Battery pack

Abstract

According to exemplary embodiments, a battery pack is provided. The battery pack comprises: a pack housing comprising a base plate and sidewalls; first to third battery cell assemblies on the base plate, the first to third battery cell assemblies each comprising multiple battery cells arranged in a first direction; a heat blocking pad between the first and second battery cell assemblies; and a first partition wall between the second and third battery cell assemblies.

Description

battery pack

[0001] The present invention relates to a battery pack. This application claims the benefit of Korean Application No. 10-2024-0080281, filed June 20, 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] As secondary batteries become increasingly used in mobility, demand for their safety is increasing. Accidents such as fires in secondary batteries used in mobility vehicles can endanger the lives of drivers, making research into technologies that enhance the safety of secondary batteries essential.

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

[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; first to third battery cell assemblies on the base plate, each of the first to third battery cell assemblies including a plurality of battery cells arranged in a first direction; and; a heat blocking pad between the first and second battery cell assemblies; and a first partition wall between the second and third battery cell assemblies.

[0006] The length of the second direction perpendicular to the first direction of the heat blocking pad is different from the length of each of the first and second battery cell assemblies in the second direction.

[0007] The length of the second direction perpendicular to the first direction of the heat blocking pad is greater than the length of each of the first and second battery cell assemblies in the second direction.

[0008] The above heat blocking pad is spaced apart from the first bulkhead with the second battery cell assembly therebetween.

[0009] Each of the first to third battery cell assemblies includes a frame assembly surrounding the plurality of battery cells and a flame cover coupled to the frame assembly.

[0010] The above frame assembly comprises a U-frame and a top plate welded together.

[0011] The above heat blocking pad is in contact with the flame cover of each of the first and second battery cells.

[0012] The above heat blocking pad includes a pad case, heat diffusion layers within the pad case, and a heat absorbing material.

[0013] The above heat diffusion layers are spaced apart with the heat absorbing material therebetween.

[0014] Each of the above heat spreading layers comprises a metal.

[0015] The above heat absorbing material includes water and a superabsorbent resin.

[0016] Each of the battery cells of the first to third battery cell assemblies includes a cell case, and the cell case includes the same material as the pad case.

[0017] The above heat blocking pad has a dog bone shape.

[0018] The above heat blocking pad has a dumbbell shape.

[0019] According to exemplary embodiments of the present invention, an inter-module pad comprising a case, a thermally conductive layer, and a super absorbent polymer (SAP) may be provided between modules. The inter-module pad may be applied to narrow spaces where cross beams cannot enter, and may enhance the safety of the battery pack by blocking heat transfer between modules.

[0020] 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.

[0021] FIG. 1 is a plan view of a battery pack according to exemplary embodiments.

[0022] FIG. 2 is a perspective view of a battery cell assembly according to exemplary embodiments.

[0023] FIG. 3 is an exploded perspective view of a battery cell assembly according to exemplary embodiments.

[0024] FIG. 4 is a flowchart illustrating a method for manufacturing a battery pack according to exemplary embodiments.

[0025] FIG. 5 is a perspective view illustrating a method of manufacturing a battery pack according to exemplary embodiments.

[0026] FIG. 6 is a plan view illustrating a method of manufacturing a battery pack according to exemplary embodiments.

[0027] Figure 7 is a side view of a heat blocking pad according to exemplary embodiments.

[0028] Figure 8 is a cross-sectional view of a heat blocking pad according to exemplary embodiments.

[0029] FIG. 9 is a perspective view illustrating a method of manufacturing a battery pack according to exemplary embodiments.

[0030] FIG. 10 is a plan view illustrating a method of manufacturing a battery pack according to exemplary embodiments.

[0031] 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 concept of a term to best explain his or her invention, they should be construed as meanings and concepts consistent with the technical spirit of the present invention.

[0032] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention, and it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0033] 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.

[0034] 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.

[0035]

[0036] (Example 1)

[0037] FIG. 1 is a plan view of a battery pack (100) according to exemplary embodiments.

[0038] Referring to FIG. 1, a battery pack (100) may include a pack housing (110), a plurality of battery cell assemblies (120_1 to 120_13, 120_5, 120_6, 120_7, 120_8, 120_9, 120_10, 120_11, 120_12, 120_13, hereinafter, 120_1 to 120_13), first bulkheads (131), second bulkheads (133), third bulkheads (135), fourth bulkheads (137), fifth bulkheads (139), and heat blocking pads (140_1, 140_2, 140_3, 140_4). The battery pack (100) may be a final product mounted in an application such as a vehicle.

[0039] The pack housing (110) can provide a space for mounting battery cell assemblies (120_1 to 120_13). The pack housing (110) can include a base plate (111) and side walls (112, 113, 114, 115).

[0040] The base plate (111) and the side walls (112, 113) may each be provided by an extrusion process. The side walls (114, 115) may also be provided by an extrusion process. The side walls (112, 113, 114, 115) may be substantially perpendicular to the base plate (111).

