Battery welding system and control method thereof

Abstract

The embodiment of the invention provides a battery welding system and a control method thereof.The battery welding system comprises a welding module, the welding module comprises welding equipment, a driving assembly, a vision measurement assembly and a plurality of range finders, at least part of the range finders are in driving connection with the driving end of the driving assembly, and the driving assembly drives the range finders to move in the first direction; and the vision measurement assembly is used for shooting an image of an area to be welded. According to the battery welding system disclosed by the embodiment of the invention, the distance measuring instruments are driven to move through the driving assembly, so that the distance between the distance measuring instruments in the first direction can be changed, and the distance between the distance measuring instruments corresponds to the distance between the to-be-welded areas on the battery under the condition that the distance measuring instruments are not disassembled and assembled; therefore, the efficiency of adjusting the distance between the range finders is improved, the time is saved, and the workload is reduced.

Description

[0001] This application is a divisional application of a patent application for an invention named "Battery Welding System and Its Control Method" with an application date of October 8, 2023, an application number of 202311289834.4. Technical Field

[0002] The present invention relates to the field of welding technology, and particularly to a battery welding system and its control method. Background Art

[0003] During the process of battery production and manufacturing, it is necessary to weld the pole columns of multiple battery cells together with a bus bar component to form a battery module.

[0004] Since the sizes of different types of battery cells are different, the sizes of the corresponding bus bar components are also different. Therefore, after the type of battery produced on the battery production line is changed, the spacing between the pole columns of multiple battery cells also changes accordingly, and the corresponding welding parameters also need to be changed and adjusted accordingly, which has an adverse impact on production efficiency. Summary of the Invention

[0005] In view of this, embodiments of the present invention are expected to provide a battery welding system and its control method that can improve the compatibility of welding operations for different batteries.

[0006] To achieve the above object, the technical solution of the embodiments of the present invention is realized as follows:

[0007] The embodiments of the present invention provide a battery welding system for welding the pole columns of different battery cells in a battery through a bus bar. The battery welding system includes:

[0008] A welding module, the welding module includes a welding device, a driving component, a visual measurement component, and a plurality of rangefinders. The welding device is used to weld the bus bar and the pole column. At least part of the rangefinders is drivingly connected to the driving end of the driving component. The driving component drives the rangefinders to move along a first direction, so that the spacing between the rangefinders along the first direction changes. The first direction is the arrangement direction of the battery cells connected by the bus bar. The visual measurement component is used to capture an image of the area to be welded.

[0009] In the battery welding system of the embodiments of the present invention, by driving the rangefinders to move through the driving component, the spacing between the rangefinders along the first direction can be changed, so that without disassembling the rangefinders, the spacing between the rangefinders along the first direction can correspond to the spacing between the areas to be welded on the battery along the first direction, thereby improving the efficiency of adjusting the spacing between the rangefinders, saving time, reducing the workload, and being beneficial to improving production efficiency.

[0010] In some embodiments, the welding module includes a housing with an installation cavity therein. The welding device is disposed in the installation cavity. One side of the installation cavity is open to form an avoidance opening through which the welding device can pass for welding. On the one hand, the housing provides an installation position for the welding device. On the other hand, the housing can play a certain protective role for the welding device, reducing the probability of damage caused by the welding device being collided, and the avoidance opening provides an operation passage for the welding device to pass through the housing for welding operations.

[0011] In some embodiments, the rangefinder is disposed on the outer surface of the housing and at the edge of the avoidance opening; and / or, the vision measurement component is disposed in the installation cavity. In this way, it is beneficial for the rangefinder to be as close as possible to the area to be welded, which is conducive to improving the measurement accuracy of the rangefinder. The rangefinder is located outside the housing, facilitating the debugging operation of the rangefinder and the driving component; the housing directly protects the vision measurement component without the need for additional components to protect the vision measurement component.

[0012] In some embodiments, the welding device is a laser welding device, and the welding module includes a blowing component with an air outlet for blowing out air flow. The blowing component is disposed on the emission side of the lens of the laser welding device, and the air outlet faces the laser scanning range of the laser welding device, so that the air flow blown out from the air outlet is located between the lens and the area to be welded of the battery. In this way, the air flow blown out from the air outlet can form an air curtain between the lens and the area to be welded and pass through the laser scanning range of the laser welding device. The laser can pass through the air curtain and continue to perform welding. At the same time, the high-temperature foreign matters splashed during the welding process can be blown away by the air flow and are difficult to pass through the air curtain to contact the lens, thus playing a protective role for the lens and extending the service life of the lens.

[0013] In some embodiments, the air outlet direction of the air outlet is perpendicular to the optical axis of the lens of the laser welding device. On the one hand, it reduces the probability of the air flow directly blowing on the area to be welded and the probability of foreign matters entering the area to be welded due to the blowing of the air flow, which is conducive to improving the welding quality; on the other hand, it reduces the probability of the air flow directly blowing on the lens and the probability of the air flow carrying the splashed high-temperature foreign matters directly contacting the lens, reducing the probability of the lens being damaged.

[0014] In some embodiments, the number of the blowing components is multiple, and the multiple blowing components are arranged along the extension direction of the optical axis of the lens of the laser welding device. In this way, multiple air curtains are formed between the lens and the area to be welded, further reducing the probability of the high-temperature foreign matters splashed during the welding process contacting the lens and playing a protective role for the lens.

[0015] In some embodiments, the rangefinder is a laser rangefinder, and the moving direction of the rangefinder is perpendicular to the optical axis of the lens of the laser welding device. In this way, during the movement of the rangefinder, the change in the distance relative to the area to be welded along the extension direction of the optical axis of the lens is minimized, which is conducive to reducing the measurement error caused by the change in the position of the rangefinder and improving the measurement accuracy.

