Battery Cell And Battery Module Including the same

Abstract

The present disclosure provides a battery cell comprising: an electrode assembly including a positive plate including a positive tab, a negative plate including a negative tab, and a separator; a cell case housing the electrode assembly; a cap plate assembly including a cap plate covering an open end of the cell case and an electrode terminal disposed on the cap plate; a current collector electrically connecting the electrode assembly and the electrode terminal; and a pad member coupled to the cap plate assembly; wherein the pad member includes an avoidance portion for avoiding at least a portion of the current collector.

Description

Technology Field

[0001] The present disclosure relates to a battery cell (secondary battery) comprising a pad member and a battery module comprising the same. Background Technology

[0002] Unlike primary batteries, secondary batteries (secondary battery cells) are capable of charging and discharging, and are used as power sources in various fields such as digital cameras, mobile devices, electric vehicles, and energy storage systems (ESS). These secondary batteries come in various types, including lithium-ion batteries, nickel-cadmium batteries, and nickel-metal hydride batteries, and can be manufactured as flexible pouch-type battery cells or rigid can-type battery cells. Can-type battery cells are classified according to their external shape into prismatic battery cells, cylinder battery cells, and coin-type battery cells, and each form can be applied in various ways to suit the devices and environments in which they are used.

[0003] Multiple battery cells can be formed into a stacked cell assembly. The cell assembly is placed inside a module housing to form a battery module, and multiple battery modules can be placed inside a pack frame to form a battery pack. The problem to be solved

[0004] A battery cell may include a current collector and a cap plate assembly. When the current collector and the cap plate assembly are combined, a dead space, which is an unused area within the battery cell, may be created. If a dead space is created, the electrolyte may be used inefficiently. Furthermore, the dead space may reduce the durability of the battery cell.

[0006] According to one aspect of the present disclosures, a battery cell capable of reducing dead space within the battery cell and a battery module including the same can be provided.

[0007] According to one aspect of the present disclosure, a battery cell that efficiently uses an electrolyte and a battery module including the same can be provided.

[0008] According to one aspect of the present disclosure, a highly durable battery cell and a battery module including the same can be provided.

[0010] The battery cell of the present disclosure and the battery module including the same can be widely applied in green technology fields such as electric vehicles, battery charging stations, and other applications utilizing batteries, such as solar power generation and wind power generation. Furthermore, the battery cell of the present disclosure and the battery module including the same can be used in eco-friendly electric vehicles, hybrid vehicles, etc., to prevent climate change by suppressing air pollution and greenhouse gas emissions. means of solving the problem

[0011] A battery cell according to the present disclosure comprises: an electrode assembly comprising a positive plate including a positive tab, a negative plate including a negative tab, and a separator; a cell case accommodating the electrode assembly; a cap plate assembly comprising a cap plate covering an open end of the cell case and an electrode terminal disposed on the cap plate; a current collector electrically connecting the electrode assembly and the electrode terminal; and a pad member coupled to the cap plate assembly; wherein the pad member may include an avoidance portion for avoiding at least a portion of the current collector.

[0012] According to one embodiment, the cap plate includes a vent portion, and the pad member may include an opening having a shape corresponding to the vent portion.

[0013] According to one embodiment, the current collector includes a first portion that is coupled to the cap plate assembly, and the thickness of the pad member may be 50% or more of the thickness of the first portion and 100% or less of the thickness of the first portion.

[0014] According to one embodiment, the pad member may include a synthetic rubber material.

[0015] According to one embodiment, the synthetic rubber material may include at least one of neoprene, butyl, and ethylene propylene diene monomer (EPDM).

[0016] According to one embodiment, the pad member can be bonded to the cap plate using an adhesive.

[0017] According to one embodiment, the pad member may be coupled to the cap plate while the current collector is coupled to the cap plate assembly.

[0018] According to one embodiment, the current collector includes a first portion coupled to the cap plate assembly and a second portion coupled to the positive tab or the negative tab, and the avoidance portion may have a shape for avoiding the first portion.

[0019] According to one embodiment, the current collector may include a bent portion having a bent shape.

[0020] According to one embodiment, the positive electrode tab is disposed on one side of the first direction of the electrode assembly, the negative electrode tab is disposed on the other side of the first direction of the electrode assembly, and the electrode terminal is disposed on one side of the second direction of the electrode assembly, and the second direction may be a direction perpendicular to the first direction.

[0021] According to one embodiment, the current collecting member includes a first portion that is coupled to the cap plate assembly, and the avoidance portion of the pad member has a shape corresponding to the first portion of the current collecting member, and the pad member can be coupled to at least a portion of the area of ​​the cap plate assembly where the current collecting member is not coupled.

[0022] According to one embodiment, the current collector includes an anode current collector and a cathode current collector, wherein the anode current collector is arranged to cover at least a portion of one side in a first direction and one side in a second direction of the electrode assembly, and the cathode current collector may be arranged to cover at least a portion of the other side in a first direction and one side in a second direction of the electrode assembly.

[0023] According to one embodiment, the positive electrode tab and the negative electrode tab may be positioned opposite the electrode terminal.

