Battery pack

Abstract

According to exemplary embodiments, a battery pack is provided. The battery pack includes: a base plate; a thermal interface material (TIM) layer on the base plate; and a battery cell assembly on the TIM layer. The battery cell assembly includes: a plurality of battery cells arranged in a first direction; first and second side beams spaced apart from each other in the first direction with the plurality of battery cells therebetween; and a lifting band coupled to the first and second side beams.

Description

battery pack

[0001] The present invention relates to a battery pack. This application claims the benefit of Korean Application No. 10-2024-0019546, filed February 8, 2024, and Korean Application No. 10-2024-0151325, filed October 30, 2024, which are incorporated herein by reference in their 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] The technological development trend in secondary batteries for mobility is improving energy density and safety. The energy density of a secondary battery is defined as the maximum electrical energy it can store divided by its mass. High energy density in secondary batteries is directly linked to driving efficiency and range in mobility, and therefore, various studies are being conducted to improve the energy density of secondary batteries.

[0004] The technical idea of ​​the present invention aims to solve a problem by providing a battery pack that is easy to service after-sales.

[0005] According to exemplary embodiments for solving the above-described problem, a battery pack is provided. The battery pack includes: a base plate; a TIM (Thermal Interface Material) layer on the base plate; and a battery cell assembly on the TIM layer, wherein the battery cell assembly includes a plurality of battery cells arranged in a first direction, first and second side beams spaced apart from each other in the first direction with the plurality of battery cells interposed therebetween, and a lifting band coupled to the first and second side beams.

[0006] The lifting band includes a first portion interposed between the base plate and the plurality of battery cells.

[0007] The first part of the lifting band is at the same level as the TIM layer based on the mounting surface of the base plate.

[0008] The lifting band includes a second portion connected to the first portion and covering the first side beam, and a third portion connected to the first portion and covering the second side beam.

[0009] The lifting band includes a fourth portion connected to the second portion and including a bolting hole, and a fifth portion connected to the third portion and including a bolting hole.

[0010] The battery pack further includes a cross beam on the base plate, wherein the cross beam extends in a second direction perpendicular to the first direction.

[0011] The above cross beam includes a groove into which the fourth portion of the above lifting band is inserted.

[0012] The above battery cell assembly includes a fixture that secures the lifting band and the first side beam to each other.

[0013] The battery pack further includes a first friction reducing sheet between the cross beam and the first side beam.

[0014] The battery pack further includes a second friction reducing sheet between the cross beam and the first side beam.

[0015] The first friction reducing sheet is bonded to the first side beam, and the second friction reducing sheet is bonded to the cross beam.

[0016] The above battery pack further includes a tape between the TIM layer and the base plate.

[0017] The above tape contains aluminum.

[0018] The above tape comprises the same material as the above base plate.

[0019] According to exemplary embodiments, a battery pack is provided. The battery pack comprises: a base plate; a cross beam on the base plate; a TIM layer on the base plate; a battery cell assembly on the TIM layer, the battery cell assembly including a plurality of battery cells, first and second side beams spaced apart from each other in a first direction with the plurality of battery cells interposed therebetween, and a lifting band coupled to the first and second side beams; and a first friction reducing sheet between the cross beam and the first side beam.

[0020] The first friction relief sheet is bonded to one of the cross beam and the first side beam.

[0021] It further includes a second friction relief sheet between the cross beam and the first side beam.

[0022] The first friction reducing sheet is bonded to the first side beam, and the second friction reducing sheet is bonded to the cross beam.

[0023] According to exemplary embodiments of the present invention, a battery pack includes a battery cell assembly comprising a tape and a lifting band interposed between a thermal interface material (TIM) layer and a base plate. Accordingly, when a quality issue occurs in some of the battery cell assemblies, they can be separated and replaced.

[0024] 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.

[0025] FIG. 1 is a perspective view of a battery pack according to exemplary embodiments.

[0026] FIG. 2 is an exploded perspective view of a battery pack according to exemplary embodiments.

[0027] FIG. 3 is a partial perspective view of a battery pack according to exemplary embodiments.

[0028] FIG. 4 is a perspective view illustrating a lifting band of a battery cell assembly according to exemplary embodiments.

