Cooling device for laser welding of battery tab and cover plate

Abstract

The application discloses a cooling device for laser welding of a battery connecting sheet and a cover plate, and a positioning mechanism, which comprises a plurality of support columns arranged at intervals on a base and a positioning seat and arranged on the base for supporting the positioning seat; a positioning groove for positioning the cover plate is formed on the positioning seat, and a cooling hole corresponding to the bottom surface of the pole is formed on the bottom wall of the positioning groove; at least one heat transfer block corresponding to the cooling hole is arranged between the base and the positioning seat; a cooling cavity for containing a cooling medium is formed in the heat transfer block, and the top surface is used for contacting the bottom surface of the pole to transfer the heat of the pole to the cooling medium; a cooling mechanism comprises a temperature control unit for controlling the temperature of the cooling medium, a conveying pipe and a recovery pipe, the conveying pipe is connected to the inlet of the cooling cavity, the recovery pipe is connected to the outlet of the cooling cavity, and a closed loop is formed for conveying the cooling medium to the cooling cavity and recovering. The application has the beneficial effect that the heat dissipation efficiency of the pole during laser welding can be improved.

Description

Technical Field

[0001] This invention relates to a cooling device for laser welding of battery connectors and cover plates, and is an improved design of the cooling structure for laser welding of cover plates. Background Technology

[0002] During the production and assembly of power batteries, the battery cover plate needs to be placed on a welding platform for laser welding. The battery cover plate has positive and negative terminals for connecting to the positive and negative terminals of the battery cells, respectively. During welding, laser welding equipment is used to weld the battery cover plate and the cell terminals together. The positive and negative terminals of the battery cover plate have sealing rings (made of rubber). The melting point of the sealing rings (generally less than 300℃) is much lower than the welding temperature (generally greater than 1000℃). During laser welding, the heat from the terminals rises rapidly and is transferred to the sealing rings. At this high temperature, part of the sealing ring may melt, causing it to not be properly sealed and resulting in "air leakage," affecting the safety of the power battery. Therefore, heat dissipation is necessary for the terminals during laser welding to ensure battery safety.

[0003] In existing technologies, air-cooled systems utilize air as a medium to dissipate heat from the electrode posts, resulting in low installation costs and high safety, and are therefore widely used. However, air-cooling dissipates heat from the entire cover plate, which is insufficient for dissipating heat from the electrode posts themselves. It requires prolonged continuous air cooling to achieve the desired cooling effect, leading to significant energy waste. Furthermore, air-cooling is greatly affected by environmental factors; high-temperature environments significantly impact its cooling efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a cooling device for laser welding of battery connectors and cover plates, which can improve the heat dissipation efficiency of the electrode during laser welding.

[0005] This invention is achieved through the following technical solution.

[0006] A cooling device for laser welding of battery connectors and cover plates includes: The positioning mechanism includes a base and a positioning seat spaced apart, and a plurality of support columns on the base for supporting the positioning seat; a positioning groove for positioning a cover plate is formed on the positioning seat, and a cooling hole is formed on the bottom wall of the positioning groove corresponding to the bottom surface of the pole column. At least one heat transfer block corresponding to the cooling hole is disposed between the base and the positioning seat; a cooling chamber for containing the cooling medium is formed in the heat transfer block, and the top surface is used to contact the bottom surface of the electrode to transfer the heat of the electrode to the cooling medium. The cooling mechanism includes a temperature control unit for controlling the temperature of the cooling medium, a delivery pipe, and a recovery pipe. The delivery pipe is connected to the inlet of the cooling chamber, and the recovery pipe is connected to the outlet of the cooling chamber, forming a closed loop for delivering and recovering the cooling medium to the cooling chamber.

[0007] As a further improvement of the present invention, it also includes an elastic support member for vertically supporting the heat transfer block and providing a rebound force to lift the heat transfer block; when the heat transfer block is in a balanced state, the top surface of the heat transfer block is always at a higher position relative to the bottom surface of the pole post positioned on the positioning groove.

[0008] As a further improvement of the present invention, the base is provided with a guide mechanism for limiting the movement trajectory of the heat transfer block, and the guide structure has at least a guide member that cooperates with the heat transfer block to guide the heat transfer block to move vertically.

[0009] As a further improvement of the present invention, the guide structure includes a hollow guide seat and a plurality of circumferentially spaced guide members. The guide seat has an opening for the heat transfer block to enter or move out. The guide members are rotatably connected to the guide seat via a connecting shaft. The heat transfer block has a rolling plane for vertically rolling engagement with the guide members.

