Battery cell, and battery pack and vehicle including same

Abstract

A battery cell according to an embodiment of the present invention includes: a battery can including a crimping portion; an electrode assembly disposed in the battery can; a first current collector plate in contact with the electrode assembly; and a sealing gasket disposed in the crimping portion, wherein the first current collector plate includes a battery can coupling portion disposed in the crimping portion and electrically connected to the battery can, and the battery can coupling portion includes an inclined surface in contact with the sealing gasket.

Description

Battery cells, battery packs including the same, and automobiles

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

[0002]

[0003] With the recent advancements in electric vehicles, portable electronic devices, and energy storage systems, the demand for high-capacity, high-output, and long-life secondary battery cells (hereinafter referred to as battery cells) is rapidly increasing.

[0004] A battery cell consists of an electrode assembly, an electrolyte, a battery can, and other components. The electrode assembly is composed of a positive electrode, a negative electrode, and a separator that separates them, and stores and releases energy through electrochemical reactions within the battery cell.

[0005] However, existing battery structures suffer from performance degradation and manufacturing process inefficiencies because the electrode assembly and current collection structure are not sufficiently optimized to minimize internal resistance and stably output high current. Furthermore, the incomplete coupling structure between the battery can and the current collection plate reduces electrical connection reliability, and overheating issues may arise due to increased internal resistance during prolonged use.

[0006] Therefore, structural improvements are required for efficient power transfer and reduction of internal resistance of the battery, and in particular, technology is needed to extend battery life and improve performance by optimizing the combined structure of the battery can and the current collector plate.

[0007]

[0008] The present invention has been devised to solve the aforementioned problems, and the present invention aims to provide a battery cell that reduces internal resistance and improves power transfer efficiency by optimizing the electrical connection structure of the battery can and the electrode assembly in order to solve the aforementioned problems.

[0009] Another objective of the present invention is to provide a battery cell that improves electrical reliability by strengthening the bonding force between the battery can and the current collector plate, and maintains stable performance even during long-term use.

[0010] In addition, another objective of the present invention is to provide a battery cell structure that can improve ease of assembly and reduce manufacturing costs during the battery manufacturing process.

[0011]

[0012] A battery cell according to the present invention comprises: a battery can including a crimping portion; an electrode assembly disposed in the battery can; a first current collector plate in contact with the electrode assembly; and a sealing gasket disposed in the crimping portion; wherein the first current collector plate includes a battery can coupling portion disposed in the crimping portion and electrically connected to the battery can, and the battery can coupling portion includes an inclined surface in contact with the sealing gasket.

[0013] The thickness of the battery can coupling portion above decreases from the inner side to the outer side of the first current collector plate.

[0014] The battery can coupling portion includes a bottom surface and an upper surface spaced apart from the bottom surface in the thickness direction of the battery can coupling portion, and the inclined surface connects the bottom surface and the upper surface.

[0015] The above inclined surface becomes closer to the bottom surface as it moves from the inner side to the outer side of the first collector plate.

[0016] The first current collector plate includes a body portion that contacts the electrode assembly, and the battery can coupling portion is provided in plurality, and the plurality of battery can coupling portions are spaced apart from each other along the edge of the body portion.

[0017] The first current collector plate includes a body portion that contacts the electrode assembly and a connecting portion that connects the body portion and the battery can coupling portion, and there is a bent structure between the body portion and the connecting portion.

[0018] The battery can includes a beading portion connected to the crimping portion, the crimping portion is positioned closer to the end of the battery can than the beading portion, and the battery can coupling portion contacts the support surface of the beading portion.

[0019] The battery can coupling portion comprises a bottom surface and an upper surface spaced apart from the bottom surface in the thickness direction of the battery can coupling portion, and the bottom surface contacts the support surface of the beading portion.

[0020] The first current collector plate includes a body portion that contacts the electrode assembly, and a tab coupling portion that is coupled to the electrode assembly is disposed in the edge region of the body portion.

[0021] It includes a connecting part that connects the body part and the battery can connecting part, and the connecting part and the tab connecting part are arranged adjacently.

[0022] The above-mentioned tab coupling portions are arranged in multiple numbers, and the multiple tab coupling portions are arranged radially with the body portion at the center.