[0029] Figure 5 is a cross-sectional view taken along the cutting line 1I-1I' of Figure 1.

[0030] Figure 6 is a cross-sectional view taken along the cutting line 1II-1II' of Figure 1.

[0031] FIG. 7 is a cross-sectional view illustrating a battery pack according to other exemplary embodiments.

[0032] FIG. 8 is a cross-sectional view illustrating a battery pack according to other exemplary embodiments.

[0033] FIG. 9 is a flowchart illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0034] FIGS. 10 to 16 are cross-sectional views illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039]

[0040] (Example 1)

[0041] FIG. 1 is a perspective view of a battery pack (100) according to exemplary embodiments.

[0042] FIG. 2 is an exploded perspective view of a battery pack (100) according to exemplary embodiments.

[0043] FIG. 3 is a partial perspective view of a battery pack (100) according to exemplary embodiments.

[0044] FIG. 4 is a perspective view showing a lifting band (127) of a battery cell assembly (120) according to exemplary embodiments.

[0045] Figure 5 is a cross-sectional view taken along the cutting line 1I-1I' of Figure 1.

[0046] Figure 6 is a cross-sectional view taken along the cutting line 1II-1II' of Figure 1.

[0047]

[0048] Referring to FIGS. 1 to 6, a battery pack (100) may include a pack housing (110), a plurality of battery cell assemblies (120), tapes (130), TIM (Thermal Interface Material) layers (140), and friction-reducing sheets (151). The battery pack (100) is the final form of a battery system mounted on mobility, etc.

[0049] The pack housing (110) may include a base plate (111) and side walls (112, 113, 114, 115). Here, two directions substantially parallel to the mounting surface (111M) of the base plate (111) are defined as the X direction and the Y direction, and a direction substantially perpendicular to the mounting surface (111M) of the base plate (111) is defined as the Z direction. The X direction, the Y direction, and the Z direction may be substantially perpendicular to each other.

[0050] The base plate (111) may have a flat shape. The side walls (112, 113, 114, 115) may be substantially perpendicular to the base plate (111). The side walls (112, 113, 114, 115) may be adjacent to edge portions of the base plate (111). The side walls (112, 113, 114, 115) may be joined to edge portions of the base plate (111).

[0051] The base plate (111) may include a plurality of plates joined by friction stir welding. Each of the plurality of plates and side walls (112, 113) of the base plate (111) may be provided by an extrusion process. The side walls (114, 115) may also be provided by an extrusion process.

[0052] The base plate (111) may further include a center beam (116) and cross beams (117, 118). According to exemplary embodiments, the center beam (116) may extend in the X direction. The center beam (116) may be included in one of the plurality of plates of the base plate (111) and formed by an extrusion process together with one of the plurality of plates, or may be welded to one of the plurality of plates of the base plate (111).

[0053] The center beam (116) and cross beams (117, 118) can define a space in which the battery cell assembly (120) is mounted. The center beam (116) can be surrounded by side walls (112, 113, 114, 115). Accordingly, the center beam (116) can divide the space defined by the pack housing (110).

[0054] The center beam (116) can isolate the battery cell assemblies (120) in the Y direction. The center beam (116) can be interposed between the battery cell assemblies (120) in the Y direction. The cross beams (117, 118) can isolate the plurality of battery cell assemblies (120) in the X direction. The cross beam (117) can be interposed between the battery cell assemblies (120) in the X direction. The cross beam (118) can be interposed between the battery cell assemblies (120) and the side wall (115).

[0055] A plurality of battery cell assemblies (120) may be arranged on a mounting surface (111M) of a base plate (111) of a pack housing (110). The battery cell assemblies (120) may be arranged in the X direction and the Y direction. In this example, three battery cell assemblies (120) are arranged in the X direction, and two battery cell assemblies are arranged in the Y direction, so that the plurality of battery cell assemblies (120) form a matrix of two rows and three columns. However, this is for illustrative purposes and does not limit the technical idea of ​​the present invention in any sense.

[0056] The base plate (111) can support a plurality of battery cell assemblies (120). The side walls (112, 113, 114, 115) can horizontally surround the plurality of battery cell assemblies (120).

