Patent Description:
The present application claims priority to <CIT>, <CIT>, and <CIT>.

Batteries that can be repeatedly recharged have a wide range of applications. Battery packs applied to, for example, devices such as electric vehicles require high capacity and high output. A battery pack having high capacity and high output may include a plurality of batteries.

The battery having high capacity and high output characteristics has an electrode tab over two end surfaces of a jelly roll to increase the current collection efficiency, and a current collector plate may be coupled to each of the two end surfaces of the jelly roll. This structure may maximize the contact area of the electrode tab and the current collector plate and minimize the resistance at the connected part of the components.

As described above, when batteries are applied to, for example, devices such as vehicles, external impacts and vibrations may be frequently applied while in use, causing damage to a coupled part for electrical connection between components. The damaged coupled part causes product defects.

Alternatively, even though the electrical connection is not completely disconnected by the damaged coupled part for electrical connection, when a portion of the welded part is damaged and the coupling area between components reduces, the increased resistance may result in excessive heat generation or component deformation, causing an internal short.

Accordingly, there is a need for the development of batteries having a structure for preventing force concentration at the coupled part between components when external impacts and/or vibrations are applied while in use.

There is a conventional flexible current collector plate having a flat plate shape that deforms in the axial direction of the battery. However, each time the flat plate shaped-current collector plate deforms in the axial direction, torsion stress is applied to the joined (welded) part of the current collector plate, causing a disconnection at the contact point of the current collector plate.

The present disclosure is designed to address the above-described problem, and therefore the present disclosure is directed to proving a battery for the dissipation of external impacts and/or vibrations without concentration on a specific location when the impacts and/or vibrations are applied while in use, thereby preventing damage from occurring at a coupled part between components.

The present disclosure is further directed to proving a current collector plate having a structure that keeps it flat and provides flexibility in the axial direction and the radial direction, thereby eliminating the risk of torsion stress at a contact point when deformation occurs.

The present disclosure is further directed to proving a current collector plate that can perform a current interrupt function without additionally installing a current interrupt member to interrupt an electric current quickly when an overcurrent occurs due to a short circuit, thereby ensuring safety of a battery while in use.

The objectives of the present disclosure are not limited to the above-mentioned objectives, and these and other objectives and advantages of the present disclosure may be understood by the following description, and will be understood more clearly by an embodiment of the present disclosure. Additionally, it is apparent that the objectives and advantages of the present disclosure may be realized by the means set forth in the appended claims and a combination thereof.

The present disclosure provides a current collector plate disposed between a first electrode tab of an electrode assembly and an exposed terminal for electrical connection thereof.

The current collector plate includes an edge portion extended in a circumferential direction; a tab coupling portion extended from an edge portion in a centripetal direction and coupled to the first electrode tab; and a terminal coupling portion disposed at a centripetal position relative to the edge portion and connected to the tab coupling portion through the edge portion while avoiding the tab coupling portion.

Among the terminal coupling portion, the edge portion and the tab coupling portion, the edge portion may be disposed at an outermost centrifugal position, and the terminal coupling portion may be disposed at an innermost centripetal position.

A center of the terminal coupling portion may substantially match a center of the edge portion.

The edge portion may have a rim shape with a hollow center.

The edge portion may have a substantially circular flat ring shape.

A plurality of the tab coupling portions may be arranged along the circumferential direction of the edge portion.

An extended length of each of the plurality of tab coupling portions may correspond to each other.

The plurality of tab coupling portions may be arranged at equal intervals along the circumferential direction of the edge portion.

The tab coupling portion may be extended from the inner circumference of the edge portion in the centripetal direction.

On the basis of an imaginary line connecting connected parts of the two adjacent tab coupling portions in the circumferential direction and the edge portion in a straight line shape, the edge portion between the two adjacent tab coupling portions may be disposed at a more centrifugal position than the imaginary line.

The terminal coupling portion may be connected to the edge portion between the two adjacent tab coupling portions in the circumferential direction.

The terminal coupling portion may be disposed at or near a center of a centripetal area relative to the edge portion, and the edge portion and the terminal coupling portion may be connected by a connection portion.

The connection portion may be extended more outwards in the radial direction than the tab coupling portion.

The terminal coupling portion may be surrounded by the plurality of tab coupling portions.

The plurality of tab coupling portions may be spaced apart from the terminal coupling portion in the radial direction, and may be radially arranged around the terminal coupling portion.

The connection portion may be linearly extended in the shape of a straight line to connect the terminal coupling portion to the edge portion.

The connection portion may have a straight line shape that passes through the center of the current collector plate.

The connection portion may be extended from the terminal coupling portion in the radial direction and connected to the edge portion.

The connection portion may be substantially extended from the center of the terminal coupling portion in the radial direction and connected to the edge portion.

A plurality of the connection portions may be provided and arranged at equal intervals along an outer circumference of the terminal coupling portion.

The plurality of connection portions may be arranged at equal intervals along the circumferential direction of the edge portion.

The connection portion may be disposed between a pair of adjacent tab coupling portions in the circumferential direction.

A distance from the connection portion to any one of the pair of tab coupling portions along the circumferential direction may correspond to a distance from the connection portion to the other one of the pair of tab coupling portions along the circumferential direction.

The electrical conduction pathway from the terminal coupling portion to the tab coupling portion may be in an order of the terminal coupling portion, the connection portion, the edge portion and the tab coupling portion.

At least part along the extension direction of the connection portion may have a smaller width than the tab coupling portion.

The connection portion may include a tapered portion having a gradual reduction in width along a direction from the inner circumferential surface of the edge portion toward the terminal coupling portion.

The connection portion may include a notching portion having a local reduction in cross sectional area in the extension direction thereof.

The notching portion may be disposed closer to the edge portion than the terminal coupling portion.

A part of the tab coupling portion facing the terminal coupling portion may have a tapered shape toward the terminal coupling portion.

The current collector plate may have a radially symmetric structure.

The current collector plate may have the radially symmetric structure by <NUM>°, <NUM>° or <NUM>° rotation.

The current collector plate may be used in a battery.

The battery including the current collector plate may include an electrode assembly and a battery housing accommodating the electrode assembly.

The electrode assembly may include a first electrode and a second electrode and a separator interposed therebetween wound together around a winding axis to define a core and an outer circumferential surface, wherein the first electrode and the second electrode have a first electrode tab formed of a first uncoated portion and a second electrode tab formed of a second uncoated portion at a long side end along a winding direction, respectively, and the second electrode tab and the second electrode tab protrude from the separator in opposite directions along the winding axis direction.

The battery may include a terminal installed to be insulated from the battery housing and exposed outside of the battery housing.

The current collector plate may include an edge portion which defines a space inside; a tab coupling portion extended from the edge portion in the centripetal direction and coupled to the first electrode tab; and a terminal coupling portion disposed at a centripetal position relative to the edge portion; and a connection portion connecting the terminal coupling portion to the edge portion while avoiding the tab coupling portion.

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.

The first electrode tab may be separated by cutout grooves along the winding direction, and may include a plurality of segments that protrudes from the separator along the winding axis direction.

The plurality of segments may be arranged to be overlapped along the radial direction of the electrode assembly so as to form a plurality of segment alignments spaced apart from each other in the circumferential direction.

The segments included in each segment alignment may be bent along the radial direction to form a bent surface region.

The tab coupling portion of the current collector plate may be coupled to the bent surface region, and the connection portion may be positioned between the segment alignments spaced apart from each other in the circumferential direction.

The connection portion may include a notching portion having a reduction in cross sectional area in the extension direction thereof, and the notching portion may be spaced apart from an exposed end surface of the electrode assembly between the segment alignments spaced apart from each other in the circumferential direction.

The exposed end surface of the electrode assembly between the segment alignments spaced apart from each other in the circumferential direction may be an electrolyte impregnation portion.

In the electrolyte impregnation portion, an end of the first electrode and an end of the second electrode in the winding axis direction may be exposed between the separators of an adjacent winding turn.

The battery housing may have a closed portion on one side in the axial direction and an open portion on the other side.

The electrode assembly including the first electrode tab and the second electrode tab may be inserted through the open portion.

The first electrode tab and the second electrode tab of the electrode assembly may be positioned on one side and the other side in the axial direction respectively.

When the electrode assembly is received in the battery housing, the first electrode tab may face the closed portion, and the second electrode tab may face the open portion.

The terminal may be disposed at the closed portion.

The terminal may pass through the closed portion.

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

The terminal coupling portion of the current collector plate may be disposed at a location corresponding to a hole at a winding center of the electrode assembly.

The end of the first electrode tab may be bent in the radial direction.

The first electrode tab may be bent in the centripetal direction or the centrifugal direction.

The tab coupling portion of the current collector plate may be coupled to the surface of the bent first electrode tab.

The connection portion may face and contact the surface of the bent first electrode tab.

The edge portion may face and contact the surface of the bent first electrode tab.

The open portion of the battery housing may be closed by the cap plate.

The cap plate may not be electrically connected to the first electrode tab and the second electrode tab of the electrode assembly. Accordingly, the cap plate may be non-polar.

