Liquid cooling bottom plate structure of battery pack box body

Abstract

The invention discloses a liquid cooling bottom plate structure of a battery pack box body. A liquid cooling bottom plate is formed by splicing a left side plate, a middle plate and a right side plate; a splicing welding bead strip is arranged at each of the splicing positions of the left side and the right side of the middle plate, and the middle plate is connected with the left side plate and the right side plate through the two splicing welding bead strips; the two ends of the liquid cooling bottom plate are each provided with an end welding bead strip, and the two ends of the left side plate, the two ends of the middle plate and the two ends of the right side plate are connected with the two end welding bead strips respectively. A liquid cooling cavity is formed in the liquid cooling bottom plate, the splicing welding bead strip is located in the liquid cooling cavity, the two ends of the splicing welding bead strip extend to be connected with the two end welding bead strips respectively, and the two ends of the end welding bead strips extend outwards to exceed the liquid cooling cavity. The splicing welding bead strips and the end welding bead strips are welded and formed in a friction stir welding mode. According to the invention, the liquid cooling bottom plate is improved, so that the sealing performance and the cooling performance of the liquid cooling bottom plate are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid cooling bottom plates for battery boxes, and in particular to a liquid cooling bottom plate structure for a battery pack box. Background Art

[0002] The bottom plate of the battery pack box is usually a liquid cooling plate. The coolant flows in the liquid cooling plate to cool the battery pack. The cooling performance of the liquid cooling plate is related to the cooling effect of the battery pack. In addition, since the liquid cooling plate has to bear weight and the inside of the liquid cooling plate needs to contain coolant, if the sealing is not good, the liquid cooling plate is prone to leaking after bearing weight. Summary of the invention

[0003] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a liquid-cooled bottom plate structure for a battery pack box, and improves the liquid-cooled bottom plate to enhance the performance of the liquid-cooled bottom plate.

[0004] Technical solution: To achieve the above-mentioned purpose, the present invention provides a liquid-cooled bottom plate structure of a battery pack box, wherein the liquid-cooled bottom plate is spliced ​​by a left plate, a middle plate and a right plate; a splicing weld is respectively provided at the left and right side joints of the middle plate, and the middle plate is connected to the left and right plates through two splicing welds; an end weld is respectively provided at both ends of the liquid-cooled bottom plate, and the two ends of the left plate, the middle plate and the right plate are respectively connected to the two end welds; a liquid cooling cavity is provided in the liquid-cooled bottom plate, the splicing weld is located in the liquid cooling cavity, and the two ends of the splicing weld are respectively extended to connect with the two end welds, and the two ends of the end weld extend outwardly beyond the liquid cooling cavity.

[0005] Furthermore, the splicing weld strip and the end weld strip are both formed by friction stir welding.

[0006] Furthermore, the left plate, the middle plate and the right plate are all hollow plate bodies; the middle plate has a middle plate inner cavity, and connecting ports are respectively provided on the left and right sides of the middle plate inner cavity; the left plate has a left plate inner cavity, and a connecting port is provided on the side of the left plate inner cavity facing the middle plate; the right plate has a right plate inner cavity, and a connecting port is provided on the side of the right plate inner cavity facing the middle plate; the middle plate inner cavity, the left plate inner cavity and the right plate inner cavity are interconnected through the connecting ports and are combined together to form the liquid cooling cavity.

[0007] Furthermore, a water inlet nozzle is installed on the right side plate, and the water inlet nozzle is connected to the inner cavity of the right plate; a water outlet nozzle is installed on the left side plate, and the water outlet nozzle is connected to the inner cavity of the left plate.

[0008] Furthermore, a temporary support is provided in the connecting port; during the forming process of the spliced ​​welding strip by stir friction welding, the temporary support provides support for the stirring head; after the spliced ​​welding strip is welded and formed, the temporary support can be separated from the connecting port.

[0009] Furthermore, the temporary support is a soluble block embedded in the connecting port, and a dissolving liquid can be respectively poured into the inner cavity of the right plate and the inner cavity of the left plate through a water inlet nozzle and a water outlet nozzle, and the temporary support can be dissolved by the dissolving liquid, so that the temporary support can be separated from the connecting port.

[0010] Furthermore, each of the connecting ports is located at one end of the liquid-cooled base plate, and the water inlet nozzle and the water outlet nozzle are located at the other end of the liquid-cooled base plate; a reversing plate is arranged in the inner cavity of the middle plate, and one end of the reversing plate close to the connecting port is connected to the inner wall of the inner cavity of the middle plate, and the other end is separated from the inner wall of the inner cavity of the middle plate to form a reversing port.

[0011] Furthermore, a plurality of diverter plates are provided in the right plate inner cavity, the left plate inner cavity and the middle plate inner cavity, both ends of the diverter plates are spaced apart from the inner wall of the inner cavity, and a plurality of liquid cooling channels are separated in each inner cavity.

