Subassembly, and battery, battery pack, and vehicle including same

Abstract

A battery includes a battery housing, an electrode assembly housed in the battery housing, a terminal gasket positioned in a through-hole extending through an end wall of the battery housing, an electrode terminal positioned within the terminal gasket so as to be spaced from the end wall, and a deformable element positioned between the end wall and the electrode terminal to bias the electrode terminal towards the end wall. The battery housing has a first electrical polarity, and the electrode terminal has an opposite second electrical polarity. The biasing element may be a spring washer in a compressed state. The biasing element has a higher melting point than the terminal gasket. Accordingly, upon melting of the terminal gasket during thermal runaway, the deformable element returns towards an undeformed state to cause the electrode terminal to electrically contact the battery housing to induce a short circuit.

Description

Subassembly and batteries, battery packs, and automobiles including the same

[0001] The present invention relates to a battery subassembly and a battery, battery pack, and automobile including the same.

[0002] Reference to related applications

[0003] This application claims priority based on Korean Patent Application No. 10-2024-0138228, filed on October 11, 2024, the entire contents of which are incorporated herein by reference.

[0004]

[0005] Secondary batteries, which offer high applicability across product categories and possess electrical characteristics such as high energy density, are widely applied not only to portable devices but also to electric vehicles (EVs) and hybrid electric vehicles (HEVs) powered by electric driving sources.

[0006] These secondary batteries are attracting attention as a new energy source for improving eco-friendliness and energy efficiency because they drastically reduce the use of fossil fuels and have the advantage of not generating any by-products from energy use.

[0007] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. The operating voltage of these individual secondary batteries is generally about 2.5V to 4.5V. Therefore, if a higher output voltage is required, multiple batteries are connected in series to form a battery pack. Additionally, depending on the charge / discharge capacity required for the battery pack, multiple batteries are connected in parallel to form a battery pack. Accordingly, the number of batteries included in the battery pack and the electrical connection type can be set in various ways depending on the required output voltage and / or charge / discharge capacity.

[0008] Meanwhile, cylindrical, prismatic, and pouch-type batteries are known as types of secondary batteries. In the case of cylindrical batteries, an insulating separator is interposed between the positive and negative electrodes, and this is wound to form a jellyroll-shaped electrode assembly; this assembly is then inserted into a battery housing along with an electrolyte to constitute the battery. Additionally, strip-shaped electrode tabs may be connected to the uninsulated portions of the positive and negative electrodes, and these electrode tabs electrically connect the electrode assembly with the externally exposed electrode terminals. For reference, the positive electrode terminal is generally a cap of a seal that seals the opening of the battery housing, and the negative electrode terminal is generally the battery housing itself.

[0009] However, conventional cylindrical batteries having such a structure had the problem that current was concentrated in the strip-shaped electrode tabs connected to the positive electrode unoccupied part and / or the negative electrode unoccupied part, resulting in high resistance, excessive heat generation, and poor current collection efficiency.

[0010] Small cylindrical batteries with form factors such as 1865 (diameter: 16mm, height: 65mm) or 2170 (diameter: 21mm, height: 70mm) are generally considered not to cause increased resistance or heat generation problems. However, if the form factor is increased to apply cylindrical batteries to electric vehicles, a lot of heat can be generated around the electrode tabs during rapid charging, which can lead to a fire in the cylindrical battery.

[0011] To solve these problems, a cylindrical battery (so-called tab-less cylindrical battery) is proposed that has a structure with improved current collection efficiency by designing a positive electrode-free section and a negative electrode-free section to be located at the top and bottom, respectively, of a jellyroll-type electrode assembly, and welding a current collector to these non-free sections.

[0012] FIGS. 1 to 3 illustrate the manufacturing process of a tapless cylindrical battery. Specifically, FIG. 1 illustrates the structure of an electrode unfolded into a planar state, FIG. 2 illustrates the winding direction in which a laminate of electrodes and a separator is wound to form an electrode assembly, and FIG. 3 illustrates the state in which the wound electrode assembly is arranged to be welded to a current collector. FIG. 4 is a cross-sectional view of a finished tapless cylindrical battery cut along the longitudinal direction (Y).

[0013] Referring to FIGS. 1 to 4, the positive electrode (10) and the negative electrode (11) have a structure in which an active material (21) is coated on a sheet-shaped current collector (20), and a non-active portion (22) is formed along one long side of each electrode before being wound along the winding direction (X).

[0014] The electrode assembly (A) is manufactured by sequentially stacking the positive electrode (10) and the negative electrode (11) together with two separator membranes (12) as shown in FIG. 2, and then winding them around an axis extending in the Y direction so that the wound portion proceeds in the X direction as shown in FIG. 2. At this time, the unwound portions of the positive electrode (10) and the negative electrode (11) are arranged in opposite directions along the Y direction.

[0015] After the winding process, the unwound portion (10a) of the positive electrode (10) and the unwound portion (11a) of the negative electrode (11) are bent in the direction of the central core where the electrode assembly is wound, as shown in FIG. 3. After that, current collectors (30, 31) are welded to the bent unwound portions (10a, 11a), respectively, to join them.

[0016] The positive electrode unoccupied portion (10a) and the negative electrode unoccupied portion (11a) serve as electrode tabs, and the current collectors (30, 31) are each connected to external electrode terminals, thereby forming a current path with a large cross-sectional area within a cross-section perpendicular to the winding axis direction (Y-axis direction) of the electrode assembly (A), which can reduce the resistance of the battery. This is because resistance is inversely proportional to the cross-sectional area of ​​the path through which the current flows.

[0017] However, as the form factor of cylindrical batteries increases and the intensity of the charging current during rapid charging increases, overheating issues may recur.

[0018] A conventional tapless cylindrical battery (40) includes a battery housing (41) and a seal (42) as illustrated in FIG. 4. The battery housing (41) is referred to as a battery can. The seal (42) includes a cap (42a), a sealing gasket (42b), and a connecting plate (42c). The sealing gasket (42b) wraps around the edge of the cap (42a) and is secured by a crimping portion (43). Additionally, an electrode assembly (A) is secured within the battery housing (41) by a beading portion (44) to prevent vertical movement.

[0019] Typically, the positive terminal is the cap (42a) of the seal (42) and the negative terminal is the battery housing (41). Accordingly, the current collector (30) coupled to the non-positive portion (10a) of the positive electrode (10) is electrically connected to the connecting plate (42c) attached to the cap (42a) via a strip-shaped lead (45). Additionally, the current collector (31) coupled to the non-positive portion (11a) of the negative electrode (11) is electrically connected to the bottom portion of the battery housing (41). The insulator (46) covers the current collector (30) to prevent the battery housing (41) and the non-positive portion (10a) of the positive electrode (10), which have different polarities, from coming into contact with each other and causing a short circuit.

[0020] When the current collector (30) is connected to the connection plate (42c), a strip-shaped lead (45) is used. The lead (45) is either attached separately to the current collector (30) or manufactured integrally with the current collector (30). However, since the lead (45) is in the form of a thin strip, its cross-sectional area is small, so a large amount of heat is generated when a rapid charging current flows. In addition, the excessive heat generated from the lead (45) is transferred to the electrode assembly (A) side, causing the separator (12) to shrink, which can cause an internal short circuit, a major cause of thermal runaway.

[0021] The lead (45) also occupies a significant amount of installation space within the battery housing (41). Therefore, the cylindrical battery (40) containing the lead (45) has low space efficiency, which limits the increase in energy density.

[0022] Additionally, the upper part of the crimping portion (43) has negative polarity but has a small area. Although the crimping portion (43) is depicted as large in the drawing, in reality, the upper part of the crimping portion (43) has a very small area compared to the seal (42). Therefore, in order to stably connect the bus bar components, the positive electrode must be connected to the crimped seal (42) in the open end area of ​​the battery housing (41), and the negative electrode must be connected to the bottom part of the battery housing (41).

[0023] As such, in order to connect conventional tapless cylindrical batteries (40) in series and / or parallel, bus bar components must be connected to the cap (42a) of the seal (42) and the bottom surface of the battery housing (41), which reduces space efficiency. A battery pack installed in an electric vehicle contains hundreds of cylindrical batteries (40). Therefore, the inefficiency of electrical wiring can cause significant inconvenience not only during the assembly process of the electric vehicle but also during the maintenance of the battery pack.

[0024] Meanwhile, multiple lithium-ion batteries can be electrically connected and housed together inside a module case to form a single battery module. In this case, each lithium-ion battery contained within a single battery module can be referred to as a battery cell. Furthermore, multiple such battery modules can be connected to form a single battery pack. However, when a battery pack contains multiple battery modules and each module contains multiple battery cells, it may be vulnerable to thermal chain reactions between battery modules or between battery cells. For example, if a thermal runaway phenomenon occurs within a single battery module, such a phenomenon can propagate to other battery modules or other battery cells. Therefore, it is desirable to more effectively suppress the propagation of thermal runaway between battery modules or between battery cells.

[0025] The present invention was conceived against the background of the aforementioned prior art and aims to preferably improve space efficiency within the battery housing by improving the electrode terminal structure of a cylindrical battery, thereby reducing the internal resistance of the cylindrical battery and increasing energy density.

[0026] The present invention also aims to reduce or prevent internal heat generation that may occur during rapid charging by preferably increasing the cross-sectional area of ​​the current path within the battery.

[0027] The present invention can also help prevent the spread of fire to adjacent batteries by inducing contact between the battery housing and the electrode terminals when thermal runaway occurs.

[0028] The present invention also provides a structure that enables electrical wiring work for series and / or parallel connection of cylindrical batteries to be performed on one side of the battery.

[0029] The present invention also provides a battery pack manufactured using a cylindrical battery having an improved structure and a vehicle including the same.

