a may be in contact with the positive lead 121P, and the other interbusbar 145a may be in contact with the negative lead 121N.

[0077] The interbus bar 145b may not overlap the crossbeam assembly CBA in the Z direction. The interbus bar 145b may be separated horizontally (for example, in the X direction) from the crossbeam assembly CBA. This allows the interbus bar 145b to be in contact with the relatively adjacent positive lead 121P and negative lead 121N.

[0078] Interbusbar 145c may overlap with the crossbeam assembly CBA in the Z direction. This may result in a relatively large distance between the positive lead 121P and the negative lead 121N in contact with the interbusbar 145b. As a result, each of the interbusbars 145b may include a comb-shaped section that is spaced apart from each other and a bridge connecting the comb-shaped sections.

[0079] Multiple interbusbars 145a, 145b, and 145c can be welded to the positive lead 121P and the negative lead 121N. This can improve the reliability of the electrical and mechanical coupling between the multiple interbusbars 145a, 145b, and 145c, the positive lead 121P, and the negative lead 121N.

[0080] The cross bus bar 150 may be positioned on bus bar assemblies 140_1 and 140_2. The cross bus bar 150 may overlap with bus bar assemblies 140_1 and 140_2 in the Z direction. The cross bus bar 150 may overlap with the center beam 130 in the Z direction. The cross bus bar 150 may have a substantially linear shape. The cross bus bar 150 may include a slot 150S1 that overlaps with bus bar assembly 140_1 and a slot 150S2 that overlaps with bus bar assembly 140_2. Slot 150S1 may be at the first end of the cross bus bar 150, and slot 150S2 may be at the second end of the cross bus bar 150. The first and second ends of the cross bus bar 150 may be opposite each other in the Y direction.

[0081] The crossbusbar 150 can be connected to some of the negative leads 121N of the pouch-type battery cells 121 of battery assembly 120_5 and some of the positive leads 121P of the pouch-type battery cells 121 of battery assembly 120_6. The crossbusbar 150 can be in contact with some of the negative leads 121N of the pouch-type battery cells 121 of battery assembly 120_5 and some of the positive leads 121P of the pouch-type battery cells 121 of battery assembly 120_6. The crossbusbar 150 can be welded to some of the negative leads 121N of the pouch-type battery cells 121 of battery assembly 120_5 and some of the positive leads 121P of the pouch-type battery cells 121 of battery assembly 120_6. The crossbus bar 150 can provide an electrical connection between some of the negative leads 121N of the pouch-type battery cells 121 of battery assembly 120_5 and some of the positive leads 121P of the pouch-type battery cells 121 of battery assembly 120_6.

[0082] In conventional battery packs, each battery assembly includes one or two busbar assemblies, which increases the mass of the battery pack and reduces its energy density and productivity. According to an exemplary embodiment, by providing busbar assemblies 140_1 and 140_2 that cover multiple battery assemblies 120_1 to 120_2, the number of parts and assembly steps in the battery pack 100 can be reduced. This can improve the energy density and productivity of the battery pack 100.

[0083] (Second Embodiment) Figure 8 is a perspective view illustrating a battery pack 101 according to an exemplary embodiment.

[0084] Figure 9 is an exploded perspective view of the battery pack 101 shown in Figure 8.

[0085] Figure 10 is an exploded perspective view of the busbar assemblies 140_1' and 140_2' shown in Figure 8.

[0086] Figure 11 shows the part of the battery pack 101 in Figure 8 that corresponds to Figure 7.

[0087] Referring to Figures 8 to 11, the battery pack 101 may include a housing 110, several battery assemblies 120_1 to 120_6, a center beam 130, busbar assemblies 140_1', 140_2', and a cross busbar 150. Since the housing 110 and the several battery assemblies 120_1 to 120_6 of the battery pack 101 are substantially the same as those described with reference to Figures 1 to 7, redundant descriptions of them will be omitted.

