Side surface bottom double-channel liquid cooling immersed battery box

Abstract

The invention discloses a liquid-cooled immersed battery box with two channels at the side surface and the bottom, which is based on the fact that a battery cell module is directly immersed in synthetic oil, so that a heating source battery cell, an aluminum row and the like are directly and fully contacted with the synthetic oil, the heat dissipation is more uniform and efficient, the temperature gradient of a battery can be effectively reduced, and the local overheating phenomenon is reduced. The main heat dissipation mode is a novel cooling scheme that the heat in the synthetic oil is taken away by using two channels of a side liquid cooling device and a liquid cooling bottom plate after the heat is conducted into the synthetic oil through a battery cell aluminum row and the like. Compared with a traditional liquid-cooled battery box, namely, a mode of cooling by only utilizing a bottom cooling water channel, the liquid-cooled battery box has more obvious cooling advantages, and due to the fact that contact conduction has a larger contact surface area, heat exchange can be more efficiently carried out, the problem of the pain point that the head of a battery cell is hot and the foot of the battery cell is cold in traditional liquid cooling is solved, and the service life of the battery cell is prolonged. And compared with a cooling circulation dynamic oil scheme, the cost is lower, and the reliability is higher.

Description

Technical Field

[0001] The present invention relates to the field of battery boxes, and in particular to a side-bottom dual-channel liquid-cooled immersion battery box. Background Art

[0002] When the battery module is charged and discharged, it will generate heat. Excessive temperature and uneven local temperature inside the battery will seriously reduce the battery life. The heat dissipation performance of the battery module is an important factor affecting the battery's working performance, working efficiency, service life, and safety. Currently, in the existing liquid-cooled battery box structures, cooling water channels are provided at the bottom for cooling and heat dissipation. However, this will cause the problem of higher temperature at the top and lower temperature at the bottom of the battery cells, greatly reducing the operating temperature range of the battery and the energy efficiency of the entire battery box, shortening the service life of the battery, and even potentially causing safety hazards.

[0003] Problems of the prior art:

[0004] 1. In the existing battery boxes, the temperature distribution of the modules is uneven and there is local overheating, which is not conducive to the long-term use of the battery system, and the safety and reliability cannot be guaranteed;

[0005] 2. The liquid-cooled battery boxes used in the market only dissipate heat through bottom liquid cooling. The temperature of the battery cell terminals and aluminum busbars is still too high and they are the main heat source generation sites, resulting in a large temperature difference in the overall battery box;

[0006] 3. The existing immersion battery boxes use the method of circulating oil for cooling, which has many drawbacks. For example, the path through which the circulating oil passes is complex, there is a hidden danger of oil leakage, and the after-sales service is difficult.

[0007] Therefore, it is necessary to improve such a structure to overcome the above defects. Summary of the Invention

[0008] The purpose of the present invention is to provide a side-bottom dual-channel liquid-cooled immersion battery box to solve the problems raised in the above background art.

[0009] To achieve the above purpose, the present invention provides the following technical solutions:

[0010] A side-bottom dual-channel liquid-cooled immersion battery box, including a battery box; a battery module is arranged inside the battery box, and the battery module is immersed in insulating synthetic oil. Liquid-cooled bottom inlet and liquid-cooled bottom outlet are respectively and communicatively arranged on the left and right sides of the base at the front end of the battery box; it also includes a side liquid-cooling device, and the side liquid-cooling device includes an upper liquid inlet plate and a lower liquid discharge plate. Both the upper liquid inlet plate and the lower liquid discharge plate are hollow, and at the same time, a plurality of heat exchange plates are communicatively arranged at the rear sides of the upper liquid inlet plate and the lower liquid discharge plate at evenly spaced intervals. A U-shaped flow channel is opened inside the heat exchange plate, and the upper and lower ends at the front end of the flow channel are respectively communicatively arranged with the upper liquid inlet plate and the lower liquid discharge plate; the flow channel structure is simple

[0011] The front ends of the upper liquid inlet plate and the lower liquid discharge plate are respectively communicated with a liquid cooling channel liquid inlet and a liquid cooling channel liquid outlet.

[0012] Furthermore, the side liquid cooling device is integrally formed by extruding profiles into pipelines and then welding.

[0013] Furthermore, the side liquid cooling device is formed by bending and welding an aluminum pipe, a copper pipe or other metal pipes.

