Battery, current collector plate applied thereto, battery pack including the same, and motor vehicle

Abstract

A battery according to an embodiment of the present invention includes an electrode assembly having a first electrode tab and a second electrode tab defined by an uncoated portion; a battery housing that receives the electrode assembly and is electrically connected to the second electrode tab; a cap plate configured to seal an opening of the battery housing; a current collector plate having a peripheral portion, a tab coupling portion extending inward from the peripheral portion and coupled to the first electrode tab, and a terminal coupling portion spaced apart from the tab coupling portion; and a terminal coupled to the terminal coupling portion.

Description

Technical Field

[0001] The present invention relates to a battery, a current collector plate applied thereto, a battery pack including the same, and a vehicle. More specifically, the present invention relates to a battery having a structure in which force is not concentrated on a welding site between components even when external impact or vibration is applied during the use of the battery, a current collector plate applied thereto, a battery pack including the same, and a vehicle.

[0002] This application claims priority based on Korean Patent Application Nos. 10-2021-0137001 filed on October 14, 2021, 10-2021-0178999 filed on December 14, 2021, and 10-2021-0194611 filed on December 31, 2021, and all of the contents disclosed in the specifications and drawings of the applications are incorporated herein.

Background Art

[0003] The application areas of batteries capable of repeated charging and discharging are very diverse. Among them, for example, a battery pack applied to a device such as an electric vehicle is required to have a large capacity and high output. A battery pack having a large capacity and high output includes a plurality of batteries.

[0004] In the case of a battery having large capacity and high output characteristics, in order to improve the current collection efficiency, electrode tabs are provided on the entire both sides of a jelly-roll, and current collector plates are respectively coupled to the both sides of the jelly-roll. By applying such a structure, the contact area between the electrode tab and the current collector plate can be maximized, and thereby the resistance generated at the connection site between components can be minimized.

[0005] As described above, when a battery is applied to a device such as an electric vehicle, it is frequently exposed to external impact and vibration during use, and thus damage may occur at the coupling site for electrical connection between components. Such damage to the coupling site causes product defects.

[0006] Also, not only in the case where the coupling part for electrical connection is damaged and the electrical connection is completely severed, but also when the welding part is partially damaged and the coupling area between components is reduced, problems such as excessive heat generation due to increased resistance and internal short circuit generation due to component deformation may occur.

[0007] Therefore, it is necessary to develop a battery having a structure in which force is not concentrated on the coupling part between components even when external impact and / or vibration is applied during use.

[0008] Conventionally, a flat current collector plate having flexibility to be deformed in the axial direction of the battery has been disclosed. However, each time the flat current collector plate is deformed in the axial direction, torsional stress is applied to the joint (welding) part of the current collector plate, which may cause the dropout of the current collector contact.

Summary of the Invention

Problems to be Solved by the Invention

[0009] The present invention has been made in view of the above-described problems, and even when external impact and / or vibration is applied during the use of the battery, the impact and / or vibration is not concentrated on a specific part but is dispersed, thereby preventing the occurrence of damage at the coupling part between components.

[0010] Another object of the present invention is to provide a current collector plate having flexibility in the axial direction and the radial direction while maintaining a flat state and not generating torsional stress at the contact even when deformed.

[0011] Still another object of the present invention is to ensure the safety in the use of the battery by quickly interrupting the current when an overcurrent occurs due to a short circuit or the like by having the current collector plate itself perform a current interruption function without further providing a current interruption member.

[0012] The technical problem of the present invention is not limited to the problems described above, and other objects and advantages of the present invention not mentioned can be understood from the following description and will be more clearly understood from the embodiments of the present invention. Also, the objects and advantages of the present invention can be realized by the means and their combinations shown in the claims.

Means for Solving the Problem

[0013] The present invention provides a current collector plate that electrically connects the first electrode tab and the terminal between the first electrode tab of the electrode assembly and the terminal exposed to the outside.

[0014] The current collector plate includes a peripheral portion extending in the circumferential direction, a tab coupling portion extending from the peripheral portion toward the center and coupled to the first electrode tab, and a terminal coupling portion disposed closer to the center than the peripheral portion and connected to the tab coupling portion through the peripheral portion while avoiding the tab coupling portion.

[0015] Among the terminal coupling portion, the peripheral portion, and the tab coupling portion, the peripheral portion may be disposed farthest from the center, and the terminal coupling portion may be disposed closest to the center.

[0016] The center of the terminal coupling portion and the center of the peripheral portion may substantially coincide.

[0017] The peripheral portion may be in the form of a rim with a hollow center.

[0018] The peripheral portion may be a flat ring shape that is substantially circular.

[0019] A plurality of the tab coupling portions may be arranged along the circumferential direction of the peripheral portion.

[0020] The extension lengths of the plurality of tab coupling portions may correspond to each other.

[0021] The plurality of tab coupling portions may be arranged at equal intervals along the circumferential direction of the peripheral portion.

[0022] The tab connection part may extend from the inner circumference of the peripheral part toward the centripetal side.

[0023] Based on a virtual line that linearly connects two adjacent tab connection parts and the connection part of the peripheral part in the circumferential direction, the part of the peripheral part provided between two adjacent tab connection parts may be arranged further on the centrifugal side than the virtual line.

[0024] The terminal connection part may be connected to the part of the peripheral part provided between two adjacent tab connection parts in the circumferential direction.

[0025] The terminal connection part is arranged at or near the center of the centripetal region rather than the peripheral part, and the peripheral part and the terminal connection part may be connected by a connection part.

[0026] The connection part may extend further radially outside than the tab connection part.

[0027] The terminal connection part may be arranged so as to be surrounded by a plurality of the tab connection parts.

[0028] A plurality of the tab connection parts are separated from the terminal connection part in the radial direction and may be arranged radially around the terminal connection part.

[0029] The connection part may extend linearly to connect the terminal connection part and the peripheral part.

[0030] The connection part may be in a linear form passing through the center of the current collector plate.

[0031] The connection part may extend radially from the terminal connection part and be connected to the peripheral part.

[0032] The connection part may extend substantially radially from the center of the terminal connection part and be connected to the peripheral part.

[0033] A plurality of the connection parts may be provided and arranged at equal intervals along the outer circumference of the terminal connection part.

[0034] The plurality of the connecting portions may be arranged at equal intervals along the circumferential direction of the peripheral portion.

[0035] The connecting portion may be located between a pair of tab coupling portions adjacent in the circumferential direction.

[0036] The distance from the connecting portion to one of the pair of tab coupling portions along the circumferential direction may correspond to the distance from the connecting portion to the other of the pair of tab coupling portions along the circumferential direction.

[0037] The current-carrying path from the terminal coupling portion to the tab coupling portion may be in the order of the terminal coupling portion, the connecting portion, the peripheral portion, and the tab coupling portion.

[0038] At least a partial section along the extending direction of the connecting portion may be formed to have a width narrower than that of the tab coupling portion.

[0039] The connecting portion may include a tapered portion whose width gradually narrows in a direction from the inner circumferential surface of the peripheral portion toward the terminal coupling portion.

[0040] The connecting portion may include a notching portion where the cross-sectional area is locally reduced in its extending direction.

[0041] The notching portion may be located closer to the peripheral portion than the terminal coupling portion.

[0042] The portion of the tab coupling portion facing the terminal coupling portion may be in a tapered shape toward the terminal coupling portion.

[0043] The current collector plate may have a radially symmetric structure.

[0044] The current collector plate may have a radially symmetric structure by rotation of 90°, 120°, or 180°.

[0045] The current collector plate may be used for a battery.

[0046] The battery in which the current collector plate is used may include a battery housing that houses an electrode assembly.

[0047] The electrode assembly is an electrode assembly that defines a core and an outer peripheral surface by winding a first electrode, a second electrode, and a separation membrane interposed between the first electrode and the second electrode around a winding axis. The first electrode and the second electrode each include a first electrode tab made of a first plain portion and a second electrode tab made of a second plain portion at long side ends along the winding direction, and the first electrode tab and the second electrode tab may protrude outside the separation membrane in opposite directions in the winding axis direction.

[0048] The battery may be insulatingly attached to the battery housing and may include terminals exposed to the outside.

[0049] The current collector plate may include a peripheral portion that defines a space inside, a tab coupling portion that extends from the peripheral portion toward the centripetal side and is coupled to the first electrode tab, a terminal coupling portion disposed on the centripetal side of the peripheral portion, and a connecting portion that connects the terminal coupling portion and the peripheral portion while avoiding the tab coupling portion.

[0050] The first electrode tab may be coupled to the tab coupling portion of the current collector plate, and the terminal may be coupled to the terminal coupling portion of the current collector plate.

[0051] The first electrode tab may include a plurality of divided sections separated by a cutting groove along the winding direction and protruding outside the separation membrane along the winding axis direction.

[0052] The plurality of divided sections may be aligned while overlapping along the radial direction of the electrode assembly to constitute a plurality of divided section alignment portions spaced apart in the circumferential direction.

[0053] The divided sections included in each divided section alignment portion may be bent along the radial direction to form a bent surface region.

[0054] The tab joint portion of the current collector plate is coupled to the bent surface region, and the connecting portion may be disposed between the segmented alignment portions spaced apart in the circumferential direction.

[0055] The connecting portion includes a notching portion whose cross-sectional area decreases in its extending direction, and the notching portion may be spaced apart from the end surface of the electrode assembly exposed between the segmented alignment portions spaced apart in the circumferential direction.

[0056] The end surface of the electrode assembly exposed between the segmented alignment portions spaced apart in the circumferential direction may be an electrolyte impregnated portion.

[0057] In the electrolyte impregnated portion, the end portions of the first electrode and the second electrode in the winding axis direction may be exposed from between the separation membranes of the adjacent winding turns.

[0058] One axial side of the battery housing may form a closed portion that is closed, and the other side may form an open portion that is open.

[0059] An electrode assembly including a first electrode tab and a second electrode tab may be inserted through the open portion.

[0060] The first electrode tab and the second electrode tab of the electrode assembly may be provided on one axial side and the other axial side, respectively.

