A welding system and welding method

Abstract

This application provides a welding system and welding method. The welding system is used to weld multiple battery cells to conductive connectors. The welding system includes a container and multiple branch pipes. The container is used to hold liquid solder, and the branch pipes are configured to deliver the liquid solder to the welding sites between the battery cells and the conductive connectors. The welding system of this application embodiment simultaneously delivers liquid solder to the welding sites between the battery cells and the conductive connectors through multiple branch pipes, thereby achieving parallel welding of multiple battery cells to the conductive connectors, which helps to improve welding efficiency and thus improve battery production efficiency. Furthermore, if the number of branch pipes is the same as the number of terminals, the welding of all battery cells' terminals to the conductive connectors within the battery can be achieved at once, thereby further shortening the welding time and further improving battery production efficiency.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a welding system and welding method. Background Technology

[0002] Currently, the application of power batteries is becoming increasingly widespread. A crucial step in the production of power batteries is welding conductive connecting pieces to the terminals of multiple battery cells to achieve series and parallel connections between these cells, thereby integrating them into a battery module and / or battery pack.

[0003] In related technologies, when welding conductive connecting pieces to the terminals of battery cells, the welding efficiency is low due to factors such as the large number of battery cells to be welded and the limited welding equipment, which in turn affects the production efficiency of the battery. Summary of the Invention

[0004] This application is made in view of the above-mentioned issues, and its purpose is to provide a welding system and welding method to improve the welding efficiency between conductive connecting pieces and battery cells.

[0005] The first aspect of this application provides a welding system for welding multiple battery cells to conductive connectors. The welding system includes a container and multiple branch lines. The container holds liquid solder, and the branch lines are configured to deliver the liquid solder to the areas to be welded between the battery cells and the conductive connectors.

[0006] The welding system of this application embodiment simultaneously delivers liquid solder to the welding locations of battery cells and conductive connecting pieces via multiple branch pipes, thereby achieving parallel welding of multiple battery cells and conductive connecting pieces. After the terminals of multiple battery cells are attached to the conductive connecting pieces, the nozzle of each branch pipe simultaneously moves to the welding location, i.e., the terminal. Because the pipes are long and slender, the nozzle size can be designed to match the size of the terminal, so multiple branch pipes can be located at the welding location simultaneously. The container contains molten liquid solder, which can be molten aluminum alloy, molten aluminum, etc. The liquid solder flows along the branch pipes to the welding location. After the liquid solder solidifies, parallel welding of the terminals of multiple battery cells and conductive connecting pieces is achieved, thereby improving welding efficiency and thus improving battery production efficiency.

[0007] Furthermore, if the number of branch pipes is the same as the number of terminals, the terminals and conductive connecting pieces of all battery cells in the battery can be welded at once, thereby further shortening the welding time and improving the battery production efficiency.

[0008] In some embodiments of this application, the welding system further includes a main delivery pipeline, one end of which is connected to a container and the other end of which is connected to a plurality of branch pipelines.

[0009] By setting up a main pipeline, the length of branch pipelines can be reduced, which facilitates the maintenance and management of multiple branch pipelines.

[0010] In some embodiments of this application, the welding system further includes a protective gas delivery line connected to the container, the protective gas delivery line being configured to deliver protective gas to the container.

[0011] By setting up a protective gas delivery pipeline to deliver protective gas into the container, it is beneficial to prevent the liquid solder from being oxidized during transportation, which would affect the welding effect.

[0012] In some embodiments of this application, the welding system further includes a drive device configured to drive liquid solder in the container to deliver it to multiple branch lines.

[0013] By setting up a drive device, the liquid solder in the container can be more easily flowed to the branch pipes, and then to the part to be welded for welding.

[0014] Furthermore, the drive unit is located between the main delivery pipeline and multiple branch pipelines.

[0015] By installing a drive device between the branch pipeline and the main delivery pipeline, the length of the branch pipeline can be reduced, making it easier to maintain and repair the branch pipeline. On the other hand, it also makes it easier for the liquid solder in the container to flow to the part to be welded.

