Battery pack

Abstract

According to exemplary embodiments, a battery pack is provided. The battery pack comprises: a pack housing including a base plate and side walls; a plurality of battery cell assemblies arranged on the base plate; a plurality of first thermal interface material (TIM) layers interposed between the plurality of battery cell assemblies and the pack housing; a lead coupled to the side walls; and second TIM layers interposed between the lead and the plurality of battery cell assemblies, wherein each of the plurality of battery cell assemblies comprises a plurality of battery cells arranged along a first direction, and a plurality of cooling fins interposed between the plurality of battery cells and having an L-shape.

Description

battery pack

[0001] The present invention relates to a battery pack. This application claims the benefit of Korean Application No. 10-2024-0005409, filed January 12, 2024, which is incorporated herein by reference in its entirety.

[0002] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. They are widely used as a power source for various wireless devices, including handsets, laptops, and cordless vacuum cleaners. Recently, improved energy density and economies of scale have dramatically reduced the per-unit manufacturing cost of secondary batteries. Furthermore, as the range of battery electric vehicles (BEVs) has increased to match that of fuel-powered vehicles, the primary use of secondary batteries is shifting from mobile devices to mobility.

[0003] In the current trend of emphasizing secondary batteries for mobility, the primary direction of secondary battery technology development is to reduce production costs and enhance safety. Secondary batteries account for the largest portion of BEV manufacturing costs. Therefore, the most crucial factor in increasing the market share of BEVs compared to internal combustion engine vehicles is secondary battery production costs. Reducing production costs can be achieved by reducing raw materials, reducing the number of steps in the production process, and shortening takt time. The safety of secondary batteries is crucial, as it directly impacts the lives of vehicle occupants. A key challenge in enhancing secondary battery safety is providing a cooling solution for the battery pack.

[0004] The technical idea of ​​the present invention aims to solve a problem by providing a battery pack with improved cooling efficiency.

[0005] According to exemplary embodiments of the present invention for solving the above-described problem, a battery pack is provided. The battery pack includes a pack housing including a base plate and side walls; a plurality of battery cell assemblies disposed on the base plate; a plurality of first TIM (Thermal Interface Material) layers interposed between the plurality of battery cell assemblies and the pack housing; a lead coupled to the side walls; and second TIM layers interposed between the lead and the plurality of battery cell assemblies, wherein each of the plurality of battery cell assemblies includes a plurality of battery cells arranged along a first direction; and a plurality of cooling fins interposed between the plurality of battery cells and having an L-shape.

[0006] Each of the plurality of cooling fins includes a first portion perpendicular to the first direction and a second portion connected to the first portion and parallel to the first direction.

[0007] The length of the second portion of each of the plurality of cooling fins in the first direction is different from the length of the plurality of battery cells in the first direction.

[0008] The length of the second portion of each of the plurality of cooling fins in the first direction is shorter than the length of the plurality of battery cells in the first direction.

[0009] The length of the second portion of each of the plurality of cooling fins in the first direction is longer than the length of the plurality of battery cells in the first direction.

[0010] The length of the second portion of each of the plurality of cooling fins in the first direction is shorter than twice the length of the plurality of battery cells in the first direction.

[0011] The second TIM layers are in contact with the second portions of the plurality of cooling fins of the plurality of battery cell assemblies and the leads.

[0012] The second portion of the plurality of cooling fins is spaced apart from the lead with the second TIM layers interposed therebetween.

[0013] Each of the plurality of battery cells includes a terrace, which is a sealed portion, and the plurality of cooling fins cover the terrace of a corresponding one of the plurality of battery cells.

[0014] The terraces of each of the plurality of battery cells are spaced apart from the second TIM layers.

[0015] Each of the plurality of cooling fins comprises aluminum or stainless steel.

[0016] Each of the plurality of cooling fins is fixed to a corresponding one of the plurality of battery cells by an adhesive.

[0017] The shape of each of the above plurality of cooling fins is C-shaped.

[0018] Each of the plurality of cooling fins is spaced apart from the base plate.

[0019] Each of the plurality of cooling fins is spaced apart from the first TIM layers.

[0020] According to exemplary embodiments of the present invention, formation of an air layer between TIM layers and battery cells can be prevented by a plurality of cooling fins, and cooling efficiency of the battery pack can be improved.

[0021] The effects that can be obtained from the exemplary embodiments of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure pertain from the following description. In other words, unintended effects resulting from practicing the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure.

[0022] FIG. 1 is a plan view illustrating a battery pack according to exemplary embodiments.

[0023] FIG. 2 is an exploded perspective view of a battery pack according to exemplary embodiments.

