Cylindrical battery cells have the ability to cool the bottom.

Abstract

The invention relates to a cylindrical battery cell with a structure capable of rapid cooling through the bottom of the can, a battery assembly comprising the battery cell with a bottom cooling structure, and a vehicle comprising the battery assembly as a power source. The battery cell comprises a can with an axially elongated side wall, an opening present at the first end of the side wall, and the bottom connected to the second end of the side wall; an electrode assembly comprising a first and second electrode, the electrode assembly contained within the can; a cover covering the opening of the can and electrically connected to the first end of the side wall; and the first electrode tip installed at the center of the cover and insulated from the cover, such that the first electrode is electrically connected to the first electrode tip, and the second electrode is electrically connected to the can and the cover.

Description

Cylindrical battery cells with bottom cooling

[0001] The present invention relates to a cylindrical battery cell, and more particularly, to a cylindrical battery cell having a structure that enables smooth cooling through a bottom member of a can.

[0002] This application claims priority to Korean Application No. 10-2024-0068042, filed May 24, 2024, the entire disclosure of which is incorporated herein by reference.

[0003] With the proliferation of electric vehicles, the capacity of cylindrical battery cells, manufactured using cylindrical battery cans as housings, is increasing. Furthermore, as battery cell sizes increase, it has become possible to position both the first and second electrode terminals on the top surface of a cylindrical battery cell. With both electrode terminals positioned on the top of the battery cell, multiple cylindrical battery cells can be mounted vertically, and bus bars for both electrode terminals can be positioned on top of the battery cells, further simplifying the structure of vehicle battery packs.

[0004] Referring to Fig. 1, a can (10) of a conventional large-capacity cylindrical battery cell has a bottom member (12) positioned at the top and an opening formed at the lower end of a side wall member (11). A first electrode terminal (17) is sealedly installed in the center of the bottom member (12) with a terminal gasket (18) interposed therebetween.

[0005] In a state where the electrode assembly (20) is accommodated inside the can (10), the first collector plate (30) bonded to the first electrode of the electrode assembly (20) is electrically connected by being bonded to the first electrode terminal (17), and the second collector plate (40) bonded to the second electrode of the electrode assembly (20) is electrically connected by being bonded to the beading portion (113) formed at the lower end of the side wall member (11) of the can (10). Accordingly, the bottom member (12) and the side wall member (11) can form a second electrode terminal (14).

[0006] The cap (16) is attached to the lower end of the side wall member (11) to close the opening of the can (10). The edge of the cap (16) is installed by compression between the beading portion (113) and the crimping portion (115) of the side wall member (11) with the cap gasket (15) interposed therebetween. The cap (16) is not charged by the cap gasket (15) and can thus be non-polar.

[0007] However, since the cap (16) of such a battery cell is placed at the bottom of the can (10) and the air gap between the cap (16) and the electrode assembly (20) acts as a kind of insulating layer, it is impossible to cool the battery cell from the bottom when the battery cell is installed in a battery pack in an upright position.

[0008] Accordingly, the battery cell structure described above inevitably requires side cooling via the sidewall member (11). This limitation in battery cell cooling significantly limits the design freedom of the battery pack. For example, it prevents the application of a battery pack structure that allows bottom cooling.

[0009] The present invention has been derived to solve the above-described problem, and aims to provide a battery cell having a structure in which both the first electrode terminal and the second electrode terminal are positioned at the top, while allowing bottom cooling.

[0010] The present invention aims to provide a battery pack in which both the first electrode terminal and the second electrode terminal of the battery cell built in the battery pack are disposed at the top and bottom cooling is possible, and an automobile equipped with the battery pack.

[0011] The technical objectives of the present invention are not limited to the purposes mentioned above. Other objectives and advantages of the present invention not mentioned above can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the objectives and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0012] The present invention, which aims to solve the above-described problem, can be applied to a cylindrical battery cell in which both the first electrode terminal and the second electrode terminal are provided at the axial first end.

[0013] The above battery cell may have a can having a side wall member extending in the axial direction, an opening provided at a first end of the side wall member, and a bottom member connected to a second end of the side wall member.

[0014] The above can may be cylindrical.

[0015] The above battery cell may include a first electrode and a second electrode, and may include an electrode assembly built into the can.

[0016] The above electrode assembly is supported with the surface facing the floor member in contact with the floor member.

[0017] The above battery cell may have a cap covering the opening of the can.

[0018] The above battery cell includes a first electrode terminal installed in the cap.

[0019] The above first electrode terminal can be installed through a hole provided in the cap.