[0041] 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.

[0042] Two directions substantially parallel to the upper surface of the base plate (111) are defined as the X direction and the Y direction, and a direction substantially perpendicular to the upper surface of the base plate (111) is defined as the Z direction. The X direction, the Y direction, and the Z direction can be substantially perpendicular.

[0043] 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.

[0044] A plurality of battery cell assemblies (120_1 to 120_13) may be arranged on a base plate (111) of a pack housing (110). The base plate (111) may support the plurality of battery cell assemblies (120_1 to 120_13). Side walls (112, 113, 114, 115) may horizontally surround the plurality of battery cell assemblies (120_1 to 120_13).

[0045] Battery cell assemblies (120_1, 120_2, 120_3, 120_4, 120_5, hereinafter, 120_1 to 120_5) may be arranged in the Y direction. Battery cell assemblies (120_1 to 120_5) may be arranged sequentially in the Y direction. Battery cell assembly (120_2) may be interposed between battery cell assemblies (120_1, 120_3). Battery cell assembly (120_3) may be interposed between battery cell assemblies (120_2, 120_4). Battery cell assembly (120_4) may be interposed between battery cell assemblies (120_3, 120_5). Battery cell assemblies (120_1, 120_5) can be spaced apart from each other with battery cell assemblies (120_2, 120_3, 120_4) interposed therebetween.

[0046]

[0047] Battery cell assemblies (120_6, 120_7, 120_8, 120_9, hereinafter, 120_6 to 120_9) may be arranged in the X direction. Battery cell assemblies (120_6 to 120_9) may be arranged in order in the X direction. Battery cell assembly (120_7) may be interposed between battery cell assemblies (120_6, 120_8). Battery cell assembly (120_8) may be interposed between battery cell assemblies (120_7, 120_9). Battery cell assemblies (120_6, 120_9) may be spaced apart from each other with battery cell assemblies (120_7, 120_8) interposed therebetween.

[0048]

[0049] Battery cell assemblies (120_10, 120_11, 120_12, 120_13, hereinafter, 120_10 to 120_13) may be arranged in the X direction. Battery cell assemblies (120_10 to 120_13) may be arranged in order in the X direction. Battery cell assembly (120_11) may be interposed between battery cell assemblies (120_10, 120_12). Battery cell assembly (120_12) may be interposed between battery cell assemblies (120_11, 120_13). Battery cell assemblies (120_10, 120_13) may be spaced apart from each other with battery cell assemblies (120_11, 120_12) interposed therebetween.

[0050]

[0051] Each of the first bulkheads (131), the second bulkhead (133), the third bulkhead (135), the fourth bulkheads (137), and the fifth bulkheads (139) may be on the base plate (111). Each of the first bulkheads (131), the second bulkhead (133), the third bulkhead (135), the fourth bulkheads (137), and the fifth bulkheads (139) may be provided as an integral part of parts of the base plate (111) by an extrusion process, or may be welded to the base plate (111).

[0052] Each of the first bulkheads (131) and the second bulkhead (133) may be substantially parallel to each of the side walls (112, 113). Each of the first bulkheads (131) and the second bulkhead (133) may be interposed between the side walls (112, 113).

[0053] Each of the third bulkhead (135), the fourth bulkheads (137), and the fifth bulkheads (139) may be substantially parallel to each of the side walls (114, 115). Each of the third bulkhead (135), the fourth bulkheads (137), and the fifth bulkheads (139) may be interposed between the side walls (114, 115).

[0054] Each of the first bulkheads (131) and the second bulkheads (133) may extend in the X direction. One of the first bulkheads (131) may be interposed between the battery cell assemblies (120_2, 120_3). One of the first bulkheads (131) may isolate the battery cell assemblies (120_2, 120_3) in the Y direction. Another of the first bulkheads (131) may be interposed between the battery cell assemblies (120_3, 120_4). Another of the first bulkheads (131) may isolate the battery cell assemblies (120_3, 120_4) in the Y direction. The second bulkhead (133) may be interposed between the battery cell assemblies (120_6 to 120_9) and the battery cell assemblies (120_10 to 120_13). The second bulkhead (133) can isolate the battery cell assemblies (120_6 to 120_9) and the battery cell assemblies (120_10 to 120_13) in the Y direction.

[0055] There may be no heat blocking pad between the battery cell assemblies (120_2, 120_3). There may be no heat blocking pad between the battery cell assemblies (120_3, 120_4). There may be no heat blocking pad between the battery cell assemblies (120_6, 120_7, 120_8, 120_9) and the battery cell assemblies (120_10, 120_11, 120_12, 120_13). Each of the heat blocking pads (140_1, 140_2, 140_3, 140_4) may be spaced apart from each of the first and second bulkheads (131, 133).