[0024] FIG. 3 is a perspective view of a battery cell assembly according to exemplary embodiments.

[0025] Figure 4 is a cross-sectional view taken along the cutting line 3I-3I' of Figure 3.

[0026] Figure 5 is an enlarged partial cross-sectional view of a portion of Figure 4.

[0027] FIG. 6 is a cross-sectional view illustrating a battery cell assembly according to other exemplary embodiments.

[0028] FIG. 7 is a flowchart illustrating a method of assembling a battery pack according to other exemplary embodiments.

[0029] FIG. 8 is a perspective view illustrating a method of assembling a battery pack according to other exemplary embodiments.

[0030] FIG. 9 illustrates a battery cell assembly according to other exemplary embodiments.

[0031] Fig. 10 is a cross-sectional view taken along the cutting line 9I-9I' of Fig. 9.

[0032] Fig. 11 is an enlarged partial cross-sectional view of a portion of Fig. 10.

[0033] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that aligns with the technical spirit of the present invention.

[0034] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0035] In addition, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description is omitted.

[0036] Since the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art, the shapes and sizes of components in the drawings may be exaggerated, omitted, or schematically illustrated for clearer explanation. Accordingly, the sizes and proportions of each component do not fully reflect the actual sizes or proportions.

[0037]

[0038] (Example 1)

[0039] FIG. 1 is a perspective view illustrating a battery pack (100) according to exemplary embodiments.

[0040] FIG. 2 is an exploded perspective view of a battery pack (100) according to exemplary embodiments.

[0041] FIG. 3 is a perspective view of a battery cell assembly (120) according to exemplary embodiments.

[0042] Figure 4 is a cross-sectional view taken along the cutting line 3I-3I' of Figure 3.

[0043] Figure 5 is an enlarged partial cross-sectional view of a portion (POR) of Figure 4.

[0044] Referring to FIGS. 1 to 5, a battery pack (100) may include a housing (110), a plurality of battery cell assemblies (120), first TIM (Thermal Interface Material) layers (131), second TIM layers (133), a gasket (140), a lid (150), a lower injection pipe (161), an upper injection pipe (163), a lower recovery pipe (171), and an upper recovery pipe (173). The battery pack (100) is the final form of a battery system mounted on mobility, etc.

[0045] The housing (110) may provide a space for arranging a plurality of battery cell assemblies (120). The housing (110) may include a base plate (111), side walls (112, 113, 114, 115), and a center beam (116).

[0046] Two directions substantially parallel to the mounting surface of the base plate (111) are defined as the X direction and the Y direction, and a direction substantially perpendicular to the mounting surface of the base plate (111) is defined as the Z direction. Each of the X direction, the Y direction, and the Z direction can be substantially perpendicular to each other. Unless otherwise stated, the definitions of directions are the same for the drawings below.

[0047] The base plate (111) and the side walls (112, 113) may each be provided by an extrusion process. The extrusion direction of the base plate (111) and the side walls (112, 113) may be the X direction. The base plate (111) and the side walls (112, 113) may be arranged in the Y direction. The side walls (114, 115) may also be provided by an extrusion process.

[0048] According to exemplary embodiments, the base plate (111) and side walls (112, 113) may be joined by friction stir welding. The base plate (111) may include a plurality of unit plates joined by friction stir welding.

[0049] The pack housing (110) may include a center beam (116). The center beam (116) may extend in the X direction. The center beam (116) may be interposed between the side walls (112, 113). The center beam (116) may be included in a center plate that is positioned at the center of a plurality of unit plates that are friction stir welded to each other. Accordingly, the center beam (116) may be formed together with the center plate in an extrusion process, and the center beam (116) may be a continuous element integral with the center plate.

[0050] The base plate (111) may include a plurality of cooling channels. The plurality of cooling channels may provide passages for the movement of a coolant, such as water, for example. The plurality of cooling channels may be formed by an extrusion process. The plurality of cooling channels may extend in the X direction. The plurality of cooling channels may be spaced apart in the Y direction.

[0051] The cooling channels of the base plate (111) can be connected to a lower injection pipe (161) and a lower recovery pipe (171). Cooling fluid introduced from the lower injection pipe (161) can flow through the cooling channels and be recovered by the lower recovery pipe (171).

[0052] A plurality of battery cell assemblies (120) may be arranged on a base plate (111) of a housing (110). The base plate (111) may support the plurality of battery cell assemblies (120). Side walls (112, 113, 114, 115) may horizontally surround the plurality of battery cell assemblies (120).

