KR-20260066868-A - Secondary battery

Abstract

The present invention relates to a secondary battery capable of improving electrical insulation characteristics by providing a thicker insulating layer located on the outer side, which is most susceptible to damage from external forces in an electrode assembly, compared to the insulating layer located on the inner side, while simultaneously preventing a decrease in the overall capacity of the electrode assembly due to an increase in the weight and thickness of the insulating layer. For example, the electrode assembly comprises: a first electrode plate having a first electrode blank; a second electrode plate having a second electrode blank; and a separator disposed between the first electrode plate and the second electrode plate, and an insulating layer provided to cover the first electrode blank; and a case for housing the electrode assembly, wherein the thickness of the insulating layer provided on the first electrode plate located on the outermost side of the electrode assembly is thicker than the thickness of the insulating layer provided on the first electrode plate located on the inner side of the electrode assembly.

Inventors

• 정민규
• 이정현
• 박정이
• 박혜민
• 이기욱

Assignees

• 삼성에스디아이 주식회사

Dates

Publication Date

20260512

Application Date

20241105

Claims (20)

1. An electrode assembly comprising: a first electrode plate having a first electrode non-recess; a second electrode plate having a second electrode non-recess; and a separator disposed between the first electrode plate and the second electrode plate, and an insulating layer provided to cover the first electrode non-recess; and It includes a case that accommodates the above electrode assembly, The above electrode assembly is a secondary battery in which the thickness of the insulating layer provided on the first electrode plate located on the outermost side is thicker than the thickness of the insulating layer provided on the first electrode plate located on the inner side of the electrode assembly.
2. In Article 1, The above first electrode plate is A first electrode collector plate that is a metal foil; A first electrode active material provided on at least one surface of the first electrode current collector plate; and A secondary battery comprising a first electrode uncoated portion on one end of the first direction of the first electrode current collector plate, wherein the first electrode active material is not coated.
3. In Article 2, The above insulating layer is a secondary battery in which one end of the first direction covers the sidewall of the first electrode active material.
4. In Paragraph 3, The above insulating layer is a secondary battery having a region that overlaps with the first electrode active material in the first direction.
5. In Article 2, A secondary battery in which the first electrode active material is provided on each side of the first electrode current collector plate, and the insulating layer is provided on each side of the first electrode non-contained portion.
6. In Article 2, A secondary battery in which the thickness of the insulating layer is equal to or thinner than the thickness of the first electrode active material.
7. In Article 2, A secondary battery in which the thickness of the insulating layer is 40% to 70% of the thickness of the first electrode active material.
8. In Article 1, The above electrode assembly The above electrode assembly is a stack type in which a plurality of the first electrode plate, the separator, the second cathode plate, and the separator are sequentially and repeatedly stacked. A secondary battery in which the thickness of the outermost insulating layer provided on the first electrode plate located on the outermost side is thicker than the thickness of the inner insulating layer provided on the first electrode plate located on the inner side.
9. In Article 8, A secondary battery in which the thickness of the inner insulating layer is 50% to 90% of the thickness of the outermost insulating layer.
10. In Article 8, The above insulating layer is a secondary battery in which the thickness of the insulating layer provided on the first electrode plate located at the center of the electrode assembly is thinner than the thickness of the insulating layer provided on the other first electrode plate.
11. In Article 8, The first electrode plate further includes a first electrode tab extending in the first direction from the first electrode non-part, and The above insulating layer is provided to partially cover the surface of the first electrode tab of a secondary battery.
12. In Article 11, The above insulating layer is a secondary battery in which the length in the first direction is shorter than the length in the first direction of the first electrode tab.
13. In Article 11, The above plurality of first electrode tabs are aligned and stacked at the same position in a secondary battery.
14. In Article 1, The above electrode assembly is a jelly-roll type secondary battery in which a laminate in which the first electrode plate, the separator, the second negative electrode plate, and the separator are sequentially stacked is wound.
15. In Article 14, The above insulating layer is a secondary battery in which the thickness gradually increases from the leading edge of the winding to the end of the winding.
16. In Article 14, A secondary battery in which the insulating layer is thicker than the insulating layer provided to cover the outer surface of the first electrode portion compared to the insulating layer provided to cover the inner surface of the first electrode portion.
17. In Article 14, The insulating layer is provided such that the thickness of the insulating layer located in the outermost winding end region of the electrode assembly is thicker than the insulating layer provided in the inner region of the electrode assembly. The above-mentioned winding end region is a secondary battery corresponding to the length in which the first electrode plate located at the outermost side is wound at least once.
18. In Article 17, The thickness of the insulating layer provided in the inner region is uniform for a secondary battery.
19. In Article 1, A secondary battery in which the first electrode plate is a positive electrode plate and the second electrode plate is a negative electrode plate.
20. In Article 1, The above insulating layer is a secondary battery made of ceramic.

