Secondary battery

Abstract

The secondary battery includes: an electrode assembly including a positive electrode plate, a negative electrode plate, and a separator; a lead portion electrically connected to the electrode assembly; a case accommodating the electrode assembly; and a reinforcing member inside the case, the reinforcing member surrounding a connection portion of the electrode assembly between the electrode assembly and the lead portion, the lead portion, and an edge of the electrode assembly.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2024-0156690, filed on November 7, 2024, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure relates to secondary batteries. Background Technology

[0004] Unlike primary batteries, which cannot be recharged, secondary batteries are rechargeable and dischargeable. Low-capacity secondary batteries can be used in various portable small electronic devices such as smartphones, feature phones, laptops, digital cameras, or camcorders, while high-capacity secondary batteries are widely used as power sources for motor drives in vehicles such as hybrid or electric vehicles. A secondary battery includes: an electrode assembly containing positive and negative electrodes; a housing of the electrode assembly; and electrode terminals connected to the electrode assembly.

[0005] The information disclosed in this background section is only intended to enhance the understanding of the background of the present invention, and therefore may contain information that does not constitute prior art. Summary of the Invention

[0006] The embodiment includes a secondary battery, comprising: an electrode assembly including a positive electrode plate, a negative electrode plate, and a separator; a lead portion electrically connected to the electrode assembly; a housing housing the electrode assembly; and a reinforcing member inside the housing surrounding the connection portion of the electrode assembly between the electrode assembly and the lead portion, the lead portion, and the edge of the electrode assembly.

[0007] The positive electrode plate, negative electrode plate, and diaphragm can be stacked or wound together.

[0008] The reinforcing member may include a strip or membrane attached to the outside of the electrode assembly.

[0009] The reinforcing components include adhesives and synthetic resins, the synthetic resins being selected from polyethylene terephthalate, polypropylene, and polyimide.

[0010] The reinforcing member may include: a first reinforcing member that wraps around the edge of the electrode assembly, the connecting portion of the electrode assembly, and the lead portion of the electrode assembly on a first side in the length direction of the electrode assembly; a second reinforcing member that wraps around the edge of the electrode assembly on a second side in the length direction of the electrode assembly; a third reinforcing member that wraps around the edge of the electrode assembly on one side in the width direction of the electrode assembly; and a fourth reinforcing member that wraps around the edge of the electrode assembly on the other side in the width direction of the electrode assembly.

[0011] The first reinforcing member may include: a first base that contacts the lower side of the electrode assembly; and a first cover that contacts the upper side of the electrode assembly and the first base, the first cover and the first base together wrapping around the upper edge of the electrode assembly.

[0012] The first reinforcing member may further include a fixing layer on the underside of the first base, the fixing layer having an adhesive component and being fixed to the housing.

[0013] One side of the first cover can be fixed to the upper side of the electrode assembly, and the first cover can be pressed by a work roller to be attached to the first base.

[0014] The first reinforcing member may further include an insulating portion containing insulating material, the insulating portion extending between the lead portion and the housing and being fixed to the housing by an adhesive component.

[0015] The first reinforcing member may include: a first reinforcing sub-member covering the positive electrode terminal of the electrode assembly; and a second reinforcing sub-member covering the negative electrode terminal of the electrode assembly, wherein the first reinforcing sub-member and the second reinforcing sub-member are spaced apart from each other.

[0016] The embodiment includes a secondary battery, comprising: an electrode assembly including a positive electrode plate, a negative electrode plate and a separator; a lead portion electrically connected to the electrode assembly; a housing housing the electrode assembly; and a reinforcing member inside the housing, the reinforcing member surrounding the connection portion between the electrode assembly and the lead portion, the lead portion, the edge of the electrode assembly and at least one of the upper and lower sides of the electrode assembly.

[0017] The reinforcing member may include: a first reinforcing member surrounding the edge of the electrode assembly, the connecting portion of the electrode assembly, and the lead portion of the electrode assembly, on a first side in the length direction of the electrode assembly; a second reinforcing member surrounding the edge of the electrode assembly on a second side in the length direction of the electrode assembly; a third reinforcing member surrounding the edge of the electrode assembly on one side in the width direction of the electrode assembly; a fourth reinforcing member surrounding the edge of the electrode assembly on the other side in the width direction of the electrode assembly; and a fifth reinforcing member surrounding at least one of the upper and lower sides of the electrode assembly.

[0018] The first reinforcing member may include a single reinforcing member that wraps around the positive electrode terminal and the negative electrode terminal of the electrode assembly.

[0019] The first reinforcing member may include: a first reinforcing sub-member surrounding the positive electrode terminal of the electrode assembly; and a second reinforcing sub-member surrounding the negative electrode terminal of the electrode assembly, wherein the first reinforcing sub-member and the second reinforcing sub-member are spaced apart from each other.

[0020] The first reinforcing member may include: a first base that contacts the lower side of the electrode assembly; and a first cover that contacts the upper side of the electrode assembly and the first base, the first cover and the first base together wrapping around the upper edge of the electrode assembly.

[0021] The first reinforcing member may further include a fixing layer on the underside of the first base, the fixing layer having an adhesive component and being fixed to the housing.

[0022] The first reinforcing member may further include an insulating portion containing insulating material, the insulating portion extending between the lead portion and the housing and being fixed to the housing by an adhesive component.

[0023] The fifth reinforcing member can be wrapped around the lower side of the electrode assembly.

[0024] The fifth reinforcing member may overlap with at least one of the first to fourth reinforcing members.

[0025] The reinforcing component may include an adhesive and a synthetic resin, the synthetic resin being selected from polyethylene terephthalate, polypropylene, and polyimide.

[0026] However, the technical problems to be solved in the embodiments of this disclosure are not limited to those mentioned above, and those skilled in the art to which this disclosure pertains will clearly understand other technical problems not mentioned herein through the following description.

