CN213520071U

CN213520071U - Battery welded without electrode lug

Info

Publication number: CN213520071U
Application number: CN202022883408.1U
Authority: CN
Inventors: 潘青海
Original assignee: Doxter Tianjin New Energy Technology Co ltd
Current assignee: Doxter Tianjin New Energy Technology Co ltd
Priority date: 2020-12-05
Filing date: 2020-12-05
Publication date: 2021-06-22
Anticipated expiration: 2030-12-05

Abstract

The utility model provides a no polar ear welded battery, include the shell and the electric core that constitutes by positive plate, negative pole piece and diaphragm, the shell bottom is equipped with protruding weld groove, and protruding weld groove inlays to exerted positive negative pole mass flow body in, positive negative pole mass flow body and shell laser welding layer, and the laser welding layer adopts the positive negative pole mass flow body of laser welding and obtains with the shell, and the laser welding layer sets up the thinnest department at protruding weld groove. The utility model discloses a to optimizing with positive negative pole mass flow body direct contact's battery case bottom and battery cover top cap's improvement, increased area of contact between them and firm nature, rethread direct welded mode has strengthened welding effect between the two simultaneously, has higher practical value.

Description

Battery welded without electrode lug

Technical Field

The utility model relates to a battery field, concretely relates to electrodeless ear welded battery.

Background

Along with the rapid increase of the demand of the current market for the battery, the requirement on the battery is higher and higher, and in order to meet the market demand, various large manufacturers continuously design and transform the battery from the aspects of improving the energy density of the battery, reducing the cost of the battery, improving the large-current charging and discharging capacity of the battery and the like. The most common and mainstream design of the battery is 'no electrode lug' or 'full electrode lug', wherein one of the designs is to increase the internal space of the battery to improve the capacity, a direct close contact or direct welding mode of a positive electrode current collector and a negative electrode current collector with a battery shell is adopted, and a welding mode of the positive electrode current collector and the negative electrode current collector, namely 'a cover plate' (a current collecting plate) and the battery shell is abandoned, so that although the internal space of the battery is increased to improve the energy, the structure and the technology of the close contact mode and the direct welding mode have some defects. Firstly, the contact mode of the positive and negative current collectors and the battery shell is compact, gaps still exist, and meanwhile, in the use process, due to the complex use condition of the battery, the generation of the gaps is increased continuously, so that the internal resistance of the battery is unstable, the loss of the electric energy output and input of the battery is large, and the quick charge, the heavy current discharge and the service life of the battery are influenced; secondly, the positive and negative current collectors and the battery shell are directly welded, so that problems are essentially avoided, and in actual use, the thicker the thickness of the material at the welding position of the battery shell is, the poorer the welding effect is, and even insufficient welding or incomplete welding can be caused, so that the internal resistance of the battery is unstable.

In order to solve the above problems, how to ensure reliable welding between the positive and negative electrode current collectors and the battery case is a main improvement direction of the problem.

SUMMERY OF THE UTILITY MODEL

The utility model provides a no polar ear welded battery improves on positive negative pole mass flow body and the direct welded basis of battery case, optimizes the welding effect, reduces the welding internal resistance.

Realize the technical scheme of the utility model is that:

the utility model provides a no ear welded battery, includes the shell and by the electric core that positive plate, negative pole piece and diaphragm constitute, the shell bottom is equipped with protruding weld groove, and protruding weld groove inlays to in the positive negative current collector that exposes, positive negative current collector and shell laser welding layer, and laser welding layer adopts laser welding positive negative current collector and shell to obtain, and the laser welding layer sets up the thinnest department at protruding weld groove.

Preferably, the housing comprises a main housing (battery housing) with an opening at the top and a connecting housing (battery cover) mechanically sealed at the opening at the top of the main housing, and the main housing (battery housing) is cylindrical or square; the connecting shell (battery cover) comprises at least one metal piece and an insulating piece.

The protruding weld groove is towards the direction punching setting of positive negative current collector.

The projection welding groove is not punched through, and the thinnest thickness of the projection welding groove is controlled to be 0-0.2 mm. When welding the positive and negative electrode fluids and the outer shell, the positive and negative electrode current collectors are fully contacted with the bottom of the battery shell or the top cover of the battery cover by certain pressure, the convex grooves of the positive and negative electrode current collectors are directly embedded into the exposed positive and negative electrode current collectors, and then the thinnest positions of the convex grooves are directly welded by laser to enable the positive and negative electrode current collectors and the outer shell to be tightly welded.

