Electrode assembly for rechargeable battery

Abstract

An electrode assembly of a rechargeable battery includes a positive electrode plate, a negative electrode plate, and a separator between the electrode plates. Each of the electrode plates includes an electrode substrate, a first active material layer formed on a first surface of the electrode substrate, a second active material layer formed on a second surface of the electrode substrate, a first laminated tape attached to an end portion of the first active material layer, and a second laminated tape attached to an end portion of the second active material layer. The first and second laminated tapes each include a protruding portion protruding beyond an end portion of the electrode substrate.

Description

Technical Field

[0001] The present disclosure relates to an electrode assembly for a rechargeable battery, and more particularly, to an electrode assembly for a rechargeable battery having a laminated tape at an end of an electrode substrate. Background Art

[0002] Unlike disposable batteries, rechargeable batteries are batteries that are repeatedly charged and discharged. Small-capacity rechargeable batteries are used in portable small electronic devices (such as mobile phones, laptop computers, or video cameras). Large-capacity and high-density rechargeable batteries are used as, for example, a power source for driving an electric motor of a hybrid vehicle or an electric vehicle or an energy storage device of a hybrid vehicle or an electric vehicle.

[0003] A rechargeable battery includes an electrode assembly for charge current and discharge current, a case or pouch for accommodating the electrode assembly and an electrolyte, and an electrode terminal connected to the electrode assembly to lead current out from the electrode assembly to the outside of the case or pouch.

[0004] The electrode assembly may be a core type formed by winding an electrode plate and a separator. The winding process produces a core by winding a negative electrode substrate, a positive electrode substrate, and a separator as part of a process for manufacturing a cylindrical rechargeable battery.

[0005] If contact occurs between the negative electrode substrate and the positive electrode substrate in a rechargeable battery, there is a possibility of short circuit or fire. Therefore, for such contact between the positive electrode substrate and the negative electrode substrate, the substrate is cut, and then a laminated tape is attached to an end of the cut substrate. Attachment of the laminated tape is included in the winding process of the rechargeable battery.

[0006] In the laminated tape process, the laminated tape is attached to the front and end of the core, and then the laminated tape is cut to form a pattern. The laminated tape prevents a short circuit caused by deformation of the front portion of the positive electrode. Summary of the Invention

[0007] Embodiments of the present disclosure provide an electrode assembly for a rechargeable battery that prevents a short circuit caused by deformation of a positive electrode substrate and a negative electrode substrate.

[0008] Embodiments of the present disclosure provide an electrode assembly for a rechargeable battery that prevents cracks in a positive electrode substrate and a negative electrode substrate that may be caused by an adhesive layer of a laminated tape. Embodiments of the present disclosure provide an electrode assembly for a rechargeable battery that extends the life of a cutting unit (or cutting device) for cutting a laminated tape by minimizing an adhesive layer of the laminated tape.

[0009] An electrode assembly for a rechargeable battery may include a positive electrode plate, a negative electrode plate, and a separator located between the positive electrode plate and the negative electrode plate. The positive electrode plate, the negative electrode plate, and the separator are formed into a wound structure. Each of the positive electrode plate and the negative electrode plate may include: an electrode substrate; a first active material layer formed on a first surface of the electrode substrate; a second active material layer formed on a second surface of the electrode substrate; a first laminated tape attached to an end of the first active material layer, the first laminated tape including a protruding portion protruding beyond an end of the electrode substrate; and a second laminated tape attached to an end of the second active material layer, the second laminated tape including a protruding portion protruding beyond an end of the electrode substrate.

[0010] The protruding portions of the first laminated tape and the second laminated tape include first non-adhesive portions separated from each other outside a cross-section of the first active material layer and the second active material layer.

[0011] The first non-adhesive portions may be cut by a knife during the process of forming the two electrode plates.

[0012] The electrode substrate, the first active material layer, and the second active material layer may form a cross-section of the positive electrode plate and the negative electrode plate.

[0013] A first adhesive layer of the first laminated tape and a second adhesive layer of the second laminated tape may form a main adhesive portion above the first active material layer and below the second active material layer. The first adhesive layer and the second adhesive layer form an outer adhesive portion extending beyond the first active material layer and the second active material layer, and the first adhesive layer and the second adhesive layer are attached to each other in the outer adhesive portion.

[0014] The first laminated tape and the second laminated tape may form first non-adhesive portions separated from each other beyond the outer adhesive portion.

[0015] The first laminated tape and the second laminated tape may form second non-adhesive portions separated from each other above the first active material layer and below the second active material layer.

[0016] The electrode substrate extends farther than the first active material layer and the second active material layer.

[0017] The first active material layer may be formed on a first surface of the electrode substrate, the second active material layer may be formed on a second surface of the electrode substrate, a first cross-section of the first active material layer and a second cross-section of the second active material layer may be disposed at unaligned positions, the first laminated tape may be attached to the first surface of the electrode substrate through the first adhesive layer, and the second laminated tape may be attached to the second surface of the electrode substrate through the second adhesive layer.

[0018] The first laminated tape and the second laminated tape may further include non-adhesive portions separated from each other outside a cross-section of the electrode substrate.

[0019] The first pressure belt and the second pressure belt can form non - adhesive portions separated from each other on the first active material layer and the second active material layer therebetween.

[0020] According to an embodiment of the present disclosure, the first pressure belt and the second pressure belt can include protruding portions that protrude beyond the ends of the electrode substrate, so as to prevent short - circuits caused by deformation of the positive electrode substrate and the negative electrode substrate.