[0016] In some embodiments, the direction of the ranging laser beam emitted by the rangefinder is parallel to the optical axis of the lens of the laser welding device. So that after the rangefinder completes the measurement of the distance to the area to be welded, the welding device can move a preset position compensation distance between the rangefinder and the lens of the laser welding device perpendicular to the optical axis of the lens of the laser welding device, and then welding can be carried out, which is conducive to reducing the calculation of the distance compensation amount;

[0017] And / or, the light-emitting areas of the rangefinders are flush with each other. In this way, it is conducive to reducing the difference between the position compensation distances corresponding to different rangefinders, thereby reducing the calculation amount and improving the reaction speed.

[0018] In some embodiments, the welding module includes a first protection component, and the first protection component includes a first baffle and a first driving member. The driving end of the first driving member is drivingly connected to the first baffle so that the first baffle can selectively cover the light-emitting area of the rangefinder. In this way, during the welding process of the welding device, the first baffle can protect the light-emitting area of the rangefinder, reducing the probability that high-temperature foreign objects splashing during welding adhere to the light-emitting area of the rangefinder, thereby reducing the probability of damage to the rangefinder.

[0019] In some embodiments, the vision measurement component and the rangefinder are arranged at intervals, the welding device is located between the vision measurement component and the rangefinder, and the air blowing component is located on one side of the welding device perpendicular to the relative direction of the vision measurement component and the rangefinder, and the air outlet is lower than the vision measurement component and the rangefinder. On the one hand, it is conducive to making the structure of the battery welding system more compact and improving the space utilization rate; on the other hand, the airflow blown out by the air outlet can also partially flow through the surfaces of the vision measurement component and the rangefinder, which is conducive to reducing the probability that foreign objects during welding contaminate the light-emitting area of the rangefinder and the shooting end of the vision measurement component, and is conducive to enabling both the rangefinder and the vision measurement component to work during welding.

[0020] In some embodiments, the driving assembly includes a driving motor, a lead screw, a guide rail and a slider. The driving end of the driving motor is drivingly connected to one end of the lead screw. The slider is slidably engaged with the guide rail. The guide rail is in the same extending direction as the lead screw. At least one distance measuring instrument is disposed on the slider. In this way, by driving the lead screw to rotate by the driving motor and the screw-thread fit between the lead screw and the slider, the movement of the distance measuring instrument located on the slider is realized, and further the purpose of changing the distance between the distance measuring instruments is achieved.

[0021] In some embodiments, the battery welding system includes a robot, and the execution end of the six-axis robot is connected to the welding module. By using a robot, the welding module can flexibly move in space along various trajectories and at various angles, which is convenient for the welding module to avoid other surrounding objects during movement. At the same time, it is beneficial for the welding module to weld the area to be welded from a suitable angle, thereby improving the welding quality.

[0022] In some embodiments, the battery welding system further includes:

[0023] A conveying module for conveying the battery to be welded to the welding operation position;

[0024] A positioning module for fixing the positions of the battery cells and the positions of the tab pieces after the battery reaches the welding operation position;

[0025] A pressing plate module for pressing on the tab piece after the positions of the battery cell and the tab piece are fixed, so that the tab piece is attached to the pole column.

[0026] In this way, through the cooperation among the conveying module, the positioning module, the pressing plate module and the welding module, the battery can be successfully welded and the welding quality can be improved.

[0027] The embodiment of the present invention further provides a control method for a battery welding system. The control method includes:

[0028] Controlling the robot to drive the welding module to move to the ranging position;

[0029] Obtaining the distance between the areas to be welded of adjacent battery cells in the battery, and controlling the driving assembly to drive the distance measuring instruments to move so that the distance between the distance measuring instruments corresponds to and is equal to the distance between the areas to be welded of the battery cells;

[0030] Controlling each of the distance measuring instruments to respectively measure the ranging values between it and the corresponding areas to be welded of the battery cells;

[0031] Calculating the defocus compensation distance for welding the areas to be welded of the battery cells according to the focal length of the laser welding equipment and the ranging values;

[0032] According to each of the defocus compensation distances, control the robot to drive the welding module to move to the welding position corresponding to the to-be-welded area of each battery cell for welding;

[0033] Control the laser welding equipment to perform welding.

[0034] Through the above control method, the battery welding system can adaptively adjust the positions of the respective rangefinders for different types of batteries to obtain the actual distance between the laser welding equipment and the to-be-welded area on the battery. Taking this as a reference, it is convenient to move the laser welding equipment to achieve the purpose that the focus of the laser welding equipment is near the to-be-welded area, thereby being beneficial to improving the welding quality.

[0035] In some embodiments, before controlling the laser welding equipment to perform welding, the control method further includes:

[0036] Control the air blowing assembly to be turned on so as to form an air curtain between the lens of the laser welding equipment and the battery.

[0037] In this way, the probability that the flying high-temperature foreign matters come into contact with the lens during the welding operation of the laser welding equipment and cause damage to the lens is reduced. Description of the Drawings

[0038] Figure 1 Schematic diagram of a battery welding device in an embodiment of the present invention;

[0039] Figure 2 Schematic diagram of the welding module in a first perspective in an embodiment of the present invention;

[0040] Figure 3 For Figure 2 Schematic diagram of the welding module in a second perspective in

[0041] Figure 4 Schematic diagram of the air blowing assembly in an embodiment of the present invention;

[0042] Figure 5 Schematic diagram of the driving assembly in an embodiment of the present invention;

[0043] Figure 6 Schematic diagram of a battery cell and a tab in an embodiment of the present invention;

[0044] Figure 7 Schematic diagram of the flow of the control method of the battery welding device in an embodiment of the present invention.

[0045] Description of the Reference Numerals

[0046] Welding module 10; welding equipment 11; laser scanning range 11a; lens optical axis 11b; lens 111; drive assembly 121; drive motor 1211; lead screw 1212; guide rail 1213; slider 1214; rangefinder 122; light-emitting area 1221; housing 13; installation cavity 13a; avoidance opening 13b; air-blowing assembly 14; air outlet 14a; first protection assembly 15; first baffle 151; first driving member 152; protective case 16; visual measurement assembly 17; second protection assembly 18; second baffle 181; second driving member 182; robot 20; execution end 21; battery cell 30; area to be welded 30a; pole 31; tab 40. Detailed implementation manner

[0047] It should be noted that, without conflict, the embodiments in the present invention and the technical features in the embodiments can be combined with each other. The detailed description in the specific implementation manner should be understood as an explanatory illustration of the gist of the present invention and should not be regarded as an improper limitation to the present invention.