[0030] Meanwhile, the technical problem that the present invention aims to solve is not limited to the problem described above, and also includes various other problems that can be clearly understood by those skilled in the art from the following description of the specification.

[0031]

[0032] According to one aspect of the present invention, a subassembly of a battery is provided.

[0033] According to one aspect of the present invention, a subassembly of a battery is provided, comprising: a battery housing that extends axially and has an open end region on a first side along the axial direction and a closed end region on a second side opposite, wherein the closed end region is formed by an end wall having a through hole; a terminal gasket disposed within the through hole; an electrode terminal disposed within the terminal gasket, spaced apart from the end wall of the battery housing by the terminal gasket, and exposed to the outside of the battery housing; and a shape-deforming member disposed between the end wall and the electrode terminal, which applies a force in the direction of the end wall to at least a portion of the electrode terminal.

[0034] According to another aspect of the present invention, the electrode terminal may comprise: a body portion disposed in the through hole; an outer flange portion extending radially outward from an outer end of the body portion; and an inner flange portion extending radially outward from an inner end of the body portion.

[0035] According to another aspect of the present invention, the body portion, the outer flange portion, and the inner flange portion may be integrally formed as an integrated structure.

[0036] According to another aspect of the present invention, the inner surface facing the interior of the inner flange portion may define a flat weld.

[0037] According to another aspect of the present invention, the terminal gasket may comprise: an outer gasket interposed between the outer flange portion and the outer surface of the end wall of the battery housing; an inner gasket interposed between the inner flange portion and the inner surface of the end wall of the battery housing; and an intermediate gasket extending between the body portion and the end wall of the battery housing to connect the outer gasket and the inner gasket.

[0038] According to another aspect of the present invention, the shape-deforming member may be interposed between the outer flange portion and the outer gasket.

[0039] According to another aspect of the present invention, the shape-deforming member may be interposed between the outer surface of the end wall of the battery housing and the outer gasket.

[0040] According to another aspect of the present invention, the shape deformation member may include an elastic bias member or a temperature-responsive deformation member.

[0041] According to another aspect of the present invention, the elastic bias member comprises an elastic bias member, and the elastic bias member may be a spring washer.

[0042] According to another aspect of the present invention, the battery housing may have a cylindrical shape.

[0043] According to another aspect of the present invention, the shape-deforming member comprises an elastic bias member, and the elastic bias member may be positioned in a compressed state biased to expand into a shape that is not deformed by a predetermined amount of displacement along the axial direction.

[0044] According to another aspect of the present invention, the shape-deforming member may be positioned in a biased state so as to expand into a shape that is not deformed by a predetermined amount of displacement along the axial direction.

[0045] According to another aspect of the present invention, the displacement amount may be greater than or equal to the thickness of the terminal gasket.

[0046] According to another aspect of the present invention, the displacement amount may be greater than or equal to the total thickness of all parts of the terminal gasket along the axial direction.

[0047] According to another aspect of the present invention, the shape-deforming member may be conductive.

[0048] According to another aspect of the present invention, the melting point of the shape-deforming member may be higher than the melting point of the terminal gasket.

[0049] According to another aspect of the present invention, a battery is provided, comprising: a subassembly according to the aforementioned aspect; and an electrode assembly that is accommodated within the internal space of the battery housing, wherein a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode are wound together, and wherein the first electrode is electrically connected to the battery housing and the second electrode is electrically connected to an electrode terminal.

[0050] According to another aspect of the present invention, the battery housing may further include a sealing member located on and sealing the open end region of the battery housing.

[0051] According to another aspect of the present invention, the battery housing may further include a crimping portion extending inwardly in radius to surround the edge of the seal.

[0052] According to another aspect of the present invention, a battery pack comprising a battery according to the aforementioned aspect is provided.

[0053] According to another aspect of the present invention, an automobile comprising a battery pack according to the aforementioned aspect is provided.

[0054]

[0055] According to one aspect of the present invention, the internal resistance of a battery can be lowered and energy density increased by improving the electrode terminal structure of the battery to increase space efficiency within the battery housing.

[0056] According to another aspect of the present invention, the spread of fire to adjacent batteries can be prevented by inducing contact between the battery housing and the electrode terminals when a thermal runaway phenomenon occurs. Such contact can be induced by using a shape-deforming member in the electrode terminal structure.

[0057] According to another aspect of the present invention, the problem of internal heat generation during rapid charging can be improved by improving the electrode terminal structure of the battery to expand the cross-sectional area of ​​the current path.

[0058] According to another aspect of the present invention, electrical wiring work for series and / or parallel connection of batteries can be performed on one side of the batteries.

[0059] According to another aspect of the present invention, a battery pack manufactured using a battery having an improved structure and a vehicle including the same can be provided.

[0060] The desirable effects mentioned above are merely limiting examples of the present invention, and the present invention may provide various other advantages not explicitly mentioned herein.

[0061]

[0062] The following drawings attached to this specification illustrate preferred aspects of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the aforementioned description; therefore, the present invention should not be interpreted as being limited to the embodiments illustrated in the drawings.

[0063] Figure 1 is a plan view showing the structure of an unfolded electrode used in a conventional tap-less cylindrical battery.

[0064] Figure 2 is a side view of a conventional tabless cylindrical battery before the electrode and separator laminate is wound.

[0065] Figure 3 is a diagram showing the state in which the electrode assembly of Figure 2 is arranged to be welded to the current collector.

[0066] FIG. 4 is a cross-sectional view of a conventional tap-less cylindrical battery cut along the axial direction (Y).

[0067] FIG. 5 is a cross-sectional view of the end of a cylindrical battery showing a subassembly of a battery according to one aspect of the present invention.

[0068] Figure 6a is an enlarged cross-sectional view of the part enclosed by the dotted circle in Figure 5.

[0069] FIG. 6b is an enlarged cross-sectional view of a subassembly of a battery according to another embodiment of the present invention.

[0070] FIG. 6c is a perspective view showing an elastic bias member disposed between a terminal gasket and an electrode terminal according to one aspect of the present invention.

[0071] FIG. 6d is a side view of the elastic bias member of FIG. 6c in an undeformed state.

[0072] FIG. 6e is a perspective view showing a first shape and a second shape of a temperature-responsive deformable member according to another aspect of the present invention.

[0073] FIG. 6f is a cross-sectional view schematically showing a shape-deformed member applying force in the direction of the end wall to at least a portion of the electrode terminal.

[0074] FIG. 7a is a cross-sectional view of a cylindrical battery according to one aspect of the present invention, cut along the axial direction (Y).

[0075] FIG. 7b is a cross-sectional view of a cylindrical battery according to another embodiment of the present invention, cut along the axial direction (Y).

[0076] FIG. 8 is a plan view showing an unfolded electrode structure according to one aspect of the present invention.

[0077] FIG. 9 is a cross-sectional view taken along the axial direction (Y) of an electrode assembly according to one aspect of the present invention, and includes a winding structure with a non-removable portion applied.

[0078] FIG. 10a is a cross-sectional view according to one aspect of the present invention showing a state in which the unwound portion of the electrode assembly of FIG. 9 is bent in the direction of the winding axis.

[0079] FIG. 10b is a perspective view of the electrode assembly shown in FIG. 10a.

[0080] FIG. 11 is a partially cut-off perspective view of a battery pack including cylindrical batteries according to one aspect of the present invention.

[0081] FIG. 12 is a schematic diagram of a vehicle including a battery pack according to one aspect of the present invention.

[0082] Hereinafter, one aspect of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and the appended claims should not be interpreted as being limited to their general or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the present invention. This is in accordance with the principle that the inventor has the right to define terms in order to describe their invention in the most appropriate manner.

[0083] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely preferred examples for explaining the technical concept of the present invention and are not intended to limit the present invention. Accordingly, it should be understood that various equivalents and modifications are possible within the scope of the present invention at the time of filing.

[0084] Additionally, to aid in understanding the invention, the attached drawings are not drawn to actual scale, and the dimensions of some components may be exaggerated. Furthermore, the same reference numerals may be assigned to identical or corresponding components across different embodiments.

[0085] Although terms such as "first," "second," etc., are used to describe various components, these components are not limited by such terms. These terms are used merely for convenience to distinguish one component from another, and unless specifically stated otherwise, the first component may be the second component, and vice versa.

[0086] Throughout the specification, unless specifically stated otherwise, each component may be singular or plural.

[0087] The fact that any configuration is placed on the "top" or "top" of a component may mean not only that the configuration is placed in contact with the top surface of the component, but also that another configuration may be interposed between the component and the configuration placed on the component.

[0088] In addition, where it is stated that a component is "connected," "combined," or "joined" to another component, this means that the component may be directly connected to the other component or indirectly connected through one or more components.

[0089] Throughout the specification, "A and / or B" means A, B, or A and B unless specifically stated otherwise, and "C to D" means C or more and D or less unless specifically stated otherwise.

[0090] For convenience of explanation, in this specification, the direction following the longitudinal direction of the winding axis of the electrode assembly wound in a jelly roll shape is referred to as the axial direction (Y). Additionally, the direction surrounding the winding axis and extending along the longitudinal direction of the wound electrode and separator is referred to as the circumferential direction or periphery direction (X). Furthermore, the direction facing the winding axis or moving away from the winding axis is referred to as the radial direction; specifically, the direction facing the winding axis is referred to as the centripetal direction, and the direction moving away from the winding axis is referred to as the centrifugal direction.

[0091] Throughout the specification, "subassembly of battery" (or "subassembly") refers to a part of the battery assembly and may refer to a fixing structure of the electrode terminals.

