Secondary battery

Abstract

A secondary battery according to an embodiment comprises: a case including an accommodation part; an electrode assembly accommodated in the case and including a core part; a first current collector plate disposed on top of the electrode assembly; and a second current collector plate disposed below the electrode assembly, wherein the first current collector plate or the second current collector plate includes a first electrolyte injection area including a first hole and a second electrolyte injection area including second holes, the first electrolyte injection area overlaps the core part, the diameter of the first electrolyte injection area is larger than that of the core part, and the first hole is disposed on the inner side of the innermost separator disposed on the side surface of the core part.

Description

secondary battery

[0001] The example relates to a secondary battery.

[0002] Unlike primary batteries, which cannot be recharged, secondary batteries are batteries capable of both charging and discharging. Low-capacity secondary batteries are used in small portable electronic devices such as smartphones, feature phones, laptop computers, digital cameras, and camcorders, while high-capacity secondary batteries are widely used as power sources for motor drive systems and power storage batteries in hybrid and electric vehicles. Such secondary batteries include an electrode assembly consisting of a positive electrode and a negative electrode, a case housing the assembly, and electrode terminals connected to the electrode assembly.

[0003] The information described above disclosed in the background technology of this invention is intended only to enhance understanding of the background of the present invention and may therefore include information that does not constitute prior art.

[0004] The embodiment provides a secondary battery having enhanced safety.

[0005] A secondary battery according to an embodiment includes a case including a receiving portion; an electrode assembly including a core portion and received in the case; a first current collector plate disposed on the upper part of the electrode assembly; and a second current collector plate disposed on the lower part of the electrode assembly, wherein the first current collector plate or the second current collector plate includes a first electrolyte injection area including a first hole and a second electrolyte injection area including a second hole, the first electrolyte injection area overlaps with the core portion, the diameter of the first electrolyte injection area is larger than the diameter of the core portion, and the first hole is disposed on the inner side of an innermost separator disposed on the side of the core portion.

[0006] The first current collector plate includes a first electrolyte injection area including the first hole and a second electrolyte injection area including the second hole, wherein the first electrolyte injection area is positioned in the central area of ​​the first current collector plate and the second electrolyte injection area is positioned in the edge area of ​​the first current collector plate.

[0007] The first hole is formed by a first opening area and a second opening area, the first electrolyte injection area includes a closed area, the first opening area is positioned in the central area of ​​the first electrolyte injection area, and the second opening area protrudes from the first opening area.

[0008] The first opening area is surrounded by the second opening area and the closed area.

[0009] The outer diameter of the circle connecting the second opening area is positioned on the inner side of the innermost separator.

[0010] The first opening region and the second opening region are formed integrally.

[0011] The above closed area is placed in a first electrolyte injection area other than the above first opening area and the above second opening area.

[0012] The diameter of the first electrolyte injection area is 3.5 mm to 4.5 mm, and the diameter of the innermost separator is 2.7 mm to 3.4 mm.

[0013] The width of the second opening area is smaller than the width of the first opening area.

[0014] The sum of the areas of the first opening area and the second opening area has a first area, the closed area has a second area, and the second area is larger than the first area.

[0015] The first area is 25% to 49% of the first electrolyte injection area, and the second area is 51% to 75% of the first electrolyte injection area.

[0016] The first hole comprises a first-1 hole and a plurality of first-2 holes, and the first current collector comprises a first electrolyte injection area comprising the first-1 hole and the first-2 hole; and a second electrolyte injection area comprising a second hole, wherein the first electrolyte injection area is disposed in the central area of ​​the first current collector and the second electrolyte injection area is disposed in the edge area of ​​the second current collector, the first-1 hole is formed by a first opening area and a second opening area, the first electrolyte injection area includes a closed area, the first opening area is disposed in the central area of ​​the first electrolyte injection area, the second opening area protrudes from the first opening area, and the first-2 hole is disposed on the inner side of the outer diameter of a circle connecting the second opening area.

[0017] The diameter of the first and second holes is smaller than the first opening area and the second opening area.

[0018] The first current collector plate includes a first electrolyte injection area including the first hole and a second electrolyte injection area including the second hole, the first electrolyte injection area is positioned in the central area of ​​the first current collector plate and the second electrolyte injection area is positioned in the edge area of ​​the second current collector plate, the first hole is formed by a first opening area and a second opening area, the first electrolyte injection area includes a closed area, the first opening area is positioned in the central area of ​​the first electrolyte injection area and the second opening area is spaced apart from the first opening area.

[0019] The second opening region is positioned between the outer diameter of the first opening region and the outer diameter of the innermost separator.

[0020] The first opening area and the second opening area are formed with the same shape, and the size of the second opening area is smaller than the size of the first opening area.

[0021] The first current collector plate includes a first electrolyte injection area including the first hole and a second electrolyte injection area including the second hole, the first electrolyte injection area is disposed in the central area of ​​the first current collector plate and the second electrolyte injection area is disposed in the edge area of ​​the second current collector plate, the first hole is formed by a first opening area and a second opening area, the first electrolyte injection area includes a closed area, the first opening area is disposed in the central area of ​​the first electrolyte injection area, the closed area is formed in a mesh shape, and the second opening area is disposed in an open area of ​​the mesh shape.

[0022] The above secondary battery further includes a cap assembly that seals the case.

[0023] The second current collector plate includes a first electrolyte injection area including the first hole and a second electrolyte injection area including the second hole, wherein the first electrolyte injection area is positioned in the central area of ​​the second current collector plate and the second electrolyte injection area is positioned in the edge area of ​​the second current collector plate.

[0024] The above secondary battery further includes a cap plate that seals the case.

[0025] The current collector plate of the secondary battery according to the embodiments includes a first electrolyte injection area having a set size.

[0026] The first electrolyte injection area includes an opening area and a closed area. The opening area has a set size. Accordingly, the electrolyte can be easily injected into the case through the first electrolyte injection area. Thus, the electrode assembly can be sufficiently impregnated with the electrolyte.

[0027] The above-mentioned opening region includes a first opening region and a second opening region. The first opening region is positioned in the central region of the first electrolyte injection region. The second opening region extends from the first opening region in the direction of the outer diameter of the electrolyte injection region. The outer diameter of the circle extending the second opening regions may be smaller than the diameter of the innermost separator. Accordingly, the end of the second opening region may be positioned inside the innermost separator. Thus, the amount of electrolyte directly delivered to the innermost separator may be reduced. Consequently, damage to the innermost separator may be prevented.