Description

Secondary battery The present disclosure relates to a secondary battery. Rechargeable batteries are power storage systems that provide excellent energy density by converting electrical energy into the form of chemical energy for storage. Unlike primary batteries, which are non-rechargeable, rechargeable batteries are widely used in IT devices such as smartphones, cellular phones, laptops, and tablet PCs. Recently, interest in electric vehicles has increased due to the need to prevent environmental pollution, leading to the adoption of high-capacity rechargeable batteries in these vehicles. These rechargeable batteries require characteristics such as high density, high output, and stability. The information described above disclosed in the background technology of this invention is intended only to enhance understanding of the background of the present invention and may therefore include information that does not constitute prior art. The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. FIG. 1 is a perspective view illustrating a secondary battery according to the present invention. Figure 2 is an exploded view of the secondary battery shown in Figure 1. FIG. 3 is an exploded perspective view of a part of the electrode assembly in the secondary battery of FIG. 1 and FIG. 2. Figure 4 is a cross-sectional view taken along the 4-4' line of Figure 3. Figure 5 is an enlarged view of part 5 of Figure 4. Figure 6 is a cross-sectional view of the electrode assembly of Figure 2. FIG. 7 is a perspective view illustrating another example of an electrode assembly in the secondary battery of FIG. 1 and FIG. 2. FIG. 8 is a plan view showing the electrode assembly of FIG. 7 before the first electrode plate is wound. Figure 9 is an example of a cross-sectional view taken along the 9-9' line of Figure 8. Figure 10 is another example of a cross-sectional view taken along the 9-9' line of Figure 8. FIGS. 11a and FIGS. 11b are perspective views illustrating a battery pack including an exemplary secondary battery according to the present invention. FIGS. 12a and FIGS. 12b are a perspective view and a side view illustrating an automobile including an exemplary battery pack according to the present invention. Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings. Instead, based on the principle that the inventor can appropriately define the concepts of terms to best describe their invention, they should be interpreted in a meaning and concept consistent with the technical spirit of the present invention. Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely some of the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention. It should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application. Additionally, as used herein, “comprise, include” and/or “comprising, including” specify the presence of the mentioned features, numbers, steps, actions, parts, elements, and/or groups thereof, and do not exclude the presence or addition of one or more other features, numbers, actions, parts, elements, and/or groups. Additionally, to aid in understanding the invention, the attached drawings are not drawn to actual scale, and the dimensions of some components may be exaggerated. Furthermore, the same reference numerals may be assigned to identical components in different embodiments. The statement that two subjects of comparison are 'identical' means that they are 'substantially identical.' Therefore, substantial identity may include deviations considered low in the industry, for example, deviations within 5%. Additionally, the statement that a parameter is uniform in a given area may mean that it is uniform from an average perspective. Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless specifically stated otherwise, the first component may also be the second component. Throughout the specification, unless specifically stated otherwise, each component may be singular or plural. The fact that any configuration is placed on the "upper (or lower)" of a component or on the "upper (or lower