Battery cell, battery pack including the battery cell, and automobile

Abstract

A battery cell according to one embodiment of the present invention includes an electrode assembly, a housing that accommodates the electrode assembly through an opening provided on one side and has a closed portion formed on the opposite side of the opening, a current collector disposed between the electrode assembly and the closed portion and electrically coupled to the electrode assembly, a terminal electrically coupled to the electrode assembly through the closed portion, and a CID interposed between the terminal and the current collector and coupled to the current collector with a greater coupling force than the terminal.

Description

Technical Field

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

[0002] This application claims priority based on Korean Patent Application No. 10-2023-0077099 filed on June 15, 2023, and all the contents disclosed in the specification and drawings of the application are incorporated into this application.

Background Art

[0003] Currently, as fuse devices used in secondary batteries, there are PTC thermistors (Positive Temperature Coefficient thermistors), TCOs (thermal cut-outs), and the like. However, PTC thermistors and TCOs have the disadvantage that their own resistance increases as they operate repeatedly, increasing the overall resistance in the circuit.

[0004] Also, all of the above elements operate by heat generation due to overcurrent. That is, the above elements are elements that operate to cut off the current flow only when an overcurrent occurs in the circuit current path due to overcharging or the like and the temperature rises accordingly.

[0005] Therefore, in the case of the above elements, they operate to cut off the overcurrent only after the safety has already been threatened by heat generation, and do not cut off the overcurrent immediately when the cause of the temperature rise occurs. Thus, if the overcurrent is not cut off at an appropriate timing even when the internal pressure of the secondary battery increases due to an abnormal rise in the internal temperature or the like, there is a risk of safety problems such as ignition and explosion.

[0006] Furthermore, the aforementioned elements operate simply in response to temperature, making them unsuitable for use in high-power secondary batteries such as those used in automobile battery packs. In other words, automobile battery packs require a high C-rate, which in turn generates a lot of heat. However, elements such as PTC thermistors, TCOs, and thermal fuses have the problem of activating excessively prematurely when exposed to high-temperature environments.

[0007] Therefore, there is a need for a secondary battery that can not only be used in environments where high currents flow, but also has a structure that can preemptively cut off the current when an event causing a temperature rise (for example, an increase in the internal pressure of the secondary battery) occurs, before the temperature rises to a level where safety problems may arise. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The present invention was conceived in view of the above-mentioned problems, and aims to provide a battery cell having a structure that can quickly interrupt the current when an abnormality occurs in the battery cell, a battery pack including the battery cell, and an automobile.

[0009] The technical problems that this invention aims to solve are not limited to those described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention that follows. [Means for solving the problem]

[0010] A battery cell according to one aspect of the present invention for solving the above-mentioned problems includes an electrode assembly, a housing comprising an open portion provided on one side and a closed portion formed on the opposite side of the open portion, and housing the electrode assembly through the open portion, a current collector disposed between the electrode assembly and the closed portion and electrically coupled to the electrode assembly, a terminal electrically coupled to the electrode assembly through the closed portion, and a CID (Current Interruption Device) interposed between the terminal and the current collector and coupled to the current collector with a greater coupling force than the terminal.

[0011] The area of ​​the coupling surface between the CID and the current collector may be even larger than the area of ​​the coupling surface between the CID and the terminal.

[0012] The coupling surface formed at the lower end of the terminal may be provided at a position corresponding to the winding center hole of the electrode assembly.

[0013] The CID can be coupled to the current collector both inside and outside the region corresponding to the winding center hole.

[0014] The current collector may include a first coupling portion electrically coupled to the electrode assembly, and a second coupling portion located radially along the electrode assembly, spaced apart from the first coupling portion, and provided at a position corresponding to the winding center hole of the electrode assembly.

[0015] The CID can be coupled to both the first and second coupling portions.

[0016] The CID may be configured to cover both the first and second bonding portions along the radial direction of the electrode assembly.