[0027] However, the effects achievable by the present invention are not limited to those described above, and those skilled in the art can clearly understand from the above description of the present invention other technical effects not mentioned. Attached Figure Description

[0028] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the detailed description of the present disclosure, serve to further understand the technical concept of the present disclosure; therefore, the present disclosure should not be construed as limited to the contents described in these drawings.

[0029] Features will become apparent to those skilled in the art from the detailed description of exemplary embodiments with reference to the accompanying drawings, wherein:

[0030] Figure 1 This is a perspective view showing a secondary battery according to an embodiment of the present disclosure.

[0031] Figure 2 This is a perspective view showing the electrode assembly separated from the housing according to an embodiment of the present disclosure;

[0032] Figure 3 This is a front cross-sectional view of a secondary battery according to an embodiment of the present disclosure.

[0033] Figure 4 This is a front sectional view showing the state in which the reinforcing member is fixed to the housing according to an embodiment of the present disclosure;

[0034] Figure 5 This is a cross-sectional view showing the upper side of the reinforcing member in a secondary battery according to an embodiment of the present disclosure;

[0035] Figure 6 This is a cross-sectional view showing the lower side of the reinforcing member in a secondary battery according to an embodiment of the present disclosure;

[0036] Figure 7 This is a front view showing the state in which the first cover is mounted on the upper side and the first base is mounted on the lower side in an electrode assembly according to an embodiment of the present disclosure;

[0037] Figure 8 This is a front view showing the state in which the work roller, according to an embodiment of the present disclosure, presses down the first cover as it moves;

[0038] Figure 9 This is a plan view showing the reinforcing member and the work roller according to an embodiment of the present disclosure;

[0039] Figure 10 This is a cross-sectional view showing the upper side of a reinforcing member in a secondary battery according to another embodiment of the present disclosure;

[0040] Figure 11 This is a plan view showing a reinforcing member and a work roller according to another embodiment of the present disclosure;

[0041] Figure 12 This is a cross-sectional view showing the upper side of a reinforcing member in a secondary battery according to another embodiment of the present disclosure;

[0042] Figure 13 This is a cross-sectional view showing the lower side of a reinforcing member in a secondary battery according to another embodiment of the present disclosure;

[0043] Figure 14 This is a cross-sectional view showing the upper side of a reinforcing member in a secondary battery according to another embodiment of the present disclosure;

[0044] Figure 15 This is a cross-sectional view showing the lower side of a reinforcing member in a secondary battery according to another embodiment of the present disclosure;

[0045] Figure 16A and Figure 16B This is a perspective view showing a battery pack including an exemplary secondary battery according to the present disclosure;

[0046] Figure 17A and Figure 17BThese are perspective and side views of a vehicle including an exemplary battery pack according to this disclosure. Detailed Implementation

[0047] Exemplary embodiments will now be described more fully below with reference to the accompanying drawings; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey exemplary embodiments to those skilled in the art.

[0048] It should also be understood that when a layer or component is referred to as being "on" another layer or substrate, it can be directly on the other layer or substrate, or there may be intermediate layers. Furthermore, it should be understood that when a layer is referred to as being "below" another layer, it can be directly below the other layer, and there may be one or more intermediary layers. Additionally, it should be understood that when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or there may be one or more intermediary layers.

[0049] The present disclosure will now be described in detail. Before giving the following detailed description of the present disclosure, it should be noted that the terms and words used in the specification and claims should not be construed as limited to their ordinary meaning or dictionary definitions, but should be interpreted in a meaning and concept consistent with the technical concept of the present disclosure, based on the inventor's ability to appropriately define the concept of the terms in the best possible way to describe the present disclosure. Therefore, the embodiments described in this specification and the configurations described in the drawings are only the most preferred embodiments of the present disclosure and do not represent all the technical ideas of the present disclosure. It should be understood that various equivalents and variations may exist in place of them at the time of filing this application. Furthermore, when the term "comprising" and variations thereof are used in this specification as used herein, it specifies the presence of the stated features, numbers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, numbers, steps, operations, elements, components, and / or groups thereof. Additionally, in describing embodiments of the present disclosure, "may" and variations thereof may include "one or more embodiments of the present disclosure".

[0050] Furthermore, for a better understanding of the invention, the accompanying drawings are not drawn to scale, and the dimensions of some components may be enlarged. Additionally, in different embodiments, the same reference numerals may be assigned to the same components.

[0051] When comparing two objects, it means they are substantially the same. Therefore, the phrase "substantially the same" can include, for example, cases where the deviation is within 5%, which are considered low levels in the relevant art. Additionally, when any parameter is described as uniform in a given region, it can mean that the parameter is uniform from an average perspective.

[0052] It should be understood that although the terms “first,” “second,” “third,” etc., may be used herein to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the spirit and scope of this disclosure, unless otherwise defined, the first element, first component, first area, first layer, or first portion described below may be referred to as a second element, second component, second area, second layer, or second portion.

[0053] Throughout the manual, each component may be singular or plural unless the context clearly indicates otherwise.

[0054] The arrangement of any component "on the upper (or lower)" or "below (or above)" of a component means that any component is placed in contact with the upper (or lower) surface of the component. Additionally, it can mean that other components can be positioned between the component and any components disposed on (or below) it.

[0055] Furthermore, it should be understood that when an element is referred to as being “connected to,” “linked to,” or “attached to” another element, these elements may be directly connected or linked to each other, with another intermediary element present, or the corresponding elements may be connected, linked, or attached to each other through another element.

[0056] Throughout the specification, the expression "A and / or B" means A, B, or A and B, unless otherwise specified. That is, as used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Unless otherwise specified, the expression "C to D" means C and below D.

[0057] As used herein, the terminology is used to describe embodiments of this disclosure and is not intended to limit this disclosure.