[0061] With the electrode assembly housed in the battery housing, the first electrode tab may face the closed portion, and the second electrode tab may face the open portion.

[0062] A terminal may be provided on the closed portion.

[0063] The terminal may penetrate the closed portion.

[0064] The second electrode tab may be electrically connected to the battery housing.

[0065] The terminal connection portion of the current collector plate can be disposed at a position corresponding to a hole formed in the winding center portion of the electrode assembly.

[0066] The end portion of the first electrode tab can be bent in the radial direction.

[0067] The first electrode tab can be bent in the centripetal direction or the centrifugal direction.

[0068] The tab connection portion of the current collector plate can be coupled to the surface of the bent first electrode tab.

[0069] The connecting portion can face and be adjacent to the surface of the bent first electrode tab.

[0070] The peripheral portion can face and contact the surface of the bent first electrode tab.

[0071] The open portion of the battery housing can be sealed by a cap plate.

[0072] The cap plate may not be electrically connected to the first electrode tab and the second electrode tab of the electrode assembly. Thus, the cap plate has no polarity.

[0073] An insulator can be interposed between the closing portion and the current collector plate.

[0074] The terminal can pass through the insulator and be coupled to the terminal connection portion of the current collector plate.

[0075] A plurality of the batteries can be housed in a pack housing to form a battery pack.

[0076] The battery pack can be mounted on an automobile.

Advantages of the Invention

[0077] According to the present invention, even if external impact and / or vibration are applied during the use of the battery, the impact and / or vibration are dispersed without being concentrated on specific parts, thereby preventing the occurrence of breakage at the joint parts between components.

[0078] Moreover, according to the present invention, even without further providing a current interruption member, the current collection plate itself can perform a current interruption function, whereby when an overcurrent occurs due to a short circuit or the like, the current is quickly interrupted to ensure the safety in the use of the battery.

[0079] Also, according to the present invention, the connection path from the terminal connection part to the tab connection part in the current collection plate is in a form that detours through a connection part further extended radially outside the tab connection part and a peripheral part extended in the circumferential direction and then returns to the tab connection part extended radially inside again. Therefore, the shape of the current collection plate not only entirely covers the electrode tab part of the electrode assembly, but also can flexibly respond to impact and vibration, and by suppressing the phenomenon that the current collection plate floats in the vertical direction, the current collection plate can maintain a posture of pressing the electrode tab of the electrode assembly, and the phenomenon that the electrode tab is deformed due to excessive deformation of the current collection plate can be prevented.

[0080] Further, according to the present invention, even if the terminal connection part and the tab connection part receive an external force or vibration relatively in the axial direction or the radial direction, since the connection part extends linearly and radially, torsional stress does not act on the joint part between the terminal connection part and the tab connection part and the joint part does not come apart.

[0081] The technical effects achieved by the present invention are not limited to the above-described effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the invention to be described later.

[0082] Together with the above-described effects, the specific effects of the present invention will be described later together with the specific embodiments for carrying out the invention.

Brief Description of the Drawings

[0083]

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Figure 8

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Figure 10

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Figure 12

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Figure 15

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Figure 17

Figure 18a

Figure 18b

Figure 19a

Figure 19b

Figure 20

Figure 21

Mode for Carrying Out the Invention

[0084] The object, features, and advantages of the present invention will be described in detail below with reference to the accompanying drawings, so that those having ordinary knowledge in the technical field to which the present invention pertains can easily implement the technical idea of the present invention. In the description of the present invention, when it is determined that a specific description of related known technologies may obscure the gist of the present invention, the detailed description thereof will be omitted. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals mean the same or similar components.

[0085] Terms such as first and second are used to indicate various components, but these components are not limited by such terms. These terms are merely used to distinguish one component from another, and unless otherwise specified, the first component can also be the second component.

[0086] Throughout the specification, unless otherwise specified, each component may be singular or plural.

[0087] Hereinafter, when any configuration is arranged "above (or below)" a component or "on (or under)" a component, it means not only that any configuration is arranged in contact with the upper surface (or lower surface) of the component, but also that other configurations may be interposed between the component and any configuration arranged above (or below) the component.

[0088] Also, when a certain component is "connected", "coupled" or "joined" to another component, it includes not only the case where the components are directly connected or joined to each other, but also the case where other components are "interposed" between the components, or the case where each component is "connected", "coupled" or "joined" through other components.

[0089] Also, the singular expressions used in this specification include plural expressions unless the context clearly indicates otherwise. In this application, terms such as "configured" or "comprising" are not construed as necessarily including all of the many components or many steps described in the specification, and some of the components or steps may not be included, and additional components or steps may further be included.

[0090] Throughout the specification, "A and / or B" means A, B, or A and B unless otherwise specified, and "C to D" means C or more and D or less unless otherwise specified.

[0091] Hereinafter, in the description of the embodiments, the height direction in which the battery is extended is referred to as the height direction or the axial direction (Z-axis), and the direction surrounding the axial direction is referred to as the circumferential direction or the outer circumferential direction. Here, in the height direction of the battery, the direction in which the opening portion is formed is defined as the lower direction, and the direction in which the closing portion is formed is defined as the upper direction.

[0092] Also, the direction extending radially from the center of the battery is referred to as the radial direction or the radial direction (X, Y), the direction toward the outside in the radial direction is the centrifugal direction, and the direction toward the inside in the radial direction is the centripetal direction.

[0093] Referring to FIGS. 1 to 4, the battery 1 according to the present invention houses the electrode assembly 10 inside a cylindrical battery housing 20.

[0094] The upper part (one axial end) of the battery housing 20 constitutes a closed part, and the lower part (the other axial end) constitutes an open part.

[0095] A terminal 50 is provided at the center of the closed part.

[0096] The open part is sealed by a cap plate 30.

[0097] The electrode assembly 10 includes a first electrode tab 11 and a second electrode tab 12.

[0098] The first electrode tab 11 is electrically connected to the terminal 50, and the second electrode tab 12 is electrically connected to the battery housing 20.

[0099] The terminal 50 and the battery housing 20 are insulated from each other.

[0100] The present invention provides a current collector plate 40 that electrically connects the first electrode tab 11 of the electrode assembly 10 and the terminal 50.

[0101] The current collector plate 40 can be disposed between the closed part of the battery housing 20 and the electrode assembly 10.

[0102] Referring to FIGS. 5 to 10, the current collector plate 40 includes a peripheral portion 41 that extends in the circumferential direction and defines a space inside, a tab coupling portion 42 that extends from the peripheral portion 41 toward the center and is coupled to the first electrode tab 11, and a terminal coupling portion 43 that is disposed closer to the center than the peripheral portion 41, is spaced apart from the tab coupling portion 42, and is connected to the tab coupling portion 42 through the peripheral portion 41.

[0103] Among the terminal coupling portion 43, the peripheral portion 41, and the tab coupling portion 42, the peripheral portion 41 can be disposed on the outermost side in the centrifugal direction, and the terminal coupling portion 43 can be disposed on the innermost side in the centripetal direction.

[0104] The peripheral portion 41 can be in the form of a rim with a hollow center.

[0105] The peripheral portion 41 can be a flat plate ring substantially circular in shape.

[0106] A plurality of the tab coupling portions 42 can be arranged along the circumferential direction of the peripheral portion 41.

[0107] The extension lengths of each of the plurality of tab coupling portions 42 can correspond to each other.

[0108] The plurality of tab coupling portions 42 can be arranged at equal intervals along the circumferential direction of the peripheral portion 41.

[0109] The tab coupling portion 42 can extend from the inner circumference of the peripheral portion 41 toward the center.

[0110] The portion of the tab coupling portion 42 facing the terminal coupling portion 43 can be in a tapered shape toward the terminal coupling portion 43. The tapered shape increases the opening area of the current collector plate 40 by reducing the unnecessary area of the tab coupling portion 42.

[0111] Based on a virtual line (the dotted line in Fig. 8) that linearly connects two adjacent tab coupling portions 42 and the connecting portion of the peripheral edge portion 41 in the circumferential direction, the portion of the peripheral edge portion 41 provided between two adjacent tab coupling portions 42 (the two-dot chain line portion in Fig. 8) can be arranged further on the centrifugal side than the virtual line (the dotted line in Fig. 8).

[0112] The terminal coupling portion 43 can be connected to a portion of the peripheral edge portion 41 provided between two adjacent tab coupling portions 42 in the circumferential direction.

[0113] The terminal coupling portion 43 is arranged at or near the center of the centripetal region rather than the peripheral edge portion 41, and the peripheral edge portion 41 and the terminal coupling portion 43 can be connected by a connecting portion 44.

[0114] The connecting portion 44 can be further extended radially outward than a virtual line (the dotted line in Fig. 8) that linearly connects two adjacent tab coupling portions 42 and the connecting portion of the peripheral edge portion 41 in the circumferential direction (the one-dot chain line in Fig. 8).

[0115] The terminal coupling portion 43 can be arranged so as to be surrounded by a plurality of the tab coupling portions 42.

[0116] A plurality of the tab coupling portions 42 are radially spaced apart from the terminal coupling portion 43 and can be arranged radially around the terminal coupling portion 43.

[0117] The connecting portion 44 can be linearly extended to connect the terminal coupling portion 43 and the peripheral edge portion 41.

[0118] The connecting portion 44 can be in a linear form passing through the center of the current collector plate 40.

[0119] The connecting portion 44 can be extended radially from the terminal coupling portion 43 to be connected to the peripheral edge portion 41.

[0120] The connecting portion 44 can be substantially extended radially from the center of the terminal coupling portion 43 to be connected to the peripheral edge portion 41.

[0121] A plurality of the connecting portions 44 may be provided and arranged at equal intervals along the outer circumference of the terminal connecting portion 43.

[0122] The plurality of connecting portions 44 may be arranged at equal intervals along the circumferential direction of the peripheral portion 41.

[0123] The connecting portion 44 may be located between a pair of adjacent tab connecting portions 42 in the circumferential direction.

