Battery cell

Abstract

The present invention relates to a battery cell and, more specifically, to a battery cell in which a lead protruding direction is changed so as to be able to reduce the length of a battery module, a bus bar can be freely designed due to the use of a larger space than in the conventional case, the width of a tab is maximized so as to be able to effectively achieve current density and heat generation, and the battery cell is more compact. And the welding area of the lead and the joint is enlarged compared with the conventional condition so as to realize stable connection. A battery cell according to the present invention may comprise: an electrode; electrode tabs provided on respective end portions of the electrodes in the first direction; and an electrode lead coupled to the electrode tab and formed to extend in a second direction perpendicular to the first direction.

Description

Technical Field

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit of the priority of Korean Patent Application No. 10 - 2022 - 0181850, filed on December 22, 2022, and Korean Patent Application No. 10 - 2023 - 0057923, filed on May 3, 2023, the entire disclosures of which are incorporated herein by reference.

[0004] The present invention relates to a battery cell, and more particularly, to a battery cell including an electrode, a lead, and a connector. Background Art

[0005] In recent years, due to the depletion of fossil fuels, rising energy prices, increased attention to environmental pollution, and the demand for eco - friendly alternative energy has become an indispensable factor in future life. Therefore, research on various power generation technologies such as solar energy, wind energy, and tidal energy is ongoing, and research on energy storage devices such as batteries for more effectively using the generated electric energy has also received much attention.

[0006] In addition, with the development of technology and the increasing demand for electronic mobile devices and electric vehicles using batteries, the demand for batteries as an energy source is also rapidly growing. Therefore, a great deal of research has been conducted on batteries that can meet various demands.

[0007] Batteries are receiving wide attention as an energy source in various products such as mobile devices and electric vehicles. In particular, secondary batteries are an excellent energy source that can replace the use of existing products using fossil fuels, and because secondary batteries do not generate by - products due to energy use, secondary batteries are receiving attention as an eco - friendly energy source.

[0008] Secondary batteries have received considerable attention as a power source for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug - in hybrid electric vehicles (PHEVs), the development of which is to solve limitations such as air pollution caused by existing gasoline and diesel vehicles using fossil fuels. In other words, secondary batteries are used in the form of a battery pack including a plurality of battery modules.

[0009] In a secondary battery, a lead connector is a connection terminal for electrically connecting the positive and negative electrodes in the secondary battery to the outside. A plurality of battery cells are stacked to form a battery module, and a positive connector connected to the positive electrode of the battery cell and a negative connector connected to the negative electrode are connected to a lead.

[0010] In the related art, the lead wires in a battery cell are designed to be horizontal with respect to the longitudinal direction of the battery cell. Therefore, the overall length becomes longer, and when the battery cells are arranged and used in a parallel structure, there is a problem of lead wire bending. In addition, the lead wires protruding in the longitudinal direction must be connected to the bus bar in the longitudinal direction of the module. However, there is a problem that the design of the bus bar having a structure according to the related art is limited. Summary of the Invention

[0011] Technical Problem

[0012] To solve the above problems, the present invention can reduce the length of the battery module by changing the protruding direction of the lead wires. In addition, the bus bar can be freely designed by using a space wider than the existing space. In addition, an object of the present invention is to provide a battery cell in which the width of the joint is maximized to effectively achieve current density and heat dissipation, and the welding area between the lead wire and the joint is enlarged compared to the existing welding area so that the lead wire and the joint are stably connected.

[0013] Technical Solution

[0014] A battery cell according to an embodiment of the present invention may include: an electrode, an electrode joint provided at each of both ends of the electrode in a first direction, and an electrode lead wire connected to the electrode joint and extending in a second direction perpendicular to the first direction.

[0015] The electrode joint may include a positive electrode joint provided at one end of the electrode and a negative electrode joint provided at the other end of the electrode, wherein, with respect to the second direction, each of the positive electrode joint and the negative electrode joint may have the same length as the electrode.

