CN117594955A - Welding processing method for battery busbar - Google Patents

Abstract

The utility model relates to the technical field of processing of lead-acid batteries and energy storage batteries, in particular to a battery busbar welding processing method, which comprises the following steps: the battery pack comprises a battery receiving groove, a battery positioning groove, a terminal feeding groove, a lead strip feeding groove, a heating welding groove and a resetting output groove, wherein the polar plate lugs of the battery blank monomers are subjected to pretreatment before being subjected to heating welding, so that the lugs are arranged in a top narrowing shape, and further, when the lugs are connected with a busbar through lead liquid cast welding formed by heating the lead strip in a forming groove, the lead liquid can automatically supplement gaps of the lugs, further, the sufficient connection between the busbar and the lugs is ensured, the service life of the battery during charging and discharging operation is prolonged, the probability of fusing the lugs is reduced, and the improvement of the quality of the battery is promoted.

Description

Welding processing method for battery busbar

Technical Field

The utility model relates to the technical field of processing of lead-acid batteries and energy storage batteries, in particular to a battery busbar welding processing method.

Background

The lead-acid battery, lead-acid storage battery, lead-acid energy storage battery's structure is similar, by the battery case, utmost point crowd, busbar and acid electrolyte are constituteed, utmost point crowd is loaded in the battery case, and the busbar of plumbous matter then is connected utmost point crowd, form the circuit of circulation electric current, current utmost point ear with the busbar carry out cast joint welding processing's mode divide into two modes, one kind utilizes the busbar groove of carving sunken on the metal mould, pour into plumbous liquid into the busbar inslot, afterwards pour into the utmost point ear into the busbar inslot, utilize the cooling channel of predetermineeing on the metal mould, cool off plumbous liquid in the busbar inslot, and then shaping busbar is connected with utmost point ear, then pour into plumbous liquid into the busbar inslot through the cooperation of broach board and locating plate, perhaps place the lead strip in the busbar inslot, make lead strip be heated through the mode of direct heating melt and carry out cast joint with utmost point ear, this kind of processing mode is first, use of lead pot has been reduced, reduce simultaneously the energy consumption, environmental protection is less.

The application is directed to a second bus bar cast welding mode, applicant has previously applied for Chinese patent with patent application number of CN202111404195.2 in 2021 for 11 months and 24 days, and specifically discloses an automatic welding system and a welding method for a lead-acid storage battery, after the blanks of the lead-acid storage battery are input one by one and orderly, the blanks are conveyed along a straight line, and after the flat lead bars and the wiring terminals are clamped by an automatic welding module arranged on a conveying path and heated, bus bar forming work and wiring terminal welding work are automatically completed on the lugs of the blanks of the lead-acid storage battery, automatic welding processing of the lugs of the lead-acid storage battery is realized through the cooperation of a welding device and an automatic grabbing device, and in the whole welding processing process, the heating speed of the lead bars can be automatically adjusted according to thickness difference change of the positive and negative bus bars of the lead-acid storage battery, so that the best energy required by lead bar hot melting is achieved, and the welding quality is high.

However, according to the applicant's self description, in the actual production and use process, since the heating welding gun for heating the lead strip is an argon arc welding gun, and the principle of heating the argon arc welding gun is that an arc is formed between the tungsten electrode and the heating object to release heat, so as to heat the heating object, but the arc of the argon arc welding gun is high in central temperature and low in peripheral temperature, and since the comb plate and the positioning plate positioned at two sides of the tab are all conductive metals, part of current can be led, so that the temperature at the connection position of the two sides of the tab and the bus bar is insufficient in actual production, the lead strip is difficult to melt and cast, the similar ' tooth mark ' virtual welding condition appears at the connection position of the bus bar and two sides of the tab in actual cast welding, and then the connection position of the tab and the bus bar is fused when a large current is passed in the charging and discharging process of a large current, so that the battery is scrapped.

