Immersed liquid-cooled battery module

Abstract

The utility model discloses an immersed liquid-cooled battery module. The immersed liquid-cooled battery module comprises a battery box lower cavity, a battery box upper cover plate and a plurality of battery cells, the battery cells are arranged in the battery box lower cavity in series and parallel, the battery box upper cover plate is fixedly installed on the battery box lower cavity through screws, gaps among the battery cells after the battery cells are connected in series and parallel and gaps between the battery box lower cavity and the battery box upper cover plate form a flow channel, the flow channel is in a pipe network type, and a cooling medium flows in the flow channel. A cooling medium adopts a fluorinated solution; compared with the prior art, the utility model has the advantages that the sealing reliability is higher, the pressure loss of the pipe network type flow channel is smaller, the flow distribution is more uniform, the viscosity of the fluorinated liquid is low, the safety is high, all the battery cells are arranged in the cooling medium, the cooling medium is in direct contact with the battery cells for heat exchange, the temperature rise of the battery cells is better reduced, and the uniform temperature of the battery cells is kept; the battery cell is always arranged in the fire-fighting medium, so that the fire-fighting safety of the battery module is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of energy storage batteries, in particular to an immersion liquid-cooled battery module. Background Art

[0002] For energy storage batteries, if the battery cell temperature is too high, there is a risk of thermal runaway, or even fire and explosion. If the temperature difference between different battery cells is too large, it will cause the difference in the internal resistance of the battery to increase, which will reduce the battery life. In severe cases, uneven heat generation of the battery can also lead to thermal runaway.

[0003] At present, forced air cooling and indirect liquid cooling are mainly used for temperature control of battery modules. The cooling medium of forced air cooling is air, and the thermal conductivity, specific heat capacity and density of air are relatively small, which leads to poor heat dissipation of battery cells and poor temperature control. Indirect liquid cooling generally uses aluminum water cooling plates to dissipate heat from the bottom of the battery cells. Although the thermal conductivity, specific heat capacity and density of the cooling medium are relatively large, the water cooling plate is equivalent to adding a thermal resistance between the battery cells and the cooling medium, which affects the heat dissipation performance. At the same time, forced air cooling and indirect liquid cooling are of no benefit to the fire safety of battery modules.

[0004] Therefore, an immersion liquid-cooled battery module is proposed to solve the above problems. Utility Model Content

[0005] In view of the defects in the prior art, the purpose of the utility model is to provide an immersion liquid-cooled battery module with higher sealing reliability, smaller pressure loss in the pipe network flow channel, more uniform flow distribution, low viscosity of the fluorinated liquid and high safety. All battery cells are placed in a cooling medium, and the cooling medium is in direct contact with the battery cells for heat exchange, which better reduces the temperature rise of the battery cells and maintains a uniform temperature of the battery cells. At the same time, the fluorinated liquid is non-flammable and is an excellent fire-fighting medium, which allows the battery cells to be always placed in the fire-fighting medium, thereby improving the fire safety of the battery module.

[0006] Specifically, the technical problem to be solved by the utility model is to provide an immersion liquid-cooled battery module in view of the deficiencies in the above-mentioned prior art, including a battery box lower cavity, a battery box upper cover, and a plurality of battery cells; the plurality of battery cells are arranged in series and parallel in the battery box lower cavity, the battery box upper cover is fastened to the battery box lower cavity by screws, and after the plurality of battery cells are connected in series and parallel, the gaps between the battery cells and the gaps between the battery box lower cavity and the battery box upper cover form a flow channel, the flow channel is a pipe network type, the cooling medium flows in the flow channel, and the cooling medium adopts a fluorinated liquid;

[0007] Preferably, the lower cavity of the battery box and the upper cover of the battery box are sealed by a sealing strip to meet the IP68 sealing requirements to form an IP68 sealed battery box;

[0008] Preferably, the external power and control terminals on the IP68 sealed battery box meet the IP68 sealing requirements after installation;

[0009] Preferably, a cooling medium inlet and a cooling medium outlet are provided on the lower cavity of the battery box, and the cooling medium inlet and the cooling medium outlet are respectively located on both sides of one side of the lower cavity of the battery box;

[0010] Preferably, the cooling medium is driven by a pump to flow in the flow channel;

[0011] Preferably, the spacing between the fixing screws of the lower cavity of the battery box and the upper cover of the battery box is ≤100mm;

[0012] Preferably, the battery box lower cavity and the battery box upper cover are formed by die-casting aluminum alloy, or by welding aluminum alloy plates or sheet metal welding;

[0013] Preferably, the sealing strip has two layers;

[0014] Preferably, the model of the fluorinated liquid is "3M Novec 7100".

