CN211743293U

CN211743293U - Firm degree of welding of lithium battery tab detects structure

Info

Publication number: CN211743293U
Application number: CN201921568447.3U
Authority: CN
Inventors: 李世明; 徐秋鹏; 胡庆军; 张叶鑫
Original assignee: Jiangxi Yotteo Auto Technology Co ltd
Current assignee: Jiangxi Yotteo Auto Technology Co ltd
Priority date: 2019-09-20
Filing date: 2019-09-20
Publication date: 2020-10-23
Anticipated expiration: 2029-09-20

Abstract

The utility model discloses a welding firmness degree detection structure of a lithium battery tab, wherein an elastic sheet (4) is arranged between the joint surfaces of a tab (1) and a busbar (2), the end part of the elastic sheet (4) is deep into the position of a welding point, and the position of the welding point is a fusion zone (3); an elastic piece pulling mechanism (5) is arranged on the elastic piece (4), and the pulling direction of the elastic piece pulling mechanism (5) is the direction of separating the lug (1) from the bus bar (2); the tensile force of the elastic sheet pulling mechanism (5) is equal to the standard tensile strength of the welding point. By adopting the technical scheme, the welding firmness degree of the pole lug and the bus bar is reliably tested, and whether the welding meets the requirement or not can be detected; the detection method is simple and easy to implement, can implement full detection, and prevents the occurrence of missed detection of unqualified products.

Description

Firm degree of welding of lithium battery tab detects structure

Technical Field

The utility model belongs to the technical field of electric product manufacturing process equipment. More specifically, the utility model relates to a firm degree of welding of lithium cell utmost point ear detects structure.

Background

In recent years, with the increasing energy and environmental crisis, the development of new energy vehicles becomes a necessary trend, and the performance and safety of power lithium batteries as energy supply devices of new energy vehicles are very important.

At the in-process of module is made to electric core, need weld the utmost point ear of electric core to the busbar on, and the bad phenomenon of utmost point ear and busbar welding often appears in the package welding process. Products with poor welding are put into use, which can cause larger internal resistance, higher temperature and even welding falling in the using process to strike fire, which can cause great influence on the performance and safety of the power battery.

The prior art has the following methods for detecting the welding quality of the lug: resistance test method, tensile test method, and the like. The resistance test method measures the resistance of a welding point, but the static internal resistance can be detected to be over-closed only by slightly welding, and the defect that the welding force can not meet the requirement is overcome; the tensile test in the tensile test method is destructive, so that a sample is scrapped, only can be subjected to sampling inspection, and cannot be subjected to full inspection, so that the missing inspection is easily caused, and the timeliness is not good.

SUMMERY OF THE UTILITY MODEL

The utility model provides a firm degree of welding of lithium battery tab detects structure, its purpose can detect lithium battery tab's welding quality better whether meet the requirements.

In order to realize the purpose, the utility model discloses the technical scheme who takes does:

the utility model discloses a lithium battery tab welded structure for on welding the busbar with the utmost point ear of lithium cell electricity core, the firm degree of welding of utmost point ear detects the structure and is: arranging an elastic sheet between the joint surfaces of the lug and the busbar, wherein the end part of the elastic sheet extends into the position of a welding point, and the position of the welding point is a fusion zone; and the elastic sheet is provided with an elastic sheet pulling mechanism, and the pulling direction of the elastic sheet pulling mechanism is the direction for separating the lug from the bus bar.

The pulling force of the elastic sheet pulling mechanism is equal to the standard tensile strength of the welding point.

In order to realize the same purpose of the invention as the technical scheme, the utility model also provides a method for detecting the welding firmness degree of the lithium battery tab welding structure, the technical scheme is as follows:

the detection method comprises the following detection process steps:

step 1, inserting an elastic sheet between joint surfaces of a tab and a busbar and penetrating into a welding point;

step 2, moving the elastic sheet towards a direction perpendicular to the elastic sheet and enabling the lug to be separated from the busbar through the elastic sheet pulling mechanism until the elastic sheet is completely separated from the lug and the busbar;

and 3, judging whether the welding firmness meets the requirement or not according to the existence or non-existence of damage of the welding point.

The detection standard determining process of the detection method is as follows:

step 1, analyzing the stressed stretching limit and shearing limit of the tab under various conditions through simulation under the specified working condition;

step 2, testing the ratio of the welding shear failure strength to the tensile failure strength;

step 3, converting the shear strength limit obtained by analysis in the step into a tensile strength limit, comparing the tensile strength limit with the tensile strength limit obtained by analysis, and selecting a numerical value as a detection standard;

and 4, manufacturing an elastic sheet, and applying the detection standard tensile strength obtained in the step to the welding point to the maximum extent when the welded pole lug is flatly picked upwards.