[0056] Each of the third bulkhead (135), the fourth bulkheads (137), and the fifth bulkheads (139) may extend in the Y direction. The third bulkhead (135) may be interposed between the battery cell assemblies (120_1 to 120_5) and the battery cell assemblies (120_6, 120_7, 120_8, 120_9, 120_10, 120_11, 120_12, 120_13, hereinafter, 120_6 to 120_13). The third bulkhead (135) may isolate the battery cell assemblies (120_1 to 120_5) and the battery cell assemblies (120_6 to 120_13) in the X direction.

[0057] The fourth bulkheads (137) may overlap each other in the Y direction. A second bulkhead (133) may be between the fourth bulkheads (137). One of the fourth bulkheads (137) may be interposed between the battery cell assemblies (120_7, 120_8). One of the fourth bulkheads (137) may isolate the battery cell assemblies (120_7, 120_8) in the Y direction. Another of the fourth bulkheads (137) may be interposed between the battery cell assemblies (120_11, 120_12). Another of the fourth bulkheads (137) may isolate the battery cell assemblies (120_11, 120_12) in the Y direction.

[0058] The fifth bulkheads (139) may overlap each other in the Y direction. A second bulkhead (133) may be present between the fifth bulkheads (139). One of the fifth bulkheads (139) may be interposed between the battery cell assemblies (120_8, 120_9). One of the fifth bulkheads (139) may isolate the battery cell assemblies (120_8, 120_9) in the Y direction. Another of the fifth bulkheads (139) may be interposed between the battery cell assemblies (120_10, 120_11). Another of the fifth bulkheads (139) may isolate the battery cell assemblies (120_10, 120_11) in the Y direction.

[0059] There may be no heat blocking pad between the battery cell assemblies (120_1 to 120_5) and the battery cell assemblies (120_6 to 120_13). There may be no heat blocking pad between the battery cell assemblies (120_7, 120_8). There may be no heat blocking pad between the battery cell assemblies (120_8, 120_9). There may be no heat blocking pad between the battery cell assemblies (120_6 to 120_9) and the battery cell assemblies (120_10 to 120_13). There may be no heat blocking pad between the battery cell assemblies (120_10, 120_11). There may be no heat blocking pad between the battery cell assemblies (120_11, 120_12). Each of the heat blocking pads (140_3, 140_4) may be spaced apart from the third bulkhead (135). Each of the heat blocking pads (140_1, 140_2, 140_3, 140_4) may be spaced apart from each of the fourth and fifth bulkheads (137, 139).

[0060]

[0061] The heat blocking pads (140_1, 140_2, 140_3, 140_4) may be located in a space between the plurality of battery cell assemblies (120_1 to 120_13) that is not wide enough to accommodate the first to fifth bulkheads (131, 133, 135, 137, 139).

[0062] A heat blocking pad (140_1) may be interposed between the battery cell assemblies (120_1, 120_2). The heat blocking pad (140_1) may isolate the battery cell assemblies (120_1, 120_2) in the Y direction. The heat blocking pad (140_1) may be in contact with each of the battery cell assemblies (120_1, 120_2). The heat blocking pad (140_1) may be in contact with the flame cover (129, see FIG. 3) of each of the battery cell assemblies (120_1, 120_2).

[0063] A heat blocking pad (140_2) may be interposed between the battery cell assemblies (120_4, 120_5). The heat blocking pad (140_2) may isolate the battery cell assemblies (120_4, 120_5) in the Y direction. The heat blocking pad (140_2) may be in contact with each of the battery cell assemblies (120_4, 120_5). The heat blocking pad (140_2) may be in contact with the flame cover (129, see FIG. 3) of each of the battery cell assemblies (120_4, 120_5).

[0064] A heat blocking pad (140_3) may be interposed between the battery cell assemblies (120_6, 120_7). The heat blocking pad (140_3) may isolate the battery cell assemblies (120_6, 120_7) in the X direction. The heat blocking pad (140_3) may be in contact with each of the battery cell assemblies (120_6, 120_7). The heat blocking pad (140_3) may be in contact with the flame cover (129, see FIG. 3) of each of the battery cell assemblies (120_6, 120_7).

[0065] A heat blocking pad (140_4) may be interposed between the battery cell assemblies (120_12, 120_13). The heat blocking pad (140_4) may isolate the battery cell assemblies (120_12, 120_13) in the X direction. The heat blocking pad (140_4) may be in contact with each of the battery cell assemblies (120_12, 120_13). The heat blocking pad (140_4) may be in contact with the flame cover (129, see FIG. 3) of each of the battery cell assemblies (120_12, 120_13).

[0066] Accordingly, neighboring ones of the battery cell assemblies (120_1 to 120_13) can be isolated by one of the first to fifth bulkheads (131, 133, 135, 137, 139) and the heat blocking pads (140_1, 140_2, 140_3, 140_4), and heat transfer between neighboring ones of the battery cell assemblies (120_1 to 120_13) can be prevented, so that the safety of the battery pack (100) can be improved.