[0016] The length of each of the positive electrode joint and the negative electrode joint in the second direction may be greater than the length of each of the positive electrode joint and the negative electrode joint in the first direction.

[0017] The electrode lead wire may include a first lead wire provided at one end of the electrode and a second lead wire provided at the other end of the electrode, wherein the first lead wire and the second lead wire may extend in the same direction in the second direction.

[0018] The length of each of the first lead wire and the second lead wire in the second direction may be greater than the length of each of the first lead wire and the second lead wire in the first direction.

[0019] The first lead wire may include a first connection portion connected to the positive electrode joint, the second lead wire may include a second connection portion connected to the negative electrode joint, and with respect to the second direction, the length of the first connection portion and the length of the second connection portion may be the same as the length of each of the positive electrode joint and the negative electrode joint.

[0020] The battery cell may further include a battery case configured to accommodate the electrodes and the electrode connectors, wherein the first lead and the second lead may protrude from the battery case in a second direction.

[0021] The first lead and the second lead may protrude from the battery case in the same direction in the second direction.

[0022] The first lead and the second lead may have the same length protruding from the battery case.

[0023] With respect to the second direction, the edge on one side of the electrode lead and the edge on one side of the electrode connector may be arranged to correspond to each other.

[0024] Advantageous Effects

[0025] According to an embodiment of the present invention, the protruding direction of the leads can be changed to reduce the length of the battery module, the bus bar can be freely designed by using a space wider than the existing space, the width of the connector can be maximized to effectively achieve current density and heat dissipation, and the welding area between the lead and the connector can be enlarged compared with the existing welding area, so that the lead and the connector are stably connected. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the present invention, are used to further understand the technical spirit of the present invention. Therefore, the present invention should not be construed as being limited to the drawings.

[0027] Figure 1 is a front view of a battery cell according to Embodiment 1 of the present invention.

[0028] Figure 2 is an enlarged view illustrating the positive electrode connector and the first lead of the battery cell according to Embodiment 1 of the present invention.

[0029] Figure 3 is an enlarged view illustrating the negative electrode connector and the second lead of the battery cell according to Embodiment 1 of the present invention.

[0030] Figure 4 is a front view illustrating the electrodes and the electrode connectors of the battery cell according to Embodiment 1 of the present invention.

[0031] Figure 5 is a view illustrating the leads of the battery cell according to Embodiment 1 of the present invention.

[0032] Figure 6 is a front view illustrating a state in which the first lead and the second lead are arranged in opposite directions in the battery cell according to Embodiment 1 of the present invention.

[0033] Figure 7Is a front view of a battery cell according to Embodiment 2 of the present invention.

[0034] Figure 8 Is a front view illustrating a state in which a first lead and a second lead are arranged in opposite directions in the battery cell according to Embodiment 2 of the present invention. Detailed Description of the Embodiment

[0035] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement the present invention. However, the present invention can be implemented in several different forms and is not limited or defined by the following examples.

[0036] To clearly explain the present invention, parts irrelevant to the description or detailed descriptions of related known technologies that may unnecessarily obscure the gist of the present invention are omitted, and reference signs are added to components in each drawing in this specification. In this case, throughout the specification, the same or similar reference signs are assigned to the same or similar elements.

[0037] Furthermore, the terms or words used in this specification and claims should not be construed restrictively as ordinary meanings or dictionary-based meanings, but should be construed as meanings and concepts that conform to the scope of the present invention based on the principle that the inventor can appropriately define the terms to best describe and explain his invention.

[0038] Embodiment 1

[0039] Hereinafter, with reference to Figure 1 and Figure 6 Embodiment 1 of the present invention will be described in detail.