[0021] In an embodiment, the first pressure belt and the second pressure belt can further include non - adhesive portions separated from each other outside the cross - section of the first active material layer and the second active material layer, so as to prevent cracks in the positive electrode substrate and the negative electrode substrate caused by the adhesive layers of the first pressure belt and the second pressure belt.

[0022] According to an embodiment, due to the minimization of the adhesive layer in each of the first pressure belt and the second pressure belt, the life of the knife used for cutting the pressure belt can be extended. Brief Description of the Drawings

[0023] Figure 1 is a perspective view of an electrode assembly of a rechargeable battery according to a first embodiment of the present disclosure.

[0024] Figure 2 is before Figure 1 the electrode plate is cut.

[0025] Figure 3 is a cross - sectional view of a process of attaching the first pressure belt and the second pressure belt to the electrode plate and cutting the first pressure belt and the second pressure belt.

[0026] Figure 4 is during Figure 3 the first pressure belt and the second pressure belt are cut.

[0027] Figure 5 is a cross - sectional view showing the state where the first pressure belt and the second pressure belt attached to the electrode plate of the electrode assembly applied to a rechargeable battery according to a second embodiment of the present disclosure are cut.

[0028] Figure 6 is a cross - sectional view of a process of attaching the first pressure belt and the second pressure belt to the electrode plate of the electrode assembly applied to a rechargeable battery according to a third embodiment of the present disclosure and cutting the first pressure belt and the second pressure belt.

[0029] Figure 7 is during Figure 6 the first pressure belt and the second pressure belt are cut.

[0030] Figure 8 is a perspective view of an electrode assembly of a rechargeable battery according to a fourth embodiment of the present disclosure.

[0031] Figure 9 is Figure 8 a partial cross-sectional view of the electrode assembly.

[0032] Figure 10 is a partial cross-sectional view of the electrode assembly of a rechargeable battery according to a fifth embodiment of the present disclosure.

[0033] Figure 11 is a partial cross-sectional view of the electrode assembly of a rechargeable battery according to a sixth embodiment of the present disclosure.

[0034] Figure 12 is a partial cross-sectional view of the electrode assembly of a rechargeable battery according to a seventh embodiment of the present disclosure.

[0035] Figure 13 is a partial cross-sectional view of the electrode assembly of a rechargeable battery according to an eighth embodiment of the present disclosure.

[0036] Figure 14 is a partial cross-sectional view of the electrode assembly of a rechargeable battery according to a ninth embodiment of the present disclosure. Detailed Description of Embodiments

[0037] Hereinafter, embodiments of the present disclosure will be described more fully with reference to the accompanying drawings, so that those skilled in the art can easily implement the embodiments. The present disclosure can be modified in various different ways without departing from the scope of the present disclosure. To clearly describe the present disclosure, components or parts irrelevant to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

[0038] The electrode assembly has a Type A Figure 1 is a perspective view of the electrode assembly of a rechargeable battery according to a first embodiment of the present disclosure. Referring to Figure 1 , the electrode assembly 1 of the rechargeable battery according to the first embodiment can be configured to charge and discharge, and can be formed into a jelly-roll type by stacking and winding two separators S and electrode plates E of a negative electrode and a positive electrode.

[0039] Although not shown separately in the drawings, the electrode assembly can be embedded in a case together with an electrolyte, an opening of the case can be sealed with a cover plate, and electrode terminals can be led to the outside of the cover plate to form a rechargeable battery.

[0040] As an example, the electrode plate E can be formed as a positive electrode by coating a positive electrode active material on both surfaces of an electrode substrate 10 (see Figure 2 ) formed of aluminum (Al) foil, or can be formed as a negative electrode by coating a negative electrode active material on an electrode substrate 10 formed of copper (Cu) foil.

[0041] Figure 2 is Figure 1 A cross-sectional view of the electrode plate before being cut, and Figure 3 is a cross-sectional view of a process of attaching the first and second laminated tapes to the electrode plate and cutting the first and second laminated tapes.

[0042] Reference Figures 1 to 3 The electrode plate E may include a first active material layer 21 and a second active material layer 22, such that the active material is coated on both surfaces of the electrode substrate 10 formed of a thin metal plate. The electrode substrate 10 may include a first surface and a second surface, the first surface being arranged to face outward in the diameter direction when the electrode substrate 10 is in a wound state, and the second surface being arranged to face inward in the diameter direction when the electrode substrate 10 is in the wound state. The first active material layer 21 may be formed on the first surface, and the second active material layer 22 may be formed on the second surface.

[0043] In some embodiments, the electrode plate E may include a first active material layer 21 and a second active material layer 22, and an uncoated portion 11, where the electrode substrate 10 is exposed due to the absence of an active material coating. The uncoated portion 11 of the electrode plate E may be formed between the start and end of the electrode assembly in the winding direction, or between the start and end. However, in the first embodiment, the uncoated portion 11 of the electrode plate E may be formed at the center between the start and end.

[0044] The negative and positive electrode tabs T may be connected to the uncoated portion 11 of the electrode substrate 10. The negative and positive electrode tabs may be extended to at least one of the ends of the electrode assembly in the direction of the winding axis. In this embodiment, the negative and positive electrode tabs may be extended at both ends in the direction of the winding axis. The uncoated portion 11 and the tabs T may be insulated from the outside by a laminate tape 40.

