Secondary battery

Abstract

An embodiment of the present invention provides a secondary battery, wherein, by charging a housing with positive charge by a high-resistance positive electrode charging member, an alloy (e.g., a lithium aluminum (LiAl) alloy) is not formed on the inner surface of the housing by an electrolyte (i.e., the housing is not corroded), and when a negative electrode terminal is short-circuited with a positive electrode housing, a short-circuit current is limited. As an example, a secondary battery according to an embodiment of the present invention includes: an electrode assembly; a housing in which the electrode assembly is accommodated; a cap plate coupled to the housing and sealing the electrode assembly; a terminal connected to the electrode assembly and exposed through the cap plate; and a charging member interposed between the cap plate and the terminal, wherein the charging member may include a conductive member interposed between the cap plate and the terminal and an insulating member interposed between the conductive member, the cap plate, and the terminal.

Description

Technical Field

[0001] One embodiment of the present invention relates to a secondary battery. Background Art

[0002] A secondary battery is a power storage system that provides excellent energy density for storing electrical energy in the form of chemical energy. Compared to non-rechargeable primary batteries, secondary batteries are rechargeable and are widely used in IT equipment such as smartphones, mobile phones, laptops, and tablet personal computers. Recently, in order to prevent environmental pollution, people's interest in electric vehicles has increased, and accordingly high-capacity secondary batteries are being used in electric vehicles. Such secondary batteries need to have characteristics such as high density, high output, and stability.

[0003] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not constitute prior art. Summary of the invention

[0004] Technical issues

[0005] One embodiment of the present invention provides a secondary battery in which, by charging a shell with positive electricity by a high-resistance positive electrode charging member, an alloy (e.g., a lithium aluminum (LiAl) alloy) is not formed on the inner surface of the shell by an electrolyte (i.e., the shell is not corroded), and when a negative electrode terminal is short-circuited with a positive electrode shell, the short-circuit current is limited.

[0006] Furthermore, an embodiment of the present invention provides a secondary battery in which the positive electrode charging member is not deformed or damaged by an external welding heat source (ie, has improved durability) by forming the positive electrode charging member by a two-color injection molding method.

[0007] In addition, an embodiment of the present invention provides a secondary battery, in which, since the positive electrode charging component has protrusions and recesses, external foreign matter does not flow into the interior of the shell, and internal foreign matter of the shell does not flow out to the outside, thereby improving the coupling force between the positive electrode charging component and the shell.

[0008] Solution to the problem

[0009] A secondary battery according to an embodiment of the present invention may include: an electrode assembly; a shell in which the electrode assembly is accommodated; a cover plate coupled to the shell and sealing the electrode assembly; a terminal connected to the electrode assembly and exposed through the cover plate; and a charging member between the cover plate and the terminal, wherein the charging member may include a conductive member between the cover plate and the terminal and an insulating member between the conductive member, the cover plate and the terminal.

[0010] The conductive member may include a polymer and a conductive filler, the polymer including polyphenylene sulfide (PPS), polyacetylene (PA), polyparaphenylene vinylene (PPV), polypyrrole (PPY), polyaniline (PANI), polythiophene (PT) or poly-3,4-polyethylenedioxythiophene (PEDOT), and the conductive filler may include carbon black, carbon fiber or carbon nanotube.

[0011] The resistance of the conductive member may be 1 kΩ to 1000 MΩ.

[0012] The insulating member may include a polymer including polycarbonate (PC), polyphenylene sulfide (PPS), polysulfone (PSF), polyethersulfone (PES), polyamideimide (PAI), or polyimide (PI).

[0013] The heat-resistant temperature of the insulating member may be 120°C to 300°C.

[0014] The terminal may include a terminal post electrically connected to the electrode assembly and penetrating the cap plate, and a terminal plate coupled to the terminal post and located on the cap plate, and the conductive member may contact the cap plate, the terminal post, and the terminal plate.