[0016] In some embodiments of this application, the welding system further includes an image acquisition device and a controller. The image acquisition device is used to acquire image information of the branch pipe, battery cell and conductive connector. The controller is configured to receive the image information and determine whether the end of the branch pipe is located at the part to be welded based on the image information.

[0017] By setting up image acquisition equipment, image information of branch pipelines, battery cells and conductive connectors can be acquired in real time.

[0018] By setting up image acquisition equipment and controllers, it is possible to monitor in real time whether the branch pipeline is located at the welding position, thereby improving the intelligence and informatization of the welding system.

[0019] In some embodiments of this application, the welding system further includes a positioning plate, to which each branch pipe is fixedly connected.

[0020] By setting a positioning plate and fixing multiple branch pipes to the positioning plate, the positional relationship between the multiple branch pipes and the part to be welded can be adjusted by moving the positioning plate, thereby improving the convenience of adjusting the position of the multiple branch pipes.

[0021] In some embodiments of this application, a control valve is provided at the end of each branch pipe.

[0022] By setting control valves, it is beneficial to control the flow rate of liquid solder at the end of the branch pipeline as well as its opening and closing, thereby helping to control the amount of liquid solder in the part to be welded, and thus helping to control the consistency of welding.

[0023] A second aspect of this application provides a welding method based on the aforementioned welding system. The welding method includes:

[0024] Provides multiple battery cells and conductive connectors;

[0025] Add liquid solder to the container;

[0026] Liquid solder is delivered to the terminals and conductive connectors of the battery cells through branch pipelines.

[0027] The welding method of this application embodiment is based on a welding system. This welding method simultaneously delivers liquid solder to the welding locations of battery cells and conductive connecting pieces via multiple branch pipes, thereby achieving parallel welding of multiple battery cells and conductive connecting pieces. After the terminals of multiple battery cells are attached to the conductive connecting pieces, the nozzle of each branch pipe simultaneously moves to the welding location, i.e., the terminal. Because the pipes are long and slender, the nozzle size can be designed to fit the size of each terminal, thus allowing multiple branch pipes to be located at the welding locations simultaneously. The container contains molten liquid solder, which can be molten aluminum alloy, molten aluminum, etc. The liquid solder flows along the branch pipes to the welding locations. After the liquid solder solidifies, parallel welding of the terminals of multiple battery cells and conductive connecting pieces is achieved, thereby improving welding efficiency and ultimately increasing battery production efficiency.

[0028] Furthermore, if the number of branch pipes is the same as the number of terminals, the terminals and conductive connecting pieces of all battery cells in the battery can be welded at once, thereby further shortening the welding time and improving the battery production efficiency.

[0029] In some embodiments of this application, after the step of adding liquid solder to the container, the welding method further includes adding a protective gas to the container.

[0030] By setting up a protective gas delivery pipeline to deliver protective gas into the container, it is beneficial to prevent the liquid solder from being oxidized during transportation, which would affect the welding effect.

[0031] In some embodiments of this application, a cavity is provided on the electrode post, and a through hole is provided on the conductive connecting piece opposite to the cavity. The step of conveying liquid solder to the electrode post and the conductive connecting piece of the battery cell to be soldered through a branch pipeline includes:

[0032] Liquid solder is delivered to the cavity on the electrode post and the through hole on the conductive connector through branch lines.

[0033] A cavity is a structure that has a cavity to accommodate a passage, and a through hole allows branch pipes to pass through.

[0034] A cavity is provided on the pole and a through hole is provided on the conductive connector at the position corresponding to the cavity. In this way, the branch pipe can be inserted into the cavity through the through hole, which facilitates the positioning of the branch pipe. At the same time, the cavity can also hold liquid solder, which also helps to prevent liquid solder from overflowing.

[0035] In some embodiments of this application, the welding system further includes an image acquisition device and a controller, and the welding method further includes:

[0036] Image acquisition equipment acquires image information of branch pipelines, battery cells, and conductive connectors;

[0037] The controller receives image information and determines whether the end of the branch pipe is located at the part to be welded based on the image information.