[0024] According to one embodiment, the current collector includes a second portion that is coupled to the positive tab or the negative tab, and the current collector may be coupled to the positive tab or the negative tab while at least a portion of the second portion is covered by the positive tab or the negative tab.

[0025] According to one embodiment, the current collector can be joined to the positive tab or the negative tab through welding.

[0026] A battery module according to the present disclosure comprises: a plurality of battery cells; and a module housing for accommodating the plurality of battery cells; wherein at least one of the plurality of battery cells comprises: an electrode assembly comprising a positive plate including a positive tab, a negative plate including a negative tab, and a separator; a cell case for accommodating the electrode assembly; a cap plate assembly comprising a cap plate covering an open end of the cell case and an electrode terminal disposed on the cap plate; a current collector electrically connecting the electrode assembly and the electrode terminal; and a pad member coupled to the cap plate assembly; wherein the pad member may include an avoidance portion for avoiding at least a portion of the current collector. Effects of the invention

[0028] According to one embodiment of the present disclosure, the dead space inside the battery cell can be reduced.

[0029] According to one embodiment of the present disclosure, the electrolyte inside the battery cell can be used efficiently.

[0030] According to one embodiment of the present disclosure, the durability of the battery cell can be improved. Brief explanation of the drawing

[0032] FIG. 1 is a perspective view of a battery cell according to a first embodiment. Figure 2 is an exploded perspective view of the battery cell shown in Figure 1. FIG. 3 is an exploded perspective view of the cap plate assembly, current collector, and pad member shown in FIG. 1. FIG. 4 is a perspective view illustrating the state in which the electrode tab and the current collector are combined in the battery cell shown in FIG. 1. FIG. 5 is a bottom perspective view showing the combined state of the cap plate assembly and the current collector member shown in FIG. 1. FIG. 6 is a bottom perspective view showing the state in which a pad member is coupled to a cap plate assembly coupled with a current collector member shown in FIG. 5. FIG. 7 is a bottom perspective view showing the combined state of the cap plate assembly, the current collector, and the pad member. Figure 8 is a cross-sectional view along line II' shown in Figure 1. FIG. 9 is an exploded perspective view of a battery cell according to a second embodiment. FIG. 10 is a bottom perspective view showing the combined state of the cap plate assembly and the current collector shown in FIG. 9. FIG. 11 is a bottom perspective view illustrating the state in which a pad member is attached to a cap plate assembly to which a current collector member shown in FIG. 10 is attached. FIG. 12 is a perspective view of a battery module according to one embodiment. Specific details for implementing the invention

[0033] Identical reference numbers or symbols in each drawing attached to this specification represent parts or components that perform substantially the same function. For convenience of explanation and understanding, the same reference numbers or symbols may be used to describe different embodiments. That is, even if components having the same reference number are depicted in multiple drawings, the multiple drawings do not all represent a single embodiment.

[0034] In the following description, singular expressions include plural expressions unless the context clearly indicates otherwise. Terms such as "comprising" or "constituting" are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0035] In addition, it should be noted in advance that expressions such as upper side, top, lower side, bottom, side, front, and rear in the following description are based on the direction depicted in the drawings, and may be expressed differently if the direction of the object changes.

[0036] Additionally, in this specification and claims, terms including ordinal numbers, such as "first," "second," etc., may be used to distinguish between components. These ordinal numbers are used to distinguish identical or similar components from one another, and the meaning of the terms should not be limited by the use of such ordinal numbers. For example, the order of use or arrangement of components combined with such ordinal numbers should not be limited by the number. If necessary, each ordinal number may be used interchangeably.

[0037] Hereinafter, the present disclosure will be described in detail with reference to the attached drawings. However, this is merely an example and the present disclosure is not limited to the specific embodiments described illustratively.

[0039] A battery cell (100) according to a first embodiment of the present disclosure will be described with reference to FIGS. 1 to 3.

[0040] FIG. 1 is a perspective view of a battery cell (100) according to a first embodiment, FIG. 2 is an exploded perspective view of the battery cell (100) shown in FIG. 1, and FIG. 3 is an exploded perspective view of the cap plate assembly (130), current collector (140), and pad member (150) shown in FIG. 1.

[0041] Referring to FIGS. 1 to 3, a battery cell (100) according to the first embodiment of the present disclosure may include an electrode assembly (110), a cell case (120), a cap plate assembly (130), a current collector (140), and a pad member (150).

[0042] The battery cell (100) of the present disclosure may be composed of a secondary battery capable of charging and discharging. The battery cell (100) may have a form in which an electrode assembly (110) and an electrolyte (not shown) are housed inside a cell case (120) that forms an outer casing. As an example, the battery cell (100) may be composed of a lithium-ion (Li-ion) battery or a nickel-metal hydride (Ni-MH) battery, but the types are not limited thereto.

[0043] The battery cell (100) may have a form in which an electrode assembly (110) and an electrolyte are contained within a cell case (120) that forms an outer casing.