[0124] The connecting portion 44 extends in the space between the peripheral portion 41 and the terminal connecting portion 43 while avoiding the tab connecting portion 42, and electrically connects the peripheral portion 41 and the terminal connecting portion 43.

[0125] The distance from the connecting portion 44 along the circumferential direction to one of the pair of tab connecting portions 42 may correspond to the distance from the connecting portion 44 along the circumferential direction to the other of the pair of tab connecting portions 42.

[0126] The current collecting plate 40 may have a radially symmetric structure. The radially symmetric structure means a symmetric structure in which the shape of the object coincides when the object to be measured for symmetry is rotated by a predetermined angle. Desirably, the current collecting plate 40 may have a radially symmetric structure by rotation of 90°, 120° or 180°. In one example, the structure of the current collecting plate 40 may coincide when rotated by 90°. However, the present invention is not limited by the rotation angle of the radially symmetric structure.

[0127] The current conduction path from the terminal connecting portion 43 to the tab connecting portion 42 may be in the order of the terminal connecting portion 43, the connecting portion 44, the peripheral portion 41 and the tab connecting portion 42.

[0128] At least a partial section along the extending direction of the connecting portion 44 may be formed to have a width even narrower than that of the tab connecting portion 42.

[0129] If the terminal coupling part 43 receives a force in the radial direction and / or the axial direction relative to the tab coupling part 42, the peripheral part 41 and / or the connecting part 44 between two adjacent tab coupling parts 42 can absorb it while being deformed. At this time, torsional stress does not occur at the coupling part between the terminal coupling part 43 and the tab coupling part 42.

[0130] The connecting part 44 may include a tapered part 44a whose width gradually narrows in the direction from the inner peripheral surface of the peripheral part 41 toward the terminal coupling part 43.

[0131] Referring to FIGS. 9 and 10, the connecting part 44 may include a notching part N whose cross-sectional area is locally reduced along its extending direction.

[0132] The notching part N may be located closer to the peripheral part 41 than the terminal coupling part 43.

[0133] Referring further to FIGS. 1 to 4, the current collector plate 40 can be used for the battery 1.

[0134] The battery 1 in which the current collector plate 40 is used may include a battery housing 20 that houses the electrode assembly 10.

[0135] One axial side of the battery housing 20 may form a closed part that is blocked, and the other side may form an open part that is open.

[0136] The electrode assembly 10 including the first electrode tab 11 and the second electrode tab 12 may be inserted through the open part.

[0137] The first electrode tab 11 and the second electrode tab 12 of the electrode assembly 10 may be provided on one axial side and the other axial side, respectively.

[0138] In a state where the electrode assembly 10 is housed in the battery housing 20, the first electrode tab 11 may face the closed part, and the second electrode tab 12 may face the open part.

[0139] A terminal 50 may be provided in the closing part.

[0140] The terminal 50 may penetrate the closing part.

[0141] The first electrode tab 11 may be electrically connected to the terminal 50.

[0142] The first electrode tab 11 and the terminal 50 may be electrically connected through the current collector plate 40.

[0143] The first electrode tab 11 may be coupled to the tab coupling part 42 of the current collector plate 40, and the terminal 50 may be coupled to the terminal coupling part 43 of the current collector plate 40.

[0144] The second electrode tab 12 may be electrically connected to the battery housing 20.

[0145] The terminal coupling part 43 of the current collector plate 40 may be disposed at a position corresponding to a hole formed in the winding center part C of the electrode assembly 10.

[0146] The end of the first electrode tab 11 may be bent in the radial direction as shown in FIG. 4.

[0147] The first electrode tab 11 may be bent in the centripetal direction or the centrifugal direction.

[0148] The tab coupling part 42 of the current collector plate 40 may be coupled to the surface of the bent first electrode tab 11.

[0149] The connecting part 44 may face and contact the surface of the bent first electrode tab 11.

[0150] The peripheral part 41 may face and contact the surface of the bent first electrode tab 11.

[0151] The open part of the battery housing 20 may be sealed by the cap plate 30.

[0152] The cap plate 30 may not be electrically connected to the first electrode tab 11 and the second electrode tab 12 of the electrode assembly 10. As a result, the cap plate 30 has no polarity.

[0153] An insulator 60 may be interposed between the closing portion and the current collector plate 40.

[0154] The terminal 50 may pass through the insulator 60 and be coupled to the terminal coupling portion 43 of the current collector plate 40.

[0155] A plurality of the batteries 1 may be housed in a pack housing 2 as shown in FIG. 19 to form a battery pack 3.

[0156] Also, the battery pack 3 may be mounted on an automobile 5 as shown in FIG. 20.

[0157] Referring further to FIGS. 1 and 2, a battery 1 according to an embodiment of the present invention includes an electrode assembly 10, a battery housing 20, a cap plate 30, a current collector plate (first current collector plate) 40, and a terminal 50. In addition to the above-described components, the battery 1 may further include a sealing gasket G1 and / or an insulating gasket G2 and / or an insulator 60 and / or a second current collector plate 70.

[0158] The electrode assembly 10 includes a first electrode having a first polarity, a second electrode having a second polarity, and a separator interposed between the first electrode and the second electrode. The first electrode is a positive electrode or a negative electrode, and the second electrode corresponds to an electrode having a polarity opposite to that of the first electrode.

[0159] The electrode assembly 10 may have, for example, a jelly roll structure. That is, the electrode assembly 10 may be manufactured by winding a laminate formed by sequentially laminating at least once a first electrode, a separator, and a second electrode around a winding center portion C. In this case, an additional separator may be provided on the outer peripheral surface of the electrode assembly 10 for insulation from the battery housing 20.

[0160] The first electrode includes a first current collector and a first electrode active material layer coated on one or both surfaces of the first current collector. There is a plain portion on one end side in the width direction (Z-axis direction) of the first current collector where the first electrode active material is not coated. The plain portion functions as the first electrode tab 11. The first electrode tab 11 is provided at the upper part in the height direction (Z-axis direction) of the electrode assembly 10 housed in the battery housing 20.

[0161] The second electrode includes a second current collector and a second electrode active material layer coated on one or both surfaces of the second current collector. There is a plain portion on the other end side in the width direction (Z-axis direction) of the second current collector where the second electrode active material is not coated. The plain portion functions as the second electrode tab 12. The second electrode tab 12 is provided at the lower part in the height direction (Z-axis direction) of the electrode assembly 10 housed in the battery housing 20.

[0162] That is, the first electrode tab 11 and the second electrode tab 12 extend in opposite directions along the width direction of the electrode assembly 10, that is, the height direction (Z-axis direction) of the battery 1. The first electrode tab 11 extends toward the closed portion of the battery housing 20, and the second electrode tab 12 extends toward the open portion of the battery housing 20.

[0163] In the present invention, the positive electrode active material coated on the positive electrode plate and the negative electrode active material coated on the negative electrode plate can be used without limitation as long as they are active materials known in the art.

[0164] In one example, the positive electrode active material has the general chemical formula A(A x M y )O 2+z(A contains at least one element of Li, Na, and K; M contains at least one element selected from Ni, Co, Mn, Ca, Mg, Al, Ti, Si, Fe, Mo, V, Zr, Zn, Cu, Al, Mo, Sc, Zr, Ru, and Cr; x≧0, 1≦x + y≦2, -0.1≦z≦2; the stoichiometric coefficients x, y, and z are selected so that the compound maintains electrical neutrality) and may contain an alkali metal compound represented by.

[0165] As another example, the positive electrode active material is an alkali metal compound xLiM disclosed in U.S. Patent No. 6,677,082, U.S. Patent No. 6,680,143, etc. 1 O2-(1 - x)Li2M 2 O3(M 1 (M contains at least one element having an average oxidation state of 3; M 2 (M contains at least one element having an average oxidation state of 4; 0≦x≦1).

[0166] As yet another example, the positive electrode active material has the general chemical formula Li a M 1 x Fe 1-x M 2 y P 1-y M 3 z O 4-z (M 1 (M contains at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, and Al; M 2 (M contains at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, Al, As, Sb, Si, Ge, V, and S; M 3 (M contains a halogen group element selectively containing F; 0 < a≦2, 0≦x≦1, 0≦y < 1, 0≦z < 1; the stoichiometric coefficients a, x, y, and z are selected so that the compound maintains electrical neutrality), or it may be a lithium metal phosphate represented by Li3M2(PO4)3 [M contains at least one element selected from Ti, Si, Mn, Fe, Co, V, Cr, Mo, Ni, Al, Mg, and Al].

[0167] Desirably, the positive electrode active material may include primary particles and / or secondary particles formed by aggregation of the primary particles.

[0168] In one example, as the negative electrode active material, a carbon material, a lithium metal or a lithium metal compound, silicon or a silicon compound, tin or a tin compound, etc. can be used. Metal oxides such as TiO2 and SnO2 with a potential of less than 2V can also be used as the negative electrode active material. As the carbon material, both low-crystalline carbon and high-crystalline carbon can be used.

[0169] As the separator, a porous polymer film, for example, a porous polymer film made of a polyolefin-based polymer such as a polyethylene homopolymer, a polypropylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, an ethylene / methacrylate copolymer, etc., can be used alone or by laminating these. As another example, the separator can use a normal porous non-woven fabric, for example, a non-woven fabric made of high-melting glass fibers, polyethylene terephthalate fibers, etc.

[0170] At least one surface of the separator may include a coating layer of inorganic particles. Also, the separator itself may consist of a coating layer of inorganic particles. The particles constituting the coating layer may have a structure in which they are bonded to a binder so that an interstitial volume exists between adjacent particles.

[0171] The inorganic particles may be made of an inorganic material having a dielectric constant of 5 or more. As a non-limiting example, the inorganic particles are Pb(Zr,Ti)O3 (PZT), Pb 1-x La x Zr 1-y Ti y O3 (PLZT), PB(Mg3Nb 2 / 3)It may contain at least one substance selected from the group consisting of O3-PbTiO3 (PMN-PT), BaTiO3, hafnia (HfO2), SrTiO3, TiO2, Al2O3, ZrO2, SnO2, CeO2, MgO, CaO, ZnO, and Y2O3.