[0067] The length (e.g., length in the X direction) of the heat blocking pad (140_1) may be different from the length (e.g., length in the X direction) of each of the battery cell assemblies (120_1, 120_2). The length (e.g., length in the X direction) of the heat blocking pad (140_1) may be greater than the length (e.g., length in the X direction) of each of the battery cell assemblies (120_1, 120_2).

[0068] The length (e.g., length in the X direction) of the heat blocking pad (140_2) may be different from the length (e.g., length in the X direction) of each of the battery cell assemblies (120_4, 120_5). The length (e.g., length in the X direction) of the heat blocking pad (140_2) may be greater than the length (e.g., length in the X direction) of each of the battery cell assemblies (120_4, 120_5).

[0069] The length (e.g., length in the Y direction) of the heat blocking pad (140_3) may be different from the length (e.g., length in the Y direction) of each of the battery cell assemblies (120_6, 120_7). The length (e.g., length in the Y direction) of the heat blocking pad (140_3) may be greater than the length (e.g., length in the Y direction) of each of the battery cell assemblies (120_6, 120_7).

[0070] The length (e.g., length in the Y direction) of the heat blocking pad (140_4) may be different from the length (e.g., length in the Y direction) of each of the battery cell assemblies (120_12, 120_13). The length (e.g., length in the Y direction) of the heat blocking pad (140_4) may be greater than the length (e.g., length in the Y direction) of each of the battery cell assemblies (120_12, 120_13).

[0071] The battery pack (100) may further include a Battery Management System (BMS). The BMS may be configured to perform monitoring, balancing, and control of the battery pack (100). Monitoring of the battery pack (100) may include measuring voltage and current of specific nodes within a plurality of battery cell assemblies (120_1 to 120_13) and measuring temperatures of set locations within the battery pack (100).

[0072] Balancing of the battery pack (100) is an operation to reduce the deviation between the plurality of battery cell assemblies (120_1 to 120_13). Control of the battery pack (100) includes preventing the occurrence of 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 plurality of battery cell assemblies (120_1 to 120_13).

[0073] The battery pack may further include exhaust devices coupled to the side walls (114, 115). Either of the side walls (114, 115) may include exhaust holes connected to the exhaust devices. The exhaust devices may be configured to delay thermal propagation by releasing high-temperature gas within the battery pack (100) to the outside when a thermal runway event occurs in a plurality of battery cell assemblies (120_1 to 120_13).

[0074] Here, thermal runaway of multiple battery cell assemblies (120_1 to 120_13) is a state in which temperature changes of multiple battery cell assemblies (120_1 to 120_13) further accelerate the temperature change, which is an uncontrollable positive feedback. Multiple battery cell assemblies (120_1 to 120_13) in a state of thermal runaway exhibit a rapid temperature increase and emit a large amount of high-pressure gas and combustion debris.

[0075] The battery pack (100) may further include additional electrical components, such as a cooling device, a PRA (Power Relay Assembly), and a safety plug. The cooling device may include a cooling fan. The cooling fan may prevent overheating of each of the plurality of battery cell assemblies (120_1 to 120_13) 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_1 to 120_13) 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. Additional electrical components may be interposed between the plurality of battery cell assemblies (120_1 to 120_13) and the side wall (115). The space between the battery cell assemblies (120_1 to 120_13) and the side wall (115) may be referred to as an electrical component mounting area.

[0076] The battery pack (100) may further include a plurality of inter-bus bars configured to electrically connect a plurality of battery cell assemblies (120_1 to 120_13). The plurality of battery cell assemblies (120_1 to 120_13) may be connected in series by the plurality of inter-bus bars. Accordingly, the battery pack (100) may be configured to output a high voltage to an external load (e.g., a vehicle motor).

[0077]

[0078] FIG. 2 is a perspective view of a battery cell assembly (120) according to exemplary embodiments.

[0079] FIG. 3 is an exploded perspective view of a battery cell assembly (120) according to exemplary embodiments.

[0080] Each of the plurality of battery cell assemblies (120_1 to 120_13) of FIG. 1 may be substantially identical to the battery cell assembly (120) described below with reference to FIGS. 2 and 3.

[0081] The battery cell assembly (120) may include a plurality of battery cells (121), pads (122), a first integrated circuit assembly (123C), a first end plate assembly (123E), a second integrated circuit assembly (124C), a second end plate assembly (124E), a U frame (125), a top plate (126), an FFC (Flat Flexible Cable) assembly (127), TIM layers (128), and a flame cover (129).

[0082] 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 cell case (121C). The cell case (121C) may include any one of an aluminum laminate sheet, a cylindrical metal can, a square metal can, and a combination thereof. Hereinafter, the technical idea of ​​the present invention will be described with reference to an example in which the cell case (121C) is an aluminum laminate sheet. A person skilled in the art will easily arrive at an embodiment in which the cell case (121C) is any one of a cylindrical can and a square can based on the description herein.

