CN-122029693-A - Battery cell, battery device and electricity utilization device

CN122029693ACN 122029693 ACN122029693 ACN 122029693ACN-122029693-A

Abstract

A battery unit (100), a battery device (1100) and an electric device are provided, the battery unit (100) comprises a shell (200) and an electrode assembly (101), the shell (200) is provided with an electrode leading-out part (2011), at least part of the electrode assembly (101) is arranged in the shell (200), the electrode assembly (101) comprises a first pole piece (1), the first pole piece (1) comprises a current collector (10), a conductive member (30) and an active substance layer (20), the conductive member (30) is electrically connected with the electrode leading-out part (2011), the current collector (10) comprises an insulating base (11) and a metal layer (12), the insulating base (11), the metal layer (12) and the active substance layer (20) are stacked along the thickness direction of the current collector (10), at least part of the metal layer (12) is positioned between the insulating base (11) and the active substance layer (20), the metal layer (12) comprises a first metal part (121) and a second metal part (122) which are arranged along a first direction and connected with the first direction, the first direction is perpendicular to the thickness direction of the current collector (10), and at least part of the first metal part (121) is covered with the active substance layer (20), the electrode assembly (101) comprises a first insulating member (41), at least part of the second metal part (122) is not covered with the active material layer (20), the conductive member (30) is welded on the surface of the second metal part (122) facing away from the insulating base body (11) and forms a first welding mark (51), and the first insulating member (41) covers at least part of the first welding mark (51).

Inventors

YANG JIAN
WANG YAOHUI
Deng Bokai
HUANG SIYING
XUE QINGRUI

Assignees

宁德时代新能源科技股份有限公司

Dates

Publication Date: 20260512
Application Date: 20240830
Priority Date: 20240723

Claims (20)

A battery cell, comprising: a housing provided with an electrode lead-out portion; The electrode assembly is at least partially arranged in the shell, and comprises a first pole piece, wherein the first pole piece comprises a current collector, a conductive member and an active material layer, and the conductive member is electrically connected with the electrode lead-out part; The current collector comprises an insulating substrate and a metal layer, wherein the insulating substrate, the metal layer and the active material layer are stacked along the thickness direction of the current collector, and at least part of the metal layer is positioned between the insulating substrate and the active material layer; The metal layer comprises a first metal part and a second metal part which are arranged along a first direction and connected, wherein the first direction is perpendicular to the thickness direction of the current collector, at least part of the first metal part is covered with the active material layer, and at least part of the second metal part is not covered with the active material layer; The electrode assembly includes a first insulating member covering at least a portion of the first solder.
The battery cell of claim 1, wherein the first insulator protrudes from an edge of the first solder away from the active material layer in a direction in which the first metal portion is directed toward the second metal portion, and/or wherein the first insulator protrudes from an edge of the first solder near the active material layer in a direction in which the second metal portion is directed toward the first metal portion.
The battery cell according to claim 1 or2, wherein the conductive member includes a first connection portion and at least one second connection portion, the first connection portion and the second connection portion are connected, the second connection portion is electrically connected to the electrode lead-out portion, and the first connection portion is welded to a surface of the second metal portion facing away from the insulating base and forms the first solder.
The battery cell of claim 3, wherein the second metal portion comprises at least one protrusion; The sum of the dimensions of all the protruding portions is smaller than the dimension of the first metal portion in a second direction perpendicular to the first direction and the thickness direction of the current collector; The first connecting portion comprises at least one first connecting sub-portion, the first connecting sub-portion is connected with the second connecting portion, the first connecting sub-portion covers the surface of the protruding portion, which faces away from the insulating substrate, and the first connecting sub-portion corresponds to the protruding portion one by one.
The battery cell of claim 4, wherein the first insulating member comprises at least one first insulating portion, wherein the first insulating portion covers a surface of the first connecting sub-portion facing away from the protruding portion, and wherein the first connecting sub-portions are in one-to-one correspondence with the first connecting sub-portions.
The battery cell of claim 5, wherein the first solder comprises at least one first solder portion, the first connector portion being soldered to a surface of the protrusion facing away from the insulating substrate and forming the first solder portion; The first insulating portion covers at least part of the first soldering portion.
The battery cell of claim 6, wherein the tab comprises a first tab portion and a second tab portion, the first tab portion being connected between the second tab portion and the first metal portion; the first protrusion has a larger dimension than the second protrusion along the second direction; The first welding part comprises a first welding sub-part, the first connecting part is welded to the first protruding sub-part and forms the first welding sub-part, and the first insulating part covers at least part of the first welding sub-part; And/or the first welding part comprises a second welding part, the first connecting part is welded on the second protruding part and forms the second welding part, and the first insulating part covers at least part of the second welding part.
The battery cell according to claim 6 or 7, wherein the first insulating portion protrudes from an edge of the first solder portion away from the active material layer in a direction in which the first metal portion is directed toward the second metal portion, and/or the first insulating portion protrudes from an edge of the first solder portion near the active material layer in a direction in which the second metal portion is directed toward the first metal portion.
The battery cell according to any one of claims 6 to 8, wherein along the second direction, opposite side surfaces of the protruding portion are respectively flush with opposite side surfaces of the corresponding first connection sub-portion, and opposite edges of the first solder portion are respectively flush with opposite side surfaces of the corresponding first connection sub-portion.
The battery cell according to any one of claims 5 to 9, wherein at least one of opposite side portions of the first insulating portion protrudes from a side surface of the same side as the corresponding first connection sub-portion in the second direction.
The battery cell according to any one of claims 5 to 10, wherein the first insulating portion protrudes from a side of the corresponding first connection sub-portion away from the active material layer in a direction in which the first metal portion is directed toward the second metal portion, and/or the first insulating portion protrudes from a side of the corresponding first connection sub-portion close to the active material layer in a direction in which the second metal portion is directed toward the first metal portion.
The battery cell according to any one of claims 5 to 11, wherein the number of the protruding portions is plural, the first connecting portions include plural first connecting sub-portions, the plural protruding portions are disposed at intervals along the second direction, the plural first connecting sub-portions are disposed at intervals along the second direction, the number of the second connecting portions is plural, the plural second connecting portions are disposed at intervals along the second direction, and the first connecting sub-portions are connected to the second connecting portions in a one-to-one correspondence.
The battery cell of claim 12, wherein adjacent ones of the first insulating portions are disposed apart or contiguous.
The battery cell of any one of claims 2-13, wherein the second metal portion comprises a transition portion and at least one protruding portion, the transition portion being connected between the protruding portion and the first metal portion; the size of the transition part is larger than the sum of the sizes of all the protruding parts along a second direction, wherein the second direction is perpendicular to the first direction and the thickness direction of the current collector.
The battery cell of claim 14, wherein the first metal portion has a dimension L 1 and the transition portion has a dimension L 2 ,0.8≤L 2 /L 1 ≤1 in the second direction.
The battery cell of claim 14 or 15, wherein the first weld includes a second weld, the first connection includes a second connector portion connected to the second connection, and the second connector portion is welded to the transition and forms the second weld.
The battery cell of claim 16, wherein the transition portion has a dimension L 2 and the second weld portion has a dimension L 3 ,0.8≤L 3 /L 2 ≤1 in the second direction.
The battery cell of claim 16 or 17, wherein a side of the transition portion facing away from the first metal portion, an edge of the second solder portion facing away from the active material layer, and a side of the second connector portion facing away from the active material layer are flush.
The battery cell of any one of claims 16-18, wherein the first insulating member comprises a second insulating portion that covers at least a portion of the second solder portion.
The battery cell of claim 19, wherein the second insulating portion protrudes from an edge of the second solder portion away from the active material layer in a direction in which the first metal portion is directed, and/or wherein the second insulating portion protrudes from an edge of the second solder portion closer to the active material layer in a direction in which the second metal portion is directed.

