Secondary battery

Abstract

The present disclosure relates to a secondary battery, and the technical problem to be solved is to provide a secondary battery which is advantageous in terms of optimized electrolyte utilization and safety by inserting a separator into an empty space between a case and an electrode assembly to minimize an ineffective space. To this end, the present disclosure provides a secondary battery comprising: an electrode assembly; a case accommodating the electrode assembly and having at least one opening; a cap assembly coupled through the opening to seal the housing; and at least one first spacer in contact with one side of the electrode assembly and one side of the case so as to be interposed in a space between the electrode assembly and the case, and formed in a shape corresponding to a shape of the space between the electrode assembly and the case.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a secondary battery. Background Art

[0002] Unlike a primary battery that cannot be charged, a secondary battery is a battery that can be charged and discharged. Low-capacity batteries are used in portable small electronic devices (such as smart phones or digital cameras), and high-capacity batteries in the form of modules connecting dozens to hundreds of battery packs are widely used as a power source for driving motors in hybrid vehicles, electric vehicles, or drones or as energy storage devices.

[0003] Such a rechargeable secondary battery includes an electrode assembly having a separator between a positive electrode plate and a negative electrode plate, a current collector plate electrically connected to the electrode assembly, a terminal electrically connected to the current collector plate, a case accommodating the electrode assembly and the current collector plate, and a cover plate that closes the case and connects the terminal to the cover plate while passing through the cover plate.

[0004] An ineffective space may occur between the electrode assembly and the case, which is an empty space. The electrolyte remaining in the ineffective space inside the cell does not participate in the electrochemical reaction, resulting in low availability. In addition, since the electrolyte must be injected into the cell including the void volume, the amount of the electrolyte needs to be increased. In addition, due to the empty space inside the cell, deformation may occur in the electrode assembly during collision or vibration.

[0005] The above-described information disclosed in the background art of the present invention is only for enhancing the understanding of the background art of the present disclosure, and thus may include information that does not constitute the related art. Summary of the Invention

[0006] Technical Problem

[0007] The present disclosure provides a secondary battery that is advantageous in terms of optimized electrolyte utilization and cell safety by minimizing the empty space between the case and the electrode assembly.

[0008] However, the technical problems to be solved by the present invention are not limited to those described above, and other problems not mentioned can be clearly understood by those skilled in the art from the description of the present disclosure provided below.

[0009] Technical Solution

[0010] A secondary battery for solving the above technical problems according to an embodiment of the present disclosure includes: an electrode assembly; a housing that houses the electrode assembly and has at least one opening; a cover assembly that is coupled through the opening to seal the housing; and at least one first spacer that contacts one side of the electrode assembly and one side of the housing to be in the space between the electrode assembly and the housing, wherein the first spacer is formed in a shape corresponding to the shape of the space between the electrode assembly and the housing.

[0011] The electrode assembly may include a first electrode and a second electrode, each of the first electrode and the second electrode includes an electrode plate and an electrode uncoated portion, and the electrode uncoated portion of the first electrode and the electrode uncoated portion of the second electrode may protrude in at least one direction of the direction toward the cover assembly and the direction opposite to the cover assembly.

[0012] The first spacer may be formed as a pair on both sides of the electrode assembly, and the electrode uncoated portion of the first electrode and the electrode uncoated portion of the second electrode do not protrude on both sides of the electrode assembly.

[0013] The electrode assembly may be a plurality of electrode assemblies.

[0014] The secondary battery may further include at least one second spacer that contacts one surface of the plurality of electrode assemblies and is in the space between the plurality of electrode assemblies.

[0015] The second spacer may be formed in a shape corresponding to the shape of the space between the plurality of electrode assemblies.

[0016] The second spacer may be formed as a pair on both sides of each of the plurality of electrode assemblies, and the electrode uncoated portion of the first electrode and the electrode uncoated portion of the second electrode do not protrude on both sides of each of the plurality of electrode assemblies.

[0017] In the plurality of electrode assemblies, the electrode uncoated portion of the first electrode and the electrode uncoated portion of the second electrode may protrude in the same direction.

[0018] The first spacer and the second spacer may be formed to be separated from each other.