The protruding welding groove is punched and arranged, and the thinnest thickness of the protruding welding groove is controlled to be 0 mm. Then, placing the same or fused metal materials as the current collectors of the positive electrode and the negative electrode at the breakdown position, wherein the metal materials placed at the positive electrode end comprise but are not limited to aluminum, aluminum alloy, tin and the like; the metal material disposed at the negative electrode terminal includes, but is not limited to, copper alloy, nickel alloy, tin, etc. When welding the positive and negative electrode fluids and the outer shell, the positive and negative electrode current collectors are fully contacted with the bottom of the battery shell or the top cover of the battery cover by certain pressure, the raised welding grooves can be directly embedded into the exposed positive and negative electrode current collectors, and then the metal material is placed for direct laser welding, so that the positive and negative electrode current collectors and the outer shell are tightly welded without leakage.

Preferably, the punching part of the protruding welding groove is provided with a metal wire, and laser welding is directly carried out at the position where the metal wire is placed during welding, so that the positive and negative current collectors are tightly welded with the shell without leakage.

The positive plate and the negative plate respectively comprise a coating area and a blank area, and the edge of the blank area exceeds the edge of the diaphragm. The material-free regions (blank) of the positive plate and the negative plate are respectively in direct contact with the main shell (battery shell) and the top cover connected with the shell (battery cover).

The height of the punched protruding welding groove cannot be higher than the blank width of the corresponding positive and negative current collectors, so that the battery short circuit is prevented from being caused in the manufacturing process.

Preferably, the number and the arrangement shape of the protruding welding grooves can be controlled by self, the shapes and the number of the protruding welding grooves can be flexibly arranged according to actual needs, and the welding grooves with more contact points and firmness are formed.

The preparation method of the battery welded without the electrode lug comprises the following steps:

(a) coating active substances on a metal foil according to the process proportion of a positive electrode and a negative electrode on the metal foil, and respectively obtaining a positive electrode sheet and a negative electrode sheet with one edge forming a blank region after slitting;

(b) sequentially laminating the diaphragm, the positive plate and the negative plate, and then forming a winding core in a winding or stacking mode, wherein one ends of the positive plate and the negative plate, which are provided with the blank regions, are respectively arranged at the outer sides of the two long edges of the diaphragm, and the blank exceeds the outer side of the edge of the diaphragm;

(c) performing early processing treatment on the shell to enable the part of the shell facing to the direction of the positive and negative current collectors to be stamped with a convex welding groove to form a welding convex groove;

(d) placing the roll core in a shell, fully contacting the positive and negative current collectors with the shell under certain pressure, directly embedding the raised welding grooves in the exposed positive and negative current collectors, and then directly welding the raised welding grooves by laser to enable the positive and negative current collectors to be tightly welded;

(e) sealing the battery, vacuumizing and injecting electrolyte into the liquid injection port, sealing, and carrying out formation and volume grading processes to obtain the battery without the electrode lugs.

The number of the protruding welding grooves is set to be a plurality.

The utility model has the advantages that: the utility model discloses a to optimizing with positive negative pole mass flow body direct contact's battery case bottom and battery cover top cap's improvement, increased area of contact between them and firm nature, rethread direct welded mode has strengthened welding effect between the two simultaneously, has higher practical value.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic side sectional view of the convex groove of the present invention without direct punching;

fig. 2 is a schematic structural view of the direct punching of the convex groove of the present invention;

FIGS. 3-1 to 3-6 are shape diagrams of the arrangement and welding effect of the convex grooves of the present invention;

FIG. 4 is a schematic diagram of the structure of the positive and negative electrodes in the embodiment of the present invention;

FIG. 5 is a schematic view of a roll core structure in an embodiment of the present invention;

fig. 6 is a schematic structural view of an electrode-less ear battery according to an embodiment of the present invention;

fig. 7 is a schematic structural view of an electrode-less ear battery of the present invention, which is not welded in the comparative example.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without any creative effort belong to the protection scope of the present invention.

As shown in fig. 5, a non-tab welded battery includes a housing 10 and a battery core composed of a positive tab 501, a negative tab 503, and a separator 502, where the positive tab 501 and the negative tab 503 both include a coating area 402 and a blank area 401 (fig. 4), the edge of the blank area 401 exceeds the edge of the separator 502, a protruding weld groove 100 is disposed at the bottom of the housing 10, the protruding weld groove 100 is embedded in an exposed positive and negative current collector 102, the positive and negative current collectors are laser welded to the housing 10, the laser welded layer is disposed at the thinnest position of the protruding weld groove 100, and the height of the protruding weld groove 100 cannot be greater than the width of the blank area 401.