[0045] The electrode plate E may include a first laminate tape 41 and a second laminate tape 42 attached to the start and end portions of the winding direction. For example, the first laminate tape 41 may be attached to the end portion of the first active material layer 21 via a first adhesive layer 411. The second laminate tape 42 may be attached to the end portion of the second active material layer 22 via a second adhesive layer 421.

[0046] Figure 4 Yes Figure 3 , which is a cross-sectional view showing a state in which the first laminated tape and the second laminated tape are cut. Figure 4, the first pressing belt 41 and the second pressing belt 42 can be attached to each other outside the cross-section of the first active material layer 21, the second active material layer 22, and the electrode substrate 10. The first pressing belt 41 and the second pressing belt 42 attached to each other can include protruding portions 43 (or 412, 422) protruding from the end of the electrode substrate 10. The protruding portions 43 (or 412, 422) of the first pressing belt 41 and the second pressing belt 42 can prevent short circuits caused by deformation of the electrode substrate 10.

[0047] In some embodiments, the protruding portions 43 (or 412, 422) of the first pressing belt 41 and the second pressing belt 42 can include a first non-bonding portion 44, and the first non-bonding portion 44 is separated from each other outside the cross-section of the first active material layer 21 and the second active material layer 22. The first non-bonding portions 44 of the first pressing belt 41 and the second pressing belt 42 can prevent short circuits caused by deformation of the electrode substrate 10 due to the first bonding layer 411 and the second bonding layer 421.

[0048] The first non-bonding portion 44 can be cut by a knife 50 to form two different electrode plates E. Two electrode plates E can be manufactured by a single cutting process, and the first non-bonding portion 44 can be disposed on one side of each electrode plate E.

[0049] In the first embodiment, the electrode substrate 10, the first active material layer 21, and the second active material layer 22 can form a cross-section at the same position. The first bonding layer 411 of the first pressing belt 41 and the second bonding layer 421 of the second pressing belt 42 can form a main bonding portion 451 on the first active material layer 21 and the second active material layer 22, and can also form an outer bonding portion 452 outside the cross-section of the first active material layer 21 and the second active material layer 22 (attached to each other by the main bonding portion 451).

[0050] The first non-bonding portion 44 formed by the first pressing belt 41 and the second pressing belt 42 can be formed to be separated from each other outside the outer bonding portion 452. Due to the first non-bonding portions 44 of the first pressing belt 41 and the second pressing belt 42, the first bonding layer 411 and the second bonding layer 421 can be minimized, so that the life of the knife 50 for cutting the first pressing belt 41 and the second pressing belt 42 is extended.

[0051] Hereinafter, various modification examples and embodiments of the present disclosure will be described. Descriptions of configurations identical to those of the first embodiment will be omitted, and descriptions of configurations different from those of the first embodiment will be provided.

[0052] Figure 5It is a cross-sectional view showing a state in which a first lamination tape and a second lamination tape attached to an electrode plate of an electrode assembly applied to a rechargeable battery according to a second embodiment of the present disclosure are cut. Refer to Figure 5 , in an electrode plate E2 of an electrode assembly of a rechargeable battery according to a second embodiment, a first non-adhesive portion 46 (or 612, 622) that separates above a first active material layer 21 and below a second active material layer 22 may be formed in a first lamination tape 61 and a second lamination tape 62.

[0053] If the rechargeable battery is charged and discharged, the second non-adhesive portions 46 (or 612, 622) of the first lamination tape 61 and the second lamination tape 62 may prevent cracks from occurring at the ends of the first lamination tape 61 and the second lamination tape 62. For example, the electrode plate E2 may become thick due to a first adhesive layer 411 and a second adhesive layer 421, such that internal stress is generated at the starting portion and the end portion of the electrode plate E2 when the electrode plate is wound. Therefore, cracks may occur. Specifically, the first adhesive layer 411 and the second adhesive layer 421 may be fixed to the electrode plate E2, such that there is interference with the flow of the first active material layer 21 and the second active material layer 22, and thus cracks may occur. However, the second non-adhesive portions 46 (or 612, 622) where the first adhesive layer 411 and the second adhesive layer 421 do not exist may reduce the internal stress at the ends of the first lamination tape 61 and the second lamination tape 62, and may enable the flow between the second non-adhesive portions 46 (or 612, 622) and the first active material layer 21 and the second active material layer 22. Therefore, the active material may not be dragged, and the occurrence of cracks may be prevented.

[0054] Figure 6 It is a cross-sectional view of a process of attaching a first lamination tape and a second lamination tape to an electrode plate of an electrode assembly applied to a rechargeable battery according to a third embodiment of the present disclosure and cutting the first lamination tape and the second lamination tape, and Figure 7 is a cross-sectional view of a state in which the first lamination tape and the second lamination tape are cut in Figure 6 .

[0055] Refer to Figure 6 and Figure 7 , in an electrode plate E3 of an electrode assembly of a rechargeable battery according to a third embodiment, an electrode substrate 12 may form a cross-section that extends farther than the cross-sections of a first active material layer 23 and a second active material layer 24. For example, the electrode substrate 12 may form an uncoated portion 13 at a certain distance from the ends of the first active material layer 23 and the second active material layer 24.

[0056] The first active material layer 23 may be formed on the first surface of the electrode substrate 12 (e.g., corresponding to the first surface of the uncoated portion 13), and the second active material layer 24 may be formed on the second surface of the electrode substrate 12 (e.g., corresponding to the second surface of the uncoated portion 13). The first cross-section of the first active material layer 23 and the second cross-section of the second active material layer 24 may be disposed at misaligned positions. For example, the uncoated portion 13 may be formed shorter on the second surface than on the first surface.