[0040] Figure 1 Is a front view of a battery cell according to Embodiment 1 of the present invention, Figure 2 Is an enlarged view illustrating a positive electrode terminal and a first lead of the battery cell according to Embodiment 1 of the present invention, Figure 3 Is an enlarged view illustrating a negative electrode terminal and a second lead of the battery cell according to Embodiment 1 of the present invention, Figure 4 Is a front view illustrating an electrode and an electrode terminal of the battery cell according to Embodiment 1 of the present invention, Figure 5 Is a view illustrating a lead of the battery cell according to Embodiment 1 of the present invention, and Figure 6 Is a front view illustrating a state in which a first lead and a second lead are arranged in opposite directions in the battery cell according to Embodiment 1 of the present invention.

[0041] Refer to Figures 1 to 6, the battery cell 1 according to Embodiment 1 of the present invention includes an electrode 10, an electrode terminal 20, and an electrode lead 30. The battery cell 1 according to Embodiment 1 of the present invention may be a pouch cell.

[0042] The electrode 10 may extend in a first direction A1. A second direction A2 is a direction perpendicular to the first direction A1. Since the electrode 10 extends in the first direction A1, the length of the electrode 10 in the first direction A1 may be greater than the length of the electrode 10 in the second direction A2.

[0043] The electrode terminals 20 may be provided at each of the two ends of the electrode 10 in the first direction A1. The electrode terminals 20 may include a positive terminal 21 and a negative terminal 22. The electrode terminals 20 are used to connect the electrode 10 to an external circuit. The electrode terminals 20 may be made of metal.

[0044] The positive terminal 21 may be provided at one end of the electrode 10. The positive terminal 21 may be connected to the positive electrode of the electrode 10. The positive terminal 21 may be arranged such that its length T1 in the second direction A2 is greater than its length T2 in the first direction A1.

[0045] The negative terminal 22 may be provided at the other end of the electrode 10. The negative terminal 22 may be connected to the negative electrode of the electrode 10. The negative terminal 22 may be arranged such that its length T4 in the second direction A2 is greater than its length T3 in the first direction A1.

[0046] Regarding the second direction A2, each of the lengths of the positive terminal 21 and the negative terminal 22 may be the same as the length of the electrode 10. Since in the second direction A2, each of the lengths of the positive terminal 21 and the negative terminal 22 is the same as the length of the electrode 10, a separate cutting process may not be required in the process of forming the positive terminal 21 and the negative terminal 22. Since there is no process of cutting the electrode terminals 20, the risk of the positive terminal 21 and the negative terminal 22 being torn can be reduced to achieve structural stability. By maximizing the lengths of the positive terminal 21 and the negative terminal 22 in the second direction A2, there is an advantage of dispersing the heat generation of the electrode terminals 20.

[0047] The electrode leads 30 may be coupled to the electrode terminals 20. The electrode leads 30 may be coupled to a plurality of electrode terminals 20. The electrode leads 30 may extend in a second direction A2 perpendicular to the first direction A1. The electrode leads 30 may include a first lead 31 and a second lead 32. In the second direction A2, one edge of the electrode lead 30 and one edge of the electrode terminal 20 may be arranged to correspond to each other. The electrode leads 30 may connect the electrode 10 and an external circuit. The electrode leads 30 may send current signals and voltage signals required to control the electrode 10 to an external circuit.

[0048] The first lead 31 can be disposed at one end of the electrode 10. In the first lead 31, the length L1 in the second direction A2 can be greater than the length L2 in the first direction A1.

[0049] The first lead 31 can include a first coupling portion 33 coupled to the positive electrode terminal 21. The first lead 31 can be welded to the positive electrode terminal 21 through the first coupling portion 33. As the area of the first coupling portion 33 increases, the coupling force with the positive electrode terminal 21 can increase. When a plurality of electrodes 10 are provided, a plurality of positive electrode terminals 21 can also be provided, and thus, the plurality of positive electrode terminals 21 can be connected to the first lead 31.

[0050] The second lead 32 can be disposed at the other end of the electrode 10. In the second lead 32, the length L3 in the second direction A2 can be greater than the length L4 in the first direction A1.