Therefore, in the comparison literature, the applicant also adopts a mode of adjusting the moving speed of the welding gun and further adjusting the heating speed of the lead strip, so that the lead strip is thoroughly hot melted, and the purpose of high-quality welding is achieved, but the actual effect is not satisfactory.

Disclosure of Invention

Compared with the existing cast-on method, the utility model directly gives up the idea of thoroughly hot-melting the lead by adjusting the heating speed of the lead, changes the top shape of the tab to enable the tab to be in a closing-in arrangement from bottom to top, and further enables the middle position of the bus and the top of the tab to be connected during cast-on, thereby avoiding the occurrence of tooth printing cold welding, improving the cast-on quality of the bus and prolonging the service life of the battery.

In order to achieve the above purpose, the present utility model provides the following technical solutions:

a battery busbar welding processing method comprises the following steps:

step a, entering a groove, namely inserting a battery electrode group monomer into a battery groove of a battery shell in a mode that lugs face upwards to form a battery blank monomer, wherein the battery electrode group monomer is formed by stacking positive and negative plates, a separator paper is coated in the middle to form the battery electrode group monomer, the lugs of the positive plates are arranged to form straight rows to be connected with a positive busbar, and the lug arrangement straight rows of the negative plates are connected with a negative busbar;

step b, positioning the battery, namely after the battery blank monomer is clamped and positioned by a welding device, folding the comb plate and the positioning plate in the welding device at the lug of the battery blank monomer to form a forming groove, wherein the lug in the forming groove is narrowed from bottom to top;

c, terminal feeding, namely, grabbing and transferring the wiring terminal to a forming groove through an automatic grabbing device, and locating the wiring terminal and the positive and negative electrodes of the battery blank monomer at the positive and negative electrode positions, wherein the positioning structure of the wiring terminal and the positive and negative electrodes of the battery blank monomer is well described in a comparison document of the background technology;

step d, feeding the lead, namely, grabbing the flattened and cut flat lead by an automatic grabbing device, and transferring the lead to a forming groove for placement;

f, heating and welding, namely, enabling an argon arc welding gun to move at a constant speed along the lead strip to heat the lead strip placed on the forming groove, enabling the lead strip to be heated and melted into lead water, flowing into the forming groove, and forming into a busbar connected with the tab;

and g, resetting and outputting, namely resetting and separating the comb plate from the positioning plate after cooling and molding the lead liquid in the molding groove, and outputting the battery blank monomers.

The battery cast-welding processing method is a cast-welding method formed on the basis of the automatic lead-acid battery welding system described in the literature in the background art, so that the specific structure of cast-welding equipment is not repeated herein, and reference is specifically made to the literature.

The technical thought of this application is, during actual processing, the position of lead bar both sides positive pair tab both sides position is because of the electric current water conservancy diversion, the heat release is not enough can't effectively melt, just change into with tab top width narrowing, when the lead bar is heated and melts cast joint, through the mobility of plumbous liquid, the compensation tab is narrowed and is in the space that the busbar groove formed, and then reach even the tab is narrowed, still can form the welding effect of original setting for width tab, the problem of original tab rosin joint has been eliminated simultaneously, reach the purpose that improves welding quality, simultaneously can not be because of narrowing tab top width, the problem of fusing when leading to the heavy current to pass through.

In the step b, the two ends of the top of the tab are chamfered to form a shape which is narrowed from bottom to top, the size of the chamfer of the top of the tab is 1-2mm, and the chamfer angle is 30-60 degrees.

In the step b, the lug is formed into a shape which is narrowed from bottom to top by rounding the two ends of the top, and the radius of the rounded corner is not smaller than 1.5-3mm.

This polar plate's utmost point ear through the mode that sets up chamfer and fillet at utmost point ear both sides limit, reaches the purpose of narrowing utmost point ear top width to utmost point ear top compares in bottom width can not be too narrow, and the too narrow case, when welder heats the hot melt to the lead, also can lead to the utmost point ear by the hot melt, makes the welding effect of utmost point ear and busbar not reach preset welding width, can lead to on the contrary because of utmost point ear and busbar welding width is not enough, carries out heavy current charge-discharge during operation at the battery, utmost point ear and busbar hookup location department fusing, and the battery is scrapped.

