Immersed liquid cooling lithium battery PACK heat dissipation structure

Abstract

The invention relates to a heat dissipation structure of an immersed liquid-cooled lithium battery PACK, the lithium battery PACK comprises four battery modules, and each battery module comprises 13 single battery cells. Four cooling liquid inlets and four liquid outlets are formed in a lithium battery PACK box body, electric control proportional switches are installed on the liquid inlets, if the temperature of a certain battery cell exceeds the calibrated temperature, a switch for controlling the battery cell will be automatically turned off, meanwhile, an opening of the proportional switch on the liquid inlet corresponding to the battery module will be enlarged, input of cooling liquid will be increased, and the temperature of the battery module will be increased. And after the battery cell is cooled to a safe temperature, controlling the switch of the battery cell to be automatically turned on, and automatically adjusting the opening of the proportional switch to a normal working state. On the basis of an existing lithium battery heat dissipation structure, the situation that the working efficiency of the battery module is reduced and the service life of the battery module is affected due to the fact that the temperature difference in the battery module is too large is avoided, and the problem of battery heating can be effectively solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery energy storage safety, and in particular relates to an immersion liquid-cooled lithium battery PACK heat dissipation structure. Background Art

[0002] New energy batteries have developed rapidly in recent years. As the core energy storage component in the automotive and other industries, the safety of lithium-ion batteries is the top priority of the entire battery industry. When lithium batteries are working for a long time, the battery temperature will rise significantly. If the battery is not effectively cooled, the battery temperature may be too high and stop working. More seriously, it may cause battery damage, even paralysis of the entire battery energy storage system, or even cause a fire.

[0003] Among the existing technologies, there are good solutions to the heat dissipation problem of battery energy storage systems, such as air cooling, immersion liquid cooling, liquid cooling plate cooling, etc. However, the existing technology cannot monitor the individual cells inside the battery module in real time, because during the operation of the battery module, a single cell may have an abnormally high temperature. At this time, if no measures are taken, the high temperature caused by a single cell may be transmitted to the surrounding cells or even the entire module.

[0004] Immersion cooling is one of the effective methods for controlling the temperature of battery modules. Liquid cooling can quickly cool the battery module and make the battery module have better temperature uniformity. Summary of the invention

[0005] The present invention proposes an immersion liquid-cooled lithium battery PACK heat dissipation structure, which has the function of dissipating heat from the battery module in the lithium battery PACK, ensuring that the temperature of the battery module is within a safe temperature range, making the temperature of each battery cell in the battery module uniform, and reducing the temperature difference in the battery module. At the same time, it ensures that the temperature of a single battery cell in the battery module can be monitored in real time to avoid damage to the entire lithium battery PACK caused by abnormally high temperature of a single battery cell. When the temperature of a battery cell in a battery module suddenly rises, the opening of the proportional switch on the liquid inlet corresponding to the battery module will increase, increasing the input of coolant, so that the heating battery cell can be quickly cooled down.

[0006] The technical solution of the present invention is:

[0007] An immersion liquid-cooled lithium battery PACK heat dissipation structure comprises a battery module, a PACK box, a coolant, a liquid inlet, a liquid outlet, an electronically controlled proportional switch and a temperature monitoring system.

[0008] The lithium battery PACK comprises four battery modules, which are positioned and fixed by positioning support convex strips on the box body, and each battery module has large gaps at the top, bottom, left, right, front and back.

[0009] Furthermore, each lithium battery module is completely wrapped by insulating material, and the four lithium battery modules are completely immersed in coolant.

[0010] Furthermore, each module is composed of 13 battery cells evenly arranged, and adjacent battery cells are separated by insulating heat shields. Each battery cell is equipped with a temperature sensor for monitoring the real-time temperature of the battery cell.

[0011] In the immersion liquid-cooled lithium battery PACK heat dissipation structure, the coolant enters the box through the liquid inlet on the lithium battery PACK box and is discharged from the box through the liquid outlet on the lithium battery PACK box. The liquid inlet is located on the front side of the lithium battery PACK box, and the liquid outlet is located on the rear side of the lithium battery PACK box. The liquid inlet and outlet of the lithium battery PACK box are respectively installed with electronically controlled proportional switches.

[0012] Furthermore, if the coolant temperature is too high, the temperature sensor on the lithium battery PACK box will transmit a signal to the temperature monitoring system, and the temperature monitoring system will control the proportional switch of the coolant inlet to increase its opening and increase the flow of the coolant.

[0013] Furthermore, when the temperature of a battery cell in a battery module suddenly rises, the opening of the proportional switch on the liquid inlet corresponding to the battery module will increase, increasing the input of coolant and allowing the heated battery cell to be cooled quickly.

[0014] Furthermore, in the lithium battery PACK box, the coolant level is 5-10 cm higher than the top surface of the battery module and 10-15 cm below the top cover of the lithium battery PACK shell.

[0015] The cooling liquid of the immersion liquid cooling method adopts fluorinated liquid.

[0016] The beneficial effects of the present invention are:

[0017] The contact area between the lithium battery module and the coolant is increased, and the cooling efficiency of the lithium battery module is improved.

[0018] If the temperature of a battery cell exceeds the calibrated temperature, the switch controlling the battery cell will be automatically closed. At the same time, the opening of the proportional switch on the liquid inlet corresponding to the battery module will be enlarged to increase the input of coolant. After the battery cell is cooled to a safe temperature, the switch controlling the battery cell will be automatically opened, and the proportional switch opening will automatically adjust to a normal working state. The present invention can effectively solve the problem of high-temperature heat dissipation of the battery and the problem of abnormally high temperature of the single battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the heat dissipation structure of an immersion liquid-cooled lithium battery PACK (front view).