[0023]

[0024] According to the present invention, the battery cell according to the present invention optimizes the electrical connection between the battery can and the electrode assembly to reduce internal resistance and improve power transfer efficiency. This improves the output characteristics of the battery and increases charge / discharge efficiency.

[0025] In addition, mechanical strength and electrical reliability are enhanced by improving the combined structure of the battery can and the current collector plate. In particular, by suppressing the increase in internal resistance over a long period during battery use, heat generation is minimized and battery life can be extended.

[0026] Furthermore, the battery cell structure of the present invention can increase precision in the assembly process and reduce the defect rate that may occur during assembly. Accordingly, the effects of reducing manufacturing costs and improving production efficiency can be expected.

[0027] In conclusion, the present invention provides the advantage of maximizing battery performance in various applications requiring high output and long lifespan, and ensuring a stable power supply.

[0028] However, the effects according to the present invention are not limited to those described above, and other unmentioned technical effects will be clearly understood by a person skilled in the art from the description of the invention below.

[0029]

[0030] FIG. 1 illustrates a battery cell according to an embodiment of the present invention.

[0031] Figure 2 is an obliquely illustrated cross-section of the battery cell of Figure 1.

[0032] Figure 3 is a front view of the battery cell of Figure 2 with some of the cross-section omitted.

[0033] FIG. 4 illustrates a first current collector plate according to an embodiment of the present invention.

[0034] FIG. 5 illustrates a cross-section of the battery cell coupling portion of the first current collector plate according to an embodiment of the present invention.

[0035] Figure 6 illustrates A of Figure 3.

[0036] FIG. 7 is a schematic diagram illustrating a battery pack according to an embodiment of the present invention.

[0037] FIG. 8 is a schematic diagram illustrating an automobile according to an embodiment of the present invention.

[0038]

[0039] Hereinafter, specific details for implementing the present invention will be described in detail with reference to the attached drawings. However, in the following description, specific descriptions regarding widely known functions or configurations will be omitted if there is a risk of unnecessarily obscuring the essence of the present invention.

[0040] In the attached drawings, identical or corresponding components may be assigned the same reference numerals. Additionally, in the description of the following embodiments, the description of identical or corresponding components may be omitted. However, even if a description of a component is omitted, it is not intended that such component is not included in any embodiment.

[0041] The terms used in this specification will be briefly explained, and the disclosed embodiments will be described in detail. The terms used in this specification have been selected to be as generally used as possible, taking into account their functions in the present invention; however, these terms may vary depending on the intent of those skilled in the relevant field, case law, the emergence of new technologies, etc. Additionally, in specific cases, terms may be arbitrarily selected by the applicant, and in such cases, their meanings will be described in detail in the relevant description of the invention. Therefore, the terms used in this invention should be defined not merely by their names, but based on their meanings and the overall content of the present invention.

[0042] In this specification, singular expressions may include plural expressions unless the context clearly specifies them as singular. Additionally, plural expressions may include singular expressions unless the context clearly specifies them as plural. Throughout the specification, when a part is described as including a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0043] In this specification, terms such as “comprising,” “comprising,” etc., may indicate the presence of features, steps, operations, elements, and / or components, but do not exclude the addition of one or more other functions, steps, operations, elements, components, and / or combinations thereof.

[0044] In this specification, where a specific component is described as being "coupled," "combined," "connected," or "reacting" to any other component, the specific component may be directly coupled, combined, and / or connected, or reacting to the other component, but is not limited thereto. For example, one or more intermediate components may exist between the specific component and the other component. Additionally, in the present invention, "and / or" may include each of the one or more listed items or a combination of at least some of the one or more items.

[0045] In this specification, terms such as "first," "second," etc., are used to distinguish a specific component from another component, and the components described above are not limited by these terms. For example, the "first" component may be an element of the same or similar form as the "second" component.

[0046]

[0047] FIG. 1 illustrates a battery cell according to an embodiment of the present invention, FIG. 2 illustrates a cross-section of the battery cell of FIG. 1 at an angle, and FIG. 3 illustrates a cross-section of the battery cell of FIG. 2 partially omitted and shown from the front.

[0048] Referring to FIGS. 1 to 3, a battery cell (1) according to an embodiment of the present invention may include a battery can (20), an electrode assembly (30), a first current collector plate (40), a cap (50), a terminal (60), and a sealing gasket (G1). Additionally, the battery cell (1) may further include a second current collector plate (70) and / or an insulator (80). The electrode assembly (30) may include a first electrode tab (31) and a second electrode tab (32).