[0058] Figure 1 This is a perspective view showing a secondary battery 1 according to an embodiment of the present disclosure, and Figure 2 This is a perspective view showing the electrode assembly 10 separated from the housing 20 according to an embodiment of the present disclosure.

[0059] like Figure 1 and Figure 2 As shown, the secondary battery 1 according to an embodiment of the present disclosure may include an electrode assembly 10, a housing 20, a lead portion 50, and a reinforcing member 70. As an example, the secondary battery 1 may further include an insulating strip 60 (see...). Figure 3 ).

[0060] According to this disclosure, by attaching the electrode assembly 10 to the secondary battery 1, thermal shrinkage of the separator can be prevented, and safety in the event of external impact can be improved. The installation of the reinforcing member 70 can increase the structural rigidity of the secondary battery 1 and improve yield.

[0061] The electrode assembly 10 includes a positive electrode plate 11, a negative electrode plate 12, and a diaphragm 13. The electrode assembly 10 can be formed as a stacked type or a core type. For example, in a stacked electrode assembly 10, the positive electrode plate 11, the negative electrode plate 12, and the diaphragm 13 are stacked (e.g., stacked alternately). Alternatively, the core type electrode assembly 10 can be formed as a roll of the negative electrode plate, the positive electrode plate, and the diaphragm 13 wound together.

[0062] The electrode assembly 10 according to an embodiment of the present disclosure is housed in a housing 20 and includes a positive electrode plate 11, a negative electrode plate 12, and a diaphragm 13 disposed between the positive electrode plate 11 and the negative electrode plate 12, and has an electrode tab 14 formed on one side (e.g., an end) in the longitudinal direction (Y-axis direction). In this disclosure, the housing 20 may be referred to as a bag.

[0063] The electrode assembly 10 can be contained in a bag along with the electrolyte. Here, the electrolyte may include lithium salts such as LiPF6 and LibF4 in organic solvents such as ethylene carbonate (EC), propylene carbonate (PC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC).

[0064] The positive electrode plate 11 can provide an electrode connector 14 electrically connected to the uncoated portion of the positive electrode, and the negative electrode plate 12 can provide an electrode connector 14 electrically connected to the uncoated portion of the negative electrode. The electrode connector 14 can be soldered to the lead portion 50 and electrically connected to the outside of the housing 20 via the lead portion 50. Insulating tape 60 (see...) Figure 3 It can be attached to the lead section 50 for insulation between the lead section 50 and the bag.

[0065] The positive electrode plate 11 may be a plate made of aluminum (Al) (e.g., aluminum foil), and a positive electrode active material made of transition metal oxide may be coated on at least one surface of the positive electrode plate 11. Additionally, an uncoated portion of the positive electrode may be provided on one side of the positive electrode plate 11, where no positive electrode active material is coated.

[0066] The negative electrode plate 12 may be a plate made of copper (Cu) or nickel (Ni), and a negative electrode active material made of graphite or carbon may be coated on at least one surface of the negative electrode plate 12. Additionally, an uncoated portion of the negative electrode may be provided on one side of the negative electrode plate 12, where no negative electrode active material is coated.

[0067] The separator 13 can be made of polyethylene (PE) or polypropylene (PP), but other materials are also possible. The separator 13 prevents electrical short circuits between the positive electrode plate 11 and the negative electrode plate 12 and allows only the movement of lithium ions.

[0068] The electrode terminals 14 extending to one side of the electrode assembly 10 along its length (Y-axis direction) include a positive electrode terminal 15 and a negative electrode terminal 16 (see...). Figure 5 Positive electrode terminal 15 is electrically connected to positive electrode plate 11, and negative electrode terminal 16 is electrically connected to negative electrode plate 12.

[0069] One side of the lead portion 50 is electrically connected to the electrode terminal piece 14, and the other side of the lead portion 50 extends to the outside of the housing 20 (see...). Figure 3 The lead portion 50 includes a positive electrode lead 52 and a negative electrode lead 54 (see...). Figure 2 Positive electrode contact 15 is electrically connected to positive electrode lead 52, and negative electrode contact 16 is electrically connected to negative electrode lead 54 (see...). Figure 5 ).

[0070] Within the technical concept of housing the electrode assembly 10, the housing 20 can be implemented in various shapes. The housing 20 can be formed in any shape that can wrap around the outside of the electrode assembly 10.

[0071] In this disclosure, a bag made of a soft film can be used as the housing 20. The bag can be formed by folding a rectangular film that extends in the longitudinal direction (Y-axis direction) to form the housing body 30 and the housing cover 40 (see...). Figure 2 ).

[0072] After the electrode assembly 10 is accommodated in the recess 34 provided in the housing body 30, the housing cover 40 is rotated to cover the open entrance of the housing body 30. In this disclosure, the bag may be in a form other than an integral form in which the housing body 30 and the housing cover 40 are formed by a single membrane. However, for ease of explanation, the following description will be exemplified by the housing body 30 and the housing cover 40 being formed by a single rectangular membrane.

[0073] Additionally, the housing body 30 may include a recess 34 and a sealing portion 32. The housing body 30 may have a recess 34 at a generally central location where the electrode assembly 10 is housed, and may include a sealing portion 32 extending generally outward from three sides of the recess 34.

[0074] The sealing portion 32 may be parallel to and connected to the surface of the housing cover 40. For example, when the housing body 30 and the housing cover 40 are formed as separate components, the sealing portion 32 may extend outward from the four sides of the recess 34. Of course, even when the housing body 30 and the housing cover 40 are formed integrally, the sealing portion 32 may extend outward from the four sides of the recess 34.

[0075] The housing cover 40 and the housing body 30 can be formed of a multilayer film, which includes a metal film and insulating layers formed on one side and the other side of the metal film, respectively. The surfaces of the housing cover 40 and the housing body 30 that are in contact with each other can be defined as inner surfaces, and the opposite surfaces can be defined as outer surfaces.