[0053] First TIM layers (131) may be interposed between a plurality of battery cell assemblies (120) and a base plate (111). The first TIM layers (131) may include a resin composition. The first TIM layers (131) may be provided by a thermal resin application process. The first TIM layers (131) may prevent an air layer from being formed between the base plate (111) and the battery cells (121), thereby promoting cooling of the plurality of battery cell assemblies (120). The first TIM layers (131) may be in contact with the plurality of battery cells (121) of the plurality of battery cell assemblies (120) and the base plate (111).

[0054] The resin composition may be a room temperature curable composition. That is, the curing reaction of the resin composition may be initiated and proceed at room temperature. The curing reaction of the resin composition may be accelerated at a temperature higher than room temperature. The curing reaction rate of the resin composition at a temperature higher than room temperature may be faster than the curing reaction rate of the resin composition at room temperature. As a non-limiting example, the subject of the resin composition may be any one of a silicone resin, a polyol resin, an epoxy resin, and an acrylic resin.

[0055] Each of the plurality of battery cell assemblies (120) may include a plurality of battery cells (121), a plurality of pads (122), a first circuit assembly (123), a second circuit assembly (124), a first cross beam (125a), a second cross beam (125b), and a plurality of cooling fins (126).

[0056] Each of the plurality of battery cells (121) may be a lithium ion battery. Each of the plurality of battery cells (121) includes an electrode assembly, an electrolyte, and a case. Each of the plurality of battery cells (121) may be any one of a cylindrical battery cell, a prismatic battery cell, and a pouch-type battery cell. The case of the cylindrical battery cell may be a cylindrical metal can. The electrode assembly of the cylindrical battery cell is housed in the cylindrical metal can. The case of the prismatic battery cell may be a prismatic metal case. The electrode assembly of the prismatic battery cell is housed in the prismatic metal can. The case of the pouch-type battery cell may be a pouch sheet. The electrode assembly of the pouch-type battery cell is housed in a pouch case including an aluminum laminate sheet.

[0057] The electrode assembly may include an anode, a cathode, and a separator interposed between the anode and the cathode. The electrode assembly may be either a jelly-roll type or a stack type. The jelly-roll type electrode assembly may include a winding structure of the anode, the cathode, and the separator interposed therebetween. The stack type electrode assembly may include a plurality of sequentially stacked anodes, a plurality of cathodes, and a plurality of separators interposed therebetween.

[0058] A plurality of battery cells (121) may constitute a plurality of banks. Each of the plurality of banks may include one or more battery cells (121). One or more battery cells (121) of each of the plurality of banks may be connected in parallel with each other. The plurality of banks may be connected in series with each other. The number of series-connected banks and the number of battery cells (121) included in the plurality of banks may be determined according to the magnitude of voltage and current to be output from each of the battery cell assemblies (120).

[0059] A plurality of pads (122) may be interposed between a plurality of battery cells (121). The plurality of pads (122) may horizontally pressurize the plurality of battery cells (121) and absorb a width change in the X direction due to swelling of the plurality of battery cells (121). The plurality of pads (122) may isolate the plurality of battery cells (121) from each other. According to exemplary embodiments, each of the plurality of battery cells (121) may include PU (Poly Urethane). According to exemplary embodiments, each of the plurality of battery cells (121) may include a refractory material such as silicone.

[0060] According to exemplary embodiments, each of the plurality of pads (122) may be arranged alternately with two banks. According to exemplary embodiments, two of the plurality of banks may be interposed between adjacent pads (122). According to other exemplary embodiments, only one bank may be interposed between adjacent pads (122), or three or more banks may be interposed between adjacent pads (122).

[0061] A first integrated circuit assembly (123) and a second integrated circuit assembly (124) may be spaced apart in the Y direction with a plurality of battery cells (121) therebetween. The first integrated circuit assembly (123) may include an insulating frame, an integrated circuit, bus bars, and an insulating cover. The second integrated circuit assembly (124) may include an insulating frame, an integrated circuit, and an insulating cover. The second integrated circuit assembly (124) is generally similar to the first integrated circuit assembly (123) except that it does not include bus bars.

[0062] The insulating frame may include an insulating material such as plastic. The insulating frame may cover the front of a plurality of battery cells (121). The insulating frame may support integrated circuits, bus bars, and sensing plates.

[0063] The bus bars may be short-circuited to the positive leads of one or more battery cells (121) of the first bank and to the negative leads of one or more battery cells (121) of the last bank. The bus bars may be welded to the positive leads of one or more battery cells (121) of the first bank and to the negative leads of one or more battery cells (121) of the last bank. The resulting voltages of the plurality of battery cells (121) may be output through the bus bars. The bus bars may be fixed to an insulating frame.