[0019] The first spacer and the second spacer may be integrally formed.

[0020] At least one of the first spacer and the second spacer may have an empty internal space.

[0021] At least one of the first spacer and the second spacer may be coupled to the interior of the housing.

[0022] Further includes a fixing member surrounding the sides of the plurality of electrode assemblies positioned in series.

[0023] At least one of the first spacer and the second spacer may be coupled to the plurality of electrode assemblies through the fixing member.

[0024] The first spacer and the second spacer may be made of an insulating material.

[0025] The uncoated portion of the electrode of the first electrode and the uncoated portion of the electrode of the second electrode may be spaced apart from each other and may protrude from the electrode plate toward the lid assembly.

[0026] The electrode assembly may be wound in a wound type.

[0027] Advantageous Effects

[0028] According to an embodiment of the present disclosure, by inserting a spacer into the empty space between the housing and the electrode assembly to minimize the void space, the electrolyte utilization rate can be optimized, and collisions or deformations caused by the empty space inside the monomer can be prevented, thereby improving safety. In addition, the spacer can be used as a guide during the assembly of the monomer, thus facilitating the assembly process.

[0029] However, the effects that can be achieved through the present disclosure are not limited to the effects mentioned above, and those skilled in the art can clearly understand other technical effects not mentioned from the description of the present invention described below. Brief Description of the Drawings

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

[0031] Figure 2 is a perspective view showing Figure 1 a partial configuration of the secondary battery.

[0032] Figure 3 is a cross-sectional view taken along line 3-3' of the secondary battery Figure 1 shown.

[0033] Figure 4 is a cross-sectional view of a secondary battery including one electrode assembly according to an embodiment.

[0034] Figure 5 is a cross-sectional view of a secondary battery including a plurality of electrode assemblies according to an embodiment.

[0035] Figure 6A cross-sectional view of a secondary battery including an empty spacer according to an embodiment.

[0036] Figure 7 A perspective view showing a state in which a spacer of a secondary battery according to an embodiment is coupled to a case.

[0037] Figure 8 A perspective view showing a state in which a spacer is coupled by a fixing member of a secondary battery according to an embodiment. Detailed Description

[0038] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Before describing the present disclosure, terms or words used in this specification and claims should not be construed restrictively as general or dictionary meanings, and should be construed as meanings and concepts consistent with the technical concept of the present invention based on the principle that the inventor can appropriately define terms to best describe his or her invention. Therefore, the embodiments described in this specification and the configurations shown in the drawings are only some of the most preferred embodiments of the present disclosure and do not represent all the technical spirits of the present disclosure. Thus, it should be understood that various equivalents and modifications that can replace these may exist at the time of filing this application.

[0039] In addition, as used herein, the terms "comprising" and / or "including" when used in this specification clearly specify the presence of the stated features, quantities, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, quantities, steps, operations, elements, components, and / or groups thereof.

[0040] In addition, for a better understanding of the present disclosure, the drawings may not be drawn to scale, and the dimensions of some components may be enlarged. In addition, in different embodiments, the same reference numerals may be assigned to the same components.

[0041] Referring to two comparable objects as "the same" means that they are "substantially the same". Thus, the phrase "substantially the same" may include cases having a deviation considered to be low in the art (e.g., a deviation of 5% or less). In addition, a certain parameter being uniform in a predetermined region may mean that the parameter is uniform in terms of the average value.

[0042] Although terms such as "first", "second", etc. may be used to describe various elements, these elements should not be limited by these terms. These terms may be used only to distinguish one element from another, and unless otherwise specifically stated, the first element may also be the second element.

[0043] Throughout the specification, unless otherwise stated, each element may be singular or plural.

[0044] Arranging any element "above (or below)" or "on (under)" another element may mean that the any element can be set to contact the upper (or lower) surface of the element, and another element can also be interposed between the element and the any element disposed on (or under) the element.

[0045] In addition, it will be understood that when a component is referred to as being "on", "connected to", or "coupled to" another component, these components can be directly linked or connected to each other, but another component can be "interposed" between the components, or the respective components can also be "linked", "coupled", or "connected" through another component.