[0017] The battery cell may include a CID gasket interposed between the closing portion and the current collector, which maintains the separated state when separation occurs between the closing portion and the current collector due to an increase in the internal pressure of the housing.

[0018] The CID gasket may be configured to have an elastic restoring force in a direction of expansion between the closing portion and the current collector.

[0019] The CID gasket may be configured to expand due to an increase in the internal temperature of the housing.

[0020] At least a part of the CID gasket may be interposed between the CID and the closing portion.

[0021] The battery cell may include a battery cap configured to cover the open portion.

[0022] The battery cap may include a vent portion configured to be more fragile than the surroundings.

[0023] A coupling portion between the terminal and the CID may be configured to break at a pressure lower than the vent pressure of the vent portion.

[0024] A battery pack according to another aspect of the present invention for solving the above-described problems includes a battery cell according to an aspect of the present invention.

[0025] An automobile according to still another aspect of the present invention for solving the above-described problems includes a battery pack according to an aspect of the present invention.

Advantages of the Invention

[0026] According to an aspect of the present invention, when an abnormality occurs in a battery cell, the current can be quickly interrupted, thereby ensuring the safety in the use of the secondary battery.

[0027] Also, according to an aspect of the present invention, it is possible to prevent a phenomenon in which an electrical connection is made again after the current is interrupted due to an abnormality in the battery cell.

[0028] Also, according to one aspect of the present invention, the current can be cut off in advance before the vent of the battery cell occurs, thereby further improving the safety in the use of the secondary battery.

[0029] However, the advantageous effects derived through the present invention are not limited to the effects described above, and other advantageous effects not mentioned will be clearly understood by those skilled in the art from the description of the invention to be described later.

[0030] The following drawings attached to this specification illustrate preferred embodiments of the present invention and are for the purpose of further understanding the technical idea of the present invention together with the detailed description of the invention. Therefore, the present invention is not to be construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0031] [Figure 1] It is a partial cross-sectional view showing the upper structure of a battery cell according to an embodiment of the present invention. [Figure 2] It is a diagram for explaining the breakage of the coupling part between components due to the increase in the internal pressure of the battery cell shown in FIG. 1. [Figure 3] In the battery cells shown in FIGS. 1 and 2, it is a diagram for explaining the phenomenon that when the CID of an embodiment of the present invention is omitted, the coupling part between the terminal and the current collector moves together without breaking due to the rise of the terminal. [Figure 4] In the battery cells shown in FIGS. 1 and 2, it is a diagram for explaining the phenomenon that when the CID of an embodiment of the present invention is applied, the coupling part between the terminal and the CID breaks due to the rise of the terminal. [Figure 5] It is a diagram showing a battery cell to which a current collector having a different form from the current collector shown in FIG. 1 is applied. [Figure 6] It is a diagram for explaining the breakage of the coupling part between components due to the increase in the internal pressure of the battery cell shown in FIG. 5. [Figure 7] It is a diagram showing an exemplary form of the current collector applied to the battery cells shown in FIGS. 5 and 6. [Figure 8] Figures 5 and 6 show exemplary configurations of current collectors applied to the battery cells shown. [Figure 9] Figures 5 and 6 illustrate the phenomenon in which, when the CID of one embodiment of the battery cell is omitted, the connection between the terminal and the current collector moves together without breaking due to the upward movement of the terminal. [Figure 10] Figures 5 and 6 illustrate the phenomenon in which, in a battery cell shown in Figure 5 and 6, when the CID of one embodiment of the present invention is coupled only to the second coupling portion of the current collector, the coupling portion between the terminal and the CID moves together without breaking due to the upward movement of the terminal. [Figure 11] Figures 5 and 6 illustrate the phenomenon in which the connection between the terminal and the CID breaks due to the upward movement of the terminal when the CID of one embodiment of the present invention is fully connected to the first and second coupling portions of the current collector in the battery cell shown in Figures 5 and 6. [Figure 12] Figure 5 shows a battery cell to which a CID gasket has been further applied. [Figure 13] Figure 12 illustrates the fracture of joints between components due to increased internal pressure in the battery cell. [Figure 14] This figure shows a battery cell with a structure in which the CID gasket is positioned differently compared to the battery cell shown in Figure 12. [Figure 15] This figure shows a battery cell with a structure in which the CID gasket is positioned differently compared to the battery cell shown in Figure 12. [Figure 16] This figure shows the external appearance of a battery cell according to one embodiment of the present invention. [Figure 17] Figure 16 is a diagram showing the overall internal structure of the battery cell. [Figure 18] This is a partial cross-sectional view showing the lower structure of a battery cell according to one embodiment of the present invention. [Figure 19]This figure shows a battery pack according to one embodiment of the present invention. [Figure 20] This diagram shows an automobile based on one embodiment of the present invention. [Modes for carrying out the invention]

