CN-115280566-B - Secondary battery

CN115280566BCN 115280566 BCN115280566 BCN 115280566BCN-115280566-B

Abstract

The present invention relates to a secondary battery supporting a central portion of an electrode assembly to enhance stability and reliability. For example, a secondary battery is disclosed, the secondary battery including an electrode assembly formed by winding a first electrode plate, a separator, and a second electrode plate, a case for accommodating the electrode assembly, a current collecting plate electrically connected to the first electrode plate and coupled to an upper portion of the electrode assembly, and a core insulating member coupled to a winding center of the electrode assembly at the upper portion of the current collecting plate, wherein the core insulating member includes an insertion portion having an inner hole and a flange portion extending in a horizontal direction from an upper end of the insertion portion.

Inventors

LI YUANYI
Pu Jiankui
ZHANG RENRONG
Pu Zhengxuan
Shen Zuoyan
Yan Zhouzhi
Ding Xianji
JIN WENCHENG
Shen Ruien

Assignees

三星SDI株式会社

Dates

Publication Date: 20260512
Application Date: 20210623
Priority Date: 20200810

Claims (9)

1. A secondary battery, the secondary battery comprising: an electrode assembly formed by winding a first electrode plate, a separator, and a second electrode plate; A case for accommodating the electrode assembly; a current collecting plate electrically connected to the first electrode plate and coupled to an upper portion of the electrode assembly, and A core insulating member coupled to a winding center of the electrode assembly at an upper portion of the current collecting plate, Wherein the core insulation member includes an insertion portion having an inner hole and a flange portion extending in a horizontal direction from an upper end of the insertion portion, Wherein the current collecting plate is formed of a circular plate to correspond to a cross section of the electrode assembly, and includes a center hole formed at the center, and Wherein the insertion part is inserted into the electrode assembly through the central hole, Wherein the first electrode plate includes a first electrode uncoated portion, Wherein the first electrode uncoated portion protrudes beyond the separator, Wherein the first electrode uncoated portion protrudes to an upper portion of the electrode assembly to be electrically connected to the current collecting plate.
2. The secondary battery according to claim 1, wherein a length of the insertion portion is greater than a length of the first electrode plate protruding from an upper end of the separator.
3. The secondary battery according to claim 1, wherein the insertion portion is formed vertically from the flange portion.
4. The secondary battery according to claim 1, wherein an upper diameter and a lower diameter of the inner hole are equal to each other, and a thickness of an upper end of the insertion portion is greater than a thickness of a lower end.
5. The secondary battery according to claim 1, wherein an upper diameter of the inner hole is larger than a lower diameter, and thicknesses of an upper end and a lower end of the insertion portion are equal to each other.
6. The secondary battery according to claim 1, wherein the core insulating member further comprises a fixing groove between the flange portion and the insertion portion, the current collecting plate being fixed to the fixing groove.
7. The secondary battery according to claim 1, wherein the insertion portion includes a cut-out portion that extends from a top to a bottom and divides the insertion portion into a plurality of regions.
8. The secondary battery according to claim 7, wherein the cutout portion is opened when an electrolyte is injected into the case.
9. The secondary battery according to claim 1, wherein the core insulating member further comprises an extension portion extending in a horizontal direction from one side of the flange portion to cover a portion of the current collecting plate.

Description

Secondary battery Technical Field The present invention relates to a secondary battery. Background Unlike a conventional primary battery, which cannot be recharged, a secondary battery can be recharged. A low-capacity secondary battery composed of a single battery cell may be used as a power source for various portable small-sized electronic devices such as smart phones, function phones, notebook computers, digital cameras, and video cameras. A high-capacity secondary battery in which tens of battery cells are connected in a battery pack may be used as a power source for a motor driver, such as a motor driver in a hybrid vehicle or an electric vehicle. Such lithium ion secondary batteries may be classified into cylindrical secondary batteries, prismatic secondary batteries, and pouch-shaped secondary batteries according to their configurations. In particular, a cylindrical secondary battery generally includes a cylindrical electrode assembly, a cylindrical case to which the electrode assembly is coupled, an electrolyte injected into the case to enable lithium ions to move, and a cap assembly coupled to one side of the case to prevent leakage of the electrolyte and to prevent separation of the electrode assembly. The above information disclosed in this background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art. Disclosure of Invention Technical problem The present invention provides a secondary battery supporting a central portion of an electrode assembly to enhance stability and reliability. Technical proposal The secondary battery according to the present invention may include an electrode assembly formed by winding a first electrode plate, a separator, and a second electrode plate, a case for accommodating the electrode assembly, a current collecting plate electrically connected to the first electrode plate and coupled to an upper portion of the electrode assembly, and a core insulating member coupled to a winding center of the electrode assembly at the upper portion of the current collecting plate, wherein the core insulating member includes an insertion portion having an inner hole and a flange portion extending in a horizontal direction from an upper end of the insertion portion. The current collecting plate may include a central hole formed at the center, and the insertion part may be inserted into the electrode assembly through the central hole. The length of the insertion portion may be greater than the length of the first electrode plate protruding from the upper end of the separator. The insertion portion may be vertically formed from the flange portion. The upper and lower diameters of the inner bore may be equal to each other, and the thickness of the upper end of the insertion portion may be greater than the thickness of the lower end. The upper diameter of the inner bore may be greater than the lower diameter, and the thicknesses of the upper and lower ends of the insertion portion may be equal to each other. The core insulation member may be located between the flange portion and the insertion portion, and may further include a fixing groove to which the current collecting plate is fixed. The insert may include a cut-out portion extending from the top to the bottom and dividing the insert into a plurality of regions. The cut-out portion may be opened when the electrolyte is injected into the case. The core insulating member may further include an extension portion extending in a horizontal direction from one side of the flange portion to cover a portion of the current collecting plate. Advantageous effects In the secondary battery according to the embodiment of the present invention, by including the core insulating member coupled to the winding center of the electrode assembly, the center portion of the electrode assembly may be prevented from collapsing after electrolyte injection, thereby enhancing stability and reliability of the secondary battery. Drawings Fig. 1 is a sectional view illustrating a secondary battery according to an embodiment of the present invention. Fig. 2 is an exploded perspective view showing a part of the secondary battery. Fig. 3a is a perspective view showing a core insulation member according to an embodiment of the present invention, and fig. 3b is a sectional view thereof. Fig. 4a is a perspective view showing a core insulation member according to another embodiment of the present invention, and fig. 4b is a sectional view thereof. Fig. 5a is a perspective view showing a core insulation member according to another embodiment of the present invention, and fig. 5b is a sectional view thereof. Fig. 6 is a sectional view showing a core insulation member according to another embodiment of the present invention. Fig. 7a is a front view showing a core insulation member according to another embodiment of the present invention, and fig. 7b is a plan view thereof