Quick welding storage battery busbar structure and manufacturing process

Abstract

The invention provides a rapid welding storage battery busbar structure and a manufacturing process, and relates to the field of lead-acid storage batteries, and the rapid welding storage battery busbar structure comprises a plate group and a nickel-plated steel strip. The nickel-plated steel strip with the conductivity higher than that of lead is adopted as the busbar of the lead-acid storage battery, so that the gravimetric specific energy of the lead-acid storage battery is improved, and the material cost of the lead-acid storage battery is reduced. A hot melting manufacturing mode is replaced by a process that a heating block is attached to a nickel-plated steel strip for indirect heating welding or a movable heat source (oxygen acetylene or laser) scanning welding, so that the production efficiency is improved, the energy consumption is reduced, meanwhile, clean production is realized, and environmental pollution caused by lead smoke, lead dust and lead slag generated by lead melting in the traditional production process is avoided.

Description

Technical Field

[0001] This invention relates to the field of lead-acid batteries, and in particular to a fast-welding battery busbar structure and manufacturing process. Background Technology

[0002] Most lead-acid batteries are 12V batteries, consisting of 6 cells. Each cell has positive and negative plates. The positive and negative plates need to be connected in parallel to weld the tabs together. The current collectors after welding are collectively called busbars. To ensure the service life and high-rate discharge characteristics of lead-acid batteries, the busbar alloy commonly used is mainly lead-tin alloy welded by hot melting. Because lead has a high resistivity, the busbar design often requires more lead to ensure the cross-sectional area.

[0003] Traditional lead-acid battery busbars were initially constructed by welding (fusion-welding) the tabs of the pre-packaged electrode groups together using an oxygen-acetylene hot-melt method, forming a cluster and the current collector that constituted the busbar. This method had several drawbacks: 1. Low efficiency: Casting and welding requires melting lead alloy (>400℃), which consumes a lot of energy and has a long cooling time; 2. Severe pollution: Lead fumes account for more than 60% of the pollution from production, endangering workers' health; 3. High cost: Lead alloy molds wear out quickly, and replacement costs account for 15% of the total production cost; 4. Unstable quality: The rate of poor soldering is as high as 5%, which leads to increased internal resistance and reduced lifespan of the battery.

[0004] Patent document CN102891278A discloses a method for casting and welding lead-acid battery busbars. The method involves placing battery plates perpendicular to the ground along their width, and sequentially inserting tabs located on the same side into the toothed grooves of a busbar fixture. Molten lead from a lead-melting pot is injected into the busbar fixture by a lead supply pump and kept at a constant temperature. Then, heating rods are used to sequentially fuse and weld the tabs together. While this invention replaces manual flame welding, it still involves melting lead in a high-temperature furnace and heating the mold to weld the tabs. The production process cannot solve the environmental pollution caused by lead fumes and dust, nor the generation of lead slag, and therefore does not belong to green production technology.

[0005] Patent documents CN106549183A and CN205752350U both propose using copper or other non-lead metal materials as busbars and connecting them to the tabs via mechanical fixing. Patent document CN110767869A also proposes a similar solderless solution. This significantly improves production efficiency and reduces the energy consumption and environmental pollution associated with traditional welding. However, in actual production, due to tab oxidation and misalignment, the actual production efficiency cannot meet expectations. Furthermore, because of the poor reliability of the mechanical connection and high interface resistance, the battery cannot support high-current charging and discharging, affecting normal use, and therefore it has not been used in production. Summary of the Invention