[0032] Preferred embodiments of the present invention will now be described in detail with reference to the attached drawings. Prior to this, terms and words used herein and in the claims shall not be interpreted in their usual and dictionary sense, but in accordance with the principle that the inventor himself may appropriately define the concepts of terms in order to best describe the invention, and shall be interpreted in a sense and concept corresponding to the technical idea of ​​the present invention. Accordingly, the embodiments described herein and the configurations shown in the drawings represent only one of the most preferred embodiments of the present invention and do not represent the entire technical idea of ​​the present invention, and it should be understood that there may be a variety of equivalents and modifications that can be substituted therein at the time of this application.

[0033] A battery cell 1 according to one embodiment of the present invention will be described with reference to Figures 1 to 4. Figure 1 is a partial cross-sectional view showing the upper structure of a battery cell according to one embodiment of the present invention, and Figure 2 is a diagram illustrating the fracture of the joint between components due to the increase in internal pressure of the battery cell shown in Figure 1. Figure 3 is a diagram illustrating the phenomenon in which, in the battery cell shown in Figures 1 and 2, when the CID of one embodiment of the present invention is omitted, the joint between the terminal and the current collector moves together without fracture due to the rising of the terminal. Furthermore, Figure 4 is a diagram illustrating the phenomenon in which, in the battery cell shown in Figures 1 and 2, when the CID of one embodiment of the present invention is applied, the joint between the terminal and the CID fractures due to the rising of the terminal.

[0034] First, referring to Figure 1, a battery cell 1 according to one embodiment of the present invention includes an electrode assembly 10, a housing 20, a current collector (first current collector) 30, terminals 40, and a CID (Current Interruption Device) 50.

[0035] The electrode assembly 10 may include a first electrode, a second electrode, and a separation membrane interposed between the first and second electrodes. The electrode assembly 10 may be, for example, a jelly-roll type electrode assembly in which a laminate including the first electrode, the second electrode, and the separation membrane is wound in one direction. The electrode assembly 10 may have a first blank portion 11 at its upper end. The first blank portion 11 means a region on the first electrode that is not coated with electrode active material. The first blank portion 11 may be formed at one end of the first electrode and may extend along the winding direction of the electrode assembly 10. The first blank portion 11 may extend upward along the height direction (parallel to the Z-axis) of the electrode assembly 10.

[0036] The housing 20 may be configured to accommodate the electrode assembly 10 through an opening provided on one side. The housing 20 may also have a closed portion formed on the opposite side of the opening.

[0037] The current collector 30 may be positioned between the electrode assembly 10 and the closing portion of the housing 20. The current collector 30 may be electrically coupled to the electrode assembly 10. For example, one surface of the current collector 30 may be coupled to a first blank portion 11 provided at the upper end of the electrode assembly 10. The coupling between the current collector 30 and the electrode assembly 10 may be performed, for example, by laser welding, ultrasonic welding, or the like.

[0038] On the other hand, the first blank portion 11 may comprise a plurality of segmented sections formed by dividing along the winding direction of the electrode assembly 10, and such segmented sections may be bent toward the core of the electrode assembly 10, for example. The bent segmented sections of the first blank portion 11 may overlap each other to form multiple layers. When the segmented sections of the first blank portion 11 are bent in this manner, the current collector 30 may be bonded to a substantially flat surface formed by the bending of the first blank portion 11.