[0044] The electrode assembly (110) may include a positive plate (111) including a positive tab (111a), a negative plate (112) including a negative tab (112a), and a separator (113). The electrode assembly (110) may include a positive plate (111) (cathode plate), a negative plate (112) (anode plate), and a separator (113). The separator (113) may be interposed between the positive plate (111) and the negative plate (112) to electrically insulate the positive plate (111) and the negative plate (112). The electrode assembly (110) may have various forms, such as a winding type, a stacking type, a zigzag-folding type, or a stack-folding type.

[0045] The electrode plate may include an anode plate (111) and a cathode plate (112). The anode plate (111) and the cathode plate (112) may have a structure in which an active material is coated on a metal foil. The anode plate (111) and the cathode plate (112) may each include a blank area where no active material is coated. The anode tab (111a) and the cathode tab (112a) may each include a blank area where no active material is coated.

[0046] The electrode plate may include electrode tabs. The electrode tabs may have a shape extending from the electrode plate. The electrode tabs may include an anode tab (111a) provided on the anode plate (111) and a cathode tab (112a) provided on the cathode plate (112). The electrode tabs may be disposed at each end of the first direction (X) of the electrode assembly (110). As an example, the anode tab (111a) may be disposed on one side of the first direction (X) of the electrode assembly (110), and the cathode tab (112a) may be disposed on the other side of the first direction (X) of the electrode assembly (110). However, the placement position of the electrode tabs is not limited thereto. For example, the electrode tabs may be disposed facing the electrode terminal (135) as shown in FIG. 9.

[0047] The cell case (120) can accommodate an electrode assembly (110). The cell case (120) has an internal receiving space and may have an end (C) that is open at one end. The cell case (120) may have an end (C) (e.g., the upper side) in a second direction (Z) that is perpendicular to the first direction (X) open. The electrode assembly (110) can be accommodated in the receiving space of the cell case (120). The electrode assembly (110) can be accommodated in the cell case (120) through the open end (C) of the cell case (120).

[0048] The cell case (120) may have a flat and angular cuboid shape, but the shape is not limited thereto. The cell case (120) may be formed of aluminum or a material containing aluminum, but the material of the cell case (120) is not limited thereto.

[0049] The cap plate assembly (130) may include a cap plate (131) covering an open end (C) of a cell case (120) and an electrode terminal (135) disposed on the cap plate (131). The cap plate assembly (130) may cover an open end (C) of the cell case (120). The cap plate (131) may cover an open end (C) of the cell case (120). The cap plate (131) may be combined with the cell case (120) to form a space in which an electrode assembly (110) is received. The cap plate (131) may be formed of aluminum or a material containing aluminum, but the material of the cap plate (131) is not limited thereto. The electrode terminal (135) may be disposed on the cap plate (131). The electrode terminal (135) may be electrically connected to the electrode plate. The electrode terminal (135) can be electrically connected to the electrode plate through the current collector (140). The electrode terminal (135) may include a positive terminal electrically connected to the positive plate (111) and a negative terminal electrically connected to the negative plate (112).

[0050] The current collector (140) can electrically connect the electrode tab and the electrode terminal (135). The current collector (140) can be joined to the electrode terminal (135) and the electrode tab, respectively, by known joining methods such as welding. The joining of the current collector (140) and the electrode terminal (135) may utilize laser welding, ultrasonic welding, screw joining, bolt joining, rivet joining, snap joining, etc., but the joining method is not limited thereto.

[0051] Referring to FIG. 3, the current collector (140) may include a bent portion (143) having a bent shape.

[0052] If the electrode tab and the cap plate assembly (130) are not arranged in the same direction, the electrode tab and the electrode terminal (135) may be connected through a bent portion (143) having a bent shape. For example, if the cell case (120) has an open shape in the second direction (Z) perpendicular to the first direction (X), and the electrode tabs are each arranged at both ends of the electrode assembly (110) in the first direction (X), the current collector (140) may be electrically connected to the electrode tab facing in the first direction (X) and electrically connected to the electrode terminal (135) facing in the second direction (Z). In this case, the current collector (140) may have an 'L'-shaped bent form.

[0053] The current collector (140) may include a first part (141) coupled to the cap plate assembly (130) and a second part (142) coupled to the positive tab (111a) or the negative tab (112a). The current collector (140) may be coupled to the cap plate assembly (130). The first part (141) of the current collector (140) may be coupled to the cap plate assembly (130). The current collector (140) may be connected to an electrode terminal (135) disposed on the cap plate (131). The first part (141) of the current collector (140) may be coupled to the electrode terminal (135) connected to the cap plate assembly (130). The second part (142) of the current collector (140) may be coupled to the positive tab (111a) or the negative tab (112a).

[0054] The first part (141) may have a shape extending in a first direction (X) so as to be coupled with the cap plate assembly (130). The second part (142) may have a shape extending in a second direction (Z) so as to be coupled with the positive tab (111a) or the negative tab (112a). The first part (141) and the second part (142) may be connected through a bend (143).