In the step of cutting and brushing, when the electrode lugs are subjected to rolling brushing treatment by a cutting and brushing machine to remove the oxidized surface layer, the electrode lugs are formed into a shape which is narrowed from bottom to top by utilizing the rotary friction of a brush roller.

The electrode plate is purchased by a battery manufacturer, so that the shape of the electrode plate lug is fixed, the shape of the electrode plate lug is a regular strip shape in the market, the width dimension D1 of the top of the electrode plate lug is approximately consistent with the width dimension D2 of the bottom of the electrode plate lug, if the electrode plate is specially customized according to the application, the production cost is improved, the applicant adopts an innovative improvement existing production process, the electrode plate is utilized to carry out a cutting and brushing process on the electrode plate lug before the battery is produced, oxide substances on the surface layer of the electrode plate lug are removed, the welding effect of the electrode plate lug and a bus bar is improved, the electrode plate lug completely conforming to the application can be processed through the existing cutting and brushing process, and the specific structure of the electrode plate cutting and brushing mechanism is shown in the Chinese patent application number CN 202020252909.7.

The specific theory of operation is, remove through perpendicular utmost point ear at the brush roller of current surely brush machine, when carrying out the round brush to utmost point ear, through the rotational speed of adjusting the brush roller, when making the brush roller carry out the round brush to the both sides limit of utmost point ear, the rotational speed of brush roller reduces to 900-1000R/min, utilize the low rotational speed of brush roller and the moment of utmost point ear side contact, carry out round brush processing to utmost point ear top side closed angle, form chamfer or fillet that this application needs, owing to need not to change the structure of current surely brush machine, therefore, this application can accomplish the removal processing to utmost point ear surface oxide layer through surely brush step, can make utmost point ear top form required narrowing shape again, the fillet size of the utmost point ear after this application surely brushes the processing is at R1.5-R3.

In the step f, the argon arc welding gun moves at a constant speed along the lead strip at a speed of 10-25mm/s.

In the step f, the temperature of the center point of the argon arc welding gun is 4000-6000 ℃.

Because the top width dimension of the existing tab is improved, when the bus bar cast-weld processing is carried out, the bus bar is only connected with the top of the tab at the central position, and the vacant position is filled with hot melting thickness lead liquid, so that lead strips at the negative electrode plate can be heated for a long time, the lead strips can achieve good welding effect without being completely melted, and even if the welding gun heats the lead strips at the negative electrode plate, the moving speed of the welding gun is not required to be regulated as described in the background reference specification, the moving speed of the welding gun is required to be regulated, the lead strips at the negative electrode plate are completely melted, and the welding gun can be completely moved at a uniform speed, so that regulation is simpler, and welding quality is also higher.

The utility model has the beneficial effects that:

(1) Compared with the existing cast-welding method, the method directly gives up the idea of thoroughly hot-melting the lead strip by adjusting the heating speed of the lead strip, changes the top shape of the tab into a shape of closing the tab from bottom to top, and further ensures that the bus bar is connected with the middle position of the top of the tab during cast-welding, and the vacant position can be automatically filled by lead liquid, so that the occurrence of tooth printing cold welding is avoided, the cast-welding quality of the bus bar is improved, and the service life of a battery is prolonged;

(2) According to the utility model, when the brush roller of the existing cutting and brushing machine moves through the vertical electrode lug and carries out rolling brushing on the electrode lug of the electrode plate, the rotating speed of the brush roller is regulated, so that when the brush roller carries out rolling brushing on the two side edges of the electrode lug, the rotating speed of the brush roller is reduced to 900-1000r/min, and the sharp angle of the side edge of the top of the electrode lug is subjected to rolling brushing treatment at the moment that the low rotating speed of the brush roller is contacted with the side edge of the electrode lug to form a chamfer or a round angle required by the application;

(3) According to the utility model, the top of the tab is narrowed by changing the size of the top of the tab, so that the change of the sizes of the positive electrode and the negative electrode of the tab is not required to be considered during cast welding of the tab and the busbar, the moving speed of the welding gun is not required to be regulated like a comparison document, and the welding gun can move at a uniform speed, so that high-quality welding of the tab and the busbar can be achieved.