[0172] The electrolyte may be a salt having a structure such as A + B - . Here, A + contains ions consisting of alkali metal cations such as Li + , Na + , K + or combinations thereof. And B - is F - , Cl - , Br - , I - , NO3 - , N(CN)2 - , BF4 - , ClO4 - , AlO4 - , AlCl4 - , PF6 - , SbF6 - , AsF6 - , BF2C2O4 - , BC4O8 - , (CF3)2PF4 - , (CF3)3PF3 - , (CF3)4PF2 - , (CF3)5PF - , (CF3)6P - , CF3SO3 - , C4F9SO3 - , CF3CF2SO3 - , (CF3SO2)2N - , (FSO2)2N - , CF3CF2(CF3)2CO - , (CF3SO2)2CH - , (SF5)3C - , (CF3SO2)3C - , CF3(CF2)7SO3 - , CF3CO2 - , CH3CO2 - , SCN -and (CF3CF2SO2)2N - comprises any one or more anions selected from the group consisting of

[0173] Also, the electrolyte can be used by dissolving it in an organic solvent. Examples of the organic solvent include propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, tetrahydrofuran, N-methyl-2-pyrrolidone (NMP), ethyl methyl carbonate (EMC), γ-butyrolactone, or a mixture thereof.

[0174] The battery housing 20 is a substantially cylindrical container having an opening formed at the bottom, and is made of a material having conductivity such as metal. The material of the battery housing 20 can be, for example, aluminum. An opening is formed at the lower end in the height direction of the battery housing 20, and a closing portion is formed at the upper end. The battery housing 20 houses the electrode assembly 10 through the opening formed at the bottom, and also houses the electrolyte together.

[0175] The battery housing 20 is electrically connected to the electrode assembly 10. The battery housing 20 is electrically connected to, for example, the second electrode tab 12 of the electrode assembly 10. Thereby, the battery housing 20 can have the same polarity as the second electrode tab 12.

[0176] Referring to FIGS. 2 and 11, the battery housing 20 may include a beading portion 21 and a crimping portion 22 formed at its lower end. The beading portion 21 is located below the electrode assembly 10. The beading portion 21 is formed by pushing in the circumferential direction around the outer peripheral surface of the battery housing 20. The beading portion 21 can function as a support portion on which the cap plate 30 is placed, so that the electrode assembly 10 having a size substantially corresponding to the width of the battery housing 20 does not come out of the open portion formed at the lower end of the battery housing 20.

[0177] The crimping portion 22 is formed below the beading portion 21. The crimping portion 22 has a form that extends and is bent so as to wrap the outer peripheral surface of the cap plate 30 disposed below the beading portion 21 and a part of the lower surface of the cap plate 30.

[0178] However, the present invention does not exclude the case where the battery housing 20 does not include such a beading portion 21 and / or crimping portion 22. In the present invention, when the battery housing 20 does not include the beading portion 21 and / or crimping portion 22, the fixing of the electrode assembly 10 and / or the fixing of the cap plate 30 and / or the sealing of the battery housing 20 can be realized, for example, by additional application of a component that can function as a stopper for the electrode assembly 10 and / or additional application of a structure on which the cap plate 30 can be placed and / or welding between the battery housing 20 and the cap plate 30.

[0179] The closed end of the battery housing 20, i.e., the region forming the upper surface, may have a thickness of about 0.5 mm to 1.0 mm, more preferably about 0.6 mm to 0.8 mm. The side wall portion forming the outer peripheral surface of the battery housing 20 may have a thickness of about 0.3 mm to 0.8 mm, more preferably about 0.40 mm to 0.60 mm. According to an embodiment of the present invention, a plating layer may be formed on the battery housing 20. In this case, the plating layer may contain, for example, nickel (Ni). The thickness of the plating layer may be about 1.5 μm to 6.0 μm.

[0180] The thinner the battery housing 20 is, the larger the internal space becomes, thereby improving the energy density and enabling the manufacture of the battery 1 with a large capacity. On the other hand, the thicker the battery housing 20 is, the less likely there is a chain propagation of flames to adjacent batteries in an explosion test, which is advantageous in terms of safety.

[0181] The thinner the plating layer is, the more vulnerable it is to corrosion. The thicker the plating layer is, the more difficult the manufacturing process becomes or the higher the possibility of plating peeling. Considering all such conditions, it is necessary to set the optimal thickness of the battery housing 20 and the optimal thickness of the plating layer. Furthermore, considering all such conditions, it is necessary to control the thickness of the closed portion and the side wall portion of the battery housing 20 respectively.

[0182] Referring to FIGS. 2 and 11, the cap plate 30 may be made of, for example, a metal material to ensure rigidity. The cap plate 30 seals the open portion formed at the lower end of the battery housing 20. That is, the cap plate 30 constitutes the lower surface of the battery 1. In the battery 1 of the present invention, the cap plate 30 has no polarity even when it is made of a conductive metal material. The fact that the cap plate 30 has no polarity means that the cap plate 30 is electrically insulated from the battery housing 20 and the terminal 50. Thus, the cap plate 30 does not necessarily need to have a polarity, and its material does not necessarily need to be a conductive metal.

[0183] When the battery housing 20 of the present invention includes a beading portion, the cap plate 30 can be placed on the beading portion 21 formed on the battery housing 20. Also, when the battery housing 20 of the present invention includes a crimping portion 22, the cap plate 30 is fixed by the crimping portion 22. A sealing gasket G1 may be interposed between the cap plate 30 and the crimping portion 22 of the battery housing 20 to ensure the airtightness of the battery housing 20. On the other hand, as described above, the battery housing 20 of the present invention may not include the beading portion 21 and / or the crimping portion 22. In this case, the sealing gasket G1 may be interposed between a fixing structure provided on the open portion side of the battery housing 20 and the cap plate 30 to ensure the airtightness of the battery housing 20.

[0184] Referring to FIGS. 11 and 12, the cap plate 30 may further include a venting portion 31 to prevent the internal pressure from increasing beyond a preset value due to the gas generated inside the battery housing 20. The venting portion 31 corresponds to a region of the cap plate 30 that is thinner than the peripheral region. The venting portion 31 is structurally weaker than the peripheral region. Therefore, if an abnormality occurs in the battery 1 and the internal pressure of the battery housing 20 increases above a certain level, the venting portion 31 breaks and the gas generated inside the battery housing 20 is discharged. The venting portion 31 can be formed, for example, by notching on one or both surfaces of the cap plate 30 to partially reduce the thickness of the battery housing 20.

[0185] According to one embodiment of the present invention, since the battery 1 has a structure in which all the positive and negative terminals are present at the upper part as described later, the upper structure is more complex than the lower structure. Therefore, in order to smoothly discharge the gas generated inside the battery housing 20, a venting portion 31 may be formed on the cap plate 30 constituting the lower surface of the battery 1. As shown in FIG. 11, it is desirable that the lower end portion of the cap plate 30 is disposed above the lower end portion of the battery housing 20. In this case, even if the lower end portion of the battery housing 20 contacts the ground or the bottom surface of the housing for module or pack configuration, the cap plate 30 does not contact the ground or the bottom surface of the housing for module or pack configuration. Therefore, it is possible to prevent a phenomenon in which the pressure required for breaking the venting portion 31 changes from the design value due to the weight of the battery 1, thereby ensuring the breakage smoothness of the venting portion 31.

[0186] On the other hand, when the venting portion 31 has a closed loop form as shown in FIGS. 11 and 12, it is more advantageous in terms of ease of breakage that the distance from the central portion of the cap plate 30 to the venting portion 31 is farther. This is because when the same venting pressure acts, the farther the distance from the central portion of the cap plate 30 to the venting portion 31, the greater the force acting on the venting portion 31 and the easier it is to break. Also, in terms of the smoothness of discharging the venting gas, it is more advantageous that the distance from the central portion of the cap plate 30 to the venting portion 31 is farther. From such a viewpoint, it is advantageous that the venting portion 31 is formed along the periphery of a substantially flat region protruding downward (downward with reference to FIG. 11) from the peripheral region of the cap plate 30.

[0187] FIG. 12 shows a case where the venting portion 31 is continuously formed while drawing a substantially circle on the cap plate 30, but the present invention is not limited thereto. The venting portion 31 may be discontinuously formed while drawing a substantially circle on the cap plate 30, or may be formed in a substantially linear form or other forms.

[0188] Referring to FIGS. 2 to 4, the current collector plate (first current collector plate) 40 is coupled to the upper part of the electrode assembly 10. The current collector plate 40 is made of a conductive metal material and is connected to the first electrode tab 11.

[0189] Referring to FIG. 4, the current collector plate 40 can be coupled to a bonding surface formed by bending the end of the first electrode tab 11 in a direction parallel to the current collector plate 40. The bending direction of the first electrode tab 11 can be, for example, a direction toward the winding center C of the electrode assembly 10. When the first electrode tab 11 has such a bent form, the space occupied by the first electrode tab 11 can be reduced to improve the energy density. Further, an increase in the bonding area between the first electrode tab 11 and the current collector plate 40 can achieve the effects of improving the bonding force and reducing the resistance.

[0190] Referring to FIGS. 5 to 8 together with FIGS. 2 to 4, the current collector plate 40 includes a peripheral portion 41, a tab coupling portion 42, and a terminal coupling portion 43. The peripheral portion 41 can be in a substantially rim form with a space S formed in the center. Only the case where the peripheral portion 41 is in a substantially circular rim form is shown in the drawings, but the present invention is not limited thereto. The peripheral portion 41 may be in a substantially square rim form or other forms different from the illustration.

[0191] The peripheral portion 41 can be the outermost portion in the radial direction. In the embodiment, it is exemplified that the peripheral portion 41 is in a single closed loop form that is not cut along the circumferential direction. Since this is a structure that supports the rigidity of the current collector plate 40 as a whole, it can firmly support the welding portions of the tab coupling portion 42 and the terminal coupling portion 43 described later so as not to receive a shearing force (particularly, a shearing force acting in a direction parallel to the plane including the current collector plate).