[0064] The integrated circuit may be mounted on an insulating frame. The positive and negative leads welded together may form nodes within the battery cell assembly (120). The integrated circuit may be configured to measure the voltages of the nodes.

[0065] The insulating cover may include an insulating material, such as plastic. The insulating cover may be fitted into the insulating frame. The insulating cover may cover the integrated circuit, thereby protecting the electrical components of the first integrated circuit assembly (123).

[0066] The first cross beam (125a) and the second cross beam (125b) of each of the battery cell assemblies (120) may be spaced apart from each other with a plurality of battery cells (121) therebetween. The first cross beam (125a) and the second cross beam (125b) may cover the plurality of battery cells (121). The first cross beam (125a) and the second cross beam (125b) may horizontally support the plurality of battery cells (121). The first cross beam (125a) and the second cross beam (125b) may be fixed to the plurality of battery cells (121) by an adhesive material or the like.

[0067] According to exemplary embodiments, the first cross beam (125a) and the second cross beam (125b) may have different and complementary shapes. For example, the second cross beam (125b) of each of the battery cell assemblies (120) may be coupled with the first cross beam (125a) of the subsequent one of the battery cell assemblies (120). For example, the second cross beam (125b) of the battery cell assembly (120) may be coupled with the first cross beam (125a) of the battery cell assembly (120).

[0068] The first cross beam (125a) and the second cross beam (125b) coupled to each other can form a cross beam assembly. The first cross beam (125a) and the second cross beam (125b) of each of the cross beam assemblies can be interlocked with each other. The first cross beam (125a) and the second cross beam (125b) of each of the cross beam assemblies can be in contact with each other. Each of the cross beam assemblies can extend in the Y direction.

[0069] A first cross beam (125a) of a battery cell assembly (120) adjacent to a side wall (114) can be coupled with a supporting beam disposed on a base plate (111). A second cross beam (125b) of a battery cell assembly (120) adjacent to a side wall (115) can be coupled with a supporting beam disposed on the second cross beam (125b). Similarly, a first cross beam (125a) of a battery cell assembly (120) adjacent to a side wall (115) can be coupled with a supporting beam disposed on a base plate (111). A second cross beam (125b) of a battery cell assembly (120) adjacent to a side wall (115) can be coupled with a supporting beam disposed on the second cross beam (125b).

[0070] Each of the plurality of cooling fins (126) may have a high thermal conductivity. Each of the plurality of cooling fins (126) may include a metallic material such as, for example, aluminum and stainless steel.

[0071] Each of the plurality of cooling fins (126) may have an L-shape. The shape of each of the plurality of cooling fins (126) may be different from a C-shape. Each of the plurality of cooling fins (126) may include a first portion (126V) substantially perpendicular to the X-direction and a second portion (126H) substantially parallel to the X-direction. The second portion (126H) may be connected to the first portion (126V). The first portion (126V) of each of the plurality of cooling fins (126) may be substantially parallel to the Z-direction. The second portion (126H) of each of the plurality of cooling fins (126) may be substantially perpendicular to the Z-direction.

[0072] The second portion (126H) and the first portion (126V) may extend in the Y direction. The second portion (126H) of each of the plurality of cooling fins (126) may guide high-temperature gases and flames discharged from the plurality of battery cells (121) in the Y direction in a thermal runaway event. Accordingly, a thermal runaway event occurring in one of the plurality of battery cells (121) may be prevented from spreading to other battery cells (121), and the safety of the battery pack (100) may be improved.

[0073] Each of the plurality of cooling fins (126) may be spaced apart from the first TIM layers (131) interposed between the plurality of battery cells (121) and the base plate (111). Each of the plurality of cooling fins (126) may be spaced apart from the base plate (111). Each of the plurality of cooling fins (126) may not include a portion interposed between the plurality of battery cells (121) and the base plate (111).

[0074] The length of the second part (126H) of each of the plurality of cooling fins (126) in the X direction may be different from the length of each of the plurality of battery cells (121) in the X direction. The length of the second part (126H) of each of the plurality of cooling fins (126) in the X direction may be shorter than the length of each of the plurality of battery cells (121) in the X direction. Accordingly, when the plurality of battery cells (121) are coupled to each other, interference between the plurality of cooling fins (126) can be prevented.

[0075] The length of the first portion (126V) of each of the plurality of cooling fins (126) in the Z direction may be different from the length of each of the plurality of battery cells (121) in the Z direction. The length of the first portion (126V) of each of the plurality of cooling fins (126) in the Z direction may be longer than the length of each of the plurality of battery cells (121) in the Z direction, but is not limited thereto. The length of the first portion (126V) of each of the plurality of cooling fins (126) in the Z direction may be equal to the length of each of the plurality of battery cells (121) in the Z direction, or may be shorter than the length of each of the plurality of battery cells (121) in the Z direction.