[0088] Each of the busbar assemblies 140_1' and 140_2' may include a busbar frame 141, a plurality of fireproof sheets 143, and an interbusbar 145a. The busbar frame 141, the plurality of fireproof sheets 143, and the interbusbar 145a are substantially the same as those described with reference to Figures 4 to 7, so redundant descriptions of them are omitted.

[0089] According to an exemplary embodiment, busbar assemblies 140_1' and 140_2' may differ from busbar assemblies 140_1 and 140_2 in Figure 4 in that they may not include interbusbars 145b and 145c.

[0090] As a result, some of the positive lead 121P and negative lead 121N of the pouch-type battery cell 121 may be separated from the interbus bar 145a. Some of the positive lead 121P and negative lead 121N of the pouch-type battery cell 121 may not be in contact with the interbus bar 145a.

[0091] The positive lead 121P and negative lead 121N, separated from the interbusbar 145a, can be welded to each other. The lowest of the welded positive lead 121P and negative lead 121N may be in contact with the upper surface 141U of the busbar frame 141. The upper surface 141U of the busbar frame 141 may be opposite to the lower surface 141L, which faces the multiple pouch-type battery cells 121. In contrast, the lowest of the welded positive lead 121P and negative lead 121N in the battery pack 100 of Figure 2 can be welded to the interbusbar 145b, as shown in Figure 7.

[0092] According to an exemplary embodiment, the other interbusbars 145b and 145c (see Figure 4) can be omitted, with the exception of the interbusbar 145a, which is an external output terminal, and the crossbusbar 150, which requires a relatively long length. This reduces the number of parts assembled during the manufacture of the battery pack 101, thereby reducing the production cost of the battery pack 101 and potentially improving the energy density of the battery pack 101.

[0093] (Third embodiment) Figure 12 is a perspective view showing a battery pack 102 according to an exemplary embodiment.

[0094] Figure 13 is an exploded perspective view of the battery pack 102 shown in Figure 12.

[0095] Referring to Figures 12 and 13, the battery pack 102 may include a housing 110, several battery assemblies 120_1 to 120_6, a center beam 130, a busbar assembly 140, and a crossbusbar 150. Since the housing 110 and the several battery assemblies 120_1 to 120_6 of the battery pack 102 are substantially the same as those described with reference to Figures 1 to 7, redundant descriptions of them will be omitted.

[0096] The busbar assembly 140 may include a first part 140P1 substantially identical to the busbar assembly 140_1 in Figure 4, a second part 140P2 substantially identical to the busbar assembly 140_2 in Figure 4, and a third part 140P3 connecting the first part 140P1 and the second part.

[0097] According to an exemplary embodiment, the busbar assembly 140 may cover each of the multiple battery assemblies 120_1 to 120_6. According to an exemplary embodiment, the busbar assembly 140 may overlap each of the multiple battery assemblies 120_1 to 120_6 in the Z direction. According to an exemplary embodiment, the busbar assembly 140 may cover the center beam 130. According to an exemplary embodiment, the busbar assembly 140 may overlap the center beam 130 in the Z direction.

[0098] The present invention has been described in more detail above through the drawings and embodiments. However, the configurations described in the drawings or embodiments described herein are merely one embodiment of the present invention and do not represent the entire technical concept of the present invention. Therefore, at the time of filing, there may be various equivalents and modifications that can substitute for them. [Explanation of Symbols]

[0099] 100, 101, 102 Battery Packs 110 Housing 110P Support Plate 110S side wall 116a First support beam 116b Second support beam 120_1~6, 121_1~6 Battery Assembly 121 Pouch-type battery cells 121B Storage compartment 121C Pouch Case 121N Negative Lead 121P Positive Lead 121S1 First Side 121S2 Second Side 121S3 Third Side 121S4 4th Side 121T Terrace 122 Separator 125a First Crossbeam 125b Second Crossbeam 130 Center Beam 140 Busbar Assembly 140P1 Part 1 140P2 2nd part 140P3 3rd part 141 Busbar Frame 141C Joint Hole 141H Hall 141L bottom surface 141S slot 141U top 143 Fire-resistant sheet 143G Cutting Guide 145a, 145b, 145c Interbusbar 145aS, 145bS, 145cS slots 150 Crossbus Bar 150S1, 150S2 slots AR1 First Slot Array AR2 2nd slot array CBA Crossbeam Assembly