[0192] However, the peripheral portion 41 does not necessarily have to be in a closed loop form, and it is of course possible that it is cut into one or two or more pieces and still forms a closed loop form as a whole.

[0193] The tab connection part 42 extends inward from the peripheral part 41 and is connected to the first electrode tab 11. The terminal connection part 43 is located inside the peripheral part 41 at a distance from the tab connection part 42. The terminal connection part 43 can be connected to a terminal 50, which will be described later, by welding. The terminal connection part 43 can be located, for example, at the center of the inner space of the peripheral part 41. The terminal connection part 43 can be arranged at a position corresponding to a hole formed in the winding center part C of the electrode assembly 10.

[0194] The tab connection part 42 and the terminal connection part 43 are not directly connected but are arranged separately and are electrically connected by the peripheral part 41. Thus, the current collector plate 40 according to an embodiment of the present invention has a structure in which the tab connection part 42 and the terminal connection part 43 are not directly connected but are connected through the peripheral part 41 arranged on the outermost centripetal side in the radial direction. When an impact and / or vibration occurs in the battery 1, the impact applied to the connection site between the tab connection part 42 and the first electrode tab 11 and the connection site between the terminal connection part 43 and the terminal 50 can be dispersed. Therefore, the current collector plate 40 of the present invention can minimize or prevent damage to the welding site due to an external impact. When an external impact is applied to the current collector plate 40 of the present invention, the structure is such that stress is concentrated at the connection site between the peripheral part 41 and the terminal connection part 43. However, since such a connection site is not a site where a welding part for connecting parts is formed, it is possible to prevent product defects from occurring due to damage to the welding part caused by an external impact.

[0195] The current collector plate 40 may further include a connection part 44 that extends inward from the peripheral part 41 and is connected to the terminal connection part 43. At least a part of the connection part 44 may be formed to have a narrower width than the tab connection part 42. In this case, when the electrical resistance increases at the connection part 44 and current flows through the connection part 44, a larger resistance is generated compared to other parts, so that a part of the connection part 44 can be broken to cut off the overcurrent when the overcurrent occurs. The width of the connection part 44 can be adjusted to an appropriate level in consideration of such an overcurrent cutoff function.

[0196] The connecting portion 44 may include a tapered portion 44a whose width gradually narrows from the inner surface of the peripheral portion 41 toward the terminal connecting portion 43. When the tapered portion 44a is provided, the rigidity of the component is improved at the connecting site between the connecting portion 44 and the peripheral portion 41. Further, such a tapered portion 44a can function as a region covering the bent electrode tab.

[0197] A plurality of the tab connecting portions 42 may be provided. The plurality of tab connecting portions 42 may be arranged at the same intervals along the extending direction of the peripheral portion 41. The extending lengths of each of the plurality of tab connecting portions 42 may be the same as each other. The terminal connecting portion 43 may be arranged so as to be surrounded by the plurality of tab connecting portions 42. The connecting portion 44 may be located between a pair of adjacent tab connecting portions 42. In this case, the distance from the connecting portion 44 to one of the pair of tab connecting portions 42 along the extending direction of the peripheral portion 41 may be the same as the distance from the connecting portion 44 to the other of the pair of tab connecting portions 42 along the extending direction of the peripheral portion 41.

[0198] A plurality of the connecting portions 44 may be provided. Each of the plurality of connecting portions 44 may be arranged between a pair of adjacent tab connecting portions 42. The plurality of connecting portions 44 may be arranged at equal intervals along the extending direction of the peripheral portion 41.

[0199] As described above, when a plurality of tab connecting portions 42 and / or connecting portions 44 are provided, if the distances between the tab connecting portions 42 and / or the distances between the connecting portions 44 and / or the distances between the tab connecting portions 42 and the connecting portions 44 are formed to be constant, the flow of current from the tab connecting portion 42 toward the connecting portion 44 or from the connecting portion 44 toward the tab connecting portion 42 is smoothly formed.

[0200] The connecting portion 44 extends in the radial direction from the center of the current collecting plate 40 and may be in a form that extends linearly. Thereby, not only can the current conduction distance be shortened, but also when a compressive force or a tensile force is applied to one connecting portion 44 in its extending direction, the connecting portion 44 will not be greatly deformed, and the overall shape of the current collecting plate 40 can be prevented from being greatly deformed. As a result, the current collecting plate 40 will not shake excessively, and it can be prevented that the first electrode tab 11 pressed by the current collecting plate 40 floats or is deformed due to the shaking of the current collecting plate 40.

[0201] In addition, since a plurality of the linear connecting portions 44 are connected via the terminal connecting portion 43, when an external force is applied to one connecting portion 44 on one side with respect to the terminal connecting portion 43, the connecting portion 44 connected to the other side functions to support it. Furthermore, even when the tab connecting portion 42 and the terminal connecting portion 43 of the current collecting plate 40 receive forces in different axial directions, torsional stress will not be generated in the tab connecting portion 42 and the terminal connecting portion 43, and the welded part can be protected.

[0202] In the current collecting plate 40, the parts constrained by other parts in a way such as welding are the terminal connecting portion 43 and the tab connecting portion 42. Also, these are connected by the peripheral portion 41. The terminal connecting portion 43 is located at the center in the radial direction, the peripheral portion 41 is located at the end in the radial direction, and the tab connecting portion 42 is located between the center and the end in the radial direction.

[0203] Therefore, when the terminal connecting portion 43 receives a force relative to the tab connecting portion 42 in the radial direction or the axial direction, the linear connecting portion 44 transmits such a force to the peripheral portion 41, and the peripheral portion 41 extending in the circumferential direction can respond to such an external force while being flexibly deformed.

[0204] Referring to FIGS. 9 and 10, the connecting portion 44 may include a notching portion N formed by locally reducing the cross-sectional area along the extending direction of the connecting portion 44. The reduction of the cross-sectional area can be realized by reducing the width and / or thickness of the connecting portion 44. When the notching portion N is provided, the electrical resistance in the region where the notching portion N is formed increases, enabling rapid current interruption when an overcurrent occurs.

[0205] When the connecting portion 44 includes a tapered portion 44a, the notching portion N may be located closer to the tapered portion 44a than the terminal connection portion 43. In this case, due to the notching portion N being located adjacent to the region with a large heat generation amount due to the structure of the tapered portion 44a whose width gradually narrows, even more rapid overcurrent interruption becomes possible.

[0206] Referring to FIGS. 1 to 3 and FIG. 5, the terminal 50 is made of a conductive metal material and is coupled to the terminal connection portion 43 of the current collector plate (first current collector plate) 40. The terminal 50 may be configured to penetrate a closing portion located on the opposite side of the opening portion of the battery housing 20. When the battery 1 of the present invention includes an insulator 60, the terminal 50 is configured to pass through the insulator 60 and be coupled to the terminal connection portion 43 of the current collector plate 40.

[0207] As described above, the terminal 50 is electrically connected to the first electrode tab 11 of the electrode assembly 10 through the current collector plate 40, and thus has the first polarity. Therefore, the terminal 50 can function as the first electrode terminal of the battery 1 of the present invention. Further, in the battery 1 of the present invention, a substantially flat surface formed on the closing portion side of the battery housing 20 having the second polarity can function as the second electrode terminal 20a. Referring to FIG. 1, a bus bar B is connected to each of the first electrode terminal 50 and the second electrode terminal 20a of the battery 1 of the present invention. In each of the first electrode terminal 50 and the second electrode terminal 20a, in order to ensure a sufficient bonding area for bonding with the bus bar B, the width D1 of the region of the first electrode terminal 50 exposed outside the battery housing 20 can be set to about 10% to 60% with respect to the width D2 of the second electrode terminal 20a, that is, the upper surface of the battery housing 20.

[0208] When the terminal 50 has the first polarity in this way, the terminal 50 is electrically insulated from the battery housing 20 having the second polarity. The insulation between the terminal 50 and the battery housing 20 is realized in various ways. For example, insulation can be realized by interposing an insulating gasket G2 between the terminal 50 and the battery housing 20. The insulating gasket G2 can be made of, for example, a resin material having insulating properties.

[0209] Alternatively, insulation may be realized by forming an insulating coating layer on a part of the terminal 50. Or, a method of structurally and firmly fixing the terminal 50 may be applied so that the terminal 50 and the battery housing 20 cannot come into contact. Or, a combination of a plurality of the above-described methods may be applied.

[0210] Referring further to FIGS. 2, 3, and 5, the insulator 60 can be provided between the current collector plate (first current collector plate) 40 and the inner surface of the battery housing 20. The insulator 60 prevents contact between the current collector plate 40 and the battery housing 20. The insulator 60 can also be interposed between the upper end of the outer peripheral surface of the electrode assembly 10 and the inner surface of the battery housing 20. This is to prevent contact between the first electrode tab 11 extending toward the closing portion of the battery housing 20 and the inner peripheral surface of the battery housing 20.

[0211] When the battery 1 of the present invention includes the insulator 60, the terminal 50 passes through the insulator 60 and is coupled to the current collector plate 40. To allow the terminal 50 to pass through in this way, the insulator 60 can be provided with an opening formed at a position corresponding to the terminal coupling portion 43 of the current collector plate 40.

[0212] Referring to FIG. 11, the current collector plate (second current collector plate) 70 is coupled to the lower portion of the electrode assembly 10. The current collector plate 70 is made of a conductive metal material and is coupled to the second electrode tab 12. Also, the current collector plate 70 is electrically connected to the battery housing 20. The peripheral region of the current collector plate 70 can be interposed and fixed between the inner surface of the battery housing 20 and the sealing gasket G1. In this case, the current collector plate 70 may be welded onto the mounting surface formed by the beading portion 21 of the battery housing 20.