In conclusion, the utility model has the advantages of good busbar welding effect, low battery rejection rate, low production cost and the like, and is particularly suitable for the technical field of cast-weld processing of lead-acid batteries.

Drawings

FIG. 1 is a physical view of a battery busbar prepared by a technical scheme of a background art reference;

FIG. 2 is a physical view of a battery busbar prepared by the cast-on process of the present utility model;

FIG. 3 is a schematic diagram of the process flow of the cast-weld process of the present utility model;

FIG. 4 is a schematic diagram of a plate structure;

FIG. 5 is a schematic diagram of a plate cast-weld structure according to a technical scheme of the background art;

FIG. 6 is an enlarged view of the tab of FIG. 5;

FIG. 7 is a schematic diagram of a fillet tab plate cast-weld configuration of the present utility model;

FIG. 8 is an enlarged view of the tab of FIG. 7;

FIG. 9 is a schematic diagram of a fillet plate cast-weld configuration of the present utility model;

fig. 10 is an enlarged view of the tab in fig. 9.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present utility model, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

Example 1:

taking a 12V20AH lead-acid battery as an example, inserting a battery pole group monomer into a battery groove of a battery shell in a mode that a pole lug faces upwards to form a battery blank monomer;

after the battery blank monomer is clamped and positioned by a welding device, a comb plate and a positioning plate in the welding device are folded at the lug of the battery blank monomer to form a forming groove, the lug in the forming groove is narrowed from bottom to top, two side edges of the top of the lug are cut and brushed by a cutting and brushing machine, round corners with R1.5mm are formed at the two side edges of the lug, and the rotating speed of a brush roller of the cutting and brushing machine is 1000r/min in the cutting and brushing process;

the wiring terminal is grabbed and transferred to the forming groove by an automatic grabbing device and is positioned at the positive and negative electrode positions of the battery blank single body;

after grabbing the flattened and cut flat lead strips by an automatic grabbing device, transferring the lead strips to a forming groove for placement;

the argon arc welding gun moves along the lead at a constant speed to heat the lead placed on the forming groove, so that the lead is heated and melted into lead water, the lead water flows into the forming groove, and is formed into a busbar to be connected with the electrode lugs, wherein the speed of the argon arc welding gun moving along the lead at a constant speed is 10mm/s, and the temperature of the center point of the argon arc welding gun is 4000 ℃;

after the lead liquid in the forming groove is cooled and formed, the comb plate and the positioning plate are reset and separated, and the battery blank monomer is output.

Example 2:

example 2 is different from example 1 in that R2mm rounded corners are formed on two side edges of the tab in example 2, the rotating speed of the brush roller of the brush cutting machine is 950R/min when the brush is cut, the speed of the argon arc welding gun moving along the lead bar at a constant speed is 17mm/s, and the temperature of the center point of the argon arc welding gun is 5000 ℃.

Example 3:

example 3 is different from example 1 in that R3mm rounded corners are formed on two side edges of the tab in example 3, the rotating speed of the brush roller of the brush cutting machine is 900R/min when the brush is cut, the speed of the argon arc welding gun moving along the lead bar at a constant speed is 25mm/s, and the temperature of the center point of the argon arc welding gun is 6000 ℃.

Example 4:

example 4 is different from example 1 in that the tab in example 4 is normally cut and brushed, and the two sides of the top of the tab are chamfered by hand to form a chamfer with a size of 1mm and an angle of 60 °.

Example 5:

example 5 is different from example 2 in that the tab in example 5 is normally cut and brushed, and the two sides of the top of the tab are chamfered by hand to form a chamfer with a size of 1.5mm and an angle of 45 °.

