JP-7856329-B2 - Electrode tab protective tape and secondary battery containing the same

JP7856329B2JP 7856329 B2JP7856329 B2JP 7856329B2JP-7856329-B2

Inventors

ジ・スン・イ
ミ・エ・アン
ジュン・シク・オ

Assignees

エルジーエナジーソリューションリミテッド

Dates

Publication Date: 20260511
Application Date: 20220513
Priority Date: 20210624

Claims (6)

An electrode tab protective tape comprising an adhesive layer containing an adhesive and a conductive material, and an insulating layer provided on one surface of the adhesive layer, The electrode tab protective tape has the other side of the adhesive layer attached to the bent portion of the electrode tab. An electrode tab protective tape characterized in that the insulating layer has a larger surface area than the adhesive layer.
The insulating layer is The electrode tab protection tape according to claim 1, characterized in that it overlaps so as to protrude along the periphery in the width direction of the adhesive layer.
The insulating layer is The electrode tab protection tape according to claim 1, characterized in that it overlaps so as to protrude along the periphery of the adhesive layer in the width direction and longitudinal direction.
An electrode assembly in which electrodes and a separation membrane are stacked; Includes an electrode tab drawn out from the electrode; and an electrode tab protective tape attached to the electrode tab, The electrode tab protective tape is An adhesive layer comprising an adhesive and a conductive material; and an insulating layer provided on one surface of the adhesive layer, The electrode tab protective tape has the other side of the adhesive layer attached to the electrode tab. The insulating layer is formed with a larger area than the adhesive layer. The electrode tab is The electrode tab is bent in a V-shape along its longitudinal direction, and includes a bent portion where an inner and outer bent portion are formed. The electrode tab protective tape is A secondary battery characterized in that the exposed surface of the adhesive layer is attached so as to surround the outer surface of the bend in the bent portion .
The electrode tab protective tape is The secondary battery according to claim 4 , characterized in that it is attached so as to surround both one surface of the electrode assembly and the outer surface of the bend of the bent portion.
The electrode tab protective tape is The secondary battery according to claim 4, characterized in that the exposed surface of the adhesive layer is attached so as to surround the inside of the bend of the bent portion.

Description

[Cross-reference of related applications] This application claims priority based on Korean Patent Application No. 10-2021-0082711 dated June 24, 2021, and all content disclosed in the said Korean Patent Application is incorporated herein by reference. The present invention relates to an electrode tab protective tape and a secondary battery containing the same. The electrode tab protective tape is attached to an electrode tab made of a thin film material, preventing disconnection failures due to cracks in the electrode tab, and ensuring continuous current flow, thereby preventing malfunctions in the secondary battery. The invention also relates to a secondary battery containing the same. Unlike primary batteries, which cannot be recharged, secondary batteries are batteries that can be charged and discharged. Types of secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, and lithium-ion polymer batteries. These secondary batteries are used not only in small products such as digital cameras, laptops, mobile phones, PDAs, and e-bikes, but also in large products requiring high output, such as electric vehicles and hybrid vehicles, as well as in power storage devices and backup power storage devices that store surplus generated electricity and renewable energy. Such rechargeable batteries are classified into pouch type and can type, depending on the material of the battery case that houses the electrode assembly. Pouch type batteries house the electrode assembly in a pouch made of a flexible polymer material with an irregular shape. Can type batteries house the electrode assembly in a case made of a material with a consistent shape, such as metal or plastic. Figure 1(a) shows a side view of a conventional secondary battery, although the battery case is omitted. Referring to Figure 1, a typical secondary battery structure includes an electrode assembly 20 having an alternating layering of electrodes (negative electrode, positive electrode) and a separator membrane, and a plurality of electrode tabs (negative electrode tab, positive electrode tab) 30 extending from the electrode assembly 20. Each of the electrode tabs 30 is connected to an electrode lead (negative electrode lead, positive electrode lead). In other words, the electrode assembly 20 is a power generation element in which positive and negative electrode plates are sequentially stacked with a separation membrane in between. Multiple positive electrode tabs extend from multiple positive electrode plates, and multiple negative electrode tabs extend from multiple negative electrode plates. Such an electrode assembly 20 is housed in a battery case (not shown), which is a pouch-type outer material, and an electrolyte is injected into it. On the other hand, multiple electrode tabs 30 are welded together to the electrode lead using an ultrasonic welding device. Subsequently, the electrode tabs 30 welded to the electrode lead are bent into a roughly V-shape. This bent portion A of the electrode tab is sometimes referred to as the V-forming portion. However, due to the thinning of the electrode tab 30, cracks or fractures of the electrode tab 30 frequently occur at the bent portion A, as shown in Figure 1(b). Figure 1(b) is a bottom view of the bent portion A in Figure 1(a), showing the state in which a crack has occurred at the bent portion A of the electrode tab 30. Thus, when cracks occur in the electrode tab 30, the current cannot flow smoothly, resulting in problems such as wire breakage and deterioration of the secondary battery's quality. Therefore, there is a need to develop a product that solves the aforementioned problems. This is a side view of a conventional secondary battery and a bottom view showing a crack in the electrode tab of the secondary battery.This is a cross-sectional view showing an electrode tab protective tape according to Embodiment 1 of the present invention.This is a plan view showing the electrode tab protection tape according to Embodiment 1 of the present invention.This is a perspective view showing a secondary battery according to Example 2 of the present invention.This figure shows how electrode tab protective tape is attached to a secondary battery according to Embodiment 2 of the present invention. The following describes preferred embodiments of the present invention in detail, with reference to the attached figures, so that those with ordinary skill in the art to which the invention pertains can easily implement it. However, the present invention may be embodied in many different forms and is not limited to or restricted by the following embodiments. To clearly explain the present invention, detailed descriptions of parts unrelated to the description or of related prior art that could unnecessarily obscure the gist of the invention are omitted. In assigning reference numerals to the components of each figure in this specification, the same or similar reference numerals