[0049] The electrode assembly (30) may include a first electrode having a first polarity, a second electrode having a second polarity, and a separator disposed between the first electrode and the second electrode. The first electrode may be a negative electrode or a positive electrode, and the second electrode may have a polarity opposite to that of the first electrode.

[0050] The first electrode, the separator, the second electrode, and the separator can be sequentially stacked and wound. That is, the electrode assembly (30) may be a jelly-roll type electrode assembly. Accordingly, the electrode assembly (30) may have a winding center hole (H1) that extends approximately parallel to the height direction of the battery cell (1).

[0051]

[0052] The first electrode includes a first electrode current collector and a first electrode active material applied to one or both sides of the first electrode current collector. A first electrode uncoated portion is disposed on one side of the first electrode current collector.

[0053] The first electrode non-existent portion may refer to an area of ​​the first electrode current collector where the first electrode active material is not applied. When the first electrode is in an unfolded state, the first electrode non-existent portion extends along the length direction of the unfolded first electrode. The first electrode non-existent portion may function as a first electrode tab (31).

[0054] Based on FIG. 3, the first electrode tab (31) is provided in the upper height direction of the electrode assembly (30) housed in the battery can (20). The first electrode tab (31) may be, for example, a negative electrode tab.

[0055] The second electrode includes a second electrode current collector and a second electrode active material applied to one or both sides of the second electrode current collector. A second electrode uncoated portion is disposed on one side of the second electrode current collector.

[0056] The second electrode non-existent portion may refer to an area of ​​the second electrode current collector where the second electrode active material is not applied. When the second electrode is in an unfolded state, the second electrode non-existent portion extends along the length direction of the unfolded second electrode. The second electrode non-existent portion may function as a second electrode tab (32).

[0057] Based on FIG. 3, the second electrode tab (32) is provided in the lower height direction of the electrode assembly (30) housed in the battery can (20). The first electrode tab (31) may be, for example, a negative electrode tab.

[0058] That is, the first electrode tab (31) and the second electrode tab (32) can be arranged in opposite directions along the height direction of the battery cell (1).

[0059]

[0060] The battery can (20) may be a hollow cylindrical structure. The battery can (20) may be formed of a conductive metal. An electrode assembly (30) may be accommodated in the battery can (20). An electrolyte may be accommodated in the battery can (20).

[0061]

[0062] The battery can (20) is electrically connected to the electrode assembly (30). The battery can (20) is connected to the first electrode tab (31) of the electrode assembly (30). Thus, the battery can (20) has the same electrical polarity as the first electrode tab (31).

[0063]

[0064] A beading portion (21) that is bent toward the inside of the battery can (20) may be disposed on one side of the battery can (20). A crimping portion (22) that is connected to the beading portion (21) and disposed toward the end of the battery can (20) rather than the beading portion (21) may be included on one side of the battery can (20).

[0065] The beading portion (21) may be in the form of a perimeter of the outer surface of the battery can (20) pressed in to a predetermined depth. The inner diameter of the battery can (20) in the area where the beading portion (21) is formed may be smaller than the diameter of the electrode assembly (30).

[0066]

[0067] The beading portion (21) provides a support surface (210) on which a cap (50) can be seated. Additionally, the beading portion (21) can provide a support surface (210) on which a battery can coupling portion (440) of the first current collector plate (40), which will be described later, can be seated and coupled. At least a portion of the battery can coupling portion (440) of the first current collector plate (40) can be seated on the support surface (210) of the beading portion (21).

[0068]

[0069] The crimping portion (22) may be formed adjacent to the beading portion (21). The crimping portion (22) may be positioned relatively outward in the height direction of the battery cell compared to the beading portion (21). The crimping portion (22) may have a structure that is extended and bent to wrap around the perimeter of the edge of the cap (50) positioned on top of the beading portion (21). Due to the shape of this crimping portion (22), the cap (50) may be fixed on the beading portion (21).

[0070]

[0071] FIG. 4 illustrates a first current collector according to an embodiment of the present invention, and FIG. 5 illustrates a cross-section of a battery cell coupling portion of the first current collector according to an embodiment of the present invention.

[0072] Referring to FIGS. 4 and FIGS. 5, a first current collector plate (40) according to one embodiment of the present invention will be described.