[0092]

[0093] A cylindrical battery according to one aspect of the present invention may include an electrode terminal disposed within a through hole formed in the end wall of a battery housing. The electrode terminal is spaced apart from the end wall of the battery housing by the terminal gasket and is exposed to the outside of the battery housing.

[0094] FIG. 5 is a cross-sectional view showing a fixing structure of a subassembly of a battery, for example, an electrode terminal (50), according to one aspect of the present invention, and FIG. 6a is an enlarged view of the area enclosed by the dotted circle of FIG. 5.

[0095] Referring to FIGS. 5 and 6a, the electrode terminal (50) may include a body portion (50a) comprising an upper surface, a lower surface, and an outer surface, and an outer flange portion (50b) that protrudes radially outward from the outer surface of the body portion (50a) and extends along the outer surface (52a) of the end wall (52) of the battery housing (51). Additionally, it may include an inner flange portion (50c) that protrudes from the outer surface of the body portion (50a) and is formed such that at least a portion faces the inner surface (52b) of the end wall (52) of the battery housing (51). The upper surface of the body portion (50a) is flat and may be connected to a current collector and may be positioned along the axial direction (Y) away from the end wall (52) of the battery housing (51), i.e., at a higher position than the inner flange portion (50c).

[0096] A fixing structure for an electrode terminal (50) according to one aspect of the present invention may be applied to a cylindrical battery housing (51) having a structure with one side open, and may be a structure in which the electrode terminal (50) is fixed by being extended through a through hole (53) formed in an end wall (52) corresponding to the opposite side of the open side. Specifically, the fixing structure for the electrode terminal (50) may include a terminal gasket (54) interposed between the electrode terminal (50) and the through hole (53).

[0097] The battery housing (51) may include a side wall that is connected to the radially outer portion of the end wall (52) and extends therefrom to define the cylindrical shape of the battery housing. Additionally, the battery housing (51) may be formed in other shapes, such as a rectangular structure having a square or other polygonal cross-section in a plane perpendicular to the axial direction (Y).

[0098] The battery housing (51) may be made of a conductive metal material. In one example, the battery housing (51) may be made of steel, but the present invention is not limited thereto. The inner and outer surfaces of the battery housing (51) may be coated with a plating layer such as a Ni plating layer.

[0099] The electrode terminal (50) may also be made of a conductive metal material. In one example, the electrode terminal (50) may be made of aluminum, but the present invention is not limited thereto. The electrode terminal (50) may be made of a 10-series aluminum alloy that is easy to plastically process and has low electrical resistance. Plastic processing refers to a technique of applying physical force to a metal to deform it into a desired shape, and may include riveting, caulking, fullering, etc.

[0100] The terminal gasket (54) may be made of a polymer resin having electrical insulation and elasticity. In one example, the terminal gasket (54) may be made of polypropylene, polybutylene terephthalate, polyfluoroethylene, etc., but the present invention is not limited thereto.

[0101] Preferably, the electrode terminal (50) is installed through the through hole (53) so as not to come into contact with the inner wall of the through hole (53). The electrode terminal (50) is installed with the body portion (50a) inserted into the through hole (53), and the body portion (50a) extends through the through hole (53).

[0102] The outer flange portion (50b) extends from the perimeter of the first end portion of the body portion (50a) exposed to the outside through the end wall (52) of the battery housing (51) and extends along the outer surface (52a) of the end wall (52).

[0103] The inner flange portion (50c) may be formed to extend from the second end portion of the body portion (50a) protruding inward through the end wall (52) of the battery housing (51), so that at least a portion faces the inner surface (52b) of the end wall (52).

[0104] The electrode terminal (50) may include a flat portion (50d) on the inner side of the inner flange portion (50c). The flat portion (50d) is an example of a welded portion, and a welded portion refers to a part that is welded to another member. The flat portion (50d) may be circumferentially surrounded by the inner flange portion (50c).

[0105] The flat portion (50d) corresponds to the upper surface of the second end portion of the body portion (50a) and may include a surface that is at least partially flat. Additionally, at least a portion of the flat portion (50d) may be parallel to the inner surface (52b) of the end wall (52) of the battery housing (51). Here, "parallel" means a state that is substantially parallel when observed with the naked eye. The flat portion (50d) may be a surface that is already formed before the electrode terminal (50) is plastically processed within the through hole (53). That is, the flat portion (50d) may be an area of ​​the electrode terminal (50) that is not deformed by plastic processing.

[0106] Preferably, the inner flange portion (50c) may be formed by plastically processing the upper perimeter area of ​​the body portion (50a) with a material such as metal. The plastic processing may be caulking. However, the present invention is not limited thereto. In one aspect, the electrode terminal (50) may be a rivet terminal riveted through the through hole (53) by the inner flange portion (50c). That is, the electrode terminal (50) may be an integral member that is deformed by riveting from a preform shape to a final shape while positioned in the through hole (53).

[0107] The inner flange portion (50c) may extend outward from the electrode terminal body portion (50a) and away from the end wall (52) of the battery housing (51). At this time, the angle (θ) between the surface of the inner flange portion (50c) facing the end wall (52) of the battery housing (51) and the inner surface (52b) of the bottom portion of the battery housing (51) may be, for example, in the range of 0 to 60 degrees. The angle (θ) is determined by the caulking strength when the electrode terminal (50) is fixed by caulking within the through hole (53) of the battery housing (51). For example, as the caulking strength increases, the angle (θ) may approach 0 degrees. On the other hand, if the angle (θ) exceeds 60 degrees, the sealing effect of the terminal gasket (54) may be reduced.

[0108] Since the outer flange portion (50b) is substantially parallel to the end wall (52) of the battery housing (51), the angle formed between the inner flange portion (50c) and the outer flange portion (50b) may also be in the range of 0 to 60 degrees, just like the angle (θ).

[0109] According to another aspect, a recess (55) may be formed between the inner flange portion (50c) and the flat portion (50d). The recess (55) may be in the form of a groove recessed in the body portion (50a) along the axial direction (Y). The groove may have a closed loop, an annular, or toroidal shape with respect to the central axis of the body portion (50a). The cross-section of the recess (55) may be symmetrical or asymmetrical and rotated with respect to the central axis to form an annular or toroidal shape. In one example, the cross-section may be approximately V-shaped or U-shaped. Examples of an asymmetric cross-section may include a side wall (55a) extending perpendicularly to the flat portion (50d) and an inclined surface (55b) connected to the end of the side wall (55a) to form part of the upper surface of the inner flange portion (50c). The outer surface of the side wall (55a) may be the first surface of the recess (55), and the inclined surface (55b) may be the second surface. As illustrated in FIGS. 6a and 6b, the first surface and the second surface may be asymmetric to each other. For example, as in FIG. 6a, the side wall (55a) may be substantially perpendicular to the inner surface (52b) of the end wall (52) of the battery housing (51) or substantially parallel to the central axis of the body portion (50a). Here, 'perpendicular' means a state that is substantially perpendicular when observed with the naked eye. In another example, as illustrated in FIG. 6b, the side wall (55a) may be formed to be inclined toward the flat portion (50d). The recess (55) can be formed by the shape of a caulking jig used when the electrode terminal (50) is fixed to the through hole (53) of the battery housing (51) by a caulking method.

[0110] According to one aspect, the thickness of the inner flange portion (50c) may gradually decrease as it moves away from the body portion (50a) of the electrode terminal (50).

[0111] According to another aspect, the terminal gasket (54) may include an outer gasket (54b) interposed between the outer flange portion (50b) and a first plane (P1) where the outer surface (52a) of the end wall (52) of the battery housing (51) is located, an inner gasket (54a) interposed between the inner flange portion (50c) and a second plane (P2) where the inner surface (52b) of the end wall (52) of the battery housing (51) is located, and an intermediate gasket (54c) interposed between the body portion (50a) and the through hole (53) and connecting the outer gasket (54b) and the inner gasket (54a).

[0112] The thickness of the outer gasket (54b) and / or the inner gasket (54a) and / or the intermediate gasket (54c) may vary depending on the location. For example, the terminal gasket (54) may have a minimum thickness in the intermediate gasket (54c) area. In one aspect, the thickness of the area adjacent to the first plane (P1) of the intermediate gasket (54c) may increase as it approaches the first plane (P1).

[0113] Similarly, the area adjacent to the second plane (P2) of the intermediate gasket (54c) may also have an increased thickness as it approaches the second plane (P2). Additionally, the central area of ​​the intermediate gasket (54c) located between the first plane (P1) and the second plane (P2) may have a uniform thickness.

[0114] Preferably, the end wall (52) of the battery housing (51) may be thinner in the area adjacent to the radial inner edge (56) of the through hole (53). Additionally, a minimum thickness point may exist in the area of ​​the intermediate gasket (54c) located between the inner edge (56) of the through hole (53) and the inner flange portion (50c). Furthermore, the inner edge (56) of the through hole (53) may include a counter-face (57) facing the inner flange portion (50c).

[0115] Meanwhile, the upper and lower ends of the inner wall of the through hole (53), which is perpendicular to the end wall (52) of the battery housing (51), may be corner-cut to form a tapered surface toward the electrode terminal (50). However, the upper and / or lower ends of the inner wall of the through hole (53) may alternatively be deformed into a smooth curved surface with curvature. In this case, the stress applied to the gasket (54) near the upper and / or lower ends of the inner wall of the through hole (53) can be further relieved.

[0116] Preferably, the inner gasket (54a) may extend longer than the inner flange portion (50c) and form an angle (θ) in the range of 0° to 60° with the inner surface (52b) of the end wall (52) of the battery housing (51).

[0117] In another aspect, the diameter of the flat portion (50d) of the electrode terminal (50) may be determined based on the welding strength between the current collector and the flat portion (50d). The weld tensile strength between the flat portion (50d) and the current collector may be at least 2 kgf, or 5 kgf, or 6 kgf, or 7 kgf, or 8 kgf, or 9 kgf, or 10 kgf. It is desirable to increase the weld tensile strength as much as possible within an allowable range by selecting the best welding method.