[0051] The second lead 32 can include a second coupling portion 34 coupled to the negative electrode terminal 22. The second lead 32 can be welded to the negative electrode terminal 22 through the second coupling portion 34. As the area of the second coupling portion 34 increases, the coupling force with the negative electrode terminal 22 can increase. When a plurality of electrodes 10 are provided, a plurality of negative electrode terminals 22 can also be provided, and thus, the plurality of negative electrode terminals 22 can be connected to the second lead 32.

[0052] The first coupling portion 33 and the second coupling portion 34 can have the same length as the positive electrode terminal 21 and the negative electrode terminal 22 in the second direction A2. Therefore, the first lead 31 and the second lead 32 can be arranged to be longer than the positive electrode terminal 21 and the negative electrode terminal 22 in the second direction A2.

[0053] The battery cell 1 according to Embodiment 1 of the present invention may further include a battery case 40. The battery case 40 can accommodate the electrode 10 and the electrode terminal 20. The first lead 31 and the second lead 32 can protrude from the battery case 40. The battery case 40 can protect the electrode 10, the electrode terminal 20, and the leads 30 from the external environment. The battery case 40 can be made of a pouch material.

[0054] The first lead 31 and the second lead 32 can protrude in the same direction in the second direction A2. The first lead 31 and the second lead 32 can have the same length protruding from the battery case 40. The first lead 31 can be coupled to the positive electrode terminal 21 by welding. The second lead 32 can be coupled to the negative electrode terminal 22 by welding.

[0055] Although the first lead 31 and the second lead 32 can be arranged to protrude in the same direction with respect to the second direction A2, it is not limited thereto, and the first lead 31 and the second lead 32 can also be as Figure 6The setting shown is configured to protrude in opposite directions.

[0056] In the battery cell 1 according to Embodiment 1 of the present invention, the first lead 31 and the second lead 32 may protrude in the second direction A2, and the lengths T1 and T3 of the positive electrode terminal 21 and the negative electrode terminal 22 in the second direction A2 may be the same as the length of the electrode 10. Since the first lead 31 and the second lead 32 protrude in the second direction A2, the welding area between the electrode terminal 20 and the electrode lead 30 can be maximized. Additionally, the bus bar connected to the electrode lead 30 can be designed to be disposed in the second direction A2 of the battery cell. Further, by maximizing the sizes of the electrode lead 30 and the electrode terminal 20, there is an effect of heat dissipation.

[0057] Since the bus bar connected to the electrode lead 30 is designed to face the upper side of the battery cell rather than the side surface of the battery cell, the bus bar can be freely designed by utilizing a wider space. Different from the conventional battery cell structure, since the electrode lead 30 protrudes in the second direction A2 of the battery cell 1, even when the battery cell 1 is applied to a module in a parallel structure, the electrode terminal 20 does not bend. Additionally, since the electrode lead 30 protrudes in the second direction A2 of the battery cell 1, the length of the entire battery module can be reduced.

[0058] In the related art, an end plate is required on the side surface of the battery module. However, in the battery cell 1 according to Embodiment 1 of the present invention, since the electrode lead 30 is designed to be disposed on the upper or lower part of the battery module rather than on the side surface, an end plate may not be required on the side surface of the battery module, and thus, by designing a battery module without an end plate, there can be an effect of cost reduction.

[0059] Embodiment 2

[0060] Hereinafter, reference will be made to Figure 7 and Figure 8 to describe in detail the battery cell 1 according to Embodiment 2 of the present invention.

[0061] Figure 7 is a front view of the battery cell according to Embodiment 2 of the present invention, and Figure 8 is a front view illustrating a state in which the first lead and the second lead are arranged in opposite directions in the battery cell according to Embodiment 2 of the present invention.

[0062] In the battery cell 1 according to Embodiment 2 of the present invention, the shape of the electrode terminal 20 is different from the shape of the electrode terminal 20 of the battery cell 1 according to Embodiment 1 of the present invention. Contents repeated with Embodiment 1 will be omitted as much as possible, and Embodiment 2 will be described focusing on the differences.