[0055] The battery cell (100) may additionally include an insulating member (160). The insulating member (160) may be positioned between the current collector (140) and the electrode plate to electrically insulate the current collector (140) and the electrode plate. The insulating member (160) may be combined with a part of the current collector (140) so that the current collector (140) is electrically connected to the electrode tab only at a specific part. One side of the insulating member (160) may be in contact with the current collector (140). The other side of the insulating member (160) may be positioned spaced apart from the electrode plate or positioned to be in contact with the electrode plate. The insulating member (160) may include an insulating material. For example, the insulating member (160) may be formed from a material including polypropylene. However, it is not limited thereto and may be formed from various materials capable of electrical insulation. The insulating member (160) may have a shape corresponding to at least a part of the current collecting member (140), but is not limited thereto and can be modified in various ways.

[0056] The pad member (150) may be coupled to the cap plate assembly (130). The pad member (150) may include an avoidance portion (151) for avoiding at least a portion of the current collecting member (140). The pad member (150) may include an avoidance portion (151) for avoiding the area where the current collecting member (140) and the cap plate assembly (130) are coupled. That is, a certain area of ​​the cap plate assembly (130) may be coupled with the current collecting member (140), and the remaining area may be coupled with the pad member (150). The pad member (150) may include an avoidance portion (151) so as not to prevent the coupling of the current collecting member (140) and the cap plate assembly (130). The pad member (150) may have an avoidance portion (151) so as not to interfere with the current collecting member (140).

[0057] The avoidance portion (151) of the pad member (150) may have a shape for avoiding the first portion (141) of the current collecting member (140). The avoidance portion (151) of the pad member (150) may have a shape for avoiding the first portion (141), which is the part where the cap plate (131) and the current collecting member (140) are joined. A certain area of ​​the cap plate (131) may be joined to the first portion (141) of the current collecting member (140), and a certain area of ​​the cap plate (131) may be joined to the pad member (150).

[0058] The current collecting member (140) may include a first part (141) that is coupled to the cap plate assembly (130). The avoidance part (151) of the pad member (150) has a shape corresponding to the first part (141) of the current collecting member (140), and the pad member (150) may be coupled to at least a portion of the area of ​​the cap plate assembly (130) where the current collecting member (140) is not coupled. The avoidance part (151) may have a shape corresponding to the first part (141) of the current collecting member (140). For example, the avoidance part (151) may have a shape that interlocks with the first part (141) of the current collecting member (140). The avoidance part (151) may be formed in a shape and position corresponding to the current collecting member (140). The pad member (150) can be coupled to an area of ​​the lower surface of the cap plate (131) where the first part (141) is not coupled. In other words, a certain area of ​​the lower surface of the cap plate (131) is coupled to the first part (141) of the current collector (140), and the remaining area can be coupled to the pad member (150).

[0060] Hereinafter, with reference to FIG. 4, the combination of the current collector (140) and the electrode assembly (110) will be explained.

[0061] FIG. 4 is a perspective view showing the state in which the electrode tab and the current collector (140) are combined in the battery cell (100) shown in FIG. 1.

[0062] The electrode tabs may be positioned in various directions of the electrode assembly (110). As an example, the positive electrode tab (111a) may be positioned on one side of the first direction (X) of the electrode assembly (110), and the negative electrode tab (112a) may be positioned on the other side of the first direction (X) of the electrode assembly (110). As another example, the electrode tabs may be positioned to face the electrode terminals as shown in FIG. 9. The direction in which the electrode tabs are positioned may be appropriately modified according to the structural characteristics of the battery cell (100) or the manufacturing process. The battery cell (100) may include a bidirectional battery cell (100) in which the electrode terminals are positioned on both sides of a specific direction of the electrode assembly (110), and a unidirectional battery cell (100) in which the electrode terminals are positioned on one side of a specific direction of the electrode assembly (110). A bidirectional battery cell (100) may include an electrode assembly (110) in which electrode tabs are respectively disposed on both sides of a specific direction of the electrode assembly (110), and a unidirectional battery cell (100) may include an electrode assembly (110) in which electrode tabs are disposed on one side of a specific direction of the electrode assembly (110). In this case, the electrode assembly (110) in which electrode tabs are respectively disposed on both sides of a specific direction of the electrode assembly (110) and the electrode assembly (110) in which electrode tabs are disposed on one side of a specific direction of the electrode assembly (110) need to be manufactured using different equipment.

[0063] When the current collector (140) includes a bend portion (143), a unidirectional battery cell (100) can be manufactured using an electrode assembly (110) in which electrode tabs are respectively placed on both sides of a specific direction of the electrode assembly (110). When the current collector (140) includes a bend portion (143), a unidirectional battery cell (100) can be manufactured using an electrode assembly (110) manufacturing facility in which electrode tabs are respectively placed on both sides of a specific direction of the electrode assembly (110). A unidirectional battery cell (100) can be manufactured in which electrode tabs are placed on both sides of the electrode assembly (110), electrode terminals (135) are placed in a direction perpendicular to the electrode tabs, and the electrode terminals (135) and electrode tabs are connected through a current collector (140) including a bend portion (143). For example, the positive electrode tab (111a) may be positioned on one side of the first direction (X) of the electrode assembly (110), the negative electrode tab (112a) may be positioned on the other side of the first direction (X) of the electrode assembly (110), and the electrode terminal (135) may be positioned on one side of the second direction (Z) of the electrode assembly (110). The second direction (Z) may be a direction perpendicular to the first direction (X). In this case, the electrode terminal (135) and the electrode tab may be connected through a current collector member (140) including a bent portion (143).

