A welding fixture

Abstract

The present invention discloses a welding fixture, which belongs to the technical field of welding devices. The welding fixture is used to press the pole lugs and nickel sheets of a battery module onto the busbar of the battery module for welding, and includes: a receiving cavity, the receiving cavity is used to receive and fix the battery module; a cover plate, the cover plate is arranged at the upper end of the receiving cavity in a liftable manner; and a pressing block, the pressing block is fixed on the busbar and is located on the lower side of the cover plate, the pressing block is arranged opposite to the pole lugs and the nickel sheet, and when the cover plate descends and presses on the upper end of the receiving cavity, the pressing block abuts against the pole lugs and the nickel sheet at the same time and is pressed onto the busbar. The welding fixture has the following beneficial effects: the structure of the welding fixture is relatively simple, and the pole lugs and the nickel sheet can be pressed onto the busbar at the same time, which saves time and effort, has high working efficiency, and has good pressing effect.

Description

Technical Field

[0001] The invention relates to the technical field of welding devices, and in particular to a welding fixture. Background Art

[0002] New energy vehicles have become the overall trend of the development of the automotive industry. Most new energy vehicles are pure electric vehicles or hybrid vehicles that use lithium batteries as electrical energy storage devices. Due to the characteristics of lithium batteries themselves, hard-shell batteries with steel shells, aluminum shells and plastic shells generally have safety hazards of explosion. Soft-pack batteries have gradually replaced hard-shell batteries due to their advantages such as high safety, high energy density and long life.

[0003] In the manufacturing process of soft-pack battery modules, laser welding is required to achieve high-voltage electrical connection inside the soft-pack battery module. In order to ensure the effect of laser welding, the tabs and nickel sheets of the battery cells of the soft-pack battery module need to be pressed tightly with a welding fixture before welding, so that they are in close contact with the busbar, and then welding can be carried out.

[0004] However, the existing welding fixture of the soft-pack battery module has a complex structure, and when the pole ear and the nickel sheet are pressed, the pole ear and the nickel sheet cannot be pressed at the same time because the thickness of the nickel sheet is inconsistent with the thickness of the pole ear. They can only be pressed separately, which is time-consuming and labor-intensive, resulting in low work efficiency and high production cost; and the pressing degree of the pole ear and the nickel sheet is not easy to control, resulting in poor fit with the bus, resulting in poor welding effect and easy welding failure; when the specifications of the battery module are different, it is necessary to replace the matching welding fixture, which is not compatible with battery modules of various specifications, making the versatility of the welding fixture low.

[0005] In view of the above problems, a welding fixture is urgently needed to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide a welding fixture, which has a simple structure and can simultaneously press the tab and the nickel sheet as a whole, has high working efficiency, and has a good pressing effect.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] A welding fixture, used for pressing a tab and a nickel sheet of a battery module onto a busbar of the battery module for welding, comprising:

[0009] An accommodating cavity, the accommodating cavity is used to accommodate and fix the battery module;

[0010] a cover plate, the cover plate being liftably disposed at the upper end of the accommodating cavity; and

[0011] A pressing block is fixed on the bus and is located at the lower side of the cover plate. The pressing block is arranged opposite to the pole ear and the nickel sheet. When the cover plate descends and presses on the upper end of the accommodating cavity, the pressing block abuts against the pole ear and the nickel sheet at the same time and is pressed against the bus.

[0012] Preferably, a first height of the pressing block after it abuts against the tab and a second height of the pressing block after it abuts against the nickel sheet are the same.

[0013] Preferably, the pressing block is fixed to the busbar by a fastener, and a spring is provided on the fastener. The tightness of the fastener is adjusted to make the spring generate elastic force so that the tab and the nickel sheet fit more closely to the busbar.

[0014] Preferably, the pressing block is provided with a first through hole matched with the pole tab, and the pole tab is welded to the busbar through the first through hole.

[0015] Preferably, the pressing block is further provided with a second through hole matched with the nickel sheet, and the nickel sheet is welded to the busbar through the second through hole.

[0016] Preferably, both the first through hole and the second through hole are provided with an oblique angle, and the oblique angle is used to avoid the direction of the laser beam.

[0017] Preferably, first baffles are provided on both sides of the accommodating cavity, and driving members are provided on the two first baffles, and the driving members are configured to drive the cover plate to move in a vertical direction so that the battery module is placed in the accommodating cavity.

