Method of manufacturing a secondary battery

Abstract

Embodiments provide a method of manufacturing a secondary battery. The method includes preparing a battery pack case and a gasket, wherein the battery pack case includes a bottom plate and a side wall perpendicular to the bottom plate, and the gasket includes an un-magnetized portion and a sealing portion coupled to the un-magnetized portion; and assembling the gasket assembly to the battery pack case using a magnetic force.

Description

Technical Field

[0001] This disclosure relates to a method for manufacturing a secondary battery. This application claims the benefit of priority based on Korean Patent Application No. 10-2024-0100454, filed on July 29, 2024, the entire contents of which are incorporated herein by reference. Background Technology

[0002] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. They are widely used as a power source for various types of wireless devices, such as handheld devices, laptops, and cordless vacuum cleaners. Recently, the primary use of secondary batteries has shifted from mobile devices to mobility, as the manufacturing cost per unit capacity has decreased significantly due to improvements in energy density and economies of scale, and the driving range of battery electric vehicles (BEVs) has increased to the same level as that of fuel cell vehicles.

[0003] Battery cell manufacturers are paying huge capital expenditures to meet surging battery demand. In addition to meeting high consumer demand, increasing the capacity of methods for manufacturing rechargeable batteries can also help reduce the capital expenditure required per unit of capacity (e.g., GWh), and is therefore very important throughout the rechargeable battery industry. Summary of the Invention

[0004] Technical issues

[0005] This disclosure aims to provide a method for manufacturing secondary batteries that improves productivity.

[0006] Technical solution

[0007] Embodiments of this disclosure provide a method for manufacturing a secondary battery. The method includes: preparing a battery pack housing and a gasket, wherein the battery pack housing includes a base plate and a sidewall perpendicular to the base plate, and the gasket includes an unmagnetized portion and a sealing portion coupled to the unmagnetized portion; and assembling the gasket assembly to the battery pack housing using magnetic force.

[0008] The unmagnetized portion may contain one of the following: iron, nickel, cobalt, steel, ferroalloys, soft iron, silicon steel, ferrite, μ metal, nickel-iron alloys, amorphous metals, and ultrapure aluminum.

[0009] The sealing component may contain one of the following: silicone rubber, ethylene propylene diene monomer (EPDM) rubber, nitrile rubber, fluorosilicone rubber, fluororubber, natural rubber, polytetrafluoroethylene, polyurethane, chloroprene rubber, and polycarbonate.

[0010] The unmagnetized portion can be embedded in the sealed portion.

[0011] The unmagnetized portion of the tongue can be inserted into the sealing portion.

[0012] The sealed part and the unmagnetized part can be joined together by an interference fit.

[0013] The method may also include removing residual magnetism from the gasket.

[0014] Residual magnetism in the gasket can be removed by coercivity.

[0015] Residual magnetism in the gasket can be removed using an alternating magnetic field.

[0016] Residual magnetism in the gasket can be removed using a high-frequency pulsed magnetic field.

[0017] An embodiment provides a battery pack. The battery pack includes: a battery pack housing, the battery pack housing including a base plate and a side wall perpendicular to the base plate; a plurality of battery cell assemblies located on the base plate; and a gasket located on the side wall, the gasket including an unmagnetized portion and a sealing portion coupled to the unmagnetized portion.

[0018] The unmagnetized portion may contain one of the following: iron, nickel, cobalt, steel, ferroalloys, soft iron, silicon steel, ferrite, μ metal, nickel-iron alloys, amorphous metals, and ultrapure aluminum.

[0019] The sealing component may contain one of the following: silicone rubber, ethylene propylene diene monomer (EPDM) rubber, nitrile rubber, fluorosilicone rubber, fluororubber, natural rubber, polytetrafluoroethylene, polyurethane, chloroprene rubber, and polycarbonate.

