Lithium-ion battery current collector welding equipment

Abstract

This invention provides a lithium-ion battery current collector welding device, comprising a base with an internal mounting groove extending upwards and penetrating the upper surface of the base, and a downwardly extending storage groove on the lower side of the mounting groove; a conveying mechanism disposed within the mounting groove; a driving mechanism disposed on the outer wall of the base for driving the conveying mechanism; battery assembly supports arranged on the conveying mechanism for supporting lithium battery cells and lithium battery tabs, or for supporting lithium battery composite current collector electrodes and current collector metal adapter plates; and a mounting frame disposed on the upper surface of the base, the inner side of which is equipped with a welding mechanism via a telescopic mechanism for welding lithium battery cells and lithium battery tabs or lithium battery composite current collector electrodes and current collector metal adapter plates. This invention enables circular laser welding of welding positions at multiple angles, multiple points, and equal or unequal spacing.

Description

Technical Field

[0001] The invention relates to the technical field of lithium battery tab welding, and in particular to a lithium ion battery current collector welding device. Background Art

[0002] Tabs are a component of traditional lithium-ion polymer battery products. Batteries are divided into positive and negative electrodes. Tabs are metal conductors that lead the positive and negative electrodes out of the battery core. Generally speaking, the tabs of the positive and negative electrodes of the battery are the contact points during charging and discharging. Tabs are divided into three types of materials. The positive electrode of the battery uses aluminum (Al) material, the negative electrode uses nickel (Ni) material, and the negative electrode also has copper-plated nickel (NiCu) material. They are all composed of two parts: film and metal strip. The film is the insulating part of the tab. Its purpose is to prevent short circuits between the metal strip and the aluminum-plastic film when the battery is packaged, and to heat (about 140°C) to hot-melt seal and bond with the aluminum-plastic film to prevent leakage during packaging.

[0003] In the prior art, the pole ear is generally welded to the current collector of the battery cell plate by ultrasonic zone welding or laser linear welding. The existing welding method requires welding one by one, and machine or manual picking and placing are required before and after welding, which takes up picking and placing time and has low efficiency. It is also impossible to realize the circular welding laser welding process of multiple equally spaced or unequally spaced welding positions.

[0004] Composite current collector is a new type of composite material. It is a three-layer structure with a middle layer of polymer (PET, PI, etc.) and a metal layer (copper foil, aluminum foil, nickel foil, etc.) on the top and bottom. The advantage of using this current collector is that it can greatly improve the safety of the battery and reduce the weight of the battery. However, there are some problems in the use of this type of current collector: the metal layers on both sides of the composite foil are often relatively thin (50nm-2000nm), and due to the partition of the intermediate polymer layer, the pole ear and the battery electrode cannot be directly welded. Therefore, the current collectors on both sides of each battery electrode need to be spliced ​​with metal adapters for welding. After multiple battery electrodes are stacked or wound, the metal adapters of the overlapping multiple electrodes are welded to the pole ears. However, the traditional welding process for lithium-ion battery electrodes uses ultrasonic welding to weld the pole collector to the pole ear or the metal adapter. Under the pressure of the ultrasonic welding head, the polymer layer of the composite current collector avoids and easily forms a weld with a void in the middle, reducing the current conduction area and poor current carrying capacity, resulting in an increase in the internal resistance of the electrode, and the welding pressure is not easy to control, or multiple layers of battery electrodes are welded through and then welded to the pole ears. The welding interface between the pole ears and the battery electrodes is not firm, and it is easy to desolder during subsequent use, causing safety accidents. Therefore, in order to further optimize the firmness and reliability of the welding position, it is particularly important to realize the circular welding mark laser welding process and the equipment to realize multiple welding positions with equal or unequal spacing. Summary of the invention

[0005] The present invention provides a lithium ion battery current collector welding device, which is used to solve the defect in the prior art that the current collector assembly needs to be machined or manually taken and placed before and after welding, which takes up the time for taking and placing, and realizes high-efficiency welding of the battery current collector.