[0020] The above first electrode terminal can be installed in the central portion of the cap.

[0021] The above first electrode terminal is installed so as to be electrically insulated from the cap.

[0022] The edge portion of the above cap can be joined to the first end portion of the side wall member.

[0023] The edge portion of the cap may be welded to the axial first end portion of the side wall member to seal the can.

[0024] The edge portion of the above cap can be electrically connected by welding to the side wall member.

[0025] The above welding may be a seam welding. The above welding may be performed by a laser.

[0026] The first electrode is electrically connected to the first electrode terminal, and the second electrode is electrically connected to the can and the cap.

[0027] Accordingly, the first electrode terminal may have a first polarity, and the can and cap may have a second polarity.

[0028] The above electrode assembly may have a structure in which a separator is interposed between the first electrode and the second electrode and is wound around the core cavity.

[0029] The above-mentioned core hollow portion can be extended in the axial direction.

[0030] The above electrode assembly may have a first electrode tab electrically connected to the first electrode.

[0031] The above first electrode tab can be arranged at the axial first end of the electrode assembly.

[0032] The above first electrode tab can be electrically connected by being joined to the first electrode terminal.

[0033] The above first electrode may protrude axially outward from the axial first end of the electrode assembly and be bent radially, thereby providing a first surface whose surface faces axially outward.

[0034] The above first electrode can be electrically connected to the first electrode terminal through the first collector plate.

[0035] The above first collector plate may have a first electrode connection portion connected to the first electrode and a first terminal connection portion connected to the first electrode terminal.

[0036] The above first terminal connection portion may be thin for flexibility and may extend long from the first electrode connection portion.

[0037] The first electrode connection portion of the first collector plate is bonded to the first surface, so that the first electrode and the first collector plate can be electrically connected.

[0038] An electrically insulating insulator may be interposed between the cap and the electrode assembly in the axial direction.

[0039] The above insulator can be interposed between the cap and the first electrode connection portion in the axial direction.

[0040] The above electrode assembly may have a second electrode tab electrically connected to the second electrode.

[0041] The above second electrode tab can be arranged at the axial second end of the electrode assembly.

[0042] The above second electrode tab can be electrically connected by being bonded to the floor member.

[0043] The second electrode may protrude axially outward from the axial second end of the electrode assembly and be bent radially to provide a second surface whose surface faces axially outward.

[0044] The second electrode may be electrically connected to the can via a second collector plate.

[0045] The second collector plate may have a second electrode connection portion connected to the second electrode and a second terminal connection portion connected to the bottom member of the can.

[0046] The second electrode connection portion of the second collector plate is bonded to the second surface, so that the second electrode and the second collector plate can be electrically connected.

[0047] The above second surface can be in contact with the floor member with the second collector plate interposed therebetween in the axial direction.

[0048] The second surface may be in contact with the second collector plate and may face each other in the axial direction, and the second collector plate may be in contact with the floor member and may face each other in the axial direction.

[0049] A vent notch is provided radially inward from the edge portion to reduce the thickness of the cap. Accordingly, when the internal pressure of the battery cell increases, the vent notch is ruptured, opening the cap body, thereby preventing an explosion of the battery cell.

[0050] The present invention provides a battery pack having a pack case that houses the battery cell.

[0051] The battery cell may be built into the pack case such that the bottom member is in contact with the bottom of the pack case and the cap faces upward.

[0052] A cooling structure may be provided on the bottom of the above pack case to cool the battery cell through the bottom member of the battery cell.

[0053] The present invention provides a vehicle equipped with a battery pack and driven by power from the battery pack.

[0054] The battery cell of the present invention has a structure in which the first electrode terminal is installed in a cap in an insulated and sealed manner, and the cap is sealed and fixed so as to be electrically connected to the can, so that both the first electrode terminal and the second electrode terminal are positioned at the top, while allowing bottom cooling.

[0055] The present invention has a structure in which cooling of the bottom of the electrode assembly is possible because the surface of the electrode assembly facing the bottom member of the can is in contact with the bottom member of the can.

[0056] In the battery cell of the present invention, since the second electrode is bent radially inward at the second end of the electrode assembly and comes into contact with the bottom member of the can through the second collector plate, heat generated in the electrode assembly can be quickly dissipated toward the lower part of the battery cell by sequentially passing through the second electrode, the second collector plate, and the bottom member.

[0057] A battery pack equipped with a battery cell of the present invention can apply a lower cooling structure.

[0058] In addition to the effects described above, specific effects of the present invention are described below while explaining specific details for carrying out the invention.