[0073]

[0074] *65 The first current collector plate (40) can be placed inside the battery can (20) and electrically connected to the electrode assembly (30). Additionally, the first current collector plate (40) can be electrically connected to the battery can (20). That is, the first current collector plate (40) can electrically connect the battery can (20) and the electrode assembly (30).

[0075] The first collector plate (40) may include a body part (410), a tab connecting part (420), a connecting part (430), and a battery can connecting part (440).

[0076] The body portion (410) may include a first current collector hole (411). The body portion (410) may have a ring structure. The first current collector hole (411) may be positioned at a location corresponding to a winding hole (H1) formed in the center of the electrode assembly (30).

[0077] One side of the body portion (410) may be positioned toward the electrode assembly (30). One side of the body portion (410) may come into contact with the electrode assembly (30). Referring again to FIG. 3, one side of the body portion (410) may come into contact with the first electrode tab (31) of the electrode assembly (30). That is, one side of the body portion (410) may be electrically connected to the negative electrode of the electrode assembly (30).

[0078]

[0079] The tab connecting portion (420) may be positioned in the edge region of the body portion (410). The tab connecting portion (420) may extend radially outward from the edge region of the body portion (410). The tab connecting portion (420) may be positioned in multiple numbers. Multiple tab connecting portions (420) may be positioned spaced apart from each other along the circumferential direction of the body portion (410). The tab connecting portion (420) may be connected to the electrode assembly (30). One surface of the tab connecting portion (420) may be in contact with the first electrode tab (31) of the electrode assembly (30). The tab connecting portion (420) and the first electrode tab (31) may be connected through welding.

[0080]

[0081] A connecting portion (430) may be positioned between the body portion (410) and the battery can coupling portion (440). The connecting portion (430) may be coupled to the body portion (410) and the battery can coupling portion (440). The connecting portion (430) may electrically connect the body portion (410) and the battery can coupling portion (440). The connecting portion (430) may extend from the body portion (410). The battery can coupling portion (440) may be a structure extending from the connecting portion (430). A bent structure may be positioned between one side of the connecting portion (430) and the body portion (410). A bent structure may be positioned between the other side of the connecting portion (430) and the battery can coupling portion (440).

[0082]

[0083] A plurality of battery can coupling portions (440) may be provided. A plurality of battery can coupling portions (440) may be arranged radially with the body portion (410) at the center. A plurality of battery can coupling portions (440) may be arranged spaced apart from each other along the edge of the body portion (410). One of the plurality of battery can coupling portions (440) may be positioned between two tab coupling portions (420). That is, a battery can coupling portion (440) may be arranged adjacent to a tab coupling portion (420).

[0084] The thickness of the battery can coupling portion (440) can be varied sequentially. That is, at least one surface of the battery can coupling portion (440) can be positioned at an angle. Specifically, the battery can coupling portion (440) may include a bottom surface (441), a top surface (442), and an angled surface (443).

[0085] The bottom surface (441) may be a surface that contacts the support surface (210) of the beading portion (21). The top surface (442) may be a surface spaced apart from the bottom surface (441) in the thickness direction of the battery can coupling portion (440). The inclined surface (443) may be connected to the top surface (442). The inclined surface (443) may be connected to the bottom surface (441). The width (d2) of the top surface may be smaller than the width (d1) of the bottom surface.

[0086] The inclined surface (443) may become closer to the bottom surface (441) as it moves radially outward from the first collector plate (40). Accordingly, the thickness (d3) of the battery can connection portion may become thinner as it moves from the inside to the outside of the first collector plate (40). Additionally, the thickness (d3) of the battery can connection portion may become smaller as it moves from the inside to the outside of the battery can (20).

[0087]

[0088] FIG. 6 illustrates A of FIG. 3. With reference to FIG. 3 and FIG. 6, the coupling structure of the battery can coupling part (440) according to the present invention will be explained.

[0089] A sealing gasket (G1), a cap (50), and a battery can coupling part (440) may be disposed on the inner side of the crimping part (22). Specifically, the support surface (210) of the beading part (21), the battery can coupling part (440), and the sealing gasket (G1) may form a sandwich structure that is compressed by the crimping part (22).