An insulator may be positioned between the closed portion and the current collector plate.

The terminal may be coupled to the terminal coupling portion of the current collector plate through the insulator.

A battery pack may include a plurality of batteries and a pack housing accommodating the batteries.

The battery pack may be mounted in a vehicle.

According to an aspect of the present disclosure, it is possible to dissipate external impacts and/or vibrations without concentration on a specific location when the impacts and/or vibrations are applied while the battery is in use, thereby preventing damage from occurring at a coupled part between components.

Meanwhile, according to another aspect of the present disclosure, the current collector plate itself can perform a current interrupt function without additionally installing a current interrupt member to interrupt an electric current quickly when an overcurrent occurs due to a short circuit, thereby ensuring safety of the battery while in use.

Additionally, according to another aspect of the present disclosure, since the connection pathway from the terminal coupling portion to the tab coupling portion of the current collector plate starts from the terminal coupling portion, goes through the connection portion extended more outwards in the radial direction than the tab coupling portion and the edge portion extended in the circumferential direction, and comes back to the tab coupling portion extended inwards in the radial direction again, the shape of the current collector plate covers the entire electrode tab of the electrode assembly to flexibly respond to impacts and vibration and prevent the current collector plate from moving up and down, allowing the current collector plate to keep pressing down the electrode tabs of the electrode assembly, thereby preventing deformation of the electrode tab caused by deformation of the current collector plate.

Additionally, according to the present disclosure, even though the terminal coupling portion and the tab coupling portion are relatively subjected to an external force or vibration in the axial direction or the radial direction, since the connection portion is linearly extended in the radial direction, it is possible to prevent torsion stress from acting on the coupled part of the terminal coupling portion and the tab coupling portion, thereby preventing separation at the coupled part.

However, the technical effect that can be obtained through the present disclosure is not limited to the above-described effect, and these and other effects will be clearly understood by those skilled in the art from the following description.

These and other effects of the present disclosure will be described together with the detailed description of the embodiments of the present disclosure.

The above-described objectives, features and advantages will be described in detail with reference to the accompanying drawings, and accordingly, those skilled in the art will easily practice the technical aspect of the present disclosure. In describing the present disclosure, when it is determined that a certain detailed description of relevant known technology may make the subject matter of the present disclosure unnecessarily obscure, the detailed description is omitted. Hereinafter, an exemplary embodiment according to the present disclosure will be described in detail with reference to the accompanying drawings. In the drawings, identical reference numerals are used to indicate identical or similar elements.

The terms "first", "second" and the like are used to describe various elements, and these elements are not limited by the terms. These terms are used to distinguish one element from another, and unless the context clearly indicates otherwise, a first element may be a second element.

In the specification, unless the context clearly indicates otherwise, each element may be singular or plural.

Hereinafter, it will be understood that an element is referred to as being "above (or under)" or "on (or below)" another, it can be on an upper surface (or a lower surface) of the other element and intervening elements may be present between the element and the other element on (or below) the element.

Additionally, it will be further understood that when an element is referred to as being "connected to", "coupled to" or "joined to" another element, it can be directly connected or joined to the other element, or intervening elements may be present, or each element may be "connected to", "coupled to" or "joined to" each other through another element.

As used herein, the singular forms include the plural forms as well unless the context clearly indicates otherwise. It should be interpreted that the terms "comprises" or "comprising", when used in this specification, specifies the presence of stated elements or steps, but does not preclude the presence or addition of one or more other elements or steps.

Additionally, the singular forms as used herein include the plural forms as well unless the context clearly indicates otherwise. It should be interpreted that the terms "comprises" or "comprising", when used in this specification, specifies the presence of stated elements or steps, but does not preclude the presence or addition of one or more other elements or steps.

In the specification, unless the context clearly indicates otherwise, "A and/or B" represents either A or B or both, and "C to D" represents C or more and D or less.

In describing an embodiment below, a hightwise direction in which a battery is extended is referred to as a heightwise direction or an axial direction Z, and a direction around the axial direction is referred to as a circumferential direction. Here, a direction in which an open portion is formed in the heightwise direction of the battery is referred to as a downward direction, and a direction in which a closed portion is formed is referred to as an upward direction.

Furthermore, a direction extended in a radial direction from the center of the battery is referred to as a radial direction X, Y, and a direction that faces outwards in the radial direction is referred to as a centrifugal direction and a direction that faces inwards in the radial direction is referred to as a centripetal direction.

Referring to <FIG>, a battery <NUM> according to the present disclosure includes an electrode assembly <NUM> and a cylindrical battery housing <NUM> accommodating the electrode assembly <NUM>.

The battery housing <NUM> has a closed portion on top (one end in the axial direction) and an open portion on bottom (the other end in the axial direction).

A terminal <NUM> is installed at the center of the closed portion.

The open portion is closed by a cap plate <NUM>.

The electrode assembly <NUM> includes a first electrode tab <NUM> and a second electrode tab <NUM>.

The first electrode tab <NUM> is electrically connected to the terminal <NUM>, and the second electrode tab <NUM> is electrically connected to the battery housing <NUM>.

The terminal <NUM> and the battery housing <NUM> are insulated from each other.

The present disclosure provides a current collector plate <NUM> between the first electrode tab <NUM> of the electrode assembly <NUM> and the terminal <NUM> to electrically connect them.

The current collector plate <NUM> may be positioned between the closed portion of the battery housing <NUM> and the electrode assembly <NUM>.

Referring to <FIG>, the current collector plate <NUM> includes: an edge portion <NUM> extended in the circumferential direction to define a space inside; a tab coupling portion <NUM> extended from the edge portion <NUM> in the centripetal direction and coupled to the first electrode tab <NUM>; and a terminal coupling portion <NUM> disposed at the centripetal position relative to the edge portion <NUM>, spaced apart from the tab coupling portion <NUM>, and connected to the tab coupling portion <NUM> through the edge portion <NUM>.

Among the terminal coupling portion <NUM>, the edge portion <NUM> and the tab coupling portion <NUM>, the edge portion <NUM> may be disposed at the outermost centrifugal position and the terminal coupling portion <NUM> may be disposed at the innermost centripetal position.

The edge portion <NUM> may have a rim shape having a central hollow.

The edge portion <NUM> may have a substantially circular flat ring shape.

A plurality of tab coupling portions <NUM> may be arranged along the circumferential direction of the edge portion <NUM>.

The extended length of each of the plurality of tab coupling portions <NUM> may correspond to each other.

The plurality of tab coupling portions <NUM> may be arranged at equal intervals along the circumferential direction of the edge portion <NUM>.

The tab coupling portion <NUM> may be extended from the inner circumference of the edge portion <NUM> in the centripetal direction.

A part of the tab coupling portion <NUM> facing the terminal coupling portion <NUM> may have a tapered shape toward the terminal coupling portion <NUM>. The tapered shape increases the open area of the current collector plate <NUM> by reducing the unnecessary area of the tab coupling portion <NUM>.

On the basis of an imaginary line (see the dashed line in <FIG>) connecting the connected parts of two adjacent tab coupling portions <NUM> in the circumferential direction and the edge portion <NUM> in the shape of a straight line, the edge portion <NUM> (see the double dashed line in <FIG>) between the two adjacent tab coupling portions <NUM> may be disposed at the more centrifugal position than the imaginary line (see the dashed line in <FIG>).

The terminal coupling portion <NUM> may be connected to the edge portion <NUM> between the two adjacent tab coupling portions <NUM> in the circumferential direction.

The terminal coupling portion <NUM> may be disposed at or near the center of the centripetal area relative to the edge portion <NUM>, and the edge portion <NUM> and the terminal coupling portion <NUM> may be connected by a connection portion <NUM>.

The connection portion <NUM> may be extended more outwards in the radial direction than the imaginary line (see the dashed line in <FIG>) connecting the connection portions of the two adjacent tab coupling portions <NUM> in the circumferential direction and the edge portion <NUM> in the shape of a straight line (see the single dashed line in <FIG>).

The terminal coupling portion <NUM> may be surrounded by the plurality of tab coupling portions <NUM>.

The plurality of tab coupling portions <NUM> may be spaced apart from the terminal coupling portion <NUM> in the radial direction, and may be radially arranged around the terminal coupling portion <NUM>.

The connection portion <NUM> may be linearly extended in the shape of a straight line to connect the terminal coupling portion <NUM> to the edge portion <NUM>.

The connection portion <NUM> may have a straight line shape that passes through the center of the current collector plate <NUM>.

The connection portion <NUM> may be extended from the terminal coupling portion <NUM> in the radial direction and connected to the edge portion <NUM>.

The connection portion <NUM> may be substantially extended from the center of the terminal coupling portion <NUM> in the radial direction and connected to the edge portion <NUM>.

A plurality of connection portions <NUM> may be provided, and may be arranged at equal intervals along the outer circumference of the terminal coupling portion <NUM>.

The plurality of connection portions <NUM> may be arranged at equal intervals along the circumferential direction of the edge portion <NUM>.

The connection portion <NUM> may be disposed between a pair of tab coupling portions <NUM> adjacent to each other in the circumferential direction.