[0057] The first lamination tape 71 may be attached to the first surface of the electrode substrate 12 through the first adhesive layer 711, and the second lamination tape 72 may be attached to the second surface of the electrode substrate 12 through the second adhesive layer 721.

[0058] In some embodiments, the first lamination tape 71 and the second lamination tape 72 may include a third non-adhesive portion 74 (or 712, 722) that is separated from each other outside the cross-sections of the first active material layer 23 and the second active material layer 24. Due to the first adhesive layer 711 and the second adhesive layer 721, the third non-adhesive portion 74 (or 712, 722) of the first lamination tape 71 and the second lamination tape 72 may prevent crack defects from forming in the electrode substrate 12.

[0059] The third non-adhesive portion 74 (or 712, 722) may be cut by the knife 50 to form two different electrode plates E3. The two electrode plates E3 may be manufactured through a single cutting process, and the third non-adhesive portion 74 (or 712, 722) may be disposed at one side of each electrode plate E3.

[0060] The third non-adhesive portion 74 (or 712, 722) formed by the first lamination tape 71 and the second lamination tape 72 may be separated from each other outside the adhesive portion 752. The adhesive portion 752 may be different in the first adhesive layer 711 and the second adhesive layer 721 with respect to the cross-section positions of the first active material layer 23 and the second active material layer 24, but the difference may be indistinguishable in the present disclosure.

[0061] Due to the third non-adhesive portion 74 (or 712, 722) of the first lamination tape 71 and the second lamination tape 72, the first adhesive layer 711 and the second adhesive layer 721 may be minimized, so that the life of the knife 50 for cutting the first lamination tape 71 and the second lamination tape 72 is extended.

[0062] The first pressing belt 71 and the second pressing belt 72 can form mutually separated fourth non-bonding portions 76 (or 713, 723) on the first active material layer 23 and the second active material layer 24. The fourth non-bonding portions 76 (or 713, 723) of the first pressing belt 71 and the second pressing belt 72 can reduce the thickness of the starting portion and the end portion of the electrode plate, so that the curvature of the electrode plate is reduced when the electrode plate is wound. Therefore, the occurrence of cracks can be reduced. That is to say, if the rechargeable battery is charged and discharged, the fourth non-bonding portions 76 (or 713, 723) of the first pressing belt 71 and the second pressing belt 72 can prevent cracks from appearing at the end portions of the first pressing belt 71 and the second pressing belt 72. For example, the electrode plate E3 can become thick due to the first adhesive layer 711 and the second adhesive layer 721, so that internal stress is generated at the starting portion and the end portion of the electrode plate E3 when the electrode plate is wound. Therefore, cracks may appear. The first adhesive layer 711 and the second adhesive layer 721 can fix the electrode plate E3, thereby interfering with the flow of the first active material layer 23 and the second active material layer 24, so that cracks may appear. However, the fourth non-bonding portions 76 (or 713, 723) from which the first adhesive layer 711 and the second adhesive layer 721 are removed can reduce the internal stress at the end portions of the first pressing belt 71 and the second pressing belt 72, and can achieve the relative flow between the fourth non-bonding portions 76 (or 713, 723) and the first active material layer 23 and the second active material layer 24. Therefore, the active material can not be dragged, so as to prevent the appearance of cracks.

[0063] The electrode assembly having the B type Figure 8 is a perspective view of an electrode assembly of a rechargeable battery according to a fourth embodiment of the present disclosure, and Figure 9 is Figure 8 a partial cross-sectional view of the electrode assembly. Referring to Figure 8 and Figure 9 , the electrode assembly 5 of the rechargeable battery according to the fourth embodiment can be configured to be charged and discharged, and can be formed into a core type by stacking and winding two separators S and electrode plates of the negative electrode E41 and the positive electrode E42. For convenience, the separator S is omitted in Figure 9 .

[0064] Although not shown separately in the drawings, the electrode assembly can be embedded in a housing together with an electrolyte, the opening of the housing can be sealed with a cover plate, and the electrode terminals can be led out to the outside of the cover plate to form a rechargeable battery.

[0065] The positive electrode active material can be coated on two surfaces of an electrode substrate 420 formed of aluminum (Al) foil to form an electrode plate of the positive electrode E42. The negative electrode active material can be coated on an electrode substrate 410 formed of copper (Cu) foil to form an electrode plate of the negative electrode E41.

[0066] The electrode plate of the negative electrode E41 may include a first active material layer 121 and a second active material layer 122 in which the active material is coated on two surfaces of an electrode substrate 410 formed of a thin metal plate, and the electrode plate of the positive electrode E42 may include a first active material layer 221 and a second active material layer 222 in which the active material is coated on two surfaces of an electrode substrate 420 formed of a thin metal plate. In the negative electrode E41 and the positive electrode E42, the electrode substrates 410, 420 may include a first surface and a second surface. The first surface is arranged to face outward in the diameter direction when the electrode assembly is in a wound state, and the second surface is arranged to face inward in the diameter direction when the electrode assembly is in a wound state. The first active material layers 121, 221 may be formed on the first surface, and the second active material layers 122, 222 may be formed on the second surface.

