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EP-4738595-A1 - ELECTROCHEMICAL APPARATUS AND ELECTRIC DEVICE

EP4738595A1EP 4738595 A1EP4738595 A1EP 4738595A1EP-4738595-A1

Abstract

This application discloses an electrochemical apparatus and an electric device. The electrochemical apparatus includes a first housing portion and a second housing portion of opposite polarities, an electrode assembly, and a first connector. The electrode assembly includes an electrode plate assembly, a first tab, and a second tab. A first electrode plate of the electrode plate assembly is located on a winding inner side relative to a second electrode plate. The first tab is connected to a first region of the first electrode plate. The first tab includes a second region connected to the first housing portion. The second tab is connected to a third region of the second electrode plate. The first connector is connected to the first housing portion, and includes a fourth region configured to be connected to an electric device. A winding length of the first region extending beyond the third region is less than one turn. An angle formed by rotating the third region to the first region around a winding center is θ, satisfying: 45° ≤ θ ≤ 135°. An angle formed by rotating the first region to the fourth region around the second region is α, satisfying: -60° ≤ α ≤ 45°. The electrochemical apparatus of this application is conducive to reducing an axial magnetic field at the end face, thereby reducing interference with the electric device.

Inventors

  • CHEN, WEN
  • SU, Shiwei
  • ZHANG, JUNTAO

Assignees

  • Ningde Amperex Technology Limited

Dates

Publication Date
20260506
Application Date
20230629

Claims (10)