[0018] Preferably, the driving member includes a movable portion and a fixed portion, the fixed portion is arranged on the first side plate, the movable portion is arranged on the cover plate, and the movable portion can move in a vertical direction relative to the fixed portion.

[0019] Preferably, the welding fixture further comprises a bottom plate, which is located at the bottom of the accommodating cavity and connected to a workbench of the welding machine. A roller is arranged on the bottom plate, and the battery module can slide on the roller.

[0020] Preferably, the welding fixture further comprises a push plate, the bottom end of the push plate abuts against the roller, the top end of the push plate abuts against the bottom end of the battery module, and the push plate can slide along the roller to the welding station with the battery module.

[0021] The beneficial effects of the present invention are as follows: when the cover plate descends and is pressed on the upper end of the accommodating cavity, the cover plate abuts against the pressing block downward, so that the pressing block can abut against the pole ear and the nickel sheet at the same time and be pressed against the bus. The structure of the welding fixture is relatively simple, and the pole ear and the nickel sheet can be pressed against the bus at the same time, which saves time and effort, has high work efficiency and low production cost; the pressing degree of the pole ear and the nickel sheet can be uniformly controlled, so that the contact tightness with the bus is good, so that the welding effect is better and there will be no welding failure; and when the specifications of the battery module are different, there is no need to replace the matching welding fixture every time, only the size of the accommodating cavity and the pressing block needs to be adjusted, and the welding fixture has high versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 An assembly diagram of the welding fixture provided by the present invention;

[0023] Figure 2 An exploded schematic diagram of the welding fixture provided by the present invention;

[0024] Figure 3 A schematic diagram of a partially exploded structure of the top end of the welding fixture provided by the present invention (excluding the cover plate);

[0025] Figure 4 for Figure 3 A local enlarged schematic diagram of point A in the middle.

[0026] Description of reference numerals:

[0027] In the figure:

[0028] 1-cover plate; 11-third through hole;

[0029] 2-driving member; 21-movable part; 22-fixed part;

[0030] 3-second baffle; 4-first baffle; 5-push plate; 6-roller; 7-bottom plate;

[0031] 8-battery module; 81-ear; 82-nickel sheet; 83-bus;

[0032] 9-pressing block; 91-first through hole; 92-second through hole;

[0033] 10- Spring; 11- Fastener. DETAILED DESCRIPTION

[0034] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0035] Any feature disclosed in this specification, unless otherwise stated, may be replaced by other equivalent or alternative features having similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features. Throughout the specification, the same reference numerals indicate the same elements.

[0036] In order to make the technical problem solved by the present invention, the technical solution adopted and the technical effect achieved more clearly, the technical solution of the present invention is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0037] In this embodiment, a welding fixture is proposed. The welding fixture is arranged on a welding machine workbench (not shown in the figure), and is used to press the pole ear 81 and the nickel sheet 82 of the battery module 8 onto the bus 83 of the battery module 8 for welding. The pole ear 81 and the nickel sheet 82 are both located on the bus 83 on the top surface of the battery module 8, and the welding fixture is used to press the pole ear 81 and the nickel sheet 82 onto the bus 83 at the same time, and then weld them onto the bus 83.

[0038] In this embodiment, laser welding is used to weld the tab 81 and the nickel sheet 82 to the bus 83. Laser welding does not require the use of electrodes, and there is no concern about electrode contamination or damage. Moreover, since it is not a contact welding process, the wear and deformation of the machine tools can be minimized. The laser beam is easy to focus, align and be guided by optical instruments. It can be placed at an appropriate distance from the workpiece and can be guided between the machines or obstacles around the workpiece. Other welding methods cannot be used due to the above-mentioned space limitations. The laser beam can be focused on a very small area, and small and closely spaced components can be welded.

[0039] like Figure 1 and Figure 2 As shown, the welding fixture includes a accommodating cavity, a cover plate 1 and a pressing block 9. The accommodating cavity is used to accommodate the battery module 8 and fix the battery module 8 in the accommodating cavity; the cover plate 1 is located at the upper end of the accommodating cavity and can be raised and lowered at the upper end of the accommodating cavity; when the cover plate 1 is moved vertically upward to provide a larger accommodating space, the battery module 8 can be conveniently placed in the accommodating cavity intact.