[0006] The present invention provides a lithium ion battery current collector welding device, comprising:

[0007] A base, wherein a mounting groove is formed inside the base, the mounting groove extends upward and penetrates the upper surface of the base, and the lower side of the mounting groove extends downward to form a storage groove;

[0008] A transmission mechanism is arranged in the installation groove;

[0009] A driving mechanism, disposed on the outer side wall of the base, for driving the conveying mechanism;

[0010] A battery assembly support, arranged on the conveying mechanism, for carrying lithium battery cells and lithium battery tabs, or for carrying lithium battery composite current collector pole pieces and current collector metal adapter sheets;

[0011] The mounting frame is arranged on the upper surface of the base, and a welding mechanism for welding the lithium battery cell and the lithium battery pole ear or the lithium battery composite current collector pole piece and the current collector metal adapter piece is arranged on the inner side of the mounting frame through a telescopic mechanism.

[0012] According to a lithium-ion battery current collector welding device provided by the present invention, the conveying mechanism includes a plurality of rollers rotatably arranged in the mounting groove, and a conveyor belt is sleeved on the outside of the plurality of rollers.

[0013] According to a lithium-ion battery current collector welding device provided by the present invention, the driving mechanism includes a driving motor, a driving pulley and a driven pulley, the driving motor is installed on the outer side wall of the base, the output end of the driving motor is installed with the driving pulley, one end of the rotating roller extends to the outside of the base and is installed with the driven pulley, and the driving pulley and the driven pulley are connected by a belt.

[0014] According to a lithium-ion battery collector welding device provided by the present invention, the battery assembly support includes two symmetrically arranged L-shaped folding plates, the L-shaped folding plates are fixed on the conveyor belt, and side baffles are arranged on both sides of the L-shaped folding plates. A battery assembly installation space is formed between the two L-shaped folding plates and the side baffles arranged on the L-shaped folding plates. The lithium battery cell or the lithium battery composite collector electrode sheet is installed in the battery assembly installation space, and an upwardly inclined current collector support plate is arranged on the side baffle on one side, and a bonding and fixing adhesive layer for fixing the lithium battery electrode ear or a fixed compression strip for fixing the current collector metal adapter sheet is arranged on the current collector support plate.

[0015] According to a lithium-ion battery current collector welding device provided by the present invention, the welding mechanism includes a rotating motor arranged at the bottom of the telescopic end of the telescopic mechanism, and the output shaft of the rotating motor is provided with a welding laser generator through a support arm.

[0016] According to a lithium-ion battery current collector welding device provided by the present invention, a sleeve is connected to the bottom of the telescopic end of the telescopic mechanism, and the rotating motor is fixedly installed in the sleeve.

[0017] According to a lithium-ion battery current collector welding device provided by the present invention, the support arm includes an upper cross bar and an oblique arm connected to one end of the upper cross bar, the other end of the upper cross bar is fixedly connected to the output shaft of the rotating motor, and the welding laser generator is connected to the bottom end of the oblique arm.

[0018] According to a lithium-ion battery current collector welding device provided by the present invention, the telescopic mechanism is any one of a hydraulic cylinder, a pneumatic cylinder or a servo telescopic mechanism.

[0019] According to a lithium ion battery current collector welding device provided by the present invention, a photoelectric switch is arranged on the upper surface of the base, and the detection end of the photoelectric switch is lower than the upper surface height of the lithium battery cell or the lithium battery composite current collector electrode.