[0028] The above-mentioned closed region has a set size. The pressure generated when injecting the electrolyte can be dispersed through the above-mentioned closed region. Accordingly, the pressure transmitted to the innermost separator can be reduced. Therefore, damage to the innermost separator due to pressure can be prevented.

[0029] However, the effects obtainable through the present invention are not limited to those described above, and other unmentioned technical effects will be clearly understood by those skilled in the art from the description of the invention below.

[0030] FIG. 1 is a perspective view of a secondary battery according to an embodiment.

[0031] FIG. 2 is an exploded perspective view of a secondary battery according to an embodiment.

[0032] Figure 3 is a cross-sectional view of the AA' region of Figure 1.

[0033] FIG. 4 is a top view of the first collector plate according to an embodiment.

[0034] Figure 5 is an enlarged view of area A of Figure 4.

[0035] FIG. 6 is a diagram illustrating the movement of pressure and electrolyte in the first collector plate according to an embodiment.

[0036] Figure 7 is another enlarged view of area A in Figure 4.

[0037] FIG. 8 is a top view of a first current collector plate according to another embodiment.

[0038] Figure 9 is an enlarged view of area B of Figure 8.

[0039] FIG. 10 is a top view of a first current collector plate according to another embodiment.

[0040] Figure 11 is an enlarged view of area C of Figure 10.

[0041] FIG. 12 is a top view of a first current collector plate according to another embodiment.

[0042] Figure 13 is an enlarged view of area D of Figure 12.

[0043] FIG. 14 is a perspective view of a secondary battery according to another embodiment.

[0044] Figure 15 is a cross-sectional view of the BB' region of Figure 14.

[0045] FIG. 16 is a perspective view of a battery module including secondary batteries according to an embodiment.

[0046] FIGS. 17 and FIGS. 18 are perspective views of a battery pack including a battery module according to an embodiment.

[0047] FIGS. 19 and FIGS. 20 are a perspective view and a side view of a vehicle including a battery pack according to an embodiment.

[0048] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0049] The embodiments of the present invention are provided to more fully explain the invention to those skilled in the art, and the following embodiments may be modified in various different forms, and the scope of the invention is not limited to the following embodiments. Rather, these embodiments are provided to make the disclosure more faithful and complete and to fully convey the spirit of the invention to those skilled in the art.

[0050] Additionally, in the drawings below, the thickness or size of each layer is exaggerated for convenience and clarity of explanation, and like reference numerals in the drawings refer to like elements. As used herein, the term "and / or" may include any one of the listed items and all combinations of one or more thereof. Furthermore, in this specification, the meaning of "may be connected" refers not only to cases where Member A and Member B are directly connected, but also to cases where Member C is interposed between Member A and Member B so that Member A and Member B are indirectly connected.

[0051] The terms used herein are for describing specific embodiments and are not intended to limit the invention. As used herein, the singular form may include the plural form unless the context clearly indicates otherwise. Additionally, as used herein, “comprise, include” and / or “comprising, including” specify the presence of the mentioned features, numbers, steps, actions, parts, elements, and / or groups thereof, and do not exclude the presence or addition of one or more other features, numbers, actions, parts, elements, and / or groups.

[0052] Although terms such as "first," "second," etc. are used in this specification to describe various components, parts, regions, layers, and / or parts, it is obvious that these components, parts, regions, layers, and / or parts should not be limited by these terms. These terms are used solely to distinguish one component, part, region, layer, or part from another region, layer, or part. Accordingly, the first component, part, region, layer, or part described below may refer to the second component, part, region, layer, or part without departing from the teachings of the present invention.

[0053] Spatial terms such as "beneath," "below," "lower," "above," and "upper" may be used to facilitate understanding of one element or feature depicted in the drawings and another element or feature. These spatial terms are intended to facilitate understanding of the invention according to various process or usage conditions of the invention and are not intended to limit the invention. For example, if an element or feature in the drawings is inverted, an element or feature described as "beneath" or "below" becomes "upper" or "on top." Therefore, "beneath" is a concept that encompasses "upper" or "below."

[0054] In the following description, the width direction (diameter direction) of the above case is defined as the X direction. Additionally, the height direction of the above case is defined as the Y direction.

[0055] Hereinafter, a secondary battery according to embodiments is described with reference to the drawings.

[0056] Referring to FIGS. 1 to 3, the secondary battery (1000) may include a case (100), an electrode assembly (200), a lead tab (350), a cap assembly (300), an insulating gasket (500), and a current collector plate.

[0057] The above case (100) forms the overall exterior of the secondary battery (1000). The above case (100) may include a conductive metal such as aluminum, an aluminum alloy, or nickel-plated steel. Additionally, the above case (100) may include a space in which an electrode assembly (200) is accommodated. For example, the above case (100) may include a receiving portion, and the electrode assembly (200) may be accommodated inside the receiving portion.

[0058] The above case (100) can be formed in various shapes. For example, the above case (100) can be formed in a circular, rectangular, or pouch shape. However, the embodiments are not limited thereto. For convenience of explanation, the above case (100) is described below as being formed in a circular shape.

[0059] The electrode assembly (200) may include a first electrode (210), a second electrode (220), and a separator (230). The separator (230) may be placed between the first electrode (210) and the second electrode (220). Additionally, the electrode assembly (200) may be wound in the form of a jelly roll. The electrode assembly (200) may be placed in a receiving portion of the case.

[0060] The first electrode (210) may include a first substrate (211) and a first active material layer (212) disposed on the first substrate (211). The first substrate (211) may include one side and another side opposite to the one side. The first active material layer (212) may be disposed on at least one of the one side and the other side. The first substrate (211) may include a first non-blocking portion (211a). The first active material layer (212) is not disposed on the first non-blocking portion (211a). The first non-blocking portion (211a) may be notched. Accordingly, the first non-blocking portion (211a) may form a first substrate tab.

[0061] The second electrode (220) may include a second substrate (221) and a second active material layer (222) disposed on the second substrate (221). The second substrate (221) may include one side and another side opposite to the one side. The second active material layer (222) may be disposed on at least one of the one side and the other side. The second substrate (221) may include a second non-substrate (221a). The second active material layer (222) is not disposed on the second non-substrate (221a). The second non-substrate (221a) may be notched. Accordingly, the second non-substrate (221a) may form a second substrate tab.

[0062] The first electrode (210) may be an anode. For example, the first substrate (211) may include aluminum. Additionally, the first active material layer (212) may include a transition metal oxide. The second electrode (220) may be a cathode. For example, the second substrate (221) may include copper or nickel. Additionally, the second active material layer (222) may include graphite.