[0010] As a further improvement of the present invention, the inner wall of the guide seat is provided with a mounting groove corresponding to each of the guide members, and the connecting shaft is connected to the groove wall of the mounting groove.

[0011] As a further improvement of the present invention, a plurality of the guide members are evenly spaced along the circumference of the heat transfer block.

[0012] As a further improvement of the present invention, the elastic support is configured as a spring, and a limiting rod for limiting the lateral position of the spring is provided on the inner bottom wall of the guide seat, and the spring is sleeved on the limiting rod; a support seat for supporting the spring is provided on the limiting rod.

[0013] As a further improvement of the present invention, the inlet and outlet of the cooling chamber are formed on the bottom surface of the heat transfer block, and the bottom of the guide seat is provided with a through hole that allows the delivery pipe and the recovery pipe to pass through.

[0014] As a further improvement of the present invention, the inlet is connected to the cooling cavity through a first channel, and the outlet is connected to the cooling chamber through a second channel; and the cross-sectional area of ​​the first channel is larger than the cross-sectional area of ​​the second channel.

[0015] As a further improvement of the invention, the cooling chamber is formed at the top position within the heat transfer block.

[0016] The beneficial effects of this invention are: 1. By utilizing the positioning groove and cooling hole, the heat transfer block can make precise contact with one end face of the electrode post. The heat generated by laser welding is then quickly transferred to the cooling medium in the cooling chamber through the heat transfer block, which can quickly reduce the temperature of the electrode post. On the one hand, this can effectively prevent the sealing material around the electrode post from melting due to heat. On the other hand, compared with air cooling, it significantly reduces the heat dissipation time of the electrode post, reduces waiting time, and improves the efficiency of welding operations. Furthermore, the delivery pipe, recovery pipe and cooling chamber of the cooling mechanism form a closed-loop cooling system to achieve continuous circulation of the cooling medium. The temperature control mechanism continuously cools the cooling medium, so that the cooling medium input into the cooling chamber can maintain a low and stable temperature, achieving continuous and efficient heat dissipation of the electrode post.

[0017] 2. When the heat transfer block and the electrode are always in close contact, the electrode will transfer the mechanical stress generated during laser welding to the heat transfer block. The elastic support can absorb the mechanical stress generated by the thermal expansion of the electrode. On the one hand, it keeps the heat transfer block and the electrode in close contact, ensuring efficient and stable heat transfer during welding. On the other hand, it reduces the risk of increased gap between the electrode and the battery connecting piece after the electrode expands due to heat, reducing the risk of incomplete welding and discontinuous welds during welding, and helping to improve welding quality. Attached Figure Description

[0018] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings to aid in understanding the objectives and advantages of the present invention, wherein: Figure 1 This is a top-down view of the structure of the cooling device and cover plate of the present invention. Figure 2 A schematic diagram of the structure in which the positioning mechanism and the heat transfer block cooperate; Figure 3 This is a structural schematic diagram of the cover plate from one perspective. Figure 4 This is a structural schematic diagram of the cover plate from another perspective; Figure 5 This is a vertical sectional view showing the heat transfer block cooperating with the guide mechanism; Figure 6 This is a vertical sectional view of the heat transfer block; Figure 7 This is a schematic diagram of the guiding mechanism; Figure 8 This is a bottom view of the base; Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0020] The directional terms such as up, down, left, right, front, back, front, back, top, and bottom mentioned or possibly used in this specification are defined relative to the construction shown in the accompanying drawings. The terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively. These are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive.

[0021] This embodiment provides a cooling device for laser welding of battery connectors and cover plates, used to cool the electrode post m1 during laser welding. (Refer to...) Figure 1-8 It includes a positioning mechanism 1, a heat transfer block 2 and a cooling mechanism 3. The positioning mechanism 1 includes a base 11 and a positioning seat 12 spaced apart, and a plurality of support columns on the base 11 for supporting the positioning seat 12. The positioning seat 12 forms a positioning groove 14 for positioning the cover plate m, and the positioning groove 14 is provided with a cooling hole 15 corresponding to the pole column m1 on the cover plate m.

[0022] The heat transfer block 2 is located between the base 11 and the positioning seat 12 and corresponds to the position of the cooling hole 15. The interior of the heat transfer block 2 forms a cooling chamber 21 for containing the cooling medium. The top surface is used to contact the bottom surface of the electrode m1 to transfer the heat of the electrode m1 to the cooling medium. The number of heat transfer blocks 2 can correspond one-to-one with the cooling hole 15, or it can be set to one.