[0020] According to a lithium-ion battery collector welding device provided by the present invention, when the light emitted by the photoelectric switch is blocked by the lithium battery cell or the lithium battery composite current collector electrode, the driving mechanism suspends operation, and the distance between adjacent lithium battery cells or lithium battery composite current collector electrodes satisfies: when the driving mechanism suspends operation, the welding laser generator corresponds to the welding position of the lithium battery cell and the lithium battery ear on the lower side or the welding position of the lithium battery composite current collector electrode and the current collector metal adapter sheet.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The lithium-ion battery current collector welding equipment provided by the present invention can load materials at one end of the conveyor belt and unload materials at the other end by setting a conveying mechanism and a battery assembly support, so that the circular welding laser welding process of the lithium battery cell current collector and the lithium battery pole ear, or the lithium battery composite current collector pole piece and the current collector metal adapter plate at multiple angles, multiple points, equal spacing or unequal spacing welding positions can be realized, and the welding process can be carried out continuously, thereby improving the processing efficiency. Under the action of the telescopic mechanism and the rotating motor, the welding laser generator can adjust the height and the rotating circular welding area, thereby realizing the multi-angle and flexible welding process design for the welding position. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a structural schematic diagram of the lithium ion battery current collector welding equipment provided by the present invention;

[0025] Figure 2 For the present invention Figure 1 Right side view;

[0026] Figure 3 It is a schematic diagram of the connection structure between the telescopic mechanism and the welding mechanism of the present invention;

[0027] Figure 4 It is a schematic structural diagram of the battery assembly support of the present invention.

[0028] Reference numerals:

[0029] 1. Base; 2. Roller; 3. Conveyor belt; 4. Driven pulley; 5. Driving motor;

[0030] 6. Mounting slot; 7. Battery assembly support; 71. L-shaped folding plate; 72. Side baffle;

[0031] 73. Battery assembly installation space; 74. Current collector support plate;

[0032] 75. Paste and fix the adhesive layer; 76. Fix and tighten the stop bar; 8. Install the frame;

[0033] 9. Telescopic mechanism; 10. Seat; 11. Rotating motor; 12. Support arm;

[0034] 13. Welding laser generator; 14. Lithium battery cell; 15. Photoelectric switch;

[0035] 16. Lithium battery composite current collector electrode. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Combine the following Figure 1-Figure 4 The invention provides a lithium-ion battery current collector welding device, which includes: a base 1 , a transmission mechanism, a driving mechanism, a battery assembly support 7 and a mounting frame 8 .

[0038] like Figure 1 and Figure 2 As shown, the base 1 is a horizontally arranged long strip and has a mounting groove 6 inside. The mounting groove 6 extends upward and passes through the upper surface of the base 1, and the lower side of the mounting groove 6 extends downward to form a storage groove; the cross-section of the mounting groove 6 is approximately a "cross" shape, and the storage groove and the space where the mounting groove 6 passes upward through the base 1 meet the occupancy of the battery assembly support 7 and the lithium battery cell 14 or the lithium battery composite current collector electrode 16.

[0039] The conveying mechanism is arranged in the mounting groove 6; the conveying mechanism includes a plurality of rollers 2 rotatably arranged in the mounting groove 6, the two ends of the rollers 2 are respectively connected to the inner walls on both sides of the mounting groove 6 through bearings, the rollers 2 are arranged equidistantly in the mounting groove 6, the rollers 2 rotate under the drive of the driving mechanism, and the outer parts of the plurality of rollers 2 are sleeved with conveyor belts 3, and the conveyor belts 3 circulate and rotate as the rollers 2 rotate.

[0040] like Figure 1 As shown, the driving mechanism is arranged on the outer wall of the base 1, and is used to drive the transmission mechanism; the driving mechanism includes a driving motor 5, a driving pulley and a driven pulley 4, the driving motor 5 is installed on the outer wall of the base 1, and the output end of the driving motor 5 is installed with a driving pulley, one end of a roller 2 thereof extends to the outside of the base 1 and is installed with a driven pulley 4, and the driving pulley and the driven pulley 4 are connected by a belt. The driving motor 5 drives the driven pulley 4 and the roller 2 to rotate through the coordinated connection of the driving pulley, the driven pulley 4 and the belt, so as to transmit the battery assembly support 7, the lithium battery cell 14 and the lithium battery pole ear on the conveyor belt 3, or transmit the battery assembly support 7, the lithium battery composite current collector pole piece 16 and the current collector metal adapter sheet on the conveyor belt 3, so as to facilitate subsequent processing.