[0038] Image acquisition equipment and controllers can help monitor in real time whether branch pipes are located at the welding position, thereby improving the intelligence and informatization of the welding system.

[0039] In some embodiments of this application, the welding method further includes:

[0040] An exhaust hole communicating with a through hole is provided on the conductive connecting piece.

[0041] By setting vent holes, the gas that was originally present in the cavity can be discharged through the vent holes when the liquid solder is injected into the cavity, which helps to improve the welding effect. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other embodiments can be obtained based on these drawings.

[0043] Figure 1 This is a schematic diagram of the welding system according to an embodiment of this application;

[0044] Figure 2 This is a schematic diagram of a battery, a battery cell, and a conductive connecting piece according to an embodiment of this application;

[0045] Figure 3 This is a structural exploded diagram of a battery cell.

[0046] Figure 4 for Figure 2 A schematic diagram of a partial cross-section cut along section AA.

[0047] Figure 5 for Figure 2 Enlarged view of point B in the middle;

[0048] Figure 6 This is a schematic diagram of the image acquisition device and its controller;

[0049] Figure 7 This is a flowchart of a welding method according to an embodiment of this application.

[0050] Figure label:

[0051] Welding system-10; Battery-90; Battery cell-100; Terminal post-20; End cap-21; Housing-22; Electrode assembly-23; Part to be welded-24; Cavity-25; Through hole-26; Vent hole-27; Conductive connecting piece-110; Container-120; Branch pipeline-130; Solid solder-140; Liquid solder-141; Main delivery pipeline-150; Protective gas delivery pipeline-160; Drive device-170; Image acquisition equipment-180; Controller-190; Positioning plate-200. Detailed Implementation

[0052] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0054] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0055] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0056] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0057] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0058] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0059] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0060] Currently, the application of power batteries is becoming increasingly widespread. A crucial step in the production of power batteries is welding conductive connecting pieces to the terminals of multiple battery cells to achieve series and parallel connections between these cells, thereby integrating them into a battery module and / or battery pack.

[0061] In related technologies, the welding efficiency is low when welding conductive connecting pieces to the terminals of battery cells due to factors such as the large number of battery cells to be welded, the large size of the welding equipment, and the limited number of welding devices. This, in turn, affects the battery production efficiency. For example, when welding multiple battery cells to conductive connecting pieces within a battery, the close arrangement of the battery cells, the limited size of the welding fixture, and the limited number of welding devices necessitate dividing the battery cells into several groups for serial welding. Furthermore, when welding the terminals of the battery cells within each group to the conductive connecting pieces, the welding head may need to weld the terminals of the battery cells within that group sequentially. This effectively takes many times longer to complete the welding of a battery module or battery pack, thus hindering the improvement of battery production efficiency.

[0062] Based on the above, the applicant, after in-depth research, designed a welding system capable of simultaneously welding multiple battery cells within a battery. This system allows for the parallel welding of battery cells to conductive connectors, thereby improving battery production efficiency. Furthermore, it can even complete the welding of all battery cell terminals and conductive connectors in a single operation, further enhancing welding efficiency.

[0063] This application also proposes a welding method based on this welding system, which facilitates the parallel welding of battery cells and conductive connecting pieces within the battery, thereby improving battery production efficiency.

[0064] The welding system of this application embodiment can be used, but is not limited to, for parallel welding of batteries and conductive connecting pieces.

[0065] The battery mentioned in this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include a battery module or battery pack. A battery generally includes a housing for encapsulating one or more battery cells. The housing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells. Specifically, the housing may include a top cover and a casing, which are fastened together. The shape of the top cover and casing may be determined based on the shape of the combination of multiple battery cells.