The connection portion <NUM> is extended through a space between the edge portion <NUM> and the terminal coupling portion <NUM> while avoiding the tab coupling portion <NUM> to electrically connect the edge portion <NUM> to the terminal coupling portion <NUM>.

The distance from the connection portion <NUM> to any one of the pair of tab coupling portions <NUM> along the circumferential direction may correspond to the distance from the connection portion <NUM> to the other one of the pair of tab coupling portions <NUM> along the circumferential direction.

The current collector plate <NUM> may have a radially symmetric structure. The radially symmetric structure refers to a symmetrical structure in which the shape of a target for measuring symmetry matches when the target is rotated at a predetermined angle. Preferably, the current collector plate <NUM> may have the radially symmetric structure by <NUM>°, <NUM>° or <NUM>° rotation. In an example, when the current collector plate <NUM> is rotated <NUM>°, the structure may match. However, the present disclosure is not limited by the angle of rotation of the radially symmetric structure.

The electrical conduction pathway from the terminal coupling portion <NUM> to the tab coupling portion <NUM> may be in an order of the terminal coupling portion <NUM>, the connection portion <NUM>, the edge portion <NUM> and the tab coupling portion <NUM>.

At least part along the extension direction of the connection portion <NUM> may have a smaller width than the tab coupling portion <NUM>.

When the terminal coupling portion <NUM> is subjected to a force in the radial direction and/or the axial direction relative to the tab coupling portion <NUM>, the edge portion <NUM> and/or the connection portion <NUM> between the two adjacent tab coupling portions <NUM> may absorb the force as it deforms. In this instance, torsion stress does not occur at the coupled part of the terminal coupling portion <NUM> and the tab coupling portion <NUM>.

The connection portion <NUM> may include a tapered portion 44a having a gradual reduction in width along a direction from the inner circumferential surface of the edge portion <NUM> toward the terminal coupling portion <NUM>.

Referring to <FIG> and <FIG>, the connection portion <NUM> may include a notching portion N having a local reduction in cross sectional area along the extension direction.

The notching portion N may be disposed closer to the edge portion <NUM> than the terminal coupling portion <NUM>.

Referring back to <FIG>, the current collector plate <NUM> may be used in the battery <NUM>.

The battery <NUM> including the current collector plate <NUM> may include the battery housing <NUM> accommodating the electrode assembly <NUM>.

The battery housing <NUM> may have the closed portion on one side in the axial direction and the open portion on the other side.

The electrode assembly <NUM> including the first electrode tab <NUM> and the second electrode tab <NUM> may be inserted through the open portion.

The first electrode tab <NUM> and the second electrode tab <NUM> of the electrode assembly <NUM> may be positioned on one side and the other side in the axial direction respectively.

When the electrode assembly <NUM> is received in the battery housing <NUM>, the first electrode tab <NUM> may face the closed portion, and the second electrode tab <NUM> may face the open portion.

The terminal <NUM> may be disposed at the closed portion.

The terminal <NUM> may pass through the closed portion.

The first electrode tab <NUM> may be electrically connected to the terminal <NUM>.

The first electrode tab <NUM> and the terminal <NUM> may be electrically connected through the current collector plate <NUM>.

The first electrode tab <NUM> may be coupled to the tab coupling portion <NUM> of the current collector plate <NUM>, and the terminal <NUM> may be coupled to the terminal coupling portion <NUM> of the current collector plate <NUM>.

The second electrode tab <NUM> may be electrically connected to the battery housing <NUM>.

The terminal coupling portion <NUM> of the current collector plate <NUM> may be disposed at a position corresponding to a hole at the winding center C of the electrode assembly <NUM>.

As shown in <FIG>, the end of the first electrode tab <NUM> may be bent in the radial direction.

The first electrode tab <NUM> may be bent in the centripetal direction or the centrifugal direction.

The tab coupling portion <NUM> of the current collector plate <NUM> may be coupled to the surface of the bent first electrode tab <NUM>.

The connection portion <NUM> may face and contact the surface of the bent first electrode tab <NUM>.

The edge portion <NUM> may face and contact the surface of the bent first electrode tab <NUM>.

The open portion of the battery housing <NUM> may be closed by the cap plate <NUM>.

The cap plate <NUM> may not be electrically connected to the first electrode tab <NUM> and the second electrode tab <NUM> of the electrode assembly <NUM>. Accordingly, the cap plate <NUM> may be non-polar.

An insulator <NUM> may be positioned between the closed portion and the current collector plate <NUM>.

The terminal <NUM> may be coupled to the terminal coupling portion <NUM> of the current collector plate <NUM> through the insulator <NUM>.

As shown in <FIG>, a battery pack <NUM> may include a plurality of batteries <NUM> and a pack housing <NUM> accommodating the batteries <NUM>.

Additionally, as shown in <FIG>, the battery pack <NUM> may be mounted in a vehicle <NUM>.

Referring back to <FIG> and <FIG>, the battery <NUM> according to an embodiment of the present disclosure includes the electrode assembly <NUM>, the battery housing <NUM>, the cap plate <NUM>, the current collector (the first current collector) <NUM> and the terminal <NUM>. In addition to the above-described components, the battery <NUM> may further include a sealing gasket G1 and/or an insulation gasket G2 and/or the insulator <NUM> and/or a second current collector plate <NUM>.

The electrode assembly <NUM> includes a first electrode having a first polarity, a second electrode having a second polarity and a separator between the first electrode and the second electrode. The first electrode corresponds to a positive or negative electrode, and the second electrode corresponds to an electrode having the opposite polarity to the first electrode.

The electrode assembly <NUM> may have, for example, a jelly-roll shape. That is, the electrode assembly <NUM> may be made by winding a stack around the winding center C, the stack formed by stacking the first electrode, the separator and the second electrode at least once in a sequential order. In this case, there may be an additional separator on the outer circumferential surface of the electrode assembly <NUM> for the insulation from the battery housing <NUM>.

The first electrode includes a first electrode current collector and a first electrode active material layer coated on one or two surfaces of the first electrode current collector. The first electrode current collector has an uncoated portion not coated with the first electrode active material at one end in the widthwise direction (parallel to the Z axis). The uncoated portion acts as the first electrode tab <NUM>. The first electrode tab <NUM> is positioned at the upper part in the heightwise direction (parallel to the Z axis) of the electrode assembly <NUM> received in the battery housing <NUM>.

The second electrode includes a second electrode current collector and a second electrode active material layer coated on one or two surfaces of the second electrode current collector. The second electrode current collector has an uncoated portion not coated with the second electrode active material at the other end in the widthwise direction (parallel to the Z axis). The uncoated portion acts as the second electrode tab <NUM>. The second electrode tab <NUM> is positioned at the lower part in the heightwise direction (parallel to the Z axis) of the electrode assembly <NUM> received in the battery housing <NUM>.

That is, the first electrode tab <NUM> and the second electrode tab <NUM> are extended in opposite directions along the widthwise direction of the electrode assembly <NUM>, i.e., the heightwise direction of the battery <NUM> (parallel to the Z axis). The first electrode tab <NUM> is extended toward the closed portion of the battery housing <NUM>, and the second electrode tab <NUM> is extended toward the open portion of the battery housing <NUM>.

In the present disclosure, the positive electrode active material coated on the positive electrode plate and the negative electrode active material coated on the negative electrode plate may include any type of active material known in the technical field.

In an example, the positive electrode active material may include an alkali metal compound represented by formula A[AxMy]O<NUM>+z (A includes at least one of Li, Na or K; M includes at least one selected from Ni, Co, Mn, Ca, Mg, Al, Ti, Si, Fe, Mo, V, Zr, Zn, Cu, Al, Mo, Sc, Zr, Ru, and Cr; x ≥ <NUM>, <NUM> ≤ x+y ≤<NUM>, -<NUM> ≤ z ≤ <NUM>; the stoichiometric coefficients x, y and z are selected to keep the compound electrically neutral).

In another example, the positive electrode active material may be an alkali metal compound xLiM<NUM>O<NUM>-(<NUM>-x)Li<NUM>M<NUM>O<NUM> (M<NUM> includes at least one element having an average trivalent oxidation state; M<NUM> includes at least one element having an average tetravalent oxidation state; <NUM>≤x≤<NUM>) disclosed by <CIT> and <CIT>.

In still another example, the positive electrode active material may be lithium metal phosphate represented by formula LiaM<NUM>xFe<NUM>-xM<NUM>yP<NUM>-yM<NUM>zO<NUM>-z (M<NUM> includes at least one selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg and Al; M<NUM> includes at least one selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, Al, As, Sb, Si, Ge, V and S; M<NUM> includes a halogen group element optionally containing F; <NUM> < a ≤<NUM>, <NUM> ≤ x ≤ <NUM>, <NUM> ≤ y < <NUM>, <NUM> ≤ z < <NUM>; the stoichiometric coefficients a, x, y and z are selected to keep the compound electrically neutral) or Li<NUM>M<NUM>(PO<NUM>)<NUM> [M includes at least one selected from Ti, Si, Mn, Fe, Co, V, Cr, Mo, Ni, Al, Mg and Al].