[0090] The bottom surface (441) of the battery can coupling part (440) may face the support surface (210) of the beading part (21), and the inclined surface (443) of the battery can coupling part (440) may be positioned in contact with the sealing gasket (G1). The sealing gasket (G1) may be pressed by the crimping part (22) to be in close contact with the inclined surface (443) of the battery can coupling part (440).

[0091] The bottom surface (441) and the top surface (442) of the battery can coupling part (440) have a step difference, and since the step difference between the bottom surface (441) and the top surface (442) of the battery can coupling part (440) gradually changes through the inclined surface (443), it prevents the occurrence of a gap between the sealing gasket (G1) and the battery can coupling part (440), thereby having the effect of the sealing gasket (G1) and the battery can coupling part (440) being in close contact.

[0092]

[0093] FIG. 7 is a schematic diagram illustrating a battery pack according to an embodiment of the present invention. Referring to FIG. 7, the battery pack (3) according to an embodiment of the present invention may include a battery cell (1) and a housing (2) according to an embodiment of the present invention. In the drawings of the present invention, components such as a busbar for electrical connection, a cooling unit, and terminals are omitted for convenience of drawing.

[0094] FIG. 8 is a schematic diagram illustrating an automobile according to an embodiment of the present invention. Referring to FIG. 8, the automobile (5) according to an embodiment of the present invention may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle using a motor as a power device, and includes a battery pack (3) according to an embodiment of the present invention. The automobile (5) includes a four-wheeled vehicle and a two-wheeled vehicle. The automobile (5) may operate by receiving power from a battery pack (3) according to an embodiment of the present invention.

[0095]

[0096] Although the present invention has been described in relation to some embodiments, various modifications and changes may be made without departing from the scope of the invention as understood by a person skilled in the art to which the invention pertains. Furthermore, such modifications and changes should be considered to fall within the scope of the claims appended to this specification.

Claims

1. A battery can including a crimping section; Electrode assembly disposed in the battery can above; A first current collector plate in contact with the electrode assembly above; and A sealing gasket disposed in the above-mentioned crimping portion; comprising The first current collector plate includes a battery can coupling portion disposed in the crimping portion and electrically connected to the battery can, and The battery cell having an inclined surface that contacts the sealing gasket, wherein the battery can coupling portion described above is a battery cell.

2. In Paragraph 1, The thickness of the battery can coupling portion above is a battery cell that decreases from the inner side to the outer side of the first current collector plate.

3. In Paragraph 1, The battery can coupling part above is, It includes a bottom surface and an upper surface spaced apart from the bottom surface in the thickness direction of the battery can coupling portion, The above inclined surface is a battery cell connecting the bottom surface and the top surface.

4. In Paragraph 3, The above inclined surface is a battery cell in which the distance from the bottom surface decreases as it moves from the inner side to the outer side of the first current collector plate.

5. In Paragraph 1, The first current collector plate includes a body portion that contacts the electrode assembly, and The above battery can coupling part is provided in multiple numbers, and A plurality of the above-mentioned battery can coupling portions are arranged spaced apart from each other along the edge of the body portion, forming a battery cell.

6. In Paragraph 1, The first current collector plate includes a body portion that contacts the electrode assembly and a connecting portion that connects the body portion and the battery can coupling portion. A battery cell having a bent structure between the body part and the connecting part.

7. In Paragraph 1, The above battery can includes a beading portion connected to the crimping portion, and The above crimping portion is positioned closer to the end of the battery can than the above beading portion, and A battery cell in which the battery can coupling part contacts the support surface of the above-mentioned beading part.

8. In Paragraph 7, The battery can coupling part above is, It includes a bottom surface and an upper surface spaced apart from the bottom surface in the thickness direction of the battery can coupling portion, The above bottom surface is a battery cell that contacts the support surface of the above beading portion.

9. In Paragraph 1, The first current collector plate includes a body portion that contacts the electrode assembly, and A battery cell having a tab coupling portion disposed in the edge region of the body portion that is coupled with the electrode assembly.

10. In Paragraph 9, It includes a connecting part that connects the above body part and the above battery can coupling part, and The above connecting portion and the above tab coupling portion are adjacent to each other battery cells.

11. In Paragraph 9, The above tab coupling portions are arranged in multiple numbers, and The above plurality of tab couplings are battery cells arranged radially with the body portion at the center.

12. A battery pack comprising a battery cell according to any one of paragraphs 1 through 11.

13. An automobile including a battery pack pursuant to Paragraph 12.