Pump driving and compression cycle coupled direct expansion cooling system

Abstract

The utility model discloses a pump drive and compression cycle coupled direct expansion cooling system, which relates to the technical field of equipment cooling and comprises a cooling coil and a condenser, the cooling coil is in contact fit with a battery pack in a battery pack, and a closed circulation path is formed between the cooling coil and the condenser through a connecting pipeline. The first driving loop and the second driving loop are connected to the circulation path in series, and one of the first driving loop and the second driving loop is selected for use. According to the utility model, the two driving loops are additionally arranged on the circulation path formed by the cooling coil and the condenser, one of the two driving loops is selected for use, and the two driving loops can be used for respectively dealing with a conventional battery pack cooling condition and an abnormal battery pack cooling condition, so that the battery pack can be quickly cooled under the abnormal condition; meanwhile, due to the arrangement of the two driving loops, the two driving loops can be selectively used under corresponding working conditions, energy loss is avoided, and cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of equipment cooling, in particular to a direct expansion cooling system coupled with pump drive and compression cycle. Background Art

[0002] A battery pack is an integral unit assembled from multiple battery modules and is used to store and provide electrical energy. It is a higher-level component in a battery system and is typically composed of several battery modules, connectors, a battery management system (BMS), a cooling system, electrical interfaces, and a casing. The main function of a battery pack is to integrate multiple battery modules into a single unit. Battery modules are connected in parallel or series to increase the voltage, capacity, or power of the battery system. Since operating temperature affects the internal resistance, heat rate, discharge capacity, cycle life, and state consistency of the battery, if the operating temperature of the battery pack is too high or too low, the cycle life of the battery pack will drop rapidly. Therefore, the operating temperature of the battery pack needs to be controlled within a reasonable range.

[0003] At present, cooling coils are generally used to cool the battery packs inside the battery pack. Specifically, the delivery pump, cooling plate and condenser tube are connected in series through connecting pipes to form a circulating path. The battery packs in the battery pack are in contact with the cooling coils. When the battery pack is working normally, the delivery pump is used to deliver the liquid refrigerant in the pipe to the cooling coil. The battery packs in the battery pack are in contact with the cooling coil for heat exchange and cooling. The gaseous refrigerant in the cooling coil is then delivered to the condenser, where it is cooled and becomes liquid, thus completing the cooling cycle.

[0004] However, during the above-mentioned cooling cycle, when the delivery pump acts as a driving source to deliver the gaseous refrigerant to the condenser, the delivery pump only serves the purpose of delivering the gaseous refrigerant and cannot exert a pressurizing effect on the gaseous refrigerant. Furthermore, when the battery pack experiences abnormal conditions such as a large amount of heat release, the internal pressure of the connecting pipe between the cooling coil and the condenser is relatively low, and the gaseous refrigerant output through the cooling coil cannot be well dissipated at the condenser, that is, the heat dissipation effect is poor, making it impossible to control the abnormal conditions of the battery pack, and ultimately causing thermal runaway.

[0005] To this end, we propose a direct expansion cooling system that couples pump drive with compression cycle to solve the above problems. Utility Model Content

[0006] The purpose of the present utility model is to solve the problems in the prior art and to propose a direct expansion cooling system coupled with a pump drive and a compression cycle. The cooling system can select a corresponding driving source according to the corresponding working conditions to drive the refrigerant in the circulation path to flow, so as to achieve corresponding cooling effects under different working conditions.

[0007] In order to solve the above problems, the present invention provides the following technical solutions:

[0008] A pump-driven and compression cycle-coupled direct expansion cooling system includes a cooling coil and a condenser arranged in contact with a battery group in a battery pack, and a connecting pipe forms a closed circulation path between the cooling coil and the condenser. The system also includes a first drive circuit and a second drive circuit connected in series to the circulation path, wherein the first drive circuit is composed of a parallel delivery pump and a first side pipe, and the second drive circuit is composed of a parallel boost drive source and a second side pipe; the first path formed by the delivery pump and the second side pipe and the second path formed by the boost drive source and the first side pipe are selectively connected.

[0009] As a further solution of the present invention: the boost driving source includes a compressor, and the connection between the delivery pump and the first branch pipeline, as well as between the compressor and the second branch pipeline, are connected to the circulation path through three-way valves.