[0057] Hereinafter, the technical concept of the present invention will be described with reference to an embodiment in which the battery pack (100) is a modular type and each of the plurality of battery cell assemblies (120) does not include a module frame. However, this is a non-limiting example and does not limit the technical concept of the present invention in any sense. A person skilled in the art will easily be able to achieve a plurality of battery cell assemblies including a module frame and a module-type battery pack including the same based on the description herein.

[0058] Each of the plurality of battery cell assemblies (120) may include a plurality of battery cells (121) and an integrated circuit assembly (123), side beams (125), a lifting band (127), and fixtures (128, 129).

[0059] Each of the plurality of battery cells (121) may include 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 square battery cell, and a pouch-type battery cell. The electrode assembly of the cylindrical battery cell is housed in a cylindrical metal can. The electrode assembly of the square battery cell is housed in a square metal can. The electrode assembly of the pouch-type battery cell is housed in a pouch case including an aluminum laminate sheet.

[0060] The electrode assembly includes an anode, a cathode, and a separator interposed between the anode and the cathode. A jelly roll type electrode assembly is formed by winding an anode, a cathode, and a separator interposed between them. A stack type electrode assembly includes a plurality of sequentially stacked anodes, a plurality of cathodes, and a plurality of separators interposed between them.

[0061] According to exemplary embodiments, a plurality of battery cells (121) may constitute a plurality of banks. The plurality of banks may include one or more parallel-connected battery cells (121). The plurality of banks may be connected in series with each other. The number of battery cells (121) included in each of the plurality of banks and the number of banks connected in series with each other may be determined according to the voltage and current to be output through each of the plurality of battery cell assemblies (120).

[0062] According to exemplary embodiments, the cell stack may further include a plurality of separators. The plurality of separators may be interposed between the plurality of battery cells (121). The plurality of separators may include a flexible material and may absorb swelling of the plurality of battery cells. According to exemplary embodiments, the plurality of separators may be thermal barriers. According to exemplary embodiments, each of the plurality of separators may have a high melting temperature and low thermal conductivity. According to exemplary embodiments, each of the plurality of separators may include a flame retardant material, such as a ceramic or coated glass material. According to exemplary embodiments, the plurality of separators may be configured to release a fire retardant material and a fire extinguishing agent when a thermal runaway event occurs.

[0063] The integrated circuit assembly (123) may include an insulating frame, an integrated circuit, bus bars, sensing plates, sensing bars, temperature sensors, wires, and an insulating cover. The integrated circuit assembly (123) may include physical and functional components for providing electrical connections between a plurality of battery cells (121), outputting a resulting voltage of the plurality of battery cells (121), and measuring voltages (or currents) of nodes within a circuit composed of the plurality of battery cells (121).

[0064] 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, sensing plates, sensing bars, temperature sensors, and wiring.

[0065] The bus bars may be short-circuited to the positive leads of the battery cells (121) of the first bank and 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 the battery cells (121) of the first bank and the negative leads of one or more battery cells (121) of the last bank. The resulting voltage of the plurality of battery cells (121) of the battery cell assembly (120) may be output through the bus bars. The bus bars may be fixed to the insulating frame.

[0066] The integrated circuit may be mounted on an insulating frame. The positive and negative leads, which are welded together, may form nodes within the battery cell assembly (120). The integrated circuit may be configured to measure the voltages of the nodes via sensing plates and sensing bars.

[0067] The sensing bars may include a conductive material. The sensing bars may have a rod-like shape. The sensing bars may be short-circuited to the bus bars. The sensing bars may be coupled to the bus bars. The voltage of the bus bars may be measured through the sensing bars.

[0068] Each of the plurality of sensing plates may have a patch shape or a pad shape. The plurality of sensing plates may include a conductive material. The plurality of sensing plates may be short-circuited to corresponding positive and negative leads of the plurality of battery cells (121).

[0069] Each of the plurality of sensing plates can be connected to an integrated circuit. Through the plurality of sensing plates, the voltages of the plurality of nodes within the battery cell assembly (120) can be measured.

[0070] The temperature sensors may be configured to measure the temperature of multiple points of the battery cell assembly (120). The temperature sensors may be spatially arranged, thereby allowing the temperature distribution within the battery cell assembly (120) to be measured.