Preferably, the projection weld recesses 100 are punched toward the positive and negative electrode current collectors 102.

Preferably, as shown in fig. 1, the projection weld recesses 100 are not punched through, and the thinnest thickness of the projection weld recesses 100 is controlled to be 0-0.2 mm.

Preferably, as shown in fig. 2, the projection weld recesses 100 are punched through, and the thinnest thickness of the projection weld recesses 100 is controlled to be 0 mm. The punching part of the convex welding groove 100 is provided with a metal wire 101, and a laser welding layer is arranged at the position where the metal wire 101 is placed, so that the positive and negative current collectors 102 are tightly welded with the shell 10 without leakage.

Example 1

A preparation method of a non-lug welding battery comprises the following steps:

(a) preparing a cylindrical 32650 battery without a tab, coating active substances on a foil according to the process proportion of a positive electrode and a negative electrode on the foil to form a coating area 402, and cutting to obtain a positive electrode plate 501 and a negative electrode plate 503 with a blank area 401 formed on one side, wherein the blank width of the positive electrode and the negative electrode is 4 +/-0.5 mm, and the blank width is shown in figure 4;

(b) the diaphragm 502 and the anode and the cathode are sequentially stacked to form a winding core 500 in a winding or stacking mode, wherein the winding core comprises an anode end 504 and a cathode end 505, the ends of the anode sheet and the cathode sheet provided with the blank areas are respectively arranged on the outer sides of two long edges of the diaphragm, and the blank areas 401 exceed the outer sides of the edge of the diaphragm 502, as shown in fig. 5;

(c) the method comprises the following steps of carrying out early-stage processing on a main shell (battery shell) to enable the part of the main shell facing the direction of a negative current collector to be punched with a protruding weld groove 100 (figure 1), wherein the part of the main shell facing the direction of the negative current collector is uniformly divided into four parts at a position 3mm away from the center of the bottom of the battery shell by taking the center of the bottom of the battery shell as a reference, the four parts are punched into the weld groove in the shape of figure 3-1 (in the figure 3-1, two transverse lines are formed by connecting a plurality of adjacent protrusions together to form a wire groove, the protrusions are small, and the;

because the middle of the winding core is hollow (a dotted line circle in the middle of the figures 3-1 to 3-6), the middle part is avoided when the protruding welding groove is arranged, and the protruding welding groove can be arranged according to the figures of the figures 3-1 to 3-6;

(d) the punching highest point height of the welding groove is 2.0 +/-0.1 mm (the highest point height of the welding groove is less than the width of the blank of the positive electrode and the negative electrode), the welding groove cannot be punched through, and the thinnest thickness of the welding groove is controlled to be 0.1 +/-0.05 mm to form a convex welding groove;

(e) placing the winding core in a main shell (battery case), fully contacting the negative current collector with the bottom of the battery case with a certain pressure, simultaneously enabling the convex welding groove 100 to be directly embedded in the exposed negative current collector, and then directly welding the convex groove by laser to enable the convex groove and the convex groove to be tightly welded, as shown in fig. 6 a;

(f) placing a connecting shell (battery cover) on the opening side of a main shell (battery shell), fully contacting the battery cover with a positive current collector by using certain pressure, tightly welding the connecting shell and the positive current collector by using laser welding, and sealing the battery;

(g) vacuumizing and injecting electrolyte at the liquid injection port and then sealing;

(h) after the manufacturing is finished, the battery without the pole lug is manufactured through the working procedures of formation, capacity grading and the like.

Example 2

(b) the diaphragm 502 and the anode and the cathode are sequentially stacked to form a winding core in a winding or stacking mode, the ends of the anode sheet and the cathode sheet, which are provided with the blank, are respectively arranged at the outer sides of the two long sides of the diaphragm, and the blank area 401 exceeds the outer side of the edge of the diaphragm 502, as shown in fig. 5;

(c) the method comprises the following steps of carrying out early-stage processing on a main shell (battery shell) to enable the part of the main shell facing the direction of a negative current collector to be punched with a protruding weld groove 100, wherein the center of the bottom of the battery shell is taken as a reference, four parts are evenly arranged at a position 3mm away from the center of the bottom, the punched weld groove is in a shape of a graph 3-1 (two transverse lines in the graph 3-1 are formed by connecting a plurality of adjacent protrusions, the protrusions are small, and the specification of the weld groove is 2mm wide by 10mm long (error +0.05 mm);

because the middle of the winding core is hollow (a dotted line circle in the middle of the figures 3-1 to 3-6), the middle part is avoided when the protruding welding groove is arranged, and the protruding welding groove can be arranged according to the figures of the figures (3-1 to 3-6);