[0023] The cooling mechanism 3 includes a temperature control unit for controlling the temperature of the cooling medium, a delivery pipe 31 and a recovery pipe 32. The delivery pipe 31 is connected to the inlet 22 of the cooling chamber 21, and the recovery pipe 32 is connected to the outlet 23 of the cooling chamber 21, forming a closed loop for delivering and recovering the cooling medium to the cooling chamber 21.

[0024] In this embodiment, the positioning groove 14 and the cooling hole 15 are used to make precise contact between the heat transfer block 2 and one end face of the pole m1. The heat generated by laser welding is then quickly transferred to the cooling medium in the cooling chamber through the heat transfer block, which can quickly reduce the temperature of the pole m1. On the one hand, it can effectively prevent the sealing material around the pole m1 from melting due to heat. On the other hand, compared with air cooling, it significantly reduces the heat dissipation time of the pole and improves the efficiency of welding operation. Furthermore, the delivery pipe 31, the recovery pipe 32 and the cooling chamber 21 of the cooling mechanism 3 form a closed-loop cooling system to realize the continuous circulation of the cooling medium. The temperature control mechanism is used to continuously cool the cooling medium, so that the cooling medium input into the cooling chamber 21 can maintain a low temperature and stability, and achieve continuous and efficient heat dissipation of the pole m1.

[0025] Furthermore, compared to the air-cooling method in existing technologies, its heat dissipation efficiency is not affected by environmental factors.

[0026] It should be noted that, referring to Figure 1 , Figure 3 and Figure 4 In this device, the cover plate m includes a cover plate body m2 and two positive and negative poles m1 embedded in the cover plate body m2. The end face of the pole m1 on the side away from the battery connecting piece protrudes from the surface of the cover plate body m2. Therefore, when the cover plate m is positioned on the positioning seat 12, the heat transfer block 2 is in direct contact with the bottom surface of the pole m1, and the top surface of the pole m1 is welded to the battery connecting piece.

[0027] In this embodiment, to ensure efficient heat transfer of the welding heat on the electrode m1, the heat transfer block 2 is made of materials with high thermal conductivity, such as copper, aluminum, and silver. In practice, copper is preferred for preparing the heat transfer block 2 because it is low in cost and easy to process.

[0028] Reference Figure 5 The cooling device in this embodiment also includes an elastic support 5. The elastic support 5 is made of elastic material and can deform under external force and return to its original shape after the external force is removed. The elastic support 5 is located below the heat transfer block 2 and is used to vertically support the heat transfer block 2 and provide a rebound force to lift the heat transfer block 2. When the heat transfer block 2 is in a balanced state, the top surface of the heat transfer block 2 is always at a higher position relative to the bottom surface of the pole m1 positioned on the positioning groove 14.

[0029] The aforementioned equilibrium state refers to the state where the elastic force generated by the deformation of the elastic support 5 is equal in magnitude and opposite in direction to the weight of the heat transfer block 2, thus keeping the position of the heat transfer block 2 stable. Furthermore, since the top surface of the heat transfer block 2 is always at a higher position relative to the bottom surface of the pole m1 positioned on the positioning groove 14, when the pole is positioned on the positioning groove 14, the bottom surface of the pole will definitely be able to contact the top surface of the heat transfer block 2, and drive the heat transfer block 2 to move downward, causing the elastic support 5 to deform further. At this time, under the upward elastic force applied by the elastic support 5, the heat transfer block 2 is tightly attached to the bottom surface of the pole m1, maintaining efficient heat transfer during welding.

[0030] Since the temperature during laser welding typically reaches over 1000℃, and the electrode post m1 on the cover plate m is generally made of metal materials such as copper or aluminum, the electrode post m1 is prone to expansion when heated. During welding, to ensure welding quality and weld appearance, the battery connecting piece and the electrode post m1 need to be in close contact. However, the mechanical stress generated by the expansion of the electrode post m1 can easily cause displacement of the battery connecting piece, leading to an increased gap between the battery connecting piece and the electrode post m1, resulting in incomplete welds or discontinuous welds, thus affecting welding quality. In this embodiment, with the heat transfer block 2 and the electrode post m1 always in close contact, the electrode post m1 transfers the mechanical stress generated during laser welding to the heat transfer block 2. The elastic support 5 absorbs the mechanical stress generated by the thermal expansion of the electrode, ensuring that the heat transfer block 2 and the electrode remain in close contact, maintaining efficient and stable heat transfer during welding. Furthermore, it reduces the risk of an increased gap between the electrode and the battery connecting piece after thermal expansion, reducing the risk of incomplete welds and discontinuous welds, and thus improving welding quality.