[0015] The insulating member may contact the conductive member, the cap plate, and the terminal plate.

[0016] The secondary battery may further include a sealing gasket interposed between the terminal column and the cap plate, wherein the conductive member contacts the sealing gasket.

[0017] The cap plate may include a first recess, and the conductive member may include a first protrusion coupled to the first recess.

[0018] The cap plate may include a second recess, the conductive member may include a second protrusion coupled to the second recess, and the insulating member may include a first protrusion coupled to the second recess.

[0019] The cap plate may include a first protrusion, and the conductive member may include a first recess coupled to the first protrusion.

[0020] The conductive member may include a second recess, and the insulating member may include a second protrusion coupled to the second recess.

[0021] Advantageous Effects of the Present Disclosure

[0022] One embodiment of the present invention can provide a secondary battery in which, by charging the shell with positive electricity by a high-resistance positive electrode charging member, an alloy (e.g., lithium aluminum (LiAl) alloy) is not formed on the inner surface of the shell by an electrolyte (i.e., the shell is not corroded), and when the negative electrode terminal is short-circuited with the positive electrode shell, the short-circuit current is limited.

[0023] Furthermore, an embodiment of the present invention can provide a secondary battery in which a positive electrode charging member is formed by a two-color injection molding method, and the positive electrode charging member is not deformed or damaged by an external welding heat source (ie, has improved durability).

[0024] In addition, an embodiment of the present invention can provide a secondary battery, in which, since the positive electrode charging component has protrusions and recesses, external foreign matter does not flow into the interior of the shell, and internal foreign matter of the shell does not flow out to the outside, thereby improving the coupling force between the positive electrode charging component and the shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a perspective view of an exemplary secondary battery according to an embodiment of the present invention.

[0026] Figure 2a and Figure 2b It is shown Figure 1 A cross-sectional view of an example secondary battery is shown.

[0027] Figure 3a and Figure 3b are a perspective view and a cross-sectional view showing an example positive terminal and an example positive electrode charging member in an example secondary battery according to an embodiment of the present invention.

[0028] Figure 4a , Figure 4b and Figure 4c are a top perspective view, a top plan view, and a bottom plan view showing an example positive electrode charging member in an example secondary battery according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0030] Examples of the present invention are provided to more completely explain the present invention to those skilled in the art, and the following examples may be modified in various other forms. However, the present invention may be embodied in many different forms and should not be construed as being limited to the example embodiments set forth herein. Instead, these example embodiments are provided so that this disclosure will be exhaustive and complete and to convey aspects and features of the present invention to those skilled in the art.

[0031] In addition, in the accompanying drawings, the size or thickness of various components is exaggerated for simplicity and clarity. The same reference numerals always refer to the same elements. As used herein, the term "and / or" includes any combination and all combinations of one or more of the associated listed items. In addition, it will be understood that when element A is referred to as being "connected to" element B, element A can be directly connected to element B, or an intermediate element C can exist between them so that element A and element B are indirectly connected to each other.

[0032] The terms used herein are only used for the purpose of describing specific embodiments and are not intended to limit the present disclosure. As used herein, the singular form is also intended to include the plural form, unless the context clearly indicates otherwise. It will be further understood that the terms "comprise" and / or "comprising" when used in this specification clearly indicate the presence of stated features, numbers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, numbers, steps, operations, elements, parts and / or their groups.

[0033] It will be understood that, although the terms first, second, etc. may be used herein to describe various members, elements, regions, layers, and / or parts, these members, elements, regions, layers, and / or parts should not be limited by these terms. These terms are only used to distinguish one member, element, region, layer, and / or part from another member, element, region, layer, and / or part. Therefore, for example, the first member, first element, first region, first layer, and / or first part discussed below may be referred to as the second member, second element, second region, second layer, and / or second part without departing from the teachings of the present invention.