[0064] The first direction (X) and the second direction (Z) may be directions perpendicular to each other. For example, if the first direction (X) is the length direction of the battery cell (100), the second direction (Z) may be the height direction of the battery cell (100).

[0065] The current collector (140) includes an anode current collector (140a) and a cathode current collector (140b), the anode current collector (140a) is positioned to cover at least a portion of one side of the first direction (X) and one side of the second direction (Z) of the electrode assembly (110), and the cathode current collector (140b) can be positioned to cover at least a portion of the other side of the first direction (X) and one side of the second direction (Z) of the electrode assembly (110).

[0066] The positive current collector (140a) can electrically connect the positive tab (111a) and the positive terminal, and the negative current collector (140b) can electrically connect the negative tab (112a) and the negative terminal. The positive current collector (140a) can cover at least a portion of one side (-X) in the first direction and one side (+Z) in the second direction of the electrode assembly (110). The negative current collector (140b) can cover at least a portion of one side (+X) in the first direction and one side (+Z) in the second direction of the electrode assembly (110). That is, the second part (142) of the positive current collector (140a) may cover at least a portion of one side (-X) in the first direction of the electrode assembly (110), and the second part (142) of the negative current collector (140b) may cover at least a portion of the other side (+X) in the first direction of the electrode assembly (110). The first part (141) of the positive current collector (140a) may cover at least a portion of one side (+Z) in the second direction of the electrode assembly (110), and the first part (141) of the negative current collector (140b) may cover at least a portion of one side (+Z) in the second direction of the electrode assembly (110).

[0067] The current collector (140) may include a second part (142) that is coupled to the positive tab (111a) or the negative tab (112b). The current collector (140) may be coupled to the positive tab (111a) or the negative tab (112a) with at least a portion of the second part (142) being covered by the positive tab (111a) or the negative tab (112a).

[0068] The electrode tab can be connected to the current collector (140) while covering at least a portion of the second part (142). The positive electrode tab (111a) can be connected to the positive current collector (140a) while covering at least a portion of the second part (142). The negative electrode tab (112a) can be connected to the negative current collector (140b) while covering at least a portion of the second part (142). The first part (141) of the current collector (140) is connected to the electrode terminal (135), and the second part (142) of the current collector (140) can be connected to the electrode tab. When combined while at least a portion of the second part (142) is covered by the electrode tab, the second part (142) may not require a shape for connection, such as a protrusion. When a protruding connection part is located on the current collector (140), the electrode tab may be partially cut to avoid the connection part. However, the electrode tab of the present disclosure may not be cut because it is not obstructed by the connection part during the process of connecting to the current collector (140). Therefore, the electrode tab cutting step can be omitted during the process of manufacturing the battery cell (100), and manufacturing costs can be reduced.

[0069] The current collector (140) can be joined to the positive tab (111a) or negative tab (112a) by welding. The second part (142) of the current collector (140) and the electrode tab of the electrode assembly (110) can be connected by welding. Laser welding or ultrasonic welding methods may be applied to the joining of the current collector (140) and the positive tab (111a) or negative tab (112a). However, in addition to laser welding and ultrasonic welding, any joining method capable of electrically connecting the electrode tab and the current collector (140) may be applied.

[0071] Hereinafter, the pad member (150) of the present disclosure will be described in more detail with reference to FIGS. 5 to 8.

[0072] FIG. 5 is a bottom perspective view showing the state in which the cap plate assembly (130) and the current collector (140) shown in FIG. 1 are combined, FIG. 6 is a bottom perspective view showing the state in which a pad member (150) is combined with the cap plate assembly (130) with the current collector (140) shown in FIG. 5, FIG. 7 is a bottom perspective view showing the state in which the cap plate assembly (130), the current collector (140), and the pad member (150) are combined, and FIG. 8 is a cross-sectional view along line II' shown in FIG. 1.

[0073] Referring to FIG. 5, a current collector (140) can be coupled with a cap plate assembly (130). One side of the current collector (140) can be coupled with the cap plate assembly (130). The current collector (140) can be connected to an electrode terminal (135) disposed on the cap plate (131). When the current collector (140) is coupled to the cap plate assembly (130), a step may occur in the cap plate assembly (130). Such a step may create a dead space in which energy cannot be stored in the battery cell (100). If a dead space is created inside the battery cell (100), the energy density of the battery cell (100) may be impaired. Additionally, if a dead space is created, the electrolyte may be overfilled. The pad member (150) can be bonded to the cap plate assembly (130) to overcome the step difference caused by the current collector (140). The pad member (150) can be coupled to the cap plate assembly (130) to reduce the dead space caused by the current collector (140). The pad member (150) can be coupled to the cap plate assembly (130) to reduce the dead space filled with electrolyte.