[0039] The terminal 40 can be electrically coupled to the electrode assembly 10 through the closure of the housing 20. The terminal 40 can, for example, penetrate approximately the center of the closure of the housing 20. The terminal 40 can be fixed, for example, to the inner surface of the closure of the housing 20 by riveting.

[0040] The CID 50 may be interposed between the terminal 40 and the current collector 30. The CID 50 may be a plate containing a conductive metal. The first surface of the CID 50 may be coupled to the terminal 40, and the second surface, which is the opposite surface of the first surface, may be coupled to the current collector 30. The CID 50 may be coupled to the current collector 30 with a greater coupling force than the coupling force between the terminal 40. That is, the coupling force between the second surface of the CID 50 and the current collector 30 may be formed to be even stronger than the coupling force between the first surface of the CID 50 and the terminal 40.

[0041] Referring to Figure 2, by configuring the coupling force between components using CID 50 in this way, when the housing 20 expands due to an increase in the internal pressure of the battery cell 1, the coupling portion between the terminal 40 and the CID 50 breaks quickly, thereby interrupting the flow of current through the terminal 40.

[0042] Referring to Figure 3, unlike the battery cell 1 of one embodiment of the present invention, in the case of a battery cell 1 to which CID 50 is not applied, when the terminal 40 rises due to an increase in internal pressure, a phenomenon may occur in which the connection between the current collector 30 and the electrode assembly 10 partially breaks first before the connection between the current collector 30 and the terminal 40 breaks, and / or a phenomenon may occur in which the breakage of the connection between the current collector 30 and the terminal 40 is delayed as the current collector 30 bends.

[0043] The differences in bonding strength described above can occur, for example, due to differences in bonding area. For instance, the bonding surface area between the CID 50 and the current collector 30 can be made larger than the bonding surface area between the CID 50 and the terminal 40.

[0044] After welding the CID 50 to the current collector 30 coupled to the electrode assembly 10, the assembly including the electrode assembly 10, current collector 30, and CID 50 is pushed in through the opening of the housing 20, bringing the CID 50 into contact with the bottom surface of the terminal 40. Next, the current collector 30, CID 50, and terminal 40 are welded together by inserting a welding device through the winding center hole 10a formed approximately in the center of the electrode assembly 10 or by irradiating it with a laser. At this time, by configuring the welding area between the CID 50 and the terminal 40 to be smaller than the welding area between the current collector 30 and the CID 50, the welded portion between the terminal 40 and the CID 50 can be rapidly fractured due to the rise in internal pressure.

[0045] The coupling surface formed at the lower end of the terminal 40 may be provided at a position corresponding to the winding center hole 10a of the electrode assembly 10. In this case, the current collector 30 is not coupled to the electrode assembly 10 at the position corresponding to the coupling portion between the CID 50 and the terminal 40. As a result, when the internal pressure of the battery cell 1 increases, causing the closure portion to warp, and the terminal 40 rises as a result, warping may occur in the region of the current collector 30 corresponding to the winding center hole 10a. Such warping of the current collector 30 can hinder the fracture of the coupling portion between the terminal 40 and the CID 50. If the CID 50 of one embodiment of the present invention is applied, the CID 50 reinforces the rigidity of the current collector 30, allowing the fracture of the coupling portion between the terminal 40 and the CID 50 to occur more quickly.

[0046] Referring to Figure 4 in conjunction with Figures 1 to 3, the CID 50 can be coupled to the current collector 30 in the inner (region B) and outer (region A) areas corresponding to the winding central hole 10a. In this case, the warping of the current collector 30 and the CID 50 can be further suppressed, thereby causing the coupling portion between the terminal 40 and the CID 50 to break more quickly.

