Electrode assembly, battery including same, and battery pack and vehicle including battery

Abstract

An electrode assembly according to an embodiment of the present invention has a structure in which a laminate including a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode is wound. In the electrode assembly, a first electrode and a second electrode may each include: an uncoated portion formed at a longitudinal end and not coated with an active material; and a coating portion coated with an active material. Further, a first insulating layer and a second insulating layer may be disposed on a first surface and a second surface opposite the first surface of the first electrode, respectively, where the first insulating layer and the second insulating layer each extend a predetermined length from a region including a boundary between the coated portion and the uncoated portion toward an end portion of the uncoated portion.

Description

Technical Field

[0001] The present disclosure relates to an electrode assembly, a battery including the electrode assembly, a battery pack including the battery, and a vehicle including the battery pack.

[0002] This application claims priority to Korean Patent Application No. 10-2022-0153750, filed in Korea on November 16, 2022, the disclosure of which is incorporated herein by reference. Background Art

[0003] In a cylindrical secondary battery, a wound core type electrode assembly in which a positive electrode terminal and a negative electrode terminal extend vertically along the height direction of the battery can is applicable to maximize the current collection efficiency.

[0004] In the above structure, movement such as meandering of the positive electrode or the negative electrode may occur. In this case, the end of the positive electrode or the negative electrode may be located near the end of the separator. Therefore, when the positive electrode or the negative electrode is located at the end of the separator or protrudes outward from the end of the separator due to movement such as meandering of the positive electrode or the negative electrode, electrical contact may occur between the positive electrode and the negative electrode. Or, if the separator is damaged for any reason, electrical contact may occur between the positive electrode and the negative electrode. Therefore, a short circuit may occur inside the battery. If a short circuit occurs inside the battery, the battery may heat up or explode. Therefore, an insulating member needs to be provided to effectively prevent electrical contact between the positive electrode and the negative electrode.

[0005] Therefore, a method is needed to provide a battery cell having a low internal resistance of the secondary battery and also having a low risk of short circuit, as well as a battery pack and a vehicle including the battery cell. Summary of the Invention

[0006] Technical Problem

[0007] The present disclosure aims to solve the problems of the prior art, and thus the present disclosure aims to reduce the internal resistance of the battery.

[0008] The present disclosure also aims to effectively prevent an internal short circuit of the battery.

[0009] However, the technical objects to be solved by the present disclosure are not limited to the above, and other objects not mentioned herein will be clearly understood by those skilled in the art from the following disclosure.

[0010] Technical Solution

[0011] In one aspect of the present disclosure, an electrode assembly is provided, which has a structure in which a laminate including a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode is wound. Wherein, the first electrode and the second electrode respectively have uncoated portions provided at long side ends and not coated with active material and coated portions coated with active material, and wherein, on a first surface and a second surface opposite to the first surface of the first electrode, a first insulating layer and a second insulating layer are respectively provided, and the first insulating layer and the second insulating layer extend a predetermined length from a region including the boundary between the coated portion and the uncoated portion toward the end of the uncoated portion.

[0012] The uncoated portion may include: a plurality of uncoated portion slotted valleys formed along the winding direction of the electrode assembly; and a plurality of segments formed to be spaced apart from each other along the winding direction such that the plurality of uncoated portion slotted valleys are respectively interposed between the plurality of segments.

[0013] Each of the first insulating layer and the second insulating layer may have an insulating layer slotted valley formed at a position corresponding to the uncoated portion slotted valley, and the depth of the insulating layer slotted valley corresponds to the depth of the uncoated portion slotted valley.

[0014] In the region where the insulating layer slotted valley is formed, on the first surface of the first electrode, the edge cutting surface of each of the plurality of segments may be exposed outside the first insulating layer, and on the second surface of the first electrode, the edge cutting surface of each of the plurality of segments may not be exposed outside the second insulating layer.

[0015] The first surface of the first electrode may be the surface facing the outside of the electrode assembly, and the second surface of the first electrode may be the surface facing the inside of the electrode assembly.

[0016] In the region where the insulating layer slotted valley is formed, the edge cutting surface of the laminate including the first insulating layer, the segment, and the second insulating layer may be inclined such that the area of the second insulating layer is larger than the area of the first insulating layer.

[0017] The plurality of segments may be bent along the radial direction of the electrode assembly.

[0018] Each of the first insulating layer and the second insulating layer may have an insulating layer slotted valley formed at a position corresponding to the uncoated portion slotted valley, and the depth of the insulating layer slotted valley corresponds to the depth of the uncoated portion slotted valley.

[0019] In the region where the grooved valley of the insulating layer is formed, on the first surface of the first electrode, the edge cutting surface of each of the plurality of segments can be exposed outside the first insulating layer, and on the second surface of the first electrode, the edge cutting surface of each of the plurality of segments may not be exposed outside the second insulating layer.

[0020] The first surface of the first electrode may be the surface located in the direction opposite to the bending direction of the segment, and the second surface of the first electrode may be the surface located in the bending direction of the segment.

[0021] In the region where the grooved valley of the insulating layer is formed, the edge cutting surface of the laminate including the first insulating layer, the segment, and the second insulating layer may be inclined such that the area of the second insulating layer is larger than the area of the first insulating layer.