[0031] In this embodiment, a guiding mechanism 4 is provided on the base 11 to limit the movement trajectory of the heat transfer block 2. The guiding structure has at least one guide member 41 that guides the heat transfer block 2 to move vertically. Specifically, the guiding structure includes a hollow guide seat 42 and multiple guide members 41 spaced circumferentially. The top of the guide seat 42 has an opening that allows the heat transfer block 2 to move into or out of the guide seat 42. The guide seat 42 can be bolted to the base 11. The guide members 41 are rotatably connected to the guide seat 42 via a connecting shaft 43. The heat transfer block 2 has a rolling surface for rolling vertically with the guide members 41. Under the rolling engagement, the friction force on the heat transfer block 2 is small, which helps to maintain the movement stability of the heat transfer block 2. It should be noted that the guide member 41 here is a roller, which engages with the rolling surface on the surface of the heat transfer block 2. Multiple guide members 41 are used to limit the movement trajectory of the heat transfer block 2.

[0032] In other embodiments, the guide member 41 and the heat transfer block 2 can also be guided to move by sliding in a vertical direction.

[0033] In this embodiment, the inner wall of the guide seat 42 is provided with a mounting groove 44 corresponding to each guide member 41. The two ends of the connecting shaft 43 are connected to the groove wall of the mounting groove 44. The guide member 41 can be installed on the connecting shaft 43 through a bushing. The mounting groove 44 facilitates the installation of the guide member 41. Furthermore, multiple guide members 41 are evenly spaced along the circumference of the heat transfer block 2, so that the heat transfer block 2 is subjected to balanced force, preventing deformation or damage caused by single-point stress concentration, which is suitable for high-frequency welding scenarios.

[0034] In this embodiment, the elastic support 5 is preferably a compressible spring. The inner bottom wall of the guide seat 42 is provided with a limiting rod 6 for limiting the lateral position of the spring. The spring is sleeved on the limiting rod 6, and the limiting rod 6 is provided with a support seat 7 for supporting the spring. One end of the spring abuts against the support seat 7, and the other end abuts against the bottom of the heat transfer block 2 to support the heat transfer block 2. Under this structure, there is no rigid connection between the heat transfer block 2 and the spring, and elastic support 5 with different coefficients can be configured according to actual needs.

[0035] In this embodiment, the inlet 22 and outlet 23 of the cooling chamber 21 are formed on the bottom surface of the heat transfer block 2. The bottom of the guide seat 42 has a through hole 45 that allows the conveying pipe 31 and the recovery pipe 32 to pass through. When the heat transfer block 2 moves vertically, the conveying pipe 31 and the recovery pipe 32 will not interfere with it, thus avoiding pipe entanglement or compression and reducing the failure rate. Furthermore, referring to… Figure 7 An clearance hole is provided on the base 11 at the position corresponding to the guide seat 42, so that the conveying pipe 31 and the recycling pipe 32 can enter the through hole 45 through the clearance hole, and sufficient gap is left between the bottom of the base 11 and the worktable.

[0036] In this embodiment, the inlet 22 is connected to the cooling chamber 21 through the first channel 24, and the outlet 23 is connected to the cooling chamber 21 through the second channel 25. When the cooling medium circulates, the cooling medium in the cooling chamber 21 flows in through the first channel 24 and flows out through the second channel 25 to the recovery pipe 32, thereby realizing the circulation of the cooling medium. Furthermore, the cross-sectional area of ​​the first channel 24 is larger than that of the second channel 25, so that the speed at which the cooling medium enters the cooling chamber 21 is greater than the speed at which it flows out of the cooling chamber 21. Therefore, when the cooling medium circulates, the flow rate of the cooling medium entering the cooling chamber 21 is always greater than the flow rate out of the cooling chamber 21, which helps to improve the heat absorption efficiency.

[0037] It should be noted that, in this embodiment, at least one inlet 22 and outlet 23 should be provided to ensure the normal circulation of the cooling medium.