[0034] Figure 1 1 is a perspective view of a secondary battery 100 or 200 according to an embodiment of the present invention. Figure 1 In the example shown, the secondary batteries 100 and 200 include electrode assemblies 110 and 210, respectively (see Figure 2a and 2b ), a first terminal 120 , a second terminal 130 , a can 140 , and a cap assembly 150 .

[0035] In some examples, the first terminal 120 may be

[0036] The first terminal 120 may be formed through the cap assembly 150 and exposed upward. In some examples, the first terminal 120 may include or be referred to as a negative terminal, and the second terminal 130 may include or be referred to as a positive terminal.

[0037] The upper insulating member 163 may be interposed between the first terminal 120 and the cap assembly 150, and the charging member 180 may be interposed between the second terminal 130 and the cap assembly 150. Accordingly, the first terminal 120 and the cap assembly 150 may be electrically insulated (ie, separated) from each other. In addition, the second terminal 130 and the cap assembly 150 may be electrically connected (ie, connected) to each other, and accordingly, the tank 140 may be charged with, for example, positive polarity (or negative polarity).

[0038] In some examples, the can 140 may be formed by using a metal plate through a deep drawing process or using a metal plate through a bending and welding process, and may be in the form of a hexahedron having a space in which the electrode assemblies 110 and 120 are accommodated and the cap assembly 150 may be placed. In some examples, the can 140 may include a rectangular bottom 141 having long sides and short sides, long sides 142 and 143 bent and extended from each long side of the bottom 141 toward the cap assembly 150, and short sides 144 and 145 extending from each short side of the bottom 141 toward the cap assembly 150. In some examples, the can 140 may include or be referred to as a shell, a housing, or an outer material.

[0039] In some examples, the cover assembly 150 may include a cover plate 151 , a plug 152 , and a safety vent 153 , which will be described again below.

[0040] Figure 2a and Figure 2b yes Figure 1 The example secondary batteries 100 and 200 are shown in cross-sectional view. Figure 2a In the illustrated example, the secondary battery 100 may include an electrode assembly 110 having a winding axis in a horizontal direction (ie, a direction approximately parallel to a longitudinal direction of the cap assembly 150), Figure 2b In the example shown, the secondary battery 200 may include an electrode assembly 210 having a winding axis in a vertical direction, ie, a direction approximately perpendicular to the longitudinal direction of the cap assembly 150. In some examples, the electrode assembly may include a stacked type and a wound type.

[0041] Will describe Figure 2aThe secondary battery 100 shown in . The electrode assembly 110 can be formed by winding or overlapping a stack of a first electrode plate 111, a separator 113, and a second electrode plate 112 formed in the shape of a thin plate or film. In some examples, the first electrode plate 111 can be used as a negative electrode and the second electrode plate 112 can be used as a positive electrode. Of course, the reverse is also possible. In some examples, the first electrode plate 111 is formed by coating a first electrode active material (e.g., graphite or carbon) on a first electrode current collector formed of a metal foil (e.g., copper, copper alloy, nickel, or nickel alloy), and may include a first electrode uncoated portion 111a to which the first electrode active material is not coated. In some examples, the second electrode plate 112 is formed by coating a second electrode active material (e.g., a transition metal oxide) on a second electrode current collector formed of a metal foil (e.g., aluminum or an aluminum alloy), and may include a second electrode uncoated portion 112a to which the second electrode active material is not coated. In some examples, the separator 113 is located between the first electrode plate 111 and the second electrode plate 112 to prevent short circuits and enable lithium ions to move, and may include polyethylene, polypropylene, or a composite film of polyethylene and polypropylene. In addition, the separator 113 may include a functional film coated with an inorganic material layer on a porous polymer film. Moreover, the separator 113 may be replaced with an inorganic solid electrolyte that does not require a liquid or gel electrolyte, such as a sulfide, oxide, or phosphate compound electrolyte. As described above, the first terminal 120 and the second terminal 130, which are electrically connected to the first electrode plate 111 and the second electrode plate 112, respectively, may be located at both ends of the electrode assembly 110. In some examples, the electrode assembly 110 may be housed in a tank 140 together with an electrolyte. In some examples, the electrolyte may include a lithium salt, such as LiPF in an organic solvent such as EC (ethylene carbonate), DMC (dimethyl carbonate), DEC (diethyl carbonate), or EMC (ethyl methyl carbonate). 6 In addition, the electrolyte may be in liquid or gel form. In some examples, the electrolyte may be omitted when an inorganic solid electrolyte is used.