[0014] Furthermore, the side liquid cooling device is formed by plastic injection molding of a non-metal pipe.

[0015] Furthermore, a fixing strip is arranged at the rear side of the side liquid cooling device.

[0016] Furthermore, the liquid cooling bottom plate liquid inlet and the liquid cooling bottom plate liquid outlet are respectively used for the entry and discharge of the coolant inside the liquid cooling bottom plate; the inside of the liquid cooling bottom plate is integrally serpentine and hollow; the liquid cooling bottom plate liquid inlet, the liquid cooling bottom plate and the liquid cooling bottom plate liquid outlet constitute a bottom cooling system.

[0017] Furthermore, the fixing strip is connected to the rear end of the heat exchange plate through an elastic fixing device.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. The insulating synthetic oil (I-10℃ transformer oil) used in the immersion battery box has the advantages of high flash point, good insulation and large specific heat capacity, which can make the battery box in a safer environment compared with ordinary liquid cooling, and can effectively ensure the fire protection problem of the battery box.

[0020] 2. Cooling is carried out simultaneously through the side liquid cooling device and the bottom cooling system, so that the heat generated by the heating of the battery cells is cooled by exchanging heat with the cooling system. This invention scheme can cool between the modules, and can make the whole immersion oil fully and efficiently exchange heat and be cooled. The overall cooling effect is improved, the service life of the battery is prolonged and the safety is improved.

[0021] 3. The dual-channel liquid cooling scheme ensures that the battery cells are in a temperature range more friendly to the performance of the battery cells. Even if there are multiple continuous charge and discharge cycles, the temperature rise and the maximum temperature still have obvious advantages compared with the current liquid cooling method, and the probability of thermal runaway of the battery cells is greatly reduced from the source. Description of the Drawings

[0022] Figure 1 It is an exploded view of a side-bottom dual-channel liquid cooling immersion battery box.

[0023] Figure 2 It is a structural schematic diagram of a side-bottom dual-channel liquid cooling immersion battery box.

[0024] Figure 3It is a front view of a side-bottom dual-channel liquid-cooled immersion battery box.

[0025] Figure 4 It is a top view of a side-bottom dual-channel liquid-cooled immersion battery box.

[0026] Figure 5 It is Figure 4 a cross-sectional view taken along the A-A direction in

[0027] Figure 6 It is a schematic diagram of the internal structure of a side-bottom dual-channel liquid-cooled immersion battery box after removing the top cover.

[0028] Figure 7 It is a schematic diagram of the structure of the side liquid-cooling device in a side-bottom dual-channel liquid-cooled immersion battery box.

[0029] Figure 8 It is a schematic diagram of the structure of the bottom cooling system in a side-bottom dual-channel liquid-cooled immersion battery box.

[0030] Figure 9 It is a schematic diagram of the structure of the side liquid-cooling device in some embodiments of this solution.

[0031] Figure 10 In Figure 9 a partial enlarged view at position a.

[0032] Figure 11 It is a schematic diagram of the structure of the elastic fixing device in some embodiments of this solution.

[0033] Figure 12 It is a schematic diagram of the structure of the elastic fixing device from another angle in some embodiments of this solution. Specific embodiments

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0035] Please refer to Figures 1-8 , a side-bottom dual-channel liquid-cooled immersion battery box, including battery box 1;

[0036] A battery module 2 is arranged inside the battery box 1. The battery module 2 is immersed in an insulating synthetic oil, which is I - 10℃ transformer oil, having the advantages of high flash point, good insulation and relatively large specific heat capacity;

[0037] Liquid - cooled bottom plate liquid - outlet 102 and liquid - cooled bottom plate liquid - inlet 101 are respectively and communicatively arranged on the left and right sides of the base at the front end of the battery box 1; Figure 8 As shown, the liquid - cooled bottom plate liquid - inlet 101 and the liquid - cooled bottom plate liquid - outlet 102 are respectively used for the entry and discharge of the coolant inside the liquid - cooled bottom plate 103. The inside of the liquid - cooled bottom plate 103 is integrally serpentine and hollow - arranged. The liquid - cooled bottom plate liquid - inlet 101, the liquid - cooled bottom plate 103 and the liquid - cooled bottom plate liquid - outlet 102 constitute a bottom cooling system;

