EP-4738523-A1 - ELECTROCHEMICAL APPARATUS AND ELECTRICAL DEVICE

EP4738523A1EP 4738523 A1EP4738523 A1EP 4738523A1EP-4738523-A1

Abstract

This application discloses an electrochemical apparatus and an electrical device. The electrochemical apparatus includes a housing and an electrode assembly. The housing includes a first housing portion and a second housing portion with opposite polarities. The electrode assembly includes an electrode plate assembly, a first tab, and a second tab, where the electrode plate assembly includes a first electrode plate and a second electrode plate arranged in a wound manner, the first tab is connected to the first electrode plate and the first housing portion, and the second tab is connected to the second electrode plate and the second housing portion. The electrochemical apparatus further includes a first connector, the first connector including a first arc portion and satisfying: 30° ≤ γ + (10.95 × (R 1 /R 0 ) 3 - 31.0144 × (R 1 /R 0 ) 2 + 28.88 × (R 1 /R 0 ) - 7.012) × β 1 ≤ 180°; and/or, the electrochemical apparatus further includes a second connector, the second connector including a second arc portion and satisfying: 30° ≤ γ - (10.95 × (R 2 /R 0 ) 3 - 31.0144 × (R 2 /R 0 ) 2 + 28.88 × (R 2 /R 0 ) - 7.012) × β 2 ≤ 180°. This application facilitates the reduction of an axial magnetic field at an end face of the electrode plate assembly with a wound structure, thereby facilitating the reduction of interference of the electrochemical apparatus on the electrical device.

Inventors

CHEN, WEN
SU, Shiwei
ZHANG, JUNTAO

Assignees

Ningde Amperex Technology Limited

Dates

Publication Date: 20260506
Application Date: 20230629

Claims (10)