[0038] Furthermore, in some other embodiments, reference is made to Figure 6To improve welding cooling efficiency, multiple outlets 23 can be provided on the heat transfer block 2, and the first channel 24 is connected to the middle of the cooling chamber 21, while the second channel 25 is connected to the edge of the cooling chamber 21. Therefore, during the process of the cooling medium flowing into the interior of the cooling chamber 21 from the first channel 24 and out through the second channel 25, the flow path of the cooling medium within the cooling chamber 21 can be reduced, thereby accelerating the circulation speed of the cooling medium within the cooling chamber 21 and improving cooling efficiency. Furthermore, the cooling chamber 21 is formed at the top of the heat transfer block 2, and its position is directly close to the electrode m1, maximizing the utilization of heat conduction principles and improving cooling efficiency.

[0039] The cooling mechanism 3 in this embodiment can be a water chiller or a liquid chiller, which can store the cooling medium and control the temperature of the cooling medium through a temperature control unit, so that the cooling medium entering the cooling chamber 21 can always maintain a stable temperature. It should be noted that the cooling medium here can be deionized water or other liquid cooling media.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention 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 of the technical features. Such 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 the present invention.

Claims

1. A cooling device for laser welding of battery connectors and cover plates, characterized in that, include: The positioning mechanism (1) includes a base (11) and a positioning seat (12) spaced apart, and a plurality of support columns provided on the base (11) for supporting the positioning seat (12); a positioning groove (14) for positioning the cover plate (m) is formed on the positioning seat (12), and a cooling hole (15) is formed on the bottom wall of the positioning groove (14) corresponding to the pole post (m1). At least one heat transfer block (2) corresponding to the cooling hole (15) is provided between the base (11) and the positioning seat (12). A cooling chamber (21) for containing the cooling medium is formed in the heat transfer block (2). The top surface is used to contact the bottom surface of the pole (m1) to transfer the heat of the pole (m1) to the cooling medium. The cooling mechanism (3) includes a temperature control unit for controlling the temperature of the cooling medium, a delivery pipe (31) and a recovery pipe (32). The delivery pipe (31) is connected to the inlet (22) of the cooling chamber (21), and the recovery pipe (32) is connected to the outlet (23) of the cooling chamber (21), forming a closed loop for delivering and recovering the cooling medium to the cooling chamber (21). It also includes an elastic support (5) for vertically supporting the heat transfer block (2) and providing a rebound force to lift the heat transfer block (2); when the heat transfer block (2) is in a balanced state, the top surface of the heat transfer block (2) is always at a high position relative to the bottom surface of the pole (m1) positioned on the positioning groove (14); the base (11) is provided with a guide mechanism (4) for limiting the movement trajectory of the heat transfer block (2), the guide mechanism (4) has at least a guide member (41) that guides the heat transfer block (2) to move vertically; the guide mechanism (4) includes a hollow guide seat (42) and a plurality of circumferentially spaced guide members (41), the guide seat (42) has an opening for the heat transfer block (2) to enter or move out, the guide member (41) is rotatably connected to the guide seat (42) through a connecting shaft (43), and the heat transfer block (2) has a rolling plane for rolling with the guide member (41) vertically.

2. The cooling device for laser welding of battery connecting pieces and cover plates according to claim 1, characterized in that, The inner wall of the guide seat (42) is provided with a mounting groove (44) corresponding to each guide member (41), and the connecting shaft (43) is connected to the groove wall of the mounting groove (44).

3. The cooling device for laser welding of battery connecting pieces and cover plates according to claim 1, characterized in that, Multiple guide members (41) are evenly spaced along the circumference of the heat transfer block (2).

4. The cooling device for laser welding of battery connecting pieces and cover plates according to claim 1, characterized in that, The elastic support (5) is a spring, and the inner bottom wall of the guide seat (42) is provided with a limiting rod (6) for limiting the lateral position of the spring. The spring is sleeved on the limiting rod (6). The limiting rod (6) is provided with a support seat (7) for supporting the spring.

5. A cooling device for laser welding of battery connecting pieces and cover plates according to claim 2, characterized in that, The inlet (22) and outlet (23) of the cooling chamber (21) are formed on the bottom surface of the heat transfer block (2), and the bottom of the guide seat (42) is provided with a through hole (45) that allows the delivery pipe (31) and the recovery pipe (32) to pass through.

6. The cooling device for laser welding of battery connecting pieces and cover plates according to claim 1, characterized in that, The inlet (22) is connected to the cooling chamber (21) through a first channel (24), and the outlet (23) is connected to the cooling chamber (21) through a second channel (25); and the cross-sectional area of ​​the first channel (24) is greater than the cross-sectional area of ​​the second channel (25).

7. The cooling device for laser welding of battery connecting pieces and cover plates according to claim 1, characterized in that, The cooling chamber (21) is formed at the top position within the heat transfer block (2).

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