[0042] The first terminal 120 is formed of metal and may be electrically connected to the first electrode plate 111. In some examples, the first terminal 120 may include a first current collecting plate 121, a first terminal column 122, and a first terminal plate 123. In some examples, the first current collecting plate 121 may be in contact with the first electrode uncoated portion 111a protruding from one end of the electrode assembly 110. In fact, the first current collecting plate 121 may be welded to the first electrode uncoated portion 111a. In some examples, the first current collecting plate 121 is formed in a substantially "┎" shape and may have a terminal hole 121a formed in an upper portion thereof. In some examples, the first terminal column 122 may be inserted into the terminal hole 121a to be riveted and / or welded. In some examples, the first current collecting plate 121 may be made of copper or a copper alloy. In some examples, the first terminal column 122 protrudes through the cap plate 151 described later and extends upward by a predetermined length, and may be electrically connected to the first current collecting plate 121 from the lower portion of the cap plate 151. In addition, in some examples, the first terminal column 122 may protrude toward the upper portion of the cover plate 151 and extend a predetermined length, and at the same time, may also include a flange 122a that prevents the first terminal column 122 from falling off from the lower portion of the cover plate 151. The area below the flange 122a in the first terminal column 122 may be inserted into the first terminal hole 121a of the first current collecting plate 121 and then riveted and / or welded. In some examples, the first terminal column 122 may be electrically insulated from the cover plate 151. In some examples, the first terminal column 122 may be made of copper, copper alloy, aluminum, or aluminum alloy. The first terminal plate 123 may include a hole 123a, and the first terminal column 122 may be coupled to the hole 123a and riveted and / or welded to the hole 123a. In some examples, the boundaries of the first terminal column 122 and the first terminal plate 123 exposed upward may be welded to each other. For example, a laser beam may be provided to the boundary region of the first terminal column 122 and the first terminal plate 123, thereby connecting the boundary region after welding each other and then cooling. In some examples, a bus bar (not shown) made of aluminum or an aluminum alloy is welded to the first terminal plate 123, so that a plurality of secondary batteries can be connected in series or in parallel.

[0043] The second terminal 130 is also formed of metal and can be electrically connected to the second electrode plate 112. In some examples, the second terminal 130 may include a second current collecting plate 131, a second terminal column 132, and a second terminal plate 133. The second current collecting plate 131 may be in contact with the second electrode uncoated portion 112a protruding from one end of the electrode assembly 110. In some examples, the second current collecting plate 131 is formed in a substantially "┑" shape and may have a terminal hole 131a formed in an upper portion thereof. In some examples, the second terminal column 132 may be inserted into the terminal hole 131a to be riveted and / or welded. The second current collecting plate 131 may be made of, for example, but not limited to, aluminum or an aluminum alloy. The second terminal column 132 may protrude through the cap plate 151 described later and extend upward by a predetermined length, and may be electrically connected to the second current collecting plate 131 from the lower portion of the cap plate 151. The second terminal column 132 may protrude toward the upper portion of the cap plate 151 and extend a predetermined length, and at the same time, may also include a flange 132a that prevents the second terminal column 132 from falling off from the lower portion of the cap plate 151. The area below the flange 132a in the second terminal column 132 may be inserted into the second terminal hole 131a of the second current collecting plate 131, and then riveted and / or welded. In some examples, the second terminal column 132 may be made of aluminum or an aluminum alloy. The second terminal plate 133 may include a hole 133a, and the second terminal column 132 may be coupled to the hole 133a. In addition, the second terminal column 132 and the second terminal plate 133 may be riveted or welded to each other. In some examples, the boundaries of the second terminal column 132 and the second terminal plate 133 exposed upward may be welded to each other. For example, a laser beam may be provided to the boundary area of ​​the second terminal column 132 and the second terminal plate 133, so that the boundary area is coupled after being welded to each other, and then cooled. In addition, a bus bar (not shown) made of aluminum or an aluminum alloy is welded to the second terminal plate 133, so that a plurality of secondary batteries can be connected in series or in parallel. In some examples, the second terminal plate 133 can be electrically connected to the cap plate 151, so that the cap plate 151 and the tank 140 to be described below can have the same polarity (e.g., positive polarity) as the second terminal 130.