[0083] The cell case (121C) may include an inner resin layer, a metal layer, and an outer resin layer. The inner resin layer may have thermal adhesive properties, thereby enabling sealing of the cell case (121C). The inner resin layer may include, for example, a polyolefin-based material. The metal layer may include any one of an alloy of iron, carbon, chromium, and manganese, an alloy of iron, chromium, and nickel, and aluminum.

[0084] An electrode assembly built into a cell case (121C) includes a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode. The electrode assembly may be either a jelly-roll type or a stack type. A jelly-roll type electrode assembly may include a winding structure of a positive electrode, a negative electrode, and a separator interposed therebetween. A stack type electrode assembly may include a plurality of sequentially stacked positive electrodes, a plurality of negative electrodes, and a plurality of separators interposed therebetween. The positive electrode may include a positive electrode current collector and a positive electrode active material. The negative electrode may include a negative electrode current collector and a negative electrode active material.

[0085] Each of the plurality of battery cells (121) may include a positive lead and a negative lead. The positive lead and the negative lead may be collectively referred to as electrode leads. That is, the electrode lead may refer to either the positive lead or the negative lead. The positive lead may be coupled to the negative tab of the electrode assembly. The negative lead may be coupled to the negative tab of the electrode assembly.

[0086] A plurality of battery cells (121) may be arranged in one direction. Each of the plurality of battery cells (121) may be a bidirectional cell. Accordingly, the positive and negative leads of each of the plurality of battery cells (121) may protrude in opposite directions.

[0087] Hereinafter, the technical concept of the present invention will be described based on an example in which each of the plurality of battery cells (121) is a bidirectional cell, as described above. Those skilled in the art will readily be able to arrive at an embodiment in which each of the plurality of battery cells (121) is a unidirectional cell based on the description herein.

[0088] Some of the plurality of battery cells (121) may be connected in parallel. The number of battery cells (121) connected in parallel may be determined according to the magnitude of the current to be output through the battery cell assembly (120). A group composed of battery cells (121) connected in parallel may be referred to as a bank. The plurality of battery cells (121) may form a plurality of banks, and the plurality of banks may be connected in series. The number of the plurality of banks connected in series may be determined according to the magnitude of the voltage to be output through the battery cell assembly (120).

[0089] The positive leads of the battery cells (121) of the first bank can be short-circuited with the bus bar (123P). The positive leads of the battery cells (121) of the first bank can be welded with the bus bar (123P). The negative leads of the battery cells (121) of the last bank can be short-circuited with the bus bar (123N). The negative leads of the battery cells (121) of the last bank can be welded with the bus bar (123N). The resulting voltage of the circuit composed of the plurality of battery cells (121) can be output to the outside through the bus bars (123P, 123N).

[0090] The banks between the first bank and the last bank may be referred to as intermediate banks. The negative leads of the battery cells (121) of each of the intermediate banks may be in contact with the positive leads of the battery cells (121) of the subsequent bank. The negative leads of the battery cells (121) of each of the intermediate banks may be welded to the positive leads of the battery cells (121) of the subsequent bank. The positive leads of the battery cells (121) of each of the intermediate banks may be in contact with the negative leads of the battery cells (121) of the preceding bank. The positive leads of the battery cells (121) of each of the intermediate banks may be welded to the negative leads of the battery cells (121) of the subsequent bank.

[0091] According to exemplary embodiments, the pads (122) may be polyurethane pads. According to exemplary embodiments, each of the pads (122) may include a flexible material. The pads (122) may absorb swelling of the plurality of battery cells (121). One bank or two banks may be interposed between adjacent pads (122), but are not limited thereto.

[0092] According to other exemplary embodiments, the pads (122) may be thermal barriers. According to exemplary embodiments, each of the plurality of pads (122) may have a high melting temperature and low thermal conductivity. When each of the plurality of pads (122) is a thermal barrier, each of the plurality of pads (122) may include a flame retardant material, such as ceramic and coated glass fiber.

[0093]

[0094] A first integrated circuit assembly (123IC) may be located on a first side of a battery cell assembly (120). The first integrated circuit assembly (123IC) may be coupled to a plurality of battery cells (121). The first side may have a positive lead of each of the battery cells (121) of an odd-numbered bank and a negative lead of each of the battery cells (121) of an even-numbered bank.

[0095] A first integrated circuit assembly (123IC) may include a first insulating frame and a first integrated circuit mounted on the first insulating frame. The first insulating frame may include an insulating material. The first insulating frame may support the first integrated circuit, the first bus bar (123P), the second bus bar (123N), the positive lead of each of the battery cells (121) of odd-numbered banks, and the negative lead of each of the battery cells (121) of even-numbered banks.

