Battery, battery pack including the same, and motor vehicle

Abstract

The present invention discloses a battery having a structure in which a protective member is applied between an electrode assembly and a beading portion. A battery according to an aspect of the present invention includes an electrode assembly, a battery housing including a beading portion formed with an opening portion on one side and accommodating the electrode assembly through the opening portion, and formed by press-fitting an outer peripheral edge from the side of the opening portion, a top cap covering the opening portion, and a first protective member interposed between the beading portion and the electrode assembly.

Description

Technical Field

[0001] The present invention relates to a battery, a battery pack, and an automobile including the same, having a structure in which a protective member is applied between an electrode assembly and a welding portion.

[0002] This application claims priority based on Korean Patent Application No. 10-2022-0089219 filed on July 19, 2022, and all of the contents disclosed in the specification and drawings of the application are incorporated into this application.

Background Art

[0003] Batteries with high applicability to product groups and having electrical characteristics such as high energy density are widely applied not only to portable devices but also to electric vehicles (EVs) and hybrid electric vehicles (HEVs) driven by electric drive sources.

[0004] Such batteries are attracting attention as a new energy source for environmental friendliness and energy efficiency improvement because they have not only the primary merit of significantly reducing the use of fossil fuels but also the merit of generating no by-products associated with energy use.

[0005] Currently widely used battery types include lithium-ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel metal hydride batteries, nickel zinc batteries, etc. The operating voltage of such a single battery cell is about 2.5V to 4.5V. Therefore, when a higher output voltage is required, a plurality of batteries are connected in series to form a battery pack. Also, depending on the charge and discharge capacity required for the battery pack, a plurality of batteries may be connected in parallel to form a battery pack. Therefore, the number of batteries included in the battery pack and the form of electrical connection can be variously set according to the required output voltage and / or charge and discharge capacity.

[0006] Recently, in order to achieve a high energy density and cost reduction of battery packs, development has been progressing in the direction of increasing the cell size.

[0007] In order to improve the energy density, it is necessary to maximize the size of the electrode assembly to maximize the capacity. For this purpose, it is necessary to maximize the internal space by making the thickness of the battery housing as thin as possible.

[0008] However, if the thickness of the battery housing is made too thin, it will be disadvantageous in terms of the durability of the battery housing, and there is a possibility that the battery housing will break or tear at the thinned part.

[0009] In particular, the beading portion formed by press-fitting the outer peripheral edge of the battery housing for preventing the separation of the electrode assembly from the open portion side of the battery housing is a deformed portion once, so it may become more vulnerable. In addition, due to the stretching of the battery housing by press-fitting, a part of the beading portion forming part in the battery housing may be thinner than the surrounding area.

[0010] Such a beading portion has a problem that when a thermal event occurs inside the battery, it may be damaged by fire and / or gas, or pinholes may occur.

[0011] Therefore, in order to solve such problems, it is necessary to protect the beading portion from the internal fire and / or gas.

Summary of the Invention

Problems to be Solved by the Invention

[0012] The present invention has been made in view of the above problems, and its object is to protect the beading portion, which may be structurally vulnerable, from internal fire and / or gas, and prevent deformation and damage of the beading portion.

[0013] In another aspect, another object of the present invention is to prevent the formation of pinholes in the beading portion and prevent structural collapse when a flame occurs inside.

[0014] In still another aspect, still another object of the present invention is to protect the beading portion without blocking the flame and gas discharge passages at the center of the electrode assembly when a flame occurs inside.

[0015] However, the technical problems to be solved by the present invention are not limited to the above-described problems, and other problems not mentioned should be clearly understood by those skilled in the art from the description of the invention described below.

Means for Solving the Problems

[0016] A battery according to an embodiment of the present invention includes an electrode assembly, a battery housing including a beading portion formed with an opening portion on one side and accommodating the electrode assembly through the opening portion, and formed by press-fitting the outer peripheral edge from the side of the opening portion, a top cap covering the opening portion, and a first protective member interposed between the beading portion and the electrode assembly.

[0017] The first protective member may include a material having heat resistance.

[0018] The outer diameter of the first protective member may be substantially the same as the inner diameter of the battery housing.

[0019] The first protective member may be provided with a central hole.

[0020] The first protective member may have a width corresponding to the depth to which the beading portion is press-fitted.

[0021] The first protective member may extend along the circumferential direction of the battery housing.