[0020] Beneficial effects

[0021] According to embodiments of this disclosure, the gasket can be magnetically assembled to the battery pack housing using an assembly robot. Therefore, the assembly process of the battery pack housing can be automated, and the production capacity of secondary battery manufacturing can be increased.

[0022] The effects achievable from the embodiments of this disclosure are not limited to those described above, and other effects not described herein will be clearly derived and understood by those skilled in the art from the following description. In other words, unintended effects achieved when implementing the embodiments of this disclosure can be derived by those skilled in the art from the embodiments of this disclosure. Attached Figure Description

[0023] Figure 1 This is a flowchart of a method for manufacturing a secondary battery according to an embodiment.

[0024] Figure 2 This is a diagram illustrating a method for manufacturing a secondary battery according to an embodiment.

[0025] Figure 3A gasket according to an embodiment is shown.

[0026] Figure 4 yes Figure 3 A cross-sectional view of the gasket.

[0027] Figure 5 A gasket according to another embodiment is shown.

[0028] Figure 6 yes Figure 5 A cross-sectional view of the gasket.

[0029] Figure 7 This is a plan view used to describe the battery pack according to an embodiment. Detailed Implementation

[0030] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Before describing the embodiments of the present disclosure, the terms or expressions used in this specification and claims should not be construed as limited to their common understanding or as defined in common dictionaries, and should be understood based on the principle that the inventors of this application can appropriately define the terms or expressions to best interpret the present disclosure, according to the meanings and concepts corresponding to the present disclosure.

[0031] Therefore, the embodiments described herein and the configurations shown in the accompanying drawings are merely examples of this disclosure and do not reflect all the technical concepts of this disclosure. It should be understood that various equivalents and modifications have been made to replace these configurations as of the date of filing of this application.

[0032] When it is determined that a known configuration or function related to this disclosure would obscure the subject matter of this disclosure due to unnecessary detail, the known configuration or function is not described in detail.

[0033] Because the embodiments of this disclosure are provided to explain the disclosure more fully to those skilled in the art, the shapes, dimensions, etc. of the components shown in the drawings may be enlarged, omitted, or schematically illustrated for clarity. Therefore, it should not be construed that the dimensions or proportions of the components completely reflect their actual dimensions or proportions.

[0034] (First embodiment)

[0035] Figure 1 This is a flowchart of a method for manufacturing a secondary battery according to an embodiment.

[0036] Figure 2 This is a diagram illustrating a method for manufacturing a secondary battery according to an embodiment.

[0037] Figure 3 A gasket according to an embodiment is shown.

[0038] Figure 4 yes Figure 3A cross-sectional view of the gasket.

[0039] Reference Figures 1 to 4 In P110, a battery pack housing 110 and a gasket 130 can be prepared.

[0040] The battery pack housing 110 may include a base plate 111, side walls 112, 113, 114, and 115, and a central beam 117. The base plate 111 and each of the side walls 112 and 113 can be formed by an extrusion process. The extrusion direction of the base plate 111 and each of the side walls 112 and 113 may be the X-axis direction. The side walls 114 and 115 can be formed by an extrusion process. The side walls 112, 113, 114, and 115 may be substantially perpendicular to the base plate 111.

[0041] Side walls 112, 113, 114, and 115 may be located on the edge of the base plate 111. Side walls 112 and 113 may be attached to the edge portion of the base plate 111 parallel to the X-axis. Side walls 114 and 115 may be attached to the edge portion of the base plate 111 parallel to the Y-axis.

[0042] Each of sidewalls 112 and 113 may be substantially perpendicular to the Y-axis direction. Sidewalls 112 and 113 may each extend along the X-axis direction. Each of sidewalls 114 and 115 may be substantially perpendicular to the X-axis direction. Each of sidewalls 114 and 115 may extend along the Y-axis direction.

[0043] According to an embodiment, the base plate 111 and the side walls 112 and 113 can be joined by friction stir welding. The base plate 111 may include multiple unit plates joined to each other by friction stir welding. The side walls 114 and 115 can be joined to the base plate 111 by spot welding.