[0006] The purpose of this invention is to provide a rapid welding structure and manufacturing process for battery busbars. It uses nickel-plated steel strips with a conductivity far exceeding that of lead as the busbar material. The tabs are mechanically bonded together, and welding is performed using indirect heating with heating blocks or scanning welding with a moving heat source (oxygen-acetylene or laser). Compared to the traditional lead-cast busbar welding process, this not only significantly improves production efficiency and reduces energy consumption, but also achieves clean production, avoiding environmental pollution caused by lead fumes, lead dust, and lead slag generated during lead melting in traditional production processes.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a manufacturing process for a rapidly welded battery busbar, comprising the following steps: S1. Provide an electrode group, a nickel-plated steel strip, and a battery compartment, wherein the electrode group has tabs; install the electrode group in the battery compartment, and assemble the nickel-plated steel strip with the tabs such that the nickel-plated steel strip wraps around the top of the tabs; S2. Indirect heating is achieved by attaching a heating block to the nickel-plated steel strip, thereby raising the temperature of the nickel-plated steel strip and fusing it together with the electrode tab after contact; or, a mobile heat source is used to scan and heat the nickel-plated steel strip, thereby fusing it together with the electrode tab after contact. S3. Take the electrode group and nickel-plated steel strip obtained in step S2 out of the battery case, and cut off the excess part of the nickel-plated steel strip to form a busbar; S4. Install the electrode group with busbars obtained in step S3 into the battery case, seal it with glue, and then cover it. S5. After sealing, cut the corresponding position on the top of the battery cover to expose the positive and negative terminals of the battery.

[0008] In one embodiment, the mobile heat source is an oxy-acetylene torch, which generates an oxy-acetylene flame that scans and heats the nickel-plated steel strip, causing the nickel-plated steel strip to come into contact with the electrode tab and fuse together.

[0009] In one embodiment, the flame temperature of the oxyacetylene flame is controlled at 500–2000°C, and the scanning speed is 0.01–0.2 m / s.

[0010] In one embodiment, the mobile heat source is a laser, which generates laser light to scan and heat the nickel-plated steel strip, causing the nickel-plated steel strip to come into contact with the tab and fuse together.

[0011] In one embodiment, the laser power is 1-8 kW and the scanning speed is 0.01-0.2 m / s.

[0012] In one embodiment, before assembling the nickel-plated steel strip with the electrode tab in step S1, the method further includes cutting and shaping the electrode tab.

[0013] In one embodiment, step S1 involves assembling the nickel-plated steel strip with the electrode tab, such that the nickel-plated steel strip wraps around the top of the electrode tab, and also includes using mechanical pressure to make the nickel-plated steel strip adhere to the electrode tab.

[0014] The present invention also provides a fast-welding battery bus structure, characterized in that the battery bus structure is manufactured using the fast-welding battery bus manufacturing process described in any of the preceding claims.

[0015] In one embodiment, the nickel-plated steel strip is U-shaped and wraps around the top of the electrode tab.

[0016] In one embodiment, the thickness of the nickel-plated steel strip is 0.02 to 2 mm.

[0017] The technical solution provided by this invention has the following technical effects: This invention provides a rapid welding structure and manufacturing process for a battery busbar, relating to the field of lead-acid batteries, including electrode groups and nickel-plated steel strips. This invention uses nickel-plated steel strips with higher conductivity than lead as the busbars for lead-acid batteries, improving the specific energy of lead-acid batteries by weight and reducing material costs. The invention replaces the traditional hot-melt manufacturing method with a process using heating blocks bonded to the nickel-plated steel strip for indirect heating welding or scanning welding with a mobile heat source (oxy-acetylene or laser), improving production efficiency, reducing energy consumption, and achieving clean production, avoiding environmental pollution caused by lead fumes, lead dust, and lead slag generated during lead melting in traditional production processes. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the process flow described in an embodiment of the present invention; Figure 2 This is a perspective view of a semi-finished battery formed by welding and cutting to create a series busbar between individual cells, as described in an embodiment of the present invention. Figure 3 This is a schematic diagram of the assembly of the nickel-plated steel strip and the electrode group tabs according to an embodiment of the present invention; Figure 4 This is a three-dimensional schematic diagram of the indirect heating welding scheme using heating blocks as employed in an embodiment of the present invention; Figure 5This is a schematic diagram of the finished product of the rapid welding busbar battery according to an embodiment of the present invention; Figure 6 This is a three-dimensional schematic diagram of the oxy-acetylene flame or laser scanning welding scheme used in the embodiments of the present invention. Detailed Implementation