[0012] Furthermore, the liquid outlet areas of the connecting port and the reversing port are liquid redistribution areas; in the liquid redistribution area, the distance between the ends of each diverter plate and the inner wall of the inner cavity gradually decreases in the direction away from the connecting port or the reversing port.

[0013] Furthermore, in the liquid redistribution area, an angular diverter block is provided on one side of the end of the diverter plate facing the connecting port or the reversing port, and the tip of the angular diverter block faces the connecting port or the reversing port.

[0014] Beneficial effects: The liquid cooling bottom plate structure of a battery pack box of the present invention has the following beneficial effects:

[0015] 1) The liquid cooling bottom plate is composed of a left plate, a middle plate and a right plate. There is a splicing weld strip at the left and right joints of the middle plate, and there is an end weld strip at both ends of the liquid cooling bottom plate. The two ends of the splicing weld strip extend to connect with the two end weld strips, so that the overall sealing of the liquid cooling bottom plate is good and it is not easy to leak.

[0016] 2) A soluble temporary support is provided in the communication port. During the process of friction stir welding by the stirring head, the temporary support can provide support to prevent the communication port from being deformed under the pressure of the stirring head. After welding is completed, a dissolving liquid can be poured into the liquid cooling cavity to dissolve the temporary support, thereby opening the communication port.

[0017] 3) There are several manifolds in the liquid cooling cavity, and the several manifolds separate the liquid cooling cavity into several liquid cooling channels; there is a liquid redistribution area in the liquid cooling cavity, and in the liquid redistribution area, the distance between the end of each manifold and the inner wall of the inner cavity will be differentiated, and an angular manifold block is provided at the end of the manifold to make the liquid in the liquid cooling cavity more evenly distributed, thereby improving the cooling performance of the liquid cooling base plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Attached Figure 1 This is a schematic diagram of the external structure of the liquid cooling base plate;

[0019] Attached Figure 2 This is a bottom plan view of the liquid cooling base plate;

[0020] Attached Figure 3 Schematic diagram of the structure of the liquid cooling chamber. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings.

[0022] As attached Figures 1 to 3 The liquid cooling bottom plate structure of a battery pack box is composed of a left plate 1, a middle plate 2 and a right plate 3. The middle plate 2, the left plate 1 and the right plate 3 are spliced ​​together by welding. There is a splicing weld strip 4 at the splicing point on the left and right sides of the middle plate 2, and the middle plate 2 is connected to the left plate 1 and the right plate 3 through two splicing weld strips 4.

[0023] There is an end weld strip 5 at the front and rear ends of the liquid-cooled bottom plate respectively, the front and rear ends of the left side plate 1, the middle plate 2 and the right side plate 3 are aligned, and the front and rear ends of the left side plate 1, the middle plate 2 and the right side plate 3 are respectively connected to the two end weld strips 5, and the ends of the left side plate 1, the middle plate 2 and the right side plate 3 are connected together through the two end weld strips 5 to improve the connection strength of the left side plate 1, the middle plate 2 and the right side plate 3, so that the liquid-cooled bottom plate is not easy to leak after bearing weight.

[0024] There is a liquid cooling cavity 6 in the liquid cooling bottom plate, and the splicing weld strip 4 is located in the liquid cooling cavity 6. The two ends of the splicing weld strip 4 extend to connect with the two end weld strips 5, so that the overall sealing of the liquid cooling cavity 6 is good and it is not easy to leak. The two ends of the end weld strip 5 extend outward to exceed the liquid cooling cavity 6, that is, the length of the end weld strip 5 is greater than the width of the liquid cooling cavity 6, ensuring that the two ends of the liquid cooling cavity 6 are sealed by the end weld strip 5.

[0025] Specifically, the splicing weld strip 4 and the end weld strip 5 are both stir friction welding weld strips, that is, the splicing weld strip 4 and the end weld strip 5 are welded by stir friction welding, so that the bonding effect between the left plate 1, the middle plate 2 and the right plate 3 is better.

[0026] The left side plate 1, the middle plate 2 and the right side plate 3 are all hollow plates. Figure 3As shown in the figure, the middle plate 2 contains the middle plate inner cavity 7, and the left and right sides of the middle plate inner cavity 7 are respectively provided with connecting openings 8. The left plate 1 contains the left plate inner cavity 9, and the side of the left plate inner cavity 9 facing the middle plate 2 is provided with a connecting opening 8. The right plate 3 contains the right plate inner cavity 10, and the side of the right plate inner cavity 10 facing the middle plate 2 is provided with a connecting opening 8. When the left plate 1, the middle plate 2 and the right plate 3 are spliced ​​into a liquid-cooled bottom plate, the middle plate inner cavity 7, the left plate inner cavity 9 and the right plate inner cavity 10 are interconnected through the connecting openings 8, and are combined together to form the liquid-cooled cavity 6.