[0076] A plurality of cooling fins (126) may be interposed between a plurality of battery cells (121). A first portion (126V) of each of the plurality of cooling fins (126) may be interposed between the plurality of battery cells (121). Each of the plurality of cooling fins (126) may be coupled to a corresponding one of the plurality of battery cells (121). According to exemplary embodiments, the plurality of battery cells (121) and the plurality of cooling fins (126) may correspond one-to-one.

[0077] According to exemplary embodiments, one of the plurality of cooling fins (126) may be interposed between two adjacent ones of the plurality of battery cells (121). According to exemplary embodiments, one of the plurality of battery cells (121) may be interposed between two adjacent ones of the plurality of cooling fins (126).

[0078] A plurality of cooling fins (126) may be coupled to a plurality of battery cells (121). The plurality of cooling fins (126) may be coupled to the plurality of battery cells (121), for example, by an adhesive. The adhesive may be applied between a first portion (126V) of each of the plurality of cooling fins (126) and the plurality of battery cells (121).

[0079] A second portion (126H) of each of the plurality of cooling fins (126) may be spaced apart from the plurality of battery cells (121). The second portion (126H) of each of the plurality of cooling fins (126) may cover a terrace (121T) of a corresponding one of the plurality of battery cells (121). The terrace (121T) of the plurality of battery cells (121) may be spaced apart from the second TIM layers (133). The terrace (121T) of each of the plurality of battery cells (121) may be isolated from the second TIM layers (133) by the plurality of cooling fins (126). Here, the terrace (121T) may be a sealed portion of a pouch case of each of the plurality of battery cells (121). The terrace (121T) may be fixed to a receiving portion of the pouch case by a folding tape.

[0080] The center beam (116) can extend in the X direction. The center beam (116) can overlap the center of the base plate. The center beam (116) can isolate the battery cell assemblies (120) from each other. The center beam (116) can be interposed between the battery cell assemblies (120).

[0081] In this example, the plurality of battery cell assemblies (120) are arranged in two rows and three columns. Accordingly, the plurality of battery cell assemblies (120) can be said to be arranged in a 3 * 2 configuration. A person skilled in the art will easily arrive at a battery pack including a plurality of battery cell assemblies (120) arranged in an M * N configuration based on the description herein. Here, M and N are each any integer greater than or equal to 2.

[0082] The lid (150) may be coupled to the side walls (112, 113, 114, 115). The lid (150) may be fixed to the side walls (112, 113, 114, 115) by mechanical means such as bolts. The lid (150) may cover elements disposed inside the battery pack (100), such as battery cell assemblies (120) and electrical components. A gasket (140) may be interposed between the lid (150) and the side walls (112, 113, 114, 115). The gasket may provide a liquid-tight seal to the battery pack (100).

[0083] According to exemplary embodiments, the lid (150) may be provided by an extrusion process. The lid (150) may include a plurality of cooling channels. The plurality of cooling channels may provide passages for the movement of a coolant, such as water, for example. The plurality of cooling channels may be formed by an extrusion process. The plurality of cooling channels may extend in the X direction. The plurality of cooling channels may be spaced apart in the Y direction.

[0084] The cooling channels of the lead (150) can be connected to an upper injection pipe (163) and an upper return pipe (173). Cooling fluid introduced from the upper injection pipe (163) can flow through the cooling channels and be recovered by the upper return pipe (173).

[0085] Second TIM layers (133) may be interposed between the lead (150) and the battery cell assemblies (120). The second TIM layers (133) may be thermal transfer pads. Each of the second TIM layers (133) may be spaced apart from the plurality of battery cells (121). Each of the second TIM layers (133) may be in contact with the plurality of cooling fins (126). Each of the second TIM layers (133) may be in contact with the second portion (126V) of the plurality of cooling fins (126). Each of the second TIM layers (133) may be in contact with the lead (150). The second portion (126H) of each of the plurality of cooling fins (126) may be spaced apart from the lead (150) with the second TIM layers (133) therebetween.

[0086] A conventional cooling solution covers a plurality of battery cells (121) with a second TIM layer (133). At this time, due to the terraces (121T) of the plurality of battery cells (121), an air layer may be formed between the plurality of battery cells (121) and the second TIM layer (133), and the cooling efficiency of the plurality of battery cells (121) may be reduced.