[0074] Referring to FIG. 6, the pad member (150) can be attached to the lower surface of the cap plate assembly (130). Since the pad member (150) is configured to reduce dead space, it may not be attached to the part where the current collecting member (140) is attached. The pad member (150) may be placed in the part where the current collecting member (140) is not attached. The pad member (150) may include an avoidance portion (151) for avoiding at least a part of the current collecting member (140) in order to eliminate the step difference caused by the current collecting member (140).

[0075] In the absence of the pad member (150), the area where the cap plate (131) and the current collector (140) are not joined may have a thinner thickness than the area where the cap plate (131) and the current collector (140) are joined. In this case, the area where the current collector (140) is not joined may be easily deformed by impact or load. The pad member (150) can reinforce this area to increase physical strength and strengthen the durability of the entire battery cell (100). By adding the pad member (150) to the vulnerable area of ​​the battery cell (100), the thickness of the battery cell (100) can be made uniform.

[0076] The pad member (150) can be coupled to the cap plate assembly (130). The coupling method between the pad member (150) and the cap plate assembly (130) can be implemented in various ways considering process efficiency and stability. For example, the pad member (150) can be formed integrally with the cap plate (131) by insert injection, etc. In this case, the coupling process between the pad member (150) and the cap plate (131) can be omitted. When the pad member (150) and the cap plate (131) are formed integrally, the manufacturing process can be simplified. In addition, the defect rate that may occur during the coupling process can be reduced.

[0077] As another example, the pad member (150) can be bonded to the cap plate assembly (130). The pad member (150) can be bonded to the cap plate assembly (130) using an adhesive. The adhesive may include a bond. The adhesive may include acetonitrile and polyethylene oxide (PEO) or acetone and polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) as components. The adhesive can secure the bonding strength between the cap plate (131) and the pad member (150). When the pad member (150) is bonded to the cap plate assembly (130) using an adhesive, the manufacturing cost can be further reduced.

[0078] The pad member (150) can be attached to the cap plate (131) while the current collector (140) is attached to the cap plate assembly (130). That is, the pad member (150) can be attached to the cap plate (131) after the current collector (140) is attached to the cap plate assembly (130). In this case, damage to the pad member (150) can be prevented during the process of attaching the current collector (140) to the cap plate assembly (130). For example, if the current collector (140) is welded to the cap plate assembly (130), heat and pressure can be prevented from being directly transferred to the pad member (150).

[0079] The pad member (150) may include a synthetic rubber material. The pad member (150) may include a synthetic rubber material capable of cushioning impact without any change in composition due to the electrolyte. When the pad member (150) includes a synthetic rubber material, deterioration or physical deformation of the material due to the electrolyte can be prevented. The synthetic rubber material can maintain stable physical properties as no chemical reaction or decomposition occurs even when in contact with the electrolyte. In addition, the material may not deform or its performance may not degrade even in a high-temperature environment. As a result, when the pad member (150) includes a synthetic rubber material, the lifespan of the battery cell (100) can be extended. As an example, the synthetic rubber material may include at least one of neoprene, butyl, and ethylene propylene diene monomer (EPDM).

[0080] The pad member (150) can mitigate shock or vibration that may occur inside the battery cell (100). The pad member (150) can improve the stability of the battery cell (100) by absorbing shock that occurs outside the battery cell (100). If shock or vibration is repeatedly applied, physical damage or positional change occurs in internal components of the battery cell (100), such as the electrode assembly (110) or the current collector (140). The pad member (150) can prevent performance degradation of the battery cell (100) by absorbing such shock and maintaining the physical stability of the internal components.

[0081] Referring to FIG. 3 and FIG. 8 together, the cap plate (131) may include a vent portion (132), and the pad member (150) may include an opening (152) having a shape corresponding to the vent portion (132).

[0082] A vent portion (132) may be disposed in at least one of the cell case (120) and the cap plate assembly (130). As an example, the vent portion (132) may be installed in the cap plate (131). The vent portion (132) may be installed in a vent hole (131a) formed in the cap plate (131). The vent portion (132) may be fixed to the cap plate (131) by laser welding or the like. The vent portion (132) may be configured to discharge gas, etc. generated in the receiving space of the cell case (120). For example, the vent portion (132) may be configured to break when the internal pressure of the cell case (120) rises due to gas, etc. Various changes are possible regarding the installation location and number of vents. For example, the vent portion (132) may be installed in the cell case (120).

[0083] The pad member (150) may include an opening (152) having a shape corresponding to the vent portion (132). The pad member (150) may include an opening (152) having a shape corresponding to the vent portion (132) so as not to obstruct the discharge of gas generated in the receiving space of the cell case (120).

[0084] The thickness of the pad member (150) may be 50% or more of the thickness of the first part (141) and 100% or less of the thickness of the first part (141).

[0085] If the thickness of the pad member (150) becomes equal to the thickness of the first part (141), the occurrence of dead space in the battery cell (100) can be minimized. If the thickness of the pad member (150) becomes equal to the thickness of the first part (141), the first part (141) of the current collector (140) and the pad member (150) can form a flat plane. In this case, the step difference caused by the current collector (140) is eliminated, and the dead space can be minimized. If the thickness of the pad member (150) exceeds 100% of the thickness of the first part (141), it may hinder the connection between the current collector (140) and the electrode assembly (110). If the thickness of the pad member (150) is 50% or less of the thickness of the first part (141), there may be a limit to effectively reducing the dead space.