By adopting the technical scheme, the welding firmness degree of the pole lug and the bus bar can be reliably tested, and whether the welding meets the requirement can be detected; the detection method is simple and easy to implement, can implement full detection, and prevents the occurrence of missed detection of unqualified products.

Drawings

The contents of the drawings and the reference numbers in the drawings are briefly described as follows:

fig. 1 is a schematic view of a module structure in the present invention;

fig. 2 is a schematic structural view of the positional relationship between the tab and the busbar of the present invention;

fig. 3 is the utility model provides a firm degree of utmost point ear welding detects schematic diagram.

Labeled as:

1. the electrode tab pulling mechanism comprises an electrode tab 2, a bus bar 3, a fusion area 4, an elastic sheet 5 and an elastic sheet pulling mechanism.

Detailed Description

The following detailed description of the embodiments of the present invention will be given with reference to the accompanying drawings for a more complete, accurate and thorough understanding of the inventive concept and technical solutions of the present invention by those skilled in the art.

The utility model discloses a structure as expressed in fig. 1 to fig. 3 is a lithium battery tab welding structure for weld the utmost point ear 1 of lithium battery electricity core to busbar 2. The utility model discloses a lithium battery tab welded structure to and the detection method of the firm degree of utmost point ear welding can detect whether the welding meets the requirements.

In order to overcome the defects of the prior art, the invention aims to better detect whether the welding quality of the pole lug of the lithium battery meets the requirements or not, and the utility model adopts the technical scheme that:

as shown in fig. 1 to fig. 3, the lithium battery tab welding structure of the present invention inserts the elastic sheet 4 between the joint surfaces of the tab 1 and the bus bar 2 during the welding process, and extends into the welding point.

By adopting the technical scheme, the welding firmness degree of the pole lug and the bus bar is reliably tested, and whether the welding meets the requirement or not can be detected; the detection method is simple and easy to implement, can implement full detection, and prevents the occurrence of missed detection of unqualified products.

The specific implementation method comprises the following steps:

the elastic sheet 4 is provided with an elastic sheet pulling mechanism 5, and the pulling direction of the elastic sheet pulling mechanism 5 is the direction of separating the tab 1 from the bus bar 2.

The pulling force of the elastic sheet pulling mechanism 5 is equal to the standard tensile strength of the welding point.

The welding point is a fusion welding area 3.

the process for detecting the welding firmness degree of the 3P small module lug comprises the following steps: :

step 1, inserting an elastic sheet 2 between joint surfaces of a tab 1 and a busbar 2, and penetrating into a welding point;

step 2, moving the elastic sheet 4 towards a direction perpendicular to the elastic sheet 4 and enabling the tab 1 to be separated from the bus bar 2 through the elastic sheet pulling mechanism 5 until the elastic sheet 4 is completely separated from the tab 1 and the bus bar 2;

step 1, analyzing the stressed stretching limit and shearing limit of the tab 1 under various conditions through simulation under a specified working condition;

step 3, converting the shear strength limit obtained by analysis in the step 1 into a tensile strength limit, comparing the tensile strength limit with the tensile strength limit obtained by analysis, and selecting a numerical value as a detection standard;

and 4, manufacturing an elastic sheet 4, and applying the detection standard tensile strength obtained in the step 3 to the welding point to the maximum extent when the welded lug 1 is flatly picked upwards.

The detection technology is that after welding of each minimum module unit is completed, the welding firmness is detected and then the next procedure is performed.

The utility model discloses the firm ultimate tensile strength value of welding is guaranteed in the analysis, uses the flexure strip to apply corresponding tensile strength for the welding point, and the undamaged is qualified promptly, receives the needs rework of destruction. The utility model has the advantages that:

1. a reliable test is given to the welding firmness degree of the lug and the bus bar;

2. the detection is simple and easy to implement, and the full detection can be realized.

The present invention has been described above with reference to the accompanying drawings, and it is obvious that the present invention is not limited by the above-mentioned manner, and various insubstantial improvements can be made without modification to the method and technical solution of the present invention, or the present invention can be directly applied to other occasions without modification, all within the scope of the present invention.

Claims

1. The utility model provides a firm degree of welding detects structure of lithium battery tab which characterized in that: an elastic sheet (4) is arranged between the joint surfaces of the tab (1) and the busbar (2), the end part of the elastic sheet (4) extends into the welding point position, and the welding point position is a fusion joint area (3); an elastic piece pulling mechanism (5) is arranged on the elastic piece (4), and the pulling direction of the elastic piece pulling mechanism (5) is the direction of separating the lug (1) from the bus bar (2); the tensile force of the elastic sheet pulling mechanism (5) is equal to the standard tensile strength of the welding point.