[0076] The recess 34 of the housing body 30 can be formed to a size sufficient to accommodate the electrode assembly 10 by a pressing or drawing process. The housing body 30 can be covered by the housing cover 40 at the portion forming the recess 34, and the edges of the recess 34 and the housing cover 40 can then be heat-welded to each other. After the electrode assembly 10 is accommodated in the recess 34, the bag can be sealed by sealing the edge regions of the housing body 30 and the housing cover 40.

[0077] For convenience, the edge of the housing body 30 located outside the plane centered on the edge of the housing cover 40 and the recess 34 can be defined as the sealing part 32. The inner surface of the bag can be formed with a heat-sealing layer made of heat-sealing material.

[0078] The housing cover 40 may have a rectangular flat plate shape. The housing cover 40 is connected to the housing body 30 and can be folded to cover the upper part of the housing body 30.

[0079] The reinforcing member 70 is located inside the housing 20. The reinforcing member 70 is a member mounted around the connection portion between the electrode assembly 10 and the lead portion 50, and around the edge of the electrode assembly 10 (e.g., wrapping around the connection portion between the electrode assembly 10 and the lead portion 50, and around the edge of the electrode assembly 10), and can be implemented in various shapes. The reinforcing member 70 may be a tape or film attached to the outside of the electrode assembly 10, and may include an adhesive and a synthetic resin selected from polyethylene terephthalate (PET), polypropylene (PP), and polyimide (PI), the adhesive being applied to the synthetic resin. Additionally, the reinforcing member 70 may have a plurality of holes formed to allow electrolyte movement. For example, the reinforcing member 70 may include a first reinforcing member 80, a second reinforcing member 100, a third reinforcing member 110, and a fourth reinforcing member 120.

[0080] Figure 2 Show Figure 1 The secondary battery 1 is flipped and opened. Additionally, Figure 2 The diagram shows the state of the lead portion 50 before it is bent into a "V" shape. The bending of the lead portion 50 is performed with the upper part of the electrode assembly 10 and a portion of the lead portion 50 covered by the first reinforcing member 80, which will be described later. That is, the exterior of a portion of the lead portion 50 and the electrode tab 14 are covered by the first reinforcing member 80. With the first reinforcing member 80 installed, the lead portion 50 is bent to position itself between the housing cover 40 and the sealing portion 32. Accordingly, the electrode tab 14 and the lead portion 50 are bent into a "V" shape.

[0081] The portion containing the electrode terminals 14 in the electrode assembly 10 is defined as the upper part of the electrode assembly 10. The upper part of the electrode assembly 10 is located on one side along the length of the electrode assembly 10.

[0082] Figure 3 This is a front cross-sectional view of a secondary battery 1 according to an embodiment of the present disclosure. Figure 3 As shown, the first reinforcing member 80 is mounted in a shape that can wrap around the edge of the electrode assembly 10 and around the connection portion and lead portion 50 of the electrode assembly 10 on one side (e.g., the first side) in the longitudinal direction (Y-axis direction) of the electrode assembly 10. For example, the connection portion of the electrode assembly 10 is the portion connected between the electrode assembly 10 and the lead portion 50. In addition, the first reinforcing member 80 is mounted in a shape that can wrap around the end of the electrode assembly 10 that is connected to the electrode terminal block 14.

[0083] The first reinforcing member 80 can be formed by attaching a strap to wrap around the upper part of the electrode assembly 10. The first reinforcing member 80 can protect the exposed portion of the diaphragm 13, the electrode terminals 14, and the lead portions 50 soldered to the electrode terminals 14. When the first reinforcing member 80 is mounted on the electrode assembly 10, the length of the first reinforcing member 80 covering the electrode assembly 10 can be configured so as not to exceed half (1 / 2) of the total length of the electrode assembly 10 in the longitudinal direction (Y-axis direction).

[0084] The first reinforcing member 80 may include multiple members, and for example, the first reinforcing member 80 may include a first base 81 and a first cover 82. The first cover 82 and the first base 81 are fixed in a state of contact with each other, and the electrode assembly 10 is located between the first cover 82 and the first base 81.

[0085] The first base 81 contacts the lower side 18 of the electrode assembly 10 and is mounted in a shape that can wrap around the lower part of the electrode tab 14 and the lead portion 50. The first base 81 may be made of tape or film and can be fixed in a state of contact with the electrode assembly 10, the electrode tab 14, and the lead portion 50 by including an adhesive component. The first base 81 may have a width (X-axis) length that is the same as the width (X-axis) length of the electrode assembly 10. One side of the first base 81 may contact the lower side 18 of the electrode assembly 10, and the other side of the first base 81 may contact the lower part of the lead portion 50. The adhesive component used for the first base 81 may be a conductive epoxy resin, thermosetting resin, or UV-curable resin that ensures a strong bond with the electrode assembly 10.

[0086] The first cover 82 contacts the upper side 17 and the first base 81 of the electrode assembly 10, and is a component that wraps around the upper edge of the electrode assembly 10 together with the first base 81, and can be implemented in various shapes. The first cover 82 can be made of tape or film. The first cover 82 can have the same width direction (X-axis direction) length as the electrode assembly 10. One side of the first cover 82 can contact the upper side 17 of the electrode assembly, and the other side of the first cover 82 can contact the lower part of the lead portion 50. By including an adhesive component, the first cover 82 can be fixed in a state of contact with the electrode assembly 10, the electrode tab 14, and the lead portion 50. The adhesive components used for the first cover 82 and the first base 81 are the same or interchangeable, thereby providing consistent bonding strength. The first cover 82 and the first base 81 can have the same length in the width direction (X-axis direction).

[0087] The insulating tape 60 can be located between the lead portion 50 and the housing 20, and can be fixed to the outside of the lead portion 50 and can be implemented as a component of various shapes. The insulating tape 60 can be installed on each side of the lead portion 50 facing the housing 20. The insulating tape 60 is made of an insulating material such as polyimide (PI), polyester (PET) or polypropylene (PP), and by installing the insulating tape 60, the electrical connection between the lead portion 50 and the housing 20 can be blocked.