[0066] Multiple battery cells can be connected in series and / or parallel by welding terminals and conductive connecting pieces for various applications. Using the welding system of this application embodiment improves the welding efficiency of terminals and conductive connecting pieces, thereby enhancing battery production efficiency. In high-power applications such as electric vehicles, battery applications involve three levels: battery cells, battery modules, and battery packs. Battery modules are formed by electrically connecting a certain number of battery cells together and placing them in a frame to protect them from external impacts, heat, vibration, etc. Battery packs are the final state of the battery system installed in electric vehicles. Currently, most battery packs are made by assembling a battery management system (BMS), thermal management components, and other control and protection systems onto one or more battery modules. With technological advancements, the battery module level can be omitted, meaning that battery packs can be formed directly from battery cells. This improvement increases the gravimetric and volumetric energy density of the battery system while significantly reducing the number of components. The battery mentioned in this application includes battery modules or battery packs.

[0067] The battery cells mentioned in this application embodiment may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and this application embodiment is not limited to these. Battery cells may be cylindrical, flat, cuboid, or other shapes, and this application embodiment is not limited to these shapes either. Battery cells are generally classified into three types according to their packaging method: cylindrical battery cells, cuboid / square battery cells, and pouch battery cells, and this application embodiment is not limited to these types either.

[0068] The first aspect of this application provides a welding system 10 for welding multiple battery cells 100 to conductive connecting pieces 110. For example... Figure 1 and Figure 2 As shown, the welding system 10 includes a container 120 and multiple branch lines 130. The container 120 is used to hold liquid solder 141, and the branch lines 130 are configured to deliver the liquid solder 141 to the welding site 24 between the battery cell 100 and the conductive connector 110.

[0069] like Figure 3As shown, a battery cell 100 refers to the smallest unit that enables the charging and discharging function of battery 90. A battery cell 100 typically includes terminals 20, end caps 21, a housing 22, electrode assemblies 23, and other functional components, such as an insulating layer. Terminals 20 are components electrically connected to the positive or negative terminal within battery 90. Typically, a battery cell 100 has two terminals 20, generally used for connection to the terminals 20 of adjacent cells 90 within battery 90 via conductive connecting pieces 110. Common materials for terminals 20 include lead, brass plating, copper plating, or copper. End caps 21 are components that cover the opening of housing 22 to isolate the internal environment of battery cell 100 from the external environment. Functional components such as terminals 20 may be provided on end caps 21. Housing 22 is a component used to house electrode assemblies 23 to form battery cell 100. The shape of end caps 21 may be adapted to the shape of housing 22 to fit the housing 22. The casing 22 also contains an electrolyte and other components. The casing 22 can be made of various materials, such as iron, aluminum, or stainless steel. The electrode assembly 23 is the component in the battery cell 100 where the electrochemical reaction occurs. The casing 22 may contain one or more electrode assemblies 23. The electrode assembly 23 is mainly formed by winding or stacking positive and negative electrode plates, and a separator is usually provided between the positive and negative electrode plates.

[0070] The conductive connector 110 refers to a conductive structure used to connect multiple battery cells 100 in series and / or parallel. Typically, the conductive connector 110 is connected to the terminal post 20 of the battery cell 100 by welding. Common conductive connectors 110 include nickel-plated copper connectors, pure nickel connectors, and nickel-plated steel connectors.

[0071] like Figure 2 As shown, the part to be welded 24 can be the part that needs to be welded after the conductive connecting piece 110 is attached to the terminal post 20 of multiple battery cells 100. After welding, the multiple battery cells 100 become a whole through the conductive connecting piece 110.

[0072] The container 120 is a container for holding liquid solder 141, and its shape is not limited. The container 120 may simply be a container for holding the melted liquid solder 141, or it may be a high-temperature furnace that includes a furnace to heat the solid solder 140 and melt it into liquid solder 141.

[0073] Branch pipes 130 are connected to container 120, so that liquid solder 141 can flow from multiple branch pipes 130 to the part 24 to be soldered.