[0213] Referring to FIG. 4, the current collector plate 70 can be coupled to a coupling surface formed by bending the end of the second electrode tab 12 in a direction parallel to the current collector plate 70. The bending direction of the second electrode tab 12 can be, for example, a direction toward the winding center portion C of the electrode assembly 10. When the second electrode tab 12 has such a bent form, the space occupied by the second electrode tab 12 can be reduced, improving the energy density. Also, the effect of improving the bonding force and reducing the resistance between the second electrode tab 12 and the current collector plate 70 can be achieved.

[0214] On the one hand, in the present invention, the first electrode tab 11 and the second electrode tab 12 may each include a plurality of divided segments separated by cutting grooves regularly formed in the non-patterned portion along the winding direction of the electrode. The plurality of divided segments may be exposed outside the separation film along the winding axis direction. The plurality of divided segments may be aligned while overlapping along the radial direction of the electrode assembly to form a plurality of divided segment alignment portions separated in the circumferential direction. Further, the divided segments included in each divided segment alignment portion may be bent along the radial direction to form a bent surface region.

[0215] In such an embodiment, the tab coupling portion 42 of the current collector plate 40 is coupled to the bent surface region formed in the divided segment alignment portion, and the coupling portion 44 of the current collector plate 40 may be disposed between the divided segment alignment portions separated in the circumferential direction.

[0216] FIG. 13 is a plan view exemplarily showing an electrode structure provided with a plurality of divided segments for forming a plurality of divided segment alignment portions along the circumferential direction of the electrode assembly.

[0217] Referring to FIG. 13, the electrode 80 of the present embodiment includes a sheet-shaped current collector 81 and an active material layer 82. The current collector 81 may be made of a metal foil. The metal foil may be made of a conductive metal, such as aluminum or copper. The current collector 81 may be appropriately selected according to the polarity of the electrode 80. The metal foil can be replaced with a metal mesh or the like. The metal foil may have a structure in which a metal thin film is coated on both sides of a substrate made of an insulating film. The active material layer 82 is formed on at least one surface of the current collector 81. The active material layer 82 is formed along the winding direction X. The electrode 80 includes a non-patterned portion 83 at the long side end in the winding direction X. The non-patterned portion 83 is a partial region of the current collector 81 not coated with the active material. In the electrode 80, the region of the current collector 81 where the active material layer 82 is formed may be referred to as the active material portion.

[0218] In the electrode 80, the width of the current collector 81 in the short side direction can be 60 mm to 70 mm, and the length of the current collector 81 in the long side direction can be 3 m to 5 m. Therefore, the ratio of the short side to the long side of the electrode 80 can be 1.2% to 2.3%. This ratio is significantly smaller than the ratio of the short side to the long side at the level of 6% to 11% in the electrode used in a cylindrical battery having a form factor of 1865 or 2170.

[0219] Desirably, an insulating coating layer 84 can be formed at the boundary between the active material layer 82 and the plain portion 83. The insulating coating layer 84 is formed so as to overlap at least a part of the boundary between the active material layer 82 and the plain portion 83. The insulating coating layer 84 prevents a short circuit between two electrodes of opposite polarities facing each other with a separator interposed therebetween. The insulating coating layer 84 can cover the boundary portion between the active material layer 82 and the plain portion 83 with a width of 0.3 mm to 5 mm. The insulating coating layer 84 contains a polymer resin and may contain inorganic fillers such as Al2O3 and SiO2. Since the portion of the current collector 81 covered by the insulating coating layer 84 is not a region coated with the active material layer, it can be regarded as a plain portion.

[0220] The plain portion 83 includes a first portion B1 adjacent to the core side, a second portion B3 adjacent to the outer peripheral side, and a third portion B2 interposed between the first portion B1 and the second portion B3. The core and the outer periphery refer to the central region and the outer peripheral surface of the electrode assembly when the electrode 80 is wound as an electrode assembly.

[0221] Among the first portion B1, the second portion B3, and the third portion B2, the length of the third portion B2 is the longest and occupies most of the length of the electrode 80. The first portion B1 can form a plurality of winding turns adjacent to the core of the electrode assembly. The second portion B3 can form one or more winding turns adjacent to the outer periphery of the electrode assembly.

[0222] Part 3 B2 includes a plurality of segmented pieces 85. Since the plurality of segmented pieces 85 are used for electrical connection with the current collector plate 40, they correspond to the first electrode tabs 11. Desirably, the segmented pieces 85 can be square-shaped. Alternatively, the segmented pieces 85 can be trapezoidal, parallelogram-shaped, semi-circular, etc. The geometric form of the segmented pieces 85 can be variously deformed.

[0223] The plurality of segmented pieces 85 can be notched by a laser. Alternatively, the segmented pieces 85 can be formed by known metal foil cutting processes such as ultrasonic cutting or punching. In the winding direction X, the interval (pitch) between the segmented pieces 85 can increase from the core side toward the outer peripheral side.

[0224] A cutting groove 86 is interposed between adjacent segmented pieces 85 in the winding direction X. The cutting groove 86 is formed in the notching process of the segmented pieces 85. The cutting groove 86 includes a flat bottom 86a, a rounded portion 86b adjacent thereto, and a side portion 86c of the segmented piece 85. Here, the rounded portion 86b can prevent cracks from occurring at the lower end of the segmented piece 85 by relaxing the stress when the segmented piece 85 is bent.

[0225] In order to prevent the active material layer 82 and / or the insulating coating layer 84 from being damaged during the bending process of the segmented slice 85, it is desirable to provide a predetermined gap between the bottom 86a of the cutting groove 86 and the active material layer 82. This is because when the segmented slice 85 is bent, stress is concentrated near the bottom 86a of the cutting groove 86. The gap is desirably in the range of 0.2 mm to 4 mm, preferably 1.5 mm to 2.5 mm. When the gap is adjusted within the above numerical range, it is possible to prevent the active material layer 82 and / or the insulating coating layer 84 near the lower end of the cutting groove 86 from being damaged by the stress generated during the bending process of the segmented slice 85. Also, the gap can prevent damage to the active material layer 82 and / or the insulating coating layer 84 due to the tolerance during the notching or cutting of the segmented slice 85. The lower end of the cutting groove 86 and the insulating coating layer 84 can be separated by 0.5 mm to 1.0 mm. When the electrode 80 is wound, the end of the insulating coating layer 84 in the winding axis (Y-axis) direction can be positioned in the range of -2 mm to 2 mm along the winding axis direction with reference to the end of the separator. The insulating coating layer 84 can prevent a short circuit between two electrodes of opposite polarities facing each other with the separator interposed therebetween, and can support the bending point when the segmented slice 85 is bent. To improve the short circuit prevention effect between the two electrodes, the insulating coating layer 84 can be exposed outside the separator. Also, to further maximize the short circuit prevention effect between the two electrodes, the width of the insulating coating layer 84 may be increased so that the end of the insulating coating layer 84 in the winding axis (Y-axis) direction is positioned above the bottom 86a of the cutting groove 86. In one example, the end of the insulating coating layer 84 in the winding axis direction can be positioned within the range of -1 mm to +1 mm with reference to the bottom 86a of the cutting groove 86.

[0226] FIG. 14 is a top plan view of the upper part of the electrode assembly JR manufactured by winding the positive electrode and the negative electrode having the structure of the electrode 80 shown in FIG. 13 together with the separator, FIG. 15 is a perspective view partially showing the upper part of the electrode assembly JR, and FIG. 16 is a partial cross-sectional view taken along the line A-A' of FIG. 14. The upper part of the electrode assembly JR shown in the drawings is the positive electrode side.

[0227] Referring to FIGS. 14 to 16 together, a plurality of segment pieces 85 protrude outside the separation membrane and are exposed in the winding shaft direction (Y-axis). Further, the plurality of segment pieces 85 are radially arranged with respect to the center of the core C of the electrode assembly JR to form a segment piece alignment portion 90. The segment piece alignment portion 90 means an aggregate of segment pieces 85 in which segment pieces 85 located in different winding turns are arranged while overlapping in the radial direction of the electrode assembly JR.

[0228] That the plurality of segment pieces 85 included in the segment piece alignment portion 90 overlap in the radial direction means that when a virtual straight line passing through the segment piece alignment portion 90 from the center of the core C is drawn, all the segment pieces 85 intersect the virtual straight line.

[0229] The segment piece alignment portion 90 has a structure extending along the radial direction of the electrode assembly JR by a predetermined length. In the segment piece alignment portion 90, the segment pieces 85 of adjacent winding turns in the radial direction can overlap each other in the circumferential angle measured with respect to the core center.

[0230] The number of the segment piece alignment portions 90 can be four, three, or two, but the number of the segment piece alignment portions 90 is not limited thereto. When there are a plurality of segment piece alignment portions 90, the segment piece alignment portions 90 can be arranged at equal intervals in the circumferential direction. Of course, it is not excluded that the segment piece alignment portions 90 are arranged at unequal intervals in the circumferential direction.

[0231] When the number of the segment piece alignment portions 90 is four, the angle between adjacent segment piece alignment portions 90 in the circumferential direction can be about 90°. When the number of the segment piece alignment portions 90 is three, the angle between adjacent segment piece alignment portions 90 in the circumferential direction can be about 120°. When the number of the segment piece alignment portions 90 is two, the angle between adjacent segment piece alignment portions 90 in the circumferential direction can be about 180°.

[0232] The angle θ between adjacent segment alignment portions 90 in the circumferential direction is defined as the angle formed by the extension line of a side of one segment alignment portion 90 and the extension line of the side of the other segment alignment portion 90 closest to the segment alignment portion 90 when the electrode assembly JR is viewed from the winding axis direction (Y-axis). The angle θ is substantially the same as the angle formed by adjacent virtual lines in the circumferential direction when a virtual line (refer to the dashed line) passing through the center of the segment alignment portion 90 from the center of the core C of the electrode assembly JR is drawn.

[0233] The separation pitch between adjacent segments 85 in the winding direction X increases from the core side toward the outer peripheral side in the winding direction X of the electrode assembly JR, and can be determined according to a rule preset so that the segment alignment portions 90 are formed in the radial direction of the electrode assembly JR. The separation pitch of the segments 85 substantially corresponds to the width in the winding direction of the cutting groove 86.