[0048] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" and any variations thereof in the description of the specification and the above-mentioned drawings of the present invention are intended to cover non-exclusive inclusion.

[0049] In the description of the embodiments of the present invention, the technical terms "first", "second", "third", etc. are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of the present invention, the meaning of "a plurality" is more than two, unless otherwise specifically and clearly defined.

[0050] Referring to "embodiment" herein means that the specific features, structures or characteristics described in combination with the embodiment can be included in at least one embodiment of the present invention. The phrase appears in various positions in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0051] In the description of the embodiments of the present invention, the term "and / or" is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after.

[0052] In the description of the embodiments of the present invention, the technical terms "vertical direction", "upper", "lower" or positional relationship are based on the attached Figure 2 The orientation or position relationship shown in the technical term "first direction" is based on the attached Figure 6 The orientation or positional relationship shown is only for the convenience of describing the embodiments of the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed, operated or used in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present invention.

[0053] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0054] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the technical term "contact" should be understood in a broad sense, and can be direct contact or contact through an intermediate medium layer. It can be contact with essentially no interaction force between the two contacting parties, or it can be contact with interaction force between the two contacting parties.

[0055] The following is a detailed description of the embodiments of the present invention.

[0056] At present, batteries are increasingly used in life and industry. Batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but are also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, and aerospace and other fields. With the continuous expansion of battery application areas, the market demand is also constantly expanding.

[0057] In the process of producing batteries, welding equipment is needed to weld the poles of two adjacent battery cells in the battery through the current collector, so as to realize the series and parallel electrical connection of each battery cell in the battery. Before welding, the distance between the welding equipment and the area to be welded needs to be measured by a distance meter to obtain a reference for automatic welding. Since there are multiple battery cells in the battery, multiple distance meters are needed to measure the distance between the corresponding areas to be welded on multiple battery cells and the welding equipment in turn.

[0058] Among different types of batteries, due to the differences in the specifications and dimensions of the internal battery cells, the distances between the adjacent two battery cell poles that the busbar components need to connect are different. Therefore, the sizes of the busbar components for electrically connecting the poles of the adjacent two battery cells are also different.

[0059] In the prior art, during the production process of switching different types of batteries on the production line, in order to adapt to the changes in the distances between the poles of the adjacent two battery cells and the size changes of the busbar components after switching, and since the measurement coverage range of the rangefinder is limited, it is necessary to manually disassemble and reinstall multiple rangefinders. Thus, the production cost is increased, which has an adverse impact on the production efficiency.

[0060] An embodiment of the present invention provides a battery welding system for welding between the poles 31 of different battery cells 30 in a battery through a busbar 40. Refer to Figures 1 to 3 , the battery welding system includes a welding module 10. The welding module 10 includes a welding device 11, a driving component 121, and multiple rangefinders 122. The welding device 11 is used to weld the busbar 40 and the pole 31. At least some of the rangefinders 122 are drivingly connected to the driving end of the driving component 121. The driving component 121 drives the rangefinders 122 to move in a first direction, so that the distance between the rangefinders 122 in the first direction changes. The first direction is the arrangement direction between the battery cells 30 connected by the busbar 40.

[0061] The welding device 11 is used to weld the busbar 40 and the pole 31 to connect the two.

[0062] The rangefinder 122 is used to measure the distance between itself and the to-be-welded area 30a on each battery cell 30 in the battery, so as to provide a reference basis for determining the distance between the welding device 11 and the to-be-welded area 30a.

[0063] The to-be-welded area 30a refers to the area on the battery that needs to be welded. For example, the contact area between the pole 31 of the battery cell 30 and the busbar 40.

[0064] It can be understood that the number of rangefinders 122 is multiple, and each rangefinder 122 corresponds to a battery cell 30 respectively, so that each rangefinder 122 separately obtains the distance between the to-be-welded area 30a on the corresponding battery cell 30, thereby reducing the mutual interference between different rangefinders 122.

[0065] The driving component 121 is used to drive the position change of at least some of the rangefinders 122, so that the distance between different rangefinders 122 in the first direction changes accordingly, to adapt to the distance between the to-be-welded areas 30a of each battery cell 30 in different types of batteries in the first direction.

[0066] The first direction, refer toFigure 6 , that is, the arrangement direction between the battery cells 30 connected by the tab 40, refers to the arrangement direction between the two battery cells 30 to which the two terminal posts 31 connected by the tab 40 respectively belong.

[0067] The spacing between the rangefinders 122 along the first direction refers to the spacing between the central positions of the areas for distance measurement of the rangefinders 122 along the first direction.

[0068] The spacing between the areas to be welded 30a of the battery cells 30 refers to the spacing between the central positions of the areas to be welded 30a of the battery cells 30 along the first direction.

[0069] For example, if the spacing between the areas to be welded 30a of the battery cells 30 in the currently required battery to be manufactured along the first direction is all 20 mm (millimeter), then move the same number of rangefinders 122 in the currently required battery to be manufactured to positions where the spacing between them along the first direction is all 20 mm.

[0070] The spacing between the areas to be welded 30a of the battery cells 30 in the battery can be obtained through the design dimensions of the battery itself. Different types of batteries have different design dimensions. According to the type of the currently required battery to be manufactured, obtain its corresponding design dimensions, so as to obtain the spacing between the areas to be welded 30a of the battery cells 30 in the currently required battery to be manufactured along the first direction.

