EP-4742338-A1 - ASSEMBLING METHOD FOR CYLINDRICAL BATTERY, AND CYLINDRICAL BATTERY

EP4742338A1EP 4742338 A1EP4742338 A1EP 4742338A1EP-4742338-A1

Abstract

The present application relates to the technical field of energy batteries, and discloses a cylindrical battery assembly method and a cylindrical battery. The assembly method includes the following steps: mounting a positive electrode column into a mounting hole in an insulating and sealing manner; arranging a riveting block inside a shell and connecting the riveting block to an outer circumference of a riveting bar of the positive electrode column; connecting a positive electrode current collector plate to a positive electrode tab of an electrode set; placing the electrode set with the positive electrode current collector plate into the shell, and clamping a boss into a groove; welding mating portions of a bottom surface of the groove and a top surface of the boss outside the shell; connecting a negative electrode current collector plate to a negative electrode tab of the electrode set and the shell, to introduce negative electrode current of the electrode set into the shell; and sealing and connecting a negative electrode cover plate to an opening of a second end surface of the shell. The mating between the top surface of the boss and the bottom surface of the groove increases a welding area, and decreases a thickness of the positive electrode column, thereby reducing welding difficulty, improving assembly efficiency, reducing contact internal resistance, increasing the current-carrying capacity of the battery, and improving product yield. The riveting block can increase structural strength of a positive electrode side of a battery cell.

Inventors

YUAN, Yue
LI, JIAN
MA, Yonggui
HOU, Zhanrui

Assignees

SVOLT Energy Technology Co., Ltd.

Dates

Publication Date: 20260513
Application Date: 20240703

Claims (10)

A cylindrical battery assembly method, wherein a cylindrical battery comprises a shell, a positive electrode column, a riveting block, a positive electrode current collector plate, an electrode set, a negative electrode current collector plate, and a negative electrode cover plate; a first end surface of the shell is provided with a mounting hole, a second end surface of the shell is formed with an opening, a side of the positive electrode column that faces an inside of the shell is provided with a groove, a riveting rib is formed on a circumference of the groove, and a side of the positive electrode current collector plate that faces the positive electrode column is provided with a boss; the assembly method comprises the following steps: mounting the positive electrode column into the mounting hole in an insulating and sealing manner; arranging the riveting block inside the shell and connecting the riveting block to an outer circumference of the riveting rib of the positive electrode column; connecting the positive electrode current collector plate to a positive electrode tab of the electrode set; placing the electrode set with the positive electrode current collector plate into the shell, and clamping the boss into the groove; and welding mating portions of a bottom surface of the groove and a top surface of the boss from outside the shell.
The cylindrical battery assembly method as claimed in claim 1, wherein the arranging the riveting block inside the shell and connecting the riveting block to an outer circumference of the riveting rib of the positive electrode column specifically comprises: fitting the riveting block to an outer circumference of the positive electrode column, allowing the riveting rib to pass through a through hole on the riveting block; and/or bending the riveting rib outwards from the groove, to insert the riveting rib into a mounting groove of the riveting block.
The cylindrical battery assembly method as claimed in claim 2, wherein the positive electrode column comprises a limit protrusion located outside the shell and the riveting rib located inside the shell, the limit protrusion and the riveting rib limit two ends of the positive electrode column respectively, and the mounting the positive electrode column into the mounting hole in an insulating and sealing manner specifically comprises: arranging a sealing member to abut against an outer wall of the positive electrode column and an inner wall of the mounting hole; arranging an upper insulating member between the limit protrusion and an outer surface of the shell; and arranging a lower insulating member on an inner surface of the shell, and allowing the riveting block to abut against the lower insulating member.
The cylindrical battery assembly method as claimed in claim 3, wherein the arranging an upper insulating member between the limit protrusion and an outer surface of the shell specifically comprises: wrapping an outer circumference of the limit protrusion with a first insulating portion of the upper insulating member; and arranging a second insulating portion of the upper insulating member between a bottom surface of the limit protrusion and the outer surface of the shell.
The cylindrical battery assembly method as claimed in claim 4, wherein the arranging a sealing member to abut against an outer wall of the positive electrode column and an inner wall of the mounting hole specifically comprises: arranging a first sealing portion of the sealing member to abut against the outer surface of the shell and the bottom surface of the limit protrusion, and allowing an end of the first sealing portion to abut against the second insulating portion; and arranging a second sealing portion of the sealing member to abut against the outer wall of the positive electrode column and the inner wall of the mounting hole, and allowing an end of the second sealing portion to abut against the lower insulating member.
The cylindrical battery assembly method as claimed in any one of claims 1 to 5, wherein the clamping the boss into the groove specifically comprises: rounding an opening of the groove to form a chamfer, and clamping the boss into the groove through the chamfer.
The cylindrical battery assembly method as claimed in any one of claims 1 to 5, wherein the welding mating portions of a bottom surface of the groove and a top surface of the boss from outside the shell specifically comprises: forming a welding slot on a top surface of the positive electrode column, with the welding slot corresponding to the groove; and welding the mating portions of the bottom surface of the groove and the top surface of the boss through the welding slot from outside the shell.
The cylindrical battery assembly method as claimed in any one of claims 1 to 5, further comprising: connecting the negative electrode current collector plate to a negative electrode tab of the electrode set and the shell, to introduce negative electrode current of the electrode set into the shell.
The cylindrical battery assembly method as claimed in claim 8, further comprising: sealing and connecting the negative electrode cover plate to the opening of the second end surface of the shell.
A cylindrical battery assembled using the cylindrical battery assembly method as claimed in any one of claims 1 to 9, comprising: a shell, wherein a first end surface of the shell is provided with a mounting hole, and a second end surface of the shell is formed with an opening; an electrode set arranged in the shell; a positive electrode column mounted in the mounting hole in an insulating and sealing manner, wherein a side of the positive electrode column that faces an inside of the shell is provided with a groove, and a riveting rib is formed on a circumference of the groove; a riveting block arranged in the shell and connected to an outer circumference of the riveting rib; a positive electrode current collector plate connected to a positive electrode tab of the electrode set, wherein a side of the positive electrode current collector plate that faces the positive electrode column is provided with a boss, and the boss is clamped into the groove; a negative electrode current collector plate connected to a negative electrode tab of the electrode set and the shell; and a negative electrode cover plate sealed at the opening of the second end surface of the shell.