[0044] The cap assembly 150 may be coupled to the tank 140. In some examples, the cap assembly 150 may include or be referred to as a cap plate 151. The cap plate 151 seals the space of the tank 140 and may be formed of the same material as the tank 140. In some examples, the cap plate 151 may be coupled to the tank 140 by laser welding. In some examples, the cap plate 151 may have the same polarity as the second terminal 130 as described above, so the cap plate 151 and the tank 140 may have the same polarity. In some examples, the cap plate 151 may include a first through hole 151a through which the first terminal column 122 passes and a second through hole 151b through which the second terminal column 132 passes. In some examples, the cap plate 151 may further include an injection hole 151c and a vent hole 151d, the electrolyte is injected into the injection hole 151c, and the safety vent is installed in the vent hole 151d. In some examples, the plug 152 may block the injection hole 151c to prevent leakage of the electrolyte contained in the tank 140. In some examples, the plug 152 may be laser welded to the cap plate 151 after being coupled to the injection hole 151c. In some examples, the safety vent 153 blocks the vent hole 151d, and when the internal pressure of the tank 140 becomes higher than the set pressure, the high-pressure gas inside may be discharged to the outside. In some examples, the safety vent 153 may be laser welded to the cap plate 151 after being coupled to the vent hole 151d.

[0045] In some examples, the insulating sealing gasket 161 may be interposed between the first terminal column 122 and the first through hole 151a of the cap plate 151. In some examples, the lower insulating member 162 may be interposed between the first current collecting plate 121 and the cap plate 151. In some examples, the upper insulating member 163 may be interposed between the first terminal plate 123 and the cap plate 151. Accordingly, the first terminal 120 may be electrically insulated (separated) from the cap plate 151.

[0046] In some examples, the insulating sealing gasket 171 may be interposed between the second terminal column 132 and the second through hole 151b of the cap plate 151. In some examples, the lower insulating member 172 may be interposed between the second current collecting plate 131 and the cap plate 151. In some examples, the charging member 180 may be interposed between the second terminal plate 133 and the cap plate 151. Accordingly, the second terminal 130 may be electrically connected to the cap plate 151.

[0047] We will now describe Figure 2b. The secondary battery 200 shown in FIG. The secondary battery 200 has a different structure from the secondary battery 100 of the above-described embodiment in terms of the electrode assembly 220 and the connection relationship between the electrode assembly 220 and the terminals 120 and 130. The first electrode tab 211a may be interposed between the electrode assembly 210 and the first terminal 120, and the second electrode tab 212a may be interposed between the electrode assembly 210 and the second terminal 130. That is, the first electrode tab 211a may extend from the upper end of the electrode assembly 210 toward the lower end of the first terminal column 122 to be electrically connected or welded to the first terminal column 122. Similarly, the second electrode tab 212a may extend from the upper end of the electrode assembly 210 toward the lower end of the second terminal column 132 to be electrically connected or welded to the second terminal column 132. In fact, the first electrode tab 211a may be the first uncoated portion itself in the first electrode plate 211 of the electrode assembly 210 that is not coated with the first active material, or may be a separate member connected to the first uncoated portion. Here, the material of the first non-coating portion is the same as that of the first electrode plate, and the material of the separate member may be selected from one of nickel, nickel alloy, copper, copper alloy, aluminum, aluminum alloy, and their equivalents. In addition, in practice, the second electrode tab 212a may be the second non-coating portion itself in the second electrode plate 212 of the electrode assembly 210 to which the second active material is not applied, or may be a separate member connected to the second non-coating portion.