[0063] The separator (230) can prevent a short circuit between the first electrode (210) and the second electrode (220) while allowing the movement of lithium ions. For example, the separator (230) may include a polyethylene film, a polypropylene film, or a polyethylene-polypropylene film.

[0064] The above case (100) can accommodate the electrode assembly (200) and the electrolyte. Additionally, the above case (100) and the above cap assembly (300) can form the external shape of a secondary battery. The above case (100) may include a cylindrical body portion (110) and a bottom portion (120) connected to one side of the body portion (110). A beading portion (130) deformed toward the inside may be formed on the body portion (110). Additionally, a crimping portion (140) bent toward the inside may be formed on the opening end of the body portion (110).

[0065] Movement of the electrode assembly (200) placed inside the case (100) can be prevented or reduced by the beading portion (130). Additionally, the insulating gasket (500) and the cap assembly (300) can be easily supported by the beading portion (130). The crimping portion (140) can press the edge of the cap assembly (300) through the insulating gasket (500). Accordingly, the fixing force of the cap assembly (300) can be improved.

[0066] The cap assembly (300) is secured to the inside of the crimping portion (140) through the insulating gasket (500). Accordingly, the cap assembly (300) can seal the case (100). The cap assembly (300) may include a cap up (310), a safety vent (320), a cap down (330), and an insulating member (340).

[0067] The cap up (310) may be located at the uppermost side of the cap assembly (300). The cap up (310) protrudes upward in a convex manner. The cap up (310) may include a terminal portion connected to an external circuit. An outlet (310a) for discharging gas may be located around the terminal portion.

[0068] The safety vent (320) may be located below the cap up (310). The safety vent (320) may include a protrusion that protrudes downwardly in a convex manner. The protrusion may be connected to the cap down (330). Additionally, the safety vent (320) may include at least one notch located around the protrusion.

[0069] Gas may be generated due to an increase in the internal temperature of the secondary battery. Accordingly, the protrusion may be deformed upward by the pressure of the gas. Accordingly, the protrusion and the cap down (330) may be separated. Additionally, the safety vent (320) may be cut along the notch. The gas may be released to the outside through the cut safety vent (320). Accordingly, the explosion of the secondary battery may be prevented.

[0070] The cap down (330) may be located below the safety vent (320). The cap down (330) may have a first opening for exposing the protrusion of the safety vent and a second opening for gas discharge. The insulating member (340) is positioned between the safety vent (320) and the cap down (330). The safety vent (320) and the cap down (330) may be insulated by the insulating member (340).

[0071] Lithium ions are generated in the first electrode (210) and the second electrode (220) through an electrochemical reaction. The electrolyte serves to enable the movement of lithium ions. The electrolyte may be a non-aqueous organic electrolyte, which is a mixture of a lithium salt and a high-purity organic solvent. Alternatively, the electrolyte may be a polymer using a polymer electrolyte or a solid electrolyte.

[0072] The electrode assembly (200) may include a core portion (250). Specifically, the electrode assembly (200) is wound in a unidirectional manner. Accordingly, a core portion (250) may be formed at the center of the electrode assembly. When injecting the electrolyte, the electrolyte can be easily injected through the core portion (250). For example, the electrolyte can be injected into the core portion through the electrolyte injection portion of the first current collector plate. Additionally, when high-temperature gas is generated inside the secondary battery, the gas can be easily moved to the outside of the secondary battery through the core portion (250). A separator may be disposed on the inner surface of the core portion (250). The separator disposed on the inner surface of the core portion (250) may be the innermost separator (230a).

[0073] The current collector plate is positioned on the upper and lower portions of the electrode assembly (200). The current collector plate may include a first current collector plate (710) and a second current collector plate (720). The first current collector plate (710) may be positioned on the upper portion of the electrode assembly (200). Specifically, the first current collector plate (710) may be positioned between the electrode assembly (200) and the cap assembly (300). The second current collector plate (720) may be positioned on the lower portion of the electrode assembly (200). Specifically, the second current collector plate (720) may be positioned between the electrode assembly (200) and the bottom portion (120) of the case.

[0074] The area of ​​the first current collector plate (710) may be less than or equal to the area of ​​the upper surface of the electrode assembly. Additionally, the area of ​​the second current collector plate (720) may be less than or equal to the area of ​​the lower surface of the electrode assembly.

[0075] The first current collector plate (710) is connected to the first electrode (210). Specifically, the first current collector plate (710) is electrically connected to the first substrate tab. For example, the first current collector plate (710) and the first substrate tab can be joined by welding.

[0076] The first current collector plate (710) can be connected to the cap assembly (300). Specifically, the first current collector plate (710) and the cap assembly (300) can be connected by the lead tab (350). One end of the lead tab (350) and the first current collector plate (710) can be joined by welding. The other end of the lead tab (350) and the cap down (330) can be joined by welding. Accordingly, the first current collector plate (710) and the cap assembly (300) can be electrically connected by the lead tab (350). Thus, the first current collector plate (710) can serve as a passage for current flow between the first electrode (210) and the cap assembly (300). Accordingly, the terminal portion of the cap assembly can become the positive electrode.

[0077] The second current collector plate (720) can be connected to the second electrode (220). Specifically, the second current collector plate (720) can be electrically connected to the second substrate tab. For example, the second current collector plate (720) and the second substrate tab can be joined by welding. Additionally, the second current collector plate (720) can be connected to the bottom portion (120) of the case. For example, the second current collector plate (720) and the bottom portion (120) of the case can be joined by welding. Thus, the second current collector plate (720) can serve as a passage for current flow between the second electrode (220) and the case (110). Accordingly, the case can be the negative electrode.

[0078] The first current collector plate (710) may include an electrolyte injection area. Specifically, the first current collector plate (710) may include a first electrolyte injection area (710a) and a second electrolyte injection area (710b). The electrolyte may be injected into the interior of the case through the electrolyte injection area.

[0079] The first electrolyte injection area (710a) may overlap with the core portion (250). Pressure may be generated during the process of injecting the electrolyte. A separator is disposed on the inner surface of the core portion. Accordingly, the area of ​​the innermost separator (230a) close to the first current collector plate may be damaged by the pressure. As a result, the first electrode and the second electrode may be short-circuited.