Description

CROSS REFERENCE TO RELATED APPLICATION The present application claims priority to Chinese Patent Application No. 2023108076506 filed with the China National Intellectual Property Administration on July 3, 2023, and entitled "CYLINDRICAL BATTERY ASSEMBLY METHOD AND CYLINDRICAL BATTERY", which is incorporated herein by reference in entirety. TECHNICAL FIELD The present application relates to the technical field of cylindrical batteries, and specifically relates to a cylindrical battery assembly method and a cylindrical battery. BACKGROUND ART Cylindrical batteries have become one of the important research directions for power batteries used in new energy vehicles due to their high energy density, high safety, and low cost. A cylindrical battery mainly includes a shell, a roll core, a positive cover plate, a negative cover plate, a positive electrode column, a positive current collector plate, and a negative electrode current collector plate, where a first end of the shell is open, an end surface of a second end of the shell is provided with a mounting hole, the roll core is arranged in the shell, the negative cover plate seals the first end of the shell, the positive electrode column is mounted in the mounting hole, and the positive current collector plate is configured to be connected to a positive electrode tab of the roll core and the positive electrode column. In the prior art, the connection between the positive current collector plate and the positive electrode column is usually achieved by a resistance welding pin that passes through a central through hole of the roll core to weld an adapter and the electrode column from the inside of the shell. The limited space within the central through hole of the roll core leads to small welding area and high welding difficulty. In addition, influenced by the thickness of the positive electrode column, post-welding current contact internal resistance is relatively high, which consequently affects the current-carrying capacity of the battery. SUMMARY In view of this, the present application provides a cylindrical battery assembly method and a cylindrical battery, to solve the problem that the current-carrying capacity of existing cylindrical batteries is affected by small welding area, high welding difficulty, and high post-welding current contact internal resistance. In a first aspect, the present application provides a cylindrical battery assembly method, where a cylindrical battery includes a shell, a positive electrode column, a riveting block, a positive electrode current collector plate, an electrode set, a negative electrode current collector plate, and a negative electrode cover plate; a first end surface of the shell is provided with a mounting hole, a second end surface of the shell is formed with an opening, a side of the positive electrode column that faces an inside of the shell is provided with a groove, a riveting rib is formed on a circumference of the groove, and a side of the positive electrode current collector plate that faces the positive electrode column is provided with a boss; the assembly method includes the following steps: mounting the positive electrode column into the mounting hole in an insulating and sealing manner;arranging the riveting block inside the shell and connecting the riveting block to an outer circumference of the riveting rib of the positive electrode column;connecting the positive electrode current collector plate to a positive electrode tab of the electrode set;placing the electrode set with the positive electrode current collector plate into the shell, and clamping the boss into the groove; andwelding mating portions of a bottom surface of the groove and a top surface of the boss from outside the shell. Beneficial effect: The positive electrode column is mounted into the mounting hole on the first end surface of the shell in the insulating and sealing manner, to achieve mutual insulating and sealing fixed connection between the positive electrode column and the shell; the boss of the positive electrode current collector plate is clamped into the groove of the positive electrode column, and the mating portions of the top surface of the boss and the bottom surface of the groove are welded, to achieve welding fixation between the boss and the groove; the mating between the top surface of the boss and the bottom surface of the groove increases welding area, and the groove decreases a welding thickness of the positive electrode column, thereby reducing welding difficulty, improving assembly efficiency, reducing contact internal resistance, increasing the current-carrying capacity of the battery, and improving product yield; and the riveting block is arranged on the outer circumference of the riveting rib to increase structural strength of a positive electrode side of a battery cell. In an optional implementation, the arranging the riveting block inside the shell and connecting the riveting block to an outer circumference of