[0041] like Figure 2 and Figure 4As shown, the battery assembly support 7 is arranged on the conveying mechanism, and is used to carry the lithium battery cell 14 and the lithium battery pole ear, or to carry the lithium battery composite current collector pole piece 16 and the current collector metal adapter plate; specifically, the battery assembly support 7 is equidistantly arranged on the conveyor belt 3, and the battery assembly support 7 includes two symmetrically arranged L-shaped folding plates 71, the L-shaped folding plates 71 are fixed on the conveyor belt 3, and side baffles 72 are arranged on both sides of the L-shaped folding plates 71. A battery assembly installation space 73 is formed between the two L-shaped folding plates 71 and the side baffles 72 arranged on the L-shaped folding plates 71. The lithium battery cell 14 or the lithium battery composite current collector pole piece 16 is installed in the battery assembly installation space 73, and an upwardly inclined current collector support plate 74 is arranged on the side baffle 72 on one side, and a bonding and fixing adhesive layer 75 for fixing the lithium battery pole ear or a fixed pressing strip 76 for fixing the current collector metal adapter plate is provided on the current collector support plate 74.

[0042] like Figure 2 As shown, the mounting frame 8 is arranged on the upper surface of the base 1, and the shape of the mounting frame 8 is n-shaped. The bottom end of the mounting frame 8 spans across the two sides of the mounting groove 6. The inner side of the mounting frame 8 is provided with a welding mechanism for welding the lithium battery cell 14 and the lithium battery pole ear or the lithium battery composite current collector pole piece 16 and the current collector metal adapter sheet through a telescopic mechanism 9. Further, as Figure 3 As shown, the welding mechanism includes a rotating motor 11 arranged at the bottom of the telescopic end of the telescopic mechanism 9, and a sleeve 10 is connected to the bottom of the telescopic end of the telescopic mechanism 9. The rotating motor 11 is fixedly installed in the sleeve 10. When installing, the rotating motor 11 is placed in the sleeve 10, and then screwed to the sleeve 10 from the side with screws, and the ends of the screws pass through the sleeve 10 and are supported on the outer wall of the rotating motor 11. The connection of the screws facilitates the installation and loosening of the rotating motor 11.

[0043] The output shaft of the rotating motor 11 is provided with a welding laser generator 13 through a support arm 12. The support arm 12 includes an upper crossbar and an oblique arm connected to one end of the upper crossbar. The other end of the upper crossbar is fixedly connected to the output shaft of the rotating motor 11. The welding laser generator 13 is connected to the bottom end of the oblique arm. The oblique arm is provided to not affect the use of the welding laser generator 13, and it is not easy to cause side obstruction to the welding laser generator 13, so that the operation space of the welding laser generator 13 is larger.

[0044] The telescopic mechanism 9 is any one of a hydraulic cylinder, a pneumatic cylinder or a servo telescopic mechanism, which is selected according to the actual use.

[0045] like Figure 1As shown, a photoelectric switch 15 is provided on the upper surface of the base 1. After the lithium battery cell 14 or the lithium battery composite current collector pole piece 16 is installed in the battery assembly installation space 73, the upper surface height of the lithium battery cell 14 or the lithium battery composite current collector pole piece 16 is higher than the upper surface height of the base 1, and the detection end of the photoelectric switch 15 is lower than the upper surface height of the lithium battery cell 14 or the lithium battery composite current collector pole piece 16. When the light emitted by the photoelectric switch 15 is blocked by the lithium battery cell 14 or the lithium battery composite current collector pole piece 16, the driving mechanism is suspended, and the distance between adjacent lithium battery cells 14 or lithium battery composite current collector pole pieces 16 satisfies: when the driving mechanism is suspended, the welding laser generator 13 corresponds to the welding position of the lithium battery cell 14 and the lithium battery pole ear on the lower side or the welding position of the lithium battery composite current collector pole piece 16 and the current collector metal adapter.