[0071] In the battery welding system according to the embodiment of the present invention, the driving component 121 drives the rangefinder 122 to move, so that the spacing between the rangefinders 122 along the first direction can be changed, so that without disassembling and assembling the rangefinder 122, the spacing between the rangefinders 122 along the first direction corresponds to the spacing between the areas to be welded 30a on the battery along the first direction, thereby improving the efficiency of adjusting the spacing between the rangefinders 122, saving time, reducing the workload, and being beneficial to improving the production efficiency.

[0072] It can be understood that what the rangefinder 122 measures is the spacing between the rangefinder 122 and the area to be welded 30a. Therefore, the measured spacing value needs to be converted to obtain the spacing between the welding device 11 and the area to be welded 30a.

[0073] The battery can be but is not limited to being used in power storage power systems, vehicles, ships, aircraft and other power-consuming devices.

[0074] The battery includes a plurality of battery cells 30. The battery cell 30 can be a secondary battery, and the secondary battery refers to a battery cell 30 that can activate the active material through charging after discharging.

[0075] The battery cell 30 can be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-metal hydride battery, a nickel-cadmium battery, a lead-acid battery, etc., and the embodiments of the present invention are not limited thereto.

[0076] As an example, the battery cell 30 can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell or other shapes. The prismatic battery cell includes a square-shell battery cell, a blade-shaped battery cell, a multi-prismatic battery, and the multi-prismatic battery is, for example, a hexagonal prism battery, etc. The embodiments of the present invention have no special limitations.

[0077] The following will elaborate on the battery welding system in some embodiments of the invention.

[0078] In some embodiments, referring to Figure 2 and Figure 3 , the welding module 10 includes a housing 13. An installation cavity 13a is provided inside the housing 13. The welding device 11 is arranged in the installation cavity 13a. One side of the installation cavity 13a is open to form an avoidance opening 13b, and the welding device 11 can pass through the avoidance opening 13b for welding.

[0079] By arranging the welding device 11 in the installation cavity 13a, on the one hand, the housing 13 provides an installation position for the welding device 11, and on the other hand, the housing 13 can play a certain protective role for the welding device 11, reducing the probability of damage caused by the collision of the welding device 11.

[0080] The avoidance opening 13b provides an operation channel for the welding device 11 to pass through the housing 13 for welding. For example, in an embodiment where the welding device 11 is a laser welding device, the laser emitted by the laser welding device passes through the avoidance opening 13b and irradiates on the area to be welded 30a.

[0081] The specific structural form of the housing 13 is not limited. For example, the housing 13 is formed by splicing a plurality of protective plates to enclose the installation cavity 13a, and the welding device 11 is fixed on at least one of the protective plates.

[0082] The specific material of the protective plate is not limited. For example, stainless steel is used so that the housing 13 has sufficient structural strength to carry the welding device 11.

[0083] In some embodiments, referring to Figure 2The shell 13 is provided with a plurality of through observation holes, which communicate with the installation cavity 13a and the outside of the shell 13. On the one hand, the state of the welding device 11 in the installation cavity 13a can be observed through the observation holes, so that the abnormality of the welding device 11 can be handled in time. At the same time, it is convenient to inspect and maintain the welding device 11 through the observation holes, thereby reducing the probability of installing and removing the welding device 11 from the shell 13 and reducing the workload; on the other hand, the observation holes can play a role in reducing weight.

[0084] In some embodiments, see Figure 2 The avoidance opening 13b is located on the side of the shell 13 away from the connection position between the shell 13 and the robot 20. This is beneficial to increase the swing amplitude of the avoidance opening 13b and to increase the range that the welding module 10 can cover for welding.

[0085] It is understandable that the welding equipment 11 is located near the avoidance opening 13b, which is beneficial to expand the welding range of the welding equipment 11 and reduce the probability of errors, energy loss and other problems caused by the distance between the welding equipment 11 and the area to be welded 30a.

[0086] In some embodiments, see Figure 2 The avoidance opening 13b is located below the shell 13. During the welding process, the laser welding equipment emits laser from top to bottom along the vertical direction to the area to be welded 30a to reduce the interference of other objects around the battery cell to the welding module 10.

[0087] In some embodiments, see Figure 2 , the rangefinder 122 is arranged on the outer surface of the shell 13 and is located at the edge of the avoidance opening 13b. In this way, it is beneficial for the rangefinder 122 to be as close to the area to be welded 30a as possible, thereby improving the measurement accuracy of the rangefinder 122; at the same time, the specific value of the distance between the welding equipment 11 and the area to be welded 30a is converted by calculating the distance value between the rangefinder 122 and the area to be welded 30a, and the rangefinder 122 and the welding equipment 11 are both close to the avoidance opening 13b, which is beneficial for reducing the difference between the distance between the rangefinder 122 and the area to be welded 30a and the distance between the welding equipment 11 and the area to be welded 30a, thereby improving the accuracy of the distance between the welding equipment 11 and the area to be welded 30a, and improving the welding effect. In addition, the rangefinder 122 is located outside the shell 13, which is convenient for debugging the rangefinder 122 and the drive assembly 121.

[0088] In some embodiments, see Figure 2 and Figure 3 The welding module 10 includes a protective shell 16 , which is disposed on the outside of the rangefinder 122 to provide a certain degree of protection for the rangefinder 122 .

[0089] The specific type of the welding device 11 is not limited. For example, the welding device 11 is a laser welding device.

[0090] The laser welding device emits laser to irradiate the area to be welded 30a, so that the materials in the area to be welded 30a are melted, thereby achieving the purpose of welding. The laser welding device is provided with a laser generator and a galvanometer. The laser generator is used to generate laser, and the galvanometer is used to reflect the laser emitted by the laser generator and the reflection surface forms an angle with the laser emitted by the laser generator. By controlling the swing of the galvanometer, the emission angle of the laser reflected by the galvanometer can be changed, so that the welding range is expanded by the galvanometer when the position of the laser generator is fixed.

[0091] It can be understood that during the welding process, due to problems such as impurities in the materials of the area to be welded 30a and uneven heating rate, explosion points may occur in the area to be welded 30a, resulting in the splash of high-temperature foreign matters.