[0046] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. In addition, when describing embodiments of the present disclosure, the use of "may" relates to "one or more embodiments of the present disclosure". Expressions such as "one or more" before a list of elements modify the entire list of elements, rather than individual elements in the list.

[0047] Throughout the specification, when referring to "A and / or B", this means A, B, or A and B, unless otherwise specified, and when referring to "C to D", this means it is greater than C and less than D, unless otherwise specified.

[0048] When the phrases "at least one of A, B, and C", "at least one of A, B, or C", "at least one selected from the group consisting of A, B, and C", or "at least one selected from A, B, and C" are used to specify a list of elements A, B, and C, the phrase can refer to any and all suitable combinations.

[0049] The term "use" can be considered synonymous with the term "utilize". As used herein, the terms "substantially", "about", and similar terms are used as approximate terms, rather than terms of degree, and are intended to account for the inherent variations in measured or calculated values as would be recognized by a person of ordinary skill in the art.

[0050] It will be understood that although terms such as first, second, etc. may be used herein to describe various components, elements, regions, layers, and / or sections, these components, elements, layers, and / or sections should not be limited by these terms. These terms are only used to separate one component, element, region, layer, and / or section from another component, element, region, layer, and / or section. Thus, for example, without departing from the teachings of the present disclosure, the first component, first element, first region, first layer, and / or first section discussed below can be referred to as the second component, second element, second region, second layer, and / or second section.

[0051] As illustrated in the figures, for ease of describing the relationship of one element or feature to another element or feature, spatial relative terms such as "below", "beneath", "under", "above", "on" etc. may be used herein. It will be understood that the spatial relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if an element or feature in the figures is flipped, the element described as "below" or "beneath" other elements or features will then be oriented "above" or "on" the other elements or features. Thus, the exemplary term "below" can encompass both an upper and a lower orientation.

[0052] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the disclosure.

[0053] Hereinafter, in an exemplary embodiment of a prismatic battery according to an embodiment of the present disclosure, one of the prismatic batteries is selected, and the selected battery is described as having a general structure, and in the case of general application technology, the general structure of the prismatic battery will be described. However, the present disclosure is not limited thereto, and the housing may be configured in various shapes such as a circular shape or a pouch shape. Additionally, the housing may be made of a metal such as aluminum, aluminum alloy or nickel-plated steel, or made of a laminated film or plastic that constitutes a pouch.

[0054] Figure 1 is a perspective view showing a secondary battery according to an embodiment of the present disclosure, and Figure 2 is showing Figure 1 an exploded perspective view of a partial configuration of the secondary battery.

[0055] Referring to Figure 1 and Figure 2 , a secondary battery 100 according to an embodiment may include an electrode assembly 110, spacers 120, 130, a housing 150, and a cover assembly 160.

[0056] The electrode assembly 110 may be formed by winding or stacking a laminate of a first electrode plate, a separator, and a second electrode plate formed in a thin plate or film shape. However, in one embodiment, the electrode assembly 110 may be formed by winding in a wound type. The electrode assembly 110 may have a winding axis parallel to the longitudinal direction (e.g., the y direction) of the housing 150. Additionally, the electrode assembly 110 may be accommodated inside the housing 150 by stacking one or more electrode assemblies 110 such that their long side portions are adjacent to each other. In the present disclosure, the number of the electrode assemblies 110 is not limited. Here, the first electrode plate may operate with a first polarity (e.g., as a positive electrode), and the second electrode plate may operate with a second polarity (e.g., as a negative electrode). Of course, the first electrode plate and the second electrode plate may be arranged with different polarities according to the choice of those skilled in the art.

[0057] The first electrode plate is formed by applying a first electrode active material such as a transition metal oxide to a first electrode current collector formed of a metal foil such as aluminum or an aluminum alloy, and may include a first uncoated electrode portion 111, which is an area where the first active material is not applied. The first uncoated electrode portion 111 may have a path for current flow between the first electrode plate and the outside. In addition, the first uncoated electrode portion 111 may be formed to overlap at the same position when the first electrode plate is wound to form a multi-tab structure. The first uncoated electrode portion 111 is formed to protrude from one side of the electrode assembly 110, and in some cases, a plurality of first uncoated electrode portions 111 may be welded together to form a first current collecting tab. The first uncoated electrode portions 111 may be aligned and protrude from one side of the electrode assembly 110. In some examples, the first uncoated electrode portion 111 may protrude from one side of the first electrode plate toward the lid assembly 160.