[0046] The working principle of the present invention is as follows: when in use, the lithium battery pole ear is placed against the current collector support plate 74 at one end of the conveyor belt 3 and fixed by pasting and fixing the adhesive layer 75, the corresponding welded portion of the lithium battery cell 14 and the lithium battery pole ear is placed in the battery assembly installation space 73, and the pole ear is made to correspond to its welding position, and the lithium battery pole ear is pressed on the current collector of the lithium battery cell 14; or when in use, the current collector metal adapter is placed against the current collector support plate 74 at one end of the conveyor belt 3 and fixed by pressing and fixing the fixing strip 76, the corresponding welded portion of the lithium battery composite current collector pole piece 16 and the current collector metal adapter is placed in the battery assembly installation space 73, so that the current collector metal adapter corresponds to its welding position, and the current collector metal adapter is pressed on the current collector of the lithium battery composite current collector pole piece 16;

[0047] Then, the conveyor belt 3 is driven to rotate toward the other end by the driving motor 5, and at the same time, the battery assembly support 7 and the lithium battery cell 14 or the lithium battery composite current collector electrode 16 thereon are driven to move.

[0048] The conveyor belt 3 conveys the lithium battery cell 14 and the lithium battery pole ear or the lithium battery composite current collector pole piece 16 and the current collector metal adapter plate from one end to the other end. When the light emitted by the photoelectric switch 15 is blocked by the lithium battery cell 14 or the lithium battery composite current collector pole piece 16, the photoelectric switch 15 controls the power supply circuit of the drive motor 5 to be temporarily disconnected. At this time, the lower side of the welding laser generator 13 is just parked with a lithium battery cell 14 and a lithium battery pole ear or a lithium battery composite current collector pole piece 16 and the current collector metal adapter plate. The telescopic mechanism 9 drives the welding laser generator 13 to descend, so that the welding laser generator 13 is close to the welding position of the lithium battery cell 14 and the lithium battery pole ear or the lithium battery composite current collector pole piece 16 and the current collector metal adapter plate. The welding laser generator 13 is driven to rotate by the rotating motor 11, so that the welding laser generator 13 can rotate around the first welding position for one circle. The welding laser generator 13 emits a laser to start welding. The first welding position is laser welded for one circle. After the first welding position is welded, the driving motor 5 is controlled to drive the conveyor belt 3 to rotate according to the set distance between the second welding position and the first welding position, and the battery assembly support 7 and the lithium battery cell 14 or the lithium battery composite current collector electrode 16 thereon are driven to move the set distance between the second welding position and the first welding position. The driving mechanism is suspended, and the welding laser generator 13 performs circular weld printing welding corresponding to the second welding position of the lithium battery cell 14 and the lithium battery pole ear or the lithium battery composite current collector electrode 16 and the collector metal adapter plate on the lower side. In this way, a circular weld printing laser welding process of multiple equally spaced or unequally spaced welding positions between the lithium battery cell 14 and the lithium battery pole ear or between the lithium battery composite current collector electrode 16 and the collector metal adapter plate is realized. After the welding of the last welding position is completed, the telescopic mechanism 9 and the rotating motor 11 drive the welding laser generator 13 to reset.