[0092] In some embodiments, referring to Figures 2 to 4 , the welding device 11 is a laser welding device, and the welding module 10 includes a blowing component 14. The blowing component 14 is provided with an air outlet 14a for blowing out air flow. The blowing component 14 is arranged on the emission side of the lens 111 of the laser welding device, and the air outlet 14a faces the laser scanning range 11a of the laser welding device, so as to make the air flow blown out by the air outlet 14a located between the lens 111 and the area to be welded 30a of the battery.

[0093] The lens 111 of the laser welding device means that the laser reflected by the galvanometer passes through the lens 111, and through the convergence of the lens 111, the laser can be condensed in a smaller range, thereby increasing the heating rate of the area to be welded 30a and improving the welding effect.

[0094] It can be understood that the lens 111 is a convex lens so that the laser emitted through the lens 111 can be converged.

[0095] The laser scanning range 11a of the laser welding device refers to the range that the laser can cover after being emitted from the lens 111 through the swing of the galvanometer. It can be understood that the laser scanning range 11a is conical.

[0096] The blowing component 14 is located on the outgoing side of the lens 111, and the air outlet 14a faces the laser scanning range 11a of the laser welding device. In this way, the air flow blown out from the air outlet 14a can form an air curtain between the lens 111 and the area to be welded 30a and pass through the laser scanning range 11a of the laser welding device. The laser can pass through the air curtain and continue welding. At the same time, the high-temperature foreign objects splashed during the welding process can be blown away by the air flow and it is difficult to pass through the air curtain and contact the lens 111, thus playing a protective role for the lens 111 and extending the service life of the lens 111.

[0097] In some embodiments, the air outlet direction of the air outlet 14a is perpendicular to the lens optical axis 11b of the laser welding device.

[0098] The lens optical axis 11b refers to the virtual axis perpendicular to the center of the surface on the outgoing side of the lens 111.

[0099] In this way, the air flow can pass through the laser scanning range 11a. While forming an air curtain between the lens 111 and the area to be welded 30a with the air flow blown out from the air outlet 14a, on the one hand, the probability of the air flow directly blowing on the area to be welded 30a is reduced, and the probability of foreign objects entering the area to be welded 30a due to the blowing of the air flow is reduced, which is beneficial to improving the welding quality; on the other hand, the probability of the air flow directly blowing on the lens 111 is reduced, and the probability of the air flow carrying the splashed high-temperature foreign objects directly contacting the lens 111 is reduced, and the probability of damage to the lens 111 is reduced.

[0100] In some embodiments, referring to Figure 2 and Figure 4 , the number of the blowing components 14 is multiple, and the multiple blowing components 14 are arranged along the extending direction of the lens optical axis 11b of the laser welding device. In this way, multiple air curtains are formed between the lens 111 and the area to be welded 30a, thereby further reducing the probability of the high-temperature foreign objects splashed during the welding process contacting the lens 111 and playing a protective role for the lens 111.

[0101] In some embodiments, referring to Figure 3 , the blowing component 14 is fixed on the welding device 11 so that the blowing component 14 moves synchronously with the welding device 11, and their relative positions and distances are fixed, so that the welding device 11 can be protected by the air flow formed by the blowing component 14 at any position.

[0102] The source of the air flow in the blowing component 14 is not limited. It can be the external main air source on the production line, or it can be that the battery welding system includes an air pump, and the air outlet of the air pump is communicated with the air path in the blowing component 14.

[0103] The specific type of the air flow blown by the air blowing assembly 14 is not limited, such as helium, argon or nitrogen.

[0104] It can be understood that the air outlet 14a can be selectively opened and closed, so that the air outlet timing of the air outlet 14a can be flexibly selected.

[0105] In some embodiments, an air cavity is provided in the air blowing assembly 14. The air cavity is communicated with the air outlet 14a, and the inner wall of the air cavity gradually contracts along the direction close to the air outlet 14a to increase the flow rate of the air flow discharged from the air outlet 14a, thereby enhancing the blocking effect of the air curtain formed by the air flow on the splashing high-temperature foreign objects.

[0106] The specific type of the rangefinder 122 is not limited.

[0107] Exemplarily, referring to Figure 2 and Figure 3 , the rangefinder 122 is a laser rangefinder, and the moving direction of the rangefinder 122 is perpendicular to the lens optical axis 11b of the laser welding device.

[0108] The laser rangefinder has a light emitting area 1221 and a receiving area. Among them, the light emitting area 1221 is used to emit laser light to the welding area 30a to be measured, and the receiving area is used to receive the laser light reflected from the target position.

[0109] During operation, the light emitting area 1221 emits a ranging laser beam to the target. The ranging laser beam irradiates the welding area 30a and is reflected. The reflected ranging laser beam is received by the receiving area, and the timer measures the time from the emission signal to the reception of the ranging laser beam, so as to calculate the distance between the laser rangefinder and the welding area 30a.

[0110] The moving direction of each rangefinder 122 is perpendicular to the lens optical axis 11b of the laser welding device. That is to say, the moving direction of each rangefinder 122 is the same as the arrangement direction of each battery cell 30. In this way, during the movement of the rangefinder 122, the change in the distance between it and the welding area 30a along the extension direction of the lens optical axis 11b is minimized, which is beneficial to reducing the measurement error caused by the change in the position of the rangefinder 122 and improving the measurement accuracy.

[0111] In some embodiments, the direction of the ranging laser beam emitted by the rangefinder 122 is parallel to the lens optical axis 11b of the laser welding device. After the rangefinder 122 completes the measurement of the distance to the welding area 30a, the welding device 11 moves a preset position compensation distance perpendicular to the lens optical axis 11b of the laser welding device between the rangefinder 122 and the lens 111 of the laser welding device, and then welding can be carried out, which is beneficial to reducing the calculation of the distance compensation amount.

[0112] In some embodiments, referring to Figure 2, the light-emitting areas 1221 of the respective distance measuring devices 122 are flush with each other. That is to say, the distances between the light-emitting areas 1221 of the respective distance measuring devices 122 and the area to be welded 30a are relatively small and differ little from each other. In this way, it is beneficial to reduce the difference between the position compensation distances corresponding to different distance measuring devices 122, thereby reducing the computational amount and improving the response speed.