[0019] To further illustrate the various embodiments, the present invention provides accompanying drawings. These drawings are part of the disclosure of the present invention and are mainly used to illustrate the embodiments, and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these drawings, those skilled in the art should be able to understand other possible implementations and the advantages of the present invention. Components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0020] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0021] Example 1 Reference Figures 1-6 This embodiment provides a fast-welding battery busbar structure, including electrode groups 10, a positive terminal 20, a negative terminal 30, and a busbar 40. Each electrode group 10 has a positive tab 11, a negative tab 12, and a separator 13. Multiple electrode groups 10 can be provided, as shown in the reference. Figure 1 In this embodiment, six pole groups 10 are provided. However, in some other embodiments, more or fewer pole groups 10 may be provided; for example, at least one pole group 10 may be provided.

[0022] Reference Figure 2 , Figure 5 ,in Figure 5 The finished battery 1 is shown. The battery 1 also includes a battery compartment 50. The battery compartment 50 can be used to install the pole group 10.

[0023] Reference Figures 2-5 Key reference Figure 2 , Figure 3 The nickel-plated steel strip 4 is connected to the positive electrode tab 11 and the negative electrode tab 12 by welding or other means, and then cut to form a busbar 40.

[0024] At 20℃, depending on the substrate and nickel plating thickness, the resistivity of nickel-plated steel strip is generally 0.7–10 μΩ·m, far lower than the resistivity of lead (20.65 μΩ·cm). This means the conductivity of nickel-plated steel strip 4 is significantly higher than that of lead. Using nickel-plated steel strip 4, with its higher conductivity than lead, as the busbar of a lead-acid battery can improve the specific energy of the lead-acid battery and reduce its material cost. Simultaneously, nickel-plated steel strip has excellent weldability and can form good weld strength with lead tabs.

[0025] Reference Figures 2-5 Key reference Figure 4 The connection between the nickel-plated steel strip 4 and the positive electrode tab 11 and negative electrode tab 12 can be achieved by indirect heating welding using a heating block 5. Before welding, the nickel-plated steel strip 4 can be mechanically pressed against the positive electrode tab 11 and negative electrode tab 12 of the electrode group 10. Welding is achieved by indirect heating using the heating block 5 against the nickel-plated steel strip 4, with the temperature controlled between 300 and 1000°C. After the weld is secure, the busbar 40 is formed by cutting and sealed with adhesive. Adhesive sealing provides oxidation and corrosion resistance. Adhesives include, but are not limited to, epoxy resin adhesive and hot melt adhesive.

[0026] Reference Figure 2 , Figure 3 The nickel-plated steel strip 4 has a concave cross-section and wraps around the top of the electrode tabs 11 and 12; however, it is not limited to this. In some other embodiments, the nickel-plated steel strip 4 can also be in the form of a flat sheet. The flat sheet-shaped nickel-plated steel strip 4 can be bent to wrap around the top of the electrode tabs 11 and 12. The thickness of the nickel-plated steel strip 4 is 0.02-2 mm. In this embodiment, the concave cross-section of the nickel-plated steel strip 4 provides a more stable wrap around the electrode tabs.

[0027] Of course, as an improved embodiment, such as Figure 6 As shown, a mobile heat source can also be used for scanning welding to connect the nickel-plated steel strip 4 to the tabs 11 and 12 of the electrode group 10. The mobile heat source includes, but is not limited to, an oxygen-acetylene flame or a laser.

[0028] Reference Figure 6 When using an oxy-acetylene torch 6 to scan and heat the nickel-plated steel strip 4, the temperature is controlled between 500 and 2000°C, and the scanning speed is between 0.01 and 0.2 m / s.

[0029] Continue to refer to Figure 6 When using laser 7 to scan and heat the nickel-plated steel strip 4 for welding, its power is 1 to 8 kW and the scanning speed is 0.01 to 0.2 m / s.