Preferably, the positive electrode active material may include primary particles and/or secondary particles formed by agglomeration of the primary particles.

In an example, the negative electrode active material may include a carbon material, a lithium metal or a lithium metal compound, silicon or a silicon compound, tin or a tin compound. Metal oxide having the potential of less than 2V such as TiO<NUM> and SnO<NUM> may be used for the negative electrode active material. The carbon material may include a low crystalline carbon, a high crystalline carbon or the like.

The separator may include, for example, a porous polymer film made of a polyolefin-based polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene/butene copolymer, an ethylene/hexene copolymer and an ethylene/methacrylate copolymer, used singly or in stack. In another example, the separator may include a commonly used porous nonwoven fabric, for example, a nonwoven fabric made of high melting point glass fibers and polyethylene terephthalate fibers.

The separator may include a coating layer of inorganic particles on at least one surface. Additionally, the separator itself may be formed of a coating layer of inorganic particles. The particles that form the coating layer may be bonded with a binder such that there is interstitial volume between adjacent particles.

The inorganic particles may include inorganics having the dielectric constant of <NUM> or more. Non-limiting examples of the inorganic particles may include at least one material selected from the group consisting of Pb(Zr,Ti)O<NUM> (PZT), Pb<NUM>-xLaxZf<NUM>-yTiyO<NUM> (PLZT), PB(Mg<NUM>Nb<NUM>/<NUM>)O<NUM>-PbTiO<NUM> (PMN-PT), BaTiO<NUM>, hafnia (HfO<NUM>), SrTiO<NUM>, TiO<NUM>, Al<NUM>O<NUM>, ZrO<NUM>, SnO<NUM>, CeO<NUM>, MgO, CaO, ZnO and Y<NUM>O<NUM>.

An electrolyte may be a salt having a structure of A+B-. Here, A+ includes an alkali metal cation such as Li+, Na+, K+ or a combination thereof. B- includes at least one anion selected from the group consisting of F-, Cl-, Br-, I-, NO<NUM>-, N(CN)<NUM>-, BF<NUM>-, ClO<NUM>-, AlO<NUM>-, AlCl<NUM>-, PF<NUM>-, SbF<NUM>-, AsF<NUM>-, BF<NUM>C<NUM>O<NUM>-, BC<NUM>O<NUM>-, (CF<NUM>)<NUM>PF<NUM>-, (CF<NUM>)<NUM>PF<NUM>-, (CF<NUM>)<NUM>PF<NUM>-, (CF<NUM>)<NUM>PF-, (CF<NUM>)<NUM>P-, CF<NUM>SO<NUM>-, C<NUM>F<NUM>SO<NUM>-, CF<NUM>CF<NUM>SO<NUM>-, (CF<NUM>SO<NUM>)<NUM>N-, (FSO<NUM>)<NUM>N-, CF<NUM>CF<NUM>(CF<NUM>)<NUM>CO-, (CF<NUM>SO<NUM>)<NUM>CH-, (SF<NUM>)<NUM>C-, (CF<NUM>SO<NUM>)<NUM>C-, CF<NUM>(CF<NUM>)<NUM>SO<NUM>-, CF<NUM>CO<NUM>-, CH<NUM>CO<NUM>-, SCN- and (CF<NUM>CF<NUM>SO<NUM>)<NUM>N-.

The electrolyte may be used by dissolving in an organic solvent. The organic solvent may include at least one of propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, tetrahydrofuran, N-methyl-<NUM>-pyrrolidone (NMP), ethyl methyl carbonate (EMC) or γ-butyrolactone.

The battery housing <NUM> is an approximately cylindrical container having the open portion on the bottom, and for example, is made of a material having conductive properties such as metal. The material of the battery housing <NUM> may be, for example, aluminum. The battery housing <NUM> has the open portion at the lower end of the height and the closed portion at the upper end. The battery housing <NUM> accommodates the electrode assembly <NUM> through the open portion on the bottom and also accommodates the electrolyte.

The battery housing <NUM> is electrically connected to the electrode assembly <NUM>. For example, the battery housing <NUM> is electrically connected to the second electrode tab <NUM> of the electrode assembly <NUM>. Accordingly, the battery housing <NUM> may have the same polarity as the second electrode tab <NUM>.

Referring to <FIG> and <FIG>, the battery housing <NUM> may include a beading portion <NUM> and a crimping portion <NUM> at the lower end. The beading portion <NUM> is disposed below the electrode assembly <NUM>. The beading portion <NUM> is formed by pressing the outer circumferential surface of the battery housing <NUM> in the centripetal direction. The beading portion <NUM> may prevent the electrode assembly <NUM> having a size approximately corresponding to the width of the battery housing <NUM> from slipping through the open portion on the bottom of the battery housing <NUM>, and may act as a support on which the cap plate <NUM> is seated.

The crimping portion <NUM> is disposed below the beading portion <NUM>. The crimping portion <NUM> is extended and bent to surround the outer circumferential surface of the cap plate <NUM> below the beading portion <NUM> and part of the lower surface of the cap plate <NUM>.

However, the present disclosure does not exclude that the battery housing <NUM> does not include the beading portion <NUM> and/or the crimping portion <NUM>. In the present disclosure, when the battery housing <NUM> does not include the beading portion <NUM> and/or the crimping portion <NUM>, the fixing of the electrode assembly <NUM> and/or the fixing of the cap plate <NUM> and/or the sealing of the battery housing <NUM> may be, for example, accomplished through additional application of a component that may act as a stopper for the electrode assembly <NUM> and/or additional application of a structure on which the cap plate <NUM> may be seated and/or welding between the battery housing <NUM> and the cap plate <NUM>.

The area of the closed portion of the battery housing <NUM> that forms the upper surface may have the thickness ranging from approximately <NUM> to <NUM>, and more preferably from approximately <NUM> to <NUM>. The sidewall of the battery housing <NUM> that forms the outer circumferential surface may have the thickness ranging from approximately <NUM> to <NUM>, and more preferably from approximately <NUM> to <NUM>. According to an embodiment of the present disclosure, the battery housing <NUM> may have a plating layer. In this case, the plating layer may include, for example, nickel (Ni). The thickness of the plating layer may range from approximately <NUM> µm to <NUM> µm.

As the thickness of the battery housing <NUM> is smaller, the internal space is larger, and accordingly it is possible to manufacture the battery <NUM> with the improved energy density and high capacity. On the contrary, with the increasing thickness, it is possible to prevent the propagation of flames to the adjacent battery in an explosion test, thereby improving the safety.

As the thickness of the plating layer is smaller, it is more susceptible to corrosion, and as the thickness of the plating layer is larger, the manufacturing process complexity may increase or there is a higher likelihood that plating delamination may occur. Taking these conditions into account, it is necessary to set the optimum thickness of the battery housing <NUM> and the optimum thickness of the plating layer. Moreover, taking all the conditions into account, it is necessary to control each of the thickness of the closed portion of the battery housing <NUM> and the thickness of the sidewall.

Referring to <FIG> and <FIG>, the cap plate <NUM> may be made of, for example, a metal to ensure the strength. The cap plate <NUM> closes the open portion on the bottom of the battery housing <NUM>. That is, the cap plate <NUM> forms the lower surface of the battery <NUM>. In the battery <NUM> of the present disclosure, the cap plate <NUM> may be non-polar even when it is made of the conductive metal. The non-polar cap plate <NUM> may represent that the cap plate <NUM> is electrically insulated from the battery housing <NUM> and the terminal <NUM>. The cap plate <NUM> may be non-polar, and the material does not need to be the conductive metal.

When the battery housing <NUM> of the present disclosure includes the beading portion, the cap plate <NUM> may be seated on the beading portion <NUM> of the battery housing <NUM>. Additionally, when the battery housing <NUM> of the present disclosure includes the crimping portion <NUM>, the cap plate <NUM> is fixed by the crimping portion <NUM>. The sealing gasket G1 may be interposed between the cap plate <NUM> and the crimping portion <NUM> of the battery housing <NUM> to ensure sealability of the battery housing <NUM>. Meanwhile, as described above, the battery housing <NUM> of the present disclosure may not include the beading portion <NUM> and/or the crimping portion <NUM>, and in this case, the sealing gasket G1 may be interposed between the cap plate <NUM> and the fixing structure at the open portion of the battery housing <NUM> to ensure sealability of the battery housing <NUM>.

Referring to <FIG> and <FIG>, the cap plate <NUM> may further include a venting portion <NUM> to prevent the internal pressure from rising above a preset pressure due to gas generated in the battery housing <NUM>. The venting portion <NUM> corresponds to an area having a smaller thickness than the other areas in the cap plate <NUM>. The venting portion <NUM> is structurally weaker than any other area. Accordingly, when the internal pressure of the battery housing <NUM> rises above the predetermined level due to abnormality in the battery <NUM>, the venting portion <NUM> ruptures to force the gas generated in the battery housing <NUM> out. For example, the venting portion <NUM> may be formed by notching on any one or two surfaces of the cap plate <NUM> to partially reduce the thickness of the battery housing <NUM>.