[0088] Figure 4 This is a front cross-sectional view showing the state in which the reinforcing member 70 is fixed to the housing 20 according to an embodiment of the present disclosure. Figure 4As shown, the first base 81 can be fixed to the underside of the housing 20. For example, a first reinforcing member 80 is mounted on the underside of the housing 20 and may include a fixing layer 84 containing adhesive components. The fixing layer 84 may include an adhesive such as a conductive epoxy resin, thermosetting resin, or UV-curable resin, and the adhesive provides high adhesive strength and excellent heat resistance to stably fix the first base 81 to the housing 20. The fixing layer 84 may be on the underside of the first base 81. The fixing layer 84 can fix the first base 81 to the housing 20. The upper side of the first base 81 is fixed to the electrode assembly 10, and its lower side is fixed to the housing 20, and thus excessive movement of the electrode assembly 10 within the housing 20 can be suppressed.

[0089] The first reinforcing member 80 may include an insulating portion 85 serving as an insulating strip. The insulating portion 85 is made of an insulating material and extends between the lead portion 50 and the housing 20. Additionally, the insulating portion 85 is secured to the housing 20 by an adhesive component. The insulating portion 85 may be made of an insulating material such as polyimide (PI), polyester (PET), or polypropylene (PP) that provides high insulation and heat resistance to enhance battery safety. The insulating portion 85 may be attached to the first base 81 and the first cover 82, or integrally formed therewith.

[0090] Figure 5 This is a cross-sectional view showing the upper side of the reinforcing member 70 in the secondary battery 1 according to an embodiment of the present disclosure, and Figure 6 This is a cross-sectional view showing the lower side of the reinforcing member 70 in the secondary battery 1 according to an embodiment of the present disclosure (e.g., a cross-sectional view showing the lower side of the reinforcing member 70). Figure 5 (Flip 180 degrees). For example... Figure 5 and Figure 6 As shown, the first reinforcing member 80 can be installed by wrapping around the positive electrode tab 15 and negative electrode tab 16 of the electrode assembly 10 using a single member. A single strip / film extending in the width direction (X-axis direction) of the electrode assembly 10 covers the upper side of the positive electrode tab 15 and negative electrode tab 16 of the electrode assembly 10, and a corresponding other single strip / film covers the lower side of the positive electrode tab 15 and negative electrode tab 16 of the electrode assembly 10.

[0091] The second reinforcing member 100 wraps around the edge of the electrode assembly 10 on the other side (e.g., the second side) in the longitudinal direction (Y-axis direction) of the electrode assembly 10, and can be implemented in various shapes. For example, the second reinforcing member 100 may have a lower band attached to wrap around the lower part of the electrode assembly 10. The second reinforcing member 100 may be mounted to be no more than half (1 / 2) of the total longitudinal direction (Y-axis direction) length of the electrode assembly 10. The width direction (X-axis direction) length of the second reinforcing member 100 may be equal to the width direction length of the electrode assembly 10.

[0092] The third reinforcing member 110 wraps around the edge of the electrode assembly 10 on one side in the width direction (X-axis direction) and can be implemented in various shapes. The third reinforcing member 110 can be installed to be no more than half (1 / 2) of the total width direction (X-axis direction) length of the electrode assembly 10, and its length in the length direction (Y-axis direction) can be equal to the length direction length of the electrode assembly 10.

[0093] The fourth reinforcing member 120 wraps around the edge of the electrode assembly 10 on the other side in the width direction (X-axis direction) and can be implemented in various shapes. The fourth reinforcing member 120 is installed such that it does not exceed half (1 / 2) of the total width direction (X-axis direction) of the electrode assembly 10, and its length direction (Y-axis direction) can be equal to the length direction (Y-axis direction) of the electrode assembly 10.

[0094] Figure 7 This is a front view showing the state in which the first cover 82 is mounted on the upper side and the first base 81 is mounted on the lower side in the electrode assembly 10 according to an embodiment of the present disclosure. Figure 8 This is a front view showing the state in which the work roller 140, according to an embodiment of the present disclosure, presses down the first cover 82 during movement. Figure 9 This is a plan view showing the reinforcing member 70 and the work roller 140 according to an embodiment of the present disclosure. Figures 7 to 9 As shown, the first base 81 and the first cover 82 can form a first reinforcing member 80 by means of an upper clamp 150, a lower clamp 160 and a working roller 140.

[0095] One side of the first cover 82 can be fixed to the upper side of the electrode assembly 10. The first cover 82 is fixed in contact with the upper side 17 of the electrode assembly, and the upper clamp 150 presses the first cover 82 toward the electrode assembly 10. The other side of the first cover 82 extends laterally and protrudes outward from the electrode assembly 10.

[0096] One side of the first base 81 can contact the lower side 18 of the electrode assembly, and the other side of the first base 81 extends laterally. The lower part of the first base 81 is supported by the lower clamp 160.

[0097] The work roller 140 changes the shape of the first cover 82 by applying pressure to the first cover 82 that protrudes outward from the electrode assembly 10. When the work roller 140 applies pressure to the first cover 82 downward, the first cover 82 bends into a shape that can wrap around the end of the electrode assembly 10.

[0098] Additionally, the work roller 140 applies pressure to the first cover 82 while moving laterally on the upper side of the lead portion 50 or the electrode terminal piece 14 connected to the lead portion 50. In this process, the first base portion 81 and the first cover 82 can be joined by the work roller 140.