[0096] A first integrated circuit may be mounted on a first insulating frame. The first integrated circuit may be configured to be electrically connected to the positive leads of each of the battery cells (121) of odd-numbered banks and the negative leads of each of the battery cells (121) of even-numbered banks. The first integrated circuit may be configured to detect voltages of a plurality of nodes formed by a plurality of battery cells (121). The first integrated circuit may include a plurality of sensing plates welded to the positive leads of the battery cells (121) of odd-numbered banks and the negative leads of the battery cells (121) of even-numbered banks. The first integrated circuit may also be connected to the positive leads of each of the battery cells (121) of odd-numbered banks and the negative leads of each of the battery cells (121) of even-numbered banks via wires, in which case the plurality of sensing plates may be omitted.

[0097]

[0098] The first end plate assembly (123E) can be coupled to the U frame (125) and the top plate (126). The first end plate assembly (123E) can be welded to the U frame (125) and the top plate (126). The first end plate assembly (123E) can be on the first side of the battery cell assembly (120). The first end plate assembly (123E) can cover the first integrated circuit assembly (123IC).

[0099]

[0100] The second integrated circuit assembly (124) may be on a second side of the battery cell assembly (120). The second side may be opposite the first side. The second integrated circuit assembly (124) may be spaced apart from the first integrated circuit assembly (123IC) with a plurality of battery cells (121) therebetween. The second integrated circuit assembly (124) may be coupled to the plurality of battery cells (121). The second side may have a negative lead of each of the battery cells (121) of an odd-numbered bank and a positive lead of each of the battery cells (121) of an even-numbered bank.

[0101] The second integrated circuit assembly (124) may include a second insulating frame, a second integrated circuit, and a second insulating cover (124C). The second insulating frame may include an insulating material. The second insulating frame may support the second integrated circuit, the negative lead of each of the battery cells (121) of odd-numbered banks, and the positive lead of each of the battery cells (121) of even-numbered banks.

[0102] A second integrated circuit may be mounted on a second insulating frame. The second integrated circuit may be configured to be electrically connected to the negative leads of each of the battery cells (121) of odd-numbered banks and the positive leads of each of the battery cells (121) of even-numbered banks. The second integrated circuit may be configured to detect voltages of a plurality of nodes comprised of a plurality of battery cells (121).

[0103] The second end plate assembly (124E) can be coupled to the U frame (125) and the top plate (126). The second end plate assembly (124E) can be welded to the U frame (125) and the top plate (126). The second end plate assembly (124E) can be on the second side of the battery cell assembly (120). The second end plate assembly (124E) can cover the second integrated circuit assembly (124IC).

[0104] The U-frame (125) may have a U-shape when viewed from the front. The U-frame (125) may include a bottom plate (125B) and side walls (125W). Each of the side walls (125W) may be connected to ends of the bottom plate (125B). Each of the side walls (125W) may be substantially perpendicular to the bottom plate (125B). A top plate (126) may be coupled to the U-frame (125). The top plate (126) may be fixed to the U-frame (125) by welding. The top plate (126) and the U-frame (125) may constitute a frame assembly. Additionally, the top plate (126) and the U-frame (125) may be replaced by a mono-frame having a hollow rectangular pillar shape. The mono-frame may have substantially the same shape as the combination of the top plate (126) and the U-frame (125).

[0105]

[0106] An FFC (Flat Flexible Cable) assembly (127) may be located on a plurality of battery cells (121). The FFC assembly (127) may be interposed between the plurality of battery cells (121) and the top plate (126). The FFC assembly (127) may have an approximately linear shape. The FFC assembly (127) may connect the first integrated circuit and the second integrated circuit to each other. Voltage values ​​collected by the second integrated circuit may be transmitted to the first integrated circuit through the FFC assembly (127).

[0107] The TIM layers (128) may be interposed between the bottom plate (125B) and the battery cells (121). The TIM layers (128) may include, but are not limited to, a thermosetting material. The TIM layers (128) may be cured at room temperature. The TIM layers (128) may fix the bottom plate (125B) and the battery cells (121) to each other. The TIM layers (128) may thermally couple the bottom plate (125B) and the battery cells (121), thereby improving the cooling efficiency of the battery cell assembly (120).

[0108] The flame cover (129) may include a refractory material. The flame cover (129) may be coupled to the U-frame (125) and the top plate (126). The flame cover (129) may be fixed to the U-frame (125) and the top plate (126), for example, by an adhesive. The flame cover (129) may be coupled to the top plate (126) and the side walls (125W) of the U-frame (125). The flame cover (129) may be spaced apart from the bottom plate (125B) of the U-frame (125).

[0109]

[0110] (Example 2)

[0111] FIG. 4 is a flowchart illustrating a method for manufacturing a battery pack according to exemplary embodiments.

[0112] FIG. 5 is a perspective view illustrating a method of manufacturing a battery pack according to exemplary embodiments.

[0113] FIG. 6 is a plan view illustrating a method of manufacturing a battery pack according to exemplary embodiments.