[0044] The base plate 111 may include multiple cooling channels. These cooling channels can provide pathways for the movement of, for example, a refrigerant (such as water). The multiple cooling channels can be formed by an extrusion process. The multiple cooling channels may extend along the X-axis. The multiple cooling channels may be spaced apart from each other in the Y-axis direction.

[0045] Gasket 130 can be disposed on the upper surfaces 112U, 113U, 114U, and 115U of sidewalls 112, 113, 114, and 115U. Double-ended bolts 116 can be located on the upper surfaces 112U and 113U of sidewalls 112 and 113. Double-ended bolts 116 can be used not only to secure the battery pack housing 110 and the cover, but also to guide the alignment of gasket 130 with the battery pack housing 110.

[0046] According to an embodiment, the gasket 130 may include an unmagnetized portion 131 and a sealing portion 133. The unmagnetized portion 131 may contain a material different from that of the sealing portion 133. According to an embodiment, the gasket 130 may be formed by insert molding the unmagnetized portion 131. Thus, the unmagnetized portion 131 may be embedded in the sealing portion 133. Except for mechanical tools, the unmagnetized portion 131 may be covered by the sealing portion 133 and therefore may not be exposed to the outside.

[0047] According to an embodiment, the unmagnetized portion 131 may contain a material capable of self-alignment in response to an external magnetic field. According to an embodiment, the unmagnetized portion 131 may contain one of iron, nickel, cobalt, steel, ferroalloys, soft iron, silicon steel, ferrite, mu-metal, nickel-iron alloys, amorphous metals, and ultrapure aluminum.

[0048] The sealing portion 133 may surround the unmagnetized portion 131. The sealing portion 133 may comprise an elastic material. The sealing portion 133 may comprise one of silicone rubber, ethylene propylene diene monomer (EPDM) rubber, nitrile rubber, fluorosilicone rubber, fluororubber, natural rubber, polytetrafluoroethylene, polyurethane, neoprene rubber, and polycarbonate. Due to the elasticity of the sealing portion 133, a liquid seal can be provided within the internal space defined by the battery pack housing 110 and the cover when the gasket 130 is pressed by the battery pack housing 110 and the cover.

[0049] Next, in P120, the battery pack housing 110 and the spacer 130 can be assembled together using magnetic force. The spacer 130 can be assembled to the battery pack housing 110 by an assembly robot AR. The assembly robot AR may include a base RB, a robotic arm RA, and a gripper RG. As a non-limiting example, the assembly robot AR may be an articulated robot.

[0050] The base RB can support other components of the assembly robot AR. Therefore, it can provide stability to the assembly robot AR during the operation of other components of the assembly robot AR.

[0051] A robotic arm RA may include multiple actuators, multiple links, multiple joints, and multiple servo motors. The joints are components that enable the robotic arm RA to bend. The joints can be connected to each other via links. Each actuator may include a motor that controls the movement of the robotic arm RA and / or a hydraulic drive. The servo motors can precisely control the movement of the joints.

[0052] The gripper RG can be attached to the end of the robotic arm RA. The gripper RG may also be referred to as an end effector. The gripper RG may include an electromagnet. The gripper RG can be configured to apply a magnetic field to the pad 130. The gripper RG can apply a magnetic field to the pad 130 to grip the pad 130 and place the pad 130 downward on the upper surfaces 112U, 113U, 114U, and 115U of the sidewalls 112, 113, 114, and 115U.

[0053] Universal gaskets consist only of elastic material and require manual operation, thus the assembly process of universal gaskets with the battery pack housing is a barrier to automation. According to an embodiment, gasket 130 includes an unmagnetized portion 131 that can be lifted by an electromagnet. Therefore, gasket 130 can be assembled by an assembly robot AR including an electromagnet, and the assembly process of gasket 130 and battery pack housing 110 can be automated.