[0113] It can be understood that during the welding process of the welding device 11, there is no need to continue using the distance measuring device 122 for distance measurement.

[0114] In some embodiments, refer to Figure 3 , the welding module 10 includes a first protection component 15. The first protection component 15 includes a first baffle 151 and a first driving member 152. The driving end of the first driving member 152 is drivingly connected to the first baffle 151 so that the first baffle 151 can selectively cover the light-emitting area 1221 of the distance measuring device 122.

[0115] The first protection component 15 includes a covering state and an open state. In the open state, the welding module 10 is in the distance measuring position, and the distance measuring device 122 can measure the distance between it and the area to be welded 30a; in the covering state, the first driving member 152 drives the first baffle 151 to move to a suitable position so that the first baffle 151 covers the light-emitting area 1221.

[0116] In this way, during the welding process of the welding device 11, the first baffle 151 can protect the light-emitting area 1221 of the distance measuring device 122, reducing the probability that high-temperature foreign objects splashed during the welding process adhere to the light-emitting area 1221 of the distance measuring device 122, thereby reducing the probability of damage to the distance measuring device 122.

[0117] The specific type of the first driving member 152 is not limited, such as a slide cylinder, etc.

[0118] In some embodiments, refer to Figure 3 , in the covering state, in the direction perpendicular to the distance measuring laser beam emitted by the distance measuring device 122, the projections of the respective distance measuring devices 122 are all within the projection range of the first baffle 151. In this way, the protection of each distance measuring device 122 can be achieved only by one first baffle 151, thereby simplifying the structure of the first protection component 15 and reducing the number of components.

[0119] The specific structure of the driving component 121 is not limited.

[0120] Exemplarily, refer to Figure 5, the driving assembly 121 includes a driving motor 1211, a lead screw 1212, a guide rail 1213, and a slider 1214. The driving end of the driving motor 1211 is drivingly connected to one end of the lead screw 1212. The slider 1214 is slidably engaged with the guide rail 1213. The guide rail 1213 is in the same extending direction as the lead screw 1212. At least one rangefinder 122 is disposed on the slider 1214. In this way, by driving the lead screw 1212 to rotate with the driving motor 1211 and the screw-thread engagement between the lead screw 1212 and the slider 1214, the movement of the rangefinder 122 located on the slider 1214 is realized, and further the purpose of changing the distance between the rangefinders 122 is achieved.

[0121] In some embodiments, referring to Figure 2 , the extending direction of the lead screw 1212 is perpendicular to the lens optical axis 11b of the laser welding device, so that the movement direction of the rangefinder 122 is perpendicular to the lens optical axis 11b of the laser welding device.

[0122] It can be understood that the number of battery cells 30 and tabs 40 to be welded in the battery is multiple. Therefore, it is necessary to move the welding module 10 to adapt to the positions of different battery cells 30 and tabs 40.

[0123] In some embodiments, referring to Figure 1 , the battery welding system includes a robot 20. The execution end 21 of the robot 20 is drivingly connected to the welding module 10 to drive the welding module 10 to move to the welding position to weld the area to be welded 30a.

[0124] The robot 20 is provided with a plurality of joint axes. Each joint axis is correspondingly configured with a servo motor. The servo motor directly drives the rotation of the joint axis through a speed reducer, a synchronous belt pulley, etc., so as to achieve the purpose that the execution end 21 at the outermost end of the robot 20 has multiple degrees of freedom in space.

[0125] The robot 20 is used to drive the whole welding module 10 to move, so that the welding module 10 can reach the position where ranging is required. At the same time, when the welding module 10 does not need to be welded, it can drive the whole welding module 10 to move away from the conveyor line for conveying the battery, reducing the probability of collision; or, when overhauling the welding module 10, move the welding module 10 to a suitable position for easy operation.

[0126] The robot 20 can flexibly move in various trajectories and angles in space, which is convenient for the welding module 10 to avoid other surrounding objects during movement. At the same time, it is beneficial for the welding module 10 to weld the area to be welded 30a from a suitable angle, thereby improving the welding quality.

[0127] In some embodiments, referring to Figure 1 and Figure 2, the execution end 21 of the robot 20 is fixedly connected to the housing 13.

[0128] It can be understood that it is necessary to move the welding module 10 to a suitable ranging position in advance by the robot 20 and then perform ranging through the rangefinder 122.

[0129] In some embodiments, refer to Figure 2 and Figure 3 , the welding module 10 includes a vision measurement component 17, and the vision measurement component 17 is used to capture an image of the area to be welded 30a to calculate the relative position between the welding module 10 and the area to be welded 30a.

[0130] The vision measurement component captures an image of the area to be welded 30a and sends the acquired image data to the control device corresponding to the battery welding system. The control device calculates the relative position between the welding module 10 and the area to be welded 30a after calculating the image data, so as to calculate the displacement and direction that the welding module 10 needs to move.

[0131] The specific type of the vision measurement component 17 is not limited, such as a CCD (Charge Coupled Device) camera.

[0132] The shooting end of the vision measurement component 17 is on the same side as the lens 111 and has the same orientation.

[0133] In some embodiments, refer to Figure 3 , the welding module includes a second protection component 18, and the second protection component 18 includes a second baffle 181 and a second driving member 182. The driving end of the second driving member 182 is drivingly connected to the second baffle 181 so that the second baffle 181 can selectively cover the light-emitting area of the rangefinder. In this way, during the welding process of the welding device 11, the second baffle can protect the shooting end of the vision measurement component 17, reducing the probability that high-temperature foreign objects splashed during the welding process adhere to the shooting end of the vision measurement component 17, thereby reducing the probability of damage to the vision measurement component 17.