[0049] Afterwards, the driving motor 5 continues to supply power and drives the conveyor belt 3 to move, so that the battery assembly support 7 and the lithium battery cell 14 or the lithium battery composite current collector electrode 16 are transported until the next lithium battery cell 14 or the lithium battery composite current collector electrode 16 blocks the photoelectric switch 15. At this time, the telescopic mechanism 9 and the rotating motor 11 drive the welding laser generator 13 to weld the corresponding lithium battery cell 14 and the lithium battery ear or the lithium battery composite current collector electrode 16 and the collector metal adapter plate on the lower side. In this way, continuous welding can be performed, and the welded lithium battery cell 14 or the lithium battery composite current collector electrode 16 can be removed at the end of the conveyor belt 3.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A lithium-ion battery current collector welding device, characterized in that: include: A base, wherein a mounting groove is formed inside the base, the mounting groove extends upward and penetrates the upper surface of the base, and the lower side of the mounting groove extends downward to form a storage groove; A transmission mechanism is arranged in the installation groove; A driving mechanism, disposed on the outer side wall of the base, for driving the conveying mechanism; A battery assembly support, arranged on the conveying mechanism, for carrying lithium battery cells and lithium battery tabs, or for carrying lithium battery composite current collector pole pieces and current collector metal adapter sheets; A mounting frame is arranged on the upper surface of the base, and a welding mechanism for welding a lithium battery cell and a lithium battery pole ear or a lithium battery composite current collector pole piece and a current collector metal adapter sheet is arranged on the inner side of the mounting frame through a telescopic mechanism; The conveying mechanism comprises a plurality of rollers rotatably arranged in the mounting groove, and a conveyor belt is sleeved on the outside of the plurality of rollers; The battery assembly support includes two symmetrically arranged L-shaped folding plates, which are fixed on the conveyor belt. Side baffles are arranged on both sides of the L-shaped folding plates. A battery assembly installation space is formed between the two L-shaped folding plates and the side baffles arranged on the L-shaped folding plates. The lithium battery cell or the lithium battery composite current collector electrode is installed in the battery assembly installation space. An upwardly inclined current collector support plate is arranged on the side baffle on one side, and a bonding and fixing adhesive layer for fixing the lithium battery electrode ear or a fixed compression strip for fixing the current collector metal adapter is arranged on the current collector support plate.

2. The lithium-ion battery current collector welding equipment according to claim 1, characterized in that: The driving mechanism includes a driving motor, a driving pulley and a driven pulley. The driving motor is installed on the outer side wall of the base. The output end of the driving motor is installed with the driving pulley. One end of the roller extends to the outside of the base and is installed with the driven pulley. The driving pulley and the driven pulley are connected by a belt.

3. The lithium-ion battery current collector welding equipment according to claim 1, characterized in that: The welding mechanism comprises a rotating motor arranged at the bottom of the telescopic end of the telescopic mechanism, and the output shaft of the rotating motor is provided with a welding laser generator through a supporting arm.

4. The lithium-ion battery current collector welding equipment according to claim 3, characterized in that: The bottom of the telescopic end of the telescopic mechanism is connected with a sleeve seat, and the rotating motor is fixedly installed in the sleeve seat.

5. The lithium-ion battery current collector welding equipment according to claim 3, characterized in that: The support arm comprises an upper cross bar and an oblique arm connected to one end of the upper cross bar, the other end of the upper cross bar is fixedly connected to the output shaft of the rotating motor, and the welding laser generator is connected to the bottom end of the oblique arm.

6. The lithium-ion battery current collector welding equipment according to claim 1, characterized in that: The telescopic mechanism is any one of a hydraulic cylinder, a pneumatic cylinder or a servo telescopic mechanism.

7. The lithium-ion battery current collector welding equipment according to claim 3, characterized in that: A photoelectric switch is arranged on the upper surface of the base, and a detection end of the photoelectric switch is lower than the upper surface height of the lithium battery cell or the lithium battery composite current collector electrode.

8. The lithium-ion battery current collector welding equipment according to claim 7, characterized in that: When the light emitted by the photoelectric switch is blocked by the lithium battery cell or the lithium battery composite current collector electrode, the driving mechanism suspends operation, and the distance between adjacent lithium battery cells or lithium battery composite current collector electrodes satisfies: when the driving mechanism suspends operation, the welding laser generator corresponds to the welding position of the lithium battery cell and the lithium battery ear on the lower side or the welding position of the lithium battery composite current collector electrode and the current collector metal adapter plate.

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