[0040] Among them, the pressing block 9 is fixed on the bus 83 and is located on the lower side of the cover plate 1. The pressing block 9 is arranged opposite to the pole ear 81 and the nickel sheet 82, and the pole ear 81 and the nickel sheet 82 are located between the pressing block 9 and the bus 83. When the cover plate 1 is lowered and pressed on the upper end of the accommodating cavity, the pressing block 9 can simultaneously abut against the pole ear 81 and the nickel sheet 82 and be pressed on the bus 83; at the same time, in the process of fixing the pressing block 9 to the bus 83, the pole ear 81 and the nickel sheet 82 can be further pressed downward. In this embodiment, the battery module 8 is a soft-pack battery module. The soft-pack battery module has the characteristics of high safety, high energy density and long life.

[0041] Furthermore, when the pressing block 9 abuts against the pole ear 81, a first height is formed together with the pole ear 81; when the pressing block 9 abuts against the nickel sheet 82, a second height is formed together with the nickel sheet 82, that is, the first height and the second height are the same, so that the pressing block 9 can abut against the pole ear 81 and the nickel sheet 82 at the same time.

[0042] By raising the cover plate 1, the battery module 8 is placed and fixed in the accommodating cavity, and then the cover plate 1 is lowered to abut against the pressing block 9, so that the pressing block 9 is tightly abutted against the pole ear 81 and the nickel sheet 82 at the same time, so that the pole ear 81 and the nickel sheet 82 are tightly fitted with the bus 83 at the same time; and in the process of fixing the pressing block 9 to the bus 83, the pole ear 81 and the nickel sheet 8 can be further pressed downward to make the pole ear 81 and the nickel sheet 82 fit more tightly with the bus 83 at the same time. The structure of the welding fixture is relatively simple, and the pole ear 81 and the nickel sheet 82 can be pressed onto the bus 83 at the same time, saving time and labor, making the work efficiency of pressing and subsequent welding higher, and the production cost lower; the pressing degree of the pole ear 81 and the nickel sheet 82 can be uniformly controlled, so that the fitting degree with the bus 83 is better, so that the welding effect is better and there will be no welding failure.

[0043] In this embodiment, when the size specifications of the battery module 8 that needs to be pressed and welded change, it is only necessary to adjust the length, width and height parameters of the welding fixture and the position of the pressing block 9. The welding fixture can be used for pressing and welding, and there is no need to replace the matching welding fixture, which makes the welding fixture more versatile.

[0044] Furthermore, if Figure 2 As shown, the pressing block 9 is fixed on the busbar 83 by a fastener 11, and a spring 10 is provided on the fastener 11. The tightening degree of the fastener 11 is adjusted to make the spring 10 generate elastic force. The elastic force generated can make the pressing block 9 more closely abut against the pole ear 81 and the nickel sheet 82, and make the pole ear 81 and the nickel sheet 82 fit more closely with the busbar 83, so that the busbar area is reliable. And it can facilitate subsequent welding, so that the welding can achieve a reliable effect. In this embodiment, the fastener 11 is a bolt. In other embodiments, the fastener 11 can also be a stud.

[0045] Specifically, Figure 3 and Figure 4As shown, the pressing block 9 is provided with a first through hole 91 adapted to the pole ear 81, and the first through hole 91 provides an operating space for welding, and the pole ear 81 can be welded to the bus 83 through the first through hole 91. The pressing block 9 is also provided with a second through hole 92 adapted to the nickel sheet 82, and the second through hole 92 provides an operating space for welding, and the nickel sheet 82 is welded to the bus 83 through the second through hole 92. Among them, the first through hole 91 and the second through hole 92 are both provided with an oblique angle, which can effectively avoid the direction of the laser beam, so that the laser beam can hit the welding points of the pole ear 81 and the nickel sheet 82 and the bus 83 respectively, and will not hit the pressing block 9, causing welding failure. In this embodiment, the pressing block 9 is a copper plate. The copper plate has good corrosion resistance, and its performance is stable in dry air, and it can better protect the pole ear 81 and the nickel sheet 82.

[0046] Since the cover plate 1 is located on the upper side of the pressing block 9, in order to be able to weld the pole ear 81 through the first through hole 91 and weld the nickel sheet 82 through the second through hole 92, a third through hole 11 that is compatible with both the first through hole 91 and the second through hole 92 is provided on the cover plate 1, so that the welding equipment can pass through the third through hole 11 and smoothly enter the first through hole 91 and the second through hole 92 for welding.