[0067] In some embodiments, the electrode plate of the negative electrode E41 may include a first active material layer 121, a second active material layer 122, and an uncoated portion 131 where the electrode substrate 410 is exposed because the active material is not coated, and the electrode plate of the positive electrode E42 may include a first active material layer 221, a second active material layer 222, and an uncoated portion 132 where the electrode substrate 420 is exposed because the active material is not coated. The uncoated portion 131 of the negative electrode E41 and the uncoated portion 132 of the positive electrode E42 may be formed at the starting portion and the ending portion in the winding direction of the electrode assembly or at an intermediate position between the starting portion and the ending portion. However, in the fourth embodiment, the uncoated portion 131 of the negative electrode E41 and the uncoated portion 132 of the positive electrode E42 may be formed at the starting portion in the winding direction of the electrode assembly.

[0068] In the fourth embodiment, the electrode plate of the positive electrode E42 may include a first laminated tape 541 and a second laminated tape 542 attached to the starting portion in the winding direction. The first laminated tape 541 may be attached to the first surface of the uncoated portion 132 at the end of the first active material layer 221. The second laminated tape 542 may be attached to the second surface of the uncoated portion 132 at the end of the second active material layer 222.

[0069] The first laminated tape 541 and the second laminated tape 542 attached to the first surface and the second surface of the uncoated portion 132 may prevent short circuits caused by deformation of the electrode substrate 410 of the negative electrode E41 and the electrode substrate 420 of the positive electrode E42.

[0070] The first pressure belt 541 may form a first attachment portion (or outer layer portion) disposed on the first active material layer 221 at the winding center portion of the electrode assembly 5, and the second pressure belt 542 may form a second attachment portion (or inner layer portion) disposed on the second active material layer 222.

[0071] The end of the first attachment portion of the first pressure belt 541 on the first active material layer 221 and the end of the second attachment portion of the second pressure belt 542 on the second active material layer 222 may be spaced apart from each other in the winding direction. Specifically, the first attachment portion may be longer than the second attachment portion by a first length L1. The first length L1 may minimize the thickness difference in the winding diameter direction caused by the first pressure belt 541 and the second pressure belt 542, such that after winding, the first length L1 prevents cracks from occurring in the first active material layer 221 and the second active material layer 222 of the electrode assembly 5.

[0072] The first pressure belt 541 and the second pressure belt 542 may be attached to the first surface and the second surface of the uncoated portion 132, respectively, and may include a first extended attachment portion 543 that further extends from the end of the uncoated portion 132 and is attached to each other. The first extended attachment portion 543 may further prevent a short circuit caused by deformation of the electrode substrate 410 of the negative electrode E41 and the electrode substrate 420 of the positive electrode E42. The first extended attachment portion 543 may not correspond to the end of the first active material layer 121 of the negative electrode E41 to prevent cracks from occurring in the first active material layer 121 that may be caused by the first extended attachment portion 543.

[0073] In some embodiments, the first extended attachment portion 543 may be disposed at opposite sides in the diameter direction of the electrode assembly 5 to correspond to the first length L1. Therefore, the first extended attachment portion 543 may further prevent the occurrence of cracks caused by the thickness difference.

[0074] Figure 10 is a partial cross-sectional view of an electrode assembly of a rechargeable battery according to a fifth embodiment of the present disclosure. Referring to Figure 10 , in the electrode assembly 6 of the rechargeable battery according to the fifth embodiment, the electrode plate of the negative electrode E51 may include a first pressure belt 641 and a second pressure belt 642 attached to the starting portion in the winding direction. The first pressure belt 641 may be attached to the first surface of the uncoated portion 131 at the end of the first active material layer 121. The second pressure belt 642 may be attached to the second surface of the uncoated portion 131 at the end of the second active material layer 122.

[0075] The first lamination tape 641 attached to the first surface of the uncoated portion 131 and the second lamination tape 642 attached to the second surface of the uncoated portion 131 can prevent a short circuit caused by deformation of the electrode substrate 510 of the negative electrode E51 and the electrode substrate 520 of the positive electrode E52.

[0076] The first lamination tape 641 can form a first attachment portion (or outer layer portion) provided on the first active material layer 121 at the winding center portion of the electrode assembly 6, and the second lamination tape 642 can form a second attachment portion (or inner layer portion) provided on the second active material layer 122.

[0077] The end of the first attachment portion of the first lamination tape 641 on the first active material layer 121 and the end of the second attachment portion of the second lamination tape 642 on the second active material layer 122 can be spaced apart from each other in the winding direction. The first attachment portion can be shorter than the second attachment portion by a second length L2.

[0078] The second length L2 can minimize the thickness difference in the winding diameter direction caused by the first lamination tape 641 and the second lamination tape 642, so that after winding, the second length L2 prevents cracks from appearing in the first active material layer 121 and the second active material layer 122 of the electrode assembly 6.

[0079] The first lamination tape 641 and the second lamination tape 642 can be attached to the first surface and the second surface of the uncoated portion 131, respectively. The first lamination tape 641 and the second lamination tape 642 can include second extended attachment portions 643 that further extend from the ends of the uncoated portion 131 and are attached to each other. The second extended attachment portions 643 can further prevent a short circuit caused by deformation of the electrode substrate 510 of the negative electrode E51 and the electrode substrate 520 of the positive electrode E52.

[0080] In some embodiments, the second extended attachment portions 643 can be provided at opposite sides in the diameter direction of the electrode assembly 6 to correspond to the second length L2. Therefore, the second extended attachment portions 643 can further prevent the occurrence of cracks caused by the thickness difference.