[0071] The insulating cover may include an insulating material, such as plastic. The insulating cover may be fitted to the insulating frame. The insulating cover may cover the integrated circuit, bus bars, sensing plates, sensing bars, and temperature sensors, thereby protecting the electrical components of the first and second integrated circuit assemblies.

[0072] The side beams (125) may be spaced apart from each other with a plurality of battery cells (121) therebetween. The side beams (125) may have substantially the same shape as each other. The side beams (125) may include aluminum. The side beams (125) may be provided by an extrusion process. The side beams (125) may be arranged symmetrically with respect to the plurality of battery cells (121). Each of the side beams (125) may include a plate portion (125P) and a joining portion (125C). Each of the side beams (125) may have an approximate shape of the Greek letter 'Γ'.

[0073] Each plate portion (125P) of each of the side beams (125) may have a flat plate shape perpendicular to the X direction. Each of the coupling portions (125C) of the side beams (125) may include a plurality of bolting holes. Fixtures (128) and fixtures (129) may be coupled to the coupling portions (125C) of each of the side beams (125). The fixtures (128) may fix the side beams (125) and the cross beams (117, 118) to each other. The fixtures (129) may fix the side beams (125) and the lifting bands (127) to each other.

[0074] Each of the side beams (125) may include a groove (125G). A lifting band (127) may be inserted into the groove (125G). The lifting band (127) may include a metallic material. The lifting band (127) may include first to seventh portions (127P1, 127P2, 127P3, 127P4, 127P5, 127P6, 127P7).

[0075] The first portion (127P1) may extend in the X direction. The first portion (127P1) may overlap the plurality of battery cells (121) in the Z direction. The first portion (127P1) may be in contact with the plurality of battery cells (121). The first portion (127P1) may support the plurality of battery cells (121), and thus, when the plurality of battery cell assemblies (120) are placed on the pack housing (110) or lifted from the pack housing (110), sagging of the plurality of battery cells (121) may be prevented or alleviated.

[0076] The second part (127P2) and the third part (127P3) can be connected to the first part (127P1). The second part (127P2) and the third part (127P3) can be spaced apart from each other with the first part (127P1) therebetween. The second part (127P2) and the third part (127P3) can extend in the Z direction. The lifting band (127P) can include a curved portion between the second part (127P2) and the first part (127P1) and a curved portion between the third part (127P3) and the first part (127P1). The second part (127P2) of the lifting band (127P) can cover the cross beam (125). The third part (127P3) of the lifting band (127P) can cover the cross beam (125).

[0077] The fourth part (127P4) may be connected to the second part (127P2). The fourth part (127P4) may be spaced apart from the first part (127P1) with the second part (127P2) therebetween. The fourth part (127P4) may extend in the X direction. The lifting band (127P) may include a bent portion between the fourth part (127P4) and the second part (127P2). The fourth part (127P4) may include bolting holes (127H) for coupling with the fixing members (129). The fourth part (127P4) may be inserted into a groove (125G) of the side beam (125).

[0078] The fifth portion (127P5) may be connected to the third portion (127P3). The fifth portion (127P5) may be spaced apart from the first portion (127P1) with the third portion (127P3) therebetween. The fifth portion (127P5) may extend in the X direction. The lifting band (127P) may include a bent portion between the fifth portion (127P5) and the third portion (127P3). The fifth portion (127P5) may include bolting holes (127H) for coupling with the fixing members (129). The fifth portion (127P5) may be inserted into a groove (125G) of the side beam (125).

[0079] The sixth portion (127P6) may be connected to the fourth portion (127P4). The sixth portion (127P6) may be spaced apart from the second portion (127P2) with the fourth portion (127P4) therebetween. The sixth portion (127P6) may extend in the Z direction. The lifting band (127P) may include a curved portion between the sixth portion (127P6) and the fourth portion (127P4).

[0080] The seventh portion (127P7) may be connected to the fifth portion (127P5). The seventh portion (127P7) may be spaced apart from the third portion (127P3) with the fifth portion (127P5) therebetween. The seventh portion (127P7) may extend in the Z direction. The lifting band (127P) may include a curved portion between the seventh portion (127P7) and the fifth portion (127P5).