[0022] The diameter of the central hole in the first protective member may be substantially the same as the inner diameter of the battery housing in the region where the beading portion is formed.

[0023] A first current collector including a first coupling portion that is electrically coupled to the electrode assembly on the side of the open portion and a housing coupling portion that is electrically coupled to the battery housing may be included.

[0024] The first coupling portion may abut against the first protective member on one surface of the electrode assembly.

[0025] The first current collector may be integrally formed with the first protective member.

[0026] The battery pack according to the present invention may include the battery according to the present invention.

[0027] The automobile according to the present invention may include the battery pack according to the present invention.

Advantages of the Invention

[0028] According to one aspect of the present invention, the first protective member can protect the beading portion. It is possible to protect the beading portion, which may be structurally vulnerable, from the flame and / or gas inside the battery, and prevent deformation and damage of the beading portion. When a flame occurs inside the battery, the first protective member having heat resistance can prevent pinholes from being formed in the beading portion and prevent structural collapse. Also, by using the substantially donut-shaped first protective member, it is possible to protect the beading portion without blocking the flame and gas discharge passage at the center of the electrode assembly. Ultimately, the stability of the battery can be significantly improved.

[0029] According to another aspect of the present invention, the portion of the beading part protected by the second protective member is the portion that is most deeply press-fitted toward the winding shaft and corresponds to the portion where the thickness becomes the thinnest due to stretching. Therefore, the second protective member can more effectively protect the beading part. When a flame occurs inside the battery, the second protective member having heat resistance can prevent pinholes from being formed on the innermost surface of the beading part and prevent structural collapse. In addition, the second protective member can guide the movement path of the gas and / or flame. The gas and / or flame whose movement direction is primarily restricted by the first protective member is guided to the top cap through the second protective member. As a result, the gas and / or flame can be effectively discharged from the vent part of the top cap described later.

Brief Description of the Drawings

[0030]

Figure 1

Figure 2

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Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

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Figure 12

Embodiments for Carrying Out the Invention

[0031] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further interpret the technical idea of the present invention together with the detailed description of the invention to be described later. Therefore, the present invention is not to be construed as being limited only to the matters described in such drawings. The same reference numerals refer to the same components. Also, in the drawings, the thickness, ratio, and dimensions of the components may be exaggerated for the purpose of effectively explaining the technical content.

[0032] The terms and words used in this specification and the claims are not to be construed as being limited to their ordinary or dictionary meanings. The inventor interprets them in accordance with the meaning and concept corresponding to the technical idea of the present invention in accordance with the principle that the inventor can appropriately define the concept of the terms in order to explain the invention in the best way.

[0033] In this specification, terms indicating directions such as up, down, left, right, front, and back are used, but these terms are merely for convenience of explanation and may vary depending on the position of the object to be described or the position of the observer, which is self-evident to those skilled in the art of the present invention.

[0034] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. At the time of this application, there can be various equivalent and modified embodiments that can replace these.

[0035] FIG. 1 is a diagram showing electrodes 110 and 120 included in battery 10 according to an embodiment of the present invention. FIG. 2 is a diagram showing a laminate 100' of electrode assembly 100 included in battery 10 according to an embodiment of the present invention. FIG. 3 is a diagram showing battery 10 according to an embodiment of the present invention. FIG. 4 is a diagram showing a cross-section of battery 10 according to an embodiment of the present invention. FIG. 5 is a diagram showing a first protective member 400 included in battery 10 according to an embodiment of the present invention.

[0036] Referring to FIGS. 1 to 5, battery 10 according to the present invention may include an electrode assembly 100, a battery housing 200, a top cap 300, and a first protective member 400.

[0037] The electrode assembly 100 may be formed by winding a laminate 100' including a first electrode 110, a second electrode 120, and a separator (separating film) 130 around a winding axis.

[0038] The electrode assembly 100 includes a first electrode 110 including a first non-coated portion 111 where the active material layer is not coated along the winding direction, a second electrode 120 including a second non-coated portion 121 where the active material layer is not coated along the winding direction, and a separator 130 interposed therebetween. The laminate 100' may be wound around a common winding axis to form a core and an outer peripheral surface.