[0058] The second electrode plate is formed by applying a second electrode active material such as graphite or carbon to a second electrode current collector formed of a metal foil such as copper, a copper alloy, nickel, or a nickel alloy, and may include a second uncoated electrode portion 112, which is an area where the second electrode active material is not applied. The second uncoated electrode portion 112 may provide a path for current flow between the second electrode plate and the outside. In addition, the second uncoated electrode portion 112 may be formed to overlap at the same position when the second electrode plate 112 is wound to form a multi-tab structure. The second uncoated electrode portion 112 is formed to protrude from one side of the electrode assembly 110, and in some cases, a plurality of second uncoated electrode portions 112 may be welded together to form a second current collecting tab. In some examples, the second uncoated electrode portion 112 may protrude from one side of the second electrode plate toward the lid assembly 160.

[0059] In some examples, the first uncoated electrode portion 111 and the second uncoated electrode portion 112 may each protrude parallel to each other from the electrode assembly 110 toward the lid assembly 160. That is, in the electrode assembly 110, the first uncoated electrode portion 111 and the second uncoated electrode portion 112 may have different polarities and be spaced apart from each other. In addition, as described above, since the first electrode plate and the second electrode plate are formed by winding or overlapping, the first uncoated electrode portion 111 and the second uncoated electrode portion 112 that are repeatedly formed in each turn may be formed by overlapping a plurality of thin films. In this way, when a plurality of thin films are formed by overlapping, in order to facilitate current movement, the thin films may be connected by ultrasonic welding to be in contact with each other.

[0060] The separator can be located between the first electrode plate and the second electrode plate to prevent short circuits and allow lithium ions to move. The separator can be made of polyethylene, polypropylene, or a composite film of polyethylene and polypropylene. Meanwhile, the material of the separator does not limit the scope of the present invention. In some cases, the separator can be replaced with a solid electrolyte.

[0061] The electrode assembly 110 can be inserted into the housing 150 in a direction parallel to the winding axis. Additionally, the electrode assembly 110 can include a first electrode assembly 110a and a second electrode assembly 110b. Here, the first electrode assembly 110a and the second electrode assembly 110b can be electrically connected. Additionally, the first electrode assembly 110a and the second electrode assembly 110b can be fixed by separate fixing members 113 attached to some areas. The electrode assembly 110 can maintain its shape by means of the fixing members 113, and then can be connected to a current collector (not shown) in the correct position, and can even maintain the shape of the electrode assembly 110 within the final secondary battery structure. Additionally, in some examples, the spacers 120, 130 described later can be fixed to the electrode assembly 110 by the fixing members 113. Meanwhile, although Figure 2 two electrode assemblies 110 are shown, the present invention is not limited thereto, and multiple electrode assemblies (such as a third electrode assembly 110c and a fourth electrode assembly 110d, etc.) can be provided.

[0062] The electrode assembly 110 can be substantially accommodated in the housing 150 together with the electrolyte. The electrolyte can be composed of organic solvents (such as ethylene carbonate (EC), propylene carbonate (PC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), or dimethyl carbonate (DMC)) and lithium salts (such as LiPF6 or LiBF4). Additionally, the electrolyte can be in a liquid phase, a solid phase, or a gel phase.

[0063] The spacers 120, 130 contact one side of the electrode assembly 110 and one side of the housing 150 to be in the space between the electrode assembly 110 and the housing 150, and can minimize the void space, which is the empty space inside the housing 150. The spacers 120, 130 will be described in more detail later.