[0022] In another aspect of the present disclosure, there is also provided a method for manufacturing an electrode assembly, the method for manufacturing the electrode assembly including the following steps: an electrode preparation step of preparing a first electrode having insulating layers provided on both of its surfaces; a segment formation step of forming a plurality of segments by irradiating a laser on the first surface of the first electrode to groove the uncoated portion of the first electrode; a laminate preparation step of forming a laminate including the first electrode; and a winding step of winding the laminate to form an electrode assembly.

[0023] The method for manufacturing the electrode assembly may further include the step of orienting the first surface of the first electrode on which the laser irradiation is performed toward the outside of the electrode assembly.

[0024] The method for manufacturing the electrode assembly may further include the step of bending the plurality of segments along the radial direction of the electrode assembly.

[0025] The winding step may include the step of positioning the first surface of the first electrode on which the laser irradiation is performed in the direction opposite to the bending direction of the segment.

[0026] In another aspect of the present disclosure, there is also provided a battery, the battery including: an electrode assembly according to the present disclosure; and a housing configured to accommodate the electrode assembly.

[0027] In another aspect of the present disclosure, there is also provided a battery pack, the battery pack including a battery according to an embodiment of the present disclosure.

[0028] In another aspect of the present disclosure, there is also provided a vehicle, the vehicle including a battery pack according to an embodiment of the present disclosure.

[0029] Advantageous Effects

[0030] According to one aspect of the present disclosure, the internal resistance of the battery can be greatly reduced, and thus a battery that is beneficial for fast charging and fast discharging can be provided.

[0031] According to another aspect of the present disclosure, internal short - circuit of the battery can be effectively prevented, and thus the safety of the secondary battery during use can be greatly improved.

[0032] However, the beneficial effects that can be obtained through the present disclosure are not limited to the above - mentioned effects, and those skilled in the art will clearly understand other beneficial effects not mentioned above through the following disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings illustrate preferred embodiments of the present disclosure and, together with the above - mentioned disclosure, are used to provide a further understanding of the technical features of the present disclosure. Therefore, the present disclosure is not to be construed as limited to the drawings.

[0034] Figure 1 is a view showing a wound core according to an embodiment of the present disclosure, the wound core having a structure in which a laminate including a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode is wound for manufacturing an electrode assembly.

[0035] Figure 2 is a view showing a part of a longitudinal cross - section of an electrode assembly according to an embodiment of the present disclosure.

[0036] Figure 3 is a view showing a first electrode and an insulating layer applied to an electrode assembly according to an embodiment of the present disclosure.

[0037] Figure 4 is a view showing in a laminate including Figure 3 the first electrode shown and an insulating layer provided on both its surfaces, the cross - sectional shape of the laminate cut by laser grooving.

[0038] Figure 5 is a perspective view of an electrode assembly according to another embodiment of the present disclosure.

[0039] Figure 6 is a view showing Figure 5 a part of a longitudinal cross - section of the electrode assembly shown.

[0040] Figure 7 is a view showing a battery according to an embodiment of the present disclosure.

[0041] Figure 8 is a view showing Figure 7 a cross - sectional view of the internal structure of the battery shown.

[0042] Figure 9 is a view showing a battery pack according to an embodiment of the present disclosure.

[0043] Figure 10 is a view showing a vehicle according to an embodiment of the present disclosure. Detailed Implementation Modes

[0044] In the following, preferred implementation modes of the present disclosure will be described in detail with reference to the accompanying drawings. Before the description, it should be understood that the terms used in the specification and the appended claims should not be construed as being limited to the general and dictionary meanings, but should be interpreted based on the principle that allows the inventor to appropriately define the terms for the best interpretation, according to the meanings and concepts corresponding to the technical aspects of the present disclosure. Therefore, the descriptions presented herein are only preferred examples for illustrative purposes and are not intended to limit the scope of the present disclosure. Thus, it should be understood that other equivalent and modifications can be made without departing from the scope of the present disclosure.

[0045] Referring to Figures 1 to 4 , the electrode assembly 10 according to an implementation mode of the present disclosure will be described.

[0046] Figure 1 FIG. is a view showing a core according to an implementation mode of the present disclosure, the core having a structure in which a laminate including a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode is wound for manufacturing an electrode assembly, Figure 2 FIG. is a view showing a part of a longitudinal section of an electrode assembly according to an implementation mode of the present disclosure. Figure 3 FIG. is a view showing a first electrode and an insulating layer applied to an electrode assembly according to an implementation mode of the present disclosure, Figure 4 FIG. is a view showing a cross-sectional shape of a laminate cut by laser grooving in a laminate including Figure 3 the first electrode shown in and insulating layers provided on both of its surfaces.

[0047] Referring to Figures 1 to 4 , the electrode assembly 10 according to an implementation mode of the present disclosure may include a first electrode 11, a second electrode 12, and a separator 13 interposed between the first electrode 11 and the second electrode 12. The first electrode 11 may be a positive electrode. The second electrode 12 may be a negative electrode.