[0015] The immersion liquid-cooled battery module provided by the utility model is subjected to a thermal simulation experiment, and the simulation results show that the method provided by the utility model effectively reduces the temperature of the battery core and makes the temperature difference between each battery core very small.

[0016] Compared with the prior art, the positive effects of the utility model are: the immersion liquid-cooled battery module in the utility model can effectively dissipate heat and maintain uniform temperature for each battery cell, thereby increasing the battery life and reducing the risk of thermal runaway of the battery. At the same time, the non-flammable cooling medium is an excellent firefighting medium, which also isolates the contact between oxygen and the battery cell, so that the battery cell is always in a firefighting environment, greatly improving firefighting safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the separation of the immersion liquid-cooled battery module in the utility model;

[0018] Figure 2 It is a schematic diagram of the internal structure of the immersion liquid-cooled battery module in the utility model;

[0019] Figure 3 It is a schematic cross-sectional top view of the flow channel of the immersion liquid-cooled battery module in the present invention;

[0020] Figure 4 It is a schematic cross-sectional side view of the flow channel of the immersion liquid-cooled battery module in the present invention;

[0021] Figure 5The temperature field on the upper surface of the battery cell in the thermal simulation result of the immersion liquid-cooled battery module in the utility model;

[0022] The markings in the accompanying drawings are: 1-lower cavity of the battery box, 2-upper cover of the battery box, 3-battery cell, 4-cooling medium inlet, 5-cooling medium outlet, 6-sealing strip, 7-power and control terminals, 8-cooling medium, 9-flow channel, 10-screw. DETAILED DESCRIPTION

[0023] Combine the following Figure 1-5 The utility model is further described with specific implementation methods.

[0024] See attached Figure 1-5 The utility model is conceived to provide an immersion liquid-cooled battery module, including a battery box lower cavity 1, a battery box upper cover 2, and a plurality of battery cells 3; the plurality of battery cells 3 are arranged in series and parallel in the battery box lower cavity 1, and the battery box upper cover 2 is fastened and installed on the battery box lower cavity 1 by screws 10. After the plurality of battery cells 3 are connected in series and parallel, the gaps between the battery cells and the gaps between the battery box lower cavity 1 and the battery box upper cover 2 form a flow channel, and the flow channel is a pipe network type, and a cooling medium flows in the flow channel, and the cooling medium adopts a fluorinated liquid;

[0025] The lower cavity 1 of the battery box and the upper cover 2 of the battery box are sealed by two layers of rubber strips and fastened with tightly arranged screws 10 to meet the IP68 sealing requirements and form an IP68 sealed battery box. The external power and control terminals 7 installed on the battery box meet the IP68 sealing requirements after installation. The IP68 seal allows the cooling medium 8 to flow in the internal flow channel 9 of the box without leakage;

[0026] After several battery cells 3 are connected in series and in parallel, the gaps between the battery cells and the gaps between the lower cavity 1 and the upper cover 2 of the battery box form a flow channel, and the flow channel is a pipe network type. The cooling medium flows in the flow channel under the action of the pump, and the cooling medium is in direct contact with the battery cells without additional thermal resistance in the middle. Moreover, the six sides of each battery cell can fully contact with the cooling medium for heat exchange, making the heat exchange efficiency higher. At the same time, the pipe network flow channel has a small pressure loss, and a smaller power water pump can be selected. The flow distribution of the pipe network flow channel is uniform, which can make the temperature consistency of each battery cell better;

[0027] The lower cavity 1 of the battery box is provided with a cooling medium inlet 4 and a cooling medium outlet 5, and the cooling medium inlet 4 and the cooling medium outlet 5 are respectively located on both sides of one side of the lower cavity 1 of the battery box;

[0028] The spacing between the fixing screws of the lower cavity 1 of the battery box and the upper cover 2 of the battery box is ≤100mm;

[0029] The battery box lower cavity 1 and the battery box upper cover 2 are formed by die-casting aluminum alloy, or by welding aluminum alloy plates or sheet metal welding;

[0030] Alternatively, the flow channel is composed of gaps between the battery cells and gaps between the battery cells and the left and right and top and bottom of the battery box to form a pipe network flow channel.

