US-20260128456-A1 - ELECTROCHEMICAL APPARATUS AND ELECTRONIC DEVICE

US20260128456A1US 20260128456 A1US20260128456 A1US 20260128456A1US-20260128456-A1

Abstract

An electrochemical apparatus including an accommodating portion and an electrode assembly accommodated within the accommodating portion. The electrochemical apparatus further includes a metal strip, a sealing member, and a functional layer. The metal strip includes a first portion, a second portion, and a third portion that are connected, where the first portion is within the accommodating portion and connected to the electrode assembly, the accommodating portion is provided with an extension hole, the second portion is disposed in the extension hole, and the third portion extends outside the accommodating portion. The sealing member is disposed between the second portion and an inner wall of the extension hole, and the sealing member is bonded to the accommodating portion. The functional layer is disposed on an outer surface of the second portion and located between the second portion and the sealing member.

Inventors

Haitao Liang

Assignees

NINGDE AMPEREX TECHNOLOGY LIMITED

Dates

Publication Date: 20260507
Application Date: 20251229

Claims (20)

1 . An electrochemical apparatus, comprising an accommodating portion and an electrode assembly accommodated within the accommodating portion, wherein the electrochemical apparatus further comprises: a metal strip, comprising a first portion, a second portion, and a third portion connected sequentially; the first portion being disposed within the accommodating portion and connected to the electrode assembly, the accommodating portion being provided with an extension hole, the second portion being disposed in the extension hole, and the third portion extending outside the accommodating portion; a sealing member, disposed between the second portion and an inner wall surrounding the extension hole, wherein the sealing member is bonded to the accommodating portion; and a functional layer, disposed on an outer surface of the second portion and located between the second portion and the sealing member, wherein the functional layer is configured to melt when a temperature rises to a first threshold.
2 . The electrochemical apparatus according to claim 1 , wherein the electrochemical apparatus further comprises an insulating assembly; and the insulating assembly is disposed on an outer surface of the third portion, the third portion having a conductive region, wherein the insulating assembly does not cover the conductive region.
3 . The electrochemical apparatus according to claim 2 , wherein the metal strip comprises a first surface and a second surface disposed opposite to each other in a first direction; on the first surface, along a second direction, two ends of the third portion respectively have a first region and a second region, and the conductive region is located between the first region and the second region; and the insulating assembly comprises a first insulating layer and a second insulating layer, the first insulating layer being disposed on the first region, and the second insulating layer being disposed on the second region; wherein the first portion, the second portion, and the third portion are sequentially disposed along a third direction; and the first direction, the second direction, and the third direction are perpendicular to each other.
4 . The electrochemical apparatus according to claim 3 , wherein the first insulating layer, the second insulating layer, and the functional layer are integrally formed.
5 . The electrochemical apparatus according to claim 2 , wherein the electrochemical apparatus further comprises a third insulating layer, and the third insulating layer is disposed on the second surface of the third portion.
6 . The electrochemical apparatus according to claim 2 , wherein the third portion further comprises a first side surface and a second side surface disposed opposite to each other in the second direction; and the insulating assembly further comprises a fourth insulating layer, wherein the fourth insulating layer is disposed on the first side surface; and/or the insulating assembly further comprises a fifth insulating layer, wherein the fifth insulating layer is disposed on the second side surface.
7 . The electrochemical apparatus according to claim 1 , wherein a material of the functional layer comprises low-density polyethylene and/or polypropylene, a density of the functional layer is denoted as ρ, and 0.910 g/cm 3 ≤ρ≤0.925 g/cm 3 .
8 . The electrochemical apparatus according to claim 1 , wherein the first threshold is denoted as T 1 , and 110° C.≤T 1 ≤115° C.
9 . The electrochemical apparatus according to claim 1 , wherein a material of the sealing member comprises at least one of polypropylene, o-phenylphenol, polyvinyl chloride, polyethylene terephthalate, polyamide resin, or phenol formaldehyde resin; a melting point of the sealing member is denoted as T 2 , and T 2 ≥120° C.
10 . The electrochemical apparatus according to claim 1 , wherein the sealing member is bonded to the functional layer.
11 . The electrochemical apparatus according to claim 3 , wherein the electrochemical apparatus satisfies at least one of the following conditions: a. along the first direction, a thickness of the first insulating layer is denoted as H 1 , wherein 30 μm≤H 1 ≤40 μm; b. along the first direction, a thickness of the second insulating layer is denoted as H 2 , wherein 30 μm≤H 2 ≤40 μm; c. along the second direction, a width of the first insulating layer is denoted as W 1 , wherein 0.1 mm≤W 1 ≤0.17 mm; or d. along the second direction, a width of the second insulating layer is denoted as W 2 , wherein 0.1 mm≤W 2 ≤0.17 mm.
12 . The electrochemical apparatus according to claim 2 , wherein the electrochemical apparatus comprises at least two metal strips, at least one metal strip being a positive electrode metal strip, and at least one metal strip being a negative electrode metal strip, wherein the positive electrode metal strip and the negative electrode metal strip extend from the same side of the accommodating portion.
13 . The electrochemical apparatus according to claim 2 , wherein the metal strip satisfies at least one of the following conditions: a. along a first direction, a thickness of the metal strip is denoted as H 3 , wherein 0.06 mm≤H 3 ≤0.1 mm; b. along a second direction, a width of the metal strip is denoted as W 3 , wherein 0.2 mm≤W 3 ≤2 mm; and c. along the second direction, a width of the accommodating portion is denoted as W 4 , wherein 1 mm≤W 4 ≤4 mm.
14 . An electronic device, comprising the electrochemical apparatus according to claim 1 .
15 . The electronic device according to claim 14 , wherein the electrochemical apparatus further comprises an insulating assembly; and the insulating assembly is disposed on an outer surface of the third portion, the third portion having a conductive region, wherein the insulating assembly does not cover the conductive region.
16 . The electronic device according to claim 15 , wherein the metal strip comprises a first surface and a second surface disposed opposite to each other in a first direction; on the first surface, along a second direction, two ends of the third portion respectively have a first region and a second region, and the conductive region is located between the first region and the second region; and the insulating assembly comprises a first insulating layer and a second insulating layer, the first insulating layer being disposed on the first region, and the second insulating layer being disposed on the second region; wherein the first portion, the second portion, and the third portion are sequentially disposed along a third direction; and the first direction, the second direction, and the third direction are perpendicular to each other.
17 . The electronic device according to claim 16 , wherein the first insulating layer, the second insulating layer, and the functional layer are integrally formed.
18 . The electronic device according to claim 15 , wherein the electrochemical apparatus further comprises a third insulating layer, and the third insulating layer is disposed on the second surface of the third portion.
19 . The electronic device according to claim 15 , wherein the third portion further comprises a first side surface and a second side surface disposed opposite to each other in the second direction; and the insulating assembly further comprises a fourth insulating layer, wherein the fourth insulating layer is disposed on the first side surface; and/or the insulating assembly further comprises a fifth insulating layer, wherein the fifth insulating layer is disposed on the second side surface.
20 . The electronic device according to claim 14 , wherein a material of the functional layer comprises low-density polyethylene and/or polypropylene, a density of the functional layer is denoted as ρ, and 0.910 g/cm 3 ≤ρ≤0.925 g/cm 3 .