[0234] An electrolyte impregnation portion 100 is formed between adjacent segment alignment portions 90 in the circumferential direction of the electrode assembly JR. The electrolyte impregnation portion 100 is formed while the plain portion 83 region where the cutting groove 86 is formed is wound.

[0235] As shown in FIG. 16, the electrolyte impregnated portion 100 is a section mainly impregnated with the electrolyte EL, and has a height lower than the height of the segmented slice alignment portion 90 in the winding axis direction (Y-axis). There is no segmented slice 85 protruding outside the separator Se in the electrolyte impregnated portion 100. Also, in the electrolyte impregnated portion 100, between the separators Se adjacent to each other in the radial direction of the electrode assembly JR, the end portion of the active material layer a1 of the positive electrode E1 and the end portion of the active material layer a2 of the negative electrode E2 are separated by a predetermined distance below the end portion of the separator Se. Thereby, insulation between the positive electrode E1 and the negative electrode E2 is maintained. In one example, the separation distance can be 0.6 mm to 1 mm. An insulating coating layer 84 may be formed on at least one of the end portion of the positive electrode E1 and the end portion of the negative electrode E2. The end portion of the positive electrode E1 may include a slide portion where the thickness of the active material layer a1 gradually decreases. The arrangement structure of the electrodes and the separator shown in FIG. 16 can also be applied to the lower part of the electrode assembly JR. Desirably, in the lower part of the electrode assembly JR, the insulating coating layer 84 and the slide portion can be formed on the end portion of the negative electrode E2.

[0236] The electrolyte EL can impregnate into the electrode assembly JR while directly contacting the positive electrode E1 and the negative electrode E2 through a gap provided between the end portions of the separator Se. Specifically, the electrolyte EL dropped on the upper part of the electrode assembly JR quickly penetrates into the electrode assembly JR while simultaneously contacting the end portions of the positive electrode E1 and the negative electrode E2 and the end portion of the separator Se. Thereby, the electrolyte impregnation property (speed and uniformity) is remarkably improved.

[0237] Desirably, the height H of the segment 85 can be substantially the same in the radial direction of the electrode assembly JR. As an example, the height of the segment 85 can be 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm. Alternatively, the height H of the segment 85 can increase stepwise from the core side to the outer peripheral side of the electrode assembly JR. As an example, the height of the segment 85 can increase stepwise in the range of 2 mm to 10 mm. In one example, when the core diameter of the electrode assembly JR is 8 mm, the height of the segment 85 can increase by 1 mm each from 2 mm to 10 mm in a radial section of 6 mm to 14 mm. If the height H of the segment 85 increases stepwise, the number of layers of the segment 85 can be increased at the bent surface of the segment 85, and the length of the region with a uniform number of layers can be increased in the radial direction of the electrode assembly JR.

[0238] The width W of the segment 85 is desirably substantially the same as or relatively larger than the width of the tab joint portion 42 of the current collector plate 40. The width W of the segment 85 can be appropriately selected in the range of 3 mm to 11 mm, for example.

[0239] Referring to FIGS. 13 and 16, the bending point 87 of the segment 85 can be set at a line passing through the bottom 86a of the cutting groove 86 or a point separated from that line by a predetermined distance upward. When the segment 85 is bent toward the core side at a point separated from the lower end of the cutting groove 86 by a predetermined distance, the overlapping of the segments in the radial direction is more easily performed. When the segments 85 are bent, the outer segments press the inner segments with respect to the center of the core. At this time, if the bending point 87 is separated from the lower end of the cutting groove 86 by a predetermined distance, the overlapping of the segment 85 is performed more smoothly while the inner segment is pushed in the winding axis direction by the outer segment. The separation distance of the bending point 87 can be 3 mm or less, desirably 2 mm or less.

[0240] The separation pitch of the segments 85 corresponds to the width of the cutting groove 86 in the winding direction X, and can be determined in advance so that when the electrode 80 is wound, the segment alignment portion 90 is formed in the radial direction of the electrode assembly JR in a preset region.

[0241] FIG. 17 is a diagram showing a step of coupling the current collector plate 40 to the upper part of the electrode assembly JR using a bent surface region F formed while the segment 85 included in the segment alignment unit 90 is bent toward the core side of the electrode assembly JR according to an embodiment of the present invention.

[0242] Referring to FIG. 17, the segments 85 included in the plurality of segment alignment units 90 can be bent toward the core side of the electrode assembly JR to form a bent surface region F. The surface of the bent surface region F is substantially perpendicular to the winding axis direction of the electrode assembly JR. The bent surface region F corresponds to a region where the segments 85 are laminated while overlapping multiple times in the winding axis direction. The number of laminated segments 85 can desirably be 10 or more. Since the bent surface region F is formed at the upper part of the segment alignment unit 90, the segment alignment unit 90 is understood as a component including the bent surface region F.

[0243] FIGS. 18a and 18b are top views showing a state where the current collector plate 40 according to an embodiment of the present invention is welded to the upper part of the electrode assembly JR.

[0244] Referring to FIGS. 18a and 18b, each tab coupling part 42 included in the current collector plate 40 can be coupled to the bent surface region F formed at the upper part of the corresponding segment alignment unit 90 through welding.

[0245] The bent surface region F is flat and wider than the tab coupling part 42, so the tab coupling part 42 can be welded in a state of being easily placed on the bent surface region F.

[0246] The connecting part 44 is disposed on the upper part of the electrolyte impregnation part 100 formed between adjacent segment alignment units 90 in the circumferential direction. As shown in FIG. 16, in the electrolyte impregnation part 100, the ends of the positive electrode E1 and the negative electrode E2 are separated from the end of the separator Se by a predetermined interval downward. Therefore, the connecting part 44 can also be electrically insulated from the ends of the electrodes by being separated from the ends of the positive electrode E1 and the negative electrode E2.

[0247] In FIGS. 18a and 18b, reference numeral W indicates a welding pattern. The welding pattern W can be formed by at least one continuous or discontinuous linear pattern in the extending direction of the tab joint portion 42. The welding pattern W can be formed by laser welding. Alternatively, the welding pattern W can be formed by other known welding methods such as ultrasonic welding and resistance welding.

[0248] The connecting portion 44 is disposed above the electrolyte impregnated portion 100 with reference to the winding axis direction (Y-axis). Further, since the bending point of the segmented piece 85 is separated from the electrolyte impregnated portion 100 as shown in FIG. 16, there may be a predetermined gap corresponding to the space formed between the bending surface region F formed while the segmented piece 85 is bent and the electrolyte impregnated portion 100.

[0249] Therefore, when the notching portion N of the connecting portion 44 is broken by an overcurrent, the electrical connection between the terminal joint portion 43 and the tab joint portion 42 is completely interrupted by the gap.

[0250] On the other hand, when the bending surface region F is formed on the entire surface of the end portion of the electrode assembly JR, even if the notching portion N is broken by an overcurrent, the electrical connection state between the terminal joint portion 43 and the tab joint portion 42 can be indirectly maintained through the bending surface region F.

[0251] Therefore, it is more desirable to locally form the bending surface region F only in a partial region of the end portion of the electrode assembly JR by adjusting the separation pitch between the segmented pieces 85, and to dispose the connecting portion 44 including the notching portion N in a region without the bending surface region F in terms of reliably interrupting the overcurrent.

[0252] FIG. 19a is a plan view showing the structure of the electrode 80 according to another embodiment of the present invention, and FIG. 19b is a top plan view showing the structure of the segmented piece alignment portion 90 formed on the upper portion of the electrode assembly in which the structure of the electrode 80 of FIG. 19a is applied to the positive electrode and the negative electrode.

[0253] Referring to FIGS. 19a and 19b, the electrode 80 according to another embodiment of the present invention has a structure in which the segmented piece groups 85g are separated by a separation pitch between the groups. The separation pitch may gradually or stepwise increase along the winding direction X. The segmented piece group 85g may include at least one segmented piece 85. The shape of the segmented piece 85 is rectangular. However, the shape of the segmented piece 85 may be changed to other geometric figures such as a trapezoid.

[0254] The segmented piece groups 85g form a segmented piece alignment portion 90 by being arranged overlapping along the radial direction when the electrode assembly is wound. The segmented piece alignment portion 90 is substantially fan-shaped. The segmented pieces 85 included in the segmented piece alignment portion 90 may be bent toward the core C to form a bent surface region F. The tab coupling portion 42 of the current collector plate 40 may be welded to the bent surface region F formed in the segmented piece alignment portion 90 in the same manner as in the above-described embodiment. Further, the connecting portion 44 of the current collector plate 40 may be disposed on the upper portion of the electrolyte impregnation portion 100 located between the adjacent segmented piece alignment portions 90 in the circumferential direction.

[0255] The cylindrical battery to which the above-described embodiment of the present invention is applied may be a cylindrical battery having, for example, a form factor ratio (a value obtained by dividing the diameter of the cylindrical battery by the height, that is, a ratio of the height (H) to the diameter (Φ)) greater than about 0.4.

[0256] Here, the form factor means a value indicating the diameter and height of the cylindrical battery. The cylindrical battery according to an embodiment of the present invention may be, for example, a 46110 battery, a 4875 battery, a 48110 battery, a 4880 battery, or a 4680 battery. In the numerical value indicating the form factor, the first two digits indicate the diameter of the battery, and the remaining digits indicate the height of the battery.

[0257] The battery according to an embodiment of the present invention may be a substantially cylindrical battery having a diameter of about 46 mm, a height of about 110 mm, and a form factor ratio of about 0.418.

[0258] Batteries according to other embodiments may be cylindrical batteries that are substantially cylindrical, having a diameter of about 48 mm, a height of about 75 mm, and a form factor ratio of about 0.640.

[0259] Batteries according to yet other embodiments may be cylindrical batteries that are substantially cylindrical, having a diameter of about 48 mm, a height of about 110 mm, and a form factor ratio of about 0.436.

[0260] Batteries according to yet other embodiments may be cylindrical batteries that are substantially cylindrical, having a diameter of about 48 mm, a height of about 80 mm, and a form factor ratio of about 0.600.