[0134] In some embodiments, the battery welding system further includes:

[0135] A conveying module for conveying the battery to be welded to the welding operation position;

[0136] A positioning module for fixing the positions of the battery cell 30 and the tab 40 after the battery reaches the welding operation position;

[0137] A pressing plate module for pressing against the tab 40 after the positions of the battery cell 30 and the tab 40 are fixed, so that the tab 40 is attached to the pole 31.

[0138] The conveying module places the battery to be welded. Through the conveying module, the battery to be welded is moved until it reaches the welding operation position.

[0139] The welding operation position is the position where the battery is located during the welding process by the welding module.

[0140] The specific type of the conveying module is not limited, such as a conveyor belt, an AGV (Automated Guided Vehicle), etc.

[0141] The positioning module fixes the positions of the battery cell 30 and the tab 40 to reduce the probability of welding failure caused by the relative position change between the battery cell 30 and the tab 40 during subsequent welding.

[0142] The pressing plate module abuts against the tab 40 to keep the tab 40 in contact with the pole 31, reducing the probability of separation between the tab 40 and the pole 31 during welding, which is beneficial to improving the welding quality.

[0143] In this way, through the cooperation between the conveying module, the positioning module, the pressing plate module and the welding module, the battery can be successfully welded and the welding quality can be improved.

[0144] Refer to Figures 1 to 5 , the battery welding system in an embodiment of the present invention is specifically described as follows:

[0145] The battery welding system includes a robot 20, a welding module 10, a conveying module, a positioning module, and a pressing plate module. The welding module 10 includes a housing 13, a laser welding device, a blowing component 14, a rangefinder 122, a driving component 121, and a first protection component 15. The execution end 21 of the robot 20 is connected to the housing 13. An installation cavity 13a is provided inside the housing 13, and the laser welding device is arranged in the installation cavity 13a. One side of the installation cavity 13a away from the execution end 21 is open to form an avoidance opening 13b. The rangefinder 122 is arranged on the outer surface of the housing 13 and is located at the edge of the avoidance opening 13b. The blowing component 14 is arranged on the emission side of the lens 111 of the laser welding device, and the air outlet 14a faces the laser scanning range 11a of the laser welding device. The air outlet direction of the air outlet 14a is perpendicular to the lens optical axis 11b of the laser welding device. The driving component 121 includes a driving motor 1211, a lead screw 1212, a guide rail 1213, and a slider 1214. The driving end of the driving motor 1211 is drivingly connected to one end of the lead screw 1212. The slider 1214 is slidably matched with the guide rail 1213. The guide rail 1213 is in the same extending direction as the lead screw 1212. At least one rangefinder 122 is arranged on the slider 1214 to drive the rangefinder 122 to move. The moving direction of the rangefinder 122 is perpendicular to the lens optical axis 11b of the laser welding device. The rangefinder 122 is a laser rangefinder. The direction of the ranging laser beam emitted by the rangefinder 122 is parallel to the lens optical axis 11b of the laser welding device, and the light-emitting areas 1221 of the rangefinders 122 are flush with each other. The first protection component 15 includes a first baffle 151 and a first driving member 152. The driving end of the first driving member 152 is drivingly connected to the first baffle 151, so that the first baffle 151 can selectively cover the light-emitting area 1221 of the rangefinder 122. The conveying module is used to convey the battery to be welded to the welding operation position. The positioning module is used to fix the positions of the battery cell 30 and the tab 40 after the battery reaches the welding operation position. The pressing plate module is used to press against the tab 40 after the positions of the battery cell 30 and the tab 40 are fixed, so that the tab 40 is attached to the pole 31.

[0146] An embodiment of the present invention further provides a control method for a battery welding system, which is applied to a control device. The specific type of the control device is not limited, such as a PLC (Programmable Logic Controller) device, an industrial control computer, etc. Refer to Figure 7 , and this control method includes:

[0147] Step S01: Control the robot to drive the welding module to move to the ranging position.

[0148] The ranging position means that after the welding module 10 reaches this position, the distance between the rangefinder 122 and the position to be welded can be measured by the rangefinder 122.

[0149] Step S02: Obtain the distance between the welding areas to be welded of adjacent battery cells in the battery, and control the driving component to drive the rangefinder to move so that the distance between the rangefinders corresponds to the distance between the welding areas to be welded of the battery cells.

[0150] The distance between the welding areas 30a to be welded of adjacent battery cells 30 in the battery is the designed size of the battery. The distances between the welding areas 30a to be welded of adjacent battery cells 30 in different types of batteries are different, and the distance values of each type of battery are pre-stored in the storage unit of the control device. According to the type of battery currently being produced, obtain the distance between the welding areas 30a to be welded of adjacent battery cells 30 in the currently produced battery from the storage unit.

[0151] In this way, the welding area 30a of each battery cell 30 can be covered by the measurement range of one measuring instrument.

[0152] Step S03: Control each rangefinder to measure the distance value between it and the welding area to be welded of the corresponding battery cell.

[0153] Step S04: Calculate the defocus compensation distance for welding the welding areas to be welded of each battery cell according to the focal length of the laser welding equipment and each distance measurement value.

[0154] It can be understood that the focal length of the lens 111 of the laser welding equipment is fixed, and for the welding areas 30a of different types of batteries, due to the change in the size of the battery, their distances from the lens 111 of the laser welding equipment are different.

[0155] It can be understood that since the lens 111 of the laser welding equipment and the rangefinder 122 are not located at the same position, it is necessary to obtain the defocus compensation distance by additionally combining the focal length of the laser welding equipment and each distance measurement value according to the azimuth deviation between the two positions.

[0156] When the rangefinder 122 is a laser rangefinder, the moving direction of the rangefinder 122 is perpendicular to the optical axis 11b of the lens of the laser welding equipment, and the direction of the ranging laser beam emitted by the rangefinder 122 is parallel to the optical axis 11b of the lens of the laser welding equipment, the distance and angle between the lens 111 of the laser welding equipment and the rangefinder 122 along the direction of the optical axis 11b remain unchanged. Therefore, this rated parameter is pre-stored in the storage unit of the control device to obtain the defocus compensation distance by combining the focal length of the laser welding equipment and each distance measurement value.