[0114] FIG. 7 is a side view of a heat blocking pad (140_1') according to exemplary embodiments.

[0115] FIG. 8 is a cross-sectional view of a heat blocking pad (140_1') according to exemplary embodiments.

[0116] FIG. 9 is a perspective view illustrating a method of manufacturing a battery pack according to exemplary embodiments.

[0117] FIG. 10 is a plan view illustrating a method of manufacturing a battery pack according to exemplary embodiments.

[0118]

[0119] Referring to FIGS. 4 to 8, battery cell assemblies (120_1, 120_2) and heat blocking pads (140_1') can be provided. Since the battery cell assemblies (120_1, 120_2) are substantially the same as those described with reference to FIGS. 2 and 3, redundant descriptions thereof are omitted.

[0120] The heat blocking pad (140_1') may be different from the heat blocking pad (140_1) of FIG. 1. The heat blocking pad (140_1') may be coupled to the battery cell assemblies (120_1, 120_2), and thus may not be pressed by the battery cell assemblies (120_1, 120_2), and may thus have a different shape from the heat blocking pad (140_1) of FIG. 1.

[0121]

[0122] The heat blocking pad (140_1') may include a pad case (141), heat diffusion layers (143), and a heat absorbing material (145). The heat blocking pad (140_1') may be configured to be deformed by external pressure. When the pad case (141) includes multiple layers, the outermost layer may include an insulating material.

[0123] The heat diffusion layers (143) may be covered by a pad case (141). The pad case (141) may surround the heat diffusion layers (143). Each of the heat diffusion layers (143) may be interposed between the pad case (141) and a heat absorbing material (145). The heat diffusion layers (143) may be spaced apart from each other with the heat absorbing material (145) interposed therebetween. The heat absorbing material (145) may be interposed between the heat diffusion layers (143). One of the heat diffusion layers (143) may mediate heat transfer between the battery cell assembly (120_1) and the heat absorbing material (145), and the other of the heat diffusion layers (143) may mediate heat transfer between the battery cell assembly (120_2) and the heat absorbing material (145).

[0124] Each of the heat diffusion layers (143) may have high thermal conductivity. The heat diffusion layers (143) may be configured to evenly distribute heat transferred from the outside throughout the heat absorbing material (145). Each of the heat diffusion layers (143) may include a metal. Each of the heat diffusion layers (143) may include, for example, but is not limited to, copper foil.

[0125] The heat absorbing material (145) may have a high ignition point and a high specific heat. According to exemplary embodiments, the heat absorbing material (145) may include a fluid. In another example, the heat absorbing material (145) may include a powder. Accordingly, the shape of each of the plurality of cooling pouches (141) may be deformed according to pressure applied from the outside.

[0126] As a non-limiting example, the heat absorbing material (145) may include water and a superabsorbent polymer. The superabsorbent polymer is also called a SAP (Super Absorbent Polymer), a SAM (Super Absorbency Material), an AGM (Absorbent Gel Material), etc. The superabsorbent polymer absorbs water and turns into a gel, and the gel may not release the absorbed water or may release a small amount of water even under external pressure.

[0127] According to exemplary embodiments, the heat absorbing material (145) may further include a thickener. The thickener may increase the viscosity of the heat absorbing material (145). According to exemplary embodiments, the heat absorbing material (145) may further include an insulating precursor. The insulating precursor may be configured to form a porous structure (i.e., a structure in which air is trapped) in the carbonized layer during combustion. Accordingly, when the heat absorbing material (145) including the insulating precursor in addition to water and the superabsorbent resin is exposed to a thermal runaway event, the propagation of the thermal runaway may be prevented or mitigated due to the insulating action of the carbonized layer including the porous structure.

[0128] For the purpose of distinguishing the cell case (121C) and the pad case (141), the cell case (121C) may be referred to as a first pouch case, and the pad case (141) may be referred to as a second pouch case. According to exemplary embodiments, the cell case (121C) and the pad case (141) may include the same material, but are not limited thereto. The cell case (121C) and the pad case (141) may also include different materials.

[0129] The pad case (141) may cover the heat diffusion layers (143) and the heat absorption material (145). The heat diffusion layers (143) and the heat absorption material (145) may be within the pad case (141). Before being combined with the battery cell assemblies (120_1, 120_2), the pad case (141) may include a filling portion (141F), a sealing portion (141S), and an unfilled portion (141UF). The heat absorption material (145) may be within the filling portion (141F) of the pad case (141). The sealing portion of the pad case (141) may be a heat-sealed portion. The unfilled portion (141UF) of the pad case (141) may be between the filling portion (141F) and the sealing portion (141S). The unfilled portion (141UF) of the pad case (141) may be a portion that is not filled with a heat absorbing material (145). The unfilled portion (141UF) of the pad case (141) may be an unsealed portion. The unfilled portion (141UF) may be formed by a process of removing air inside the heat blocking pad (140) before sealing the heat blocking pad (140). The heat absorbing material (145) inside the filled portion (141F) of the pad case (141) may move to the unfilled portion (141UF) of the pad case (141) by external pressure.