Description

CROSS-REFERENCE TO RELATED APPLICATION The present application is a continuation application of PCT Application S.N. PCT/CN2023/103809, filed on Jun. 29, 2023, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD Embodiments of this application relate to the field of electrochemical technologies, and in particular, to an electrochemical apparatus and an electronic device. BACKGROUND With the increasing demand for electronic products, lithium-ion batteries are correspondingly required to be suitable for various spatial configurations of different electronic products. For example, ultra-narrow lithium-ion batteries are needed for elongated products such as smart glasses and earphones. In the prior art, batteries with a width or diameter not exceeding 6 millimeters are generally referred to as ultra-narrow lithium-ion batteries. Due to the small size, ultra-narrow batteries are difficult provided with pressure relief structures. During use, ultra-narrow batteries may experience thermal runaway, leading to increased internal pressure within an accommodating portion, causing the accommodating portion to swell and even causing safety risks such as battery explosion. SUMMARY Embodiments of this application are intended to provide a battery cell and an electrochemical apparatus to reduce swelling and lower the risk of battery explosion. The following technical solution is used in some embodiments of this application to solve the technical problem: According to a first aspect, this application provides an electrochemical apparatus including an accommodating portion and an electrode assembly accommodated within the accommodating portion. The electrochemical apparatus further includes a metal strip, a sealing member, and a functional layer. The metal strip includes a first portion, a second portion, and a third portion that are connected, where the first portion is within the accommodating portion and connected to the electrode assembly, the accommodating portion is provided with an extension hole, the second portion is disposed in the extension hole, and the third portion extends outside the accommodating portion. The sealing member is disposed between the second portion and an inner wall of the extension hole, and the sealing member is bonded to the accommodating portion. The functional layer is disposed on an outer surface of the second portion and located between the second portion and the sealing member, where the functional layer is configured to melt when a temperature rises to a first threshold. In the above technical solution, the functional layer is provided between the second portion and the sealing member, when the electrochemical apparatus is in a short-circuit thermal runaway or thermal shock test, the temperature rises to the first threshold, and the functional layer melts to form an exhaust passage communicating the interior and exterior of the accommodating portion, thereby rapidly discharging gas and heat from within the accommodating portion to alleviate swelling of the electrochemical apparatus and effectively lower the risk of explosion of the electrochemical apparatus. In some preferred embodiments, the electrochemical apparatus further includes an insulating assembly. The insulating assembly is disposed on an outer surface of the third portion, the third portion having a conductive region, where the insulating assembly does not cover the conductive region. The insulating assembly is provided on the third portion outside the accommodating portion, the strength and toughness of the metal strip may be improved, thereby reducing bending of the metal strip. Additionally, the insulating assembly can separate positive and negative electrode metal strips of the electrochemical apparatus to lower the risk of short-circuit due to direct contact between the positive and negative electrode metal strips. In addition, when preparing multiple electrochemical apparatuses, the insulating assembly also isolates metal strips of other electrochemical apparatuses to further lower the risk of short-circuit of the electrochemical apparatus. In some preferred embodiments, the metal strip includes a first surface and a second surface disposed opposite to each other in a first direction. On the first surface, along a second direction, two ends of the third portion respectively have a first region and a second region, and the conductive region is located between the first region and the second region. The insulating assembly includes a first insulating layer and a second insulating layer, where the first insulating layer is disposed on the first region, and the second insulating layer is disposed on the second region. The first portion, the second portion, and the third portion are sequentially disposed along a third direction, where the first direction, the second direction, and the third direction are perpendicular to each other. The insulating layers are disposed only on the first r