[0038] It further includes a side liquid - cooling device 2. The side liquid - cooling device 2 includes an upper liquid - inlet plate 201 and a lower liquid - discharge plate 202. Both the upper liquid - inlet plate 201 and the lower liquid - discharge plate 202 are hollow - arranged. At the same time, a plurality of heat - exchange plates 203 are communicatively arranged at the rear sides of the upper liquid - inlet plate 201 and the lower liquid - discharge plate 202 at uniform intervals;

[0039] In this solution, a plurality of groups of the battery modules 2 are arranged at intervals, and the heat - exchange plates 203 are located between adjacent battery modules 2;

[0040] A U - shaped flow channel 204 is formed inside the heat - exchange plate 203. The upper and lower ends at the front end of the flow channel 204 are respectively communicatively arranged with the upper liquid - inlet plate 201 and the lower liquid - discharge plate 202;

[0041] A fixing strip 3 is further arranged at the rear side of the side liquid - cooling device 2. The fixing strip 3 is fixedly connected to the rear end of the heat - exchange plate 203, and the left and right ends of the fixing strip 3 are fixedly connected to the side wall of the battery box 1, thereby ensuring that the rear end of the heat - exchange plate 203 of the side liquid - cooling device 2 is supported.

[0042] A liquid - cooling channel liquid - inlet 205 and a liquid - cooling channel liquid - outlet 206 are respectively communicatively arranged at the front ends of the upper liquid - inlet plate 201 and the lower liquid - discharge plate 202;

[0043] The coolant enters the upper liquid - inlet plate 201 from the liquid - cooling channel liquid - inlet 205. The coolant inside the upper liquid - inlet plate 201 enters the flow channel from above the front end of the flow channel 204, then enters the lower liquid - discharge plate 202 from the bottom of the flow channel 204, and finally is discharged from the liquid - cooling channel liquid - outlet 206;

[0044] The advantage of this solution is that the coolant entering the upper liquid inlet plate 201 is at a relatively low temperature, while the transformer oil with a higher temperature in the battery box 1 will rise. At this time, the temperature difference between the coolant near the upper liquid inlet plate 201 and the transformer oil will be larger than that at other positions, and its heat exchange efficiency will be higher. This is because when the temperature difference increases, the heat transfer rate from the high-temperature area to the low-temperature area increases, the thermal resistance decreases, and the heat transfer coefficient increases.

[0045] The side liquid cooling device 2 is formed by extruding profiles into pipelines and then welding them together. It can also be replaced with other metal pipes such as aluminum pipes and copper pipes that are bent and welded, or non-metal pipes.

[0046] If it is a non-metal pipe, it can be formed by plastic injection molding.

[0047] Laying and fixing method of the side liquid cooling device: First, install the module, then install the side liquid cooling device on the side of the module, and then fix the fixing strip to the side liquid cooling device with screws to prevent loosening, and then fix the fixing strip to the inner wall of the battery box. Then, fix the inlet and outlet water ports on the battery box panel with nuts and sealing rings to ensure the overall sealing of the battery box body. Finally, structural adhesive can also be used for further fixation to ensure the firmness of the side liquid cooling device.

[0048] In this solution, the principle is that the coolant enters from the two liquid inlet ports on the right and returns from the two liquid return ports on the left, as shown in the appendix Figure 3 . Cooling is carried out simultaneously through the side liquid cooling device and the bottom liquid cooling bottom plate, so that the heat generated by the heating of the battery cells in the battery module 2 is exchanged with the cooling system to achieve temperature reduction.

[0049] This invention solution can cool between modules, enabling the overall immersion oil to be fully and efficiently heat-exchanged and cooled. It improves the overall cooling effect, extends the battery service life, and improves safety.

[0050] Such as Figures 9-12 , in some embodiments of this solution, the fixing strip 3 is connected to the rear end of the heat exchange plate 203 through an elastic fixing device 310;

[0051] When the battery module 2 is working, it will heat the insulating synthetic oil, and the insulating synthetic oil will heat the heat exchange plate 203. Since this heating is not uniform, at this time, the heat exchange plate 203 will generate thermal stress due to uneven heating, resulting in plate deformation. If the fixing strip 3 is welded to the rear end of the heat exchange plate 203 at this time, the stress of the plate deformation will be concentrated at the solder joints. After the battery module 2 is started repeatedly for many times, it is easy to cause the solder joints at the rear end of the fixing strip 3 and the heat exchange plate 203 to break open. In this solution, the elastic fixing device 310 is used to connect the fixing strip 3 and the heat exchange plate 203. Therefore, the deformation of the heat exchange plate 203 will be absorbed by the elastic fixing device 310, thus ensuring that the rear end of the heat exchange plate 203 can always be supported;

