JP-2026514263-A - Battery case structure and battery

Abstract

The present invention provides a battery case structure and a battery, the battery case structure comprising a case and a fluid injection assembly provided in the case, the fluid injection assembly comprising a connecting member, a sealing member and a sealing insulating structure, the connecting member being drilled in the case and the cell poles inside the case, the connecting member being provided with fluid injection holes, the sealing member being provided on the connecting member and the sealing insulating structure sealing the inside of the cell. The sealing performance of sealing the fluid injection holes is improved, and when the sealing member seals the fluid injection holes, the case becomes impossible to weld through.

Inventors

• ▲陳▼ ▲劍▼▲偉▼
• 李 文▲亮▼
• ▲楊▼ 新星
• 黄 奕棋
• 李 水源
• ▲劉▼ ▲偉▼
• 郭 元

Assignees

• 孚能科技（▲ガン▼州）股▲フン▼有限公司

Dates

Publication Date

20260508

Application Date

20231027

Priority Date

20230227

Claims (16)

1. The apparatus includes a case and a liquid injection assembly provided in the case, wherein the liquid injection assembly includes a connecting member, a sealing member and a sealing insulating structure, wherein the connecting member is drilled in the case and the cell electrode column inside the case and is used to fix the case and the cell electrode column together, and the connecting member is provided with a liquid injection hole for supplying electrolyte into the cell, The sealing member is provided on the connecting member and is used to seal the liquid injection hole. The sealing and insulating structure is provided between the connecting member and the case, and between the connecting member and the cell pole, and is used to electrically insulate the connecting member from the case and the cell pole, and to seal the inside of the cell. The case and the cell pole are provided with corresponding first and second mounting holes. The connecting member includes a connecting column body, the connecting column body is drilled in the first mounting hole and the second mounting hole, and both ends of the connecting column body are provided with a first flange and a second flange that protrude from the outer circumferential wall of the connecting column body, the first flange is located outside the space enclosed by the case, and the second flange is located inside the space enclosed by the case, and the case and the cell pole column are fixed between the first flange and the second flange. The battery case structure includes the liquid injection hole provided inside the main body of the connecting column.
2. The sealing insulation structure includes a first insulating member, a second insulating member, a third insulating member, and a gasket, wherein the first insulating member is provided between the connecting column body and the case, between the connecting column body and the cell pole column, and between the case and the cell pole column, and is used to electrically insulate the connecting column body, the case, and the cell pole column. The battery case structure according to claim 1, wherein the second insulating member is provided between the case and the first flange and is used to electrically insulate the case and the first flange, the third insulating member is provided between the cell electrode column and the second flange and is used to electrically insulate the cell electrode column and the second flange, and the gasket is provided between the cell electrode column and the second flange and is used to seal the gap between the cell electrode column and the second flange.
3. The first insulating member includes a first insulating portion and a second insulating portion, wherein the first insulating portion is annular and is provided so as to surround the outer circumferential surface of the connecting column body and the first mounting hole, and between the outer circumferential surface of the connecting column body and the hole wall of the second mounting hole. The battery case structure according to claim 2, wherein the second insulating portion is provided between the case and the cell pole and is used to electrically insulate the case and the cell pole.
4. The third insulating member includes an annular third insulating portion and a fourth insulating portion, the third insulating portion being provided between the cell pole and the second flange and surrounding the gasket, The battery case structure according to claim 2, wherein the fourth insulating portion is provided surrounding the outer circumferential surface of the second flange.
5. The second insulating member includes an annular fifth insulating portion and a sixth insulating portion, the fifth insulating portion being provided between the case and the first flange and surrounding the connecting column body, The battery case structure according to claim 2, wherein the sixth insulating portion is provided surrounding the outer circumferential surface of the first flange.
6. The battery case structure according to claim 1, wherein a sealing recess is further provided on the liquid injection end face of the liquid injection hole of the connecting member, the inner diameter of the sealing recess is larger than the opening diameter of the liquid injection hole, and the sealing member is provided in the sealing recess and sealed to the connecting member, and is used to close the liquid injection hole.
7. The battery case structure according to claim 1, wherein the sealing member includes a sealing pin or a sealing ball, and the outer diameter of the sealing pin or sealing ball is larger than the opening diameter of the liquid injection hole.
8. The battery case structure according to claim 7, wherein the sealing pin is a plastic sealing pin.
9. A battery comprising a battery case structure and a cell provided inside the battery case structure, The battery case structure includes a case and a liquid injection assembly provided in the case, the liquid injection assembly includes a connecting member, a sealing member and a sealing insulating structure, wherein the connecting member is drilled in the case and the cell electrode pillars inside the case and is used to fix the case and the cell electrode pillars together, the connecting member is provided with a liquid injection hole for supplying electrolyte into the cell, The sealing member is provided on the connecting member and is used to seal the liquid injection hole. The sealing and insulating structure is provided between the connecting member and the case, and between the connecting member and the cell pole, and is used to electrically insulate the connecting member from the case and the cell pole, and to seal the inside of the cell. The case and the cell pole are provided with corresponding first and second mounting holes. The connecting member includes a connecting column body, the connecting column body is drilled in the first mounting hole and the second mounting hole, and both ends of the connecting column body are provided with a first flange and a second flange that protrude from the outer circumferential wall of the connecting column body, the first flange is located outside the space enclosed by the case, and the second flange is located inside the space enclosed by the case, and the case and the cell pole column are fixed between the first flange and the second flange. A battery is provided in the main body of the connecting column, with the liquid injection hole provided inside.
10. The sealing insulation structure includes a first insulating member, a second insulating member, a third insulating member, and a gasket, wherein the first insulating member is provided between the connecting column body and the case, between the connecting column body and the cell pole column, and between the case and the cell pole column, and is used to electrically insulate the connecting column body, the case, and the cell pole column. The battery according to claim 9, wherein the second insulating member is provided between the case and the first flange and is used to electrically insulate the case and the first flange, the third insulating member is provided between the cell electrode column and the second flange and is used to electrically insulate the cell electrode column and the second flange, and the gasket is provided between the cell electrode column and the second flange and is used to seal the gap between the cell electrode column and the second flange.
11. The first insulating member includes a first insulating portion and a second insulating portion, wherein the first insulating portion is annular and is provided so as to surround the outer circumferential surface of the connecting column body and the first mounting hole, and between the outer circumferential surface of the connecting column body and the hole wall of the second mounting hole. The battery according to claim 10, wherein the second insulating portion is provided between the case and the cell pole and is used to electrically insulate the case and the cell pole.
12. The third insulating member includes an annular third insulating portion and a fourth insulating portion, the third insulating portion being provided between the cell pole and the second flange and surrounding the gasket, The battery according to claim 11, wherein the fourth insulating portion is provided surrounding the outer circumferential surface of the second flange.
13. The second insulating member includes an annular fifth insulating portion and a sixth insulating portion, the fifth insulating portion being provided between the case and the first flange and surrounding the connecting column body, The battery according to claim 12, wherein the sixth insulating portion is provided surrounding the outer circumferential surface of the first flange.
14. The battery according to claim 13, wherein a sealing recess is further provided on the liquid injection end face of the liquid injection hole of the connecting member, the inner diameter of the sealing recess is larger than the opening diameter of the liquid injection hole, and the sealing member is provided in the sealing recess and sealed to the connecting member, and is used to close the liquid injection hole.
15. The battery according to claim 14, wherein the sealing member includes a sealing pin or a sealing ball, and the outer diameter of the sealing pin or sealing ball is larger than the opening diameter of the liquid injection hole.
16. The battery according to claim 15, wherein the sealing pin is a plastic sealing pin.