[0086] Additionally, if the thickness of the pad member (150) is 50% or more of the thickness of the first part (141), it can contribute to optimizing the discharge path of gas generated inside the battery cell (100). In order for the gas to be discharged to the vent part (132) through an efficient path, the thickness of the vent part (132) needs to be thinner than the thickness of other areas. The vent part (132) can be designed to break first when the internal pressure of the cell case (120) rises due to gas, etc. To this end, when designing the cap plate (131), the thickness around the vent part (132) can be set to be thicker than the vent part (132).

[0087] The current collector (140) and pad member (150) of the present disclosure can provide the effect of increasing the thickness of the cap plate (131). Through the pad member (150) of the present disclosure, it is possible to design the system so that gas can be efficiently discharged to the vent portion (132) without separately adjusting the thickness of the cap plate (131). For example, the thickness of the vent portion (132) is maintained to be the same as the thickness of the cap plate (131), but the thickness of the periphery of the vent portion (132) can be relatively thickened by adding the thickness of the current collector (140) or the pad member (150) to the thickness of the cap plate (131). Therefore, the thicker the pad member (150), the more the gas discharge path can be optimized.

[0088] In addition, the pad member (150) can improve shock absorption and structural stability. The pad member (150) can protect the battery cell (100) from external shocks or vibrations.

[0090] With reference to FIGS. 9 to 11, a battery cell (100) according to a second embodiment will be described.

[0091] FIG. 9 is an exploded perspective view of a battery cell (100) according to a second embodiment, FIG. 10 is a bottom perspective view showing the state in which the cap plate assembly (130) and the current collector (140) shown in FIG. 9 are combined, and FIG. 11 is a bottom perspective view showing the state in which a pad member is combined with the cap plate assembly (130) to which the current collector (140) shown in FIG. 10 is combined.

[0092] Compared to the battery cell (100) according to the first embodiment described with reference to FIGS. 1 to 8, the battery cell (100) according to the second embodiment shown in FIGS. 9 to 11 has a difference in that the positive tab (111a) and the negative tab (112a) are arranged opposite the electrode terminal (135).

[0093] In the battery cell (100) according to the second embodiment, the positive tab (111a) and the negative tab (112a) may be positioned opposite the electrode terminal (135).

[0094] The description of the electrode assembly (110), cell case (120), cap plate assembly (130), current collector (140), pad member (150), and insulating member (160) described with reference to FIGS. 1 to 8, excluding differences, may be applied to the battery cell (100) according to the second embodiment.

[0095] The positive tab (111a) and the negative tab (112a) may be positioned opposite the electrode terminal (135). For example, if the electrode terminal (135) is positioned on one side of the second direction (Z) of the electrode assembly (110), the positive tab (111a) and the negative tab (112a) may be positioned on one side of the second direction (Z) of the electrode assembly (110). The current collector (140) may electrically connect the electrode terminal (135) and the electrode tab. The current collector (140) may be positioned at a location corresponding to the electrode tab. The current collector (140) may have a shape extending in the first direction (X). The avoidance portion (151) of the pad member (150) may be formed to avoid interference with the current collector (140). The avoidance portion (151) of the pad member (150) may have a shape corresponding to the current collecting member (140). The avoidance portion (151) of the pad member (150) may be formed at a position corresponding to the current collecting member (140).

[0097] Referring to FIG. 12, the battery module (200) will be described.

[0098] FIG. 12 is an exploded view of a battery module (200) according to one embodiment.

[0099] A battery module (200) may include a plurality of battery cells (210) and a module housing (220) that accommodates the plurality of battery cells (210). At least one of the plurality of battery cells (210) may include an electrode assembly (110), a cell case (120), a cap plate assembly (130), a current collector (140), and a pad member (150). The electrode assembly (110) may include a positive plate (111) including a positive tab (111a), a negative plate (112) including a negative tab (112a), and a separator (113). The cell case (120) may accommodate the electrode assembly (110). The cap plate assembly (130) may include a cap plate (131) covering an open end (C) of a cell case (120) and an electrode terminal (135) disposed on the cap plate (131). A current collector (140) may electrically connect the electrode assembly (110) and the electrode terminal (135). A pad member (150) may be coupled to the cap plate assembly (130). The pad member (150) may include an avoidance portion (151) for avoiding at least a portion of the current collector (140).

[0100] The description of the electrode assembly (110), cell case (120), cap plate assembly (130), current collector (140), pad member (150), and insulating member (160) described with reference to FIGS. 1 to 11 can be applied to each of the plurality of battery cells (210) included in the battery module (200) according to the present disclosure.

[0101] The module housing (220) may have a shape that covers at least a portion of the cell assembly. The module housing (220) may form at least a portion of the exterior of the battery module (200).

[0102] The module housing (220) may have various shapes or divided structures. As an example, the module housing (220) may be configured to include a housing body (221) having a cross-sectional shape with one side open, and a housing cover (225) that is joined with the housing body (221) to form an internal space. The housing cover (225) may cover the top surface of the cell assembly.