[0048] For example, the electrode assembly 10 may have a structure in which a laminate including the first electrode 11, the second electrode 12, and the separator 13 is wound. In other words, the electrode assembly 10 may be a core-type electrode assembly. In addition, an additional separator 13 may be provided on the outer peripheral surface of the electrode assembly 10 for insulation.

[0049] Each of the first electrode 11 and the second electrode 12 may include uncoated portions 11a, 12a that are not coated with the electrode active material and coated portions 11b, 12b that are coated with the electrode active material. The uncoated portions 11a, 12a may correspond to regions where the active material layer is not coated at the long side ends of each of the first electrode 11 and the second electrode 12. The coated portions 11b, 12b are regions other than the uncoated portions 11a, 12a and may be regions coated with the active material layer. The uncoated portions 11a, 12a themselves may be used as electrode joints.

[0050] The first electrode 11 and the second electrode 12 may be arranged such that the uncoated portion 11a of the first electrode 11 and the uncoated portion 12a of the second electrode 12 are located on opposite sides. For example, in the electrode assembly 10, the uncoated portion 11a of the first electrode 11 may extend in the upper direction of the electrode assembly 10, and the uncoated portion 12a of the second electrode 12 may extend in the lower direction of the electrode assembly 10.

[0051] In addition, the coated portions 11b, 12b may include sliding portions where the thickness of the active material layer is reduced compared to the central region of the coated portions 11b, 12b. For example, referring to Figure 2 , each of the first electrode 11 and the second electrode 12 may have a sliding portion at one end or the other end, which is a region where the thickness of the active material layer is reduced.

[0052] The sliding portion may be formed by a sliding phenomenon that occurs near the boundary between the coated portion and the uncoated portion when the electrode active material is coated on the electrode current collector. The sliding phenomenon refers to the phenomenon that, due to the diffusion of the slurry containing the electrode active material, less electrode active material is coated in the slurry coating boundary region than in the regions outside the slurry coating boundary region, such that the slurry in the coating boundary region has a substantially inclined shape. Due to the sliding phenomenon, a sliding portion may be formed at the edge of the coated portions 11b, 12b, which has a shape that slopes substantially downward along the direction from the coated portions 11b, 12b toward the uncoated portions 11a, 12a. In this way, during the process of drying the active material, the sliding phenomenon that occurs during the process of coating the active material may become more severe. In other words, when the electrodes 11, 12 on which the sliding portions have already been formed are dried as a whole, the solvent contained in the slurry evaporates, causing the volume of the slurry to decrease. Therefore, near the boundary between the region coated with the electrode active material and the region not coated with the electrode active material, the sliding phenomenon may become more severe.

[0053] The sliding portion may be formed in the boundary region between the coated portions 11b, 12b and the uncoated portions 11a, 12a. For example, the sliding portion may be provided at one end of the first electrode 11 and the other end of the second electrode 12, respectively. That is, the sliding portion of the coated portion 11b provided in the first electrode 11 and the sliding portion of the coated portion 12b provided in the second electrode 12 may be provided in opposite directions. For example, referring to Figure 2 , the sliding portion of the first electrode 11 may be formed upward along the winding axis direction (the direction parallel to the Z-axis), and the sliding portion of the second electrode 12 may be formed downward in the opposite direction along the winding axis direction (i.e., downward).

[0054] In addition, the length of the coated portion 11b provided in the first electrode 11 along the winding axis direction may be shorter than the length of the coated portion 12b provided in the second electrode 12 along the winding axis direction. In addition, the coated portion 11b provided in the first electrode 11 may be positioned more inward along the winding axis direction than the coated portion 12b provided in the second electrode 12. For example, referring to Figure 2 , the length of the coated portion 12b provided in the second electrode 12 along the winding axis direction may be formed to be larger than the length of the coated portion 11b provided in the first electrode 11 along the winding axis direction. In addition, the length of the coated portion 11b provided in the first electrode 11 along the winding axis direction may be shorter than the length of the region other than the sliding portion of the coated portion 12b provided in the second electrode 12 along the winding axis direction. This structure is designed to prevent lithium metal precipitation due to the NP ratio of the positive electrode / negative electrode being reduced to 100% or less.

[0055] In addition, the coated portions 11b, 12b may not protrude more outward than the separator 13 along the winding axis direction. In other words, if the coated portions 11b, 12b protrude more outward than the separator 13 along the winding axis direction, the possibility of contact between the first electrode 11 and the second electrode 12 may increase. If this occurs, an internal short circuit may occur in the contact region, which may increase the risk of ignition. Therefore, it may be advantageous that the coated portions 11b, 12b do not protrude outward more than the separator 13 along the winding axis direction. That is, it may be advantageous that the coated portions 11b, 12b are positioned more inward than the separator 13.

[0056] In addition, the insulating layer 14 may be provided in a part of the first electrode 11. The insulating layer 14 may include a first insulating layer 14a and a second insulating layer 14b. On the first surface A of the first electrode 11 and on the second surface B opposite to the first surface A, the first insulating layer 14a and the second insulating layer 14b may be provided to extend a predetermined length from the region including the boundary (the portion shown by the dashed line) between the coated portions 11b, 12b and the uncoated portions 11a, 12a toward the ends of the uncoated portions 11a, 12a. The insulating layer 14 may reduce the possibility of contact between the first electrode 11 and the second electrode 12. The insulating layer 14 may be configured to cover at least a part of the uncoated portion 11a of the first electrode 11 and at least a part of the coated portion 11b. The insulating layer 14 may be configured to effectively prevent electrical contact between the uncoated portion 11a of the first electrode 11 and the coated portion 12b of the second electrode 12.