[0074] The welding system 10 of this application embodiment utilizes multiple branch pipes 130 to simultaneously deliver liquid solder 141 to the welding positions 24 of the battery cells 100 and the conductive connecting pieces 110, thereby achieving parallel welding of multiple battery cells 100 and conductive connecting pieces 110. After the terminals 20 of the multiple battery cells 100 of the battery 90 are attached to the conductive connecting pieces 110, the nozzles of each branch pipe simultaneously move to the welding position 24, i.e., the terminal 20. Since the pipes are elongated, the nozzle size can be designed to match the size of the terminal 20, so multiple branch pipes 130 can be simultaneously located at the welding positions 24. The container 120 contains molten liquid solder 141, which can be molten aluminum alloy, molten aluminum, etc. Liquid solder 141 can flow into the part 24 to be welded along the branch pipe. After the liquid solder 141 solidifies, the pole post 20 of multiple battery cells 100 can be welded to the conductive connecting piece 110 in parallel, which helps to improve welding efficiency and thus improve the production efficiency of battery 90.

[0075] Furthermore, if the number of branch pipes 130 is the same as the number of terminals 20, then the terminals 20 and conductive connecting pieces 110 of all battery cells 100 in the battery 90 can be welded at once, thereby further shortening the welding time and improving the production efficiency of the battery 90.

[0076] like Figure 1 As shown, in some embodiments of this application, the welding system 10 further includes a main delivery pipeline 150, one end of which is connected to the container 120, and the other end of which is connected to a plurality of branch pipelines 130.

[0077] The main delivery pipeline 150 is relative to the branch pipelines 130; that is, the branch pipelines 130 are branches of the main delivery pipeline 150. Liquid solder 141 first flows through the main delivery pipeline 150, and then branches off from the main delivery pipeline 150 to multiple branch pipelines 130. The material of the main delivery pipeline 150 can be a high-temperature resistant and heat-insulating material, which helps to prevent the liquid solder 141 from damaging the pipeline or from prematurely solidifying due to cooling.

[0078] By setting up the main pipeline 150, the length of the branch pipelines 130 can be reduced, which facilitates the maintenance and management of multiple branch pipelines 130.

[0079] like Figure 1 As shown, in some embodiments of this application, the welding system 10 further includes a protective gas delivery line 160 connected to the container 120, the protective gas delivery line 160 being configured to deliver protective gas to the container 120.

[0080] The protective gas delivery pipeline 160 refers to the channel used to deliver the protective gas. The protective gas is a chemically stable gas that does not easily react with the protected material, which in this case is liquid solder 141. Common protective gases include helium, neon, and argon.

[0081] By setting up a protective gas delivery pipeline 160 to deliver protective gas into the container 120, it is beneficial to prevent the liquid solder 141 from being oxidized or contaminated during the delivery process, thereby affecting the welding effect.

[0082] like Figure 1 As shown, in some embodiments of this application, the welding system 10 further includes a drive device 170 configured to drive liquid solder 141 in the container 120 to a plurality of branch lines 130.

[0083] The drive device 170 refers to a device that can provide a power source, such as a hydraulic pump for driving liquid transmission, specifically, a vane pump, a piston pump, and a gear pump; or a device for pressurizing the container 120, thereby making it easier for the liquid solder 141 to flow through the branch pipe 130 to the part to be welded 24 by pressurizing the container 120.

[0084] By providing the drive device 170, the liquid solder 141 in the container 120 can be more easily flowed to the branch pipe 130, and then to the part 24 to be welded for welding.

[0085] Furthermore, the drive unit 170 is located between the main delivery pipeline 150 and the multiple branch pipelines 130.

[0086] By installing a drive device 170 between the branch pipeline 130 and the main delivery pipeline 150, the length of the branch pipeline 130 can be reduced, making it easier to maintain the branch pipeline 130. On the other hand, it also makes it easier for the liquid solder 141 in the container 120 to flow to the part 24 to be welded.

[0087] like Figure 6 As shown, in some embodiments of this application, the welding system 10 further includes an image acquisition device 180 and a controller 190. The image acquisition device 180 is used to acquire image information of the branch pipe 130, the battery cell 100, and the conductive connecting piece 110; the controller 190 is configured to receive the image information and determine whether the end of the branch pipe 130 is located at the part 24 to be welded based on the image information.

[0088] Image acquisition device 180 refers to equipment with camera and photographing functions. In the industrial sector, image acquisition device 180 can be an industrial camera. Industrial cameras have high image stability, high transmission capacity, and high anti-interference capability. Most common industrial cameras are based on photocoupled device (CCD) chips, which can acquire image information of the object being photographed in real time.