The battery <NUM> according to an embodiment of the present disclosure has a structure in which both the positive and negative terminals exist at the upper part as described below, so the upper part structure is more complicated than the lower part structure. Accordingly, for smooth venting of gas generated in the battery housing <NUM>, the venting portion <NUM> may be formed in the cap plate <NUM> that forms the lower surface of the battery <NUM>. As shown in <FIG>, the lower end of the cap plate <NUM> is preferably disposed higher than the lower end of the battery housing <NUM>. In this case, even when the lower end of the battery housing <NUM> contacts the ground or the bottom surface of the housing for forming a module or a pack, the cap plate <NUM> does not contact the ground or the bottom surface of the housing for forming a module or a pack. Accordingly, it is possible to prevent a phenomenon in which the pressure required for the rupture of the venting portion <NUM> is different from the design pressure due to the weight of the battery <NUM>, thereby allowing for smooth rupture of the venting portion <NUM>.

Meanwhile, when the venting portion <NUM> has a closed loop shape as shown in <FIG> and <FIG>, as the distance from the center of the cap plate <NUM> to the venting portion <NUM> is longer, the venting portion <NUM> may rupture more easily. When the same venting pressure is applied, as the distance from the center of the cap plate <NUM> to the venting portion <NUM> is longer, a larger force acts on the venting portion <NUM> and the venting portion <NUM> ruptures more easily. Additionally, as the distance from the center of the cap plate <NUM> to the venting portion <NUM> is longer, it is possible to achieve more smooth discharge of venting gas. From this perspective, the venting portion <NUM> may be preferably formed along the edge of the approximately flat area extended downwards (in a downward direction on the basis of <FIG>) from the edge area of the cap plate <NUM>.

Although <FIG> shows the venting portion <NUM> continuously formed in an approximately circular shape on the cap plate <NUM>, the present disclosure is not limited thereto. The venting portion <NUM> may be discontinuously formed in an approximately circular shape on the cap plate <NUM>, and may be formed in approximately a straight line or any other shape.

Referring to <FIG>, the current collector plate (the first current collector plate) <NUM> is coupled onto the electrode assembly <NUM>. The current collector plate <NUM> is made of a metal having conductive properties, and is connected to the first electrode tab <NUM>.

Referring to <FIG>, the current collector plate <NUM> may be coupled onto a coupling surface formed by bending the end of the first electrode tab <NUM> in a direction parallel to the current collector plate <NUM>. The bending direction of the first electrode tab <NUM> may be, for example, a direction toward the winding center C of the electrode assembly <NUM>. When the first electrode tab <NUM> is bent in this way, it is possible to reduce the space occupied by the first electrode tab <NUM>, thereby improving the energy density. Additionally, it is possible to increase the coupling area between the first electrode tab <NUM> and the current collector plate <NUM>, leading to the improved bond strength and the reduced resistance.

Referring to <FIG> together with <FIG>, the current collector <NUM> includes the edge portion <NUM>, the tab coupling portion <NUM> and the terminal coupling portion <NUM>. The edge portion <NUM> may have an approximately rim shape having an empty space S at the center. Although the drawings of the present disclosure show the edge portion <NUM> having an approximately circular rim shape, the present disclosure is not limited thereto. The edge portion <NUM> may have an approximately square rim shape or any other shape.

The edge portion <NUM> may be disposed at the outermost side in the radial direction. An embodiment shows the edge portion <NUM> having a closed loop shape without discontinuity along the circumferential direction. This structure may firmly support the strength of the entire current collector plate <NUM> to prevent the welded part of the tab coupling portion <NUM> and the terminal coupling portion <NUM> as described below from being subjected to a shear force (in particular, a shear force acting in a direction parallel to the plane including the current collector plate).

However, the edge portion <NUM> does not need to have the closed loop shape, and may have the closed loop shape as a whole even though there is at least one cut-out.

The tab coupling portion <NUM> is extended inwards from the edge portion <NUM> and is coupled to the first electrode tab <NUM>. The terminal coupling portion <NUM> is disposed inside of the edge portion <NUM>, spaced apart from the tab coupling portion <NUM>. The terminal coupling portion <NUM> may be coupled to the terminal <NUM> as described below by welding. The terminal coupling portion <NUM> may be, for example, disposed at the center of the space inside of the edge portion <NUM>. The terminal coupling portion <NUM> may be disposed at the location corresponding to the hole at the winding center C of the electrode assembly <NUM>.

The tab coupling portion <NUM> and the terminal coupling portion <NUM> are spaced apart from each other without direct connection, and they are electrically connected by the edge portion <NUM>. As described above, the current collector plate <NUM> according to an embodiment of the present disclosure has a structure in which the tab coupling portion <NUM> and the terminal coupling portion <NUM> are not directly connected to each other and they are connected through the edge portion <NUM> disposed at the outermost centrifugal position in the radial direction, so when impacts and/or vibrations occur in the battery <NUM>, it is possible to dissipate the impacts applied to the coupled part between the tab coupling portion <NUM> and the first electrode tab <NUM> and the coupled part between the terminal coupling portion <NUM> and the terminal <NUM>. Accordingly, the current collector plate <NUM> of the present disclosure may minimize or prevent damage to the welded part due to external impacts. The current collector plate <NUM> of the present disclosure has a structure in which stress may concentrate on the connected part of the edge portion <NUM> and the terminal coupling portion <NUM> when external impacts are applied, and since a welded part for coupling between components is not formed in the connected part, it is possible to prevent product defects caused by damage to the welded part due to external impacts.

The current collector plate <NUM> may further include the connection portion <NUM> extended inwards from the edge portion <NUM> and connected to the terminal coupling portion <NUM>. At least part of the connection portion <NUM> may have a smaller width than the tab coupling portion <NUM>. In this case, when the electrical resistance at the connection portion <NUM> increases and the current flows through the connection portion <NUM>, higher resistance occurs, so when an overcurrent occurs, a part of the connection portion <NUM> ruptures to interrupt the overcurrent. The width of the connection portion <NUM> may be adjusted to a suitable level considering the overcurrent interrupt function.

The connection portion <NUM> may include the tapered portion 44a having a gradual reduction in width along a direction from the inner surface of the edge portion <NUM> toward the terminal coupling portion <NUM>. With the tapered portion 44a, it is possible to improve the strength of the component at the connected part of the connection portion <NUM> and the edge portion <NUM>. Furthermore, the tapered portion 44a may act as an area that covers the bent electrode tab.

There may be a plurality of tab coupling portions <NUM>. The plurality of tab coupling portions <NUM> may be arranged at equal intervals along the extension direction of the edge portion <NUM>. The extended length of each of the plurality of tab coupling portions <NUM> may be equal. The terminal coupling portion <NUM> may be surrounded by the plurality of tab coupling portions <NUM>. The connection portion <NUM> may be disposed between a pair of adjacent tab coupling portions <NUM>. In this case, the distance from the connection portion <NUM> to any one of the pair of tab coupling portions <NUM> along the extension direction of the edge portion <NUM> may be equal to the distance from the connection portion <NUM> to the other one of the pair of tab coupling portions <NUM> along the extension direction of the edge portion <NUM>.

There may be a plurality of connection portions <NUM>. Each of the plurality of connection portions <NUM> may be positioned between the pair of adjacent tab coupling portions <NUM>. The plurality of connection portions <NUM> may be arranged at equal intervals along the extension direction of the edge portion <NUM>.

As described above, in the case that the plurality of tab coupling portions <NUM> and/or the plurality of connection portions <NUM> are provided, when the distance between the tab coupling portions <NUM> and/or the distance between the connection portions <NUM> and/or the distance between the tab coupling portion <NUM> and the connection portion <NUM> is constant, a flow of current from the tab coupling portion <NUM> to the connection portion <NUM> or a flow of current from the connection portion <NUM> to the tab coupling portion <NUM> may be smoothly formed.

The connection portion <NUM> may be extended from the center of the current collector plate <NUM> in the radial direction, and may be linearly extended. Accordingly, it is possible to reduce the electrical conduction distance, and even when a compression force or a tensile force is applied to any one connection portion <NUM> in the extension direction, it is possible to prevent any change in the shape of the connection portion <NUM> and prevent deformation of the whole shape of the current collector plate <NUM>. Accordingly, it is possible to prevent the current collector plate <NUM> from moving so much, thereby preventing the first electrode tab <NUM> compressed by the current collector plate <NUM> from moving or deforming by the movement of the current collector plate <NUM>.

Furthermore, due to the structure in which the plurality of connection portions <NUM> having a straight line shape is connected by the terminal coupling portion <NUM>, when the connection portion <NUM> on any one side of the terminal coupling portion <NUM> is subjected to an external force, the connection portion <NUM> connected to the other side functions to support it. Furthermore, even though the tab coupling portion <NUM> and the terminal coupling portion <NUM> of the current collector plate <NUM> are subjected to forces in different axial directions, torsion stress do not occur at the tab coupling portion <NUM> and the terminal coupling portion <NUM>, thereby protecting the welding part.