[0047] On the other hand, referring to Figures 1 and 2, the battery cell 1 of one embodiment of the present invention may include an insulator IS and / or an insulating gasket G1. The insulator IS may be placed in the space formed between the closing portion of the housing 20 and the current collector 30. The insulator IS may include an insulating material. The insulator IS can prevent contact between the current collector 30 and the housing 20, which have different polarities. The insulating gasket G1 may be interposed between the terminal 40 and the housing 20. The insulating gasket G1 may include an insulating material. The insulating gasket G1 can prevent contact between the terminal 40 and the housing 20, which have different polarities.

[0048] Hereinafter, a battery cell 1 having a structure different from the structure described above will be described with reference to Figures 5 to 11. Figure 5 is a diagram showing a battery cell to which a current collector of a different form from the current collector shown in Figure 1 is applied, Figure 6 is a diagram to explain the fracture of the coupling portion between components due to the increase in internal pressure of the battery cell shown in Figure 5, and Figures 7 and 8 are diagrams showing exemplary forms of current collectors applied to the battery cells shown in Figures 5 and 6. Figure 9 is a diagram to explain the phenomenon in which, in the battery cells shown in Figures 5 and 6, when the CID of one embodiment of the present invention is omitted, the coupling portion between the terminal and the current collector moves together without fracture due to the rising of the terminal. Figure 10 is a diagram to explain the phenomenon in which, in the battery cells shown in Figures 5 and 6, when the CID of one embodiment of the present invention is coupled only to the second coupling portion of the current collector, the coupling portion between the terminal and the CID moves together without fracture due to the rising of the terminal. Figure 11 is a diagram illustrating the phenomenon in which the connection between the terminal and the CID breaks due to the upward movement of the terminal when the CID of one embodiment of the present invention is fully connected to the first and second coupling portions of the current collector in the battery cell shown in Figures 5 and 6.

[0049] First, referring to Figure 5, the current collector 30 may include a first coupling portion 31 and a second coupling portion 32. The first coupling portion 31 may be electrically coupled to the electrode assembly 10. The first coupling portion 31 may be coupled, for example, to the first blank portion 11 of the electrode assembly 10. The second coupling portion 32 may be located at a distance from the first coupling portion 31 along the radial direction of the electrode assembly 10. The second coupling portion 32 may be coupled to the terminal 40 with the CID 50 in between.

[0050] According to the structure of the current collector 30 of this embodiment of the present invention, the first coupling portion 31 provided for coupling with the electrode assembly 10 and the second coupling portion 32 provided for coupling with the terminal 40 are not directly connected to each other but are indirectly connected. Therefore, if an impact is applied to one of the welds formed on the first coupling portion 31 or the second coupling portion 32, the impact is not directly transmitted to the other. This reduces the risk of damage to the weld due to external impact.

[0051] The second coupling portion 32 may be provided at a position corresponding to the winding center hole 10a of the electrode assembly 10. In the drawings, the second coupling portion 32 is shown to be larger in size so as to cover the winding center hole 10a, but the present invention is not limited thereto. The second coupling portion 32 may be substantially the same size as or smaller than the winding center hole 10a.

[0052] Referring to Figures 7 and 8, the current collector 30 may include a connecting portion 33 configured to electrically connect the first connecting portion 31 and the second connecting portion 32. The connecting portion 33 may include a substantially rim-shaped peripheral portion 33a with a hollow center, and a bridge portion 33b connecting the peripheral portion 33a and the second connecting portion 32. One or more bridge portions 33b may be provided. The first connecting portion 31 may extend inward from the peripheral portion 33a. Multiple first connecting portions 31 may be provided. In this case, the second connecting portion 32 may be arranged to be surrounded by multiple first connecting portions 31.

[0053] Referring further to Figure 5, the CID 50 can be coupled to both the first coupling portion 31 and the second coupling portion 32. In this case, when the internal pressure of the battery cell 1 increases, the welded portion between the terminal 40 and the CID 50 breaks rapidly, as shown in Figure 6, thereby quickly interrupting the flow of current through the terminal 40. In this case, the CID 50 can be configured to cover both the first coupling portion 31 and the second coupling portion 32 along the radial direction of the electrode assembly 10.