[0020] Figure 2 This is a schematic diagram of the heat dissipation structure of an immersion liquid-cooled lithium battery PACK (top view and cross-sectional view).

[0021] Figure 3 A schematic diagram of the structure of a battery module.

[0022] FIG. 4 is a schematic diagram showing the structure of a battery cell. DETAILED DESCRIPTION

[0023] The embodiments of the present invention are described in detail below, but the protection scope of the present invention is not limited to the following embodiments.

[0024] Combination Figure 1 4 , an embodiment of the present invention is described.

[0025] The present invention provides an immersion type liquid-cooled lithium battery PACK heat dissipation structure, comprising a lithium battery PACK box (1), a lithium battery module (2), a coolant (3), a top cover (4), an insulating layer (5), a temperature sensor (6), a liquid inlet (7), a liquid outlet (8), and an electronically controlled proportional switch (9); a positioning support convex strip (10) is arranged on the lithium battery PACK box (1); the lithium battery module (2) comprises a battery cell (21) and a heat insulation sheet (22); and a temperature sensor (211) and an automatic switch (210) are installed on the battery cell.

[0026] The insulating layer (5) is evenly applied to the outer layer of the lithium battery module (2) to prevent the coolant (3) from flowing into the lithium battery module (2).

[0027] Inside the lithium battery module (2), the battery cells (21) are evenly arranged, and a heat insulation sheet (22) is installed between adjacent battery cells (21).

[0028] A temperature sensor (211) and an automatic switch (210) are installed on each battery core (21).

[0029] The lithium battery module (2) is positioned and fixed by the positioning support convex strip (10).

[0030] Temperature sensors (6) are installed at the bottom and top of each lithium battery module (2).

[0031] The liquid inlet (7) is arranged on the front side of the lithium battery PACK box (1), and the liquid outlet (8) is arranged on the rear side of the lithium battery PACK box (1).

[0032] The coolant level is 5 cm higher than the top surface of the lithium battery module (2) and 10 cm below the top cover of the lithium battery PACK box (1).

[0033] The cooling liquid (3) is a fluorinated liquid.

Claims

1. An immersion liquid-cooled lithium battery PACK heat dissipation structure, characterized in that: The immersion liquid-cooled lithium battery PACK heat dissipation structure includes a battery module, a PACK box, a coolant and a temperature monitoring system. The battery module, the temperature monitoring system and the coolant inlet and outlet are installed inside the immersion liquid-cooled lithium battery PACK box.

2. According to claim 1, an immersion liquid-cooled lithium battery PACK heat dissipation structure is characterized in that: The immersion liquid-cooled lithium battery PACK box is a closed structure, and 4 lithium battery module installation slots are arranged in the immersion liquid-cooled lithium battery PACK box. Each lithium battery module is completely wrapped by insulating material, and the 4 lithium battery modules are completely immersed in the coolant.

3. According to claim 1, an immersion liquid-cooled lithium battery PACK heat dissipation structure is characterized in that: Each lithium battery module contains 13 individual cells evenly arranged and connected in series. Adjacent cells are separated by insulating heat shields. Each cell is equipped with a temperature sensor to monitor the real-time temperature of the cell. At the same time, a temperature sensor is installed in the lithium battery PACK box to collect the real-time working temperature of the coolant.

4. According to claim 1, an immersion liquid-cooled lithium battery PACK heat dissipation structure is characterized in that: A temperature monitoring system is installed in the lithium battery PACK, and the temperature monitoring system is connected to the temperature sensor on each battery cell and the coolant temperature sensor on the lithium battery PACK box to collect real-time temperature data of the 4×13 battery cells and the coolant.

5. According to claim 1, an immersion liquid-cooled lithium battery PACK heat dissipation structure is characterized in that: The coolant enters the box through the liquid inlet on the lithium battery PACK box and is discharged from the box through the liquid outlet on the lithium battery PACK box. The liquid inlet is located on the front side of the lithium battery PACK box, and the liquid outlet is located on the rear side of the lithium battery PACK box. The liquid inlet (or liquid outlet) of the lithium battery PACK box is installed with an electronically controlled proportional switch, and the number of liquid inlets and liquid outlets is 2-4 pairs.

6. According to claim 1, an immersion liquid-cooled lithium battery PACK heat dissipation structure is characterized in that: The temperature monitoring system will control the opening size of the proportional switch at the liquid inlet according to the temperature of the battery cell and the coolant transmitted by the temperature sensor. When the temperature of the battery cell in a battery module suddenly rises, the flow rate of the proportional switch on the liquid inlet corresponding to the battery module will increase, increasing the input of coolant and quickly cooling the heated battery cell.

7. According to claim 1, an immersion liquid-cooled lithium battery PACK heat dissipation structure is characterized in that: There are positioning support ridges at the bottom of the lithium battery PACK box. The positioning support ridges position and fix the four battery modules, and leave gaps around each battery module to ensure that each battery module is completely immersed in the coolant.

8. According to claim 1, the immersion liquid-cooled lithium battery PACK heat dissipation structure is characterized in that: In the lithium battery PACK box, the coolant level is higher than the top surface of the battery module, 5-10 cm below the top cover of the lithium battery PACK shell, and temperature sensors are installed at the bottom and top of each battery module, and the top temperature sensor is located lower than the top surface of the battery module.

9. The immersion liquid-cooled lithium battery PACK heat dissipation structure according to claim 1, characterized in that: The cooling liquid of the immersion liquid cooling method adopts fluorinated liquid.

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