An electrochemical apparatus, characterized in that , comprising: a housing comprising a first housing portion and a second housing portion with opposite polarities; and an electrode assembly accommodated in the housing, wherein the electrode assembly comprises: an electrode plate assembly comprising a first electrode plate and a second electrode plate arranged in a wound manner, wherein the first electrode plate comprises a first current collector and a first active layer located on a surface of the first current collector, the second electrode plate comprises a second current collector and a second active layer located on a surface of the second current collector, and a winding start section of the first active layer is located on a wound inner side of the electrode plate assembly relative to a winding start section of the second active layer; a first tab, wherein the first tab is connected to a first region of a winding tail section of the first current collector and the first housing portion; and a second tab, wherein the second tab is connected to a second region of a winding tail section of the second current collector and the second housing portion, and along a winding direction of the electrode plate assembly from inside to outside, the first region extends beyond the second region; wherein when viewed along a width direction of the first electrode plate, along the winding direction of the electrode plate assembly from inside to outside, an angle formed by rotating a ray from a winding center of the electrode plate assembly to a center of the second region to a ray from the winding center to a center of the first region is denoted as θ; when a winding length of the first region extending beyond the second region is less than one turn, and γ = θ; when the winding length of the first region extending beyond the second region is greater than or equal to one turn, and the number of complete turns of the first region extending beyond the second region is n, and γ = 360° × n + θ; and a distance from the winding center of the electrode plate assembly to the center of the first region is denoted as R 0 ; and the electrochemical apparatus satisfies at least one of the following conditions: (1) the electrochemical apparatus further comprises a first connector located outside the housing, the first connector comprising a first end portion connected to the first housing portion, a second end portion configured to be connected to an external load, and a first arc portion located between the first end portion and the second end portion, wherein the first arc portion comprises a first inner edge close to the winding center of the electrode plate assembly and a first outer edge away from the winding center, a distance from the winding center to the first inner edge is denoted as R 11 , a distance from the winding center to the first outer edge is denoted as R 12 , and an equivalent radius R 1 of the first arc portion is denoted as (R 11 + R 12 )/2; and along an extension direction from the first end portion to the second end portion, the first arc portion comprises a first start end and a first termination end; when an extension direction from the first start end to the first termination end is the same as the winding direction of the electrode plate assembly from inside to outside, along the winding direction of the electrode plate assembly from inside to outside, an angle formed by rotating a ray from the winding center of the electrode plate assembly to the first start end to a ray from the winding center to the first termination end is denoted as α 1 , and β 1 = α 1 ; and when the extension direction from the first start end to the first termination end is opposite to the winding direction of the electrode plate assembly from inside to outside, along a direction opposite to the winding direction of the electrode plate assembly from inside to outside, the angle formed by rotating the ray from the winding center of the electrode plate assembly to the first start end to the ray from the winding center to the first termination end is denoted as α 1 , and β 1 = -α 1 ; satisfying: 30° ≤ γ + (10.95 × (R 1 /R 0 ) 3 - 31.0144 × (R 1 /R 0 ) 2 + 28.88 × (R 1 /R 0 ) - 7.012) × β 1 ≤ 180°; or (2) the electrochemical apparatus further comprises a second connector located outside the housing, the second connector comprising a third end portion connected to the second housing portion, a fourth end portion configured to be connected to an external load, and a second arc portion located between the third end portion and the fourth end portion, wherein the second arc portion comprises a second inner edge close to the winding center of the electrode plate assembly and a second outer edge away from the winding center, a distance from the winding center to the second inner edge is denoted as R 21 , a distance from the winding center to the second outer edge is denoted as R 22 , and an equivalent radius R 2 of the second arc portion is denoted as (R 21 + R 22 )/2; and along an extension direction from the third end portion to the fourth end portion, the second arc portion comprises a second start end and a second termination end; when an extension direction from the second start end to the second termination end is the same as the winding direction of the electrode plate assembly from inside to outside, along the winding direction of the electrode plate assembly from inside to outside, an angle formed by rotating a ray from the winding center of the electrode plate assembly to the second start end to a ray from the winding center to the second termination end is denoted as α 2 , and β 2 = α 2 ; and when the extension direction from the second start end to the second termination end is opposite to the winding direction of the electrode plate assembly from inside to outside, along a direction opposite to the winding direction of the electrode plate assembly from inside to outside, the angle formed by rotating the ray from the winding center of the electrode plate assembly to the second start end to the ray from the winding center to the second termination end is denoted as α 2 , and β 2 = -α 2 ; satisfying: 30° ≤ γ - (10.95 × (R 2 /R 0 ) 3 - 31.0144 × (R 2 /R 0 ) 2 + 28.88 × (R 2 /R 0 ) - 7.012) × β 2 ≤ 180°.
The electrochemical apparatus according to claim 1, characterized in that , the electrochemical apparatus satisfies at least one of the following conditions: 60° ≤ γ + (10.95 × (R 1 /R 0 ) 3 - 31.0144 × (R 1 /R 0 ) 2 + 28.88 × (R 1 /R 0 ) - 7.012) × β 1 ≤ 120°; or 60° ≤ γ - (10.95 × (R 2 /R 0 ) 3 - 31.0144 × (R 2 /R 0 ) 2 + 28.88 × (R 2 /R 0 ) - 7.012) × β 2 ≤ 120°
The electrochemical apparatus according to claim 1, characterized in that , the first tab comprises a first connecting portion and a first bent portion, the first connecting portion is connected to the first region, the first bent portion is bent toward a first end face of the electrode plate assembly, and along the width direction of the first electrode plate, the first bent portion is located on a side of the electrode plate assembly, and the first bent portion is connected to the first housing portion; and the second tab comprises a second connecting portion and a second bent portion, the second connecting portion is connected to the second region, the second bent portion is bent toward a second end face of the electrode plate assembly, the second end face is opposite to the first end face along the width direction of the first electrode plate, and along the width direction of the first electrode plate, the second bent portion is located on a side of the electrode plate assembly facing away from the first bent portion.
The electrochemical apparatus according to claim 3, characterized in that , the electrochemical apparatus satisfies at least one of the following conditions: (1) the first bent portion comprises a third region connected to the first housing portion, an angle between a ray from a center of the third region to the center of the first region and a ray from the center of the third region to the first start end is denoted as η, satisfying η ≤ 45°; (2) the second housing portion comprises a fourth region connected to the second bent portion, and an angle between a ray from a center of the fourth region to the center of the second region and a ray from the center of the fourth region to the second start end is denoted as δ, satisfying δ ≤ 45°; (3) the first housing portion comprises a top wall, a bottom wall, and a side wall, the second housing portion comprises an electrode pole, the top wall is provided with a through hole, and the electrode pole is disposed in the through hole; (4) the first connector is disposed on a side of the first end face; or (5) the second connector is disposed on a side of the second end face.
The electrochemical apparatus according to claim 1, characterized in that , along the winding direction of the electrode plate assembly from inside to outside, the winding tail section of the first current collector comprises a blank section extending beyond the first region and not provided with the first active layer on a surface, and the blank section covers the winding tail section of the second current collector.
The electrochemical apparatus according to claim 1, characterized in that , the electrochemical apparatus satisfies at least one of the following conditions: (1) 30 ° ≤ γ ≤ 450 ° ; (2) 15 ° ≤ α 1 ≤ 210 ° ; (3) 15 ° ≤ α 2 ≤ 210 ° ; or (4) the winding length of the first region extending beyond the second region is less than one turn.
The electrochemical apparatus according to claim 1, characterized in that , the first electrode plate is a negative electrode plate, and the second electrode plate is a positive electrode plate; wherein the winding start section of the first active layer extends beyond the winding start section of the second active layer along the direction opposite to the winding direction of the electrode plate assembly from inside to outside, and/or a winding tail section of the first active layer extends beyond a winding tail section of the second active layer along the winding direction of the electrode plate assembly from inside to outside.
The electrochemical apparatus according to any one of claims 1 to 7, characterized in that , satisfying at least one of the following conditions: (a) the electrode plate assembly further comprises a first separator, wherein the first separator is disposed between the first electrode plate and the second electrode plate, and along the winding direction of the electrode plate assembly from inside to outside, a winding termination end of the first separator extends beyond the first electrode plate; or (b) the electrode plate assembly further comprises a second separator, wherein the second separator is disposed between the first electrode plate and the second electrode plate, and along the winding direction of the electrode plate assembly from inside to outside, a winding termination end of the second separator extends beyond the second electrode plate.
The electrochemical apparatus according to any one of claims 1 to 7, characterized in that , the electrochemical apparatus further comprises an insulating member, and the insulating member is disposed between the housing and the electrode plate assembly.
An electrical device, characterized in that , comprising the electrochemical apparatus according to any one of claims 1 to 9.