[0064] The housing 150 can be formed into a hollow rectangular parallelepiped having an opening at its top portion. Accordingly, the electrode assembly 110 can be inserted into the housing 150 through the opening. The housing 150 can include a bottom portion, a pair of long side portions, and a pair of short side portions connecting the pair of long side portions, and the opening can be provided opposite to the bottom portion. A cover plate 161 can be coupled to the opening of the housing 150 to seal the housing 150. The inner surface of the housing 150 is substantially insulated to prevent an internal electrical short circuit. Additionally, in some cases, one electrode of the electrode assembly 110 can be electrically connected to the housing 150 through the cover plate 161. Even in such a case, an internal electrical short circuit can be prevented by insulating the interior of the housing 150. In some examples, the housing 150 can be made of a conductive metal such as aluminum, an aluminum alloy, or nickel-plated steel, and can be manufactured by a deep drawing process or a bending and welding process.

[0065] The cover assembly 160 can be coupled to the top portion (opening) of the housing 150. Specifically, the cover assembly 160 can include a cover plate 161, an electrolyte injection port 162, a safety vent 163, a first terminal plate 1641, a second terminal plate 1642, a first insulating member 1651, and a second insulating member 1652.

[0066] The cover plate 161 seals the opening of the housing 150 and can be made of the same material as that of the housing 150. The cover plate 161 has a flat plate shape and can be made of a thin plate. For example, the cover plate 161 can be coupled to the housing 150 using laser welding. Additionally, the cover plate 161 can be electrically independent or, in some cases, can be electrically connected to a current collector plate.

[0067] Additionally, an electrolyte injection port 162 for injecting an electrolyte can be formed in the cover plate 161. The electrolyte is injected into the interior of the housing 150 through the electrolyte injection port 162, and the electrolyte injection port 62 can be sealed with a plug later.

[0068] Additionally, a safety vent 163 can be formed at a substantially central portion of the cover plate 161 and has a relatively small thickness compared to other regions. The safety vent 163 can prevent the secondary battery 100 according to an embodiment of the present disclosure from bursting and exploding when the pressure inside the housing 150 is higher than a set bursting pressure.

[0069] The first terminal plate 1641 and the second terminal plate 1642 can be electrically connected to the first electrode plate and the second electrode plate of the electrode assembly 110 through each current collector plate. That is, the first terminal plate 1641 can operate with a first polarity (e.g., as a positive electrode), and the second terminal plate 1642 can operate with a second polarity (e.g., as a negative electrode). Here, although not shown in the drawings, the current collector plate can be electrically connected to the first uncoated portion 111 of the first electrode and the second uncoated portion 112 of the second electrode. The current collector plate can be electrically connected to the first electrode plate and the second electrode plate by contacting the first uncoated portion 111 and the second uncoated portion 112 protruding from one end of the electrode assembly 110.

[0070] The first insulating member 1651 and the second insulating member 1652 can be formed between each of the first terminal plate 1641 and the second terminal plate 1642 and the cover plate 161. The first insulating member 1651 and the second insulating member 1652 are formed to surround the outer sides of each of the first terminal plate 1641 and the second terminal plate 1642 and can be made of an insulating material. In addition, each of the first insulating member 1651 and the second insulating member 1652 can seal the portion between the first terminal plate 1641 and the second terminal plate 1642. The first insulating member 1651 and the second insulating member 1652 can prevent external moisture from penetrating into the interior of the secondary battery 100 or prevent the electrolyte contained in the secondary battery 200 from leaking.

[0071] Figure 3 is a cross-sectional view taken along Figure 1 the line 3-3' of the secondary battery, Figure 4 is a cross-sectional view of a secondary battery including one electrode assembly according to an embodiment, Figure 5 is a cross-sectional view of a secondary battery including a plurality of electrode assemblies according to an embodiment, Figure 6 is a cross-sectional view of a secondary battery including an empty spacer according to an embodiment, Figure 7 is a perspective view showing a state in which a spacer of a secondary battery according to an embodiment is coupled to a case, and Figure 8 is a perspective view showing a state in which the spacer is coupled by a fixing member of a secondary battery according to an embodiment.

[0072] As described above, in the present disclosure, the wound-type electrode assembly 110 can be applied, and an ineffective space can be generated inside the housing 150 through the short-side bent portion 1102 of the electrode assembly 110. The electrolyte remaining in the ineffective space does not participate in the electrochemical reaction, resulting in low availability. Therefore, it is necessary to additionally inject the electrolyte into the void volume, which may require more electrolyte. In addition, due to the empty space inside the housing 150, deformation may occur in the electrode assembly 110 during collision or vibration. That is, due to the characteristics of the wound-type electrode assembly 110, there may be problems of difficulty in optimizing the electrolyte and reduced monomer safety due to the ineffective space caused by the short-side bent portion 1102.