[0030] This invention replaces the hot-melt manufacturing method with a process of indirect heating welding of heating block 5 to nickel-plated steel strip 4 or scanning welding with a mobile heat source (oxygen-acetylene flame or laser). The table below shows a comparison of various parameters between the traditional casting and welding process and the process of this invention. This invention can improve production efficiency, reduce energy consumption, and achieve clean production, avoiding environmental pollution caused by lead fumes, lead dust, and lead slag generated during lead melting in the traditional production process.

[0031]

[0032] Example 2 Reference Figures 1-6 Key reference Figure 1This embodiment provides a manufacturing process for a rapidly welded battery busbar, characterized by the following steps: S1. Provide an electrode group 10, a nickel-plated steel strip 4, and a battery compartment 50. The electrode group 10 has tabs 11 and 12. Install the electrode group 10 in the battery compartment 50 and assemble the nickel-plated steel strip 4 with the tabs 11 and 12 such that the nickel-plated steel strip 4 wraps around the top of the tabs 11 and 12. S2. Indirect heating is achieved by attaching a heating block 5 to the nickel-plated steel strip 4, which raises the temperature of the nickel-plated steel strip 4 and fuses it together with the tabs 11 and 12 after contact; or, a mobile heat source is used to scan and heat the nickel-plated steel strip 4, which fuses it together with the tabs 11 and 12 after contact. S3. Take the electrode group 10 and nickel-plated steel strip 4 obtained in step S2 out of the battery compartment 50, and cut off the excess part of the nickel-plated steel strip 4 to form busbar 40. S4. Install the electrode group 10 connected to the busbar 40 obtained in step S3 into the battery compartment 50, seal it with glue, and then cover it. S5. After sealing, cut the corresponding position on the top of the battery cover to expose the positive and negative terminals of the battery.

[0033] Reference Figure 6 In step S2, the mobile heat source is an oxygen-acetylene torch 6. The oxygen-acetylene torch 6 generates an oxygen-acetylene flame that scans and heats the nickel-plated steel strip 4, so that the nickel-plated steel strip 4 comes into contact with the tabs 11 and 12 and is fused together. The flame temperature is controlled at 500 to 2000°C and the scanning speed is 0.01 to 0.2 m / s.

[0034] Continue to refer to Figure 6 In another embodiment, the mobile heat source is a laser 7, which generates a laser to scan and heat the nickel-plated steel strip 4 for welding. The laser power is 1 to 8 kW, so that the nickel-plated steel strip 4 comes into contact with the tabs 11 and 12 and is fused together. The scanning speed is 0.01 to 0.2 m / s.

[0035] Furthermore, in step S1, before assembling the nickel-plated steel strip 4 with the electrode tab, the electrode tab is further cut and shaped to make its shape more compatible with the nickel-plated steel strip 4.

[0036] Further, in step S1, the nickel-plated steel strip 4 is assembled with the tabs 11 and 12, such that the nickel-plated steel strip 4 wraps around the top of the tabs 11 and 12. The assembly also includes using mechanical pressure to make the nickel-plated steel strip 4 adhere to the tabs 11 and 12.

[0037] Example 3 Reference Figures 1-6 Key reference Figure 6 In this embodiment, an oxy-acetylene torch 6 is used to generate an oxy-acetylene flame that scans and heats the nickel-plated steel strip 4, causing the nickel-plated steel strip 4 to come into contact with and fuse together with the tabs 11 and 12. Nickel-steel strip dimensions: 9mm wide × 0.8mm thick, preload pressure 10MPa.

[0038] Spray gun parameters: flame temperature 700℃, moving speed 8cm / s, height from steel strip 10mm.

[0039] Results: Welding time was 5 seconds (traditional process requires 25 seconds), and lead fume concentration was 0.5 mg / m³ (cast welding concentration was 10 mg / m³).