[0118] In another aspect, as illustrated in FIG. 5, the radius (R1) from the center of the body portion (50a) to the edge of the outer flange portion (50b) may be 10 to 70% of the radius (R2) of the end wall (52) of the battery housing (51).

[0119] If R1 becomes smaller, there may be insufficient welding space when welding components (e.g., busbars) used for electrical connection of the electrode terminal (50). Additionally, if R1 becomes larger, the welding space may be reduced when welding components for electrical connection to the outer surface (52a) of the end wall (52) of the battery housing (51) outside the electrode terminal (50).

[0120] Therefore, if the ratio R1 / R2 is adjusted to a range of 10 to 70%, a welding space can be adequately secured for both the electrode terminal (50) and the outer surface (52a) of the end wall (52) of the battery housing (51).

[0121] Additionally, the radius (R3) from the center of the body portion (50a) of the electrode terminal (50) to the edge of the flat portion (50d) may be 4% to 30% based on the radius (R2) of the end wall (52) of the battery housing (51).

[0122] If R3 becomes smaller, there may be insufficient welding space when welding the current collector to the flat portion (50d) of the electrode terminal (50), and the welding area of ​​the electrode terminal (50) may decrease, which may increase contact resistance. Additionally, R3 must be smaller than R1, and if R3 becomes larger, the thickness of the inner flange portion (50c) becomes thinner, and the force with which the inner flange portion (50c) compresses the terminal gasket (54) becomes weaker, which may further reduce the sealing ability of the terminal gasket (54).

[0123] However, if R3 / R2 is adjusted to a range of 4 to 30%, the contact resistance of the welding area can be reduced by sufficiently securing the welding area of ​​the flat portion (50d) of the electrode terminal (50) and the current collector, and the sealing performance of the terminal gasket (54) can also be properly maintained.

[0124] According to one aspect of the present invention, a fixing structure of an electrode terminal (50) can be formed using a corking jig that moves up and down. First, a preform (not shown) of the electrode terminal (50) can be inserted into an end wall (52) in a manner similar to a rivet. Here, the preform refers to the electrode terminal before the corking process is performed. Initially, a terminal gasket (54) can be placed within a through hole (53) formed in the end wall (52) of the battery housing (51).

[0125] Subsequently, a corking jig is inserted into the internal space of the battery housing (51). The corking jig includes a groove and a protrusion corresponding to the final shape of the electrode terminal (50), thereby forming the electrode terminal (50) by pressurizing the preform. That is, the surface of the corking jig facing the preform may include a groove to accommodate the flat portion (50d) of the electrode terminal, and the annular protrusion surrounding the groove may be shaped to contribute to forming the internal flange portion (50c) and / or recess portion (55) through plastic deformation during the process of pressurizing the preform.

[0126] Next, the corking jig descends and presses the upper part of the preform, thereby transforming the preform into an electrode terminal (50) that is riveted into the through hole (53) of the battery housing (51). The insertion depth of the corking jig can be regulated by the flat section (50d), which is a structure that was previously formed in the body section (50a). The corking jig includes a groove into which the flat section (50d) is inserted, and while the preform is being pressurized, the pressurization is stopped when the flat section (50d) comes into contact with the bottom of the groove. Accordingly, the internal flange section (50c) and the recess section (55) formed through plastic deformation can maintain a uniform shape even during mass production. Additionally, since the flat section (50d) is not deformed or its deformation is minimized during pressurized forming, the flat section (50d) can also maintain a stable shape during the mass production process. As a result, welding between the flat section (50d) and the current collector in the subsequent process becomes easier, and deviations that may occur during the manufacturing process can also be effectively reduced.

[0127] While the shape of the preform is deformed as it is pressed by the corking jig, the outer gasket (54b) interposed between the outer flange portion (50b) and the outer surface (52a) of the end wall (52) of the battery housing (51) is elastically compressed, and its thickness is reduced. Additionally, a portion of the intermediate gasket (54c) interposed between the inner edge (56) of the through hole (53) and the preform is elastically compressed by the inner flange portion (50c), and its thickness is reduced even more than in other areas. In particular, the area where the thickness of the intermediate gasket (54c) is intensively reduced is the part indicated by the dotted circle in FIG. 6A. Accordingly, the sealing and airtightness between the riveted electrode terminal (50) and the battery housing (51) are significantly improved.

[0128] Preferably, the terminal gasket (54) is sufficiently compressed so that the desired sealing strength is secured without the preform being physically damaged during the riveting process through a sintering process called corking.

[0129] Preferably, the compression ratio of the terminal gasket (54) may be 30% to 90%. The minimum compression ratio corresponds to the minimum level of compression ratio required to ensure the sealing (sealability) of the electrode terminal (50). The maximum compression ratio corresponds to the maximum level of compression ratio that can be achieved without physically damaging the terminal gasket (54).

[0130] According to one aspect of the present invention, when the terminal gasket (54) is made of polybutylene terephthalate, it is preferable that the terminal gasket (54) has a compression ratio of 50% or more at the point where it is compressed to a minimum thickness (e.g., areas indicated by dotted circles in FIG. 6a).

[0131] According to one aspect of the present invention, the compression ratio may be defined as the ratio of the change in thickness at the maximum compression point to the thickness of the terminal gasket (54) before compression. The thickness of the inner gasket (54a) and the intermediate gasket (54c) before compression may be uniform, and the maximum compression point may be located near the inner edge (56) portion of the through hole (53). Additionally, it is preferable to calculate the compression ratio based on the uniform thickness of the inner gasket (54a) and the intermediate gasket (54c).

[0132] According to another aspect of the present invention, when the terminal gasket (54) is made of polyfluoroethylene, it is preferable that the terminal gasket (54) has a compression ratio of 60% or more at the point where it is compressed to a minimum thickness. Additionally, it is preferable to calculate the compression ratio based on the uniform thickness of the inner gasket (54a) and the intermediate gasket (54c).

[0133] According to another aspect of the present invention, when the terminal gasket (54) is made of polypropylene, it is preferable that the terminal gasket (54) has a compression ratio of 60% or more at the point where it is compressed to a minimum thickness. Additionally, the compression ratio may be calculated based on the uniform thickness of the inner gasket (54a) and the intermediate gasket (54c).

[0134] Preferably, the process of pressurizing the upper part of the preform can be performed in stages by moving the corking jig up and down two or more times. That is, the preform can be gradually deformed through the repeated up-and-down movement of the corking jig, and the pressure applied to the corking jig can be gradually increased at each stage. By doing so, the stress applied to the preform is distributed over time, thereby preventing damage to the terminal gasket (54) during the corking process. In particular, damage to the gasket can be minimized even when the intermediate gasket (54c) located between the inner edge (56) of the through hole (53) and the preform is strongly compressed by the inner flange portion (50c).

[0135] After the pressure forming of the preform using the corking jig is completed, the corking jig is separated from the battery housing (51), and a fixing structure of the electrode terminal (50) according to the side of the present invention can be obtained as shown in FIG. 6a.

[0136] Meanwhile, the structure of the electrode terminal (50) can have various shapes depending on the design of the preform and / or corking jig and / or terminal gasket (54) as well as the magnitude of the pressure applied to the preform during the corking process.

[0137] FIG. 6b is an enlarged cross-sectional view illustrating the structure of an electrode terminal (50') according to another aspect of the present invention.

[0138] Referring to FIG. 6b, the electrode terminal (50') according to the other side has a riveted structure such that the inner flange portion (50c) extends at least a portion toward the inner surface (52b) of the end wall (52) of the battery housing (51). That is, the inner flange portion (50c) includes a first region (50c1) that extends in a direction spaced at least a portion away from the end wall (52) of the battery housing (51), and a second region (50c2) that is connected to the first region (50c1) and extends again toward the end wall (52) of the battery housing (51).

[0139] The angle (δ) between the surface of the second section (50c2) facing the end wall (52) of the battery housing (51) and the inner surface (52b) of the end wall (52) may be in the range of 0° to 30°. Preferably, the angle (δ) is set to be close to 0° to maximize the sealing performance of the terminal gasket (54). That is, the second section (50c2) strongly compresses the inner gasket (54a) to improve the sealing performance of the terminal gasket (54), and this effect becomes greater as the angle (δ) approaches 0°.

[0140] The terminal gasket (54) may include an outer gasket (54b) interposed between the outer flange portion (50b) and the first plane (P1) where the outer surface (52a) of the end wall (52) of the battery housing (51) is located; an inner gasket (54a) interposed between the inner flange portion (50c) and the second plane (P2) where the inner surface (52b) of the end wall (52) of the battery housing (51) is located; and an intermediate gasket (54c) interposed between the body portion (50a) and the through hole (53) and connecting the outer gasket (54b) and the inner gasket (54a).

[0141] Preferably, the thickness of the intermediate gasket (54c) may gradually decrease as it moves away from the outer gasket (54b). Additionally, the inner gasket (54a) may decrease to a minimum thickness near the radially outer end of the inner flange portion (50c), and then slightly increase in thickness toward the radially inner end. This compressed structure of the inner gasket (54a) can further improve the sealing performance of the electrode terminal (50′). The compression ratio of the inner gasket (54a) can be calculated at the minimum thickness point located near the end of the inner flange portion (50c).

[0142] In one aspect of the present invention, a shape-deforming member (58) may be provided between the end wall (52) of the battery housing (51) and the electrode terminal (50). In one aspect of the present invention, the shape-deforming member (58) may be interposed between the outer flange portion (50b) and the outer gasket (54b). In another aspect of the present invention, the shape-deforming member (58) may be interposed between the outer surface of the end wall (52) of the battery housing (51) and the outer gasket (54b).