[0073] Accordingly, referring to Figures 3 to 5 , in an embodiment of the present disclosure, the ineffective space can be minimized by inserting the spacers 120 and 130 into the empty space inside the housing 150, thereby reducing the amount of the remaining electrolyte that does not participate in the electrochemical reaction. In addition, the spacers 120 and 130 can be used as guides during the assembly of the monomer, thereby facilitating the assembly process. In addition, in the present disclosure, the empty space inside the housing 150 is filled with the spacers 120 and 130 to prevent the electrode assembly 110 from moving when an impact is applied to the battery monomer, thereby reducing physical impact and improving safety. The spacers 120 and 130 will now be described in more detail.

[0074] In some examples, the electrode assembly 110 may include a pair of long-side portions and a pair of short-side portions connecting the pair of long-side portions. In addition, the electrode assembly 110 may have a flat portion 1101 and a bent portion 1102. The pair of long-side portions may have the flat portion 1101, and the pair of short-side portions may have the bent portion 1102. An empty space is formed between the bent portion 1102 and the housing 150 through the bent portion 1102, and this empty space may be referred to as the first region (A). The first region (A) may have four regions formed at the corners between the electrode assembly 110 and the housing 150, regardless of the number of the electrode assemblies 110. These four first regions (A) may be formed in slightly different shapes according to the winding type of the electrode assembly 110, but the following description will be given under the assumption that the first regions (A) have the same shape.

[0075] The first region (A) may have a bent portion formed by the bent portion 1102 of the electrode assembly 110 and a corner portion formed by the edge of the housing 150. That is, the shape of the first region (A) may be formed according to the shape of the bent portion 1102 of the electrode assembly 110 and the shape of the edge portion of the housing 150.

[0076] In some examples, the first spacer 120 may be interposed in the first region (A). That is, the first spacer 120 may be formed in a shape corresponding to the shape of the first region (A) and may be interposed at the four corners, respectively. Similar to the first region (A), the first spacer 120 may be formed in a slightly different shape, but the following description will be given under the assumption that the first spacer 20 has the same shape. The first spacer 120 is interposed in the first region (A) so that no empty space is generated in the first region (A), and thus may be formed in a shape corresponding to the shape of the first region (A). Each of the first spacers 120 may include a first surface 121 in contact with the electrode assembly 110 and two second surfaces 122 in contact with the edge portion of the housing 150. The first surface 121 corresponds to the curved portion of the first region (A), and the second surface 122 corresponds to the edge portion of the first region (A). That is, the first surface 121 of the first spacer 120 may be formed as a curved surface corresponding to the curved portion 1102 of the electrode assembly 110. In addition, since the second surface 122 of the first spacer 120 is in contact with the edge portion of the housing 150, it may be formed to correspond to the edge shape of the housing 150. For example, when the edge is at a right angle, the two second surfaces 122 of the first spacer 120 may be connected at a right angle. That is, the first spacer 120 may have the shape of a triangular prism with the first surface 121 formed as a concave curved surface. However, when the edge is formed with a gentle curved surface, the two surfaces of the second surface 122 of the first spacer 120 may be connected with a gentle curved surface.

[0077] Meanwhile, in some examples, when the electrode assembly 110 is composed of a plurality of electrode assemblies, an empty space may be formed between adjacent electrode assemblies 110a to 110d through the curved portion 1102 of each electrode assembly 110. The empty space may be referred to as the second region (B). For example, when the electrode assembly 110 is composed of two electrode assemblies, the second region (B) may have two regions, each formed on both sides of the electrode assemblies 110a, 110b. In addition, when the electrode assembly 110 is composed of four electrode assemblies, the second region (B) may have six regions, with every three regions formed on both sides of the electrode assemblies 110a, 110b. Depending on the winding type of the electrode assembly 110, the plurality of second regions (B) may be formed in different shapes, but the following description will be given under the assumption that the second region (B) has the same shape. Depending on the winding type of the electrode assembly 110, the plurality of second regions (B) may be formed in different shapes, but the following description will be given under the assumption that the second region (B) has the same shape.

