CN-121988874-A - Welding method

CN121988874ACN 121988874 ACN121988874 ACN 121988874ACN-121988874-A

Abstract

The invention provides a welding method capable of welding without using a clamp. The welding method is used for welding the terminals of the battery units and the bus bars, and comprises a first step of overlapping the bus bars on the terminals subjected to concave processing in advance, a second step of pressing the bus bars into the positions where the concave processing is arranged, and a third step of welding the terminals and the bus bars. In the second step, a caulking process is performed. Thereby, the bus bar and the terminals are fixed. As a result, the gap during welding can be properly ensured, and thus improvement in welding quality can be expected. Further, since gap inspection is not required, the processing cost can be reduced. Further, since the welding jig pressing at the time of welding is not required, the welding range is widened.

Inventors

SHEN JIANZHI
ISOBE SHUN
SHIBATA NORIHIRO
SHIGENO TAKUMI

Assignees

丰田自动车株式会社

Dates

Publication Date: 20260508
Application Date: 20251104
Priority Date: 20241105

Claims (2)

1. A welding method for welding terminals of battery cells and a bus bar, the welding method characterized by comprising: A first step of superposing the busbar on the terminal subjected to the recess processing in advance; A second step of pressing the bus bar into a position where the concave processing is arranged, and And a third step of welding the terminal and the busbar.
2. The welding method according to claim 1, wherein, And performing riveting processing in the second step.

Description

Welding method Technical Field The invention relates to a welding method. Background In the conventional welding method disclosed in patent document 1 below, a jig presses a bus bar when the bus bar is welded to a terminal of a battery cell. The busbar is pressed against the terminal by the jig and laser welded. Patent document 1 International publication No. 2017/130706 Disclosure of Invention In welding of a bus bar and a terminal of a battery stack, if there is a gap between the bus bar and the terminal, welding failure occurs, and therefore, when the welding is performed while pressing using a pressing jig, it is necessary to perform a dimension measurement of whether or not the gap is formed, and a space for pressing the pressing jig needs to be left on the bus bar side. The present invention has been made to solve the above-described problems. The invention aims to provide a welding method capable of performing welding without using a clamp. The welding method is used for welding the terminals of the battery units and the bus bars, and comprises a first step of overlapping the bus bars on the terminals subjected to concave processing in advance, a second step of pressing the bus bars into the positions where the concave processing is arranged, and a third step of welding the terminals and the bus bars. Effects of the invention According to the present invention, welding can be performed without using a jig. Drawings Fig. 1 is a diagram showing a welding method according to embodiment 1. Fig. 2 is a diagram showing a weldable range in the conventional method and a weldable range in the present embodiment. Fig. 3 is a side view showing a conventional welding method. Fig. 4 is a flowchart showing a conventional process at the time of welding. Fig. 5 is a flowchart showing the steps of the present embodiment at the time of welding. Detailed Description Hereinafter, embodiments will be described with reference to the drawings. In the drawings, common or corresponding elements are denoted by the same reference numerals, and description thereof is simplified or omitted. The configuration shown in the following embodiments represents an example of the technical idea according to the present invention, and may be combined with another known technique, or may be combined with a plurality of technical ideas described in the present invention. Further, a part of the structure may be omitted or changed without departing from the spirit of the present invention. Embodiment 1. Fig. 1 is a diagram showing a welding method according to embodiment 1. As shown in fig. 1, a recess 2 for forming a hole is formed in advance on the upper surface of a terminal 1 of a battery cell. The welding method of the present embodiment is for welding a terminal 1 and a busbar 3, and includes a first step of overlapping a plate-shaped busbar 3 on the terminal 1 having a concave portion 2 formed in the upper surface thereof, a second step of pressing the busbar 3 into a position where the concave portion 2 is arranged, and a third step of welding the terminal 1 and the busbar 3. The second step is performed by caulking. After the bus bar 3 is set in the first step, a caulking process is performed from the upper surface side of the bus bar 3. By the caulking process, a part of the busbar 3 is plastically deformed and enters the inside of the concave process 2. Thereby, the busbar 3 and the terminal 1 are fixed. As a result, the gap during welding can be properly ensured, and thus improvement in welding quality can be expected. Further, since gap inspection is not required, the processing cost can be reduced. Further, since the welding jig pressing at the time of welding is not required, the welding range is widened. Fig. 2 is a diagram showing a weldable range in the conventional method and a weldable range in the present embodiment. As shown in fig. 2, in the conventional method, the welding range is narrow because the welding jig is pressed when welding is required. In contrast, in the case of the present embodiment, since the welding jig pressing at the time of welding is not required, the weldable range is widened. Fig. 3 is a side view showing a conventional welding method. As shown in fig. 3, in the conventional welding method, it is necessary to perform a gap check for measuring the gap between the cell terminal and the bus bar at the time of welding. Fig. 4 is a flowchart showing a conventional process at the time of welding. As shown in fig. 4, in the conventional process, the bus bar 3 is set (step S1), and is pressed with a welding jig (step S2). Next, gap inspection is performed (step S3), and the bus bar 3 is welded (step S4). Fig. 5 is a flowchart showing the steps of the present embodiment at the time of welding. As shown in fig. 5, in the step of the present embodiment, the bus bar 3 is provided (step S11), and the bus bar 3 and the terminals 1 of the battery cells are subjected to caulking processing (step S12). Next, the