[0048] Figure 3a and Figure 3b 1 is a perspective view and a cross-sectional view showing an example positive terminal 130 and an example positive electrode charging member 180 in an example secondary battery 100 according to an embodiment of the present invention. This structure can be applied to the example secondary battery 200 in the same or similar manner.

[0049] like Figure 3a and Figure 3b As shown, the positive electrode charging member 180 may be interposed between the cap plate 151 and the positive terminal 130. In some examples, the charging member 180 may include a conductive member 181 and an insulating member 183 interposed between the cap plate 151 and the positive terminal 130. In some examples, the conductive member 181 may include a polymer and a conductive filler.

[0050] In some examples, the polymer may include polyphenylene sulfide (PPS), polyacetylene (PA), polyparaphenylene vinylene (PPV), polypyrrole (PPY), polyaniline (PANI), polythiophene (PT), or poly-3,4-polyethylenedioxythiophene (PEDOT). In some examples, the conductive filler may include carbon black, carbon fiber, or carbon nanotubes. In some examples, the resistance of the conductive member 181 may be about 1 kΩ to about 1000 MΩ. In some examples, when the polymer itself is conductive, the conductive filler may be omitted. In some examples, when the conductive filler is dispersed in the polymer, the conductive member 181 may be black.

[0051] In some examples, the insulating member 183 may include a polymer, wherein the polymer may include polycarbonate (PC), polyphenylene sulfide (PPS), polysulfone (PSF), polyethersulfone (PES), polyamideimide (PAI) or polyimide (PI). In some examples, the heat-resistant temperature of the insulating member 183 may be about 120° C. to about 300° C., which is higher than the heat-resistant temperature of the conductive member 181.

[0052] In some examples, first, the conductive member 181 may be formed by injection molding, and then, the insulating member 183 may be formed by injection molding while surrounding the conductive member 181. In some examples, the charging member 180 may be formed by a two-color injection molding process.

[0053] In this way, since the positive terminal 130 and the cap plate 151 are electrically connected through the positive electrode charging member 180, the cap plate 151 and the can 140 can be positively charged. Therefore, an alloy (e.g., a lithium aluminum (LiAl) alloy) is not formed on the inner surface of the can 140 by the electrolyte containing lithium ions, and thus corrosion on the inner surface of the can 140 can be prevented. In addition, since the positive electrode charging member 180 has a relatively high resistance, even if the negative terminal 120 is short-circuited with the can 140 of the positive electrode, the positive electrode charging member 180 mainly consumes the short-circuit current. In some examples, when the negative terminal 120 is short-circuited with the can 140 of the positive electrode, the positive electrode charging member 180 mainly consumes the energy of the battery 100, thereby preventing the battery 100 from being ignited.

[0054] In addition, since the insulating member 183 having a relatively high heat-resistant temperature wraps the conductive member 181, the conductive member 181 is not deformed or damaged by an external welding heat source. In other words, after the plug 152 is coupled to the injection hole 151c of the cap plate 151, the plug 152 can be welded to the cap plate 151, and the insulating member 183 can block the heat generated at this time so that the heat is not transferred to the conductive member 181. Accordingly, the positive electrode charging member 180 is not damaged or deformed by the heat generated during the welding of the plug 152 located between the safety vent 153 and the positive terminal 130.

[0055] In some examples, the conductive member 181 may contact the cap plate 151, the terminal column 132, and the terminal plate 133. In some examples, the conductive member 181 may contact the flange 132a. In some examples, the conductive member 181 may further contact the sealing gasket 171. In some examples, the insulating member 183 may contact the cap plate 151, the conductive member 181, and the terminal plate 133.