[0078] The second region (B) may have a bent portion formed by the bent portions 1102a, 1102b of the electrode assemblies 110a, 110b and a straight portion formed by the housing 150. That is, the second region (B) may be shaped according to the shapes of the bent portions 1102a, 1102b of the electrode assemblies 110a, 110b. Additionally, when the shape of the inner surface of the housing 150 is not a uniform surface and forms a pattern, the shape of the straight portion of the second region (B) may be formed according to the pattern.

[0079] In some examples, the second spacer 130 may be interposed in the second region (B). That is, the second spacer 130 may be formed in a shape corresponding to the shape of the second region (B) and may be respectively interposed between adjacent electrode assemblies 110a, 110b. Similar to the second region (B), all of the second spacers 130 may be formed in slightly different shapes, but the following description will be given under the assumption that the second spacers 130 have the same shape. The second spacer 130 is interposed in the second region (B) so that no empty space is generated in the second region (B), and thus may be formed in a shape corresponding to the shape of the second region (B). Each of the second spacers 130 may include two first surfaces 131 that contact the electrode assembly 110 and a second surface 132 that contacts the inner surface of the housing 150. The two first surfaces 131 correspond to the bent portion of the second region (B), and the second surface 132 corresponds to the straight portion of the second region (B). That is, the first surface 131 of the second spacer 130 may be formed as a curved surface corresponding to the bent portions 1102a, 1102b of the electrode assemblies 110a, 110b. Additionally, since the second surface 132 of the second spacer 130 contacts the inner surface of the housing 150, it may be formed as a straight line. For example, the second spacer 130 may have the shape of a triangular prism with two first surfaces 131 formed as concave curved surfaces.

[0080] The first spacer 120 and the second spacer 130 may be formed as a pair on both sides where the first electrode uncoated portion 111 and the second electrode uncoated portion 112 of the electrode assembly 110 do not protrude. In some examples, the same first spacer 120 and the same second spacer 130 may be respectively disposed on the left and right sides of the electrode assembly 110. Accordingly, in one embodiment of the present disclosure, the first spacer 120 and the second spacer 130 are interposed in the empty space within the housing 150, thereby eliminating the ineffective space.

[0081] In some examples, the first spacer 120 and the second spacer 130 may be separated from each other. That is, the first spacer 120 and the second spacer 130 may be formed as a separated structure, but are not limited thereto. Alternatively, the first spacer 120 and the second spacer 130 may be integrally formed. For example, the first spacer 120 and the second spacer 130 may be integrally manufactured or combined.

[0082] In addition, referring to Figure 6 , at least one of the first spacer 120 and the second spacer 130 may be formed to have an empty internal space. In some examples, all of the first spacer 120 and the second spacer 130 may be formed to have an empty internal space, or some of the first spacer 20 and the second spacer 130 may be formed to have an empty internal space. Accordingly, in one embodiment of the present disclosure, the weight of the secondary battery 100 may be reduced.

[0083] Meanwhile, referring to Figure 7 , at least one of the first spacer 120 and the second spacer 130 may be coupled to the inside of the case 150. For example, the first spacer 120 and the second spacer 130 may be pre-designed to fit the cell design (thickness of the electrode assembly, number of electrode assemblies, etc.) and the shape of the case 150, so that the first spacer 120 and the second spacer 130 may be pre-attached to the case 150 before inserting the electrode assembly 110 into the case 150.

[0084] In addition, referring to Figure 8 , in some examples, at least one of the first spacer 120 and the second spacer 130 may be coupled to the plurality of electrode assemblies 110 by a fixing member 113. For example, after assembling the electrode assembly 110 and the cover assembly 160, the first spacer 120 and the second spacer 130 may be fixed to the electrode assembly 110 by pasting and fixing the fixing member 113 with tape, thereby attaching the first spacer 120 and the second spacer 130 to the electrode assembly 110 before inserting them into the case 150.