[0081] Figure 11 is a partial cross-sectional view of an electrode assembly of a rechargeable battery according to a sixth embodiment of the present disclosure. Refer to Figure 11, in the electrode assembly 7 of the rechargeable battery according to the sixth embodiment, the electrode plate of the positive electrode E42 may include a first laminated tape 541 and a second laminated tape 542 attached to the starting portion in the winding direction. The first laminated tape 541 may be attached to the first surface of the uncoated portion 132 at the end of the first active material layer 221. The second laminated tape 542 may be attached to the second surface of the uncoated portion 132 at the end of the second active material layer 222. The first laminated tape 541 attached to the first surface of the uncoated portion 132 and the second laminated tape 542 attached to the second surface of the uncoated portion 132 may prevent a short circuit caused by deformation of the electrode substrate 510 of the negative electrode E51 and the electrode substrate 420 of the positive electrode E42.

[0082] The first laminated tape 541 may form a first attachment portion (or outer layer portion) provided on the first active material layer 221 at the winding center portion of the electrode assembly 7, and the second laminated tape 542 may form a second attachment portion (or inner layer portion) provided on the second active material layer 222.

[0083] The end of the first attachment portion of the first laminated tape 541 on the first active material layer 221 and the end of the second attachment portion of the second laminated tape 542 on the second active material layer 222 may be spaced apart from each other in the winding direction. The first attachment portion may be longer than the second attachment portion by a first length L1. The first length L1 may minimize the thickness difference in the winding diameter direction caused by the first laminated tape 541 and the second laminated tape 542, so that after winding, the first length L1 prevents cracks from appearing in the first active material layer 221 and the second active material layer 222 of the electrode assembly 7.

[0084] The first laminated tape 541 and the second laminated tape 542 may be respectively attached to the first surface and the second surface of the uncoated portion 132. The first laminated tape 541 and the second laminated tape 542 may include a first extended attachment portion 543 extending from the end of the uncoated portion 132 and attached to each other. The first extended attachment portion 543 may further prevent a short circuit caused by deformation of the electrode substrate 510 of the negative electrode E51 and the electrode substrate 420 of the positive electrode E42. The first extended attachment portion 543 may not correspond to the end of the first active material layer 121 of the negative electrode E51 to prevent cracks from appearing in the first active material layer 121 that may be caused by the first extended attachment portion 543.

[0085] In some embodiments, the first extended attachment portion 543 may be provided at opposite sides in the diameter direction of the electrode assembly 7 to correspond to the first length L1. Therefore, the first extended attachment portion 543 may further prevent the appearance of cracks caused by the thickness difference.

[0086] The electrode plate of the negative electrode E51 may include a first laminated tape 641 and a second laminated tape 642 attached to the starting portion in the winding direction. The first laminated tape 641 may be attached to the first surface of the uncoated portion 131 at the end of the first active material layer 121. The second laminated tape 642 may be attached to the second surface of the uncoated portion 131 at the end of the second active material layer 122. The first laminated tape 641 attached to the first surface of the uncoated portion 131 and the second laminated tape 642 attached to the second surface of the uncoated portion 131 may prevent a short circuit caused by deformation of the electrode substrate 510 of the negative electrode E51 and the electrode substrate 420 of the positive electrode E42.

[0087] The first laminated tape 641 may form a first attachment portion (or outer layer portion) provided on the first active material layer 121 at the winding center portion of the electrode assembly 7. The second laminated tape 642 may form a second attachment portion (or inner layer portion) provided on the second active material layer 122.

[0088] The end of the first attachment portion of the first laminated tape 641 on the first active material layer 121 and the end of the second attachment portion of the second laminated tape 642 on the second active material layer 122 may be spaced apart from each other in the winding direction. The first attachment portion may be shorter than the second attachment portion by a second length L2. The second length L2 may minimize the thickness difference in the winding diameter direction caused by the first laminated tape 641 and the second laminated tape 642, such that after winding, the second length L2 prevents cracks from appearing in the first active material layer 121 and the second active material layer 122 of the electrode assembly 7.

[0089] The first laminated tape 641 and the second laminated tape 642 may be respectively attached to the first surface and the second surface of the uncoated portion 131. The first laminated tape 641 and the second laminated tape 642 may include a second extended attachment portion 643 that further extends from the end of the uncoated portion 131 and is attached to each other. The second extended attachment portion 643 may further prevent a short circuit caused by deformation of the electrode substrate 510 of the negative electrode E51 and the electrode substrate 420 of the positive electrode E42. The second extended attachment portion 643 may be provided at opposite sides in the diameter direction of the electrode assembly 7 to correspond to the second length L2. Therefore, the second extended attachment portion 643 may further prevent the appearance of cracks caused by the thickness difference.

[0090] Figure 12 is a partial cross-sectional view of an electrode assembly of a rechargeable battery according to a seventh embodiment of the present disclosure. Referring to Figure 12 In the electrode assembly 8 of the rechargeable battery according to the seventh embodiment, the electrode plate of the positive electrode E44 may include a first laminated tape 551 and a second laminated tape 552 attached to the starting portion in the winding direction.

[0091] The first pressure belt 551 can be attached to the first active material layer 221 and can extend from an end portion of the first active material layer 221. The second pressure belt 552 can be attached to the second active material layer 222 and further extend from an end portion of the second active material layer 222. The extending portions of the first pressure belt 551 and the second pressure belt 552 can include a first extending attachment portion 843 attached to each other. The first extending attachment portion 843 of the first pressure belt 551 attached to the first active material layer 221 and the second pressure belt 552 attached to the second active material layer 222 can prevent a short circuit caused by deformation of the electrode substrate 430 of the negative electrode E43 and the electrode substrate 440 of the positive electrode E44.