Description

Battery cell, battery device and electricity utilization device The present application claims priority from international patent application PCT/CN2024/106988 entitled "battery cell, battery device and electric device" filed on month 07 of 2024, the entire contents of which are incorporated herein by reference. Technical Field The application belongs to the technical field of batteries, and particularly relates to a battery cell, a battery device and an electricity utilization device. Background Battery cells are widely used in electronic devices such as cellular phones, notebook computers, battery cars, electric vehicles, electric airplanes, electric ships, electric toy vehicles, electric toy ships, electric toy airplanes, electric tools, and the like. The battery device comprises one or more battery cells to meet the use requirements of different electric capacities, but in the technology of the battery cells, how to improve the use reliability of the battery cells is an important research direction. The statements made above merely serve to provide background information related to the present disclosure and may not necessarily constitute prior art. Content of the application The embodiment of the application aims to provide a battery cell, a battery device and an electric device, which can improve the use reliability of the battery cell. The technical scheme adopted by the embodiment of the application is as follows: In a first aspect, in some embodiments, a battery cell is provided, the battery cell includes a case and an electrode assembly, the case is provided with an electrode lead-out portion, at least part of the electrode assembly is arranged in the case, the electrode assembly includes a first electrode sheet, the first electrode sheet includes a current collector, a conductive member and an active material layer, the conductive member is electrically connected with the electrode lead-out portion, the current collector includes an insulating base and a metal layer, the insulating base, the metal layer and the active material layer are stacked along a thickness direction of the current collector, at least part of the metal layer is located between the insulating base and the active material layer, the metal layer includes a first metal portion and a second metal portion which are arranged and connected along a first direction, the first direction is perpendicular to the thickness direction of the current collector, at least part of the first metal portion is covered with the active material layer, at least part of the second metal portion is uncovered with the active material layer, the conductive member is welded on a surface of the second metal portion facing away from the insulating base, and forms a first weld, and the electrode assembly includes a first insulator, the first insulator is covered on at least part of the first weld. By adopting the technical scheme of the embodiment, the first insulating piece covers at least part of the first welding mark, the first insulating piece can block burrs of the first welding mark, the short circuit risk of the battery monomer is reduced, the use reliability of the battery monomer is improved, the current collector adopts a composite structure of an insulating matrix and a metal layer, the thickness of the metal layer is small compared with that of a pure metal current collector, burrs generated in the manufacturing process of the current collector are small, the internal short circuit risk of the battery monomer is reduced, and the use reliability of the battery monomer is improved. In some embodiments, the first insulator protrudes beyond the edge of the first solder away from the active material layer in a direction in which the first metal portion points toward the second metal portion, and/or the first insulator protrudes beyond the edge of the first solder closer to the active material layer in a direction in which the second metal portion points toward the first metal portion. By adopting the technical scheme of the embodiment, the first insulating piece can block burrs at the edges of the relative distribution of the first welding marks along the first direction, so that the short circuit risk of the battery cell is reduced, and the use reliability of the battery cell is improved. In some embodiments, the conductive member includes a first connection portion and at least one second connection portion, the first connection portion and the second connection portion being connected, the second connection portion being electrically connected to the electrode lead-out portion, the first connection portion being soldered to a surface of the second metal portion facing away from the insulating substrate and forming a first solder mark. By adopting the technical scheme of the embodiment, the second connecting part is arranged, so that the second connecting part can be conveniently connected with the electrode leading-out part, and the battery cell i