[0031] The cooling medium uses fluorinated liquid, which has the characteristics of high insulation, high non-flammability, high thermal conductivity, low viscosity, etc. It is also an excellent fire-fighting medium as a cooling medium; compared with transformer oil, fluorinated liquid has the advantages of low viscosity and non-flammability. Preferably, the model of fluorinated liquid is "3M Novec 7100", and the physical properties are shown in Table 1, which is a physical property parameter table of "3M Novec7100".

[0032] Table 1

[0033]

[0034]

[0035] The utility model implements an immersion liquid-cooled battery module. Through thermal simulation experiments, simulation results show that the method provided by the utility model effectively reduces the temperature of the battery cell and makes the temperature difference between each battery cell very small. The simulation input parameters are shown in Table 2, which is a thermal simulation input parameter table.

[0036] Table 2

[0037]

[0038] The simulation results are shown in Table 3 and Figure 5 As shown, Table 3 is a thermal simulation result table.

[0039] Table 3

[0040]

[0041] Compared with the prior art, the positive effects of the utility model are: the immersion liquid-cooled battery module in the utility model can effectively dissipate heat and maintain uniform temperature for each battery cell, thereby increasing the battery life and reducing the risk of thermal runaway of the battery. At the same time, the non-flammable cooling medium is an excellent firefighting medium, and also isolates the contact between oxygen and the battery cell, so that the battery cell is always in a firefighting environment, greatly improving firefighting safety.

[0042] In summary, the above only embodies the preferred technical solution of the present utility model. Any changes that may be made to certain parts thereof by those skilled in the art all embody the principles of the present utility model and should all be within the technical scope of the present utility model.

Claims

1. An immersion liquid-cooled battery module, characterized in that: It comprises a battery box lower cavity (1), a battery box upper cover (2), and a plurality of battery cells (3); A plurality of battery cells (3) are arranged in series and parallel in a lower cavity (1) of a battery box. The upper cover plate (2) of the battery box is fastened to the lower cavity (1) of the battery box by means of screws (10). After the plurality of battery cells (3) are connected in series and parallel, gaps between the battery cells and gaps between the lower cavity (1) of the battery box and the upper cover plate (2) of the battery box form a flow channel. The flow channel is of a pipe network type. A cooling medium flows in the flow channel. The cooling medium uses a fluorinated liquid.

2. An immersion liquid-cooled battery module as claimed in claim 1, characterized in that: The battery box lower cavity (1) and the battery box upper cover (2) are sealed by a sealing strip to meet IP68 sealing requirements to form an IP68 sealed battery box.

3. An immersion liquid-cooled battery module as claimed in claim 2, characterized in that: The external power and control terminals (7) on the IP68 sealed battery box meet the IP68 sealing requirements after installation.

4. An immersion liquid-cooled battery module as claimed in claim 3, characterized in that: The lower cavity (1) of the battery box is provided with a cooling medium inlet (4) and a cooling medium outlet (5), and the cooling medium inlet (4) and the cooling medium outlet (5) are respectively located on both sides of a side surface of the lower cavity (1) of the battery box.

5. An immersion liquid-cooled battery module as claimed in claim 2, characterized in that: The cooling medium is driven by a pump to flow in the flow channel.

6. An immersion liquid-cooled battery module as claimed in claim 2, characterized in that: The spacing between the fixing screws of the battery box lower cavity (1) and the battery box upper cover (2) is ≤100 mm.

7. An immersion liquid-cooled battery module as claimed in claim 6, characterized in that: The battery box lower cavity (1) and the battery box upper cover plate (2) are formed by die-casting aluminum alloy, or by welding aluminum alloy plates or sheet metal welding.

8. An immersion liquid-cooled battery module as claimed in claim 2, characterized in that: The sealing strip has two layers.

9. The immersion liquid-cooled battery module according to claim 1, characterized in that: The model of fluorinated liquid is "3MNovec 7100".

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