[0040] Example 4 Reference Figures 1-6 Key reference Figure 6 In this embodiment, a laser 7 is used to generate a laser to scan and heat the nickel-plated steel strip 4, so that the nickel-plated steel strip 4 comes into contact with the tabs 11 and 12 and is fused together. Nickel steel strip dimensions: 8mm wide × 1mm thick, preload pressure 8MPa.

[0041] Fiber laser 7: wavelength 1064nm, power 3kW, spot diameter 0.5mm.

[0042] Results: The heat-affected zone depth was only 0.2 mm, the tabs showed no thermal deformation, and the energy consumption was 0.3 kWh (compared to 1.8 kWh for cast welding).

[0043] This invention uses a nickel-plated steel strip 4 with higher conductivity than lead as the busbar of a lead-acid battery, which improves the specific energy of the lead-acid battery by weight and reduces the material cost. The process of indirectly heating and welding the heating block 5 to the nickel-plated steel strip 4, or scanning welding with a mobile heat source (oxy-acetylene or laser), replaces the hot-melt manufacturing method, improving production efficiency, reducing energy consumption, and achieving clean production. This avoids the environmental pollution caused by lead fumes, lead dust, and lead slag generated during lead melting in traditional production processes.

[0044] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A manufacturing process for a rapidly welded battery busbar, characterized in that, Includes the following steps: S1. Provide an electrode group, a nickel-plated steel strip, and a battery compartment, wherein the electrode group has tabs; install the electrode group in the battery compartment, and assemble the nickel-plated steel strip with the tabs such that the nickel-plated steel strip wraps around the top of the tabs; S2. Indirect heating is achieved by attaching a heating block to the nickel-plated steel strip, thereby raising the temperature of the nickel-plated steel strip and fusing it together with the electrode tab after contact; or, a mobile heat source is used to scan and heat the nickel-plated steel strip, thereby fusing it together with the electrode tab after contact. S3. Take the electrode group and nickel-plated steel strip obtained in step S2 out of the battery case, and cut off the excess part of the nickel-plated steel strip to form a busbar; S4. Install the electrode group with busbars obtained in step S3 into the battery case, seal it with glue, and then cover it. S5. After sealing, cut the corresponding position on the top of the battery cover to expose the positive and negative terminals of the battery.

2. The manufacturing process according to claim 1, characterized in that: The mobile heat source is an oxygen-acetylene torch, which generates an oxygen-acetylene flame that scans and heats the nickel-plated steel strip, causing the nickel-plated steel strip to come into contact with the electrode tab and fuse together.

3. The manufacturing process according to claim 2, characterized in that: The flame temperature of the oxyacetylene flame is controlled at 500–2000℃, and the scanning speed is 0.01–0.2 m / s.

4. The manufacturing process according to claim 1, characterized in that: The mobile heat source is a laser, which generates laser light to scan and heat the nickel-plated steel strip, causing the nickel-plated steel strip to come into contact with the electrode tab and fuse together.

5. The manufacturing process according to claim 4, characterized in that: The laser has a power of 1 to 8 kW and a scanning speed of 0.01 to 0.2 m / s.

6. The manufacturing process according to claim 1, characterized in that: In step S1, before assembling the nickel-plated steel strip with the electrode tab, the method further includes cutting and shaping the electrode tab.

7. The manufacturing process according to claim 1, characterized in that: In step S1, the nickel-plated steel strip is assembled with the electrode tab so that the nickel-plated steel strip wraps around the top of the electrode tab. The assembly also includes using mechanical pressure to make the nickel-plated steel strip fit against the electrode tab.

8. A rapid-welding battery busbar structure, characterized in that, The battery bus structure is manufactured using the rapid welding battery bus manufacturing process described in any one of claims 1-7.

9. The battery busbar structure according to claim 8, characterized in that: The nickel-plated steel strip is U-shaped and wraps around the top of the electrode tab.

10. The battery busbar structure according to claim 8, characterized in that: The thickness of the nickel-plated steel strip is 0.02 to 2 mm.

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