[0080] The above pressure is determined by the opening area formed in the first electrolyte injection area. Specifically, the pressure is proportional to the size of the opening area. To reduce the pressure, the size of the opening area can be reduced. However, there is a problem that the injection speed of the electrolyte is reduced.

[0081] The embodiment controls the opening area of ​​the first electrolyte injection area. Accordingly, damage to the separator caused by the pressure can be prevented while maintaining the electrolyte injection speed.

[0082] Hereinafter, the first collector plate will be described in detail with reference to the drawings.

[0083] Referring to FIGS. 4 to 6, the first current collector plate (710) may include a first electrolyte injection area (710a) and a second electrolyte injection area (710b).

[0084] The first electrolyte injection area (710a) may be positioned in the central area of ​​the first current collector plate (710), and the second electrolyte injection area (710b) may be positioned in the edge area of ​​the first current collector plate (710). The first electrolyte injection area (710a) may overlap with the core portion. Specifically, the first electrolyte injection area (710a) may overlap with the core portion in the Y direction.

[0085] A first hole (H1) may be formed in the first electrolyte injection area (710a). At least one second hole (H2) may be formed in the second electrolyte injection area (710b). The electrolyte may move into the interior of the case through the first hole (H1) and the second hole (H2). Accordingly, the electrode assembly (200) may be impregnated with the electrolyte.

[0086] Referring to FIG. 5, the first electrolyte injection area (710a) may include an opening area and a closed area (PR). The opening area may include a first opening area (OA1) and a second opening area (OA2). The first electrolyte injection area (710a) may have a set size. Specifically, the diameter of the first electrolyte injection area may be larger than the diameter of the core portion (250). Accordingly, the first electrolyte injection area may be positioned outside the innermost separator (230a). That is, the diameter of the first electrolyte injection area may be larger than the diameter of the innermost separator (230a). For example, the diameter of the electrolyte injection area (710a) may be 3.5 mm to 4.5 mm, 3.7 mm to 4.3 mm, or 3.9 mm to 4.1 mm. In addition, the diameter of the innermost separator (230a) may be 2.7 mm to 3.4 mm, 2.9 mm to 3.4 mm, or 3.2 mm to 3.4 mm.

[0087] The first hole (H1) is formed by the first opening area (OA1) and the second opening area (OA2). The first opening area (OA1) may be formed in a circular shape. The first opening area (OA1) may be positioned in the central area of ​​the first electrolyte injection area (710a). A portion of the first opening area (OA1) may be surrounded by the closed area (PR). Additionally, a portion of the first opening area (OA1) may be surrounded by the second opening area (OA2). That is, the second opening area (OA2) and the closed area (PR) may surround the first opening area (OA1).

[0088] The second opening region (OA2) may protrude from the first opening region (OA1). Specifically, the second opening region (OA2) may extend from the outer diameter of the first opening region (OA1) in the direction of the outer diameter of the first electrolyte injection region (710a). The second opening region (OA2) may include a plurality of opening regions.

[0089] The end (E) of the second opening region (OA2) may be positioned inside the innermost separator (230a). Specifically, the outer diameter (OR) of a circle connecting a plurality of second opening regions (OA2) may be positioned inside the innermost separator (230a). That is, the outer diameter (OR) may be smaller than the outer diameter of the innermost separator (230a).

[0090] Accordingly, the amount of electrolyte directly delivered from the second opening region (OA2) to the innermost separator (230a) can be reduced. Accordingly, damage to the innermost separator (230a) by pressure can be prevented.

[0091] The first opening region (OA1) and the second opening region (OA2) can be connected. That is, the first opening region (OA1) and the second opening region (OA2) can be formed integrally.

[0092] The above closed area (PR) may be placed in an area other than the first open area (OA1) and the second open area (OP2). That is, the above closed area (PR) is an area where the first collector plate (710) is not opened. That is, the above closed area (PR) is an area formed integrally with the first collector plate (710). Accordingly, the above closed area (PR) may be placed on both the inner and outer sides of the innermost separator (230a).

[0093] The electrolyte is injected into the interior of the case through the electrolyte injection area. For example, the electrolyte can be injected into the vacuum case through a nozzle. Subsequently, pressure can be applied to the case. By doing so, the electrolyte can seep through the pores of the electrode. Accordingly, the electrode assembly (200) can be immersed in the electrolyte.

[0094] The first electrolyte injection area overlaps with the core portion. Accordingly, the tip of the innermost separator (230a) may be damaged by the pressure. Consequently, the first electrode and the second electrode may short-circuit, causing a fire in the secondary battery.

[0095] The above closed region (PR) can reduce the pressure generated when injecting the electrolyte. Referring to FIG. 6, the electrolyte is injected into the interior of the case through the first hole (H1). In detail, the electrolyte is injected through the first opening region (OA1) and the second opening region (OA2).

[0096] The pressure generated during the injection of the electrolyte can be dispersed in multiple directions. Specifically, the pressure is dispersed in the direction of the first hole (H1) and the protrusion (PR). Accordingly, the pressure transmitted to the innermost separator (230a) adjacent to the first hole (H1) can be reduced. Thus, damage to the innermost separator (230a) by pressure can be reduced or prevented.

[0097] Accordingly, in the secondary battery according to the embodiment, damage to the separator occurring during the electrolyte injection process can be prevented. Therefore, fire in the secondary battery can be prevented. Accordingly, the secondary battery according to the embodiment can have enhanced safety.

[0098] FIG. 7 is a drawing illustrating the first electrolyte injection area of ​​another embodiment.

[0099] Referring to FIG. 7, the second opening area (OA2) may be smaller than the first opening area (OA1). Specifically, the first opening area (OA1) may have a first width (W1). The first width (W1) may be the maximum width of the first opening area. That is, the first width (W1) may be the maximum diameter of the first opening area. Additionally, the second opening area (OA2) may have a second width (W2). The second width (W2) may be the maximum width of the second opening area.

[0100] The second width (W2) may be smaller than the first width (W1). For example, the second width (W2) may be 20% to 50%, 25% to 45%, or 30% to 40% of the first width (W1). For example, the first width (W1) may be 1.5 mm to 2 mm, and the second width (W2) may be 0.3 mm to 1 mm.

[0101] The second opening region (OA2) moves away from the first opening region (OA1) and approaches the innermost separator (230a). Accordingly, if the size of the second opening region (OA2) is large, the pressure of the electrolyte delivered to the innermost separator (230a) may be increased. Accordingly, other embodiments may control the second opening region to a set size. Accordingly, damage to the innermost separator may be prevented.