Claims

1. housing, A first battery assembly and a second battery assembly disposed on the housing, wherein each of the first and second battery assemblies includes a plurality of pouch-type battery cells, and In a battery pack comprising a busbar assembly disposed on the first battery assembly and the second battery assembly, The aforementioned busbar assembly is A busbar frame covering the first battery assembly and the second battery assembly, Multiple interbus bars arranged on the busbar frame, and, A fire-resistant sheet interposed between the first and second battery assemblies and the busbar frame. Includes, The busbar frame includes a plurality of holes, A battery pack in which the fire-resistant sheet includes a plurality of cutting guides, each of which overlaps with a corresponding hole among the plurality of holes.

2. Each of the aforementioned plurality of pouch-type battery cells includes a pouch case, a positive electrode lead, and a negative electrode lead. The pouch case includes a first side facing the housing and a second side opposite to the first side. Each of the plurality of pouch-type battery cells is positioned on the second side, and The battery pack according to claim 1, wherein the positive lead and negative lead of each of the plurality of pouch-type battery cells are connected to the corresponding interval busbars from the plurality of interval busbars.

3. The battery pack according to claim 2, wherein the positive lead and negative lead of each of the plurality of pouch-type battery cells are welded to the corresponding interval busbars of the plurality of interval busbars.

4. The battery pack according to claim 2, wherein the negative electrode lead of one of the plurality of pouch-type battery cells is in contact with the upper surface of the corresponding interval bus bar.

5. The busbar frame includes a plurality of read slots, The battery pack according to claim 2, wherein the positive lead and the negative lead of each of the plurality of pouch-type battery cells pass through the corresponding lead slots among the plurality of lead slots.

6. housing, A first to fourth battery assembly disposed on the housing, each of the first to fourth battery assemblies comprising a plurality of pouch-type battery cells, A center beam interposed between the first and second battery assemblies and the third and fourth battery assemblies, In a battery pack comprising busbar assemblies arranged on the first to fourth battery assemblies, The busbar assembly includes a busbar frame covering the first to fourth battery assemblies, and a fireproof sheet interposed between the first to fourth battery assemblies and the busbar frame. The busbar frame includes a plurality of holes, A battery pack in which the fire-resistant sheet includes a plurality of cutting guides, each of which overlaps with a corresponding hole among the plurality of holes.

7. The battery pack according to claim 6, wherein the busbar frame covers the center beam.

8. Each of the aforementioned plurality of pouch-type battery cells includes a pouch case, a positive electrode lead, and a negative electrode lead. The pouch case includes a first side facing the housing and a second side opposite to the first side. The battery pack according to claim 6, wherein the positive lead and the negative lead of each of the plurality of pouch-type battery cells are located on the second side.

9. The busbar assembly includes a plurality of interbusbars arranged on the busbar frame, and The battery pack according to claim 8, wherein the positive lead and negative lead of each of the plurality of pouch-type battery cells are connected to the corresponding interbus bars from among the plurality of interbus bars.

10. The battery pack according to claim 9, wherein the positive lead and negative lead of each of the plurality of pouch-type battery cells are welded to the corresponding of the plurality of interbus bars.

11. The battery pack according to claim 9, wherein the positive electrode lead and the negative electrode lead of any one of the plurality of pouch-type battery cells are separated from each of the plurality of interbus bars.

12. The battery pack according to claim 9, wherein the negative electrode lead of one of the plurality of pouch-type battery cells is in contact with the upper surface of the plurality of busbar frames.

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