[0054] Referring to Figure 9, it can be seen that when the CID 50 is omitted and the terminal 40 and the second coupling portion 32 of the current collector 30 are directly coupled, the coupling portion between the terminal 40 and the current collector 30 will not easily break when the terminal 40 rises.

[0055] Referring to Figure 10, it can be seen that when the CID 50 is not connected to the first coupling part 31 but only to the second coupling part 32, the coupling portion between the terminal 40 and the current collector 30 will not easily break when the terminal 40 rises. On the other hand, referring to Figure 11, it can be seen that when the CID 50 is connected to both the first coupling part 31 and the second coupling part 32, the first coupling part 31 and the second coupling part 32, which are separated from each other, are structurally connected (see area C in Figure 11). Therefore, the phenomenon of the second coupling part 32 rising together with the terminal 40 when it rises can be suppressed.

[0056] Hereinafter, an embodiment in which a CID gasket 60 is applied to a battery cell 1 of one embodiment of the present invention will be described with reference to Figures 12 and 15. Figure 12 is a diagram showing a battery cell to which a CID gasket is further applied, in addition to the battery cell shown in Figure 5. Figure 13 is a diagram to illustrate the fracture of the joint between components due to the increase in internal pressure of the battery cell shown in Figure 12. Figures 14 and 15 are diagrams showing a battery cell having a structure in which the CID gasket is positioned in a different location compared to the battery cell shown in Figure 12.

[0057] Referring to Figures 12 and 13, a battery cell 1 of one embodiment of the present invention may include a CID gasket 60. The CID gasket 60 may include an insulating material. The CID gasket 60 may be interposed between the closure portion of the housing 20 and the current collector 30. The CID gasket 60 may maintain separation between the terminal 40 and the CID 50 when separation occurs due to an increase in the internal pressure of the housing 20. The CID gasket 60 may be configured to have an elastic restoring force in the direction of expansion between the closure portion of the housing 20 and the current collector 30. The CID gasket 60 may be interposed between the closure portion and the current collector 30 in a compressed state having a thickness corresponding to the distance between the closure portion and the current collector 30.

[0058] With the application of the CID gasket 60, the closing portion of the housing 20, which has bulged upward due to the increase in internal pressure, can maintain its deformed state without its shape being restored. When the closing portion of the housing 20 deforms and bulges upward, the terminal 40 rises along with it, which can cause the connection between the terminal 40 and the CID 50 to break. When the CID gasket 60 is applied, the separation between the terminal 40 and the CID 50 is maintained, which allows the flow of current through the terminal 40 to be kept interrupted.

[0059] The CID gasket 60 may be configured to expand in response to a rise in the internal temperature of the housing 20. That is, the CID gasket 60 may contain a material that expands with heat. For example, the CID gasket 60 may contain a foamed resin. The CID gasket 60 may be configured to expand at a temperature at which the closing portion of the housing 20 bulges upward.

[0060] The CID gasket 60 may be positioned such that at least a portion of it is interposed between the CID 50 and the closing portion of the housing 20. When the CID gasket 60 is positioned in this manner, the CID gasket 60 can pressurize the coupling portion between the current collector 30 and the electrode assembly 10. Therefore, when the terminal 40 rises, it is possible to prevent the coupling portion between the current collector 30 and the electrode assembly 10 from being damaged before the coupling portion between the terminal 40 and the CID 50 is damaged. To maximize this effect, the entire area of ​​the CID gasket 60 may be located on the CID 50, as shown in Figure 15. However, the position of the CID gasket 60 in the present invention is not limited thereto, and the entire area may be located outside the CID 50, as shown in Figure 14.