Description

This application claims priority to Chinese Patent Application No. 202310170007.7, entitled "Battery Case Structure and Battery," filed with the China National Intellectual Property Office on February 27, 2023, and all its contents are incorporated herein by reference. This invention relates to the field of battery manufacturing, and more specifically, to battery case structures and batteries. Currently, with the increasing popularity of new energy vehicles, lithium batteries used in these vehicles are attracting increasing attention. In prismatic lithium batteries, the battery includes a case and a sealing member. An electrolyte injection port is provided in the sheet-like top cover, through which the electrolyte is injected into the lithium battery cells. Existing sealing members seal the electrolyte injection port by direct welding, that is, by welding the sealing member to the case's electrolyte injection port using a laser. On the one hand, laser welding requires a thick case; if the case is thin, it is more prone to through-welding, resulting in battery leakage. On the other hand, the case thickness also affects the battery's energy density; a thicker case reduces the utilization rate of the internal space of the battery, thus decreasing the battery's energy density. Therefore, existing batteries require a high case thickness, making it impossible to reconcile the sealing process requirements for the sealing material with the required energy density of the battery. This is a schematic diagram showing a battery case structure according to an embodiment of the present invention.This is a top view showing a battery case structure according to an embodiment of the present invention. To further clarify the purpose, technical solutions, and advantages of this application, the application will be described in more detail below, along with the drawings and examples. To be understood, the specific examples described herein are for illustrative purposes only and are not intended to limit this application. As those skilled in the art will understand, the singular forms “one,” “one,” “above,” and “the said” as used herein may also include the plural form unless otherwise specified. Furthermore, as will be understood, the term “including” as used in the specification of this invention means the presence of features, integers, steps, operations, elements, modules, and/or assemblies, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, modules, assemblies, and/or combinations thereof. As will be understood, where an element is said to be “connected” or “joined” to another element, it may be directly connected or joined to the other element, or there may be an intermediate element. Furthermore, “connected” or “joined” as used herein may include wireless connection or wireless coupling. The term “and/or” as used herein includes all or any modules of one or more items listed in relation, and all combinations thereof. To the extent that those skilled in the art will understand, all terms used herein (including technical and scientific terms) have the same meaning as generally understood by those skilled in the art unless otherwise defined. Furthermore, to the extent that it will be understood, terms such as those defined in general dictionaries should be understood to have the meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an ideal or overly formal sense unless specifically defined as herein. Figure 1 is a schematic diagram showing a battery case structure according to an embodiment of the present invention. Referring to Figure 1, the battery case structure includes a case 110 and a liquid injection assembly provided in the case 110. The liquid injection assembly includes a connecting member, a sealing member, and a sealing insulation structure. The connecting member is drilled in the case 110 and the cell electrode posts 200 inside the case 110, and is used to integrally fix the case 110 and the cell electrode posts 200. The connecting member is provided with a liquid injection hole 1211 for supplying electrolyte into the cell. The sealing member is provided on the connecting member and is used to seal the liquid injection hole 1211. The cell poles 200 inside case 110 are electrically connected to the cell tabs inside the case and also electrically connected to the cell outer poles outside the case. The sealing and insulating structure is provided between the connecting member and the case 110, and between the connecting member and the cell pole 200. It is used to electrically insulate the connecting member from the case 110 and the cell pole 200, and to seal the inside of the cell. The sealing and insulating structure can fulfill two roles: electrical insulation between the connecting member and the case 110 and the cell pole 200, and internal sealing of the cell. The method by which the sealing memb