[0089] By setting up the image acquisition device 180, image information of the branch pipe 130, battery cell 100 and conductive connecting piece 110 can be acquired in real time.

[0090] In this embodiment, the controller 190 is paired with the image acquisition device 180. The controller 190 can receive image information from the image acquisition device 180 and determine whether the end of the branch pipe 130 is located at the welding part 24 based on the image information. The controller 190 and the image acquisition device 180 can realize the determination of the status of the factory production line by using machines instead of human eyes, which is more accurate and convenient.

[0091] By setting up image acquisition device 180 and controller 190, it is beneficial to monitor in real time whether branch pipe 130 is located at the welding part 24, thereby improving the intelligence and informatization of welding system 10.

[0092] like Figure 1 As shown, in some embodiments of this application, the welding system 10 further includes a positioning plate 200, and each branch pipe 130 is fixedly connected to the positioning plate 200.

[0093] The positioning plate 200 is a component used for auxiliary positioning, which moves the branch pipes 130 to the welding positions 24. For example, multiple battery cells 100 and conductive connecting pieces 110 are bonded together to form a whole. The positioning plate 200 can be made into a shape that matches the upper end of the whole, so that the positions of the multiple branch pipes 130 on the positioning plate 200 correspond one-to-one with the multiple welding positions 24. In this way, when the positioning plate 200 is fitted onto the upper end of the whole, the ends of the multiple branch pipes 130 are all located at the welding positions 24.

[0094] By setting a positioning plate 200 and fixing multiple branch pipes 130 to the positioning plate 200, the positional relationship between the multiple branch pipes 130 and the part to be welded 24 can be adjusted by moving the positioning plate 200, thereby improving the convenience of adjusting the position of the multiple branch pipes 130.

[0095] In some embodiments of this application, a control valve (not shown in the figure) is provided at the end of each branch pipe 130.

[0096] A control valve is a valve that controls the opening and closing of a branch pipeline 130 and the flow rate. Common control valves include ball valves, butterfly valves, and box valves. Of course, they can also be classified according to the control method, such as manual valves, pneumatic valves, and electric valves, etc., which is not limited in this application.

[0097] The end of branch pipe 130 refers to the end of branch pipe 130 that is close to the conductive connecting piece 110.

[0098] By setting a control valve, it is beneficial to control the flow rate of liquid solder 141 at the end of branch pipe 130 as well as its opening and closing, thereby helping to control the amount of liquid solder 141 in the part to be welded 24, and thus helping to control the welding consistency.

[0099] According to some embodiments of this application, preferably, this application proposes a welding system 10. The welding system 10 includes a container 120, a main delivery pipeline 150, a pump, branch pipelines 130, a positioning plate 200, an image acquisition device 180, and a controller 190. A control valve is provided at the end of the branch pipeline 130 to control the flow and shut-off of liquid solder 141. The pump is located between the main delivery pipeline 150 and the branch pipeline 130, and the branch pipeline 130 is fixed to the positioning plate 200. The image acquisition device 180 acquires image information of the positioning plate 200, the battery cell 100, and the conductive connecting piece 110 in real time. After receiving the image information, the controller 190 determines whether the branch pipeline 130 is located at the welding position 24. During this process, by continuously adjusting the position of the positioning plate 200, the branch pipeline 130 on the positioning plate 200 is moved to the welding position 24 of the battery cell 100 and the conductive connecting piece 110, and the information fed back by the controller 190 confirms that the branch pipeline 130 is located at the welding position 24. Then the pump is started, and the pump draws the liquid solder 141 in the container 120 through the main delivery pipeline 150 and sends it to multiple branch pipelines 130. Finally, the control valve at the end of the branch pipeline 130 is opened to deliver the liquid solder 141 to the part 24 to be welded. After the liquid solder 141 cools down, the welding of the terminals 20 of multiple battery cells 100 to the conductive connecting pieces 110 is completed, which helps to improve the welding efficiency and thus improve the production efficiency of the battery 90.