[0081] TIM layers (140) may be provided on the base plate (111) of the pack housing (110). The TIM layers (140) may be interposed between each of the plurality of battery cell assemblies (120) and the base plate (111). The TIM layers (140) may include a resin composition. The TIM layers (140) may be provided by a thermal resin application process.

[0082] In the example of FIG. 2, there are no TIM layers (140) at the center of the Y direction of each of the plurality of battery cell assemblies (120), and two TIM layers (140) are shown corresponding to each of the plurality of battery cell assemblies (120) (i.e., overlapping in the Z direction), but this is for illustration only and does not limit the technical idea of ​​the present invention in any sense.

[0083] A first portion (127P1) of the lifting band (127) of each of the plurality of battery cell assemblies (120) may be interposed between the TIM layers (140) in the Y direction. The first portion (127P1) of the lifting band (127) of each of the plurality of battery cell assemblies (120) may be at the same level with respect to the TIM layers (140) and the mounting surface (111M) of the base plate (111).

[0084] 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.

[0085] The curing agent of the resin composition may be selected depending on the subject matter of the resin composition. For example, if the subject matter of the resin composition is a silicone resin, the curing agent may be a siloxane compound. If the subject matter of the resin composition is a polyol resin, the curing agent may use an isocyanate compound. If the subject matter of the resin composition is an epoxy resin, the curing agent may use an amine compound. If the subject matter of the resin composition is an acrylic resin, the curing agent may be an isocyanate compound.

[0086] The inorganic filler of the resin composition may have relatively high thermal conductivity. According to exemplary embodiments, the thermal conductivity of the inorganic filler of the resin composition may be about 1 W / mK or more. According to exemplary embodiments, the thermal conductivity of the inorganic filler of the resin composition may be about 5 W / mK or more. According to exemplary embodiments, the thermal conductivity of the inorganic filler of the resin composition may be about 10 W / mK or more. According to exemplary embodiments, the thermal conductivity of the inorganic filler of the resin composition may be about 15 W / mK or more.

[0087] According to exemplary embodiments, the inorganic filler of the resin composition may include a ceramic. For example, the inorganic filler of the resin composition may include any one of aluminum oxide (Al2O3), aluminum nitride (AlN), boron nitride (BN), silicon nitride (Si3N4), silicon carbide (SiC), beryllium oxide (BeO), zinc oxide (ZnO), aluminum hydroxide (Al(OH)3), and boehmite. The resin composition may also include a carbon filler. For example, the resin composition may include any one of fumed silica, clay, and calcium carbonate.

[0088] Each of the tapes (130) may be on a base plate. The tapes (130) may be interposed between the TIM layers (140) and the base plate (111). According to exemplary embodiments, each of the tapes (130) may include the same material as the base plate (111). Each of the tapes (130) may be, for example, an aluminum tape. The tapes (130) may contact each of the TIM layers (140) and the base plate (111). The tapes (130) may cover the base plate (111), and thus, each of the TIM layers (140) may not contact the base plate (111). Each of the TIM layers (140) may be spaced apart from the base plate (111).

[0089] According to exemplary embodiments, the tapes (130) may include aluminum. The tapes (130) including aluminum may have high thermal conductivity, thereby preventing a decrease in the cooling performance of the battery pack (100). In addition, the tapes (130) including aluminum may have an appropriate range of adhesive strength with the TIM layers (140).

[0090] Friction reducing sheets (151) may be interposed between the side beams (125) and the cross beams (117) and between the side beams (125) and the cross beams (118). The friction reducing sheets (151) may be bonded to the side beams (125) or to the cross beams (117, 118).

[0091] Each of the friction reducing sheets (151) may include, but is not limited to, Teflon. The friction reducing sheets (151) may reduce the frictional force between the side beams (125) and the cross beams (117, 118) when placing the plurality of battery cells (125) on the pack housing (110) and when lifting the plurality of battery cells (125) from the pack housing (110).

[0092] According to exemplary embodiments, the tapes (130) isolate the base plate (111) and the TIM layers (140), so that the base plate (111) and the TIM layers (140) do not come into direct contact, and thus, when removing any one of the battery cell assemblies (120), the corresponding TIM layers (140) can be efficiently removed. According to exemplary embodiments, since the tapes (130) are interposed between the TIM layers (140) and the base plate (111), separation of the battery cell assemblies (120) and the base plate (111) is possible even after curing of the TIM layers (140).