[0092] The first pressure belt 551 can form a first attachment portion (or outer layer portion) provided on the first active material layer 221 at a winding center portion of the electrode assembly 8. The second pressure belt 552 can form a second attachment portion (or inner layer portion) provided on the second active material layer 222.

[0093] The end portion of the first attachment portion of the first pressure belt 551 on the first active material layer 221 and the end portion of the second attachment portion of the second pressure belt 552 on the second active material layer 222 can be spaced apart from each other in the winding direction. The first attachment portion can be longer than the second attachment portion by an eleventh length L11. The eleventh length L11 can minimize a thickness difference in the winding diameter direction caused by the first pressure belt 551 and the second pressure belt 552, such that after winding, the eleventh length L11 prevents cracks from occurring in the first active material layer 221 and the second active material layer 222 of the electrode assembly 8.

[0094] The first extending attachment portion 843 can be provided at opposite sides in the diameter direction of the electrode assembly 8 to partially correspond to the eleventh length L11. Accordingly, the first extending attachment portion 843 can further prevent the occurrence of cracks caused by the thickness difference.

[0095] Figure 13 is a partial cross-sectional view of an electrode assembly of a rechargeable battery according to an eighth embodiment of the present disclosure. Referring to Figure 13 , in the electrode assembly 9 of the rechargeable battery according to the eighth embodiment, the electrode plate of the negative electrode E53 can include a first pressure belt 651 and a second pressure belt 652 attached to a starting portion in the winding direction.

[0096] The first pressure belt 651 can be attached to the first active material layer 121 and can extend from the end of the first active material layer 121. The second pressure belt 652 can be attached to the second active material layer 122 and can extend from the end of the second active material layer 122. The extending portions of the first pressure belt 651 and the second pressure belt 652 can include second extending attachment portions 943 attached to each other. The second extending attachment portions 943 of the first pressure belt 651 attached to the first active material layer 121 and the second pressure belt 652 attached to the second active material layer 122 can prevent short circuits caused by deformation of the electrode substrate 430 of the negative electrode E53 and the electrode substrate 440 of the positive electrode E54.

[0097] The first pressure belt 651 can form a first attachment portion (or outer layer portion) provided on the first active material layer 121 at the winding center portion of the electrode assembly 9. The second pressure belt 652 can form a second attachment portion (or inner layer portion) provided on the second active material layer 122. The end of the first attachment portion of the first pressure belt 651 on the first active material layer 121 and the end of the second attachment portion of the second pressure belt 652 on the second active material layer 122 can be spaced apart from each other in the winding direction. The first attachment portion can be shorter than the second attachment portion by the twelfth length L12. The twelfth length L12 can minimize the thickness difference in the winding diameter direction caused by the first pressure belt 651 and the second pressure belt 652, so that after winding, the twelfth length L12 prevents cracks from appearing in the first active material layer 121 and the second active material layer 122 of the electrode assembly 9.

[0098] In some embodiments, the second extending attachment portions 943 can be provided at opposite sides in the diameter direction of the electrode assembly 9 to partially correspond to the twelfth length L12. Therefore, the second extending attachment portions 943 can further prevent the appearance of cracks caused by the thickness difference.

[0099] Figure 14 is a partial cross-sectional view of an electrode assembly of a rechargeable battery according to a ninth embodiment of the present disclosure. Referring to Figure 14 , in the electrode assembly 4 of the rechargeable battery of the ninth embodiment, the electrode plate of the positive electrode E44 can include a first pressure belt 551 and a second pressure belt 552 attached to the starting portion in the winding direction.

[0100] The first pressure belt 551 can be attached to the first active material layer 221 and can extend from the end of the first active material layer 221. The second pressure belt 552 can be attached to the second active material layer 222 and can extend from the end of the second active material layer 222. The extending portions of the first pressure belt 551 and the second pressure belt 552 can include first extending attachment portions 843 attached to each other.

[0101] The first lamination tape 551 attached to the first active material layer 221 and the first extended attachment portion 843 of the second lamination tape 552 attached to the second active material layer 222 can prevent a short circuit caused by deformation of the electrode substrate 430 of the negative electrode E53 and the electrode substrate 440 of the positive electrode E44.

[0102] The first lamination tape 551 can form a first attachment portion (or outer layer portion) provided on the first active material layer 221 at the winding center portion of the electrode assembly 4. The second lamination tape 552 can form a second attachment portion (or inner layer portion) provided on the second active material layer 222.

[0103] The end of the first attachment portion of the first lamination tape 551 on the first active material layer 221 and the end of the second attachment portion of the second lamination tape 552 on the second active material layer 222 can be spaced apart from each other in the winding direction. The first attachment portion can be longer than the second attachment portion by an eleventh length L11. The eleventh length L11 can minimize the thickness difference in the winding diameter direction caused by the first lamination tape 551 and the second lamination tape 552, so that after winding, the eleventh length L11 prevents cracks from appearing in the first active material layer 221 and the second active material layer 222 of the electrode assembly 4.

[0104] The first extended attachment portion 843 can be provided on opposite sides in the diameter direction of the electrode assembly 4 to partially correspond to the eleventh length L11. Therefore, the first extended attachment portion 843 can further prevent the appearance of cracks due to the thickness difference.