[0157] Step S05: According to each defocus compensation distance, control the robot to drive the welding module to move to the welding position corresponding to the welding area to be welded of each battery cell.

[0158] The welding position is the position where the laser welding equipment emits laser for welding.

[0159] In this way, after the laser emitted by the laser welding device is converged by the lens 111, the converged focal point is located in the area to be welded 30a, so as to converge as much laser energy as possible on the area to be welded 30a and improve the welding effect.

[0160] Step S06: Control the laser welding device to perform welding.

[0161] Through the above control method, the battery welding system can adaptively adjust the positions of the respective rangefinders 122 for different types of batteries to obtain the actual distance between the laser welding device and the area to be welded 30a on the battery. Taking this as a reference, it is convenient to move the laser welding device to achieve the purpose that the focal point of the laser welding device is located near the area to be welded 30a, which is conducive to improving the welding quality.

[0162] In some embodiments, before controlling the laser welding device to perform welding, the control method further includes:

[0163] Control the air blowing assembly 14 to be turned on so as to form an air curtain between the lens 111 of the laser welding device and the battery.

[0164] In this way, the probability that the lens 111 is damaged due to contact with splashing high-temperature foreign matters during the welding process of the laser welding device is reduced.

[0165] The various embodiments / implementations provided by the present invention can be combined with each other without conflict.

[0166] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the embodiments of the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A battery welding system for welding between the pole columns of different battery monomers in a battery through a tab, characterized in that, Comprising: A welding module, the welding module includes a welding device, a driving component, a vision measurement component and a plurality of rangefinders. The welding device is used to weld the tab and the terminal post. At least part of the rangefinders are drivingly connected to the driving end of the driving component. The driving component drives the rangefinders to move in a first direction, so that the spacing between the rangefinders in the first direction changes. The first direction is the arrangement direction between the battery cells connected by the tab. The vision measurement component is used to capture an image of the area to be welded.

2. The battery welding system according to claim 1, wherein The welding module includes a housing, an installation cavity is provided in the housing, the welding device is arranged in the installation cavity, one side of the installation cavity is open to form an avoidance opening, and the welding device can pass through the avoidance opening for welding.

3. The battery welding system according to claim 2, wherein, The rangefinder is arranged on the outer surface of the housing and is located at the edge of the avoidance opening; And / or, the vision measurement component is arranged in the installation cavity.

4. The battery welding system according to claim 1, wherein, The welding device is a laser welding device. The welding module includes a blowing component. The blowing component is provided with an air outlet for blowing out air flow. The blowing component is arranged on the emitting side of the lens of the laser welding device, and the air outlet faces the laser scanning range of the laser welding device, so as to make the air flow blown out by the air outlet located between the lens and the area to be welded of the battery.

5. The battery welding system according to claim 4, wherein, The air outlet direction of the air outlet is perpendicular to the optical axis of the lens of the laser welding device.

6. The battery welding system according to claim 4, characterized in that The number of the blowing components is multiple, and the multiple blowing components are arranged along the extending direction of the optical axis of the lens of the laser welding device.

7. The battery welding system according to claim 4, wherein, The rangefinder is a laser rangefinder, and the moving direction of the rangefinder is perpendicular to the optical axis of the lens of the laser welding device.

8. The battery welding system according to claim 7, characterized in that, The direction of the ranging laser beam emitted by the rangefinder is parallel to the optical axis of the lens of the laser welding device; And / or, the light-emitting areas of the rangefinders are flush with each other.

9. The battery welding system according to claim 7, wherein The welding module includes a first protection component, the first protection component includes a first baffle and a first driving member, and the driving end of the first driving member is drivingly connected to the first baffle, so that the first baffle can selectively cover the light-emitting area of the rangefinder.

10. The battery welding system according to claim 4, wherein The vision measurement component and the rangefinder are arranged at intervals, the welding device is located between the vision measurement component and the rangefinder, the blowing component is located on one side of the welding device perpendicular to the relative direction of the vision measurement component and the rangefinder, and the air outlet is lower than the vision measurement component and the rangefinder.

11. The battery welding system according to claim 1, characterized in that The driving component includes a driving motor, a lead screw, a guide rail and a slider. The driving end of the driving motor is drivingly connected to one end of the lead screw. The slider is slidably matched with the guide rail. The guide rail is in the same extending direction as the lead screw. At least one rangefinder is arranged on the slider.

12. The battery welding system according to claim 1, wherein, The battery welding system includes a robot, and the execution end of the robot is drivingly connected to the welding module to drive the welding module to move to the welding position to weld the area to be welded.

13. The battery welding system according to claim 1, wherein The battery welding system further includes: A conveying module for conveying the battery to be welded to the welding operation position; The positioning module is used to fix the positions of the battery cell and the tab after the battery reaches the welding operation position; The pressing plate module is used to press on the tab after the positions of the battery cell and the tab are fixed, so that the tab is attached to the pole column.

14. A control method for a battery welding system, characterized in that, The control method includes: Controlling the robot to drive the welding module to move to the ranging position; Obtaining the distance between the to-be-welded areas of adjacent battery cells in the battery, and controlling the driving component to drive the rangefinder to move, so that the distance between the rangefinders corresponds to and is equal to the distance between the to-be-welded areas of the battery cells; Controlling each of the rangefinders to measure the ranging value between it and the corresponding to-be-welded area of each of the battery cells; Calculating the defocus compensation distance for welding the to-be-welded areas of each of the battery cells according to the focal length of the laser welding equipment and each of the ranging values; According to each of the defocus compensation distances, controlling the robot to drive the welding module to move to the welding position corresponding to the to-be-welded area of each of the battery cells; Controlling the laser welding equipment to perform the welding operation.

15. The control method according to claim 14, wherein Before controlling the laser welding equipment to perform the welding operation, the control method further includes: Controlling the air blowing component to be turned on, so as to form an air curtain between the lens of the laser welding equipment and the battery.

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