[0093] At this time, due to the use of the battery pack (100), swelling may occur in the plurality of battery cells (121), and the vertical force between the side beam (125) and the cross beams (117, 118) may increase. According to exemplary embodiments, friction reducing sheets (151) are interposed between the side beam (125) and the cross beam (117) and between the side beam (125) and the cross beam (118), so that even when swelling occurs in the plurality of battery cells (121), the battery cell assemblies (120) can be easily lifted from the pack housing (110).

[0094] The battery pack (100) may include exhaust devices. The exhaust devices may be coupled to any one of the side walls (112, 113, 114, 115). The side walls (112, 113, 114, 115) coupled to the exhaust devices may include exhaust paths 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 at least one of the plurality of battery cell assemblies (120) is in a thermal runway state.

[0095] 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.

[0096] The battery pack (100) may include leads coupled to side walls (112, 113, 114, 115). The leads may cover elements disposed within the battery pack (100), such as battery cell assemblies (120) and electrical components. The leads may be secured to the battery pack (100) by mechanical fastening means, such as bolts.

[0097] The battery pack (100) may further include inter-busbars. A plurality of battery cell assemblies (120) may be connected in series by the inter-busbars, and the battery pack (100) may output a high voltage.

[0098] The battery pack (100) may further include electrical components. The electrical components may be positioned on the pack housing (110). The electrical components may be positioned between any one of the side walls (112, 113, 114, 115) on which the exhaust devices are installed and the plurality of battery cell assemblies (120).

[0099] The electrical components may include, for example, a 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 sensors for measuring the voltage, current, and temperature described above.

[0100] 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).

[0101] 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.

[0102]

[0103] (Example 2)

[0104] FIGS. 7 and 8 are cross-sectional views illustrating a battery pack (100') according to other exemplary embodiments. Referring to FIGS. 1 to 6, the battery pack (100') may include a pack housing (110), a plurality of battery cell assemblies (120), tapes (130), TIM layers (140), and friction-reducing sheets (151, 153). The battery pack (100') is the final form of a battery system mounted on a mobility device, etc.

[0105] The pack housing (110), the plurality of battery cell assemblies (120), the tapes (130), the TIM layers (140), and the friction relief sheets (151) are substantially the same as those described with reference to FIGS. 1 to 6, so a duplicate description thereof is omitted.

[0106] Referring to FIGS. 7 and 8, friction reducing sheets (153) may be interposed between the side beams (125) and the cross beams (117) and between the side beams (125) and the cross beams (118). The friction reducing sheets (151) may be adhered to the side beams (125), and the friction reducing sheets (153) may be adhered to the cross beams (117, 118). Each of the friction reducing sheets (153) may include, but is not limited to, Teflon. According to exemplary embodiments, by providing additional friction reducing sheets (153) between the side beams (125) and the cross beams (117, 118), the battery cell assemblies (120) may be more easily lifted from the pack housing (110) even when swelling occurs in the plurality of battery cells (121).

[0107]

[0108] (Example 3)

[0109] FIG. 9 is a flowchart illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0110] Figures 10 to 16 are cross-sectional views illustrating a method for manufacturing a secondary battery according to exemplary embodiments. Figures 9 to 15 are cross-sectional views showing portions corresponding to Figure 6.

[0111] Referring to FIGS. 5, 9, and 10, at P110, the battery cell assembly (120) can be removed. Since the adhesive force between the tape (130) and the TIM layers (140) is weaker than the adhesive force between the base plate (111) and the TIM layers (140), the battery cell assembly (120) can be easily separated from the tape (130). In addition, even when a plurality of battery cells (121) of the battery cell assembly (120) are swollen, the frictional force in the vertical direction (i.e., the Z direction) is reduced due to the friction reducing sheet (151), so that the battery cell assembly (120) can be easily removed.

[0112] Next, referring to FIGS. 9, 10, and 11, at P120, the friction reducing sheets (151) can be removed. In this example, the friction reducing sheets (151) attached to the cross beams (117, 118) are removed. In the example where the friction reducing sheets (151) are attached to the battery cell assembly (120, see FIG. 5), the friction reducing sheets (151) are removed together with the battery cell assembly (120), and thus P120 can be omitted. Unlike in FIG. 11, the TIM layers (140) may partially remain on the tape (130).