[0039] The first electrode 110 may include a first electrode plate and a first electrode active material layer 112 formed by applying a first electrode active material on at least one surface of the first electrode plate. The second electrode 120 may include a second electrode plate and a second active material layer 122 formed by applying a second electrode active material on at least one surface of the second electrode plate. The first electrode 110 may include a first plain portion 111 on which no positive electrode active material or negative electrode active material is applied to the electrode plate. The second electrode 120 may include a second plain portion 121 on which no positive electrode active material or negative electrode active material is applied to the electrode plate. For example, the first plain portion 111 may be provided at the upper end of the electrode assembly 100, and the second plain portion 121 may be provided at the lower end of the electrode assembly 100. At least a part of the first plain portion 111 may function as a first electrode tab, and at least a part of the second plain portion 121 may function as a second electrode tab. On the other hand, in the present invention, the electrode tab is not limited to being at least a part of the plain portion. That is, the electrode tab may be separately provided and coupled to the plain portion.

[0040] The battery housing 200 may have an opening formed on one side. The battery housing 200 may accommodate the electrode assembly 100 through the opening. The battery housing 200 may have the polarity of the first electrode. The battery housing 200 may be made of a conductive metal material. The battery housing 200 may also accommodate the electrolyte together through the opening.

[0041] The battery housing 200 may include a beading portion 210. The beading portion 210 is formed at an end adjacent to the opening and may be press-fitted inward. The beading portion 210 may have a form formed by press-fitting the outer peripheral edge of the battery housing 200 to a predetermined depth. The beading portion 210 may be formed on the upper part of the electrode assembly 100. The beading portion 210 can serve to prevent the electrode assembly 100 from moving in the height direction.

[0042] The top cap 300 can be configured to cover the opening portion. The top cap 300 can be configured to have no polarity. The top cap 300 can be a metallic material having conductivity.

[0043] The first protective member 400 can be interposed between the beading portion 210 and the electrode assembly 100. The outer diameter of the first protective member 400 can be substantially the same as the inner diameter of the battery housing 200. The first protective member 400 can be fitted inside the battery housing 200. The first protective member 400 can be interposed between at least a part of the region corresponding to the beading portion 210 on one surface of the electrode assembly 100 and the beading portion.

[0044] The first protective member 400 can include a central hole. The diameter of the central hole of the first protective member 400 can be substantially the same as the inner diameter of the battery housing 200 in the region where the beading portion 210 is formed. The first protective member 400 can have a width corresponding to the depth to which the beading portion 210 is press-fitted. That is, the diameter of the central hole can be approximately the same as the length obtained by subtracting twice the length to which the beading portion 210 in the battery housing 200 is press-fitted from the outer diameter of the first protective member 400 of the battery 10. The first protective member 400 can be substantially donut-shaped. However, the present invention does not exclude the case where the width of the first protective member 400 is larger than the depth to which the beading portion 210 is press-fitted. The first protective member 400 may extend along the circumferential direction of the battery housing 200.

[0045] The first protective member 400 can include a material having heat resistance.

[0046] Since the beading portion 210 is a deformed part by press-fitting, it is vulnerable to deformation. In the formation part of the beading portion 210 by press-fitting, the battery housing 200 extends, so the thickness of the battery housing 200 may be thinner than that of the peripheral part. Such a beading portion 210 has a problem that when a thermal event occurs inside the battery 10, it may be damaged by a flame and / or gas, or pinholes may occur.

[0047] FIG. 6 is a diagram showing the flow of gas and flame inside the battery 10 according to an embodiment of the present invention.

[0048] Referring to FIG. 6 to explain such a structure of the present invention, the first protective member 400 can protect the beading portion 210. It is possible to protect the beading portion 210, which may be structurally fragile, from the flame and / or gas inside the battery 10, and prevent deformation and damage of the beading portion 210. When a flame occurs inside the battery 10, the first protective member 400 having heat resistance can prevent pinholes from being formed in the beading portion 210 and prevent structural collapse. Also, by using the substantially donut-shaped first protective member 400, the beading portion 210 can be protected while not blocking the flame and gas discharge passage at the center of the electrode assembly 100. Finally, the stability of the battery 10 can be significantly improved.

[0049] FIG. 7 is a diagram showing the battery 10 according to another embodiment of the present invention. FIG. 8 is a diagram showing the first protective member 400 included in the battery 10 according to another embodiment of the present invention.

[0050] Referring to FIGS. 7 and 8, the battery 10 according to the present invention may include a second protective member 410.