[0087] According to exemplary embodiments, a plurality of cooling fins (126) are provided that come into contact with a plurality of battery cells (121) and cover terrace portions (121T) of the plurality of battery cells (121), so that each of the cooling channels of the base plate (111) and the cooling channels of the lead (150) can be efficiently used, and the cooling efficiency of the battery pack (100) can be improved. Furthermore, the lower portion of each of the plurality of battery cells (121) directly comes into contact with the first TIM layers (131), so that the cooling efficiency of the battery pack (100) can be further improved.

[0088] The battery pack (100) may further include exhaust devices coupled to the sidewall (115). The exhaust devices may delay heat propagation by exhausting high temperature gases and flames inside the battery pack (100) when a thermal runaway event occurs within the battery pack (100).

[0089] Here, thermal runaway of multiple battery cell assemblies (120) is a state in which temperature changes of multiple battery cell assemblies (120) further accelerate the temperature change, which is an uncontrollable positive feedback. Multiple battery cell assemblies (120) in a state of thermal runaway exhibit a rapid temperature increase and emit a large amount of high-pressure gas and combustion debris.

[0090] The battery pack (100) may further include electrical components. The electrical components may include any electronic components necessary to operate the battery pack. The electrical components may be positioned on an electrical component mounting area (EMR).

[0091] The electrical components may include, for example, a Battery Management System (BMS). The BMS may be configured to monitor, balance, and control the battery pack. Monitoring of the battery pack (100) may include measuring voltage and current of specific nodes within a plurality of battery cell assemblies (120) and measuring temperature of set locations within the battery pack (100). The battery pack (100) may include measuring instruments for measuring the voltage, current, and temperature described above.

[0092] Balancing of a battery pack (100) is an operation that reduces the deviation between multiple battery cell assemblies (120). Control of the battery pack (100) includes preventing overcharge, overdischarge, 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 cell assemblies (120).

[0093] The electrical components may further include a cooling device, a PRA (Power Relay Assembly), a safety plug, etc. The cooling device may include a cooling fan. The cooling fan may prevent overheating of each of the plurality of battery cell assemblies (120) 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., a vehicle motor). The PRA may protect the plurality of battery cell assemblies (120) and the external load (e.g., a vehicle motor) by cutting off power supply to the external load (e.g., a vehicle motor) in a situation where an abnormal voltage, such as a voltage surge, occurs.

[0094] The battery pack (100) may further include a plurality of exhaust devices. The plurality of exhaust devices may be installed in any one of the lid (150) and the side walls (112, 113, 114, 115). The plurality of exhaust devices may provide a path for discharging high-temperature gases inside the battery pack (100) to the outside when a thermal runaway event occurs in some of the battery cell assemblies (120). Accordingly, thermal propagation may be delayed, and the stability of the battery pack (100) may be improved.

[0095]

[0096] (Example 2)

[0097] Fig. 6 is a cross-sectional view illustrating a battery cell assembly (120') according to other exemplary embodiments. More specifically, Fig. 6 shows a portion corresponding to Fig. 5. The battery cell assembly (120') can replace the battery cell assembly (120) of Fig. 3.

[0098] Referring to FIG. 6, a battery cell assembly (120') may include a plurality of battery cells (121), a plurality of pads (122), a first circuit assembly (123, see FIG. 3), a second circuit assembly (124, see FIG. 3), a first cross beam (125a, see FIG. 3), a second cross beam (125b, see FIG. 3), and a plurality of cooling fins (127).

[0099] The plurality of battery cells (121), the plurality of pads (122), the first circuit assembly (123, see FIG. 3), the second circuit assembly (124, see FIG. 3), the first cross beam (125a, see FIG. 3), and the second cross beam (125b, see FIG. 3) are substantially the same as those described with reference to FIGS. 1 to 5, and therefore, a duplicate description thereof will be omitted.

[0100] Each of the plurality of cooling fins (127) may have high thermal conductivity. Each of the plurality of cooling fins (127) may include a metal material such as, for example, aluminum and stainless steel.

[0101] Each of the plurality of cooling fins (127) may have an L-shape. The shape of each of the plurality of cooling fins (127) may be different from a C-shape. Each of the plurality of cooling fins (127) may include a first portion (127V) substantially parallel to the Z-direction and a second portion (127H) substantially perpendicular to the Z-direction. Each of the plurality of cooling fins (127) may be spaced apart from the first TIM layers (131, see FIG. 2) interposed between the plurality of battery cells (121) and the base plate (111, see FIG. 2). Each of the plurality of cooling fins (127) may not include a portion interposed between the plurality of battery cells (121) and the base plate (111, see FIG. 2).