[0063] Refer toFigure 7 and Figure 8 In the second direction A2, the length T5 of the positive electrode terminal 21 is less than the length of the electrode 10. The length T6 of the negative electrode terminal 22 is also less than the length of the electrode 10. The length T5 of the positive electrode terminal 21 may be the same as the length T6 of the negative electrode terminal 22.

[0064] The first lead 31 and the second lead 32 may be arranged in the second direction A2. The first lead 31 and the second lead 32 may be arranged in the same direction along the second direction A2, or may be arranged to protrude in opposite directions.

[0065] The battery cell 1 according to Embodiment 2 of the present invention may be a pouch cell.

[0066] The battery cell 1 according to Embodiment 2 of the present invention may have the same effect as the battery cell 1 according to Embodiment 1. When compared with the battery cell 1 according to Embodiment 1, although the electrode terminal 20 is designed to protrude further in the first direction A1 and the length of the electrode terminal 20 in the second direction A2 is less than the length of the electrode 10, the first lead 31 and the second lead 32 extend in the second direction A2. Therefore, like in Embodiment 1, the bus bar can be freely designed, and different from the existing battery cells, the bending phenomenon of the electrode terminal 20 can be prevented, thereby reducing the length of the entire battery module.

[0067] Although the embodiments of the present invention have been described with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention as defined by the appended claims.

[0068] [Description of Symbols]

[0069] 1: Battery cell 10: Electrode

[0070] 20: Electrode terminal 21: Positive electrode terminal

[0071] 22: Negative electrode terminal 30: Electrode lead

[0072] 31: First lead 32: Second lead

[0073] 33: First connection part 34: Second connection part

[0074] 40: Battery case A1: First direction

[0075] A2: Second direction

Claims

1. A battery cell, the battery cell comprising: An electrode; Electrode connectors, the electrode connectors being provided at each of the two ends of the electrode in a first direction; And Electrode leads, the electrode leads being coupled to the electrode connectors to extend in a second direction perpendicular to the first direction.

2. The battery cell according to claim 1, wherein The electrode connectors comprise: A positive electrode connector, the positive electrode connector being provided at one end of the electrode; and A negative electrode connector, the negative electrode connector being provided at the other end of the electrode, Wherein, with respect to the second direction, each of the positive electrode connector and the negative electrode connector has the same length as the electrode.

3. The battery cell according to claim 2, wherein, The length of each of the positive electrode connector and the negative electrode connector in the second direction is greater than the length of each of the positive electrode connector and the negative electrode connector in the first direction.

4. The battery cell according to claim 1, wherein, The electrode leads comprise: A first lead, the first lead being provided at one end of the electrode; and A second lead, the second lead being provided at the other end of the electrode, Wherein, the first lead and the second lead extend in the same direction in the second direction.

5. The battery cell according to claim 4, wherein, The length of each of the first lead and the second lead in the second direction is greater than the length of each of the first lead and the second lead in the first direction.

6. The battery cell according to claim 4, wherein, The first lead includes a first coupling portion, the first coupling portion being coupled to the positive electrode connector, The second lead includes a second coupling portion, the second coupling portion being coupled to the negative electrode connector, and With respect to the second direction, the length of the first coupling portion and the length of the second coupling portion are the same as the length of each of the positive electrode connector and the negative electrode connector.

7. The battery cell according to claim 4, the battery cell further comprising a battery housing configured to accommodate the electrode and the electrode connectors, Among them, The first lead and the second lead protrude from the battery housing in the second direction.

8. The battery cell according to claim 7, wherein, The first lead and the second lead protrude from the battery housing in the same direction in the second direction.

9. The battery cell according to claim 7, wherein, The first lead and the second lead have the same length protruding from the battery housing.

10. The battery cell according to claim 1, wherein, With respect to the second direction, the edge on one side of the electrode lead and the edge on one side of the electrode connector are arranged to correspond to each other.

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