[0051] The second protective member 410 may be formed along the inner surface of the beading portion 210 closest to the winding shaft. The second protective member 410 may extend in the height direction of the battery 10 by substantially the same height as the height of the beading portion 210. The second protective member 410 may extend along the circumferential direction of the battery housing 200. The second protective member 410 may have a diameter substantially the same as the inner diameter of the battery housing 200 in the region where the beading portion 210 is formed. The second protective member 410 may be fitted into the deepest press-fitted portion of the beading portion 210 toward the winding shaft.

[0052] The second protective member 410 may have heat resistance.

[0053] The second protective member 410 may be connected to the first protective member 400. The second protective member 410 may be integrally formed with the first protective member 400. The portion where the second protective member 410 and the first protective member 400 are connected may have a curvature substantially corresponding to the curvature of the beading portion 210.

[0054] According to such a configuration of the present invention, the portion of the beading portion 210 protected by the second protective member 410 is the deepest press-fitted portion toward the winding shaft and corresponds to the portion where the thickness becomes the thinnest due to stretching. Therefore, the second protective member 410 can more effectively protect the beading portion 210. When a flame occurs inside the battery 10, the heat-resistant second protective member 410 can prevent pinholes from being formed on the innermost surface of the beading portion 210 and prevent structural collapse. In addition, the second protective member 410 can guide the movement path of the gas and / or flame. The gas and / or flame whose movement direction is primarily restricted by the first protective member 400 is guided to the top cap 300 via the second protective member 410. As a result, the gas and / or flame can be effectively discharged from the vent portion 310 of the top cap 300 described later.

[0055] Returning to FIG. 4, the battery 10 may include the crimping portion 220 of the battery housing 200 and / or the vent portion 310 of the top cap 300 and / or the terminal 700 and / or the first current collector 500 and / or the second current collector 600 and / or the insulator 800 and / or the first gasket G1 and / or the second gasket G2.

[0056] The battery housing 200 may include a crimping portion 220. The crimping portion 220 may be formed on the upper part of the beading portion 210. The crimping portion 220 may have a bending shape that extends and bends so as to wrap around the edge region of the top cap 300. Due to the shape of such a crimping portion 220, the top cap 300 can be fixed on the beading portion 210.

[0057] The top cap 300 may include a vent portion 310 that is configured to be more fragile compared to the peripheral region. The vent portion 310 may have a thinner thickness compared to the peripheral region. The vent portion 310 may be formed by performing notching on one or both surfaces of the top cap 300 to partially reduce the thickness of the top cap 300.

[0058] The terminal 700 may be located on the opposite side of the open portion. The terminal 700 may be exposed to the outside of the battery housing 200 through a closed portion located on the opposite side of the open portion. The terminal 700 may have the polarity of the second electrode. The terminal 700 may penetrate through the substantially central portion of the lower surface of the battery housing 200.

[0059] The first current collector 500 may be located between the electrode assembly 100 and the top cap 300. The first current collector 500 may include a first coupling portion 510 that is electrically coupled to the electrode assembly 100. The first current collector 500 may include a housing coupling portion 520 that is electrically coupled to the battery housing 200 on the inner surface of the battery housing 200. The first current collector 500 may have the polarity of the first electrode.

[0060] The second current collector 600 can be positioned between the electrode assembly 100 and the terminal 700. The second current collector 600 may include a second coupling portion that is electrically coupled to the electrode assembly 100. The second current collector 600 may include a terminal 700 coupling portion that is electrically coupled to a portion of the terminal 700 that is inserted into the battery housing 200 and has a substantially flat surface. The second current collector 600 may have the polarity of the second electrode.

[0061] The insulator 800 can be positioned on the electrode assembly 100 for insulation between the battery housing 200 and the electrode assembly 100 on the closing portion side. The insulator 800 may be interposed between the closing portion of the battery housing 200 and the electrode assembly 100, or between the closing portion of the battery housing 200 and the second current collector 600. The insulator 800 may include, for example, a resin material having insulating properties. The insulator 800 may have a hole substantially at the center so that the terminal 700 can be electrically connected to the second current collector 600.

[0062] The first gasket G1 can be disposed between the top cap 300 and the battery housing 200. The first gasket G1 prevents the top cap 300 and the battery housing 200 from contacting each other.

[0063] The second gasket G2 can be disposed between the terminal 700 and the battery housing 200. The second gasket G2 prevents the terminal 700 and the battery housing 200 from contacting each other.

[0064] The first gasket G1 and the second gasket G2 can be made of a resin material having insulating and elastic properties.

[0065] FIG. 9 is a diagram showing the first current collector 500 and the first protective member 400 included in the battery 10 according to an embodiment of the present invention.