[0056] In some examples, the cap plate 151 may further include a first recess 154 a formed on the upper surface, and the conductive member 181 may further include a first protrusion 181 a coupled to the first recess 154 a .

[0057] In some examples, the cover plate 151 may further include a second recess 154b formed on the upper surface as an outer side of the first recess 154a, the conductive member 181 may further include a second protrusion 181b coupled to the second recess 154b, and the insulating member 183 may further include a first protrusion 183a coupled to the second recess 154b. In some examples, in a state where the second protrusion 181b of the conductive member 181 and the first protrusion 183a of the insulating member 183 contact each other, the second protrusion 181b and the first protrusion 183a may be simultaneously coupled to the second recess 154b of the cover plate 151.

[0058] In some examples, the cap plate 151 may further include a first protrusion 155a formed between the first recess 154a and the second recess 154b, and the conductive member 181 may further include a first recess 181c coupled to the first protrusion 155a of the cap plate 151. In some examples, the conductive member 181 may further include a second recess 181d formed on the upper surface, and the insulating member 183 may further include a second protrusion 183b coupled to the second recess 181d. In some examples, the insulating member 183 may further include a third protrusion 183c formed on the upper surface, and the third protrusion 183c may contact the outer surface of the terminal plate 133.

[0059] In this way, the first and second recesses 154a and 154b and the first protrusion 155a are provided to the cap plate 151, the first and second protrusions 181a and 181b and the first recess 181c are provided to the conductive member 181, and the first protrusion 183a is provided to the insulating member 183, so that the moving path of foreign matter is lengthened, thereby preventing foreign matter from flowing into the interior of the tank 140 and preventing foreign matter from flowing out of the interior of the tank 140. In addition, the second recess 181d is provided on the upper surface of the conductive member 181, and the second protrusion 183b is provided on the lower surface of the insulating member 183, and then coupled to each other, thereby improving the coupling force between the conductive member 181 and the insulating member 183.

[0060] In some examples, the cap plate 151 may further include a second protrusion 155b formed on the lower surface, and the lower insulating member 172 may further include a recess 172a formed on the upper surface. In addition, since the recess 172a of the lower insulating member 172 is coupled to the second protrusion 155b of the cap plate 151, the coupling force between the cap plate 151 and the lower insulating member 172 can be improved.

[0061] Figure 4a , Figure 4b and Figure 4c 1 and 2 are top perspective views, top plan views, and bottom plan views showing an example positive electrode charging member 180 in an example secondary battery 100 according to an embodiment of the present invention. The positive electrode charging member 180 may also be applied to the above-described secondary battery 200 in the same or similar manner.

[0062] like Figure 4a , Figure 4b and Figure 4c As shown, the positive electrode charging member 180 may further include a through hole 182 formed at the center of the conductive member 181. The terminal column 132 may pass through the through hole 182 of the conductive member 181 and may contact an inner surface of the through hole 182.

[0063] In some examples, the insulating member 183 may further include a fourth protrusion 183d formed on the opposite side. The fourth protrusion 183d may be shaped to protrude inward from the third protrusion 183c (i.e., a square circumference) of the insulating member 183. The fourth protrusion 183d of the insulating member 183 is coupled to a recess (not shown) formed on the lower surface of the terminal plate 133 to prevent the terminal plate 133 and the insulating member 183 from rotating relative to each other. In some examples, the first recess 181c formed in the conductive member 181 may have a substantially rectangular line shape. The first protrusion 181a may be formed on the inner side of the first recess 181c, and the second protrusion 181b may be formed on the outer side of the first recess 181c.