[0085] These first spacers 120 and second spacers 130 may be made of an insulating material and may be made of a material that does not undergo an electrochemical reaction inside the monomer. For example, the first spacers 120 and second spacers 130 may be formed of one or a mixture of two or more selected from polypropylene (PP), polymethylpentene (PMP), polyethylene terephthalate (PET), polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyetherimide (PEI), polyamideimide, polysulfone (PES), polyphenylene ether, polyphenylene sulfide, and polyethylene naphthalene. In some examples, the first spacers 120 and second spacers 130 may be made of the same material, but are not limited thereto. Instead, the first spacers 120 and second spacers 130 may be made of different materials.

[0086] What is described above is only one example for implementing the exemplary secondary battery according to the present disclosure, and the present disclosure is not limited to the embodiments described above. As claimed in the patent claims, the technical spirit of the present disclosure lies in the extent to which those skilled in the art can make various modifications without departing from the gist of the present disclosure. That is, although the present disclosure has been described with limited examples and drawings, the present disclosure is not limited thereto, and those skilled in the art to which the present disclosure pertains can make various modifications and variations within the equivalent scope between the technical concept of the present disclosure and the scope of the claims.

Claims

1. A secondary battery comprising: Electrode assembly; a housing accommodating the electrode assembly and having at least one opening; a cover assembly coupled through the opening to seal the housing; as well as at least one first spacer in contact with one side of the electrode assembly and one side of the case to be interposed in a space between the electrode assembly and the case, The first spacer is formed into a shape corresponding to a shape of the space between the electrode assembly and the case.

2. The secondary battery according to claim 1, wherein the electrode assembly comprises a first electrode and a second electrode, the first electrode and the second electrode each comprising an electrode plate and an electrode uncoated portion, and the electrode uncoated portion of the first electrode and the electrode uncoated portion of the second electrode protrude in at least one of a direction toward the cap assembly and a direction opposite to the cap assembly. 3 . The secondary battery according to claim 2 , wherein the first separator is formed as a pair at both sides of the electrode assembly, and the electrode uncoated portion of the first electrode and the electrode uncoated portion of the second electrode do not protrude at the both sides of the electrode assembly. The secondary battery according to claim 3 , wherein the electrode assembly is formed of a plurality of electrode assemblies. 5 . The secondary battery according to claim 4 , further comprising at least one second spacer contacting one surface of the plurality of electrode assemblies and interposed in a space between the plurality of electrode assemblies. 6 . The secondary battery according to claim 5 , wherein the second spacer is formed in a shape corresponding to a shape of the space between the plurality of electrode assemblies.

7. The secondary battery according to claim 5, wherein the second separator is formed as a pair at both sides of each of the plurality of electrode assemblies, and the electrode uncoated portion of the first electrode and the electrode uncoated portion of the second electrode do not protrude at the both sides of each of the plurality of electrode assemblies. 8 . The secondary battery according to claim 4 , wherein in the plurality of electrode assemblies, the electrode uncoated portion of the first electrode and the electrode uncoated portion of the second electrode protrude in the same direction. 9 . The secondary battery according to claim 5 , wherein the first separator and the second separator are formed to be separated from each other. 10 . The secondary battery according to claim 5 , wherein the first separator and the second separator are integrally formed. 11 . The secondary battery according to claim 5 , wherein at least one of the first spacer and the second spacer is formed as an empty inner space. 12 . The secondary battery according to claim 5 , wherein at least one of the first spacer and the second spacer is coupled to an interior of the case. 13 . The secondary battery according to claim 5 , further comprising a fixing member surrounding sides of the plurality of electrode assemblies positioned in series. 14 . The secondary battery according to claim 13 , wherein at least one of the first spacer and the second spacer is coupled to the plurality of electrode assemblies by the fixing member. 15 . The secondary battery according to claim 5 , wherein the first spacer and the second spacer are made of an insulating material. 16 . The secondary battery of claim 2 , wherein the electrode uncoated portion of the first electrode and the electrode uncoated portion of the second electrode are spaced apart from each other and protrude from the electrode plate toward the cap assembly. 17 . The secondary battery according to claim 1 , wherein the electrode assembly is wound in a winding type.

Images