[0143] In one aspect of the present invention, the shape deformation member (58) may include an elastic bias member (581) or a temperature-responsive deformation member (582).

[0144] FIGS. 6c and 6d illustrate an elastic bias member (581) according to one aspect of the present invention. The elastic bias member (581) has no limitations in shape when applying force in the direction of the end wall (52) to at least a portion of the electrode terminal (50). For example, the elastic bias member (581) may take various forms as described below, but may take the form of a spring washer. Below, the operation of the elastic bias member (581) of the present invention is described based on the form of a spring washer.

[0145] In one aspect of the present invention, the elastic bias member (581) may be an annular spiral structure having a height difference (d) with the starting point and the end point offset in a vertical direction in a non-deformed state. The elastic bias member (581) may be formed such that one end (581a) and the other end (581b) are spaced apart from each other, and may form a spiral or helical shape by rotating along a certain angle and inclination from the one end (581a) to the other end (581b). Such a spring washer may be a type of washer generally called a "split lock" washer.

[0146] According to one aspect of the present invention, the elastic bias member (581) may be positioned substantially parallel to the outer flange portion (50b), the outer gasket (54b), or the outer surface (52a) of the end wall (52) of the battery housing (51). Here, "substantially parallel" means that they are in a parallel relationship when observed visually. Additionally, the outer gasket (54b) may refer to an outer gasket in a non-deformed state.

[0147] According to one aspect of the present invention, an elastic bias member (581) may be placed in close contact between a terminal gasket (54) and an electrode terminal (50) so that no gap exists between them. Due to this close contact, the sealing performance of the terminal gasket (54) may be improved or maintained at a high level.

[0148] Specifically, the elastic bias member (581) can be mechanically fixed between the terminal gasket (54) and the electrode terminal (50) by compression of the terminal gasket (54). In other words, while the preform is deformed by being pressed by the corking jig, the elastic bias member (581) can be mechanically fixed between the terminal gasket (54) and the electrode terminal (50). As a result of this fixation, the elastic bias member (581) is compressed in the vertical direction so that there is no longer a substantial height difference between one end (581a) and the other end (581b).

[0149] According to one aspect of the present invention, the elastic bias member (581) may be deformed in shape when the preform is pressed after being placed between the terminal gasket (54) and the preform. Specifically, the elastic bias member (581) may be elastically deformed as the height difference between the ends (581a, 581b) decreases.

[0150] According to one aspect of the present invention, spring-type washers of various shapes may be used as elastic bias members (581). For example, any structure that is positioned between the outer flange portion (50b) of the electrode terminal (50) and the outer surface (52a) of the end wall (52) of the battery housing (51) and biased toward the through hole (53) in which the electrode terminal (50) is positioned to induce contact between the electrode terminal and the battery housing material may be used. Preferably, such a structure may be an annular structure surrounding the body portion (50a) of the electrode terminal (50). For example, various structures such as commonly used Belleville washers, wave springs, split wave springs, stacked wave springs, finger disc spring washers, and curved disc spring washers may be used. Alternatively, an annular disc structure made of compressible materials such as rubber or porous foam can also be used.

[0151] In any of the spring-type bias structures mentioned above, the structure should be capable of biasing so that it is restored to a non-deformed state when the terminal gasket (54) melts, and preferably, the shape and size should be set such that the degree of restoration is greater than the thickness of the outer gasket (54b), more preferably greater than the total thickness of the outer gasket (54b) and the inner gasket (54a).

[0152] FIG. 6e illustrates a temperature-responsive deformable member (582) according to another aspect of the present invention. The temperature-responsive deformable member (582) has no limitations in shape when applying force in the direction of the end wall (52) to at least a portion of the electrode terminal (50) at a high temperature. For example, the temperature-responsive deformable member (582) may be of various shapes and materials as described below, but as a type thereof, it may be in the form of a spring washer.

[0153] In another aspect of the present invention, the temperature-responsive deformable member (582) may be an annular spiral structure having a height difference (d) that is offset in the vertical direction of the start and end points in the first shape. The temperature-responsive deformable member (582) may be formed such that one end (582a) and the other end (582b) are spaced apart from each other, and may form a spiral or helical shape by rotating along a certain angle and inclination from the one end (582a) to the other end (582b).

[0154] In another aspect of the present invention, the temperature-responsive deformable member (582) exists in a second shape at the normal operating temperature of the battery, and can change into an annular spiral structure of the first shape at a temperature higher than the melting point of the terminal gasket (54).

[0155] In another aspect of the present invention, the temperature-responsive deformable member (582) may exist in a shape substantially parallel to the outer surface (52a) of the end wall (52) of the battery housing (51) in a second state. That is, it may exist in a shape as shown below in FIG. 6e. In this case, the temperature-responsive deformable member (582) may be placed in close contact between the terminal gasket (54) and the electrode terminal (50) so that there is no gap between them. Due to this close contact, the sealing performance of the terminal gasket (54) may be improved or maintained at a high level.

[0156] Additionally, the temperature-responsive deformation member (582) may be further mechanically fixed between the terminal gasket (54) and the electrode terminal (50) by compression of the terminal gasket (54), similar to the elastic bias member (581).

[0157] In another aspect of the present invention, the temperature-responsive deformable member (582) can change its shape from a second shape to a first shape in response to temperature in abnormal high-level situations of the battery, such as thermal runaway. Accordingly, the height difference between the ends (582a, 582b) may occur again.

[0158] In another aspect of the present invention, the temperature-responsive deformable member (582) may be made of various materials. For example, the temperature-responsive deformable member (582) may include, for example, a shape memory alloy, a bimetal comprising a stacked structure of metal materials having different coefficients of thermal expansion, a metal or alloy material that changes shape at high temperatures, a ring / semi-ring structure that restores to a wavy shape at high temperatures, a metal material having a flat shape at room temperature and a shape restoration function to return to a preset structure when the temperature rises, or a structure that is given the possibility of deformation by including protrusions or irregularities on its surface.

[0159] In another aspect of the present invention, the shape memory alloy may return to a remembered shape by a change in crystal structure at a specific temperature, for example, the temperature of a thermal runaway state. In another aspect of the present invention, the bimetal may comprise a laminated structure of a metal material that undergoes bending / twisting depending on the temperature. In another aspect of the present invention, the structure that is restored to a wavy shape at high temperatures may be a thermally expandable, deformable metal structure in which the structure bends due to thermal stimulation.

[0160] In any of the aforementioned temperature-responsive deformable members (582), if the terminal gasket (54) melts in a situation of abnormal behavior such as thermal runaway, it should be restored to a first shape so that biasing can be applied. At this time, it is preferable that the shape and size be set such that the degree of restoration is greater than the thickness of the outer gasket (54b), and more preferably greater than the total thickness of the outer gasket (54b) and the inner gasket (54a).

[0161] According to one aspect of the present invention, when at least a portion of the terminal gasket (54) is melted, the shape-deforming member (58) can be restored to a spiral structure having a height difference (d) between the ends (58a, 58b) in an undeformed state, thereby pushing the electrode terminal (50) outward so that the electrode terminal (50) and the battery housing (51) come into contact with each other.

[0162] FIG. 6f illustrates the state in which the formed deformation member (58) is restored to an undeformed spiral structure.

[0163] When the shape-deforming member (58) is fixed between the terminal gasket (54) and the electrode terminal (50) as shown in the upper figure of FIG. 6f, the shape-deforming member (58) is compressed to the extent that there is no substantial height difference between its one end (58a) and the other end (58b). Meanwhile, when heat is generated in the battery due to thermal runaway, the terminal gasket (54) melts because its melting point is lower than that of the shape-deforming member (58). Consequently, as shown in the lower figure of FIG. 6f, the shape-deforming member (58) can be restored to a non-deforming state that re-establishes a height difference d between its one end (58a) and the other end (58b). As a result, the shape-deforming member (58) acts like a lever to push the electrode terminal (50) outward, causing the electrode terminal (50) and the battery housing (51) to come into contact, thereby inducing a short circuit.

[0164] When the electrode terminal (50) and the battery housing (51) come into contact in this manner, the battery housing (51) connected to the first electrode and the electrode terminal (50) connected to the second electrode come into contact, and as a result, a large current can flow between the battery housing (51) and the electrode terminal (50). As a result, the current collector plate inside the battery or the bus bar included in the battery pack containing the battery may melt, and as a result, the cycling of the battery is stopped, thereby preventing thermal runaway.

[0165] According to another aspect of the present invention (not shown), the shape-deforming member (58) may be positioned at a different location to bias the electrode terminal (50) to contact the end wall (52) of the battery housing (51) when at least a portion of the terminal gasket (54) melts. For example, the shape-deforming member (58) may be positioned between the outer gasket (54b) and the outer surface (52a) of the end wall (52) of the battery housing (51) to push the electrode terminal (50) outward and induce a short circuit when the terminal gasket (54) melts. In another aspect, the shape-deforming member (58) may be positioned on the opposite side of the end wall (52) of the battery housing (51). That is, the shape-deforming member (58) may be located between the inner surface (52b) of the end wall (52) of the battery housing (51) and the inner gasket (54a), or between the inner gasket (54a) and the inner flange portion (50c) of the electrode terminal (50). In either of these locations, melting of the terminal gasket (54) may cause the shape-deforming member (58) to be restored to an undeformed state, thereby biasing the electrode terminal (50) inward and causing the outer flange portion (50b) to come into contact with the outer surface (52a) of the battery housing (51) to induce a short circuit.

[0166] According to one aspect of the present invention, the shape-deforming member (58) may be made of steel, SUS, stainless steel, etc.