[0057] The insulating layer 14 may be provided in the entire region of the first electrode 11 that is likely to face the coated portion 12b provided in the second electrode 12. For example, one end of the insulating layer 14 in the winding axis direction may be at the same height as or more outward than one end of the separator 13 in the winding axis direction. For example, one end of the insulating layer 14 in the winding axis direction may be at the same height as one end of the separator 13 in the winding axis direction. The separator 13 may protrude between the first electrode 11 and the second electrode 12 at the same height as or higher than the distal end of the second electrode 12 in the winding axis direction, thereby reducing the possibility of electrical contact between the first electrode 11 and the second electrode 12.

[0058] However, during the winding process of manufacturing the electrode assembly 10, the electrodes 11, 12 may become zigzag, and during the process of manufacturing / using the secondary battery, the separator 13 may be damaged. If this phenomenon occurs, the first electrode 11 and the second electrode 12 may come into contact with each other. In particular, if an internal short circuit occurs due to contact between the uncoated portion 11a of the first electrode 11 and the coated portion 12b of the second electrode 12, the possibility of ignition increases significantly. Therefore, in order to prevent electrical contact between the first electrode 11 and the second electrode 12, it is advantageous that the insulating layer 14 provided on the first electrode 11 extends at least to the same height as one end of the separator 13 in the winding axis direction or extends more outward than one end of the separator 13 in the winding axis direction.

[0059] However, if the insulating layer 14 covers the entire uncoated portion 11a provided in the first electrode 11, the first electrode 11 cannot be used as an electrode terminal. Therefore, the insulating layer 14 needs to be configured to cover only a part of the uncoated portion 11a provided in the first electrode 11. That is, the uncoated portion 11a can be configured to protrude more outward than the insulating layer 14.

[0060] The insulating layer 14 can be an insulating coating or an insulating tape provided on the boundary region between the uncoated portion 11a and the coated portion 11b. However, the form of the insulating layer 14 is not limited thereto, and any form can be adopted in the present disclosure as long as the insulating layer 14 can be attached to the first electrode 11 while ensuring insulation performance. In addition, the insulating layer 14 can include, for example, an organic SBR binder and alumina to ensure insulation performance.

[0061] The insulating layer 14 can simultaneously cover at least a part of the uncoated portion 11a and at least a part of the coated portion 11b. For example, the insulating layer 14 can be provided on the boundary region between the coated portion 11b and the uncoated portion 11a. For example, the insulating layer 14 can cover at least a part of the sliding portion.

[0062] If the insulating layer 14 is not provided, there is a possibility of an internal short circuit due to the contact between the first electrode 11 and the second electrode 12. Therefore, it is desirable that the insulating layer 14 extends to a position where the first electrode 11 and the second electrode 12 are not in electrical contact with each other.

[0063] If the insulating layer 14 covers a part of the coated portion 11b provided in the first electrode 11, there will be a loss of battery capacity. Therefore, it is necessary to minimize the length of the coated portion covered by the insulating layer 14. However, since there is a possibility that the coated portion 11b provided in the first electrode 11 contacts the second electrode 12, to prevent this, the insulating layer 14 can be configured to cover at least a part of the coated portion 11b provided in the first electrode 11.

[0064] In addition, if the first electrode 11 is a positive electrode and the second electrode 12 is a negative electrode, considering process efficiency, productivity, etc. and the risk of short circuit, the insulating layer 14 can be formed on the uncoated portion 11a of the first electrode 11, and the insulating layer 14 can not be applied to the uncoated portion 12a in the second electrode 12. This is because the risk is greatest when the uncoated portion of the positive electrode and the coated portion of the negative electrode are in contact with each other. The risk differences in various cases where the positive electrode and the negative electrode are in contact with each other will be described in detail later with reference to Figure 10 In addition, the present disclosure does not exclude the case where the insulating layer 14 is provided on the uncoated portion 12a of the second electrode 12.

[0065] In addition, with reference to Figure 3, the uncoated portion 11a may have a plurality of uncoated portion slotted valleys formed along the winding direction of the electrode assembly 10. The uncoated portion slotted valleys may be formed by slitting and removing a part of the uncoated portion 11a by means of laser slitting. The uncoated portion 11a may include a plurality of segments F spaced apart from each other along the winding direction of the electrode 11, such that the plurality of uncoated portion slotted valleys are respectively interposed between the plurality of segments F. In addition, segments F may also be formed in the uncoated portion 12a of the second electrode 12.

[0066] Each of the first insulating layer 14a and the second insulating layer 14b may have an insulating layer slotted valley formed at a position corresponding to the uncoated portion slotted valley, and the depth thereof corresponds to the depth of the uncoated portion slotted valley. That is, through the process of slitting the uncoated portion 11a to form segments F to remove a part of the uncoated portion 11a, the insulating layer 14 covering a part of the uncoated portion 11a is also slotted together, so that a part of the area of the insulating layer 14 is also removed.