[0113] Next, referring to FIGS. 9, 11, and 12, at P130, the tape (130) can be removed. The tape (130) can be separated by mechanical or chemical methods. At P130, portions of the remaining TIM layers (140, see FIG. 10) can be removed together with the tape (130).

[0114] Next, referring to FIGS. 9, 12 and 13, at P140, a tape (130') can be provided. The tape (130') can be attached to the base plate (111).

[0115] Next, referring to FIGS. 9, 13, and 14, at P150, a friction reducing sheet (151') may be provided. In this example, the friction reducing sheet (151') is attached to the cross beams (117, 118). In an example where the friction reducing sheet (151') is attached to the battery cell assembly (120, see FIG. 5), P150 may be omitted.

[0116] Next, referring to FIGS. 9, 14, and 15, at P160, TIM layers (140') can be provided. The TIM layers (140') can be provided by a thermal resin application process. The TIM layers (140') can be applied on the tape (130').

[0117] Next, referring to FIGS. 9, 14 and 16, at P170, the battery cell assembly (120) can be mounted on the base plate (111). The battery cell assembly (120) can be fixed to the tape (130') by TIM layers (140').

[0118]

[0119] 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. Base plate; A TIM (Thermal Interface Material) layer on the base plate; and Including a battery cell assembly on the above TIM layer, A battery pack comprising a plurality of battery cells arranged in a first direction, first and second side beams spaced apart from each other in the first direction with the plurality of battery cells interposed therebetween, and a lifting band coupled to the first and second side beams.

2. In paragraph 1, A battery pack, characterized in that the lifting band includes a first portion interposed between the base plate and the plurality of battery cells.

3. In paragraph 2, A battery pack characterized in that the first part of the lifting band is at the same level as the TIM layer based on the mounting surface of the base plate.

4. In paragraph 3, A battery pack, characterized in that the lifting band includes a second part connected to the first part and covering the first side beam, and a third part connected to the first part and covering the second side beam.

5. In paragraph 4, A battery pack characterized in that the lifting band includes a fourth portion connected to the second portion and including a bolting hole, and a fifth portion connected to the third portion and including a bolting hole.

6. In paragraph 5, Further comprising a cross beam on the base plate, A battery pack, characterized in that the cross beam extends in a second direction perpendicular to the first direction.

7. In paragraph 6, A battery pack, characterized in that the cross beam includes a groove into which the fourth portion of the lifting band is inserted.

8. In paragraph 6, A battery pack, characterized in that the battery cell assembly includes a fixing member that fixes the lifting band and the first side beam to each other.

9. In paragraph 6, A battery pack further comprising a first friction relief sheet between the cross beam and the first side beam.

10. In paragraph 9, A battery pack, characterized in that the first friction relief sheet is bonded to one of the cross beam and the first side beam.

11. In paragraph 9, A battery pack further comprising a second friction reducing sheet between the cross beam and the first side beam.

12. In paragraph 11, The first friction relief sheet is bonded to the first side beam, and A battery pack, characterized in that the second friction relief sheet is adhered to the cross beam.

13. In paragraph 1, A battery pack further comprising a tape between the base plate and the TIM layer.

14. In paragraph 13, A battery pack characterized in that the tape comprises aluminum.

15. In paragraph 13, A battery pack, characterized in that the tape comprises the same material as the base plate.

16. Base plate; Cross beam on the above base plate; TIM layer on the above base plate; A battery cell assembly on the TIM layer, wherein the battery cell assembly comprises a plurality of battery cells, first and second side beams spaced apart from each other in a first direction with the plurality of battery cells interposed therebetween, and a lifting band coupled to the first and second side beams; and A battery pack comprising a first friction relief sheet between the cross beam and the first side beam.

17. In paragraph 16, A battery pack, characterized in that the first friction relief sheet is bonded to one of the cross beam and the first side beam.

18. In paragraph 16, A battery pack further comprising a second friction reducing sheet between the cross beam and the first side beam.

19. In paragraph 18, The first friction relief sheet is bonded to the first side beam, and A battery pack, characterized in that the second friction relief sheet is adhered to the cross beam.

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