[0054] Next, in P120, residual magnetism of the pad 130 can be removed. According to an embodiment, the gripper RG can be configured to apply a coercive force to the unmagnetized portion 131 of the pad 130. According to an embodiment, the gripper RG can be configured to apply an alternating magnetic field to the unmagnetized portion 131 for demagnetizing the unmagnetized portion 131 of the pad 130. According to an embodiment, the gripper RG can be configured to apply a high-frequency pulsed magnetic field to the unmagnetized portion 131 of the pad 130.

[0055] According to the embodiment, demagnetizing the gasket 130 can prevent accelerated corrosion of the battery pack housing 110, interference with electronic components, and malfunction of the battery management system (BMS) caused by the residual magnetism of the gasket 130.

[0056] (Second Embodiment)

[0057] Figure 5 A gasket according to another embodiment is shown.

[0058] Figure 6 yes Figure 5 A cross-sectional view of the gasket.

[0059] Reference Figure 5 and Figure 6 The gasket 130' may include an unmagnetized portion 131' and a sealing portion 133'. The unmagnetized portion 131' may include the above-mentioned... Figure 4 The unmagnetized portion 131 is one of the materials listed. The sealing portion 133' may contain the materials mentioned above. Figure 4 The sealing part 133 is one of the materials listed.

[0060] The unmagnetized portion 131' can be partially inserted into the sealing portion 133'. The unmagnetized portion 131' may include a tongue 131T to be inserted into a groove 133G in the sealing portion 133'. Therefore, the unmagnetized portion 131' and the sealing portion 133' can be joined together by an interference fit method based on a tongue and groove.

[0061] The unmagnetized portion 131' can be exposed to the outside. The outer periphery of the unmagnetized portion 131' can be larger than the outer periphery of the sealing portion 133'. Therefore, when the gasket 130' is assembled to the battery pack housing 110 (see...), Figure 2 When the magnetized portion 131' is facing the outside of the battery pack housing 110, the unmagnetized portion 131' can face the outside of the battery pack housing 110.

[0062] (Third embodiment)

[0063] Figure 7 This is a plan view used to describe the battery pack 100 according to an embodiment.

[0064] Reference Figure 7 The battery pack 100 may include a battery pack housing 110, a battery cell assembly 120, and a gasket 130.

[0065] Battery pack housing 110 and gasket 130 are as shown above. Figures 1 to 4 The descriptions are essentially the same, so redundant descriptions are omitted here.

[0066] Multiple battery cell assemblies 120 may be located on a base plate 111 of the battery pack housing 110. The base plate 111 may support the multiple battery cell assemblies 120. Side walls 112, 113, 114 and 115 may be horizontally surrounding the multiple battery cell assemblies 120.

[0067] The intermediate beam 117 may be further disposed on the battery pack housing 110. The intermediate beam 117 may extend along the X-axis. The intermediate beam 117 may be inserted between the side walls 112 and 113. The intermediate beam 117 may be included in an intermediate plate, which is one of a plurality of unit plates joined together by friction stir welding. Therefore, the intermediate beam 117 may be formed together with the intermediate plate and is an integrally formed element with the intermediate plate.

[0068] Each of the multiple battery cell assemblies 120 may include multiple battery cells arranged along the X-axis, multiple pads, a first integrated circuit assembly, and a second integrated circuit assembly.

[0069] Each of the multiple battery cells may be a lithium-ion battery. Each of the multiple battery cells includes an electrode assembly, an electrolyte, and a battery cell housing. The battery cell housing may include an aluminum laminate, a cylindrical metal can, a prismatic metal can, or a combination of an aluminum laminate, a cylindrical metal can, and a prismatic metal can.