[0261] Batteries according to yet other embodiments may be cylindrical batteries that are substantially cylindrical, having a diameter of about 46 mm, a height of about 80 mm, and a form factor ratio of about 0.575.

[0262] Conventionally, batteries with a form factor ratio of about 0.4 or less have been used. That is, conventionally, for example, 1865 batteries, 2170 batteries, etc. have been used. In the case of an 1865 battery, the diameter is about 18 mm, the height is about 65 mm, and the form factor ratio is about 0.277. In the case of a 2170 battery, the diameter is about 21 mm, the height is about 70 mm, and the form factor ratio is about 0.300.

[0263] Referring to FIG. 20, a battery pack 3 according to an embodiment of the present invention includes a battery assembly in which a plurality of batteries 1 according to an embodiment of the present invention as described above are electrically connected, and a pack housing 2 that houses the same. For the sake of illustration, components such as bus bars, cooling units, and power terminals for electrical connection are not shown.

[0264] Referring to FIG. 21, a vehicle 5 according to an embodiment of the present invention can be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle, and includes a battery pack 3 according to an embodiment of the present invention. The vehicle 5 includes four-wheel vehicles and two-wheel vehicles. The vehicle 5 operates by receiving power supply from the battery pack 3 according to an embodiment of the present invention.

[0265] Although the present invention has been described with reference to the drawings exemplifying the present invention as above, it is obvious that the present invention is not limited by the embodiments and the drawings shown in this specification, and can be variously modified by an ordinary technician within the scope of the technical idea of the present invention. Furthermore, it goes without saying that even when the effects of the configuration of the present invention are not explicitly stated in the description of the embodiment, the effects predictable by the corresponding configuration must also be recognized.

[0266] 5 Vehicle 10 Electrode assembly 11 First electrode tab 12 Second electrode tab 20 Battery housing 21 Beading part 22 Crimping part 30 Cap plate 31 Venting part 40 Current collector plate (first current collector plate) 41 Peripheral part 42 Tab connection part 43 Terminal connection part 44 Connection part 50 First electrode terminal 60 Insulator 70 Current collector plate (second current collector plate) 80 Electrode 81 Current collector 82 Active material layer 83 Plain part 84 Insulating coating layer 85 Segment 86 Cutting groove 87 Bending point 90 Segment alignment part 100 Electrolyte impregnation part

Claims

1. A current collector plate that electrically connects the first electrode tab and the terminal between the first electrode tab of the electrode assembly and the terminal exposed to the outside, a peripheral portion that extends in the circumferential direction and defines a space inside, a tab coupling portion that extends from the peripheral portion toward the center and is coupled to the first electrode tab, a terminal coupling portion disposed closer to the center than the peripheral portion, a connecting portion that connects the peripheral portion and the terminal coupling portion without contacting the tab coupling portion, The current collector plate including.

2. The current collector plate according to claim 1, wherein among the terminal coupling portion, the peripheral portion, and the tab coupling portion, the peripheral portion is disposed on the outermost side in the radial direction, and the terminal coupling portion is disposed on the innermost side in the radial direction.

3. The current collector plate according to claim 1, wherein the center of the terminal coupling portion and the center of the peripheral portion substantially coincide.

4. A plurality of the tab coupling portions are arranged along the circumferential direction of the peripheral portion, The current collector plate according to claim 1, wherein the terminal coupling portion is connected to a portion of the peripheral portion provided between two adjacent tab coupling portions in the circumferential direction.

5. Based on an imaginary line connecting the connection portions of two adjacent tab coupling portions and the peripheral portion with a straight line, the portion of the peripheral portion provided between two adjacent tab coupling portions is disposed further on the outermost side than the imaginary line. The current collector plate according to claim 4.

6. The current collector plate according to claim 4, wherein the plurality of tab coupling portions are arranged at equal intervals along the circumferential direction of the peripheral portion.

7. The current collector plate according to claim 4, wherein the extension lengths of the plurality of tab coupling portions correspond to each other.

8. The current collector plate according to claim 4, wherein the terminal coupling portion is arranged so as to be surrounded by the plurality of tab coupling portions.

9. The current collector plate according to claim 4, wherein the plurality of tab coupling portions are separated from the terminal coupling portion in the radial direction and are arranged radially around the terminal coupling portion.

10. The current collector plate according to claim 1, wherein the peripheral portion has a rim shape with a central portion being empty.

11. The terminal coupling portion is disposed at or near the center of the central region closer to the center than the peripheral portion, The current collector plate according to any one of claims 1 to 10, wherein the peripheral portion and the terminal coupling portion are connected by the connecting portion that extends in the space between the peripheral portion and the terminal coupling portion without contacting the tab coupling portion.

12. The current collector plate according to claim 11, wherein the connecting portion extends linearly to connect the terminal connecting portion and the peripheral portion.

13. The current collector plate according to claim 12, wherein the connecting portion extends substantially in the radial direction from the center of the terminal connecting portion and is connected to the peripheral portion.

14. The current collector plate according to claim 13, wherein a plurality of the connecting portions are provided and arranged at equal intervals along the outer periphery of the terminal connecting portion.

15. The current collector plate according to claim 12, wherein the plurality of connecting portions are arranged at the same interval along the circumferential direction of the peripheral portion.

16. The current collector plate according to claim 11, wherein at least a part of the width of the connecting portion is formed narrower than that of the tab connecting portion.

17. The current collector plate according to claim 11, wherein the connecting portion includes a tapered portion whose width gradually narrows in a direction from the inner peripheral surface of the peripheral portion toward the terminal connecting portion.

18. The current collector plate according to claim 11, wherein the connecting portion is located between a pair of adjacent tab connecting portions in the circumferential direction.

19. The current collector plate according to claim 18, wherein the distance from the connecting portion to one of the pair of tab connecting portions along the circumferential direction corresponds to the distance from the connecting portion to the other of the pair of tab connecting portions along the circumferential direction.

20. The current collector plate according to claim 11, wherein the connecting portion includes a notching portion whose cross-sectional area locally decreases in its extending direction.

21. The current collector plate according to claim 20, wherein the notching portion is located closer to the peripheral portion than the terminal connecting portion.

22. The current collector plate according to claim 1, wherein a portion of the tab connecting portion facing the terminal connecting portion has a tapered shape toward the terminal connecting portion.

23. The current collector plate according to claim 1, having a radially symmetric structure.

24. The current collector plate according to claim 23, having a radially symmetric structure by rotation of 90°, 120°, or 180°.

25. An electrode assembly in which a first electrode, a second electrode, and a separation film interposed between the first electrode and the second electrode are wound around a winding axis to define a core and an outer peripheral surface, wherein the first electrode and the second electrode each include a first electrode tab formed of a first non-patterned portion and a second electrode tab formed of a second non-patterned portion at long-side ends along the winding direction, and the first electrode tab and the second electrode tab project outward of the separation film in opposite directions in the winding axis direction. A battery housing that houses the electrode assembly and is electrically connected to the second electrode tab; A terminal that is insulatingly attached to the battery housing and is exposed to the outside; A current collector plate that electrically connects the first electrode tab and the terminal between the first electrode tab and the terminal, having a peripheral portion that defines a space inside, a tab coupling portion that extends from the peripheral portion toward the center and is coupled to the first electrode tab, a terminal coupling portion that is disposed on the center side from the peripheral portion, and a connecting portion that connects the terminal coupling portion and the peripheral portion without contacting the tab coupling portion; comprising; A battery, wherein the first electrode tab is coupled to the tab coupling portion of the current collector plate, and the terminal is coupled to the terminal coupling portion of the current collector plate.

26. The first electrode tab includes a plurality of divided sections separated by a cutting groove along the winding direction and protruding outside the separation film along the winding axis direction; The plurality of divided sections are aligned while overlapping along the radial direction of the electrode assembly to constitute a plurality of divided section alignment portions spaced apart in the circumferential direction; The divided sections included in each divided section alignment portion are bent along the radial direction to form a bent surface region; The tab coupling portion of the current collector plate is coupled to the bent surface region; The battery according to claim 25, wherein the connecting portion is disposed between the divided section alignment portions spaced apart in the circumferential direction.

27. The connecting portion includes a notching portion having a reduced cross-sectional area in its extending direction; The battery according to claim 26, wherein the notching portion is spaced apart from an end surface of the electrode assembly exposed between the divided section alignment portions spaced apart in the circumferential direction.

28. The battery according to claim 26 or 27, wherein an end surface of the electrode assembly exposed between the divided section alignment portions spaced apart in the circumferential direction is an electrolyte impregnation portion.

29. The battery according to claim 28, wherein, in the electrolyte impregnation portion, end portions of the first electrode and the second electrode in the winding axis direction are exposed from between separation films of adjacent winding turns.

30. The battery according to claim 25, wherein the terminal coupling portion is disposed at a position corresponding to a hole formed in a winding center portion of the electrode assembly.

31. The battery housing includes an opening portion on one side in the axial direction and a closing portion on the other side in the axial direction. The battery according to claim 25, wherein the first electrode tab faces the closed portion, and the second electrode tab faces the open portion.

32. The battery housing includes an open portion on one axial side and a closed portion on the other axial side, and the open portion is sealed by a cap plate. A sealing gasket is interposed between the cap plate and the open portion. The battery according to claim 25, wherein the cap plate is not connected to the first electrode tab and the second electrode tab of the electrode assembly and has no polarity.

33. The battery housing includes an open portion on one axial side and a closed portion on the other axial side. The battery according to claim 25, wherein the terminal is disposed through a through hole in the closed portion, and an insulating gasket is interposed between the terminal and the through hole.

34. The battery according to claim 33, further including an insulator interposed between the closed portion and the current collector plate.

35. The battery according to claim 34, wherein the terminal passes through the insulator and is coupled to the terminal coupling portion of the current collector plate.

36. A battery pack including the battery according to claim 25, and a pack housing for accommodating a plurality of the batteries.

37. An automobile including the battery pack according to claim 36.

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