[0067] In addition, referring to Figure 3 and Figure 4 , in the region where the insulating layer slotted valley is formed, on the first surface A of the first electrode 11, the edge cutting surface E of each of the plurality of segments F may be exposed outside the first insulating layer 14a. In addition, on the second surface B of the first electrode 11, the edge cutting surface E of each of the plurality of segments F may not be exposed outside the second insulating layer 14b. That is, in the region where the insulating layer slotted valley is formed, the edge cutting surface E of the laminate including the first insulating layer 14a, the segment F, and the second insulating layer 14b may be inclined such that the area of the second insulating layer 14b is larger than the area of the first insulating layer 14a.

[0068] This is because the width of the laser irradiated for slitting gradually decreases from the light source to the irradiation point. According to the characteristics of the laser, the cutting surface E formed on the laminate of the uncoated portion 11a and the insulating layer 14 by laser slitting may not be parallel to the lamination direction, but may be inclined at a predetermined angle with respect to the lamination direction.

[0069] The first surface A of the first electrode 11 may be the surface facing the outside of the electrode assembly 10. The second surface B of the first electrode 11 may be the surface facing the inside of the electrode assembly 10. By arranging the first surface A and the second surface B of the first electrode 11 in this way, when the segment F on the first electrode 11 is subjected to a force bending toward the core and / or when the diaphragm between the first electrode 11 and the second electrode 12 is damaged, the uncoated portion 11a of the first electrode 11 can be effectively prevented from contacting the coated portion 12b of the second electrode 12.

[0070] Next, referring to Figure 5 andFigure 6 and Figure 3 and Figure 4 , an electrode assembly 10 according to another embodiment of the present disclosure will be described.

[0071] Figure 5 is a perspective view showing an electrode assembly according to another embodiment of the present disclosure, Figure 6 shows Figure 5 a view of a part of a longitudinal section of the shown electrode assembly.

[0072] Referring to Figure 5 and Figure 6 and Figure 3 and Figure 4 , the electrode assembly 10 according to another embodiment of the present disclosure may have a structure in which a plurality of segments F formed in the uncoated portion 11a are bent along the radial direction of the electrode assembly 10. The segments F bent in this way may overlap each other to form a plurality of layers.

[0073] As in the previous embodiment, each of the first insulating layer 14a and the second insulating layer 14b may have an insulating layer slotted valley formed at a position corresponding to the uncoated portion slotted valley, and the depth thereof corresponds to the depth of the uncoated portion slotted valley. In the region where the insulating layer slotted valley is formed, on the first surface A of the first electrode 11, the edge cutting surface E of each of the plurality of segments F may be exposed outside the first insulating layer 14a, while on the second surface B of the first electrode 11, the edge cutting surface E of each of the plurality of segments F may not be exposed outside the second insulating layer 14b.

[0074] The first surface A of the first electrode 11 may be the surface located in the direction opposite to the bending direction of the segment F, and the second surface B of the first electrode 11 may be the surface located in the bending direction of the segment F. For example, if the plurality of segments F are bent in the direction toward the winding center of the electrode assembly 10 (i.e., toward the core), the second surface B may be located in the direction toward the inside of the electrode assembly 100, and the first surface A may be located in the direction facing the outside of the electrode assembly 10.

[0075] In the region where the insulating layer slotted valley is formed, the edge cross-section of the laminate including the first insulating layer 14a, the segment F, and the second insulating layer 14b may be inclined such that the area of the second insulating layer 14b is larger than the area of the first insulating layer 14a.

[0076] Since the electrode assembly 10 of the present disclosure is configured such that the first surface A of the first electrode 11 located in the direction of performing laser irradiation for forming the segment F faces the outside of the electrode assembly 10 as described above, deterioration of the insulating effect of the insulating layer 14 can be prevented.

[0077] Next, with reference to Figure 7 and Figure 8 , the battery 1 according to an embodiment of the present disclosure will be described.

[0078] Figure 7 is a diagram showing a battery according to an embodiment of the present disclosure, Figure 8 is showing Figure 7 a cross-sectional view of the internal structure of the battery shown.

[0079] With reference to Figure 7 and Figure 8 , the battery 1 according to an embodiment of the present disclosure may include the electrode assembly 10 according to the present disclosure described above. The battery 1 may be, for example, a cylindrical battery. The battery 1 may include an electrode assembly 10, a case 20, a cap 30, and a terminal 40. In addition to the above components, the battery 1 may further include a first current collector 50 and / or an insulator 60 and / or an insulating washer 70 and / or a second current collector 80 and / or a sealing washer 90.

[0080] With reference to Figure 7 and Figure 8 , the case 20 may be a substantially cylindrical receiver having an opening formed at the bottom. The case 20 may include a conductive material, such as a metal. The case 20 may include, for example, aluminum. The bottom of the case 20 provided with the opening will be referred to as the open end. The side surface (outer periphery) and the upper surface of the case 20 may be formed integrally. The upper surface of the case 20 (the surface parallel to the X-Y plane) may have an approximately flat shape. The upper surface located on the opposite side of the open end is referred to as the closed end. The case 20 houses the electrode assembly 10 through the opening formed at the bottom, and may also house an electrolyte.