[0102] The above-mentioned opening area and the above-mentioned closing area (PR) may be arranged with a set area. Specifically, the above-mentioned opening area may have a first area. The first area is the sum of the areas of the first opening area (OA1) and the second opening area (OA2). The above-mentioned closing area (PR) may have a second area. The sum of the first area and the second area is the area of ​​the first electrolyte injection area.

[0103] The first area and the second area may differ. Specifically, the second area may be larger than the first area. The second area may exceed 50% of the area of ​​the first electrolyte injection area. Specifically, the second area may be 51% to 75% of the first electrolyte injection area. Additionally, the first area may be 25% to 49% of the first electrolyte injection area.

[0104] If the second area is less than 51% of the first electrolyte injection area, the pressure generated when injecting the electrolyte may not be effectively dispersed by the protrusion. Consequently, the tip of the innermost separator may be damaged. If the second area exceeds 75% of the first electrolyte injection area, the area of ​​the opening region becomes narrower. Consequently, the electrolyte may not be effectively injected into the case. Therefore, the process efficiency of injecting the electrolyte may be reduced. Additionally, the electrode assembly may not be sufficiently impregnated with the electrolyte.

[0105] Meanwhile, the size of the second hole (H2) may be the same as or different from the first opening area. For example, the size of the second hole (H2) may be smaller or larger than the first opening area. The electrolyte injected through the second hole (H2) is not directly delivered to the innermost separator. Accordingly, the size of the second hole (H2) may vary depending on the electrolyte injection process.

[0106] The current collector plate of the secondary battery according to the embodiments includes a first electrolyte injection area having a set size.

[0107] The first electrolyte injection area includes an opening area and a closed area. The opening area has a set size. Accordingly, the electrolyte can be easily injected into the case through the first electrolyte injection area. Thus, the electrode assembly can be sufficiently impregnated with the electrolyte.

[0108] The above opening region includes the first opening region and the second opening region. The first opening region is positioned in the central region of the first electrolyte injection region. The second opening region extends from the first opening region in the direction of the outer diameter of the electrolyte injection region. The outer diameter of the circle extending the second opening regions may be smaller than the diameter of the innermost separator. Accordingly, the end of the second opening region may be positioned inside the innermost separator. Thus, the amount of electrolyte directly delivered to the innermost separator may be reduced. Consequently, damage to the innermost separator may be prevented.

[0109] The above-mentioned closed region has a set size. The pressure generated when injecting the electrolyte can be dispersed through the above-mentioned closed region. Accordingly, the pressure transmitted to the innermost separator can be reduced. Therefore, damage to the innermost separator due to pressure can be prevented.

[0110] Hereinafter, a secondary battery according to another embodiment will be described with reference to FIGS. 8 to 13. Descriptions identical to those of the previously described embodiment will be omitted. The same reference numerals will be assigned to components identical to those of the previously described embodiment.

[0111] Referring to FIGS. 8 and 9, the first hole (H1) may include a first-1 hole (H1-1) and at least one first-2 hole (H1-2). For example, the first hole (H1) may include one first-1 hole (H1-1) and a plurality of first-2 holes (H1-2).

[0112] The above 1-1 hole (H1-1) may correspond to the 1-1 hole (H1) of the previously described embodiment. That is, other embodiments may include the above 1-2 hole (H1-2) differently from the previously described embodiment. The above 1-2 hole (H1-2) may be spaced apart from the above 1-1 hole (H1-1).

[0113] The first-second hole (H1-2) may be positioned inside the outer diameter (OR) of a circle connecting a plurality of second opening regions (OA2). The first-second hole (H1-2) may be formed by penetrating a closed region (PR) positioned inside the outer diameter (R). Specifically, the first-second hole (H1-2) may be formed by penetrating a closed region (PR) between adjacent second opening regions (OA2).

[0114] The first-second hole (H1-2) may have a set size. The diameter of the first-second hole (H1-2) may be smaller than the diameter of the first opening area (OA1). The diameter of the first-second hole (H1-2) may be smaller than the width of the second opening area (OA2). The diameter of the first-second hole (H1-2) may be smaller than the second hole (H2). For example, the diameter of the first-second hole (H1-2) may be 0.4 mm to 0.8 mm.

[0115] A first current collector plate of a secondary battery according to another embodiment further includes a first-2 hole. The electrolyte can be injected more easily through the first-2 hole. Specifically, the area through which the electrolyte can pass into the case is increased by the first-2 hole. Accordingly, the process efficiency of injecting the electrolyte can be improved.

[0116] In addition, the first and second holes are formed with a set size. Specifically, the first and second holes are formed smaller than the other holes. Accordingly, damage to the innermost separator by the first and second holes can be prevented.

[0117] Referring to FIGS. 10 and FIGS. 11, a first hole (H1) may be formed in the first electrolyte injection area (710a).

[0118] The first hole (H1) may include a first opening area (OA1) and at least one second opening area (OA2). For example, the first hole (H1) may include one first opening area (OA1) and a plurality of second opening areas (OA2).

[0119] The first opening region (OA1) above corresponds to the first opening region of the previously described embodiment.

[0120] Unlike the embodiment described above, the second opening region (OA2) may not be connected to the first opening region. That is, the second opening region (OA2) may be separated from the first opening region. Specifically, the second opening region (OA2) may be spaced apart from the first opening region (OA1). The second opening region (OA2) may be formed by penetrating the closed region (PR) outside the first opening region (OA1). Specifically, the second opening region (OA2) may be positioned between the outer diameter of the first opening region (OA1) and the outer diameter of the innermost separator.

[0121] The first opening region (OA1) and the second opening region (OA2) may be formed with the same shape. Specifically, the first opening region (OA1) and the second opening region (OA2) may be formed in a circular shape.

[0122] The size of the second opening area (OA2) may be smaller than the first opening area (OA1). Specifically, the diameter of the second opening area may be smaller than the diameter of the first opening area. For example, the diameter of the second opening area may be 20% to 50%, 25% to 45%, or 30% to 40% of the diameter of the first opening area. For example, the diameter of the first opening area may be 1.5 mm to 2 mm, and the diameter of the second opening area may be 0.3 mm to 1 mm.

[0123] The second opening region (OA2) may be positioned inside the first electrolyte injection region. The second opening region (OA2) may be positioned inside the innermost separator. That is, the outer diameter (OR) of the circle connecting the plurality of second opening regions (OA2) may be smaller than the outer diameter of the first electrolyte injection region and the outer diameter of the innermost separator.