Example 6:

example 6 is different from example 3 in that the tab in example 6 is normally cut and brushed, and the two sides of the top of the tab are chamfered by hand to form a chamfer with a size of 2mm and an angle of 30 °.

Comparative example 1:

comparative example 1 is a welding method of the utility model patent of the background art reference patent application number CN 202111404195.2.

Comparative example 2:

comparative example 2 is different from example 1 in that both side edges of the tab in comparative example 2 form rounded corners of R1mm, and the rotational speed of the brush roll of the brush cutter during brushing is 1100R/min.

Comparative example 3:

comparative example 3 is different from example 3 in that both side edges of the tab in comparative example 3 form rounded corners of R3.5mm, and the rotational speed of the brush roll of the brush cutter is 800r/min when the brush roll is cut.

Comparative example 4:

comparative example 4 was identical to example 4 except that both side edges of the tab top in comparative example 4 were chamfered by hand to form chamfers having a size of 0.9mm and an angle of 60 °.

Comparative example 5:

comparative example 5 was identical to example 6 except that both side edges of the tab top in comparative example 4 were chamfered by hand to form chamfers having a size of 2.1mm and an angle of 30 °.

Comparative example 6:

comparative example 6 was identical to example 4 except that both side edges of the tab top in comparative example 4 were chamfered by hand to form chamfers having a size of 1mm and an angle of 65 °.

Comparative example 7:

comparative example 7 was identical to example 6 except that both side edges of the tab top in comparative example 4 were chamfered by hand to form chamfers having a size of 2mm and an angle of 25 °.

The maximum current charge and discharge operation detection is carried out on the 12V20AH lead-acid batteries processed by the cast welding in examples 1-6 and comparative examples 1-7 respectively, 200 groups of lead-acid batteries are selected in each example, the maximum current charge and discharge cycle is carried out 500 times at the normal temperature of 20 ℃, the internal resistance and the working temperature of the batteries and the fusing rejection rate of the battery bus bars and the polar plate lugs in the discharging process of the lead-acid batteries are counted, and the statistical data are shown in the table I:

firstly, the normal operation of the lead-acid battery with 12V20AH has the cycle times of 300-500, the general cycle times of 350, the battery has the working temperature below 50 ℃ when in charge and discharge, and the service life is reduced due to the negative pole vulcanization capacity loss when the battery is higher than 50 ℃, so the battery is detected by adopting the cycle charge and discharge for 500 times under the maximum current.

Further, the internal resistance of the 12V20AH lead-acid battery is 6-12 milliohms when the battery is charged and discharged at room temperature, the internal resistance of the battery with the tab and the bus bar in a virtual welding mode is higher than 12 milliohms, meanwhile, the working temperature of the virtual welding battery is higher than that of a normal battery due to the increase of the internal resistance when the battery is charged and discharged, and the fusing rejection rate of the corresponding battery is far higher than that of the normal battery after a period of charging and discharging operation.

As is clear from the comparison between examples 1 to 6 and comparative example 1, by adjusting the welding width between the top of the tab and the busbar, even if the two sides of the lead are not completely heat-melted by the arc of the argon arc welding gun, the high quality welding between the tab and the busbar can be ensured by the flow guidance of the heat-melted portion of the lead, whereas in comparative example 1, when the untreated tab and the busbar are welded, the top width is not narrowed, the two sides of the lead are not heat-melted completely after the lead is heated by the argon arc welding gun, and the top of the tab is not provided with any gap, so that the two sides of the tab are directly inserted into the non-heat-melted sides of the lead (the sides are not heat-melted but softened at this time), and a virtual weld is formed (the tab and the busbar formed by the lead are not connected), so that the maximum current is increased during charging and discharging, and the working temperature is increased.