The confined part of the current collector plate <NUM> to the other component by welding is the terminal coupling portion <NUM> and the tab coupling portion <NUM>. Additionally, they are connected by the edge portion <NUM>. The terminal coupling portion <NUM> is disposed at the center in the radial direction, the edge portion <NUM> is disposed at the edge in the radial direction, and the tab coupling portion <NUM> is disposed between the center and the edge in the radial direction.

Accordingly, when the terminal coupling portion <NUM> is subjected to a force in the radial direction or the axial direction relative to the tab coupling portion <NUM>, the connection portion <NUM> having a linear shape may transmit the force to the edge portion <NUM>, and the edge portion <NUM> extended in the circumferential direction may respond to the external force as it flexibly deforms.

Referring to <FIG> and <FIG>, the connection portion <NUM> may include the notching portion N having a local reduction in cross sectional area along the extension direction of the connection portion <NUM>. The reduction in cross sectional area may be accomplished by reducing the width and/or thickness of the connection portion <NUM>. With the notching portion N, it is possible to interrupt the current quickly when an overcurrent occurs as the electrical resistance at the area having the notching portion N increases.

When the connection portion <NUM> includes the tapered portion 44a, the notching portion N may be disposed closer to the tapered portion 44a than the terminal coupling portion <NUM>. In this case, due to the structure of the edge portion 44a having a gradual reduction in width, when the notching portion N is disposed at an area adjacent to a high heat generation area, it is possible to interrupt the overcurrent more quickly.

Referring to <FIG> and <FIG>, the terminal <NUM> is made of a metal having conductive properties, and is coupled to the terminal coupling portion <NUM> of the current collector plate (the first current collector plate) <NUM>. The terminal <NUM> may pass through the closed portion opposite to the open portion of the battery housing <NUM>. When the battery <NUM> of the present disclosure includes the insulator <NUM>, the terminal <NUM> is coupled to the terminal coupling portion <NUM> of the current collector plate <NUM> through the insulator <NUM>.

The terminal <NUM> is electrically connected to the first electrode tab <NUM> of the electrode assembly <NUM> through the current collector plate <NUM>, and thus has the first polarity. Accordingly, the terminal <NUM> may act as the first electrode terminal of the battery <NUM> of the present disclosure. Additionally, in the battery <NUM> of the present disclosure, the approximately flat surface of the closed portion of the battery housing <NUM> having the second polarity may act as the second electrode terminal 20a. Referring to <FIG>, a busbar B is connected to each of the first electrode terminal <NUM> and the second electrode terminal 20a of the battery <NUM> of the present disclosure. In each of the first electrode terminal <NUM> and the second electrode terminal 20a, to ensure a sufficient coupling area with the busbar B, the width D1 of the exposed area of the first electrode terminal <NUM> through the battery housing <NUM> may be set to the range of approximately <NUM>% to <NUM>% of the width D2 of the second electrode terminal 20a, i.e., the upper surface of the battery housing <NUM>.

When the terminal <NUM> has the first polarity, the terminal <NUM> is electrically insulated from the battery housing <NUM> having the second polarity. The insulation between the terminal <NUM> and the battery housing <NUM> may be accomplished by various methods. For example, the insulation may be accomplished by placing the insulation gasket G2 between the terminal <NUM> and the battery housing <NUM>. The insulation gasket G2 may be made of, for example, a resin material having insulating properties.

Alternatively, the insulation may be accomplished by forming an insulating coating layer at a part of the terminal <NUM>. Alternatively, the terminal <NUM> may be structurally firmly fixed to prevent the contact between the terminal <NUM> and the battery housing <NUM>. Alternatively, two or more of the above-described methods may be applied together.

Referring to <FIG> and <FIG> together with <FIG>, the insulator <NUM> may be disposed between the current collector plate (the first current collector plate) <NUM> and the inner surface of the battery housing <NUM>. The insulator <NUM> prevents the contact between the current collector plate <NUM> and the battery housing <NUM>. The insulator <NUM> may be positioned between the upper end of the outer circumferential surface of the electrode assembly <NUM> and the inner surface of the battery housing <NUM>. This is to prevent the contact between the first electrode tab <NUM> extended toward the closed portion of the battery housing <NUM> and the inner circumferential surface of the battery housing <NUM>.

When the battery <NUM> of the present disclosure includes the insulator <NUM>, the terminal <NUM> is coupled to the current collector plate <NUM> through the insulator <NUM>. To allow the terminal <NUM> to pass through, the insulator <NUM> may have an opening at a location corresponding to the terminal coupling portion <NUM> of the current collector plate <NUM>.

Referring to <FIG>, the current collector plate (the second current collector plate) <NUM> is coupled to a lower portion of the electrode assembly <NUM>. The current collector plate <NUM> is made of a metal having conductive properties and coupled to the second electrode tab <NUM>. Additionally, the current collector plate <NUM> is electrically connected to the battery housing <NUM>. The edge area of the current collector plate <NUM> may be fixed between the inner surface of the battery housing <NUM> and the sealing gasket G1. In this case, the current collector plate <NUM> may be welded onto a seating surface formed by the beading portion <NUM> of the battery housing <NUM>.

Referring to <FIG>, the current collector plate <NUM> may be coupled onto the coupling surface formed by bending the end of the second electrode tab <NUM> in the direction parallel to the current collector plate <NUM>. The bending direction of the second electrode tab <NUM> may be, for example, a direction toward the winding center C of the electrode assembly <NUM>. When the second electrode tab <NUM> is bent in this way, it is possible to reduce the space occupied by the second electrode tab <NUM>, thereby improving the energy density. Additionally, it is possible to improve the bonding strength between the second electrode tab <NUM> and the current collector plate <NUM> and reduce the resistance.

Meanwhile, in the present disclosure, each of the first electrode tab <NUM> and the second electrode tab <NUM> may a plurality of segments spaced apart from each other by the cutout grooves formed regularly in the uncoated portion along the winding direction of the electrode. The plurality of segments may be exposed outside of the separator along the winding axis direction. The plurality of segments is arranged to be overlapped along the radial direction of the electrode assembly to form a plurality of segment alignments spaced apart in the circumferential direction. Additionally, the segments included in each segment alignment may be bent along the radial direction to form a bent surface region.

In an embodiment, the tab coupling portion <NUM> of the current collector plate <NUM> may be coupled to the bent surface region of the segment alignments, and the connection portion <NUM> of the current collector plate <NUM> may be positioned between the segment alignments spaced apart from each other in the circumferential direction.

<FIG> is an exemplary plane view showing the electrode structure including the plurality of segments to form the plurality of segment alignments along the circumferential direction of the electrode assembly.

Referring to <FIG>, an electrode <NUM> of an embodiment includes a sheet-shaped current collector <NUM> and an active material layer <NUM>. The current collector <NUM> may include a metal foil. The metal foil may be a metal having conductive properties, for example, aluminum or copper. The current collector <NUM> may be appropriately selected according to the polarity of the electrode <NUM>. The metal foil may be replaced with a metal mesh. The metal foil may have a structure in which a metal film is coated on two surfaces of a substrate of an insulating film. The active material layer <NUM> is formed on at least one surface of the current collector <NUM>. The active material layer <NUM> is formed along the winding direction X. The electrode <NUM> includes an uncoated portion <NUM> at the long side end in the winding direction X. The uncoated portion <NUM> is a part of the current collector <NUM> not coated with the active material. In the electrode <NUM>, the area of the current collector <NUM> having the active material layer <NUM> may be referred to as an active material portion.

In the electrode <NUM>, the width in a direction following the short side of the current collector <NUM> may be <NUM> to <NUM>, and the length in a direction following the long side of the current collector <NUM> may be <NUM> to <NUM>. Accordingly, a ratio of the short side of the electrode <NUM> to the long side may be <NUM>% to <NUM>%. The ratio is much smaller than <NUM>% to <NUM>% of that of an electrode used in a cylindrical battery having the form factor of <NUM> or <NUM>.

Preferably, an insulating coating layer <NUM> may be formed at the boundary of the active material layer <NUM> and the uncoated portion <NUM>. At least part of the insulating coating layer <NUM> overlaps the boundary of the active material layer <NUM> and the uncoated portion <NUM>. The insulating coating layer <NUM> prevents a short circuit between two electrodes having the opposite polarities with the separator interposed therebetween. The insulating coating layer <NUM> is <NUM> to <NUM> in width to cover the boundary of the active material layer <NUM> and the uncoated portion <NUM>. The insulating coating layer <NUM> includes polymer resin, and may include inorganic fillers such as Al<NUM>O<NUM> or SiO<NUM>. Since the part of the current collector <NUM> covered with the insulating coating layer <NUM> is not coated with the active material layer, it may be regarded as an uncoated portion.

The uncoated portion <NUM> includes a first part B1 near a core, a second part B3 near an outer circumference and a third part B2 between the first part B1 and the second part B3. The core and the outer circumference indicate a central area and an outer circumferential surface of the electrode assembly, respectively, when the electrode <NUM> is wound as the electrode assembly.