[0052] Specifically, the elastic fixing device 310 includes a fixing frame 311. The top of the fixing frame 311 is fixedly connected to the fixing bar 3 by bolts. A circular installation groove 312 is formed in the center of the fixing frame 311. The inner wall of the installation groove 312 is fixedly connected to a central disk 314 by a plurality of arc-shaped elastic connecting pieces 313. The central disk 314 is located at the center of the installation groove 312, and the elastic connecting pieces 313 are arranged in a circular array. One end of the central disk 314 is provided with a connecting shaft 315. The end of the connecting shaft 315 is fixedly connected to the heat exchange plate 203 by bolts, and there is a gap between the central disk 314 and the heat exchange plate 203.

[0053] When this solution is put into use, even if the rear end of the heat exchange plate 203 undergoes displacement in the horizontal direction or in the vertical direction, at this time, the arc-shaped elastic connecting pieces 313 can deform correspondingly, thereby absorbing the stress generated by these deformations. Furthermore, it is ensured that the rear end of the heat exchange plate 203 is always fixed.

[0054] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use, or the orientation or positional relationship commonly understood by those skilled in the art. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance. In the description of the present invention, it should also be noted that unless otherwise clearly specified and defined, terms such as "set", "connect" should be understood in a broad sense. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A side and bottom dual-channel liquid-cooled immersion battery box, comprising a battery box; characterized in that: A battery module is arranged inside the battery box, and the battery module is immersed in insulating synthetic oil. Liquid-cooled bottom plate liquid inlets and liquid-cooled bottom plate liquid outlets are respectively and communicatively arranged on the left and right sides of the base at the front end of the battery box; A side liquid cooling device is further included. The side liquid cooling device includes an upper liquid inlet plate and a lower liquid discharge plate. Both the upper liquid inlet plate and the lower liquid discharge plate are hollow. At the same time, a plurality of heat exchange plates are communicatively arranged at the rear sides of the upper liquid inlet plate and the lower liquid discharge plate at uniform intervals. A U-shaped flow channel is arranged inside the heat exchange plate, and the upper and lower ends at the front end of the flow channel are respectively communicatively arranged with the upper liquid inlet plate and the lower liquid discharge plate; Liquid-cooled channel liquid inlets and liquid-cooled channel liquid outlets are respectively communicatively arranged at the front ends of the upper liquid inlet plate and the lower liquid discharge plate.

2. A side and bottom dual-channel liquid-cooled immersion battery box according to claim 1, characterized in that: The side liquid cooling device is integrally formed by extrusion of profiles and then welding.

3. The side and bottom dual-channel liquid-cooled immersion battery box according to claim 1, characterized in that: The side liquid cooling device is formed by bending and welding an aluminum pipe, a copper pipe or other metal pipes.

4. The side and bottom dual-channel liquid-cooled immersion battery box according to claim 1, characterized in that: The side liquid cooling device is formed by plastic injection molding of a non-metal pipe.

5. The side and bottom dual-channel liquid-cooled immersion battery box according to claim 1, characterized in that: A fixing strip is further arranged at the rear side of the side liquid cooling device.

6. The side and bottom dual-channel liquid-cooled immersion battery box according to claim 1, characterized in that: The insulating synthetic oil in which the battery module is immersed is No. I-10℃ transformer oil.

7. The side and bottom dual-channel liquid-cooled immersion battery box according to claim 1, characterized in that: The liquid-cooled bottom plate liquid inlets and the liquid-cooled bottom plate liquid outlets are respectively used for the entry and discharge of the coolant inside the liquid-cooled bottom plate; The inside of the liquid-cooled bottom plate is overall serpentine and hollow; The liquid-cooled bottom plate liquid inlets, the liquid-cooled bottom plate and the liquid-cooled bottom plate liquid outlets form a bottom cooling system.

8. The side and bottom dual-channel liquid-cooled immersion battery box according to claim 1, characterized in that: The fixing strip is connected to the rear end of the heat exchange plate through an elastic fixing device.

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