[0081] The case 20 may be electrically connected to the electrode assembly 10. The case 20 may be electrically connected to one of the first electrode 11 and the second electrode 12. For example, the case 20 may be electrically connected to the second electrode 12 of the electrode assembly 10. In this case, the case 20 may have the same polarity as the second electrode 12.

[0082] The case 20 may include a crimped portion 21 and / or a caulked portion 22 formed at its lower end. The crimped portion 21 may be formed in the lower part of the electrode assembly 10. The crimped portion 21 may be formed by press-fitting the outer peripheral surface of the case 20. The crimped portion 21 may prevent the electrode assembly 10, which may have a size approximately corresponding to the width of the case 20, from escaping through the opening formed at the bottom of the case 20. The crimped portion 21 may serve as a support on which the cap 30 is placed.

[0083] The crimping portion 22 can be formed below the curled portion 21. The crimping portion 22 can have an extended and curved shape to surround the outer peripheral surface of the cap 30 disposed below the curled portion 21 and a part of the lower surface of the cap 30.

[0084] The cap 30 can include, for example, a metallic material to ensure rigidity. The cap 30 can cover the opening portion formed at the bottom of the housing 20. The cap 30 can form the lower surface of the battery 1. In the battery 1 of the present disclosure, even if the cap 30 is made of a conductive metallic material, the cap 30 may not have a polarity. The fact that the cap 30 does not have a polarity can mean that the cap 30 is electrically insulated from the housing 20 and the terminal 40. Therefore, the cap 30 can not be used as a positive terminal or a negative terminal. The cap 30 does not have to be electrically connected to the electrode assembly 10 and the housing 20, and its material does not have to be metal.

[0085] If the housing 20 of the present disclosure includes a curled portion 21, the cap 30 can be placed on the curled portion 21 formed in the housing 20. Further, when the housing 20 of the present disclosure includes a crimping portion 22, the cap 30 can be fixed by the crimping portion 22. A sealing gasket 90 can be interposed between the cap 30 and the crimping portion 22 of the housing 20 to ensure the airtightness of the housing 20.

[0086] The terminal 40 can be electrically connected to either the first electrode 11 or the second electrode 12. The terminal 40 can be configured to have a polarity opposite to that of the housing 20. For example, the terminal 40 can be electrically connected to the first electrode 11. The terminal 40 can be exposed to the outside of the housing 20.

[0087] The terminal 40 can include a conductive metallic material. For example, the terminal 40 can generally pass through the center of the closed end formed at the top of the housing 20. A part of the terminal 40 can be exposed to the upper part of the housing 20, and the remaining part can be located inside the housing 20. The terminal 40 can be fixed on the inner surface of the closed end of the housing 20 by, for example, riveting. The terminal 40 can pass through the insulator 60 and be coupled to the first current collector 50 or the uncoated portion 11a provided in the first electrode 11. In this case, the terminal 40 can have a first polarity. Therefore, the terminal 40 can be used as the first electrode terminal in the battery 1 of the present disclosure. If the terminal 40 has a first polarity, the terminal 40 can be insulated from the housing 20 having a second polarity. The terminal 40 and the housing 20 can be insulated by interposing an insulating gasket 70 therebetween.

[0088] The first current collector 50 can be coupled to the upper part of the electrode assembly 10. For example, the first current collector 50 can be coupled to the uncoated portion 11a provided in the first electrode 11 at the upper part of the electrode assembly 10. The first current collector 50 can include a conductive metallic material. The first current collector 50 can be coupled to the end of the uncoated portion 11a provided in the first electrode 11.

[0089] The first current collector 50 may be coupled to a coupling surface formed by bending an end portion of the uncoated portion 11a provided in the first electrode 11 in a direction parallel to the first current collector 50. The bending direction of the uncoated portion 11a may be, for example, a direction toward the winding center C of the electrode assembly 10. If the uncoated portion 11a has the bent shape as described above, the space occupied by the uncoated portion 11a is reduced, which may improve the energy density. In addition, as the coupling area between the uncoated portion 11a and the first current collector 50 increases, the coupling strength may be improved and the resistance may be reduced.

[0090] The insulator 60 may be provided between the top of the electrode assembly 10 and the inner surface of the housing 20, or between the first current collector 50 coupled to the upper portion of the electrode assembly 10 and the inner surface of the housing 20. The insulator 60 may prevent contact between the uncoated portion 11a provided in the first electrode 11 and the housing 20 and / or between the first current collector 50 and the housing 20. The insulator 60 is accommodated inside the housing 20 and may be configured to block the electrical connection between the uncoated portion 11a provided in the first electrode 11 and the housing 20. Accordingly, the insulator 60 may include a material having insulating properties.

[0091] The insulating washer 70 is interposed between the housing 20 and the terminal 40 to prevent the housing 20 and the terminal 40 having opposite polarities from contacting each other. In other words, the insulating washer 70 blocks the electrical connection between the housing 20 and the terminal 40. As a result, the upper surface of the housing 20 having a substantially flat shape may be used as the second electrode terminal of the battery 1.