[0047] Furthermore, if Figure 2 As shown, a first baffle 4 is provided on both sides of the accommodating cavity, and a driving member 2 is provided on the first baffle 4. The driving member 2 is configured to drive the cover plate 1 to move in the vertical direction so that the battery module 8 can be placed in the accommodating cavity. The driving member 2 includes a movable portion 21 and a fixed portion 22. The fixed portion 22 is provided on the first side plate, and the movable portion 21 is provided on the cover plate 1. The movable portion 21 and the cover plate 1 can move in the vertical direction relative to the fixed portion 22. In this embodiment, the cover plate 1 is a nylon cover plate. The nylon cover plate is light in weight, which can facilitate the movable portion 21 to move together with the nylon cover plate in the vertical direction relatively easily; and the nylon cover plate has good corrosion resistance, which can better protect the pressing block 9, the pole ear 81 and the nickel sheet 82 located on the lower side of the nylon cover plate.

[0048] When the driving member 2 is working, its movable part 21 can move upward in the vertical direction relative to the fixed part 22 to the maximum stroke of the driving member 2, so as to provide a larger accommodation space, and the battery module 8 can be pushed into the accommodation cavity intact; wherein, in order to smoothly push the battery module 8 into the accommodation cavity, the clearance between the two first baffles 4 and the battery module 8 is 0.25mm; and then the movable part 21 is moved downward in the vertical direction relative to the fixed part 22, so that the cover plate 1 abuts against the pressing block 9, so as to fix the battery module 8 in the accommodation cavity, and facilitate the pressing work. In this embodiment, the driving member 2 is a movable cylinder.

[0049] The welding fixture further includes a second baffle plate 3, which is located at the rear side of the accommodating cavity to abut against the battery module 8 to prevent the battery module 8 from falling out from the rear side during the process of pushing the battery module 8 into the accommodating cavity or subsequent pressing. In this embodiment, the first baffle plate 4 and the second baffle plate 3 are both aluminum baffle plates. Aluminum baffle plates have excellent waterproof, anti-fouling and anti-corrosion properties, high performance-price ratio, easy maintenance and long service life.

[0050] Specifically, the welding fixture also includes a base plate 7 and a push plate 5. The base plate 7 is located at the bottom of the accommodating cavity and is connected to the welding machine workbench. A roller 6 is provided on the base plate 7, and the battery module 8 can slide on the roller 6. The push plate 5 is located on the upper side of the base plate 7. The top of the push plate 5 abuts against the bottom end of the battery module 8. The bottom end of the push plate 5 contacts the roller 6, and the push plate 5 is pushed. The push plate 5 can slide on the roller 6 with the battery module 8 to the welding station. In this embodiment, the base plate 7 is a bakelite base plate made of phenolic resin. The bakelite base plate has good rigidity and can provide a relatively stable support for the battery module 8 placed on its upper side; the bakelite base plate has good chemical corrosion resistance and heat resistance, and is inexpensive.

[0051] By manually pushing the push plate 5 lightly, the push plate 5 can slide on the roller 6 with the compacted battery module 8, so that it can reach the lower side of the laser head at the welding station at a faster speed, and the pole ear 81 and the nickel sheet 82 are welded to the bus bar 83 by the laser head at the welding station. And when the welding is completed, it is easy to unload the battery module 8 from the welding fixture. Rapid welding and unloading of the battery module 8 is achieved, which greatly improves the welding and unloading efficiency and reduces the production cost.

[0052] In this embodiment, the base plate 7 is fixedly connected to the first baffle plate 4 and the second baffle plate 3 by bolts. The parameters of the vertical movement between the cover plate 1 and the first baffle plate 4 can be determined by the type of the driving member 2. When the welding fixture is fixed on the welding machine workbench, the coordinate coefficients of the three axes XYZ between the cover plate 1 and the welding machine workbench are all fixed values. When welding, it is only necessary to adjust the parameters of the welding machine and the welding procedure to perform welding on the welding fixture, which greatly improves the welding efficiency.

[0053] Among them, since all the tabs 81 and nickel sheets 82 in the battery module 8 use the same welding fixture and the same welding process, the welding effect of the entire battery module 8 tends to be consistent, making the total internal resistance of the battery module 8 relatively stable.