[0167] According to one aspect of the present invention, the shape-deforming member (58) may be composed of or include a conductive material so as to be electrically connected to a contacted conductive member. Alternatively, the shape-deforming member (58) may be composed of or include an electrically neutral dielectric material. For example, if the shape-deforming member (58) is conductive, the shape-deforming member (58) arranged as shown in FIGS. 5 to 6b and FIGS. 7a and 7b may be electrically connected to an electrode terminal (50). In this case, the shape-deforming member (58) is preferably shaped and sized such that the height difference (d) between one end (58a) and the other end (58b) is greater than or equal to the thickness of the outer gasket (54b) of the terminal gasket (54). In this way, when a portion of the terminal gasket (54), for example, the outer gasket (54b), is melted, the shape-deforming member (58) is elastically restored to a thickness greater than that of the outer gasket (54b), so that electrical contact can be formed through the shape-deforming member (58) between the outer flange portion (50b) of the electrode terminal (50) and the outer surface (52a) of the end wall (52) of the battery housing (51). Even in this case, it is more preferable that the height difference (d) be greater than the total thickness of the outer gasket (54b) and the inner gasket (54a). Meanwhile, even when the shape-deforming member (58) is electrically neutral, it is preferable that the size and shape be set so that the height difference (d) is greater than the thickness of the outer gasket (54b), and more preferably greater than the total thickness of the outer gasket (54b) and the inner gasket (54a). In this way, even if the shape-deformed member (58) itself does not conduct electricity between the outer flange portion (50b) of the electrode terminal (50) and the outer surface (52a) of the end wall (52) of the battery housing (51), the shape-deformed member (58) can be restored to an undeformed state and the electrode terminal (50) can be induced to come into direct contact with the end wall (52).

[0168] According to another aspect of the present invention (not shown), a shape-deforming member (58) may be disposed between an external gasket (54b) and an outer surface (52a) of an end wall (52) of a battery housing (51), and in this case, may be electrically connected to the battery housing (51). In this case, the shape-deforming member (58) is preferably shaped and sized such that the height difference (d) between one end (58a) and the other end (58b) is greater than or equal to the thickness of the external gasket (54b) of the terminal gasket (54). In this way, when a portion of the terminal gasket (54), for example, the outer gasket (54b), is melted, the shape-deformed member (58) elastically restores to a thickness greater than that of the outer gasket (54b), thereby forming an electrical contact through the shape-deformed member (58) between the outer flange portion (50b) of the electrode terminal (50) and the outer surface (52a) of the end wall (52) of the battery housing (51), and a short circuit may occur as the portion of the terminal gasket (54) is melted and the electrode terminal (50) and the shape-deformed member (58) come into contact with each other.

[0169] Preferably, the fixing structure of the electrode terminal (50, 50') according to the aspects of the present invention described above can be applied to a cylindrical battery with a form factor greater than 2170.

[0170] Recently, as cylindrical batteries are being applied to electric vehicles, the form factor of cylindrical batteries is increasing compared to conventional 1865, 2170, etc. The increase in form factor leads to increased energy density, enhanced safety against thermal runaway, and improved cooling efficiency.

[0171] Additionally, as described below, a cylindrical battery including a fixed structure of electrode terminals (50, 50') can enable more efficient electrical wiring by arranging electrical terminals of different polarities adjacently (e.g., electrical terminals defined by adjacent end walls (52) of the battery housing (51)). Furthermore, since the electrode terminals (50, 50') have a large cross-sectional area and low resistance, they are suitable for rapid charging.

[0172] Preferably, the cylindrical battery to which the electrode terminal (50, 50') structure of the present invention is applied may be, for example, a cylindrical battery in which the ratio of the form factor (defined as the ratio of the diameter of the cylindrical battery to the height, i.e., the ratio of the diameter (Φ) to the height (H)) is approximately greater than 0.4.

[0173] Here, the form factor refers to a value representing the diameter and height of a cylindrical battery. The form factor of a cylindrical battery according to one aspect of the present invention may be, for example, 4611, 4875, 48110, 4880, or 4680. In the numerical value representing the form factor, the first two digits represent the diameter of the battery, and the remaining digit represents the height of the battery.

[0174] A battery according to one aspect of the present invention may be a cylindrical battery having a diameter of approximately 46 mm, a height of approximately 110 mm, and a form factor ratio of 0.418.

[0175] A battery according to another aspect may be a cylindrical battery with a diameter of approximately 48 mm, a height of approximately 75 mm, and a form factor ratio of 0.640.

[0176] According to another aspect, the battery may be a cylindrical battery with a diameter of approximately 48 mm, a height of approximately 110 mm, and a form factor ratio of 0.436.

[0177] According to another aspect, the battery may be a cylindrical battery with a diameter of approximately 48 mm, a height of approximately 80 mm, and a form factor ratio of 0.600.

[0178] According to another aspect, the battery may be a cylindrical battery with a diameter of approximately 46 mm, a height of approximately 80 mm, and a form factor ratio of 0.575.

[0179] Conventionally, batteries with a form factor ratio of approximately 0.4 or less were used. That is, conventionally, for example, 1865 and 2170 batteries were used. In the case of the 1865 battery, its diameter is approximately 18 mm, its height is approximately 65 mm, and its form factor ratio is 0.277. In the case of the 2170 battery, its diameter is approximately 21 mm, its height is approximately 70 mm, and its form factor ratio is 0.300.

[0180]

[0181] FIG. 7a is a cross-sectional view of a cylindrical battery (70) according to one aspect of the present invention, cut along the length direction (Y).

[0182] Referring to FIG. 7a, a cylindrical battery (70) according to one side includes a jelly roll type electrode assembly (71) in which a sheet-shaped first electrode and a second electrode are wound with a separator interposed therein, and a non-exposed portion (72) of the first electrode is exposed as a first portion of the first electrode at the bottom and a non-exposed portion (73) of the second electrode is exposed as a second portion of the second electrode at the top.

[0183] Here, it should be noted that the “first part” and “second part” of the electrode may be other parts of the electrode other than the unoccupied part. For example, these parts may include a metal tab electrically connected to the unoccupied part of the electrode. Additionally, the electrode assembly (71) may have a shape other than a jelly roll shape. For example, in addition to a cylindrical shape, the battery may have a prismatic shape or various other shapes.

[0184] In one aspect of the present invention, the first electrode may be a negative electrode and the second electrode may be a positive electrode. Of course, the opposite is also possible.

[0185] The winding method of the electrode assembly (71) may be substantially the same as the winding method of the electrode assembly used in the manufacture of a tap-less cylindrical battery according to the prior art described with reference to FIG. 2.

[0186] In illustrating the electrode assembly (71), only the unwound portions (72, 73) that are exposed and extended to the outside of the separator are illustrated in detail, and the illustration of the winding structure of the first electrode, the second electrode, and the separator is omitted.

[0187] The cylindrical battery (70) also includes a cylindrical battery housing (51) that accommodates an electrode assembly (71) and is electrically connected to the unoccupied portion (72) of the first electrode.

[0188] Preferably, one side (top) of the battery housing (51) is open. Additionally, the end wall (52) of the battery housing (51) has a structure in which the electrode terminal (50) is riveted into the through hole (53) through a firing (e.g., corking) process.

[0189] The electrode terminal (50) may include a body portion (50a) inserted into a through hole (53), an outer flange portion (50b) extending along the outer surface (52a) from the first side perimeter of the body portion (50a) exposed through the outer surface (52a) of the end wall (52) of the battery housing (51), an inner flange portion (50c) extending toward the inner surface (52b) from the second side perimeter of the body portion (50a) exposed through the inner surface (52b) of the end wall (52) of the battery housing (51), and optionally, a flat portion (50d) provided on the inner side of the inner flange portion (50c) and surrounded by the inner flange portion (50c).

[0190] The electrode terminal (50) can be replaced with the electrode terminal (50') structure shown in FIG. 6b.

[0191] The cylindrical battery (70) may also include a terminal gasket (54) interposed between the electrode terminal (50) and the through hole (53).

[0192] Specifically, the cylindrical battery (70) may also include a seal (74) that seals the open end of the battery housing (51) so as to be insulated from the battery housing (51). Preferably, the seal (74) may include a non-polar, plate-shaped cap (74a) and a sealing gasket (74b) interposed between the edge of the cap (74a) and the open end region of the battery housing (51).

[0193] The cap (74a) may be made of a conductive metal material such as aluminum, steel, or nickel. Additionally, the sealing gasket (74b) may preferably be made of insulating and elastic polypropylene, polybutylene terephthalate, polyfluoroethylene, etc. However, the present invention is not limited by the materials of the cap (74a) and the sealing gasket (74b).

[0194] The cap (74a) may be configured to include a vent notch (77) that ruptures when the pressure inside the battery housing (51) exceeds a critical threshold. The vent notch (77) may be formed on both sides of the cap (74a). The vent notch (77) may form a continuous or discontinuous circular pattern, a straight pattern, or other pattern on the surface of the cap (74a). The depth and width of the vent notch (77) may be such that the pressure inside the battery housing (51) is 15 kgf / cm² 2 Up to 35 kgf / cm² 2 It can be set to rupture when within the range.

[0195] The battery housing (51) may include a crimping portion (75) that is radially folded inward to wrap around the edge of the cap (74a) together with a sealing gasket (74b) to secure the seal (74) extending from the battery housing (51).

[0196] Preferably, the lower surface of the cap (74a) can be positioned higher than the bottom of the crimping portion (75) (i.e., further away from the electrode assembly (71)). Then, a vent space is formed in the lower part of the cap (74a) so that gas can be discharged smoothly when the vent notch (77) is ruptured.