[0059] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the contents of the invention described above, serve to further understand the technical concept of the present invention. Therefore, the present invention should not be interpreted as being limited to the matters described in these drawings. Meanwhile, the shape, size, scale, or ratio of elements in the drawings included in this specification may be exaggerated to emphasize a clearer explanation.

[0060] Figure 1 is a cross-sectional view showing a comparative form of a cylindrical battery cell.

[0061] Figure 2 is an exploded perspective view of the electrode assembly accommodated inside the can of Figure 1 before winding.

[0062] Fig. 3 is a perspective view of the electrode assembly of Fig. 2 in a pre-winding laminated state.

[0063] Fig. 4 is a perspective view of an assembled cylindrical jelly-roll-shaped electrode assembly by winding up the laminate of Fig. 3.

[0064] Figure 5 is a perspective view showing a state in which a first collector plate is joined to an electrode tab provided at an axial first end of an electrode assembly facing the opening of a can.

[0065] Figure 6 is a perspective view showing a state in which a second collector plate is joined to an electrode tab provided on the axial second end of the electrode assembly facing the bottom member of the can.

[0066] Fig. 7 is a perspective view showing a state in which a cap is bonded to the first collector plate of the electrode assembly of Fig. 5.

[0067] Figure 8a is a cross-sectional view showing a state in which an electrode assembly is inserted into a can so that the second collector plate is in contact with the bottom member and the first collector plate and cap are positioned toward the opening, and the cap is bonded to the inner surface of the side wall member.

[0068] Figure 8b is a cross-sectional view showing a state in which the electrode assembly is inserted into the can so that the second collector plate is in contact with the bottom member and the first collector plate and cap are positioned toward the opening, and the cap is bonded to the upper side of the side wall member.

[0069] FIG. 9 is a drawing showing a battery pack having the battery cell of FIG. 8 built into a pack housing.

[0070] Fig. 10 is a drawing showing a vehicle equipped with the battery pack of Fig. 9.

[0071] Hereinafter, the present invention will be described in detail with reference to the drawings. Terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concept of a term to best explain his or her invention, they should be interpreted in the sense and concept consistent with the technical spirit of the present invention.

[0072] Accordingly, the embodiments described in this specification and the configurations described in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0073] Additionally, throughout the specification, whenever a part is said to “include,” “comprise,” “have,” or “have” a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0074] In addition, the terms 'about', 'substantially', etc. used throughout this specification are used in the sense of or near to the numerical values ​​when manufacturing and material tolerances inherent to the meanings stated are presented, and are used to prevent unscrupulous infringers from unfairly exploiting the disclosure where exact or absolute values ​​are mentioned to aid understanding of this specification.

[0075] In this specification, terms such as "upper," "lower," "left," "right," "inner," and "outer" refer to positions or directions within the referenced drawings and should not be limiting. The terms "inner" and "outer" refer to directions toward or away from the geometric center of the designated device, system, or its components, respectively. These terms include the words listed above, their derivatives, and words of similar meaning.

[0076] In this specification, when it is said that a member is located “on” another member, this includes not only cases where a member is in contact with another member, but also cases where another member exists between the two members.

[0077] The above-described objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily practice the technical idea of ​​the present invention. In describing the present invention, if it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the gist of the present invention, a detailed description thereof will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0078] Although terms like "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, a "first" component may also be a "second" component.

[0079] Throughout the specification, unless otherwise specifically stated, each element may be singular or plural.

[0080] Hereinafter, the phrase "any configuration is placed on (or below)" a component or "on (or below)" a component may mean that any configuration is placed in contact with the upper surface (or lower surface) of said component, and that other configurations may be interposed between said component and any configuration placed on (or below) said component.

[0081] Additionally, when it is described that a component is "connected," "coupled," or "contacted" with another component, it should be understood that the components may be directly connected or in contact with each other, but that other components may also be "interposed" between the components, or that each component may be "connected," "coupled," or "contacted" through another component.

[0082] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not necessarily be construed to include all of the components or steps described in the specification, and should be construed to mean that some of the components or steps may not be included, or that additional components or steps may be included.

[0083] Throughout the specification, when we refer to "A and / or B", this means A, B, or A and B, unless otherwise stated, and when we refer to "C to D", this means C or more and D or less, unless otherwise stated.

[0084] In describing the embodiment, the axial direction refers to the direction in which the axis forming the winding center of the jelly-roll type electrode assembly extends, the radial direction refers to the direction closer to or farther from the axis, and the circumferential direction refers to the direction surrounding the axis.