[0092] The second current collector 80 may be coupled to the lower portion of the electrode assembly 10. The second current collector 80 may be made of a conductive metal material. The second current collector 80 may be connected to the uncoated portion 12a provided in the second electrode 12. In addition, the second current collector 80 may be electrically connected to the housing 20. The second current collector 80 may be interposed and fixed between the inner surface of the housing 20 and the sealing washer 90. Alternatively, the second current collector 80 may be welded to the inner wall of the housing 20.

[0093] The second current collector 80 may be coupled to a coupling surface formed by bending an end portion of the uncoated portion 12a provided in the second electrode 12 in a direction parallel to the second current collector 80. The bending direction of the uncoated portion 12a provided in the second electrode 12 may be, for example, a direction toward the winding center C of the electrode assembly 10. If the uncoated portion 12a provided in the second electrode 12 has the bent shape as described above, the space occupied by the uncoated portion 12a is reduced, which may improve the energy density. In addition, as the coupling area between the uncoated portion 12a and the second current collector 80 increases, the coupling strength may be improved and the resistance may be reduced.

[0094] The sealing gasket 90 may have a substantially annular shape around the cap 30. The sealing gasket 90 may cover the lower surface, upper surface, and side surface of the cap 30 simultaneously. The radial length of the portion of the sealing gasket 90 covering the upper surface of the cap 30 may be less than or equal to the radial length of the portion of the sealing gasket 90 covering the lower surface of the cap 30. If the radial length of the portion of the sealing gasket 90 covering the upper surface of the cap 30 is too long, the sealing gasket 90 presses the second current collector 80 during the sizing process of vertically compressing the housing 20, which may cause damage to the second current collector 80 or the housing 20. Therefore, it may be advantageous to keep the radial length of the portion of the sealing gasket 90 covering the upper surface of the cap 30 small to a certain level.

[0095] Next, reference will be made to Figures 1 to 6 a method of manufacturing the electrode assembly 10 of the present disclosure will be described.

[0096] The method of manufacturing the electrode assembly 10 of the present disclosure may include an electrode preparation step, a segmentation formation step, a laminate preparation step, and a winding step. The electrode preparation step may be a step of preparing the first electrode 11 provided with the insulating layer 14 on both of its surfaces. The segmentation formation step may be a step of forming a plurality of segments F by irradiating a laser on the first surface A of the first electrode 11 and grooving the uncoated portion 11a of the first electrode 11. The laminate preparation step may be a step of forming a laminate including the first electrode 11. In addition to the first electrode 11, the laminate may further include the second electrode 12 and the separator 13. The winding step may be a step of winding the prepared laminate to form the electrode assembly 10.

[0097] The method of manufacturing the electrode assembly of the present disclosure may include a step of orienting the first surface A of the first electrode 11 on which the laser irradiation is performed toward the outside of the electrode assembly 10. As described above, by directing the first surface A on which the laser irradiation is performed outward, the risk of short circuit caused when the cut surface of the segment F is exposed at the edge of the insulating layer 14 by the laser irradiation can be eliminated or minimized.

[0098] The method of manufacturing the electrode assembly of the present disclosure may include a step of bending a plurality of segments F in one direction along the radial direction of the electrode assembly 10. In this case, the winding step may include a step of positioning the first surface A of the first electrode 11 on which the laser irradiation is performed in a direction opposite to the bending direction of the segments F. As described above, by positioning the first surface A on which the laser irradiation is performed on the opposite side of the bending direction of the segments F, the risk of short circuit caused when the cut surface of the segment F is exposed at the edge of the insulating layer 14 by the laser irradiation can be eliminated or minimized.

[0099] Next, reference is made to Figure 9, the battery pack 3 according to an embodiment of the present disclosure will be described.

[0100] Figure 9 is a diagram showing a battery pack according to an embodiment of the present disclosure.

[0101] Referring to Figure 9 , the battery pack 3 according to an embodiment of the present disclosure may include the battery 1 of the present disclosure. The battery pack 3 may include components in which a plurality of batteries 1 are electrically connected and a battery pack housing 2 that houses the components. In the figure, for ease of illustration, components such as bus bars, cooling units, and external terminals for electrically connecting to the battery 1 are not shown.

[0102] Next, referring to Figure 10 , the vehicle 5 according to an embodiment of the present disclosure will be described.

[0103] Figure 10 is a diagram showing a vehicle according to an embodiment of the present disclosure.

[0104] Referring to Figure 10 , the vehicle 5 may include the battery pack 3 of the present disclosure. The battery pack 3 may be installed in the vehicle 5. The vehicle 5 of the present disclosure may be, for example, an electric vehicle, a hybrid electric vehicle, or a plug-in hybrid vehicle. The vehicle may include a four-wheeled vehicle or a two-wheeled vehicle. According to an embodiment of the present disclosure, the vehicle 5 may be configured to operate by receiving power from the battery pack 3.

[0105] The present disclosure has been described in detail. However, it should be understood that when indicating the preferred embodiments of the present disclosure, the detailed description and specific examples are given only by way of illustration, because various modifications and variations within the scope of the present disclosure will become apparent to those skilled in the art through the detailed description.