  1. An electrochemical apparatus, characterized in that , the electrochemical apparatus comprises a housing, an electrode assembly, and a first connector, the electrode assembly is accommodated in the housing, and the first connector is located outside the housing; the housing comprises a first housing portion and a second housing portion of opposite polarities; the electrode assembly comprises an electrode plate assembly, a first tab, and a second tab; the electrode plate assembly comprises a first electrode plate and a second electrode plate arranged in a wound manner, 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 winding inner side of the electrode plate assembly relative to a winding start section of the second active layer; the first tab comprises a first connecting portion and a first bent portion, the first connecting portion is connected to a first region of a winding tail section of the first current collector, the first bent portion is bent toward a first end face of the electrode plate assembly, and along a width direction of the first electrode plate, the first bent portion is located on one side of the electrode plate assembly, and the first bent portion comprises a second region connected to the first housing portion; the second tab comprises a second connecting portion and a second bent portion, the second connecting portion is connected to a third region of a winding tail section of the second current collector, the second bent portion is bent toward a second end face of the electrode plate assembly, the second end face is disposed 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 one side of the electrode plate assembly facing away from the first bent portion; along a winding direction of the electrode plate assembly from inside to outside, the first region extends beyond the third region, and a winding length of the first region extending beyond the third region is less than one turn; the first connector is connected to the first housing portion, and comprises a fourth region configured to be connected to an external load; when viewed along the 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 third region to a ray from the winding center to a center of the first region is θ, satisfying: 45° ≤ θ ≤ 135°; when viewed along the width direction of the first electrode plate, an angle formed by rotating a ray from a center of the second region to the center of the first region to a ray from the center of the second region to a center of the fourth region is α, satisfying: -60° ≤ α ≤ 45°; and along the winding direction of the electrode plate assembly from inside to outside, the angle α formed by rotating the ray from the center of the second region to the center of the first region to the ray from the center of the second region to the center of the fourth region is a positive value; and along a direction opposite to the winding direction of the electrode plate assembly from inside to outside, the angle α formed by rotating the ray from the center of the second region to the center of the first region to the ray from the center of the second region to the center of the fourth region is a negative value.
  2. The electrochemical apparatus according to claim 1, characterized in that , the electrochemical apparatus satisfies at least one of the following conditions: (1) 60 ° ≤ θ ≤ 120 ° ; or (2) − 25 ° ≤ α ≤ 25 ° .
  3. The electrochemical apparatus according to claim 1, characterized in that , 30° ≤ θ + α ≤ 135°.
  4. 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, satisfying at least one of the following conditions: (1) along the direction opposite to the winding direction of the electrode plate assembly from inside to outside, the winding start section of the first active layer extends beyond the winding start section of the second active layer; or (2) along the winding direction of the electrode plate assembly from inside to outside, a winding tail section of the first active layer extends beyond a winding tail section of the second active layer.
  5. The electrochemical apparatus according to claim 1, characterized in that , the first housing portion comprises a top wall, a bottom wall, and a sidewall; the first bent portion is connected to the bottom 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.
  6. The electrochemical apparatus according to claim 5, 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 uncoated with the first active layer on any surface, and the blank section covers the winding tail section of the second current collector.
  7. The electrochemical apparatus according to claim 1, characterized in that , the second bent portion comprises a fifth region connected to the second housing portion, the electrochemical apparatus further comprises a second connector, and the second connector is connected to the second housing portion and comprises a sixth region configured to be connected to an external load; when viewed along the width direction of the first electrode plate, an angle formed by rotating a ray from a center of the fifth region to the center of the third region to a ray from the center of the fifth region to a center of the sixth region is β, satisfying: -60° ≤ β ≤ 45°; and along the winding direction of the electrode plate assembly from inside to outside, the angle β formed by rotating the ray from the center of the fifth region to the center of the third region to the ray from the center of the fifth region to the center of the sixth region is a positive value; and along the direction opposite to the winding direction of the electrode plate assembly from inside to outside, the angle β formed by rotating the ray from the center of the fifth region to the center of the third region to the ray from the center of the fifth region to the center of the sixth region is a negative value.
  8. The electrochemical apparatus according to any one of claims 1 to 7, characterized in that , the electrochemical apparatus satisfies at least one of the following conditions: (1) the electrode plate assembly further comprises a first separator, 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 tail section of the first separator extends beyond the first electrode plate; or (2) the electrode plate assembly further comprises a second separator, 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 tail section of the second separator extends beyond the second electrode plate.
  9. The electrochemical apparatus according to any one of claims 1 to 7, characterized in that , the electrochemical apparatus further comprises an insulation piece, and the insulation piece is disposed between the housing and the electrode plate assembly.
  10. An electric device, characterized in that , the electric device comprises 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 electric device. BACKGROUND For a battery with a wound structure, due to its special spiral involute structure, a relatively strong axial magnetic field is generated at an end face of the wound structure. This causes significant interference with electric devices such as Bluetooth earphones, and affects normal use of the electric devices. SUMMARY In view of the above situation, this application provides an electrochemical apparatus that is conducive to reducing an axial magnetic field at an end face of a wound structure, and consequently reducing the interference from the electrochemical apparatus to an electric device. According to a first aspect, this application provides an electrochemical apparatus. The electrochemical apparatus includes a housing, an electrode assembly, and a first connector. The electrode assembly is accommodated in the housing. The first connector is located outside the housing. The housing includes a first housing portion and a second housing portion of opposite polarities. 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. The first electrode plate includes a first current collector and a first active layer located on a surface of the first current collector. 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 winding inner side of the electrode plate assembly relative to a winding start section of the second active layer. The first tab includes a first connecting portion and a first bent portion. The first connecting portion is connected to a first region of a winding tail section of the first current collector. The first bent portion is bent toward a first end face of the electrode plate assembly. Along a width direction of the first electrode plate, the first bent portion is located on one side of the electrode plate assembly. The first bent portion includes a second region connected to the first housing portion. The second tab includes a second connecting portion and a second bent portion. The second connecting portion is connected to a third region of a winding tail section of the second current collector. The second bent portion is bent toward a second end face of the electrode plate assembly. The second end face is disposed opposite to the first end face along the width direction of the first electrode plate. Along the width direction of the first electrode plate, the second bent portion is located on one side of the electrode plate assembly facing away from the first bent portion. Along a winding direction of the electrode plate assembly from inside to outside, the first region extends beyond the third region, and a winding length of the first region extending beyond the third region is less than one turn. The first connector is connected to the first housing portion, and includes a fourth region configured to be connected to an external load. When viewed along the 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 third region to a ray from the winding center to a center of the first region is θ, satisfying: 45° ≤ θ ≤ 135°. When viewed along the width direction of the first electrode plate, an angle formed by rotating a ray from a center of the second region to the center of the first region to a ray from the center of the second region to a center of the fourth region is α, satisfying: -60° ≤ α ≤ 45°. Along the winding direction of the electrode plate assembly from inside to outside, the angle α formed by rotating the ray from the center of the second region to the center of the first region to the ray from the center of the second region to the center of the fourth region is a positive value. Along a direction opposite to the winding direction of the electrode plate assembly from inside to outside, the angle α formed by rotating the ray from the center of the second region to the center of the first region to the ray from the center of the second region to the center of the fourth region is a negative value. Through research, the inventors of this application finds that due to the special spiral involute structure of a battery of a wound structure, an effective current path length of the first electrode plate on the winding inner side is less than that of the second electrode plate on the winding outer side, resulting in a relatively strong axial magnetic field at both end faces of the jelly roll. In addition, the current flowing through t