[0085]

[0086] Referring to FIGS. 2 to 8b, a battery cell according to an embodiment of the present invention may include an electrode assembly (20), a current collector (30, 40) electrically connected to the electrode assembly (20), and a can (10) that accommodates the electrode assembly (20) and the current collector (30, 40). The battery cell may be a cylindrical battery cell.

[0087] The above electrode assembly (20) may be a cylindrical shape manufactured by preparing a first electrode (21), a second electrode (22), and a separator (28) extending in the longitudinal direction with a predetermined width as shown in FIG. 2, forming a laminate by stacking the first electrode (21), the separator (28), the second electrode (22), and the separator (28) in that order as shown in FIG. 3, and then winding this around a core shaft as shown in FIG. 4.

[0088] The above first electrode (21) may be an anode, and the above second electrode (22) may be a cathode. Of course, the opposite may also be the case.

[0089] The first electrode (21) and the second electrode (22) can be manufactured in the form of sheets. The electrode sheet can be manufactured in the form of an active material layer (24) applied to the surface of a metal foil (23). The electrode sheet can have a holding portion (25) region where the active material layer (24) is applied, and a non-coated portion (26) region where the active material layer (24) is not applied. The positive electrode sheet can have a non-coated portion (26) region on one side in the width direction, and the negative electrode sheet can have a non-coated portion (26) region on the other side in the width direction.

[0090] The above-mentioned non-conductive portion (26) area may be exposed or protruded in the width direction of the laminate. The non-conductive portion (26) itself may function as an electrode tab (27). Of course, a separate electrode tab (27) may be connected to the non-conductive portion (26).

[0091] In the above-mentioned blank portion (26), notches can be formed at a predetermined interval to form flag-shaped notching tabs (27).

[0092] In FIGS. 2 and 3, it is exemplified that the notching tabs (27) are in the shape of an equilateral trapezoid. However, their shapes may be various, such as a semicircle, a semi-ellipse, a triangle, a rectangle, a parallelogram, etc.

[0093] In FIGS. 2 and 3, the notching tabs (27) arranged along the longitudinal direction are exemplified as having the same width. However, the width of the notching tabs may also be gradually or stepwise widened from the core side to the outer periphery side.

[0094] In FIGS. 2 and 3, the height of the notching tabs (27) gradually increases from the core side to the outer circumference side. However, the height of these notching tabs may be implemented in a constant or gradually decreasing form.

[0095] In FIGS. 2 and 3, a structure in which a notching tab (27) is deleted from a predetermined section of the centripetal end of the above-mentioned plain portion (26) and a predetermined section of the centrifugal end is exemplified. However, it is of course possible that the notching tab is not deleted from the centripetal end of the plain portion, and that the notching tab is not deleted from the centrifugal end of the plain portion.

[0096] Referring to Fig. 4, in the jelly roll-shaped electrode assembly (20), the notched tab (27) can be bent radially and flattened. The notched tab (27) can be bent radially inward or outward. In Fig. 4, a structure in which the notched tab (27) is bent radially inward is exemplified.

[0097] The above-mentioned notched tabs (27) can be bent one by one during the process of forming a jelly roll-shaped electrode assembly (20) by winding the laminate. Alternatively, the above-mentioned notched tabs (27) can be bent all at once after the laminate is wound to form a jelly roll-shaped electrode assembly.

[0098] The notching tabs (27) of the first electrode (21) and the notching tabs (27) of the second electrode (22), which are bent and overlapped in the radial direction in this way, can provide a first plane and a second plane that are substantially perpendicular to the axial direction at the axial ends of the electrode assembly (20), respectively.

[0099] The first and second surfaces, which are substantially flat and provided by bending the notched tabs (27) exposed at both axial ends of the electrode assembly (20), can be joined with the first collector plate (30) and the second collector plate (40), as shown in FIGS. 5 and 6.

[0100] In FIGS. 5 and 6, the first collector plate (30) is exemplified as a positive collector plate and the second collector plate (40) is a negative collector plate. However, the first collector plate (30) may be a negative collector plate and the second collector plate (40) may be a positive collector plate.

[0101] The second collector plate (40) may include a copper material, and the first collector plate (30) may include an aluminum material. However, the materials are not limited thereto and may include any material commonly used in the art.

[0102] The above-mentioned collector plate (30, 40) can be manufactured by punching, trimming, piercing, and bending a metal sheet.