Among the first part B1, the second part B3 and the third part B2, the third part B2 has the longest length, and occupies a majority of the length of the electrode <NUM>. The first part B1 may form multiple winding turns near the core of the electrode assembly. The second part B3 may form at least one winding turn near the outer circumference of the electrode assembly.

The third part B2 includes the plurality of segments <NUM>. The plurality of segments <NUM> is used for electrical connection to the current collector plate <NUM>, and thus corresponds to the first electrode tab <NUM>. Preferably, the segments <NUM> may have a rectangular shape. Alternatively, the segments <NUM> may have a trapezoidal shape, a parallelogram shape or a semi-circular shape. Many modifications may be made to the geometric shape of the segments <NUM>.

The plurality of segments <NUM> may be notched by a laser. Alternatively, the segments <NUM> may be formed by the known metal foil cutting process, for example, ultrasonic cutting or punching. In the winding direction X, the distance (pitch) between the segments <NUM> may increase as it goes from the core to the outer circumference.

The cutout groove <NUM> is positioned between the adjacent segments <NUM> in the winding direction X. The cutout groove <NUM> is formed in the notching process of the segments <NUM>. The cutout groove <NUM> includes a flat bottom portion 86a, a round portion 86b adjacent to the flat bottom 86a and a side portion 86c of the segment <NUM>. Here, the round portion 86c may mitigate the stress when the segment <NUM> is bent, thereby preventing cracking at the lower end of the segment <NUM>.

To prevent damage to the active material layer <NUM> and/or the insulating coating layer <NUM> when bending the segment <NUM>, it is desirable to form a predetermined gap between the bottom portion 86a of the cutout groove <NUM> and the active material layer <NUM>. It is because when the segment <NUM> is bent, stress concentrates on or near the bottom portion 86a of the cutout groove <NUM>. The gap is <NUM> to <NUM>, and preferably <NUM> to <NUM>. When the gap is adjusted to the corresponding numerical range, it is possible to prevent stress-induced damage to the active material layer <NUM> and/or the insulating coating layer <NUM> near the lower end of the cutout groove <NUM> when bending the segment <NUM>. Additionally, the gap may prevent damage to the active material layer <NUM> and/or the insulating coating layer <NUM> caused by the tolerance in the notching or cutting process of the segment <NUM>. The lower end of the cutout groove <NUM> and the insulating coating layer <NUM> may be spaced apart by <NUM> to <NUM>. When the electrode <NUM> is wound, the end in the winding axis Y direction of the insulating coating layer <NUM> may be disposed in the range of -<NUM> to <NUM> along the winding axis direction on the basis of the end of the separator. The insulating coating layer <NUM> may prevent a short circuit between two electrodes having the opposite polarities with the separator interposed therebetween and support the location at which the segment <NUM> is bent. To improve the short circuit prevention effect between two electrodes, the insulating coating layer <NUM> may be exposed outside of the separator. Additionally, to maximize the short circuit prevention effect between two electrodes, the insulating coating layer <NUM> may increase in width to place the end in the winding axis Y direction of the insulating coating layer <NUM> at a higher position than the bottom portion 86a of the cutout groove <NUM>. In an embodiment, the end in the winding axis direction of the insulating coating layer <NUM> may be disposed in the range of -<NUM> to +<NUM> on the basis of the bottom portion 86a of the cutout groove <NUM>.

<FIG> is a top view of the electrode assembly JR manufactured by winding the positive electrode and the negative electrode having the structure of the electrode <NUM> shown in <FIG> together with the separator, <FIG> is a partial perspective view showing the upper part of the electrode assembly JR, and <FIG> is a partial cross-sectional view taken along the line A-A ' of <FIG>. The upper part of the electrode assembly JR shown in the drawings is the positive electrode side.

Referring to <FIG>, the plurality of segments <NUM> protrudes from the separator and protrudes in the winding axis direction Y. Additionally, the plurality of segments <NUM> is radially arranged around the core C of the electrode assembly JR to form a segment alignment <NUM>. The segment alignment <NUM> refers to an assembly of segments <NUM> arranged such that the segments <NUM> at different winding turns overlap in the radial direction of the electrode assembly JR.

The plurality of segments <NUM> included in the segment alignment <NUM> overlap each other in the radial direction, which means that when a predetermined straight line passing through the segment alignment <NUM> from the center of the core C is drawn, all the segments <NUM> intersect the corresponding straight line.

The segment alignment <NUM> is extended to a predetermined length along the radial direction of the electrode assembly JR, and in the segment alignment <NUM>, the segments <NUM> of the winding turns adjacent to in the radial direction may have an overlap in the angle of circumference measured on the basis of the center of the core.

The number of segment alignments <NUM> may be <NUM>, <NUM> or <NUM>, and the number of segment alignments <NUM> is not limited thereto. The plurality of segment alignments <NUM> may be arranged at equal intervals in the circumferential direction. The segment alignments <NUM> may be arranged at non-equal intervals in the circumferential direction.

When the number of segment alignments <NUM> is <NUM>, the angle between the adjacent segment alignments <NUM> in the circumferential direction may be about <NUM>°. When the number of segment alignments <NUM> is <NUM>, the angle between the adjacent segment alignments <NUM> in the circumferential direction may be about <NUM>°. When the number of segment alignments <NUM> is <NUM>, the angle between the adjacent segment alignments <NUM> in the circumferential direction may be about <NUM>°.

The angle θ between the adjacent segment alignments <NUM> in the circumferential direction is defined as an angle between a side extension line of one segment alignment <NUM> and a side extension line of another segment alignment <NUM> closest to the one segment alignment <NUM> when the electrode assembly JR is viewed from the winding axis direction Y. When an imaginary line (see the single dashed line) passing through the center of the segment alignment <NUM> from the center of the core C of the electrode assembly JR is drawn, the angle θ is substantially the same as the angle of an adjacent imaginary line in the circumferential direction.

The pitch of the segments <NUM> adjacent to each other in the winding direction X increases as it goes from the core to the outer circumference in the winding direction X of the electrode assembly JR, but may be determined according to a preset rule to form the segment alignment <NUM> in the radial direction of the electrode assembly JR. The pitch of the segments <NUM> substantially corresponds to the width of the cutout groove <NUM> in the winding direction.

An electrolyte impregnation portion <NUM> is formed between the adjacent segment alignments <NUM> in the circumferential direction of the electrode assembly JR. The electrolyte impregnation portion <NUM> is formed by winding the uncoated portion <NUM> having the cutout groove <NUM>.

As shown in <FIG>, the electrolyte impregnation portion <NUM> is a region in which the electrolyte EL may primarily impregnate, and its height is lower than the height of the segment alignment <NUM> in the winding axis direction Y. The electrolyte impregnation portion <NUM> does not have any segment <NUM> protruding from the separator Se. Additionally, in the electrolyte impregnation portion <NUM>, the end of the active material layer a1 of the positive electrode E1 and the end of the active material layer a2 of the negative electrode E2 are spaced apart by a predetermined distance more downwards than the end of the separator Se between the separators Se adjacent to each other in the radial direction of the electrode assembly JR. Accordingly, the insulation between the positive electrode E1 and the negative electrode E2 may be maintained. In an embodiment, the predetermined distance may be <NUM> to <NUM>. The insulating coating layer <NUM> may be formed in at least one of the end of the positive electrode E1 and the end of the negative electrode E2. The end of the positive electrode E1 may include a sliding portion having a gradual reduction in thickness of the active material layer a1. The arrangement structure of the electrode and the separator shown in <FIG> may be applied to the lower part of the electrode assembly JR. Preferably, at the lower part of the electrode assembly JR, the insulating coating layer <NUM> and the sliding portion may be formed at the end of the negative electrode E2.

The electrolyte EL may be impregnated into the electrode assembly JR while in direct contact with the positive electrode E1 and the negative electrode E2 through the gap between the ends of the separators Se. Specifically, the electrolyte EL loaded on the electrode assembly JR contacts the end of the positive electrode E1 and the end of the negative electrode E2 as well as the end of the separator Se at the same time and permeates into the electrode assembly JR fast. Accordingly, it is possible to remarkably improve the electrolyte wettability (rate and uniformity).

Preferably, the height H of the segment <NUM> may be substantially equal in the radial direction of the electrode assembly JR. In an example, the height of the segment <NUM> may be <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>. Alternatively, the height H of the segment <NUM> may increase stepwise as it goes from the core of the electrode assembly JR to the outer circumference. In an example, the height of the segment <NUM> may increase stepwise in the range of <NUM> to <NUM>. In an example, when the diameter of the core of the electrode assembly JR is <NUM>, the height of the segment <NUM> may increase from <NUM> to <NUM> by <NUM> in the radial range of <NUM> to <NUM>. When the height H of the segment <NUM> increases stepwise, it is possible to increase the number of stacks of the segments <NUM> in the bent surface region of the segments <NUM> and increase the length of the area in which the number of stacks is uniform in the radial direction of the electrode assembly JR.