[0027] The right side plate 3 is provided with a water inlet nozzle 11, which is in communication with the right side plate inner cavity 10, and the coolant can enter the right side plate inner cavity 10 through the water inlet nozzle 11. The left side plate 1 is provided with a water outlet nozzle 12, which is in communication with the left side plate inner cavity 9, and the coolant in the left side plate inner cavity 9 can be discharged through the water outlet nozzle 12.

[0028] When the spliced ​​welding strip 4 is welded by friction stir welding, due to the existence of the connecting port 8, when the stirring head passes through the connecting port 8, the pressure of the stirring head may cause the connecting port 8 to deform or even collapse. To solve this problem, a temporary support is provided in the connecting port 8. During the forming process of the spliced ​​welding strip 4 by friction stir welding, the temporary support provides support for the stirring head to prevent the connecting port from being deformed under the pressure of the stirring head. After the spliced ​​welding strip 4 is welded and formed, the temporary support can be detached from the connecting port 8 to open the connecting port, so that the middle plate cavity 7, the left plate cavity 9 and the right plate cavity 10 are interconnected to form a liquid cooling cavity 6.

[0029] Specifically, the temporary support member is a soluble block embedded in the connecting port 8. The dissolving liquid can be injected into the right plate inner cavity 10 and the left plate inner cavity 9 respectively through the water inlet nozzle 11 and the water outlet nozzle 12. The temporary support member can be dissolved by the dissolving liquid, so that the temporary support member is separated from the connecting port 8, and the connecting port 8 is opened.

[0030] In one embodiment, the temporary support is a hard solid block containing calcium carbonate. Calcium carbonate can be dissolved in an acidic solution, and calcium carbonate still has good stability at 800-900°C, and can withstand the high temperature generated during the stir friction welding process. Generally speaking, the liquid-cooled bottom plate is an aluminum plate or a copper plate, so the dissolving liquid needs to select a suitable weakly acidic liquid so that the dissolving liquid can dissolve the calcium carbonate without corroding the aluminum plate. In addition, when the stirring head passes through the connecting port 8, the stirring head does not directly contact the temporary support, so as to avoid the stirring action of the stirring head directly crushing the temporary support.

[0031] As attached Figure 3As shown in , each of the connecting ports 8 is located at one end of the liquid cooling bottom plate, and the water inlet nozzle 11 and the water outlet nozzle 12 are located at the other end of the liquid cooling bottom plate. Therefore, after the coolant enters the right plate inner cavity 10 from the water inlet nozzle 11, it will first flow through the entire right plate inner cavity 10, and then enter the middle plate inner cavity 7 from the connecting port 8. Correspondingly, after the coolant in the middle plate inner cavity 7 enters the left plate inner cavity 9 from the connecting port 8, it will first flow through the entire left plate inner cavity 9, and then be discharged from the water outlet nozzle 12. A reversing plate 13 is provided in the middle plate inner cavity 7, and one end of the reversing plate 13 close to the connecting port 8 is connected to the inner wall of the middle plate inner cavity 7, and the other end is separated from the inner wall of the middle plate inner cavity 7 to form a reversing port 14. Due to the existence of the reversing plate 13, the coolant entering the middle plate inner cavity 7 will bypass the reversing port 14. In summary, the coolant has a longer flow path in the liquid cooling chamber 6, and has a better cooling effect on the battery pack.

[0032] A plurality of manifolds 15 are provided in the right plate inner cavity 10, the left plate inner cavity 9 and the middle plate inner cavity 7. The two ends of the manifolds 15 are spaced apart from the inner wall of the inner cavity, and a plurality of liquid cooling channels 16 are separated in each inner cavity. Due to the presence of the manifolds 15, the contact area between the coolant and the liquid cooling bottom plate is larger, and the heat transfer efficiency between the coolant and the liquid cooling bottom plate is higher, thereby improving the cooling performance of the liquid cooling bottom plate.

[0033] As attached Figure 3 As shown in , the liquid outlet area of ​​the connecting port 8 and the reversing port 14 is a liquid redistribution area 17. In the liquid redistribution area 17, the distance between the end of each diverter plate 15 and the inner wall of the inner cavity gradually decreases in the direction away from the connecting port 8 or the reversing port 14, thereby playing a diversion role, so that the flow distribution in each liquid cooling channel 16 is relatively uniform. In the liquid redistribution area 17, an angular diverter block 18 is provided on the side of the end of the diverter plate 15 facing the connecting port 8 or the reversing port 14, and the tip of the angular diverter block 18 faces the connecting port 8 or the reversing port 14. By providing the angular diverter block 18, the flow distribution in each liquid cooling channel 16 can be made more uniform. The flow distribution in each liquid cooling channel 16 is uniform, which is conducive to improving the cooling performance of the liquid cooling base plate.