[0102] The length of the second part (127H) of each of the plurality of cooling fins (127) in the X direction may be different from the length of each of the plurality of battery cells (121) in the X direction. The length of the second part (127H) of each of the plurality of cooling fins (127) in the X direction may be longer than the length of each of the plurality of battery cells (121) in the X direction. Accordingly, the second part (127H) of each of the plurality of cooling fins (127) may cover two or more battery cells (121). The length of the second part (127H) of each of the plurality of cooling fins (127) in the X direction may be smaller than N times the length of each of the battery cells (121) in the X direction (wherein N is the number of battery cells (121) covered by each of the plurality of cooling fins (127). Accordingly, when the plurality of battery cells (121) are coupled to each other, interference between the plurality of cooling fins (127) may be prevented.

[0103] For example, as in the example of FIG. 6, when the second part (127H) of each of the plurality of cooling fins (127) covers two battery cells (121), the length in the X direction of the second part (127H) of each of the plurality of cooling fins (127) may be less than twice the length in the X direction of each of the battery cells (121).

[0104] The length of the first portion (127V) of each of the plurality of cooling fins (127) in the Z direction may be different from the length of each of the plurality of battery cells (121) in the Z direction. The length of the first portion (127V) of each of the plurality of cooling fins (127) in the Z direction may be longer than the length of each of the plurality of battery cells (121) in the Z direction, but is not limited thereto. The length of the first portion (127V) of each of the plurality of cooling fins (127) in the Z direction may be equal to the length of each of the plurality of battery cells (121) in the Z direction, or may be shorter than the length of each of the plurality of battery cells (121) in the Z direction.

[0105] A plurality of cooling fins (127) may be interposed between a plurality of battery cells (121). A first portion (127V) of each of the plurality of cooling fins (127) may be interposed between the plurality of battery cells (121). Each of the plurality of cooling fins (127) may be coupled to a corresponding one of the plurality of battery cells (121). According to exemplary embodiments, the plurality of battery cells (121) and the plurality of cooling fins (127) may correspond in a many-to-one (e.g., two-to-one) ratio.

[0106] According to exemplary embodiments, one of the plurality of cooling fins (127) may be interposed between two adjacent ones of the plurality of battery cells (121). According to exemplary embodiments, two or more of the plurality of battery cells (121) may be interposed between two adjacent ones of the plurality of cooling fins (127).

[0107] According to exemplary embodiments, the plurality of cooling fins (127) may be in contact with two of the plurality of battery cells (121). Accordingly, the energy density of the battery cell assembly (120') may be increased compared to a case where the plurality of cooling fins (127) are coupled to each of the plurality of battery cells (121).

[0108] A plurality of cooling fins (127) may be coupled to a plurality of battery cells (121). The plurality of cooling fins (127) may be coupled to the plurality of battery cells (121), for example, by an adhesive. The adhesive may be applied between a first portion (127V) of each of the plurality of cooling fins (127) and the plurality of battery cells (121).

[0109] The second portion (127H) of each of the plurality of cooling fins (127) may be spaced apart from the plurality of battery cells (121). The second portion (127H) of each of the plurality of cooling fins (127) may cover a terrace (121T) of a corresponding one of the plurality of battery cells (121). The second portion (127H) of each of the plurality of cooling fins (127) may cover two or more terraces (121T) of the plurality of battery cells (121).

[0110]

[0111] (Example 3)

[0112] FIG. 7 is a flowchart illustrating a method of assembling a battery pack (100) according to other exemplary embodiments.

[0113] FIG. 8 is a perspective view illustrating a method of assembling a battery pack (100) according to other exemplary embodiments.

[0114] Referring to FIGS. 2 and 7, a pack housing (110) may be provided at P110. Providing the pack housing (110) may include applying first TIM layers (131) on the pack housing (110).

[0115] Next, referring to FIGS. 2, 7, and 8, a plurality of battery cell assemblies (120) may be arranged on the pack housing (110). In order to arrange the plurality of battery cell assemblies (120) on the pack housing (110), as illustrated in FIG. 8, first portions (AP1) and second portions (AP2) of the plurality of cooling fins (126) may be adsorbed. According to exemplary embodiments, the plurality of cooling fins (126) have relatively high rigidity and may be used to transport the plurality of battery cell assemblies (120) using adsorption. Furthermore, since a uniform force is applied to the plurality of battery cells (121) of each of the plurality of battery cell assemblies (120) while each of the plurality of battery cell assemblies (120) is being transported, the plurality of battery cells (121) may be prevented from being damaged during the assembly process of the battery pack (100).

[0116] Next, referring to FIGS. 1 and 7, the pack housing (110) and the lead (150) can be joined at P130. The pack housing (110) and the lead (150) can be joined by a mechanical method such as bolting.