[0106] [Reference Signs]

[0107] 1: Battery

[0108] 2: Battery pack housing

[0109] 3: Battery pack

[0110] 5: Vehicle

[0111] 10: Electrode assembly

[0112] 11: First electrode

[0113] 12: Second electrode

[0114] 11a, 12a: Uncoated portion

[0115] 11b, 12b: Coated portion

[0116] F: Segment

[0117] 13: Diaphragm

[0118] 14: Insulating layer

[0119] 14a: First insulating layer

[0120] 14b: Second insulating layer

[0121] A: First surface

[0122] B: Second surface

[0123] 20: Housing

[0124] 21: Crimped part

[0125] 22: Pressing part

[0126] 30: Cap

[0127] 40: Terminal

[0128] 50: First current collector

[0129] 60: Insulator

[0130] 70: Insulating washer

[0131] 80: Second current collector

[0132] 90: Sealing washer

Claims

1. An electrode assembly having a structure in which a laminate including a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode is wound. Among them, The first electrode and the second electrode each have an uncoated portion provided at a long-side end and not coated with an active material and a coated portion coated with the active material, and wherein a first insulating layer and a second insulating layer are respectively provided on a first surface and a second surface opposite to the first surface of the first electrode, and the first insulating layer and the second insulating layer extend a predetermined length from a region including a boundary between the coated portion and the uncoated portion toward an end of the uncoated portion.

2. The electrode assembly according to claim 1, Among them, the uncoated portion includes a plurality of uncoated portion slotted valleys formed along a winding direction of the electrode assembly, and wherein the uncoated portion includes a plurality of segments formed to be spaced apart from each other along the winding direction such that the plurality of uncoated portion slotted valleys are respectively interposed between the plurality of segments.

3. The electrode assembly according to claim 2, Among them, each of the first insulating layer and the second insulating layer has an insulating layer slotted valley formed at a position corresponding to the uncoated portion slotted valley, and a depth of the insulating layer slotted valley corresponds to a depth of the uncoated portion slotted valley.

4. The electrode assembly according to claim 3, Among them, in a region where the insulating layer slotted valley is formed, on the first surface of the first electrode, an edge cutting surface of each of the plurality of segments is exposed outside the first insulating layer, and on the second surface of the first electrode, the edge cutting surface of each of the plurality of segments is not exposed outside the second insulating layer.

5. The electrode assembly according to claim 4, Among them, the first surface of the first electrode is a surface facing the outside of the electrode assembly, and wherein the second surface of the first electrode is a surface facing the inside of the electrode assembly.

6. The electrode assembly according to claim 3, Among them, in a region where the insulating layer slotted valley is formed, an edge cutting surface of a laminate including the first insulating layer, the segment, and the second insulating layer is inclined such that an area of the second insulating layer is larger than an area of the first insulating layer.

7. The electrode assembly according to claim 2, Among them, the plurality of segments are bent along a radial direction of the electrode assembly.

8. The electrode assembly according to claim 7, Among them, each of the first insulating layer and the second insulating layer has an insulating layer slotted valley formed at a position corresponding to the uncoated portion slotted valley, and a depth of the insulating layer slotted valley corresponds to a depth of the uncoated portion slotted valley.

9. The electrode assembly according to claim 8, Among them, In the region where the grooved valley of the insulating layer is formed, on the first surface of the first electrode, the edge cutting surfaces of each of the plurality of segments are exposed outside the first insulating layer, and on the second surface of the first electrode, the edge cutting surfaces of each of the plurality of segments are not exposed outside the second insulating layer.

10. The electrode assembly according to claim 9, Among them, The first surface of the first electrode is the surface located in the direction opposite to the bending direction of the segment, and wherein, the second surface of the first electrode is the surface located in the bending direction of the segment.

11. The electrode assembly according to claim 8, Among them, In the region where the grooved valley of the insulating layer is formed, the edge cutting surface of the laminate including the first insulating layer, the segment and the second insulating layer is inclined such that the area of the second insulating layer is larger than the area of the first insulating layer.

12. A battery, the battery comprising: The electrode assembly according to any one of claims 1 to 11; and A housing configured to accommodate the electrode assembly.

13. A battery pack, the battery pack comprising the battery according to claim 12.

14. A vehicle, the vehicle comprising the battery pack according to claim 13.

15. A method for manufacturing an electrode assembly, the method for manufacturing an electrode assembly comprising the following steps: An electrode preparation step of preparing a first electrode having insulating layers provided on both of its surfaces; A segment forming step of forming a plurality of segments by irradiating a laser on the first surface of the first electrode to groove the uncoated portion of the first electrode; A laminate preparation step of forming a laminate including the first electrode; and A winding step of winding the laminate to form an electrode assembly.

16. The method for manufacturing an electrode assembly according to claim 15, the method for manufacturing an electrode assembly further comprising the following steps: Orienting the first surface of the first electrode on which the laser irradiation is performed toward the outside of the electrode assembly.

17. The method for manufacturing an electrode assembly according to claim 15, the method for manufacturing an electrode assembly further comprising the following steps: Bending the plurality of segments along the radial direction of the electrode assembly.

18. The method for manufacturing an electrode assembly according to claim 17, Among them, The winding step includes the following steps: positioning the first surface of the first electrode on which the laser irradiation is performed in the direction opposite to the bending direction of the segment.

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