[0099] Figure 10 This is a cross-sectional view showing the upper side of the reinforcing member 70 in a secondary battery 1 according to another embodiment of the present disclosure, and Figure 11 This is a plan view showing the reinforcing member 70 and the work roller 140 according to another embodiment of the present disclosure. Figure 10 and Figure 11 As shown, the first reinforcing member 90 may include a first reinforcing sub-member 92 covering the positive electrode terminal 15 of the electrode assembly 10 (e.g., surrounding the positive electrode terminal 15 of the electrode assembly 10) and a second reinforcing sub-member 94 covering the negative electrode terminal 16 of the electrode assembly 10 (e.g., surrounding the negative electrode terminal 16 of the electrode assembly 10). In some examples, the first reinforcing sub-member 92 and the second reinforcing sub-member 94 may be installed in a spaced-apart state.

[0100] The first reinforcing sub-component 92 may be mounted in a shape that can wrap around the upper edge of the electrode assembly 10 and the positive electrode tab 15, as well as a portion of the positive electrode lead 52. The first reinforcing sub-component 92 may include two strips and is configured to be coupled to each other by the electrode assembly 10 disposed between the two strips, and its detailed construction is similar to or the same as that of the first reinforcing member 90, and therefore its detailed description is omitted.

[0101] The second reinforcing sub-component 94 can be mounted in a shape that can wrap around the upper edge of the electrode assembly 10 and the negative electrode tab 16, as well as a portion of the negative electrode lead 54. The second reinforcing sub-component 94 may include two strips and is configured to be coupled to each other by the electrode assembly 10 disposed between the two strips, and its detailed construction is similar to or the same as that of the first reinforcing component 90, and therefore its detailed description is omitted.

[0102] Because the first reinforcing component 92 and the second reinforcing component 94 are installed spaced apart from each other, the electrolyte can move more smoothly into the electrode assembly 10 through the separated space, thereby improving the ion conductivity of the battery and increasing the charging / discharging efficiency. Furthermore, because the electrolyte can be uniformly distributed within the electrode assembly 10, the electrochemical performance of the battery can be maintained more stably.

[0103] Figure 12 This is a cross-sectional view showing the upper side of the reinforcing member 70 in a secondary battery 1 according to another embodiment of the present disclosure, and Figure 13This is a cross-sectional view showing the lower side of the reinforcing member 70 in a secondary battery 1 according to another embodiment of the present disclosure. Figure 12 and Figure 13 As shown, to reinforce the structural rigidity of the reinforcing member 70, separate reinforcing strips may be additionally installed. For example, the reinforcing member 70 may be installed to wrap around at least one side of the upper and lower sides of the electrode assembly 10, the connecting portion and the lead portion 50 of the electrode assembly 10, and the periphery of the edge of the electrode assembly 10. For example, the connecting portion of the electrode assembly 10 is the portion connecting the electrode assembly 10 and the lead portion 50. The reinforcing member 70 may further include a fifth reinforcing member 130.

[0104] For example, the fifth reinforcing member 130 can be mounted in a shape that can wrap around the underside of the electrode assembly 10, protecting the underside of the electrode assembly 10 and dispersing the pressure applied to the electrode assembly 10, thereby improving battery durability. The fifth reinforcing member 130 can be mounted to overlap at least one of the first reinforcing member 80, the second reinforcing member 100, the third reinforcing member 110, and the fourth reinforcing member 120 on the underside 18 of the electrode assembly 10, increasing the bonding strength between the reinforcing members and thus strengthening the overall structural integrity of the battery. Additionally, the fifth reinforcing member 130 forms an additional protective layer beneath the electrode assembly 10 to increase resistance to external impacts.

[0105] Figure 14 This is a cross-sectional view showing the upper side of the reinforcing member 70 in a secondary battery 1 according to another embodiment of the present disclosure, and Figure 15 This is a cross-sectional view showing the lower side of the reinforcing member 70 in a secondary battery 1 according to another embodiment of the present disclosure. Figure 14 and Figure 15 As shown, the reinforcing member 70 includes a first reinforcing member 90, a second reinforcing member 100, a third reinforcing member 110, a fourth reinforcing member 120, and a fifth reinforcing member 130. The first reinforcing member 90 includes a first reinforcing sub-member 92 and a second reinforcing sub-member 94 spaced apart from each other, and is used to improve the mobility of the electrolyte.

[0106] The fifth reinforcing member 130 covers the lower surface of the electrode assembly 10, strengthens the bond strength between the reinforcing members 70, and increases resistance to external impacts.

[0107] The first reinforcing sub-component 92, the second reinforcing sub-component 94, and the fifth reinforcing sub-component 130 have been described above, and therefore their detailed descriptions are omitted.

[0108] The electrode assembly 10 of this disclosure will now be described in more detail.

[0109] As the positive electrode active material, compounds capable of reversibly inserting / deintercalating lithium (e.g., lithiation intercalation compounds) can be used. For example, at least one of lithium and a composite oxide of a metal selected from cobalt, manganese, nickel, and combinations thereof can be used.

[0110] The composite oxide can be a lithium transition metal composite oxide, and examples of it can include lithium nickel-based oxides, lithium cobalt-based oxides, lithium manganese-based oxides, lithium iron phosphate-based compounds, cobalt-free nickel manganese-based oxides, or combinations thereof.

[0111] As an example, a compound represented by any of the following formulas can be used: Li a A 1-b XbO 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni 1-b-c Mn b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni b Co c L 1 d G e O2(0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, O≤e≤0.1); Li a NiG b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoG b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-b G b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2Gb O4 (0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a Mn 1-g G g PO4 (0.90 ≤ a ≤ 1.8, 0 ≤ g ≤ 0.5); Li (3-f) Fe2(PO4)3 (0 ≤ f ≤ 2); Li a FePO4 (0.90 ≤ a ≤ 1.8).

[0112] In the above formula: A is Ni, Co, Mn or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements or a combination thereof; D is O, F, S, P or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V or a combination thereof; and L1 is Mn, Al or a combination thereof.

[0113] The positive electrode for a lithium secondary battery may include a current collector and a positive electrode active material layer formed on the current collector. The positive electrode active material layer may include a positive electrode active material, and may further include a binder and / or a conductive material.