[0034] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A liquid cooling bottom plate structure of a battery pack box, characterized in that: The liquid cooling bottom plate is formed by splicing a left side plate (1), a middle plate (2) and a right side plate (3); a splicing weld strip (4) is respectively provided at the splicing positions of the left and right sides of the middle plate (2), and the middle plate (2) is connected to the left side plate (1) and the right side plate (3) through the two splicing weld strips (4); an end weld strip (5) is respectively provided at both ends of the liquid cooling bottom plate, and the two ends of the left side plate (1), the middle plate (2) and the right side plate (3) are respectively connected to the two end weld strips (5); A liquid cooling cavity (6) is provided in the liquid cooling bottom plate, a splicing weld strip (4) is located in the liquid cooling cavity (6), two ends of the splicing weld strip (4) respectively extend to connect with two end weld strips (5), and two ends of the end weld strip (5) extend outwards beyond the liquid cooling cavity (6).

2. The liquid cooling bottom plate structure of a battery pack box according to claim 1, characterized in that: The splicing weld strip (4) and the end weld strip (5) are both formed by welding in a stir friction welding manner.

3. The liquid cooling bottom plate structure of a battery pack box according to claim 2, characterized in that: The left plate (1), the middle plate (2) and the right plate (3) are all hollow plate bodies; the middle plate (2) contains a middle plate inner cavity (7), and connecting openings (8) are respectively arranged on the left and right sides of the middle plate inner cavity (7); the left plate (1) contains a left plate inner cavity (9), and a connecting opening (8) is arranged on the side of the left plate inner cavity (9) facing the middle plate (2); the right plate (3) contains a right plate inner cavity (10), and a connecting opening (8) is arranged on the side of the right plate inner cavity (10) facing the middle plate (2); the middle plate inner cavity (7), the left plate inner cavity (9) and the right plate inner cavity (10) are interconnected through the respective connecting openings (8), and are combined together to form the liquid cooling cavity (6).

4. The liquid cooling bottom plate structure of a battery pack box according to claim 3, characterized in that: The right side plate (3) is provided with a water inlet nozzle (11), which is in communication with the inner cavity (10) of the right plate; the left side plate (1) is provided with a water outlet nozzle (12), which is in communication with the inner cavity (9) of the left plate.

5. The liquid cooling bottom plate structure of a battery pack box according to claim 4, characterized in that: A temporary support piece is provided in the communication port (8); during the process of forming the spliced ​​welding strip (4) by means of stir friction welding, the temporary support piece provides support for the stirring head; after the spliced ​​welding strip (4) is welded and formed, the temporary support piece can be separated from the communication port (8).

6. The liquid cooling bottom plate structure of a battery pack box according to claim 5, characterized in that: The temporary support member is a soluble block embedded in the connecting port (8). Dissolving liquid can be injected into the right plate inner cavity (10) and the left plate inner cavity (9) respectively through a water inlet nozzle (11) and a water outlet nozzle (12). The temporary support member can be dissolved by the dissolving liquid, so that the temporary support member is separated from the connecting port (8).

7. The liquid cooling bottom plate structure of a battery pack box according to claim 4, characterized in that: Each of the connecting ports (8) is located at one end of the liquid cooling base plate, and the water inlet nozzle (11) and the water outlet nozzle (12) are located at the other end of the liquid cooling base plate; a reversing plate (13) is arranged in the middle plate inner cavity (7), and one end of the reversing plate (13) close to the connecting port (8) is connected to the inner wall of the middle plate inner cavity (7), and the other end is separated from the inner wall of the middle plate inner cavity (7), forming a reversing port (14).

8. The liquid cooling bottom plate structure of a battery pack box according to claim 7, characterized in that: A plurality of diverter plates (15) are arranged in the right plate inner cavity (10), the left plate inner cavity (9) and the middle plate inner cavity (7), the two ends of the diverter plates (15) are spaced from the inner wall of the inner cavity, and a plurality of liquid cooling channels (16) are separated in each inner cavity.

9. The liquid cooling bottom plate structure of a battery pack box according to claim 8, characterized in that: The liquid outlet area of ​​the communication port (8) and the reversing port (14) is a liquid redistribution area (17); in the liquid redistribution area (17), the distance between the end of each diverter plate (15) and the inner wall of the inner cavity gradually decreases in the direction away from the communication port (8) or the reversing port (14).

10. The liquid cooling bottom plate structure of a battery pack box according to claim 9, characterized in that: In the liquid redistribution area (17), an angular diverter block (18) is provided on one side of the end of the diverter plate (15) facing the connecting port (8) or the reversing port (14), and the tip of the angular diverter block (18) faces the connecting port (8) or the reversing port (14).

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