[0105] In the electrode assembly 4 of the rechargeable battery of the ninth embodiment, the electrode plate of the negative electrode E53 can include a first lamination tape 651 and a second lamination tape 652 attached to the starting portion in the winding direction. The first lamination tape 651 can be attached to the first active material layer 121 and can extend from the end of the first active material layer 121. The second lamination tape 652 can be attached to the second active material layer 122 and can extend from the end of the second active material layer 122. The extended portions of the first lamination tape 651 and the second lamination tape 652 can include a second extended attachment portion 943 attached to each other. The second extended attachment portion 943 of the first lamination tape 651 attached to the first active material layer 121 and the second lamination tape 652 attached to the second active material layer 122 can prevent a short circuit caused by deformation of the electrode substrate 430 of the negative electrode E53 and the electrode substrate 440 of the positive electrode E44.

[0106] The first pressure belt 651 can form a first attachment portion (or outer layer portion) disposed on the first active material layer 121 at the winding center portion of the electrode assembly 4. The second pressure belt 652 can form a second attachment portion (or inner layer portion) disposed on the second active material layer 122.

[0107] The end of the first attachment portion of the first pressure belt 651 on the first active material layer 121 and the end of the second attachment portion of the second pressure belt 652 on the second active material layer 122 can be spaced apart from each other in the winding direction. The first attachment portion can be shorter than the second attachment portion by a twelfth length L12. The twelfth length L12 can minimize the thickness difference in the winding diameter direction caused by the first pressure belt 651 and the second pressure belt 652, such that after winding, the twelfth length L12 prevents cracks from occurring in the first active material layer 121 and the second active material layer 122 of the electrode assembly 4.

[0108] In some embodiments, the second extended attachment portion 943 can be disposed at opposite sides in the diameter direction of the electrode assembly 4 to partially correspond to the twelfth length L12. Accordingly, the second extended attachment portion 943 can further prevent the occurrence of cracks due to the thickness difference.

[0109] Although the present disclosure has been described in connection with what are presently considered to be practical embodiments, it is to be understood that the disclosure is not limited to the disclosed embodiments. On the contrary, the disclosure is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.

[0110] <Description of reference numerals> 10, 12: Electrode substrate 11: Uncoated portion 21, 23: First active material layer 22, 24: Second active material layer 40: Pressure belt 41: First pressure belt 42: Second pressure belt 43, 412, 422: Protruding portion 44: First non-adhesive portion 46, 612, 622: Second non-adhesive portion 50: Knife 61, 71: First pressure belt 62, 72: Second pressure belt 411: First adhesive layer 421: Second adhesive layer 451: Main adhesive portion 452: Outer adhesive portion 711: First adhesive layer 721: Second adhesive layer 74, 712, 722: Third non - adhesive part 752: Adhesive part 76, 713, 723: Fourth non - adhesive part E, E2, E3: Electrode plates S: Diaphragm T: Terminal tab.

Claims

1. An electrode assembly for a rechargeable battery, the electrode assembly comprising: a positive electrode plate; a negative electrode plate; and a separator located between the positive electrode plate and the negative electrode plate, wherein the positive electrode plate, the negative electrode plate, and the separator are formed into a wound structure, and wherein each of the positive electrode plate and the negative electrode plate includes: an electrode substrate; a first active material layer formed on a first surface of the electrode substrate; a second active material layer formed on a second surface of the electrode substrate; a first lamination tape attached to an end of the first active material layer, the first lamination tape including a protruding portion protruding beyond an end of the electrode substrate; and a second lamination tape attached to an end of the second active material layer, the second lamination tape including a protruding portion protruding beyond the end of the electrode substrate.

2. The electrode assembly according to claim 1, wherein, The protruding portion of the first lamination tape and the protruding portion of the second lamination tape include a first non-bonding portion separated from each other outside a cross-section of the first active material layer and the second active material layer.

3. The electrode assembly according to claim 2, wherein, The first non-bonding portion is cut by a knife during a process of forming two electrode plates.

4. The electrode assembly according to claim 1, wherein, The electrode substrate, the first active material layer, and the second active material layer form a cross-section of the positive electrode plate and the negative electrode plate.

5. The electrode assembly according to claim 3, wherein, A first bonding layer of the first lamination tape and a second bonding layer of the second lamination tape form a main bonding portion above the first active material layer and below the second active material layer, the first bonding layer and the second bonding layer form an outer bonding portion extending beyond the first active material layer and the second active material layer, and the first bonding layer and the second bonding layer are attached to each other in the outer bonding portion.

6. The electrode assembly according to claim 5, wherein, The first lamination tape and the second lamination tape form the first non-bonding portion separated from each other extending beyond the outer bonding portion.

7. The electrode assembly according to claim 3, wherein, The first lamination tape and the second lamination tape form a second non-bonding portion separated from each other above the first active material layer and below the second active material layer.

8. The electrode assembly according to claim 1, wherein, The electrode substrate extends farther than the first active material layer and the second active material layer.

9. The electrode assembly according to claim 8, wherein, A first cross-section of the first active material layer and a second cross-section of the second active material layer are disposed at misaligned positions, and wherein the first lamination tape is attached to the first surface of the electrode substrate through the first bonding layer, and the second lamination tape is attached to the second surface of the electrode substrate through the second bonding layer.

10. The electrode assembly according to claim 9, wherein, The first lamination tape and the second lamination tape further include a non-bonding portion separated from each other outside a cross-section of the electrode substrate.

11. The electrode assembly according to claim 8, wherein, The first lamination tape and the second lamination tape form a non-bonding portion separated from each other on the first active material layer and the second active material layer between the first lamination tape and the second lamination tape.

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