[0114] Based on 100 wt% of the positive electrode active material layer, the content of the positive electrode active material is in the range of about 90 wt% to about 99 wt%, and based on 100 wt% of the positive electrode active material layer, the contents of the binder and the conductive material are respectively in the range of about 0.5 wt% to about 5 wt%.

[0115] The current collector may be aluminum (Al) foil, but is not limited thereto.

[0116] The negative electrode active material may include a material capable of reversibly intercalating / deintercalating lithium ions, lithium metal, an alloy of lithium metal, a material capable of doping and undoping lithium, or a transition metal oxide.

[0117] The material capable of reversibly intercalating / deintercalating lithium ions may be a carbon-based negative electrode active material, which may include, for example, crystalline carbon, amorphous carbon or a combination thereof. Examples of crystalline carbon may include graphite such as natural graphite or artificial graphite, and examples of amorphous carbon may include soft carbon, hard carbon, pitch carbide, mesophase pitch carbide, sintered coke, etc.

[0118] Si-based negative electrode active material or Sn-based negative electrode active material may be used as a material capable of doping and undoping lithium. The Si-based negative electrode active material may be silicon, a silicon-carbon composite, SiOx (0 < x ≤ 2, for example, SiO2), a Si-based alloy or a combination thereof.

[0119] The silicon-carbon composite can be a composite of silicon and amorphous carbon. According to one embodiment, the silicon-carbon composite can be in the form of silicon particles and amorphous carbon coated on the surface of the silicon particles.

[0120] The silicon-carbon composite may further include crystalline carbon. For example, the silicon-carbon composite may include a core comprising crystalline carbon and silicon particles, and an amorphous carbon coating on the surface of the core.

[0121] The negative electrode for a lithium secondary battery may include a current collector and a layer of negative electrode active material disposed on the current collector. The negative electrode active material layer may include a negative electrode active material and may further include a binder and / or a conductive material.

[0122] For example, the negative electrode active material layer may include about 90 wt% to about 99 wt% of negative electrode active material, about 0.5 wt% to about 5 wt% of binder, and about 0 wt% to about 5 wt% of conductive material.

[0123] Non-aqueous binders, aqueous binders, dry binders, or combinations thereof can be used as binders. When an aqueous binder is used as a negative electrode binder, it may further include cellulose compounds capable of imparting viscosity.

[0124] As the negative electrode substrate, one can be selected from copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, polymer substrate coated with conductive metal, and combinations thereof.

[0125] Electrolytes used in lithium secondary batteries may include non-aqueous organic solvents and lithium salts.

[0126] Non-aqueous organic solvents can act as a medium through which ions participating in the electrochemical reactions of the battery can move.

[0127] Non-aqueous organic solvents can be carbonate-based solvents, ester-based solvents, ether-based solvents, ketone-based solvents, alcohol-based solvents, or aprotic solvents, and can be used alone or in combination of two or more.

[0128] In addition, when using carbonate-based solvents, a mixture of cyclic carbonates and chain carbonates can be used.

[0129] Depending on the type of lithium-ion secondary battery, a separator can be present between the first electrode plate (e.g., the negative electrode) and the second electrode plate (e.g., the positive electrode). Polyethylene, polypropylene, polyvinylidene fluoride, or multilayer films of two or more layers thereof can be used as the separator.

[0130] The diaphragm may include a porous substrate and a coating on one or both surfaces of the porous substrate, comprising organic materials, inorganic materials, or combinations thereof.

[0131] Organic materials may include polyvinylidene fluoride polymers or (meth)acrylic acid polymers.

[0132] Inorganic materials may include, but are not limited to, inorganic particles selected from Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite and combinations thereof.

[0133] Organic and inorganic materials can be mixed in a coating, or they can be in the form of coatings containing organic materials and coatings containing inorganic materials stacked on top of each other.

[0134] The battery according to the above embodiments can be used to manufacture battery packs. Figure 16A and Figure 16B This is a perspective view showing a battery pack including an exemplary secondary battery according to this disclosure. Reference Figure 16A and Figure 16B The battery pack 300 may include a plurality of battery modules 200 and a housing 310 housing the plurality of battery modules 200. For example, the housing 310 may include a first housing 311 and a second housing 312 connected in a facing direction, with the plurality of battery modules 200 disposed therebetween. The plurality of battery modules 210 may be electrically connected to each other using busbars 251, and the plurality of battery modules 200 may be electrically connected in series / parallel or a mixed series-parallel manner to obtain the desired electrical output. In the figures, for convenience, components such as busbars, cooling units, and external terminals for electrical connections to individual battery cells are omitted. In some embodiments, the battery pack 300 may be mounted on a vehicle. The vehicle may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle may include four-wheeled vehicles and two-wheeled vehicles.

[0135] Figure 17A and Figure 17B These are perspective and side views of a vehicle 400 and a vehicle 500, respectively, including a battery pack 300 (exemplary) according to the present disclosure.

[0136] exist Figure 17A In this configuration, the battery pack 300 may include: a battery pack cover 311, which is part of the vehicle floor 410 and may correspond to a first housing; and a battery pack frame 312, which is positioned below the vehicle floor 410 and may correspond to a second housing. The battery pack cover 311 and the battery pack frame 312 may be structurally integrated with the vehicle floor 420. The vehicle floor 410 separates the interior and exterior of the vehicle, and the battery pack frame 312 may be positioned on the exterior of the vehicle.

[0137] like Figure 17BAs shown, vehicle 500 can be assembled with additional components such as a hood 510 at the front of the vehicle body and fenders 520 at the front and rear of the vehicle. Vehicle 500 includes a battery pack 300, which includes a battery pack cover 311 and a battery pack frame 312, and the battery pack 300 can be attached to the body of vehicle 500.