[0197] The battery housing (51) may also include a beading portion (76) pressed into the interior of the battery housing (51) in an area adjacent to the open end. The beading portion (76) supports the edge of the seal (74), particularly the outer surface of the sealing gasket (74b), when the seal (74) is secured by the crimping portion (75).

[0198] The cylindrical battery (70) may also further include a first current collector (78) welded to the non-bonded portion (72) of the first electrode. The first current collector (78) is made of a conductive metal material such as aluminum, steel, or nickel. Preferably, at least a portion (78a) of the edge of the first current collector (78) that does not contact the non-bonded portion (72) of the first electrode may be interposed between the beading portion (76) and the sealing gasket (74b) and secured by the crimping portion (75). Optionally, at least a portion (78a) of the edge of the first current collector (78) may be secured by welding to the inner circumference (76a) of the beading portion (76) adjacent to the crimping portion (75).

[0199] The cylindrical battery (70) may also include a second current collector (79) that is welded to the unbonded portion (73) of the second electrode. Preferably, at least a portion of the second current collector (79), such as the central portion (79a), may be welded to the flat portion (50d) of the electrode terminal (50).

[0200] Preferably, when welding the second current collector (79), the welding tool can be inserted through the welding hole (80a) formed in the core of the electrode assembly (71) to reach the welding point of the second current collector (79). That is, this welding can be performed by inserting the welding tool into the welding hole (80a) through the open end of the battery housing (51) before fixing the seal (74) to the open end of the battery housing (51).

[0201] When the second current collector (79) is welded to the flat portion (50d) of the electrode terminal (50), the electrode terminal (50) supports the welding area of ​​the second current collector (79), thereby applying strong pressure to the welding area to improve welding quality. Additionally, since the flat portion (50d) of the electrode terminal (50) has a large surface area, the welding area can also be secured widely. By doing so, the internal resistance of the cylindrical battery (70) can be lowered by lowering the contact resistance of the welding area. The face-to-face welding structure of the riveted electrode terminal (50) and the second current collector (79) is very useful for rapid charging using high C-rate current. This is because the amount of heat generated in the current path can be lowered compared to conventional methods, as the current density per unit area can be lowered in the cross-section in the direction of current flow.

[0202] When welding the flat portion (50d) of the electrode terminal (50) and the second current collector (79), any one of laser welding, ultrasonic welding, spot welding, and resistance welding may be used.

[0203] The cylindrical battery (70) may also further include an insulator (80). The insulator (80) may be interposed between the second current collector (79) and the inner surface (52b) of the end wall (52) of the battery housing (51), and between the inner circumferential surface (51a) of the side wall of the battery housing (51) and the electrode assembly (71).

[0204] Preferably, the insulator (80) may include a welding hole (80a) that exposes the flat portion (50d) of the electrode terminal (50) toward the second current collector (79). Additionally, the welding hole (80a) may expose the inner flange portion (50c) and the inner gasket (54a) together with the flat portion (50d) of the electrode terminal.

[0205] Preferably, the insulator (80) can cover at least the axial end of the electrode assembly (71) closest to the surface of the second current collector (79) and the end wall (52) of the battery housing (51). Thus, the insulator (80) can preferably prevent contact between the battery housing (51) and the unincorporated portion (73) of the second current collector (79) or the second electrode, which have different polarities.

[0206] Preferably, the insulator (80) is made of an insulating resin and may include an upper plate (80b) and a side sleeve (80c). In one example, the upper plate (80b) and the side sleeve (80c) may be formed as a single member through integrated injection molding. Alternatively, the side sleeve (80c) may be replaced with insulating tape, etc. The insulating tape may cover the outer edge of the second current collector (79) together with the uninsulated portion (73) of the second electrode exposed through the outer surface of the electrode assembly (71).

[0207] Preferably, the inner surface (52b) of the end wall (52) of the battery housing (51) and the insulator (80) may be in close contact as shown in FIG. 7b. Here, "close contact" means a state in which there is no gap (space) visible to the naked eye. To reduce the gap (space) between the insulator (80) and the inner surface (52b), the distance from the inner surface (52b) of the end wall (52) of the battery housing (51) to the flat portion (50d) of the electrode terminal (50) may be set to be equal to or slightly smaller than the thickness of the insulator (80).

[0208] Preferably, the uncoated portions (72, 73) of the first electrode and / or the second electrode may be bent in the radial direction of the electrode assembly (71), for example, from the outer periphery side to the core side, thereby forming a bent surface on the upper and lower parts of the electrode assembly (71). Additionally, the first current collector (78) may be welded to the bent surface formed by bending the uncoated portion (72) of the first electrode, and the second current collector (79) may be welded to the bent surface formed by bending the uncoated portion (73) of the second electrode.

[0209] To relieve stress generated when bending the non-reinforced portion (72, 73), the first electrode and / or the second electrode may have an improved structure different from the conventional electrode shown in FIG. 1, and this is described below.

[0210] FIG. 8 is a plan view illustrating an exemplary unfolded structure of an electrode (90) according to one aspect of the present invention.

[0211] Referring to FIG. 8, the electrode (90) includes a sheet-shaped current collector (91) made of a conductive foil, and an active material layer (92) is applied to at least one surface of the current collector (91). Accordingly, a non-active portion (93) is defined along one long side of the current collector (91) where the active material is not applied.

[0212] Preferably, the unsold portion (93) may include a plurality of segment (93a) structures. The plurality of segments (93a) may form a plurality of groups, and the segments (93a) included within each group may have the same height (axial Y length) and / or the same width (winding X length) and / or the same pitch (angle formed by the side with respect to the X direction). The number of segments (93a) in each group may be greater or less than the number shown in FIG. 8. Each segment (93a) may have a geometric shape defined by a combination of at least one straight line and / or curve. Preferably, each segment (93a) may be trapezoidal in shape, but may be changed to a square, rectangle, parallelogram, semicircle, semi-ellipse, or a shape similar to a semi-ellipse.

[0213] Preferably, the height of the segment (93a) may increase stepwise along one direction parallel to the winding direction of the electrode assembly, for example, from the core side to the outer side. Additionally, the core-side unoccupied portion (93') adjacent to the core side may not contain the segment (93a), and the height of the core-side unoccupied portion (93') may be smaller than other unoccupied portion areas. Additionally, the outer-side unoccupied portion (93'') adjacent to the outer side may not contain the segment (93a), and the height of the outer-side unoccupied portion (93'') may be smaller than other unoccupied portion areas.

[0214] Optionally, the electrode (90) may include an insulating coating layer (94) covering the boundary between the active material layer (92) and the non-active portion (93). The insulating coating layer (94) comprises a polymer resin having electrical insulating properties and may optionally additionally include an inorganic filler. The insulating coating layer (94) serves to prevent contact between the edge of the active material layer (92) and the active material layer of the electrode of opposite polarity located on the opposite side of the interposed separator, and also serves to structurally support the segment (93a) bent in the axial direction (Y). To this end, when the electrode (90) is wound into an electrode assembly, it is preferable that at least a portion of the insulating coating layer (94) be exposed beyond the edge of the adjacent separator.

[0215] FIG. 9 is a cross-sectional view taken along the longitudinal direction (Y) of an electrode assembly (100) in which a non-partial segmental structure of an electrode (90) according to one aspect of the present invention is applied to a first electrode and a second electrode.

[0216] Referring to FIG. 9, the electrode assembly (100) can be manufactured by a winding method as described in FIG. 2. For convenience of explanation, the protruding structure of the unwound portions (72, 73) protruding beyond the edge of the separator is shown in detail, and the winding structure of the first electrode, the second electrode, and the separator is omitted from the illustration. It should be noted that the unwound portion (72) protruding downward extends from the first electrode, and the unwound portion (73) protruding upward extends from the second electrode.

[0217] The pattern of change in the height of the unsold portions (72, 73) is schematically illustrated. That is, the height of the unsold portions (72, 73) may change irregularly depending on the location where the cross-section is cut. For example, if the side portion of the trapezoidal segment (93a) is cut, the height of the unsold portion in the cross-section may be lower than the total height of the segment (93a). Therefore, it should be understood that the height of the unsold portions (72, 73) illustrated in the drawing showing the cross-section of the electrode assembly (100) corresponds to the average of the unsold portion heights included in each winding turn.

[0218] The unbent portions (72, 73) can be folded along the radial direction of the electrode assembly (100), for example, from the outer side to the core side, as shown in FIG. 10a and FIG. 10b. In FIG. 9, the portion being folded (101) is indicated by a dotted box. When the unbent portions (72, 73) are folded, the segments adjacent in the radial direction overlap each other in multiple layers, and a fold surface (102) is formed on the upper and lower parts of the electrode assembly (100). At this time, the core-side unbent portion (93' in FIG. 8) is not folded because its height is low, and the height (h) of the segment that is folded at the innermost part is equal to or smaller than the radial length (r) of the winding area formed by the core-side unbent portion (93') that does not have a segment structure. Therefore, since the welding hole (80a) is not closed, no additional difficulty is added when performing the electrolyte injection process, and the electrolyte injection efficiency can be maintained at a high level. In addition, by inserting the welding tool through the welding hole (80a), welding of the electrode terminal (50) and the second current collector (79) can also be easily performed.

[0219] In one aspect of the present invention, the cap (74a) of the seal (74) of the cylindrical battery (70) does not have polarity. Instead, the first current collector (78) is connected to the side wall of the battery housing (51), so that the outer surface (52a) of the end wall (52) of the battery housing (51) has polarity opposite to that of the electrode terminal (50). Therefore, when connecting multiple batteries in series and / or parallel, wiring such as busbar connection can be performed on the upper part of the cylindrical battery (70) using the outer surface (52a) of the end wall (52) of the battery housing (51) and the electrode terminal (50). Through this, the number of batteries that can be mounted in the same space can be increased to improve energy density, and electrical wiring work can be performed easily.