[0124] In another embodiment, a first current collector plate of a secondary battery includes a first hole comprising a first opening region and a second opening region. The first opening region and the second opening region are separated. Accordingly, the first opening region and the second opening region are formed by different processes. Accordingly, the size of a plurality of second opening regions can be formed uniformly. In addition, the shape of the first opening region and the second opening region can be identical. Therefore, the first opening region and the second opening region can be formed through the same process equipment.

[0125] In addition, the first opening region and the second opening region have a set size. Accordingly, the electrolyte is easily injected through the first opening region and the second opening region. In addition, the pressure generated during the injection of the electrolyte can be easily dispersed through the closed region. Accordingly, damage to the innermost separator can be prevented.

[0126] Referring to FIGS. 12 and 13, a first hole (H1) may be formed in the first electrolyte injection area (710a).

[0127] The first hole (H1) may include a first opening area (OA1) and at least one second opening area (OA2). For example, the first hole (H1) may include one first opening area (OA1) and a plurality of second opening areas (OA2).

[0128] The first opening region (OA1) above corresponds to the first opening region of the previously described embodiment.

[0129] Unlike the embodiment described above, the second opening region (OA2) may include a region that is not connected to the first opening region. Specifically, at least one second opening region (OA2) may be spaced apart from the first opening region (OA1).

[0130] A closed area (PR) is formed on the outer side of the first opening area (OA1). The closed area (PR) may be arranged in multiple directions. For example, the closed area (PR) may be formed in a mesh shape. The second opening area (OA2) is formed in the open area of ​​the mesh shape. That is, the second opening area (OA2) may be surrounded by the closed area (PR).

[0131] The second opening region (OA2) may be positioned between the outer diameter of the first opening region (OA1) and the outer diameter of the innermost separator. That is, a plurality of second opening regions (OA2) may be positioned inside the innermost separator.

[0132] The first opening area (OA1) and the second opening area (OA2) may be formed in different shapes. For example, the first opening area (OA1) may be formed in a circular shape. Additionally, the second opening area (OA2) may be formed in a rectangular shape.

[0133] The size of the second opening area (OA2) may be smaller than the first opening area (OA1). Specifically, the width of the second opening area may be smaller than the diameter of the first opening area.

[0134] In another embodiment, a first current collector plate of a secondary battery includes a first hole comprising a first opening region and a second opening region. The second opening region is formed simultaneously with the process of forming the closed region. Specifically, the second opening region is naturally formed while forming the closed region. In addition, the size of the second opening region varies depending on the arrangement of the closed region. Therefore, the size of the second opening region can be easily changed. Thus, process efficiency can be improved.

[0135] In addition, the first opening region and the second opening region have a set size. Accordingly, the electrolyte is easily injected through the first opening region and the second opening region. In addition, the pressure generated during the injection of the electrolyte can be easily dispersed through the closed region. Accordingly, damage to the innermost separator can be prevented.

[0136] In the preceding description, embodiments in which an electrolyte injection area is formed on the first current collector plate were described. However, depending on the type of the secondary battery, an electrolyte injection area may be formed on the second current collector plate.

[0137] Referring to FIGS. 14 and 15, a secondary battery (1000) according to another embodiment may include a case (100), an electrode assembly (200), a current collector plate (700), a cap plate (400), a terminal portion (600), and an insulator (800).

[0138] The above case (100) can accommodate the electrode assembly (200). The above case (100) can be formed in a cylindrical shape.

[0139] The above case (100) may include an upper surface (110) and a side surface (120).

[0140] The upper surface (110) may be formed in a circular shape. The upper surface (110) may include a terminal hole. For example, the terminal hole may be positioned in the center of the upper surface (110).

[0141] The side portion (120) may be connected to the upper portion (110). The side portion (120) and the upper portion (110) may be formed integrally. The upper portion (110) may be positioned on the upper part of the side portion (120). The lower part of the side portion (120) may be open. Accordingly, the lower part of the case (100) may be open. Accordingly, the electrode assembly (200) may be accommodated in the case (100) through the opening.

[0142] The side portion (120) may include a beading portion (130) and a crimping portion (140). The beading portion (130) may be adjacent to the lower part of the side portion (120). The beading portion (130) may be formed concavely inward from the side portion (120). An end spaced apart from the beading portion (130) may be bent toward the inside of the case (100) to form a crimping portion (140). The electrode assembly (200) is prevented from moving out of the case (100) by the beading portion (130). The cap plate (400) may be placed between the beading portion (130) and the crimping portion (140). The cap plate (400) may be fixed by the crimping portion (140).

[0143] The above current collector plate (700) can be connected to the above electrode assembly (200).

[0144] The first current collector plate (710) can be electrically connected to the first electrode (210). For example, the first current collector plate (710) can be connected to the first substrate tab. Accordingly, the first electrode (210) and the terminal portion (600) can be electrically connected by the first current collector plate (310). That is, the first current collector plate (710) becomes a passage for current flow between the first electrode (210) and the terminal portion (600).

[0145] The second current collector plate (720) may be electrically connected to the second electrode (220). For example, the second current collector plate (720) may be connected to the second substrate tab. The second current collector plate (720) and the case (100) may be electrically connected. However, the second current collector plate (720) is not electrically connected to the cap plate (400).

[0146] Accordingly, the second electrode (220) and the case (100) can be electrically connected by the second current collector plate (710). That is, the second current collector plate (720) becomes a passage for current flow between the second electrode (220) and the case (100).

[0147] The terminal portion (600) can be inserted into the terminal hole. A portion of the terminal portion (600) may be exposed outside the terminal hole.

[0148] The terminal portion (600) can be electrically connected to the first electrode (210) by the first current collector plate (310). The terminal portion (600) can be joined to the upper surface portion (110) by a riveting method. That is, the terminal portion (600) can be a riveted terminal.

[0149] The terminal portion (600) can be inserted into the terminal hole from the outside of the case (100) toward the inside. For example, while the terminal portion (600) is inserted into the terminal hole, the inner end of the terminal portion (600) can be compressed and deformed by processing such as pressing or spinning. Accordingly, the terminal portion (600) can be in close contact with the upper surface portion (110) of the case (100). Thus, one end of the terminal portion (600) can be positioned on the outside of the case (100), and the other end can be positioned on the inside of the case (100).

[0150] An insulator (800) may be placed between the terminal portion (600) and the case (100). Accordingly, a short circuit between the terminal portion (600) and the case (100) can be prevented.