[0103] Referring to FIG. 5, the first collector plate (30) may include a first electrode connection portion (31) and a first terminal connection portion (32). The first electrode connection portion (31) may define a hole corresponding to the core hollow portion (29) of the electrode assembly (20) and may be formed to surround the hole. The first electrode connection portion (31) does not need to be in a closed loop shape and may be formed in a C shape as illustrated. That is, the first electrode connection portion (31) may extend in the circumferential direction. The first electrode connection portion (31) may be connected to the electrode tab. The first terminal connection portion (32) may be formed to be connected to the first electrode connection portion (31) and to be elongated and have a predetermined width so as to be flexibly deformed in the axial direction from the first electrode connection portion (31). A first electrode terminal (17), which will be described later, can be connected to the tip of the first terminal connection portion (32).

[0104] Referring to FIG. 6, the second collector plate (40) may be provided with a second terminal connection portion (42) extending radially from the center, and a second electrode connection portion (41) connected to the second terminal connection portion (42) through a ring portion that connects the centrifugal edge of the second terminal connection portion (42) in the circumferential direction. The second electrode connection portion (41) may be arranged alternately with the second terminal connection portion (42) along the circumferential direction, and may extend radially inward from the ring portion. The radially inner end of the second electrode connection portion (41) may not be connected to the second terminal connection portion (42). The center portion of the second terminal connection portion (42) may cover at least a portion of the core hollow portion (29) of the electrode assembly (20). The second electrode connection portion (41) may be connected to an electrode tab.

[0105] The above first electrode connection portion (31) can be joined to the notched tab (27) of the first electrode (21) of the electrode assembly (20) by laser welding or the like before the electrode assembly (20) is placed in the can. The welding line of the laser can extend radially.

[0106] The second electrode connection portion (41) may be joined to the notched tab (27) of the second electrode (22) of the electrode assembly (20) by laser welding or the like before the electrode assembly (20) is placed in the can. The welding line of the laser may extend radially.

[0107] Of course, in contrast, the first electrode connection portion (31) may be joined to the notched tab (27) of the first electrode (21) of the electrode assembly (20) by laser welding or the like after the electrode assembly (20) is placed in the can (10). Accordingly, the welding of the second collector plate (40) and the bottom member (12) can be performed more smoothly.

[0108] In addition, the first electrode connection portion (31) may be joined to the notched tab (27) of the first electrode (21) of the electrode assembly (20) by a method such as laser welding before injecting the electrolyte into the can (10) after welding the second collector plate (40) and the bottom member (12).

[0109]

[0110] Referring to FIG. 7, the electrode assembly (20) can be electrically connected to the cap (16).

[0111] The cap (16) may include a cap body (160) having a hole formed in the center thereof and an edge portion (166) connected to the radially outer side of the cap body. A rivet terminal (17) may be riveted to the cap body (160). In addition, the rivet terminal (17) and the cap body (160) surrounding the rivet terminal may function as a first electrode terminal (17) and a second electrode terminal, respectively.

[0112] For example, the first electrode terminal (17) of the cap (16) can be fixed and electrically connected by being joined to the end of the first terminal connection portion (32) of the first collector plate (30) by a thermal bonding method such as welding.

[0113] The electrode assembly (20) may be connected to the cap (16) before being placed in the can. Of course, the electrode assembly (20) may also be connected to the cap (16) after being placed in the can.

[0114]

[0115] This is described in more detail with reference to FIGS. 8a and 8b.

[0116] The can (10) may include a side wall member (11) extending axially between a first end and a second end, and a bottom member (12) connected to the second end of the side wall member (11) and extending radially. The first end of the side wall member (11) may be open to define an opening of the can (10).

[0117] The above-mentioned bottom member (12) may have a disc shape, and the side wall member (11) may have a circular tubular shape. The side wall member (11) may not have a separate beading portion formed thereon. That is, the side wall member (11) may have a columnar shape with a circular or oval cross-section. If the side wall member (11) does not have a beading portion formed thereon, the distance between the cap (16) and the electrode assembly (20) can be shortened, thereby further improving the energy density of the battery cell.

[0118] The above-mentioned bottom member (12) and side wall member (11) can be manufactured by forming a metal sheet having a nickel plated surface on steel using a deep drawing process, and trimming the front end of the side wall member (11) with a punch while holding it with a blank holder. Of course, the material of the can (10) is not limited thereto. The bottom member (12) can have a uniform thickness. Accordingly, heat can be uniformly discharged through the bottom member (12). Since the bottom member (12) does not include a separate vent notch and can have a uniform thickness, a cooling structure can be implemented on the lower side of the bottom member (12).

[0119] The above opening accommodates the electrode assembly (20) in the can (10) and can be sealed by covering it with a cap (16).