[0100] Furthermore, if the number of branch pipes 130 is the same as the number of terminals 20, then the terminals 20 and conductive connecting pieces 110 of all battery cells 100 in the battery 90 can be welded at once, thereby further shortening the welding time and improving the production efficiency of the battery 90.

[0101] like Figure 7 As shown, a second aspect of this application proposes a welding method implemented based on the aforementioned welding system 10. The welding method includes:

[0102] Provides multiple battery cells 100 and conductive connecting pieces 110;

[0103] Add liquid solder 141 to container 120;

[0104] Liquid solder 141 is delivered through branch pipe 130 to the terminal post 20 of battery cell 100 and the welding part 24 of conductive connecting piece 110.

[0105] The welding method of this application embodiment is based on the welding system 10. The welding method of this application embodiment simultaneously delivers liquid solder 141 to the welding positions 24 of the battery cells 100 and conductive connecting pieces 110 via multiple branch pipes 130, thereby achieving parallel welding of multiple battery cells 100 and conductive connecting pieces 110. After the terminals 20 of the multiple battery cells 100 of the battery 90 are attached to the conductive connecting pieces 110, the nozzle of each branch pipe simultaneously moves to the welding position 24, i.e., the terminal 20. Because the pipes are elongated, the nozzle size can be designed to match the size of the terminal 20, so multiple branch pipes 130 can be simultaneously located at the welding positions 24. The container 120 contains molten liquid solder 141, which can be molten aluminum alloy, molten aluminum, etc. Liquid solder 141 can flow into the part 24 to be welded along the branch pipe. After the liquid solder 141 solidifies, the pole post 20 of multiple battery cells 100 can be welded to the conductive connecting piece 110 in parallel, which helps to improve welding efficiency and thus improve the production efficiency of battery 90.

[0106] Furthermore, if the number of branch pipes 130 is the same as the number of terminals 20, then the terminals 20 and conductive connecting pieces 110 of all battery cells 100 in the battery 90 can be welded at once, thereby further shortening the welding time and improving the production efficiency of the battery 90.

[0107] In some embodiments of this application, after the step of adding liquid solder 141 to container 120, the welding method further includes:

[0108] Add protective gas to container 120.

[0109] By setting up a protective gas delivery pipeline 160 to deliver protective gas into the container 120, it is beneficial to prevent the liquid solder 141 from being oxidized during the delivery process, thus affecting the welding effect.

[0110] In some embodiments of this application, such as Figure 4 and Figure 5As shown, a cavity 25 is provided on the terminal post 20, and a through hole 26 is provided on the conductive connecting piece 110 opposite to the cavity 25. The step of conveying liquid solder 141 to the terminal post 20 and the welding area 24 of the conductive connecting piece 110 of the battery cell 100 through the branch pipe 130 includes:

[0111] Liquid solder 141 is delivered through branch pipe 130 to cavity 25 on pole post 20 and through hole 26 on conductive connector 110.

[0112] Cavity 25 refers to a structure with a cavity, and through hole 26 allows branch pipe 130 to pass through.

[0113] A cavity 25 is provided on the pole post 20 and a through hole 26 is provided on the conductive connecting piece 110 at a position corresponding to the cavity 25. In this way, the branch pipe 130 can be inserted into the cavity 25 through the through hole 26, which facilitates the positioning of the branch pipe 130. At the same time, the cavity 25 can also accommodate liquid solder 141, which also helps to prevent the liquid solder 141 from overflowing.

[0114] In some embodiments of this application, the welding system 10 further includes an image acquisition device 180 and a controller 190, and the welding method further includes:

[0115] Image acquisition device 180 acquires image information of branch pipe 130, battery cell 100 and conductive connecting piece 110;

[0116] The controller 190 receives image information and determines whether the end of the branch pipe 130 is located at the welding part 24 based on the image information.

[0117] The image acquisition device 180 and the controller 190 facilitate real-time monitoring of whether the branch pipe 130 is located at the welding position 24, thereby improving the intelligence and informatization of the welding system 10.