[0061] The overall structure and lower structure of the battery cell 1 of one embodiment of the present invention will be described in detail below with reference to Figures 16 to 18. Figure 16 is a diagram showing the external appearance of the battery cell of one embodiment of the present invention, Figure 17 is a diagram showing the overall internal structure of the battery cell shown in Figure 16, and Figure 18 is a partial cross-sectional view showing the lower structure of the battery cell of one embodiment of the present invention.

[0062] Referring to Figures 16 to 18, a battery cell 1 of one embodiment of the present invention may include a battery cap 70 configured to cover an opening in the housing 20. The battery cap 70 may have a vent portion 71 that is weaker than the surrounding area. The vent portion 71 may be configured such that, for example, one or both sides of the battery cap 70 are cut out to have a thinner thickness compared to the surrounding area.

[0063] In the case where the battery cell 1 of the present embodiment is equipped with a vent portion 71, the connection portion between the terminal 40 and the CID 50 of the present embodiment described above may be configured to rupture at a pressure lower than the venting pressure of the vent portion 71, i.e., the pressure at which the vent portion 71 ruptures. This is to ensure the safety of the battery in use by interrupting the flow of current through the terminal 40 before the thermal event caused by venting diffuses.

[0064] A battery cell 1 according to one embodiment of the present invention may include a sealing gasket G2 interposed between the battery cap 70 and the inner surface of the housing 20. The sealing gasket G2 may be configured to enhance the sealing performance of the housing 20.

[0065] On the other hand, in one embodiment of the present invention, the battery cell 1 may be configured such that the terminal 40 and the closing portion of the housing 20 function as a first electrode terminal and a second electrode terminal, respectively. The terminal 40 may be electrically connected to the first blank portion 11 of the electrode assembly 10 through the current collector (first current collector) 30 as described above, thereby having a first polarity. The housing 20 may be electrically connected to the second blank portion 12 of the electrode assembly 10, thereby having a second polarity.

[0066] The electrical connection between the housing 20 and the second blank portion 12 of the electrode assembly 10 may be made, for example, through a second current collector P. The second blank portion 12, like the first blank portion 11 described above, refers to a region on the second electrode that is not coated with electrode active material. The second blank portion 12 may be formed at one end of the second electrode and may extend along the winding direction of the electrode assembly 10. The second blank portion 12 may extend downward along the height direction (parallel to the Z-axis) of the electrode assembly 10. The second current collector P may be coupled onto such a second blank portion 12. The second blank portion 12, like the first blank portion 11 described above, may comprise a plurality of segmental sections, which may be bent toward the core of the electrode assembly 10. The bent segmental sections of the second blank portion 12 may overlap each other to form a plurality of layers. When the segment of the second blank portion 12 is bent in this manner, the second current collector P can be attached to the substantially flat surface formed by the bending of the second blank portion 12.

[0067] The second current collector P may be bonded to the inner surface of the housing 20. The housing 20 may have a beading portion 21 pressed along its outer circumference. The housing 20 may have a crimping portion 22 that extends from the beading portion 21 and is bent to wrap around the periphery of the battery cap 70. The second current collector P may be interposed between one surface of the beading portion 21 and the sealing gasket G2.

[0068] Next, with reference to Figure 19, a battery pack 3 according to one embodiment of the present invention will be described. Figure 19 is a diagram showing a battery pack according to one embodiment of the present invention.

[0069] Referring to Figure 19 in conjunction with Figures 17 and 18, a battery pack 3 according to one embodiment of the present invention may include a battery cell 1 according to one embodiment of the present invention and a pack housing 2 that houses the battery cell 1. Multiple battery cells 1 may be provided, and the multiple battery cells 1 may be electrically connected to each other. As described above, the battery cell 1 of one embodiment of the present invention may be configured such that the terminal 40 and the closing portion of the housing 20 function as a first electrode terminal and a second electrode terminal, respectively (see Figures 17 and 18). Therefore, when multiple battery cells 1 are arranged in the pack housing 2, an electrical connection can be made at the top of the battery cells 1 by arranging all the battery cells 1 so that the terminal 40 faces upward.