[0130] The filling portion (141F) of the pad case (141) may be between the battery cell assemblies (120_1, 120_2) when combined with the battery cell assemblies (120_1, 120_2). The filling portion (141F) of the pad case (141) may overlap with the battery cell assemblies (120_1, 120_2) in the Y direction.

[0131] According to exemplary embodiments, the width of the filling portion (141F) may be greater than the width of the sealing portion (141S). According to exemplary embodiments, the width of the filling portion (141F) may be greater than the width of the unfilled portion (141UF). According to exemplary embodiments, the width of the unfilled portion (141UF) may be greater than the width of the sealing portion (141S).

[0132]

[0133] Next, referring to FIGS. 4, 6, 9, and 10, in P120, the battery cell assemblies (120_1, 120_2) and the heat blocking pad (140_1') can be combined. The battery cell assemblies (120_1, 120_2) and the heat blocking pad (140_1') can be fixed by an adhesive. In the process of combining the battery cell assemblies (120_1, 120_2) and the heat blocking pad (140_1'), the shape of the heat blocking pad (140_1') can be changed, so that the heat blocking pad (140_1) can be provided.

[0134] A heat shield pad (140_1) may include a middle portion (140I) and first and second ends (140E1, 140E2) of battery cell assemblies (120_1, 120_2). The middle portion (140I) may be interposed between the first and second ends (140E1, 140E2).

[0135] As the heat blocking pad (140_1') is pressed by the battery cell assemblies (120_1, 120_2), the heat absorbing material (145) may move to the first and second ends (140E1, 140E2). According to exemplary embodiments, the width of each of the first and second ends (140E1, 140E2) may be different from the width of the middle portion (140I). According to exemplary embodiments, the width of each of the first and second ends (140E1, 140E2) may be greater than the width of the middle portion (140I).

[0136] According to exemplary embodiments, the upper surface shape of the heat blocking pad (140_1) may include a dogbone shape. According to exemplary embodiments, the upper surface shape of the heat blocking pad (140_1) may include a dumbbell shape.

[0137]

[0138] Next, the assembly of battery cell assemblies (120_1, 120_2) and heat blocking pads (140_1) can be loaded onto the pack housing (100, see FIG. 1). Battery cell assemblies (120_4, 120_5) and heat blocking pads (140_2), battery cell assemblies (120_6, 120_7) and heat blocking pads (140_3), and battery cell assemblies (120_12, 120_13) and heat blocking pads (140_4) can be provided in substantially the same manner as described with reference to FIGS. 4 to 10, and thus, redundant descriptions thereof will be omitted.

[0139]

[0140] 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; First to third battery cell assemblies on the base plate, each of the first to third battery cell assemblies including a plurality of battery cells arranged in a first direction, and; a thermal insulation pad between the first and second battery cell assemblies; and A battery pack comprising a first bulkhead between the second and third battery cell assemblies.

2. In paragraph 1, A battery pack, characterized in that the length of the second direction perpendicular to the first direction of the heat blocking pad is different from the length of each of the first and second battery cell assemblies in the second direction.

3. In paragraph 1, A battery pack, characterized in that the length of the second direction perpendicular to the first direction of the heat blocking pad is greater than the length of each of the first and second battery cell assemblies in the second direction.

4. In paragraph 1, A battery pack characterized in that the heat blocking pad is spaced apart from the first bulkhead with the second battery cell assembly interposed therebetween.

5. In paragraph 1, A battery pack, characterized in that each of the first to third battery cell assemblies includes a frame assembly surrounding the plurality of battery cells and a flame cover coupled to the frame assembly.

6. In paragraph 5, A battery pack characterized in that the frame assembly comprises a U-frame and a top plate welded to each other.

7. In paragraph 5, A battery pack, wherein the heat blocking pad is in contact with the flame cover of each of the first and second battery cells.

8. In paragraph 1, A battery pack characterized in that the heat blocking pad includes a pad case, heat diffusion layers within the pad case, and a heat absorbing material.

9. In paragraph 8, A battery pack characterized in that the heat diffusion layers are spaced apart with the heat absorbing material therebetween.

10. In paragraph 8, A battery pack, wherein each of the heat diffusion layers comprises metal.

11. In paragraph 8, A battery pack characterized in that the heat absorbing material comprises water and a superabsorbent resin.

12. In paragraph 8, Each of the battery cells of the first to third battery cell assemblies includes a cell case, and A battery pack, characterized in that the cell case comprises the same material as the pad case.

13. In paragraph 1, A battery pack characterized in that the above heat blocking pad has a dog bone shape.

14. In paragraph 1, A battery pack characterized in that the above heat blocking pad has a dumbbell shape.

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