[0064] In some examples, the first protrusion 183a of the insulating member 183 may have a substantially rectangular line shape by wrapping the outside of the second protrusion 181b of the conductive member 181. The positive electrode charging member 180 having such a structure is coupled to the first and second recesses 154a and 154b and the first protrusion 155a of the cap plate 151, thereby preventing the positive electrode charging member 180 from rotating on the cap plate 151.

[0065] Although the aforementioned embodiments have been provided to implement the secondary battery according to the present invention, it should be understood that the embodiments described herein should be considered merely as descriptive and not for purposes of limitation, and that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the appended claims.

Claims

1. A secondary battery comprising: Electrode assembly; a housing in which the electrode assembly is accommodated; a cover plate coupled to the housing and sealing the electrode assembly; a terminal connected to the electrode assembly and exposed through the cover plate; as well as a charging member, interposed between the cover plate and the terminal, wherein the charging member comprises a conductive member interposed between the cover plate and the terminal and an insulating member interposed between the conductive member, the cover plate and the terminal, wherein the cover plate comprises a second recess, the conductive member comprises a second protrusion coupled to the second recess, and the insulating member comprises a first protrusion coupled to the second recess, and The first protrusion of the insulating member contacts the second protrusion of the conductive member at an outer side of the second protrusion of the conductive member to wrap the conductive member.

2. The secondary battery according to claim 1, wherein The conductive member includes a polymer and a conductive filler, the polymer includes polyphenylene sulfide (PPS), polyacetylene (PA), polyparaphenylene vinylene (PPV), polypyrrole (PPY), polyaniline (PANI), polythiophene (PT) or poly-3,4-polyethylenedioxythiophene (PEDOT), and the conductive filler includes carbon black, carbon fiber or carbon nanotube.

3. The secondary battery according to claim 1, wherein The electrical resistance of the conductive member is 1 kΩ to 1000 MΩ.

4. The secondary battery according to claim 1, wherein The insulating member includes a polymer including polycarbonate (PC), polyphenylene sulfide (PPS), polysulfone (PSF), polyethersulfone (PES), polyamideimide (PAI), or polyimide (PI).

5. The secondary battery according to claim 1, wherein The insulating member has a heat-resistant temperature of 120°C to 300°C.

6. The secondary battery according to claim 1, wherein The terminal includes a terminal column electrically connected to the electrode assembly and penetrating the cap plate, and a terminal plate coupled to the terminal column and located on the cap plate, and the conductive member contacts the cap plate, the terminal column, and the terminal plate.

7. The secondary battery according to claim 6, wherein The insulating member contacts the conductive member, the cap plate, and the terminal plate. 8 . The secondary battery according to claim 6 , further comprising a sealing gasket interposed between the terminal column and the cap plate, wherein the conductive member contacts the sealing gasket.

9. The secondary battery according to claim 1, wherein The cover plate further includes a first recess, and the conductive member further includes a first protrusion coupled to the first recess.

10. The secondary battery according to claim 1, wherein The cap plate further includes a first protrusion, and the conductive member further includes a first recess coupled to the first protrusion.

11. The secondary battery according to claim 1, wherein The conductive member further includes a second recess, and the insulating member further includes a second protrusion coupled to the second recess of the conductive member.

12. The secondary battery according to claim 8, wherein The conductive member is interposed between the sealing gasket and the insulating member.

13. The secondary battery according to claim 6, wherein The terminal column includes a flange, and the flange contacts the conductive member.

14. The secondary battery according to claim 6, wherein The terminal post is inserted into a terminal hole of the terminal plate and is riveted or welded to the terminal plate.

15. The secondary battery according to claim 6, wherein The conductive member includes a through hole, and the terminal column passes through the through hole of the conductive member.

16. The secondary battery according to claim 6, wherein The insulating member includes a third protrusion contacting a lower surface of the terminal plate and a fourth protrusion protruding inward from the third protrusion, and the fourth protrusion is coupled to a recess formed at the lower surface of the terminal plate.

17. The secondary battery according to claim 10, wherein The first recessed portion of the conductive member has a rectangular line shape.

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