Description

TECHNICAL FIELD This application relates to the technical field of energy storage, and in particular, to an electrochemical apparatus and an electrical device. BACKGROUND For a battery with a wound structure, due to its special spiral involute structure, a strong axial magnetic field is generated at an end face of the wound structure, thus causing significant interference on electrical devices such as Bluetooth earphones, and affecting normal use of the electrical devices. Therefore, how to reduce an axial magnetic field of a battery with a wound structure has become an urgent problem to be solved. SUMMARY In view of this, this application provides an electrochemical apparatus to reduce an axial magnetic field of a battery with a wound structure, thereby reducing the interference of the electrochemical apparatus on an electrical device. According to a first aspect of this application, an electrochemical apparatus is provided, where the electrochemical apparatus includes a housing and an electrode assembly; the housing includes a first housing portion and a second housing portion with opposite polarities; the electrode assembly is accommodated in the housing, and the electrode assembly includes an electrode plate assembly, a first tab, and a second tab; the electrode plate assembly includes a first electrode plate and a second electrode plate arranged in a wound manner, where the first electrode plate includes a first current collector and a first active layer located on a surface of the first current collector, and the second electrode plate includes a second current collector and a second active layer located on a surface of the second current collector; a winding start section of the first active layer is located on a wound inner side of the electrode plate assembly relative to a winding start section of the second active layer; the first tab is connected to a first region of a winding tail section of the first current collector and the first housing portion; the second tab is connected to a second region of a winding tail section of the second current collector and the second housing portion; along a winding direction of the electrode plate assembly from inside to outside, the first region extends beyond the second region; when viewed along a width direction of the first electrode plate, along the winding direction of the electrode plate assembly from inside to outside, an angle formed by rotating a ray from a winding center of the electrode plate assembly to a center of the second region to a ray from the winding center to a center of the first region is denoted as θ; when a winding length of the first region extending beyond the second region is less than one turn, and γ = 0; when the winding length of the first region extending beyond the second region is greater than or equal to one turn, and the number of complete turns of the first region extending beyond the second region is n, and γ = 360° × n + θ; and a distance from the winding center of the electrode plate assembly to the center of the first region is denoted as R0; where the electrochemical apparatus satisfies at least one of the following conditions: (1) the electrochemical apparatus further includes a first connector located outside the housing, the first connector including a first end portion connected to the first housing portion, a second end portion configured to be connected to an external load, and a first arc portion located between the first end portion and the second end portion, where the first arc portion includes a first inner edge close to the winding center of the electrode plate assembly and a first outer edge away from the winding center, a distance from the winding center to the first inner edge is denoted as R11, a distance from the winding center to the first outer edge is denoted as R12, and an equivalent radius R1 of the first arc portion is denoted as (R11 + R12)/2; and along an extension direction from the first end portion to the second end portion, the first arc portion includes a first start end and a first termination end; when an extension direction from the first start end to the first termination end is the same as the winding direction of the electrode plate assembly from inside to outside, along the winding direction of the electrode plate assembly from inside to outside, an angle formed by rotating a ray from the winding center of the electrode plate assembly to the first start end to a ray from the winding center to the first termination end is denoted as α1, and β1 = α1; and when the extension direction from the first start end to the first termination end is opposite to the winding direction of the electrode plate assembly from inside to outside, along a direction opposite to the winding direction of the electrode plate assembly from inside to outside, the angle formed by rotating the ray from the winding center of the electrode plate assembly to the first start end to the ray from the winding center to