(d) punching the welding groove (figure 2) with the highest punching point height of the welding groove being 2.0 +/-0.1 mm (the highest punching point height of the welding groove is less than the width of the blank of the positive electrode and the negative electrode), and controlling the thinnest thickness of the welding groove to be 0mm to form a convex welding groove; meanwhile, copper wires are embedded in the raised welding grooves 100, and the specification of the copper wires is 2mm wide by 10mm long (error is-0.5 mm);

(e) placing the roll core in the main shell (battery case), fully contacting the negative current collector with the bottom of the battery case with a certain pressure, simultaneously enabling the convex welding groove 100 to be directly embedded into the exposed negative current collector, and then directly welding the copper wire embedded in the convex groove by laser to enable the copper wire and the convex groove to be tightly welded, as shown in fig. 6 b;

Comparative example 1

A method for preparing a non-welding electrode-less lug comprises the following steps:

1. preparing a cylindrical 32650 battery without a tab, coating active substances on a metal foil according to the process proportion of a positive electrode and a negative electrode, and cutting to obtain a positive electrode sheet and a negative electrode sheet with left white on one side, wherein the left white width of the positive electrode and the negative electrode is 4 +/-0.5 mm, and the left white width is shown in figure 4;

2. sequentially laminating the diaphragm and the anode and the cathode, and then forming a winding core in a winding or stacking mode, wherein the ends, provided with the blank, of the anode sheet and the cathode sheet are respectively arranged at the outer sides of the two long sides of the diaphragm, and the blank exceeds the outer side of the edge of the diaphragm, as shown in figure 5;

3. placing the winding core in the main shell (battery shell), and fully contacting the negative current collector with the bottom of the battery shell with certain pressure, as shown in fig. 7;

4. injecting an electrolyte into the main housing;

5. placing a connecting shell (battery cover) at the opening side of a main shell (battery shell), fully contacting the battery cover with a positive current collector by using certain pressure, and then sealing the battery;

6. after the manufacturing is finished, the battery without the pole lug is manufactured through the working procedures of formation, capacity grading and the like.

The performance of the electrode-less ear batteries prepared in the above-mentioned examples 1 and 2 and comparative example 1 was tested, and the test results are shown in table 1, and the test method was a method conventional in the art.

Figure DEST_PATH_518871DEST_PATH_IMAGE002

Can know by last table, with the comparative example, according to the utility model discloses the no utmost point ear battery of method preparation plays the internal resistance and obviously stabilizes, and the pole piece mass flow body is firm with the casing welding, and the contact is inseparable, has guaranteed the stability of battery performance.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a no ear welded battery, includes shell (10) and by positive plate (501), negative pole piece (503) and diaphragm (502) the electric core that constitutes, its characterized in that: the battery is characterized in that a protruding welding groove (100) is formed in the bottom of the shell (10), the protruding welding groove (100) is embedded into an exposed positive and negative current collector (102), the positive and negative current collector and the shell (10) are welded by laser, and the laser welding layer is arranged at the thinnest position of the protruding welding groove (100).

2. The electrode less ear welded battery of claim 1, wherein: the protruding weld groove (100) is punched towards the positive and negative current collectors (102).

3. The electrode less ear welded battery of claim 1, wherein: the projection welding groove (100) is not punched through, and the thinnest thickness of the projection welding groove (100) is controlled to be 0-0.2 mm.

4. The electrode less ear welded battery of claim 1, wherein: the protruding welding groove (100) is punched and arranged, and the thinnest thickness of the protruding welding groove (100) is controlled to be 0 mm.

5. The electrode less ear welded battery of claim 4, wherein: the punching-through position of the protruding welding groove (100) is provided with a metal wire (101), and a laser welding layer is arranged at the position where the metal wire (101) is placed, so that the positive and negative current collectors (102) and the shell (10) are tightly welded without air leakage.

6. A electrodeless ear welded battery as claimed in any of claims 1 to 5, wherein: the positive plate (501) and the negative plate (503) both comprise a coating area (402) and a blank area (401), and the edge of the blank area (401) exceeds the edge of the diaphragm (502).

7. The electrode less ear welded battery of claim 6, wherein: the height of the protruding welding groove (100) cannot be higher than the width of the white space (401).