[0117]

[0118] (Example 4)

[0119] FIG. 9 illustrates a battery cell assembly (120") according to other exemplary embodiments.

[0120] Fig. 10 is a cross-sectional view taken along the cutting line 9I-9I' of Fig. 9.

[0121] Fig. 11 is an enlarged partial cross-sectional view of a portion (POR') of Fig. 10.

[0122] Referring to FIGS. 9 to 11, each of the plurality of battery cell assemblies (120) may include a plurality of battery cells (121), a plurality of pads (122), a first circuit assembly (123), a second circuit assembly (124), a first cross beam (125a, see FIG. 3), a second cross beam (125b, see FIG. 3), and a plurality of cooling fins (126, 126').

[0123] The plurality of battery cells (121), the plurality of pads (122), the first circuit assembly (123), the second circuit assembly (124), the first cross beam (125a, see FIG. 3), the second cross beam (125b, see FIG. 3), and the plurality of cooling fins (126) are substantially the same as those described with reference to FIGS. 1 to 5, and therefore, a duplicate description thereof will be omitted.

[0124] A plurality of cooling fins (126') may be arranged at the edge in the X direction. Each of the plurality of cooling fins (126') may include a pin hole (126PH). The pin hole (126PH) of each of the plurality of cooling fins (126') may partially expose an adjacent one of the plurality of battery cells (121).

[0125] When the battery cell assembly (120") is placed on the pack housing (110) in P120 of FIG. 7, the pin hole (126PH) of each of the plurality of cooling fins (126') can be used. The pin hole (126PH) of each of the plurality of cooling fins (126') can be used for transporting the battery cell assembly (120"). More specifically, a lifting jig can be inserted into the plurality of cooling fins (126') through the pin hole (126PH) of each of the plurality of cooling fins (126'), and the battery cell assembly (120") can be transported.

[0126]

[0127] The present invention has been described in more detail through drawings and examples. However, the configurations described in the drawings or examples described in this specification are merely embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that various equivalents and modified examples may exist as of the time of this application.

Claims

1. Pack housing including base plate and side walls; A plurality of battery cell assemblies arranged on the base plate; A plurality of first TIM (Thermal Interface Material) layers interposed between the plurality of battery cell assemblies and the pack housing; leads coupled to the side walls; and Including second TIM layers interposed between the lead and the plurality of battery cell assemblies, Each of the above plurality of battery cell assemblies, A plurality of battery cells arranged along a first direction; and A battery pack characterized by including a plurality of cooling fins having an L shape and interposed between the plurality of battery cells.

2. In paragraph 1, A battery pack, characterized in that each of the plurality of cooling fins includes a first portion perpendicular to the first direction and a second portion connected to the first portion and parallel to the first direction.

3. In paragraph 2, A battery pack, characterized in that the length of the second portion of each of the plurality of cooling fins in the first direction is different from the length of the plurality of battery cells in the first direction.

4. In paragraph 2, A battery pack, characterized in that the length of the second portion of each of the plurality of cooling fins in the first direction is shorter than the length of the plurality of battery cells in the first direction.

5. In paragraph 2, A battery pack, characterized in that the length of the second portion of each of the plurality of cooling fins in the first direction is longer than the length of the plurality of battery cells in the first direction.

6. In paragraph 2, A battery pack, characterized in that the length of the second portion of each of the plurality of cooling fins in the first direction is shorter than twice the length of the plurality of battery cells in the first direction.

7. In paragraph 2, A battery pack, wherein the second TIM layers are in contact with the second portions of the plurality of cooling fins of the plurality of battery cell assemblies and the leads.

8. In paragraph 7, A battery pack, characterized in that the second portion of the plurality of cooling fins is spaced apart from the lead with the second TIM layers interposed therebetween.

9. In paragraph 7, Each of the plurality of battery cells includes a terrace, which is a sealed portion, and A battery pack, characterized in that the plurality of cooling fins cover the terrace of a corresponding one of the plurality of battery cells.

10. In paragraph 9, A battery pack, wherein each of the plurality of battery cells has a terrace spaced apart from the second TIM layers.

11. In paragraph 1, A battery pack, wherein each of the plurality of cooling fins comprises aluminum or stainless steel.

12. In paragraph 1, A battery pack, characterized in that each of the plurality of cooling fins is fixed to a corresponding one of the plurality of battery cells by an adhesive.

13. In paragraph 1, A battery pack characterized in that each of the plurality of cooling fins has a different shape from the letter C.

14. In paragraph 1, A battery pack, wherein each of the plurality of cooling fins is spaced apart from the base plate.

15. In paragraph 1, A battery pack, wherein each of said plurality of cooling fins is spaced apart from said first TIM layers.

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