[0054] The specific working process of the welding fixture in the present invention is as follows: first, the cover plate 1 is driven to move upward by the movable part 21 of the driving member 2, and the battery module 8 is placed in the accommodating cavity, and then the cover plate 1 is driven to move downward by the movable part 21 of the driving member 2. Due to the driving action of the driving member 2, the cover plate 1 has a downward pressing force, and the cover plate 1 can press the pressing block 9 downward to make the pole ear 81 and the nickel sheet 82 fit tightly with the bus 83.

[0055] Then the fastener 11 is fixed on the pressing block 9 to fix the pressing block 9 on the busbar 83. During the fixing process, the pressing block 9 can be fixed on the busbar 83 more stably, so that the tab 81 and the nickel sheet 82 are more closely fitted to the busbar 83. At the same time, a spring 10 is provided on the fastener 11. During the fixing process, the spring 10 generates elastic force to make the tab 81 and the nickel sheet 82 fit more closely to the busbar 83.

[0056] Finally, by manually pushing the push plate 5, the push plate 5 drives the battery module 8 to slide on the roller 6 to the welding station. At the welding station, the laser beam first passes through the third through hole 11, and then passes through the first through hole 91 and the second through hole 92 to weld the pole ear 81 and the nickel sheet 82 to the bus 83 respectively, to complete the entire working process.

[0057] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. A welding fixture, used for pressing a tab (81) and a nickel sheet (82) of a battery module (8) onto a busbar (83) of the battery module (8) for welding, characterized in that: include: A receiving cavity, the receiving cavity being used to receive and fix the battery module (8); A cover plate (1), the cover plate (1) being arranged at the upper end of the accommodating cavity in a liftable manner; and A pressing block (9), the pressing block (9) being fixed on the busbar (83) and being located on the lower side of the cover plate (1), the pressing block (9) being arranged opposite to the pole ear (81) and the nickel sheet (82), and when the cover plate (1) descends and covers the upper end of the accommodating cavity, the pressing block (9) simultaneously abuts against the pole ear (81) and the nickel sheet (82) and is pressed against the busbar (83); A first height of the pressing block (9) after it abuts against the tab (81) and a second height of the pressing block (9) after it abuts against the nickel sheet (82) are the same; The pressing block (9) is fixed to the busbar (83) via a fastener (11); a spring (10) is provided on the fastener (11); the tightening degree of the fastener (11) is adjusted so that the spring (10) generates elastic force, so that the tab (81) and the nickel sheet (82) are more closely fitted to the busbar (83); The pressing block (9) is provided with a first through hole (91) adapted to the pole lug (81), and the pole lug (81) is welded to the busbar (83) through the first through hole (91); The pressing block (9) is also provided with a second through hole (92) adapted to the nickel sheet (82), and the nickel sheet (82) is welded to the busbar (83) through the second through hole (92); The first through hole (91) and the second through hole (92) are both provided with an oblique angle, and the oblique angle is used to avoid the direction of the laser beam.

2. The welding fixture according to claim 1, characterized in that: First baffles (4) are provided on both side surfaces of the accommodating cavity, and driving members (2) are provided on the two first baffles (4), wherein the driving members (2) are configured to drive the cover plate (1) to move in a vertical direction so as to place the battery module (8) into the accommodating cavity.

3. The welding fixture according to claim 2, characterized in that: The driving member (2) comprises a movable portion (21) and a fixed portion (22), wherein the fixed portion (22) is arranged on the first side plate, and the movable portion (21) is arranged on the cover plate (1), and the movable portion (21) is movable in a vertical direction relative to the fixed portion (22).

4. The welding fixture according to claim 1, characterized in that: The welding fixture further comprises a bottom plate (7), the bottom plate (7) being located at the bottom of the accommodating cavity and connected to a welding machine workbench, a roller (6) being arranged on the bottom plate (7), and the battery module (8) being able to slide on the roller (6).

5. The welding fixture according to claim 4, characterized in that: The welding fixture further comprises a push plate (5), the bottom end of the push plate (5) abuts against the roller (6), the top end of the push plate (5) abuts against the bottom end of the battery module (8), and the push plate (5) can slide along the roller (6) to the welding station with the battery module (8).

Images