[0151] The cap plate (400) is positioned at the lower part of the side portion (120). The cap plate (400) is positioned over the opening of the case (100). Accordingly, the case (100) can be sealed by the cap plate. An insulating gasket (500) may be positioned between the case (100) and the cap plate (400).

[0152] The above cap plate may include a notch (401). The notch may break at a set pressure.

[0153] The electrolyte is injected into the above case. Specifically, the electrolyte is injected before the cap plate is placed. For example, the second current collector (720) may include an electrolyte injection area. Specifically, the second current collector (720) may include the same electrolyte injection area as the first current collector described above. Thus, when the electrolyte is injected, damage to the innermost separator can be prevented.

[0154] The above secondary battery can be used in portable small electronic devices such as smartphones, feature phones, laptop computers, digital cameras, and camcorders. In addition, a battery module and a battery pack comprising a plurality of secondary batteries can be used as a power source for driving a motor and as a battery for storing power in a hybrid or electric vehicle.

[0155] Hereinafter, a battery module including secondary batteries according to embodiments will be described with reference to FIG. 16.

[0156] Referring to FIG. 16, a battery module (2000) according to an embodiment comprises terminal portions (261, 262), a plurality of secondary batteries (1000) arranged in one direction, a connection tab (20) connecting a secondary battery (1000a) to an adjacent secondary battery (1000b), and a protection circuit module (30) having one end connected to the connection tab (20). The protection circuit module (30) may be a Battery Management System (BMS). The connection tab (20) includes a body portion that contacts the electrode portion between adjacent secondary batteries (1000a, 1000b) and an extension portion that extends from the body portion and is connected to the protection circuit module (30). The connection tab (20) may be a busbar.

[0157] First, the secondary battery (1000) may include the secondary batteries described above. On one side of the secondary battery (1000), a terminal portion (261, 262) electrically connected to a connection tab (20) and a vent (850) serving as a passage for discharging gas generated internally may be provided. The terminal portion (261, 262) of the secondary battery (1000) may be a positive terminal (261) and a negative terminal (262) having different polarities, and the terminal portions (261, 262) of adjacent secondary batteries (1000a, 1000b) may be electrically connected in series or parallel by the connection tab (20) described below. Meanwhile, although a series connection has been described as an example above, it is not limited to this structure, and various connection structures may be adopted as needed. In addition, the number and arrangement of secondary batteries are not limited to the structure shown in FIG. 16 and can be changed as needed.

[0158] A plurality of secondary batteries (1000) may be arranged in one direction such that the wide surfaces of the secondary batteries (1000) face each other, and the arranged plurality of secondary batteries (1000) may be fixed by a housing (61, 62, 63, 64). The housing (61, 62, 63, 64) may include a pair of end plates (61, 62) facing the wide surfaces of the secondary batteries (1000), a side plate (63) and a bottom plate (64) connecting the pair of end plates (61, 62). The side plate (63) may support the side of the secondary battery (1000), and the bottom plate (64) may support the bottom surface of the secondary battery (1000). Additionally, the above pair of end plates (61, 62), side plate (63), and bottom plate (64) can be connected by a member such as a bolt (65).

[0159] The protection circuit module (30) is equipped with electronic components and protection circuits, and can be electrically connected to a connection tab (20) to be described below. The protection circuit module (30) includes a first protection circuit module (30a) and a second protection circuit module (30b) extending at different locations along the direction in which a plurality of secondary batteries (1000) are arranged. At this time, the first protection circuit module (30a) and the second protection circuit module (30b) are spaced apart at a certain distance but positioned parallel to each other and can be electrically connected to an adjacent connection tab (20). For example, the first protection circuit module (30a) is formed extending to one side of the upper portion of the plurality of secondary batteries (1000) along the direction in which the plurality of secondary batteries (1000) are arranged, and the second protection circuit module (30b) is formed extending to the other side of the upper portion of the plurality of secondary batteries (1000) along the direction in which the plurality of secondary batteries (1000) are arranged, wherein the second protection circuit module (30b) is positioned at a certain distance from the first protection circuit module (30a) with the vent (850) in between, but can be arranged parallel to the first protection circuit module (30a). In this way, the two protection circuit modules are arranged parallel to each other and spaced apart along the direction in which the plurality of secondary batteries are arranged, thereby minimizing the area of ​​the PCB (Printed Circuit Board) constituting the protection circuit module. By configuring the protection circuit module separately into two protection circuit modules, the unnecessary PCB area is minimized. Additionally, the first protection circuit module (30a) and the second protection circuit module (30b) can be connected to each other by a conductive connecting member (50). At this time, one side of the connecting member (50) is connected to the first protection circuit module (30a), and the other side is connected to the second protection circuit module (30b), thereby enabling an electrical connection between the two protection circuit modules.

[0160] The above connection can be made by any one of the following methods: soldering, resistance welding, laser welding, or projection welding.

[0161] In addition, the connecting member (50) may be, for example, an electric wire. Furthermore, the connecting member (50) may be made of a material having elasticity or flexibility. Through this connecting member (50), the voltage, temperature, and current of a plurality of secondary batteries (1000) can be checked and managed to ensure they are normal. That is, information such as voltage, current, and temperature received by the first protection circuit module from the adjacent connection tabs and information such as voltage, current, and temperature received by the second protection circuit module from the adjacent connection tabs can be integrated and managed by the protection circuit module through the connecting member.

[0162] In addition, when the secondary battery (1000) swells, the impact is absorbed by the elasticity or flexibility of the connecting member (50), thereby preventing damage to the first and second protection circuit modules (30a, 30b).

[0163] In addition, the shape and structure of the connecting member (50) are not limited to the shape shown in FIG. 16.

[0164] In this way, by providing the protection circuit module (30) as a first and second protection circuit module (30a, 30b), the area of ​​the PCB constituting the protection circuit module can be minimized, thereby enabling space to be secured inside the battery module. This improves work efficiency by making it easier to perform the fastening work connecting the connection tab (20) and the protection circuit module (30), as well as repairs when an abnormality is detected in the battery module.

[0165] The secondary battery and battery module according to the embodiment described above can be used to manufacture a battery pack.