[0070] The electrode assembly included in the battery cell casing includes a positive electrode, a negative electrode, and a separator located between the positive and negative electrodes. The electrode assembly can be a wound-type electrode assembly or a stacked electrode assembly. A wound-type electrode assembly can include a structure in which the positive electrode, negative electrode, and separator located between the positive and negative electrodes are wound together. A stacked electrode assembly can include multiple positive electrodes and multiple negative electrodes sequentially stacked, and multiple separators located between the multiple positive electrodes and multiple negative electrodes. The positive electrode may include a positive current collector and a positive electrode active material. The negative electrode may include a negative current collector and a negative electrode active material.

[0071] Each of the multiple battery cells may include a positive electrode lead and a negative electrode lead. The positive and negative electrode leads can be collectively referred to as electrode leads. That is, an electrode lead can be either a positive electrode lead or a negative electrode lead. The positive electrode lead can be connected to the negative electrode terminal of the electrode assembly. The negative electrode lead can be connected to the negative electrode terminal of the electrode assembly.

[0072] Multiple battery cells can be arranged along the X-axis. Each of the multiple battery cells can be a bidirectional battery cell. Therefore, the positive and negative leads of each of the multiple battery cells can protrude from the battery cell casing in opposite directions. The positive and negative leads of each of the multiple battery cells can be spaced apart from each other along the Y-axis. The Y-axis can be substantially perpendicular to the X-axis. The direction substantially perpendicular to each of the X-axis and Y-axis will be defined as the Z-axis.

[0073] In the following description, the technical concept of this disclosure will be described with reference to an example where each of the plurality of battery cells is a bidirectional battery cell as described above. Based on the description herein, those skilled in the art will be able to readily derive embodiments where each of the plurality of battery cells is a unidirectional battery cell.

[0074] According to an embodiment, multiple battery cells can form multiple groups. Each of the multiple groups is a subgroup of battery cells that are connected in parallel with each other. The number of battery cells included in each of the multiple groups (i.e., the number of battery cells connected in parallel) can be determined based on the current to be output through the battery cell assembly 120.

[0075] In the following description, the technical concept of this disclosure will focus on examples where each of the multiple groups includes only one of the multiple battery cells (i.e., each of the multiple battery cells is a group). Based on the description herein, those skilled in the art will be able to readily derive examples of one or more groups including each of the multiple battery cells.

[0076] According to an embodiment, each of the plurality of pads may comprise polyurethane. According to an embodiment, each of the plurality of pads may comprise an elastic material. The plurality of pads can absorb the expansion of the plurality of battery cells. Two battery cells may be interposed between two adjacent pads of the plurality of pads, but the embodiment is not limited thereto. The thickness of each pad of the plurality of pads and the arrangement of the plurality of pads based on the plurality of battery cells can vary within a range that satisfies the expansion absorption conditions.

[0077] According to other embodiments, the plurality of pads may be thermal barriers. According to embodiments, each of the plurality of pads may have a high melting temperature and low thermal conductivity. When each of the plurality of pads is a thermal barrier, each of the plurality of pads may contain a flame-retardant material, such as ceramic or coated glass fiber.

[0078] A first integrated circuit assembly may be disposed at the front of each battery cell assembly 120. The first integrated circuit assembly may be integrated with multiple battery cells. The first integrated circuit assembly may include a first insulating frame, a first integrated circuit, a busbar, and an insulating cover.

[0079] The first insulating frame may contain insulating material. The first insulating frame may support the first integrated circuit and the busbar.

[0080] 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 lead of each odd-numbered battery cell and the negative lead of each even-numbered battery cell. The first integrated circuit may be configured to sense the voltage of a plurality of nodes consisting of multiple battery cells.

[0081] An insulating cover can be mounted on a first insulating frame. The insulating cover can be coupled to the first insulating frame via an interference fit. The insulating cover can cover the first integrated circuit. The insulating cover can contain insulating material.

[0082] The second integrated circuit assembly can be located at the rear of each battery cell assembly 120. The front of each battery cell assembly 120 can be opposite to the rear of each battery cell assembly 120. The second integrated circuit assembly can be spaced apart from the first integrated circuit assembly across multiple battery cells. The second integrated circuit assembly can be integrated into multiple battery cells. The negative electrode lead of each odd-numbered battery cell and the positive electrode lead of each even-numbered battery cell can be located on a second side.