[0118] In some embodiments of this application, the welding method further includes:

[0119] An exhaust hole 27 communicating with the through hole 26 is provided on the conductive connecting piece 110.

[0120] By setting vent holes, the gas that was originally present in the cavity 25 can be discharged through the vent holes when the liquid solder 141 is injected into the cavity 25, which is beneficial to improving the welding effect.

[0121] According to some embodiments of this application, preferably, this application provides a welding method, comprising:

[0122] Provides multiple battery cells 100 and conductive connecting pieces 110;

[0123] A cavity 25 is provided on the pole post 20, and a through hole 26 is provided on the conductive connecting piece 110 opposite to the cavity 25.

[0124] An exhaust hole 27 communicating with the through hole 26 is provided on the conductive connecting piece 110;

[0125] Add liquid solder 141 to container 120;

[0126] Add protective gas to container 120;

[0127] Image acquisition device 180 acquires image information of branch pipe 130, battery cell 100 and conductive connecting piece 110;

[0128] The controller 190 receives image information and determines whether the end of the branch pipe 130 is located at the welding part 24 based on the image information;

[0129] Liquid solder 141 is delivered through branch pipe 130 to the terminal post 20 of battery cell 100 and the cavity 25 and through hole 26 of conductive connecting piece 110.

[0130] The welding method of this application embodiment is beneficial to realize the parallel welding of the electrode post 20 of multiple battery cells 100 to the conductive connecting piece 110, thereby improving the welding efficiency and thus improving the production efficiency of the battery 90.

[0131] Furthermore, if the number of branch pipes 130 is the same as the number of terminals 20, then the terminals 20 and conductive connecting pieces 110 of all battery cells 100 in the battery 90 can be welded at once, thereby further shortening the welding time and improving the production efficiency of the battery 90.

[0132] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A welding system for welding multiple battery cells to conductive connecting pieces, characterized in that, The welding system comprises: a container for containing liquid solder; a plurality of branch pipes configured to deliver the liquid solder to a welding site between the battery cell and the conductive tab; a delivery main pipe, one end of which is connected to the container, and the other end of which is connected to the plurality of branch pipes; a protective gas delivery pipe connected to the container and configured to deliver protective gas to the container; and a driving device between the delivery main pipe and the plurality of branch pipes, configured to drive the liquid solder in the container to flow through the delivery main pipe and then into the plurality of branch pipes.

2. The welding system of claim 1, wherein, The welding system further comprises an image acquisition device and a controller, the image acquisition device being configured to acquire image information of the branch pipes, the battery cell and the conductive tab; the controller being configured to receive the image information and determine whether the end of the branch pipe is located at the welding site according to the image information.

3. The welding system of claim 1, wherein, The welding system further comprises a positioning plate, and each of the branch pipes is fixedly connected to the positioning plate.

4. The welding system of claim 1, wherein, A control valve is arranged at the end of each of the branch pipes.

5. A welding method, carried out on the basis of a welding system according to any one of claims 1 to 4, characterized in that, The welding method comprises: providing a plurality of battery cells and conductive tabs; adding liquid solder to the container; delivering the liquid solder to the pole of the battery cell and the welding site of the conductive tab through the branch pipes.

6. The welding method of claim 5, wherein, After the step of adding liquid solder to the container, the welding method further comprises: adding protective gas to the container.

7. The welding method of claim 5, wherein, The pole is provided with a cavity, and the conductive tab is provided with a through hole arranged opposite to the cavity; The step of delivering the liquid solder to the pole of the battery cell and the welding site of the conductive tab through the branch pipes comprises: delivering the liquid solder to the cavity on the pole and the through hole on the conductive tab through the branch pipes.

8. The welding method of claim 5, wherein, The welding system further comprises an image acquisition device and a controller; The welding method further comprises: The image acquisition device acquires image information of the branch pipes, the battery cell and the conductive tab; The controller receives the image information and determines whether the end of the branch pipe is located at the welding site according to the image information.

9. The welding method of claim 7, wherein, The welding method further comprises: An exhaust hole is arranged on the conductive tab and communicates with the through hole.

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