[0220] In the present invention, the positive active material coated on the positive electrode and the negative active material coated on the negative electrode may be used without limitation as long as they are active materials known in the art.

[0221] In one example, the positive active material is the general chemical formula A[A x M y ]O 2+z It may include an alkali metal compound represented by (A contains at least one element among Li, Na and K; M contains at least one element selected from Ni, Co, Mn, Ca, Mg, Al, Ti, Si, Fe, Mo, V, Zr, Zn, Cu, Al, Mo, Sc, Zr, Ru, and Cr; x ≥ 0, 1 ≤ x+y ≤ 2, -0.1 ≤ z ≤ 2; the stoichiometric coefficients of the components included in x, y, z and M are selected so that the compound maintains electrical neutrality).

[0222] In another example, the positive active material is an alkali metal compound xLiM disclosed in US6,677,082, US6,680,143, etc. 1 O2-(1-x)Li2M 2 O3(M 1 It comprises at least one element having an average oxidation state of 3; M2 It contains at least one element having an average oxidation state of 4; 0≤x≤1).

[0223] In another example, the positive active material is, with the general chemical formula Li a M 1 x Fe 1-x M 2 y P 1-y M 3 z O 4-z (M 1 It comprises at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, and Al; M 2 ... comprises at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, Al, As, Sb, Si, Ge, V, and S; M 3 ... comprises a halogen element optionally containing F; 0 < a ≤ 2, 0 ≤ x ≤ 1, 0 ≤ y < 1, 0 ≤ z < 1; a, x, y, z, M 1 , M 2 , and M 3 The stoichiometric coefficient of the component included in the compound is selected so that the compound maintains electrical neutrality), or may be a lithium metal phosphate represented as Li3M2(PO4)3 [M comprises at least one element selected from Ti, Si, Mn, Fe, Co, V, Cr, Mo, Ni, Al, Mg and Al].

[0224] Preferably, the positive active material may include primary particles and / or secondary particles formed by the aggregation of primary particles.

[0225] In one example, the negative electrode active material may be a carbon material, lithium metal or lithium metal compound, silicon or silicon compound, tin or tin compound, etc. Metal oxides such as TiO2 and SnO2 with a potential of less than 2V may also be used as negative electrode active materials. As for the carbon material, low-crystallinity carbon, high-crystallinity carbon, etc. may all be used.

[0226] The separator may be a porous polymer film, such as a polyolefin-based polymer like ethylene homopolymer, propylene homopolymer, ethylene / butene copolymer, ethylene / hexene copolymer, or ethylene / methacrylate copolymer, used alone or in a laminate thereof. As another example, the separator may be a conventional porous nonwoven fabric, such as a nonwoven fabric made of high-melting-point glass fibers or polyethylene terephthalate fibers.

[0227] At least one surface of the separation membrane may include a coating layer of inorganic particles. It is also possible for the separation membrane itself to consist of a coating layer of inorganic particles. The particles constituting the coating layer may have a structure bonded with a binder such that interstitial volume exists between adjacent particles.

[0228] The inorganic particles may be composed of inorganic materials having a dielectric constant of 5 or higher. As a non-limiting example, the inorganic particles are Pb(Zr,Ti)O3(PZT), Pb 1-x La x Zr 1-y Ti y O3(PLZT), PB(Mg3Nb 2 / 3 It may include at least one material selected from the group consisting of )O3-PbTiO3(PMN-PT), BaTiO3, hafnia (HfO2), SrTiO3, TiO2, Al2O3, ZrO2, SnO2, CeO2, MgO, CaO, ZnO, and Y2O3.

[0229] The electrolyte is A + B- It may be a salt having a structure like that. Here, A + is Li + , Na + , K + It includes alkali metal cations such as or ions composed of combinations thereof. And B - is F - , Cl - , Br - , I - , NO3 - , N(CN)2 - , BF4 - , ClO4 - , AlO4 - , AlCl4 - , PF6 - , SbF6 - , AsF6 - , BF2C2O4 - , BC4O8 - , (CF3)2PF4 - , (CF3)3PF3 - , (CF3)4PF2 - , (CF3)5PF - , (CF3)6P - , CF3SO3 - , C4F9SO3 - , CF3CF2SO3 - , (CF3SO2)2N - , (FSO2)2N - ,　 CF3CF2(CF3)2CO - , (CF3SO2)2CH - , (SF5)3C - , (CF3SO2)3C - , CF3(CF2)7SO3 - , CF3CO2 - , CH3CO2 - ,SCN - and (CF3CF2SO2)2N - It includes one or more anions selected from the group consisting of

[0230] The electrolyte can also be used by dissolving it in an organic solvent. As organic solvents, propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, tetrahydrofuran, N-methyl-2-pyrrolidone (NMP), ethyl methyl carbonate (EMC), gamma-butyrolactone (γ-butyrolactone), or mixtures thereof may be used.

[0231] A cylindrical battery (70) according to one aspect described above can be used to manufacture a battery pack.

[0232] FIG. 11 is a schematic diagram showing the configuration of a battery pack according to one aspect of the present invention.

[0233] Referring to FIG. 11, a battery pack (200) according to one aspect of the present invention comprises an assembly of electrically connected cylindrical batteries (201) and a pack housing (202) that accommodates the same. The cylindrical batteries (201) may be batteries according to the one aspect described above. In the drawings, for convenience of drawing, components such as a busbar, a cooling unit, and an external terminal for electrically connecting the cylindrical batteries (201) are omitted.

[0234] The battery pack (200) can be mounted on a vehicle. The vehicle may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle includes a four-wheeled vehicle or a two-wheeled vehicle.

[0235] FIG. 12 is a drawing for explaining a vehicle including the battery pack (200) of FIG. 11.

[0236] Referring to FIG. 12, a vehicle (V) according to one aspect of the present invention includes a battery pack (200) according to one aspect of the present invention. The vehicle (V) operates by receiving power from the battery pack (200) according to one aspect of the present invention.

[0237] Although the present invention has been described above with respect to limited aspects and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

Claims

1. As a subassembly of a battery, A battery housing having an internal space configured to accommodate at least a portion of an electrode assembly therein, extending in an axial direction, having an open end region on a first side along the axial direction and a closed end region on the opposite second side, wherein the closed end region is formed by an end wall having a through hole; Terminal gasket disposed within the above-mentioned through hole; An electrode terminal disposed within the terminal gasket, spaced apart from the end wall of the battery housing by the terminal gasket, and exposed to the outside of the battery housing; and A subassembly characterized by including a shape-deforming member disposed between the end wall and the electrode terminal, which applies force in the direction of the end wall to at least a portion of the electrode terminal.

2. In Claim 1, The above electrode terminal is, A body portion disposed in the above-mentioned through hole; An outer flange portion extending radially outward from the outer end of the body portion; and A subassembly characterized by including an inner flange portion extending radially outward from the inner end of the body portion.

3. In Claim 2, A subassembly characterized in that the body portion, the outer flange portion, and the inner flange portion are integrally formed as an integrated structure.

4. In Claim 2, A subassembly characterized in that the inner surface of the inner flange portion defines a flat weld.

5. In Claim 2, The above terminal gasket is, An external gasket interposed between the outer flange portion and the outer surface of the end wall of the battery housing; An internal gasket interposed between the inner flange portion and the inner surface of the end wall of the battery housing; and A subassembly characterized by including an intermediate gasket that extends between the body portion and the end wall of the battery housing and connects the outer gasket and the inner gasket.

6. In Claim 5, A subassembly characterized in that the above-mentioned shape-deforming member is interposed between the above-mentioned outer flange portion and the above-mentioned outer gasket.

7. In Claim 5, A subassembly characterized in that the above-described shape-deforming member is interposed between the outer surface of the end wall of the battery housing and the outer gasket.

8. In Claim 1, A subassembly characterized in that the shape deformation member comprises an elastic bias member or a temperature-responsive deformation member.

9. In Claim 1, The above elastic bias member includes an elastic bias member, and A subassembly characterized in that the above elastic bias member is a spring washer.

10. In Claim 1, A subassembly characterized in that the battery housing is cylindrical in shape.

11. In Claim 1, The above-mentioned shape-deforming member includes an elastic bias member, and A subassembly characterized in that the above elastic bias member is positioned in a compressed state biased to expand into a shape that is not deformed by a predetermined amount of displacement along the axial direction.

12. In Claim 1, A subassembly characterized in that the above-mentioned shape-deforming member is positioned in a biased state to expand into a shape that is not deformed by a predetermined amount of displacement along the axial direction.

13. In Claim 11, A subassembly characterized in that the above displacement amount is greater than or equal to the thickness of the terminal gasket.

14. In Claim 13, A subassembly characterized in that the above displacement amount is greater than or equal to the total thickness of all parts of the terminal gasket along the axial direction.

15. In Claim 1, A subassembly characterized in that the above-mentioned shape-deformed member is conductive.

16. In Claim 1, A subassembly characterized in that the melting point of the shape-deformed member is higher than the melting point of the terminal gasket.

17. As a battery, A subassembly according to claim 1; and A battery characterized by comprising: an electrode assembly that is accommodated within the internal space of the battery housing, wherein a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode are wound together, and wherein the first electrode is electrically connected to the battery housing and the second electrode is electrically connected to an electrode terminal.

18. In Claim 17, A battery characterized by further including a sealing body located on and sealing the open end region of the battery housing.

19. In Claim 18, A battery characterized in that the battery housing further includes a crimping portion extending inwardly in radius to surround the edge of the seal.

20. A battery pack comprising a battery according to claim 17.

21. An automobile comprising a battery pack according to claim 20.