As can be seen from the comparison between examples 1 and 4 and comparative examples 2, 4 and 6, the width of the top of the tab is narrowed, the size of the formed gap cannot be too small, and the gap is too small because the lead liquid is thick metal liquid, the weak fluidity of the lead liquid can cause that the gap is not filled with the lead liquid, so that the gap is not filled with the lead liquid, the part is subjected to cold welding, the internal resistance is further increased, the working temperature is increased, and the battery fusing rejection rate is also increased.

In addition, as can be seen from comparison of examples 3 and 6 with comparative examples 3, 5 and 7, the width of the top of the tab is narrowed, the size of the gap formed cannot be too large, the width of the top of the tab is too small due to the too large gap, the thermal conduction after the molten lead can rapidly lead to the thermal melting of the top of the tab, and further the size of the whole welding part of the tab and the busbar is shortened, the cold welding is caused, the internal resistance is increased, and the battery fusing rejection rate is also increased.

As can be seen from comparison of examples 1-3 and examples 4-6, taking a tab of 12V20AH as an example, the width dimension of the top of the tab is about 7mm, when the tab is narrowed, the rounded corner is formed in a manner of opposite chamfering, the rounded corner is formed in a manner of a circular arc notch, so that lead liquid can flow better to fill the notch of the tab, the rounded corner is arranged in a manner of opposite chamfering, the strength of the tab can be maintained, hot melting caused by heat conduction of the lead liquid can be better avoided, the welding dimension of the tab and a busbar is ensured, and cold welding is avoided.

The foregoing description of the preferred embodiments of the utility model is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the utility model.

Claims (7)

1. The battery busbar welding processing method is characterized by comprising the following steps of:

step a, entering a groove, and inserting a battery electrode group monomer into a battery groove of a battery shell in a mode that a tab faces upwards to form a battery blank monomer;

step b, positioning the battery, namely after the battery blank monomer is clamped and positioned by a welding device, folding the comb plate and the positioning plate in the welding device at the lug of the battery blank monomer to form a forming groove, wherein the lug in the forming groove is narrowed from bottom to top;

c, feeding terminals, wherein the wiring terminals are grabbed and transferred to a forming groove through an automatic grabbing device and are positioned at the positive and negative electrode positions of the battery blank monomers;

step d, feeding the lead, namely, grabbing the flattened and cut flat lead by an automatic grabbing device, and transferring the lead to a forming groove for placement;

f, heating and welding, namely, enabling an argon arc welding gun to move at a constant speed along the lead strip to heat the lead strip placed on the forming groove, enabling the lead strip to be heated and melted into lead water, flowing into the forming groove, and forming into a busbar connected with the tab;

and g, resetting and outputting, namely resetting and separating the comb plate from the positioning plate after cooling and molding the lead liquid in the molding groove, and outputting the battery blank monomers.

2. The battery busbar welding process of claim 1, wherein:

in the step b, the tabs are formed into a shape which is narrowed from bottom to top by chamfering at two ends of the top, the chamfer size of the top of each tab is 1-2mm, and the chamfer angle is 30-60 degrees.

3. The battery busbar welding process of claim 1, wherein:

in the step b, the pole lugs are formed into a shape which is narrowed from bottom to top by rounding the two ends of the top, and the radius of the round corners of the pole lugs is smaller than 1.5-3mm.

4. The battery busbar welding process of claim 1, wherein:

and a cutting and brushing step is further arranged between the step a and the step b, and when the electrode lugs are subjected to rolling brushing treatment by a cutting and brushing machine to remove the oxidized surface layer, the electrode lugs are formed into a shape which is narrowed from bottom to top by utilizing the rotating friction of a brush roller.

5. The battery busbar welding process of claim 4, wherein:

in the cutting and brushing step, the rotating speed of the brush roller is 900-1000r/min.

6. The battery busbar welding process of claim 1, wherein:

in the step f, the constant speed moving speed of the argon arc welding gun along the lead strip is 10-25mm/s.

7. The battery busbar welding process of claim 1, wherein:

in the step f, the temperature of the center point of the argon arc welding gun is 4000-6000 ℃.