[0010] As a further solution of the present invention: the boost drive source also includes a gas-liquid separator, which is connected in series to the circulation path formed by the compressor, condenser, first side branch pipe and cooling coil, and the gas-liquid separator is respectively connected to the outlet of the cooling coil and the inlet of the compressor.

[0011] As a further solution of the present invention: a refrigerant distributor and a refrigerant collector are provided on the circulation passage, and the refrigerant distributor and the refrigerant collector are respectively connected to the inlet and outlet of the cooling coil.

[0012] As a further solution of the utility model: it also includes a gas storage pressure regulating tank, which is connected in parallel to the circulation path formed by the delivery pump, the cooling coil, the second side pipe and the condenser, and the gas storage pressure regulating tank and the cooling coil are arranged in parallel.

[0013] As a further solution of the present invention: a liquid reservoir is connected to the circulation path, and the liquid reservoir is respectively connected to the outlet of the condenser and the inlet of the cooling coil.

[0014] As a further solution of the present invention: a capillary supercooling tube is connected to the circulation passage, and the capillary supercooling tube is respectively connected to the outlet of the condenser and the inlet of the cooling coil.

[0015] As a further solution of the present invention: a through hole is opened on the pipe of the cooling coil located in the battery pack, and a control valve for opening and closing the through hole is provided on the cooling coil.

[0016] As a further solution of the present invention: the through holes are provided in plurality and are respectively arranged at the corners of the battery pack.

[0017] As a further solution of the present invention: the inlet and outlet of the cooling coil are both provided with electric valves for controlling the opening and closing thereof.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. By adding two drive circuits to the circulation path formed by the cooling coil and condenser, the two drive circuits can be used selectively. The two drive circuits can respectively cope with normal battery pack cooling conditions and abnormal battery pack cooling conditions, ensuring that the battery pack can be cooled quickly under abnormal conditions. At the same time, the two drive circuits can be used selectively under corresponding working conditions, avoiding energy loss and reducing costs.

[0020] 2. By setting the boost drive source, when the battery pack reaches the set temperature under abnormal conditions, the boost drive source in the second drive circuit can be selected to pressurize the refrigerant in the circulation path and drive it to flow. After the refrigerant is pressurized, the condenser can better cool it, making the refrigerant temperature in the entire circulation path lower. As a result, the refrigerant in the cooling coil can absorb more heat from the battery pack, achieving a better cooling effect.

[0021] 3. By setting the control valve, through-hole and electric valve, when the battery pack has thermal runaway, the electric valve closes the inlet and outlet of the cooling coil. At this time, the refrigerant inside the cooling coil will be temporarily stored. At the same time, the control valve is used to open the through-hole. Since the refrigerant inside the cooling coil will be heated and vaporized, the gaseous refrigerant will be sprayed from the through-hole to the surroundings of the battery pack, isolating the battery pack from oxygen and preventing further deterioration of the thermal runaway phenomenon. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below with reference to the accompanying drawings.

[0023] Figure 1 It is a structural diagram of the utility model;

[0024] Figure 2 This is a schematic diagram of the top view of the cooling coil and battery pack in the present invention;

[0025] Figure 3 yes Figure 2Schematic diagram of the top view of the battery pack with a built-in battery pack in the state.

[0026] In the figure: 1. Cooling coil; 2. Condenser; 3. Connecting pipe; 4. Delivery pump; 5. Compressor; 6. Three-way valve; 7. Gas-liquid separator; 8. Control valve; 9. Refrigerant distributor; 10. Refrigerant collector; 11. Gas pressure regulating tank; 12. Liquid storage tank; 13. Capillary subcooling tube; 14. Electric valve; 15. First side branch pipe; 16. Second side branch pipe; a. Battery pack; b. Battery group. DETAILED DESCRIPTION

[0027] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0028] like Figure 1-Figure 3 As shown, a pump-driven and compression cycle coupled direct expansion cooling system includes a cooling coil 1 and a condenser 2. The cooling coil 1 is arranged in the battery pack a and is in contact with the battery group b inside the battery pack a. A closed circulation path is formed between the cooling coil 1 and the condenser 2 through a connecting pipe 3. Liquid refrigerant is stored in the circulation path. At the same time, a driving source for driving the refrigerant to flow is provided on the circulation path. When the liquid refrigerant flows into the cooling coil 1, the battery group b inside the battery pack a is cooled by heat transfer. In this process, part of the liquid refrigerant will become gaseous, and then the liquid and gaseous refrigerants will be circulated to the condenser 2, and then recycled again after being processed by the condenser 2.