[0083] The distance between the negative lead of each odd-numbered battery cell and the second integrated circuit assembly can be less than the distance between the negative lead of each odd-numbered battery cell and the first integrated circuit assembly.

[0084] The distance between the positive lead of each even-numbered battery cell and the second integrated circuit assembly can be less than the distance between the positive lead of each even-numbered battery cell and the first integrated circuit assembly.

[0085] The second integrated circuit assembly may include a second insulating frame, a second integrated circuit, and an insulating cover. The second insulating frame may contain insulating material. The second insulating frame may support the second integrated circuit and the insulating cover.

[0086] The second integrated circuit can be mounted on the second insulating frame. The second integrated circuit can be configured to be electrically connected to the negative lead of each odd-numbered battery cell and the positive lead of each even-numbered battery cell. The second integrated circuit can be configured to sense the voltage of multiple nodes composed of multiple battery cells.

[0087] The second insulating cover can be mounted on the second insulating frame. The second insulating cover can be coupled to the second insulating frame by an interference fit. The second insulating cover can contain insulating material. The second insulating cover can cover and protect the negative lead of each odd-numbered battery cell and the positive lead of each even-numbered battery cell.

[0088] Each battery cell assembly 120 may also include a flat flexible cable (FFC) assembly. The FFC assembly can connect the first integrated circuit and the second integrated circuit to each other. The voltage collected by the second integrated circuit can be transferred to the first integrated circuit through the FFC assembly.

[0089] exist Figure 7 In this configuration, the arrangement of multiple battery cell modules 120 can be a 2×2 array. Figure 7 The arrangement of the plurality of battery cell modules 120 is a non-limiting example and should not be construed as limiting the technical concept of this disclosure in any way. Based on the above description, those skilled in the art will be able to readily deduce the plurality of battery cell modules 120 arranged in a P×Q array (where P and Q are each integers greater than 1).

[0090] The battery pack 100 may also include a battery management system (BMS). The BMS can be configured to monitor, balance, and control the battery pack 100. Monitoring of the battery pack 100 may include measuring the voltage and current of specific nodes in the plurality of battery cell assemblies 120 and measuring the temperature at set locations within the battery pack 100.

[0091] Balancing the battery pack 100 is an operation to reduce deviations between the multiple battery cell assemblies 120. Control of the battery pack 100 includes preventing overcharging, over-discharging, and overcurrent. Through monitoring, balancing, and control, the battery pack 100 can operate under optimal conditions to prevent shortening of the lifespan of each of the multiple battery cell assemblies 120.

[0092] The battery pack 100 may also include covers attached to the sidewalls 112, 113, 114, and 115 of the battery pack housing 110. The covers may cover components inside the battery pack 100, such as battery cell assemblies 120 and electronic components. The covers may be secured to the battery pack housing 110 by mechanical means such as bolted connections.

[0093] The battery pack 100 may also include venting devices integrated into the sidewalls 114 and 115. One of the sidewalls 114 and 115 may include a vent hole connected to the venting device. The venting device may be configured to delay heat propagation by venting hot gases from the interior of the battery pack 100 to the exterior in the event of a thermal runaway event in any of the multiple cell assembly 120.

[0094] Here, the thermal runaway event of multiple battery cell modules 120 is an uncontrollable positive feedback state in which the temperature change of multiple battery cell modules 120 accelerates the temperature change. In the thermal runaway state, the temperature of the multiple battery cell modules 120 increases sharply, and a large amount of high-pressure gas and combustion debris are discharged from the multiple battery cell modules 120.