The width W of the segment <NUM> is preferably substantially the same or larger than the width of the tab coupling portion <NUM> of the current collector plate <NUM>. The width W of the segment <NUM> may be, for example, appropriately selected in the range of <NUM> to <NUM>.

Referring to <FIG> and <FIG>, the location <NUM> at which the segment <NUM> is bent may be set to a line passing through the bottom portion 86a of the cutout groove <NUM> or a location spaced a predetermined distance apart upwards from the line. When the segment <NUM> is bent toward the core at a predetermined distance apart from the lower end of the cutout groove <NUM>, it is easier to arrange the segments to be overlapped in the radial direction. When the segments <NUM> are bent, the outer segment on the basis of the center of the core presses down the inner segment. In this instance, when the location <NUM> of bending is spaced a predetermined distance apart from the lower end of the cutout groove <NUM>, the inner segment is pressed by the outer segment in the winding axis direction, making it easier to arrange the segments <NUM> to be overlapped. The spaced apart distance of the location <NUM> of bending may be <NUM> or less, and preferably <NUM> or less.

The pitch of the segments <NUM> corresponds to the width of the cutout groove <NUM> in the winding direction X, and may be predetermined to form the segment alignment <NUM> at a preset area in the radial direction of the electrode assembly JR when winding the electrode <NUM>.

<FIG> is a diagram showing a process of coupling the current collector plate <NUM> onto the electrode assembly JR using the bent surface region F formed by bending the segments <NUM> included in the segment alignments <NUM> toward the core of the electrode assembly JR according to an embodiment of the present disclosure.

Referring to <FIG>, the segments <NUM> included in the plurality of segment alignments <NUM> may be bent toward the core of the electrode assembly JR to form the bent surface region F. The surface of the bent surface region F is approximately perpendicular to the winding axis direction of the electrode assembly JR. The bent surface region F corresponds to an area in which the segments <NUM> are stacked in multiple layers in the winding axis direction. The number of stacks of the segments <NUM> may be preferably <NUM> or more. Since the bent surface region F is formed on the segment alignment <NUM>, the segment alignment <NUM> should be understood as the structure including the bent surface region F.

<FIG> and <FIG> are top views showing the current collector plate <NUM> according to an embodiment of the present disclosure welded onto the electrode assembly JR.

Referring to <FIG> and <FIG>, each tab coupling portion <NUM> included in the current collector plate <NUM> may be coupled to the bent surface region F on the corresponding segment alignment <NUM> through welding.

Since the bent surface region F is flat and wider than the tab coupling portion <NUM>, the tab coupling portion <NUM> may be easily mounted and welded on the bent surface region F.

The connection portion <NUM> is positioned on the electrolyte impregnation portion <NUM> between the adjacent segment alignments <NUM> in the circumferential direction. As shown in <FIG>, in the electrolyte impregnation portion <NUM>, the end of the positive electrode E1 and the end of the negative electrode E2 are spaced the predetermined distance apart downwards from the end of the separator Se. Accordingly, the connection portion <NUM> may be also spaced apart from the end of the positive electrode E1 and the end of the negative electrode E2 and electrically insulated from the ends of the electrodes.

In <FIG> and <FIG>, the reference character W indicates a welding pattern. The welding pattern W may be at least one continuous or discontinuous linear pattern along the extension direction of the tab coupling portion <NUM>. The welding pattern W may be formed by laser welding. Alternatively, the welding pattern W may be formed by the other known welding method, for example, ultrasonic welding, resistance welding or the like.

The connection portion <NUM> is positioned on the electrolyte impregnation portion <NUM> on the basis of the winding axis direction Y. Additionally, since the location at which the segment <NUM> is bent spaced apart from the electrolyte impregnation portion <NUM> as shown in <FIG>, there is also a predetermined gap corresponding to an empty space between the bent surface region F formed by the bending of the segments <NUM> and the electrolyte impregnation portion <NUM>.

Accordingly, when the notching portion N of the connection portion <NUM> is interrupted by an overcurrent, the electrical connection of the terminal coupling portion <NUM> and the tab coupling portion <NUM> may be completely disconnected by the gap.

Meanwhile, when the bent surface region F is formed over the entire surface of the end of the electrode assembly JR, even though the notching portion N is ruptured by the overcurrent, the electrical connection of the terminal coupling portion <NUM> and the tab coupling portion <NUM> may be indirectly maintained through the bent surface region F.

Accordingly, in terms of reliable overcurrent interruption, the bent surface region F may be locally formed at only a part of the end of the electrode assembly JR by adjusting the pitch of the segments <NUM>, and the connection portion <NUM> including the notching portion N may be positioned at an area having no bent surface region F.

<FIG> is a plane view showing the structure of the electrode <NUM> according to another embodiment of the present disclosure, and <FIG> is a top view showing the structure of the segment alignment <NUM> on the electrode assembly in which the structure of the electrode <NUM> of <FIG> is applied to the positive electrode and the negative electrode.

Referring to <FIG> and <FIG>, the electrode <NUM> according to another embodiment of the present disclosure has a structure in which segment groups <NUM> are separated by the pitch between groups. The pitch may increase gradually or stepwise along the winding direction X. The segment groups <NUM> may include at least one segment <NUM>. The shape of the segment <NUM> is rectangular. However, modification may be made to the shape of the segment <NUM>, for example, any other geometric shape such as a trapezoidal shape.

The segment groups <NUM> are arranged to be overlapped along the radial direction to form the segment alignment <NUM> when the electrode assembly is wound. The segment alignment <NUM> has an approximately fan shape. The segments <NUM> included in the segment alignment <NUM> may be bent toward the core C to form the bent surface region F. In the same way as the above-described embodiment, the tab coupling portion <NUM> of the current collector plate <NUM> may be welded to the bent surface region F of the segment alignment <NUM>. Additionally, the connection portion <NUM> of the current collector plate <NUM> may be positioned on the electrolyte impregnation portion <NUM> between the adjacent segment alignments <NUM> in the circumferential direction.

The cylindrical battery to which the above-described embodiment of the present disclosure is applied may be, for example, a cylindrical battery having a ratio of form factor (a value obtained by dividing the diameter of the cylindrical battery by its height, i.e., defined as a ratio of diameter Φ to height H) larger than approximately <NUM>.

Here, the form factor refers to a value indicating the diameter and height of the cylindrical battery. The cylindrical battery according to an embodiment of the present disclosure may be, for example, <NUM> battery, <NUM> battery, <NUM> battery, <NUM> battery and <NUM> battery. In the numbers indicating the form factor, the former two numbers indicate the diameter of the battery, and the remaining numbers indicate the height of the battery.

The battery according to an embodiment of the present disclosure may be a battery having an approximately cylindrical shape with the diameter of approximately <NUM>, the height of approximately <NUM> and the ratio of form factor of approximately <NUM>.

The battery according to another embodiment may be a battery having an approximately cylindrical shape with the diameter of approximately <NUM>, the height of approximately <NUM> and the ratio of form factor of approximately <NUM>.

The battery according to another embodiment may be a battery having an approximately cylindrical shape with the diameter of approximately <NUM>, the height of approximately <NUM>, and the ratio of form factor of approximately <NUM>.

Conventionally, batteries having the ratio of form factor of approximately <NUM> or less have been used. That is, for example, <NUM> battery and <NUM> battery have been used. The <NUM> battery has the diameter of approximately <NUM>, the height of approximately <NUM> and the ratio of form factor of approximately <NUM>. The <NUM> battery has the diameter of approximately <NUM>, the height of approximately <NUM> and the ratio of form factor of approximately <NUM>.

Referring to <FIG>, the battery pack <NUM> according to an embodiment of the present disclosure includes a battery assembly including a plurality of batteries <NUM> according to an embodiment of the present disclosure electrically connected to each other and a pack housing <NUM> accommodating the battery assembly. In the accompanying drawings, for convenience of illustration in the drawings, the components such as the busbar for electrical connection, a cooling unit and a power terminal are omitted.

Referring to <FIG>, the vehicle <NUM> according to an embodiment of the present disclosure may be, for example, an electric vehicle, a hybrid electric vehicle or a plugin hybrid electric vehicle, and includes the battery pack <NUM> according to an embodiment of the present disclosure. The vehicle <NUM> includes a four-wheeled vehicle and a two-wheeled vehicle. The vehicle <NUM> operates using the power supplied from the battery pack <NUM> according to an embodiment of the present disclosure.

Claim 1:
A current collector plate (<NUM>) configured to be disposed between a first electrode tab (<NUM>) of an electrode assembly (<NUM>) and an exposed terminal (<NUM>) for electrical connection thereof, the current collector plate (<NUM>) comprising:
an edge portion (<NUM>) extended in a circumferential direction to define a space (S) inside;
a tab coupling portion (<NUM>) extended from an edge portion (<NUM>) in a centripetal direction and configured to be coupled to the first electrode tab (<NUM>); and
a terminal coupling portion (<NUM>) disposed at a centripetal position relative to the edge portion (<NUM>) characterized in that terminal coupling portion (<NUM>) is connected to the tab coupling portion (<NUM>) through the edge portion (<NUM>) while avoiding the tab coupling portion (<NUM>).