[0070] The following describes an automobile 5 according to one embodiment of the present invention with reference to Figure 20. Figure 20 is a diagram showing an automobile according to one embodiment of the present invention.

[0071] Referring to Figure 20, an automobile 5 according to one embodiment of the present invention may include a battery pack 3 according to one embodiment of the present invention. The automobile 5 may be configured to operate by being powered by the battery pack 3. The automobile 5 may be, for example, an electric vehicle or a hybrid vehicle.

[0072] As described above, the present invention has been explained with limited embodiments and drawings, but it goes without saying that the present invention is not limited thereto, and that various modifications and variations are possible within the equivalent scope of the technical concept and claims of the present invention by persons with ordinary skill in the art to which the present invention belongs. [Explanation of Symbols]

[0073] 5: Automobile 3: Battery pack 1: Battery cell 10: Electrode assembly 10a: Winding center hole 11: Plain section (First plain section) 12: Plain section (Second plain section) 20: Housing 21: Beading Section 22: Crimping Department 30: Current collector (first current collector) 31: 1st joint 32:Second joint part 33:Connection part 33a: Peripheral area 33b: Bridge section IS: Insulator 40: Terminals G1: Insulating gasket 50:CID 60: CID Gasket 70: Battery cap 71: Vent section G2: Sealing Gasket P: Current collector (second current collector)

Claims

1. Electrode assembly and A housing comprising an open portion provided on one side and a closed portion formed on the opposite side of the open portion, which houses the electrode assembly through the open portion, A current collector is disposed between the electrode assembly and the closing portion and is electrically coupled to the electrode assembly, A terminal that is electrically coupled to the electrode assembly through the aforementioned closing portion, A CID is interposed between the terminal and the current collector and is coupled to the current collector with a greater coupling force than the terminal, Battery cells containing these cells.

2. The battery cell according to claim 1, wherein the area of ​​the coupling surface between the CID and the current collector is larger than the area of ​​the coupling surface between the CID and the terminal.

3. The battery cell according to claim 1, wherein the coupling surface formed at the lower end of the terminal is provided at a position corresponding to the winding center hole of the electrode assembly.

4. The aforementioned CID is The battery cell according to claim 3, wherein the current collector is coupled to the inside and outside of the region corresponding to the winding central hole.

5. The aforementioned current collector is A first coupling portion electrically coupled to the electrode assembly, A second coupling portion is provided located at a distance from the first coupling portion along the radial direction of the electrode assembly and at a position corresponding to the winding center hole of the electrode assembly, A battery cell according to claim 1, including the battery cell described in claim 1.

6. The aforementioned CID is The battery cell according to claim 5, wherein both the first coupling portion and the second coupling portion are fully coupled.

7. The aforementioned CID is The battery cell according to claim 6, wherein the electrode assembly is configured to cover both the first and second coupling portions along its radial direction.

8. The aforementioned battery cell is The battery cell according to claim 1, comprising a CID gasket interposed between the closing portion and the current collector, the CID gasket maintaining the separated state when separation occurs between the closing portion and the current collector due to an increase in the internal pressure of the housing.

9. The aforementioned CID gasket is The battery cell according to claim 8, wherein the closing portion and the current collector are configured to have an elastic restoring force in the direction of expansion.

10. The aforementioned CID gasket is The battery cell according to claim 8, configured to expand due to an increase in the internal temperature of the housing.

11. The aforementioned CID gasket is The battery cell according to claim 8, wherein at least a portion of it is interposed between the CID and the closing portion.

12. The battery cell includes a battery cap configured to cover the opening, The battery cell according to claim 1, wherein the battery cap is provided with a vent portion that is more fragile than the surrounding area.

13. The battery cell according to claim 12, wherein the connection portion between the terminal and the CID is configured to rupture at a pressure lower than the vent pressure of the vent portion.

14. A battery pack comprising the battery cell described in any one of claims 1 to 13.

15. An automobile comprising the battery pack described in claim 14.

Images