[0120] The cap (16) may include a cap body (160) having a hole formed in the center thereof, and an edge portion (166) connected to the radially outer side of the cap body (160). The cap (16) may include at least one vent notch (163). The cap body (160) and / or the edge portion (166) may include a vent notch (163) whose strength is weakened by making the cap thinner. Accordingly, when the internal pressure of the battery cell increases, the vent notch (163) is broken, opening the cap body (160) and / or the edge portion (166), thereby preventing an explosion of the battery cell. One or more vent notches (163) may be formed. The cap body (160) and the edge portion (166) may be interconnected through the vent notch (163) interposed therebetween in the radial direction. The above cap (16) may be in the form of a plate including a cap body (160) and an edge portion (166).

[0121] In the conventional cap (the cap has a sloped portion positioned between the cap body portion and the edge portion, so that the cap body portion protrudes outward compared to the edge portion. However, in the cap of the present invention, since a separate sloped portion is not formed between the cap body and the edge portion, the cap body does not protrude outward. Accordingly, unnecessary empty space is not formed between the cap and the electrode assembly, so that the energy density of the battery cell can be improved.

[0122] A first electrode terminal (17) can be fitted into a hole formed in the center of the cap (16). The first electrode terminal (17) can be fixed by riveting to the cap body (160) with a terminal gasket (18) interposed therebetween. The terminal gasket (18) is interposed between the first electrode terminal (17) and the cap body (160), sealing the inside and the outside with the cap (16) as the boundary, preventing leakage of the electrolyte, and electrically insulating the first electrode terminal (17) and the cap (16).

[0123] However, the method of connecting the first electrode terminal (17) and the cap (16) is not limited to this. For example, if there is a structure that can seal between the first electrode terminal (17) and the cap (16) and electrically insulate the first electrode terminal (17) and the cap (16), various other fixing methods, such as a bolt-nut joint method, a glass seal method, or a chrome coating & PP-MAH thermal bonding method, can also be applied.

[0124] The first electrode terminal (17) may have a first polarity, and the cap (16) may have a second polarity. The edge portion (166) of the cap (16) may be fixed to the first end portion of the side wall member (11) of the can (10) and may be electrically connected thereto. Accordingly, the cap (16), the side wall member (11) of the can (10), and the bottom member (12) connected thereto may all have a second polarity.

[0125] Accordingly, the battery cell in which the cap (16) is arranged may have both the first electrode terminal (17) and the second electrode terminal (14) arranged on the opening side of the can (10). In addition, the bus bar connected to the first electrode terminal (17) of the battery cell and the bus bar connected to the second electrode terminal (14) may both be positioned on the upper side of the battery cell. Accordingly, the battery cell may be provided with a cooling structure for cooling the battery cell on the bottom member (12) side of the can (10).

[0126] In one example, the first electrode terminal (17) may be a positive terminal and the second electrode terminal (14) may be a negative terminal. Of course, the opposite may also be true.

[0127] .

[0128] As illustrated in FIG. 8a, the electrode assembly (20) can be accommodated in the can (10) in a state where the second collector plate (40) is aligned so as to face the bottom member (12) of the can (10). Accordingly, both surfaces of the flat second collector plate (40) can be interposed between the bottom member (12) and the second surface of the second electrode (22), respectively. The second collector plate (40) can be in surface contact with the second surface of the second electrode (22) and also in surface contact with the bottom member (12). That is, one surface of the second collector plate (40) can be in surface contact with the electrode assembly (20), and the other surface of the second collector plate (40) can be in surface contact with the bottom member (12). More specifically, the second electrode connection portion (41) on one surface of the second current collector plate (40) may be in contact with the electrode tab of the electrode assembly (20), and the second terminal connection portion (42) on the other surface of the second current collector plate (40) may be in contact with the bottom member (12). Accordingly, the electrode assembly (20) may have the first electrode disposed on the opening side, and the second electrode disposed on the bottom member side. In addition, the surface of the electrode assembly (20) facing the bottom member (12) may be supported by the bottom member (12). Since the electrode assembly (20) is supported by the bottom member (12) through the second collector plate (40), no separate insulating layer, such as an air insulating layer, exists between the electrode assembly (20) and the bottom member (12), so that the heat inside the battery cell can be smoothly discharged to the outside through the bottom member (12).

[0129] The second terminal connection portion (42) of the second collector plate (40) can be joined to the bottom member of the can (10). The joining may be thermal joining. The thermal joining may be, for example, welding.