[0029] When the battery pack a releases heat abnormally, the above-mentioned cooling means cannot meet the cooling requirements. Based on this, the utility model is further provided with a boost drive source. The drive source and the boost drive source constitute the first passage and the second passage respectively. The first passage and the second passage are used selectively to deal with normal cooling conditions and abnormal cooling conditions respectively.

[0030] Specifically, a first drive circuit and a second drive circuit are connected in series in the circulation path. The first drive circuit consists of a parallel delivery pump 4 and a first branch pipe 15, that is, the conventional drive source described above is set as the delivery pump 4. The second drive circuit consists of a parallel boost drive source and a second branch pipe 16. The delivery pump 4 and the second branch pipe 16 form the first path described above, and the boost drive source and the first branch pipe 15 form the second path described above. When battery pack a reaches a set temperature, the boost drive source in the second drive circuit can be selected to pressurize the refrigerant in the circulation path and drive it to flow. After the refrigerant is pressurized, the condenser 2 can better cool it, reducing the refrigerant temperature throughout the circulation path. The refrigerant in the cooling coil 1 can then absorb more heat from the battery pack a, achieving a better cooling effect and addressing abnormal heat release from the battery pack a.

[0031] For the setting of the above-mentioned medium-pressure driving source, the boost driving source includes a compressor 5 and a gas-liquid separator 7, and the delivery pump 4 and the first side branch pipe 15, as well as the compressor 5 and the second side branch pipe 16 are connected to the circulation path through the three-way valve 6; the gas-liquid separator 7 is connected in series to the circulation path formed by the compressor 5, the condenser 2, the first side branch pipe 15 and the cooling coil 1, and the gas-liquid separator 7 is respectively connected to the outlet of the cooling coil 1 and the inlet of the compressor 5.

[0032] In the circulation path formed by the delivery pump 4, the cooling coil 1, the second side branch pipe 16 and the condenser 2, in order to prevent the refrigerant from having poor fluidity during the process of flowing from the cooling coil 1 to the condenser 2, the utility model is further provided with a gas storage pressure regulating tank 11, and the gas storage pressure regulating tank 11 is connected in parallel to the circulation path formed by the delivery pump 4, the cooling coil 1, the second side branch pipe 16 and the condenser 2, and the gas storage pressure regulating tank 11 is arranged in parallel with the cooling coil 1.

[0033] Furthermore, a liquid reservoir 12 is connected to the circulation path, and the liquid reservoir 12 is respectively connected to the outlet of the condenser 2 and the inlet of the cooling coil 1; at the same time, a capillary supercooling tube 13 is also connected to the circulation path, and the capillary supercooling tube 13 is respectively connected to the outlet of the condenser 2 and the inlet of the cooling coil 1.

[0034] To allow the present invention to simultaneously cool a large number of battery packs a, a refrigerant distributor 9 and a refrigerant collector 10 are provided in the circulation path, and the refrigerant distributor 9 and the refrigerant collector 10 are respectively connected to the inlet and outlet of the cooling coil 1. The refrigerant distributor 9 is equivalent to a component consisting of a main pipe and multiple branch pipes connected thereto, and the multiple branch pipes are respectively connected to the inlets of multiple cooling coils 1. The refrigerant collector 10 has the same structure as the refrigerant distributor 9, except that the multiple branch pipes in the refrigerant collector 10 are respectively connected to the outlets of multiple cooling coils 1. With this arrangement, refrigerant can be distributed to cool multiple battery packs a.

[0035] like Figure 2-Figure 3 As shown, further, when the compressor 5 is provided to deal with the abnormal heat release of the battery pack a, if the battery pack a further deteriorates under the abnormal heat release and thermal runaway occurs, it is necessary to extinguish the fire of the battery pack a. To this end, the present invention provides the following measures for this situation:

[0036] (1) A through hole is opened on the pipe of the cooling coil 1 located inside the battery pack a, and a control valve 8 for opening and closing the through hole is provided on the cooling coil 1. A plurality of through holes are provided and arranged at the corners of the battery pack a respectively;

[0037] (2) The inlet and outlet of the cooling coil 1 are both provided with electric valves 14 for controlling the opening and closing thereof.