[0103] A cell assembly may be disposed on the inner side of the module housing (220). At least one surface constituting the module housing (220) may function as a heat dissipation plate to release heat generated from the battery cell (100) to the outside. At least a portion of the module housing (220) may be made of a material with high thermal conductivity, such as metal. For example, the module housing (220) may include aluminum. However, the material of the module housing (220) is not limited thereto, and various materials may be used as long as they have strength and thermal conductivity similar to metal, even if they are not metal.

[0105] The above description is merely an example of applying the principles of the present disclosure, and other configurations may be included without departing from the scope of the present disclosure. Additionally, some components of the aforementioned embodiments may be omitted, and each embodiment may be combined with one another. Explanation of the symbols

[0107] 100: Battery cell 110: Electrode assembly 111: Anode plate 111a: Anode tab 112: Cathode plate 112a: Cathode tab 113: Separator 120: Cell case 130: Cap plate assembly 131: Cap plate 131a: Vent hole 132: Vent section 135: Electrode terminal 140: Current collector 140a: Positive current collector 140b: Negative current collector 141: Part 1 142: Part 2 143: Bent section 150: Pad member 151: Evasion section 152: Opening 160: Insulating member 200: Battery module 210: Multiple battery cells 220: Housing 221: Housing body 225: Housing cover C: End

Claims

Claim 1 A battery cell comprising: an electrode assembly including a positive plate including a positive tab, a negative plate including a negative tab, and a separator; a cell case accommodating the electrode assembly; a cap plate assembly including a cap plate covering an open end of the cell case and an electrode terminal disposed on the cap plate; a current collector electrically connecting the electrode assembly and the electrode terminal; and a pad member coupled to the cap plate assembly; wherein the pad member includes an avoidance portion for avoiding at least a portion of the current collector. Claim 2 A battery cell according to claim 1, wherein the cap plate includes a vent portion, and the pad member includes an opening having a shape corresponding to the vent portion. Claim 3 A battery cell according to claim 1, wherein the current collector member includes a first portion coupled to the cap plate assembly, and the thickness of the pad member is 50% or more of the thickness of the first portion and 100% or less of the thickness of the first portion. Claim 4 In claim 1, the pad member is a battery cell comprising a synthetic rubber material. Claim 5 In claim 4, the synthetic rubber material comprises at least one of neoprene, butyl, and ethylene propylene diene monomer (EPDM), forming a battery cell. Claim 6 In claim 1, the pad member is a battery cell bonded to the cap plate using an adhesive. Claim 7 In claim 1, the pad member is a battery cell coupled to the cap plate while the current collector is coupled to the cap plate assembly. Claim 8 A battery cell according to any one of claims 1 to 7, wherein the current collector comprises a first portion coupled to the cap plate assembly and a second portion coupled to the positive tab or the negative tab, and the avoidance portion has a shape for avoiding the first portion. Claim 9 In any one of claims 1 to 7, the current collector is a battery cell comprising a bent portion having a bent shape. Claim 10 A battery cell according to any one of claims 1 to 7, wherein the positive electrode tab is disposed on one side of the first direction of the electrode assembly, the negative electrode tab is disposed on the other side of the first direction of the electrode assembly, and the electrode terminal is disposed on one side of the second direction of the electrode assembly, and the second direction is a direction perpendicular to the first direction. Claim 11 A battery cell according to any one of claims 1 to 7, wherein the current collector member comprises a first portion coupled to the cap plate assembly, the avoidance portion of the pad member has a shape corresponding to the first portion of the current collector member, and the pad member is coupled to at least a portion of the area of ​​the cap plate assembly where the current collector member is not coupled. Claim 12 A battery cell according to any one of claims 1 to 7, wherein the current collector comprises a positive current collector and a negative current collector, the positive current collector is arranged to cover at least a portion of one side in the first direction and one side in the second direction of the electrode assembly, and the negative current collector is arranged to cover at least a portion of the other side in the first direction and one side in the second direction of the electrode assembly. Claim 13 A battery cell according to any one of claims 1 to 7, wherein the positive electrode tab and the negative electrode tab are disposed opposite to the electrode terminal. Claim 14 A battery cell according to any one of claims 1 to 7, wherein the current collector comprises a second portion coupled to the positive tab or the negative tab, and the current collector is coupled to the positive tab or the negative tab while at least a portion of the second portion is covered by the positive tab or the negative tab. Claim 15 In any one of claims 1 to 7, the current collector is a battery cell joined to the positive tab or the negative tab through welding. Claim 16 A battery module comprising: a plurality of battery cells; and a module housing for accommodating the plurality of battery cells; wherein at least one of the plurality of battery cells comprises: an electrode assembly including a positive plate including a positive tab, a negative plate including a negative tab, and a separator; a cell case for accommodating the electrode assembly; a cap plate assembly including a cap plate covering an open end of the cell case and an electrode terminal disposed on the cap plate; a current collector electrically connecting the electrode assembly and the electrode terminal; and a pad member coupled to the cap plate assembly; wherein the pad member comprises an avoidance portion for avoiding at least a portion of the current collector.

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