[0138] Although several embodiments of the present disclosure have been shown and described, those skilled in the art will understand that various changes and modifications can be made to these embodiments without departing from the principles and technical ideas of the present disclosure.

[0139] This document has disclosed exemplary embodiments, and although specific terminology has been used, it is used and interpreted in a general and descriptive sense only and is not intended to be limiting. In some instances, as will be apparent to those skilled in the art at the time of filing this application, unless otherwise specifically indicated, features, characteristics, and / or elements described in connection with particular embodiments may be used alone or in combination with features, characteristics, and / or elements described in connection with other embodiments. Accordingly, those skilled in the art will understand that various changes in form and detail may be made without departing from the spirit and scope of the invention as set forth in the following claims.

Claims

1. A secondary battery, comprising: Electrode assembly, including positive electrode plate, negative electrode plate and diaphragm; The lead portion is electrically connected to the electrode assembly; Housing that houses the electrode assembly; as well as A reinforcing member, inside the housing, surrounds the electrode assembly at the connection portion between the electrode assembly and the lead portion, and at the edges of the lead portion and the electrode assembly.

2. The secondary battery according to claim 1, wherein, The positive electrode plate, the negative electrode plate, and the diaphragm are stacked or wound together.

3. The secondary battery according to claim 1, wherein, The reinforcing member includes a strip or membrane attached to the outside of the electrode assembly.

4. The secondary battery according to claim 3, wherein, The reinforcing component includes an adhesive and a synthetic resin, wherein the synthetic resin is selected from polyethylene terephthalate, polypropylene, and polyimide.

5. The secondary battery according to any one of claims 1 to 3, wherein, The reinforcing components include: A first reinforcing member wraps around the edge of the electrode assembly, the connecting portion of the electrode assembly, and the lead portion on a first side in the longitudinal direction of the electrode assembly. A second reinforcing member wraps around the edge of the electrode assembly on a second side in the length direction of the electrode assembly; A third reinforcing member wraps around the edge of the electrode assembly on one side in the width direction; and A fourth reinforcing member wraps around the edge of the electrode assembly on the other side of the electrode assembly in the width direction.

6. The secondary battery according to claim 5, wherein, The first reinforcing member includes: The first base contacts the lower side of the electrode assembly; and A first cover contacts the upper side of the electrode assembly and the first base, and the first cover, together with the first base, wraps around the upper edge of the electrode assembly.

7. The secondary battery according to claim 6, wherein, The first reinforcing member further includes a fixing layer on the lower side of the first base, the fixing layer having an adhesive component and being fixed to the housing.

8. The secondary battery according to claim 6, wherein: One side of the first cover is fixed to the upper side of the electrode assembly, and The first cover is pressed by a work roller to be bonded to the first base.

9. The secondary battery according to claim 5, wherein, The first reinforcing member further includes an insulating portion comprising an insulating material that extends between the lead portion and the housing and is fixed to the housing by an adhesive component.

10. The secondary battery according to claim 5, wherein, The first reinforcing member includes: A first reinforcing sub-component covers the positive electrode terminal of the electrode assembly; and The second reinforcing sub-component covers the negative electrode terminal piece of the electrode assembly. The first reinforcing sub-component and the second reinforcing sub-component are spaced apart from each other.

11. A secondary battery, comprising: Electrode assembly, including positive electrode plate, negative electrode plate and diaphragm; The lead portion is electrically connected to the electrode assembly; Housing that houses the electrode assembly; as well as A reinforcing member, inside the housing, surrounds the electrode assembly at the connection portion between the electrode assembly and the lead portion, the edge of the lead portion and the electrode assembly, and at least one of the upper and lower sides of the electrode assembly.

12. The secondary battery according to claim 11, wherein, The reinforcing components include: A first reinforcing member wraps around the edge of the electrode assembly, the connecting portion of the electrode assembly, and the lead portion on a first side in the longitudinal direction of the electrode assembly. A second reinforcing member wraps around the edge of the electrode assembly on a second side in the length direction of the electrode assembly; A third reinforcing member wraps around the edge of the electrode assembly on one side in the width direction; A fourth reinforcing member, on the other side of the electrode assembly in the width direction, wraps around the edge of the electrode assembly; and A fifth reinforcing member is wrapped around at least one of the upper and lower sides of the electrode assembly.

13. The secondary battery according to claim 12, wherein, The first reinforcing member comprises a single reinforcing member that wraps around the positive electrode terminal and the negative electrode terminal of the electrode assembly.

14. The secondary battery according to claim 12, wherein, The first reinforcing member includes: The first reinforcing component surrounds the positive electrode terminal of the electrode assembly; and The second reinforcing sub-component wraps around the negative electrode terminal of the electrode assembly. The first reinforcing sub-component and the second reinforcing sub-component are spaced apart from each other.

15. The secondary battery according to claim 12, wherein, The first reinforcing member includes: A first base portion contacts the lower side of the electrode assembly; and A first cover contacts the upper side of the electrode assembly and the first base, and the first cover, together with the first base, wraps around the upper edge of the electrode assembly.

16. The secondary battery according to claim 15, wherein, The first reinforcing member further includes a fixing layer on the lower side of the first base, the fixing layer having an adhesive component and being fixed to the housing.

17. The secondary battery according to claim 12, wherein, The first reinforcing member further includes an insulating portion comprising an insulating material that extends between the lead portion and the housing and is fixed to the housing by an adhesive component.

18. The secondary battery according to claim 12, wherein, The fifth reinforcing member wraps around the lower side of the electrode assembly.

19. The secondary battery according to any one of claims 12 to 18, wherein, The fifth reinforcing member overlaps with at least one of the first to fourth reinforcing members.

20. The secondary battery according to any one of claims 11 to 18, wherein, The reinforcing component includes an adhesive and a synthetic resin, wherein the synthetic resin is selected from polyethylene terephthalate, polypropylene, and polyimide.

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