[0130] When the electrode assembly (20) is accommodated inside the can (10), it includes an electrode tab electrically connected to the first electrode, and the electrode tab can be connected to the first electrode terminal (17). The electrode tab of the first electrode and the first collector plate (30) can be arranged to face the opening of the can (10). The electrode tab can be directly connected to the first electrode terminal (17), but can also be connected through the first collector plate (30). The first terminal connection portion (32) of the first collector plate (30) can be extended thinly and long to provide flexibility during the assembly process of the cap (16).

[0131] Before covering the opening with the cap (16), an electrolyte may be injected into the interior of the can (10). After injecting the electrolyte, the opening may be covered with the cap (16).

[0132] The edge portion (166) of the cap (16) may be electrically connected by welding to the axial first end portion of the side wall member (11). For example, as shown in FIG. 8a, the end portion of the edge portion (166) of the cap (16) may be connected to the inner surface of the first end portion of the side wall member (11). Alternatively, as shown in FIG. 8b, the first end portion of the side wall member (11) may be connected to the lower surface of the edge portion (166) of the cap (16).

[0133] The above edge portion (166) and the side wall member (11) can be connected through welding. For example, a weld (W) can be formed at the abutment portion of the side wall member (11) and the cap (16) through seam welding in which a laser is irradiated along the circumferential direction to the abutment portion of the side wall member (11) and the cap (16). By the weld (W), the cap (16) and the side wall member (11) can be sealed and electrically connected.

[0134] An insulator (19) made of an electrically insulating material may be interposed between the cap (16) and the electrode assembly (20). When the cap (16) is fixed to the side wall member (11), the cap (16) can axially support the insulator (19). Accordingly, due to the elasticity of the insulator (19), the second collector plate (40) can be elastically pressed in the axial direction between the electrode assembly (20) and the bottom member (12).

[0135] For example, the upper surface of the insulator (19) can support the cap (16), and the lower surface of the insulator (19) can support the electrode assembly (20). That is, the insulator (19) is positioned between the cap (16) and the electrode assembly (20), so that the can (10) and the electrode assembly (20) can be more closely attached. The insulator (19) is positioned on the upper side of the electrode assembly (20), can be in contact with the electrode assembly (20), can be in contact with the first collector plate (30), and can be in contact with the electrode assembly (20) and the first collector plate (30) at the same time.

[0136] Since conventional cans have beaded portions on the sidewalls, the insulator had to be interposed with the beaded portion in mind. For example, it was necessary to consider the extent to which the beaded portion was inserted into the can. However, since the can of the present invention does not have a separate beaded portion on the sidewalls, the insulator design is easier, and the insulator can be more firmly attached to the electrode assembly and cap.

[0137]

[0138] Referring to Fig. 9, the battery cell (72) may be accommodated in a pack housing (71) of a battery pack (70). The battery pack (70) may be configured using a battery module, which is an intermediate form of assembly, or the battery pack (70) may be configured directly without a battery module, as shown.

[0139] Since the battery cell (72) described above has a large volume in itself, there is no particular difficulty in implementing a battery pack (70) even without using an intermediate structure called a battery module. Furthermore, the battery cell (72) has low internal resistance and a higher energy density. Accordingly, the energy density of a battery pack (70) equipped with the battery cell (72) can be implemented even higher.

[0140] A battery pack (70) with such a high energy density can store the same amount of energy while reducing its volume and weight. Therefore, when a battery pack (70) equipped with such battery cells (72) is installed in a vehicle, such as an automobile (80) that uses electricity as its energy source, as illustrated in FIG. 10, the vehicle's mileage relative to its energy consumption can be further increased.

[0141] Even if the above battery cell (72) generates heat in the electrode assembly, this heat can be quickly dissipated downwards through the second electrode, the second collector plate, and the bottom member of the can. Accordingly, if a cooling structure is implemented in the bottom of the battery pack (70), the cooling of the battery cell (72) can be achieved very smoothly.

[0142]

[0143] It should be understood that the above-described embodiments are illustrative in all respects and not restrictive, and the scope of the present invention will be determined by the claims that follow, rather than by the detailed description set forth above. Furthermore, the meaning and scope of the claims that follow, as well as all possible modifications and variations derived from their equivalent concepts, should be construed as encompassing the scope of the present invention.

[0144] Although the present invention has been described with reference to the drawings exemplified above, it is to be understood that the present invention is not limited to the embodiments and drawings disclosed herein, and that various modifications may be made by those skilled in the art within the scope of the technical idea of ​​the present invention. Furthermore, even if the operational effects according to the configuration of the present invention have not been explicitly described while describing the embodiments of the present invention, it is natural that the effects predictable by the corresponding configuration should also be acknowledged.