[0038] When thermal runaway occurs, the electric valve 14 closes the inlet and outlet of the cooling coil 1. At this time, the refrigerant inside the cooling coil 1 will be temporarily stored. At the same time, the control valve 8 is used to open the through hole. Since the refrigerant inside the cooling coil 1 will be heated and vaporized, the gaseous refrigerant will be sprayed from the through hole to the surroundings of the battery pack b, isolating the oxygen around the battery pack b and preventing further deterioration of the thermal runaway phenomenon.

[0039] The above describes an embodiment of the present invention in detail. However, the above content is only a preferred embodiment of the present invention and should not be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent application of the present invention.

Claims

1. A direct expansion cooling system coupled with a pump drive and compression cycle, characterized in that: The invention comprises a cooling coil (1) and a condenser (2) arranged in contact with a battery pack (b) in a battery pack (a), wherein a closed circulation path is formed between the cooling coil (1) and the condenser (2) via a connecting pipe (3), and further comprises a first drive circuit and a second drive circuit connected in series to the circulation path, wherein the first drive circuit is composed of a parallel delivery pump (4) and a first branch pipe (15); and a first path formed by the delivery pump (4) and the second branch pipe (16) and a second path formed by a boost drive source and the first branch pipe (15) are selectively connected.

2. A direct expansion cooling system coupled with pump drive and compression cycle according to claim 1, characterized in that: The boost drive source includes a compressor (5), and the connection between the delivery pump (4) and the first branch pipe (15), as well as the connection between the compressor (5) and the second branch pipe (16) are both connected to the circulation path through a three-way valve (6).

3. A direct expansion cooling system coupled with pump drive and compression cycle according to claim 2, characterized in that: The boost drive source further includes a gas-liquid separator (7), which is connected in series to a circulation path formed by the compressor (5), the condenser (2), the first branch pipe (15) and the cooling coil (1), and the gas-liquid separator (7) is respectively connected to the outlet of the cooling coil (1) and the inlet of the compressor (5).

4. The direct expansion cooling system coupled with pump drive and compression cycle according to claim 1, characterized in that: A refrigerant distributor (9) and a refrigerant collector (10) are provided on the circulation passage, and the refrigerant distributor (9) and the refrigerant collector (10) are respectively connected to the inlet and outlet of the cooling coil (1).

5. The direct expansion cooling system coupled with pump drive and compression cycle according to claim 1, characterized in that: The invention also includes a gas storage and pressure regulating tank (11), which is connected in parallel to a circulation path formed by a delivery pump (4), a cooling coil (1), a second branch pipe (16) and a condenser (2), and the gas storage and pressure regulating tank (11) and the cooling coil (1) are arranged in parallel.

6. The direct expansion cooling system coupled with pump drive and compression cycle according to claim 1, characterized in that: A liquid reservoir (12) is connected to the circulation passage, and the liquid reservoir (12) is respectively connected to the outlet of the condenser (2) and the inlet of the cooling coil (1).

7. The direct expansion cooling system coupled with pump drive and compression cycle according to claim 1, characterized in that: A capillary supercooling tube (13) is connected to the circulation passage, and the capillary supercooling tube (13) is respectively connected to the outlet of the condenser (2) and the inlet of the cooling coil (1).

8. A direct expansion cooling system coupled with a pump drive and compression cycle according to any one of claims 1 to 7, characterized in that: The cooling coil (1) is provided with a through hole on a pipe located in the battery pack (a), and a control valve (8) for opening and closing the through hole is provided on the cooling coil (1).

9. The direct expansion cooling system coupled with pump drive and compression cycle according to claim 8, characterized in that: The through holes are provided in plurality and are respectively arranged at the corners of the battery pack (a).

10. A direct expansion cooling system coupled with pump drive and compression cycle according to claim 9, characterized in that: The inlet and outlet of the cooling coil (1) are both provided with electric valves (14) for controlling the opening and closing thereof.

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