[0066] Referring to FIG. 9, the first protective member 400 may be in contact with the first coupling portion 510 on one surface of the electrode assembly 100. The first protective member 400 and the first current collector 500 may be integrally formed. According to the structure of the battery 10 as described above, since the first electrode 110, the first current collector 500, the first protective member 400, and the battery housing 200 have the same polarity, no abnormality occurs even if they are electrically connected. Therefore, the first current collector 500 and the first protective member 400 can be integrally formed to facilitate the production and assembly processes.

[0067] FIG. 10 is a diagram showing the first current collector 500, the first protective member 400, and the second protective member 410 included in the battery 10 according to another embodiment of the present invention.

[0068] Referring to FIG. 10, a groove may be provided in a portion of the second protective member 410 corresponding to the housing coupling portion 520. Since the housing coupling portion 520 extends from the electrode assembly 100 to the upper part of the bead portion 210, it is necessary to facilitate the movement in the height direction. Therefore, a substantially rectangular groove may be formed in a portion of the second protective member 410 corresponding to the housing coupling portion 520 to facilitate the movement of the housing coupling portion 520 in the height direction.

[0069] FIG. 11 is a diagram showing the battery pack 5 according to the present invention.

[0070] Referring to FIG. 11, the battery pack 5 according to the present invention may include the battery 10. In addition to the battery 10, the battery pack 5 may further include various other components, such as components of the battery pack 5 that are known at the time of filing of the present invention, such as a battery management system (BMS), a bus bar, a pack case, a relay, a current sensor, and the like.

[0071] FIG. 12 is a diagram showing the automobile 3 according to the present invention.

[0072] Referring to FIG. 12, the vehicle 3 according to the present invention may include a battery pack 5. The vehicle 3 may be a hybrid vehicle 3 or an electric vehicle 3. In addition to such a battery pack 5, the vehicle 3 according to the present invention may further include various other components included in the vehicle 3. For example, the vehicle 3 according to the present invention may further include, in addition to the battery pack 5 according to the present invention, a vehicle body, a motor, a control device such as an electronic control unit (ECU), and the like.

[0073] As described above, the present invention has been described mainly with reference to the preferred embodiments with reference to the accompanying drawings. However, it is obvious to those skilled in the art that many diverse and obvious modifications can be made without departing from the scope of the present invention from such a description. Therefore, the scope of the present invention should be interpreted by the claims described so as to include such many modified embodiments.

Explanation of Reference Numerals

[0074] 3 Vehicle 5 Battery pack 10 Battery 100 Electrode assembly 100’ Laminate 110 First electrode 111 First active material coating layer 112 First plain part 120 Second electrode 121 Second active material coating layer 122 Second plain part 130 Separator 200 Battery housing 210 Beading part 220 Crimping part 300 Top cap 310 Vent part 400 First protective member 410 Second protective member 500 First current collector 510 First coupling part 520 Housing joint 600 Second current collector 700 Terminal 800 Insulator G1 First gasket G2 Second gasket

Claims

1. An electrode assembly, A battery housing having an opening formed on one side and accommodating the electrode assembly through the opening, and including a beading portion formed by press-fitting the outer peripheral edge from the side of the opening, A top cap covering the opening, A first protective member interposed between the beading portion and the electrode assembly, A battery including the above.

2. The first protective member The battery according to claim 1, including a material having heat resistance.

3. The battery according to claim 1, wherein the outer diameter of the first protective member is the same as the inner diameter of the battery housing.

4. The first protective member The battery according to claim 1, having a central hole.

5. The first protective member The battery according to claim 4, having a width corresponding to the depth of press-fitting of the beading portion.

6. The first protective member The battery according to claim 1, extending along the circumferential direction of the battery housing.

7. The battery according to claim 4, wherein the diameter of the central hole in the first protective member is the same as the inner diameter of the battery housing in the region where the beading portion is formed.

8. The battery according to claim 1, including a first current collector including a first coupling portion that is electrically coupled to the electrode assembly on the side of the opening, and a housing coupling portion that is electrically coupled to the battery housing.

9. The first coupling portion The battery according to claim 8, abutting against the first protective member on one surface of the electrode assembly.

10. The first current collector The battery according to claim 8, integrally formed with the first protective member.

11. A battery pack including the battery according to any one of claims 1 to 10.

12. An automobile including the battery pack according to claim 11.

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