[0145] [Explanation of symbols]

[0146] 10: Can

[0147] 11: Side wall member

[0148] 12: Flooring

[0149] 14: Second electrode terminal

[0150] 15: Cap gasket

[0151] 16: Cap

[0152] 160: Cap body

[0153] 161: Hall

[0154] 163: Vent notch

[0155] 166: Edge

[0156] 17: First electrode terminal

[0157] 18: Terminal gasket

[0158] W: Welding

[0159] 19: Insulator

[0160] 20: Electrode assembly

[0161] 21: First electrode

[0162] 22: Second electrode

[0163] 23: Metal foil

[0164] 24: Active material layer

[0165] 25: Maintenance Department

[0166] 26: Ministry of Immigration

[0167] 27: Electrode tab (notching tab)

[0168] 28: Membrane

[0169] 29: Hollow core

[0170] 30: First Collection Edition

[0171] 31: First electrode connection

[0172] 32: First terminal connection

[0173] 40: Second Collection Edition

[0174] 41: Second electrode connection

[0175] 42: Second terminal connection

[0176] 70: Battery pack

[0177] 71: Pack Case

[0178] 72: Battery cell

[0179] 80: Car

Claims

1. A can having a side wall member extending in the axial direction, an opening provided at the first end of the side wall member, and a bottom member connected to the second end of the side wall member; An electrode assembly having a first electrode and a second electrode and accommodated in the can; A cap covering the opening of the can and electrically connected to the first end of the side wall member; A first electrode terminal is installed in the central portion of the cap and is electrically insulated from the cap; A battery cell, wherein the first electrode is electrically connected to the first electrode terminal, and the second electrode is electrically connected to the can and the cap.

2. In claim 1, The above electrode assembly is a battery cell, wherein the surface facing the bottom member is supported by the bottom member.

3. In claim 1, A battery cell, wherein the first electrode is disposed on the opening side and the second electrode is disposed on the bottom member side.

4. In claim 1, A battery cell in which there is no separate insulating layer between the electrode assembly and the bottom member.

5. In claim 1, Including an electrode tab electrically connected to the first electrode, A battery cell, wherein the electrode tab electrically connected to the first electrode is connected to the first electrode terminal.

6. In claim 1, Including an electrode tab electrically connected to the second electrode, A battery cell, wherein the electrode tab electrically connected to the second electrode is positioned at the lower portion of the electrode assembly and is bonded to the bottom member.

7. In claim 1, The first electrode is electrically connected to the first electrode terminal through the first collector plate, The above first collector plate has a first electrode connecting portion connected to the first electrode, and a first terminal connecting portion connected to the first electrode terminal. The first electrode protrudes axially outward from the axial first end of the electrode assembly and is bent radially, thereby providing a first surface facing axially outward, A battery cell in which the first electrode connecting portion of the first collector plate is bonded to the first surface and electrically connected.

8. In claim 1, The second electrode is electrically connected to the floor member through the second collector plate, The second collector plate has a second electrode connection portion connected to the second electrode and a second terminal connection portion connected to the bottom member of the can. The second electrode protrudes axially outward from the axial second end of the electrode assembly and is bent radially to provide a second surface whose surface faces axially outward, A battery cell in which the second electrode connecting portion of the second collector plate is bonded to the second surface and electrically connected.

9. In claim 1, The above cap includes a central portion and an edge portion, A battery cell in which the edge portion is electrically connected to the first end of the side wall member.

10. In claim 9, A battery cell, wherein the end of the edge portion is joined to the inner surface of the first end of the side wall member.

11. In claim 9, A battery cell, wherein the first end of the side wall member is joined to the lower surface of the edge portion.

12. In claim 1, A battery cell, wherein the cap includes at least one vent notch.

13. In claim 1, An electrically insulating insulator is positioned between the cap and the electrode assembly, The upper surface of the above insulator supports the cap, The lower surface of the above insulator supports the above electrode assembly, a battery cell.

14. A battery pack comprising a battery cell according to any one of claims 1 to 13 and a pack case containing the battery cell.

15. In claim 14, A battery pack wherein the battery cell is built into the pack case such that the bottom member is in contact with the bottom of the pack case and the cap faces upward.

16. In claim 13, A battery pack, wherein a cooling structure for cooling the battery cell through the bottom member of the battery cell is provided on the bottom of the pack case.

17. A vehicle equipped with a battery pack according to any one of claims 14 to 16 and driven by power from the battery pack.

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