[0166] Referring to FIGS. 17 and 18, the battery pack (3000) may include a plurality of battery modules (3200) and a housing (3100) for accommodating the plurality of battery modules (3200). For example, the housing (3100) may include first and second housings (3110, 3120) that are coupled in a direction facing each other with the plurality of battery modules (3200) interposed therebetween. The plurality of battery modules (3200) may be electrically connected to each other using a bus bar (3500), and the plurality of battery modules (3200) may be electrically connected to each other in a series / parallel or mixed series-parallel manner to obtain the required electrical output. For convenience, the illustration of components such as bus bars, cooling units, and external terminals for the electrical connection of the secondary batteries is omitted in the drawings. In some examples, the battery pack (3300) may be mounted in a vehicle. The vehicle may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. Motor vehicles may include four-wheeled vehicles or two-wheeled vehicles.

[0167] Referring to FIG. 19, the battery pack (3000) may include a battery pack cover (3010) (which may correspond to the first housing) which is part of the vehicle under body (4100) and a pack frame (3020) (which may correspond to the second housing) disposed at the bottom of the vehicle under body (4100). The battery pack cover (3010) and the pack frame (3020) may be structures formed integrally with the vehicle floor portion (4200). The vehicle under body (4100) separates the interior and exterior of the vehicle, and the pack frame (3020) may be disposed on the exterior of the vehicle.

[0168] Referring to FIG. 20, the vehicle (4000) may be formed by combining additional parts such as a hood (4300) at the front of the vehicle and fenders (4400) located at the front and rear of the vehicle, respectively. The vehicle (4000) includes a battery pack (3000) comprising a battery pack cover (3010) and a pack frame (3020), and the battery pack (3000) may be coupled to the vehicle (4000).

[0169] Although the present disclosure has been described above by limited embodiments and drawings, the present disclosure is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present disclosure and the equivalent scope of the claims set forth below by those skilled in the art to which the present disclosure belongs.

Claims

1. A case including a receiving portion; An electrode assembly that is housed in the above case and includes a core portion; A first current collector plate disposed on the upper part of the electrode assembly; and It includes a second current collector plate disposed at the bottom of the electrode assembly, and The first current collector plate or the second current collector plate includes a first electrolyte injection area including a first hole and a second electrolyte injection area including a second hole, and The first electrolyte injection area overlaps with the core portion, and The diameter of the first electrolyte injection region is larger than the diameter of the core portion, and The first hole above is a secondary battery disposed inside the innermost separator disposed on the side of the core part.

2. In Paragraph 1, The first current collector plate includes a first electrolyte injection area including the first hole and a second electrolyte injection area including the second hole, and The first electrolyte injection area is positioned in the central area of ​​the first current collector plate, and The second electrolyte injection area is a secondary battery disposed in the edge area of ​​the first current collector plate.

3. In Paragraph 2, The above-mentioned first hole is formed by a first opening region and a second opening region, and The first electrolyte injection area above includes a closed area, and The first opening region is positioned in the central region of the first electrolyte injection region, and The second opening region above is a secondary battery protruding from the first opening region.

4. In Paragraph 3, The first opening region is a secondary battery surrounded by the second opening region and the closed region.

5. In Paragraph 3, The outer diameter of the circle connecting the second opening area is a secondary battery disposed inside the innermost separator.

6. In Paragraph 3, A secondary battery in which the first opening region and the second opening region are integrally formed.

7. In Paragraph 3, The above closed region is a secondary battery disposed in a first electrolyte injection region other than the above first opening region and the above second opening region.

8. In Paragraph 3, The diameter of the first electrolyte injection area is 3.5 mm to 4.5 mm, and A secondary battery in which the diameter of the innermost separator is 2.7 mm to 3.4 mm.

9. In Paragraph 3, A secondary battery in which the width of the second opening region is smaller than the width of the first opening region.

10. In Paragraph 3, The sum of the areas of the first opening region and the second opening region has a first area, The above-mentioned closed area has a second area, The above second area is a secondary battery larger than the above first area.

11. In Paragraph 10, The first area is 25% to 49% of the first electrolyte injection area, and A secondary battery in which the second area is 51% to 75% of the first electrolyte injection area.

12. In Paragraph 1, The above-mentioned first hole includes a first-1 hole and a plurality of first-2 holes, and The first current collector plate comprises a first electrolyte injection area including the first-1 hole and the first-2 hole; and a second electrolyte injection area including the second hole, The first electrolyte injection area is positioned in the central area of ​​the first current collector plate, and The second electrolyte injection area is positioned in the edge area of ​​the second current collector plate, and The above 1-1 hole is formed by a first opening region and a second opening region, and The first electrolyte injection area above includes a closed area, and The first opening region is positioned in the central region of the first electrolyte injection region, and The second opening region protrudes from the first opening region, and The above first and second holes are secondary batteries disposed on the inner side of the outer diameter of the circle connecting the above second opening regions.

13. In Paragraph 12, A secondary battery in which the diameter of the first and second holes is smaller than the first opening area and the second opening area.

14. In Paragraph 1, The first current collector plate includes a first electrolyte injection area including the first hole and a second electrolyte injection area including the second hole, and The first electrolyte injection area is positioned in the central area of ​​the first current collector plate, and The second electrolyte injection area is positioned in the edge area of ​​the second current collector plate, and The above-mentioned first hole is formed by a first opening region and a second opening region, and The first electrolyte injection area above includes a closed area, and The first opening region is positioned in the central region of the first electrolyte injection region, and The second opening region is a secondary battery spaced apart from the first opening region.

15. In Paragraph 14, The second opening region is a secondary battery disposed between the outer diameter of the first opening region and the outer diameter of the innermost separator.

16. In Paragraph 14, The first opening region and the second opening region are formed with the same shape, and A secondary battery in which the size of the second opening region is smaller than the size of the first opening region.

17. In Paragraph 1, The first current collector plate includes a first electrolyte injection area including the first hole and a second electrolyte injection area including the second hole, and The first electrolyte injection area is positioned in the central area of ​​the first current collector plate, and The second electrolyte injection area is positioned in the edge area of ​​the second current collector plate, and The above-mentioned first hole is formed by a first opening region and a second opening region, and The first electrolyte injection area above includes a closed area, and The first opening region is positioned in the central region of the first electrolyte injection region, and The above closed area is formed in a mesh shape, and The second opening region is a secondary battery disposed in the mesh-shaped open region.

18. In Paragraph 2, A secondary battery further comprising a cap assembly that seals the above case.

19. In Paragraph 1, The second current collector plate includes a first electrolyte injection area including the first hole and a second electrolyte injection area including the second hole, and The first electrolyte injection area is positioned in the central area of ​​the second current collector plate, and The second electrolyte injection area is a secondary battery disposed in the edge area of ​​the second current collector plate.

20. In Paragraph 19, A secondary battery further comprising a cap plate that seals the above case.

Images