[0095] The battery pack 100 may also include additional electronic components, such as a cooling device, a power relay assembly (PRA), and a safety plug. The cooling device may include a cooling fan. The cooling fan circulates air within the battery pack 100 to prevent overheating of each of the multiple battery cell assemblies 120. The PRA can be configured to supply or disconnect power from the high-voltage battery to an external load (e.g., a vehicle's motor). When an abnormal voltage, such as a voltage surge, occurs, the PRA can disconnect the power supply to the external load (e.g., the vehicle's motor) to protect both the multiple battery cell assemblies 120 and the external load. Additional electronic components may be inserted between the multiple battery cell assemblies 120 and the sidewall 115. The space between the battery cell assemblies 120 and the sidewall 115 may be referred to as the electronic component mounting area.

[0096] The battery pack 100 may also include a plurality of intermediate busbars configured to electrically connect a plurality of battery cell assemblies 120. The plurality of battery cell assemblies 120 may be connected in series via the plurality of intermediate busbars. Therefore, the battery pack 100 may be configured to output a high voltage to an external load (e.g., a vehicle motor).

[0097] The present disclosure has been described in more detail above with reference to the accompanying drawings and embodiments. However, the configurations shown in the drawings or embodiments described in this specification are merely examples of the present disclosure and do not reflect all the technical concepts of the present disclosure. Therefore, it should be understood that various equivalents and modifications to these configurations have been made as of the date of filing of this application.

Claims

1. A method for manufacturing a secondary battery, comprising: Prepare a battery pack housing and a gasket, wherein the battery pack housing includes a base plate and sidewalls perpendicular to the base plate, and the gasket includes an unmagnetized portion and a sealing portion coupled to the unmagnetized portion; and The spacer assembly is assembled into the battery pack housing using magnetic force.

2. The method according to claim 1, wherein, The unmagnetized portion includes one of the following: iron, nickel, cobalt, steel, ferroalloys, soft iron, silicon steel, ferrite, μ metal, nickel-iron alloys, amorphous metals, and ultrapure aluminum.

3. The method according to claim 1, wherein, The sealing component comprises one of silicone rubber, ethylene propylene diene monomer (EPDM) rubber, nitrile rubber, fluorosilicone rubber, fluororubber, natural rubber, polytetrafluoroethylene, polyurethane, chloroprene rubber, and polycarbonate.

4. The method according to claim 1, wherein, The gasket is prepared by insert molding of the unmagnetized portion.

5. The method according to claim 1, wherein, The unmagnetized portion is embedded in the sealing portion.

6. The method according to claim 1, wherein, The sealing portion includes a groove, into which the tongue of the unmagnetized portion is inserted.

7. The method according to claim 6, wherein, The sealed portion and the unmagnetized portion are joined together by an interference fit.

8. The method of claim 1, further comprising removing residual magnetism from the gasket.

9. The method according to claim 8, wherein, The residual magnetism of the gasket is removed by coercivity.

10. The method according to claim 8, wherein, The residual magnetism of the gasket is removed by an alternating magnetic field.

11. The method according to claim 8, wherein, The residual magnetism of the gasket is removed by a high-frequency pulsed magnetic field.

12. A battery pack, comprising: A battery pack housing, the battery pack housing including a base plate and a side wall perpendicular to the base plate; Multiple battery cell assemblies are located on the base plate; as well as Gasket, the gasket being located on the sidewall, The gasket includes an unmagnetized portion and a sealing portion bonded to the unmagnetized portion.

13. The battery pack according to claim 12, wherein, The unmagnetized portion includes one of the following: iron, nickel, cobalt, steel, ferroalloys, soft iron, silicon steel, ferrite, μ metal, nickel-iron alloys, amorphous metals, and ultrapure aluminum.

14. The battery pack according to claim 12, wherein, The sealing component comprises one of silicone rubber, ethylene propylene diene monomer (EPDM) rubber, nitrile rubber, fluorosilicone rubber, fluororubber, natural rubber, polytetrafluoroethylene, polyurethane, chloroprene rubber, and polycarbonate.

Images