Battery pack and liquid leakage protection method

Abstract

The invention relates to a battery pack and a liquid leakage protection method. The battery pack comprises a battery module; the liquid cooling assembly comprises a liquid cooling plate, a liquid inlet pipe, a pressure sensor and a first control valve; the battery module is arranged on the liquid cooling plate, the liquid inlet pipe is communicated with a liquid inlet of the liquid cooling plate, the pressure sensor and the first control valve are both mounted on the liquid inlet pipe, the pressure sensor is used for detecting the pressure in the liquid inlet pipe, and the first control valve is used for controlling the liquid inlet pipe to be connected or disconnected; the liquid collecting piece is provided with a flow collecting groove distributed around the peripheral edge of the liquid cooling plate, and the flow collecting groove is used for collecting leaked liquid; the insulation resistance sensor is arranged in the current collecting groove and is used for detecting the resistance of the position where the insulation resistance sensor is located; the battery management system is electrically connected with the pressure sensor, the first control valve and the insulation resistance sensor; the battery management system is used for controlling the liquid inlet pipe to be cut off through the first control valve according to detection results of the insulation resistance sensor and the pressure sensor.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a battery pack and a leakage protection method. Background Art

[0002] As a key component of new energy vehicles, the performance of power batteries directly affects the overall performance of new energy vehicles. The safety, consistency, high and low temperature performance, life and cost of power batteries are the main indicators of battery performance. In order to ensure the above performance of power batteries, power batteries need to adopt a liquid cooling solution to achieve temperature control. At present, the coolant used in the liquid cooling solution is ethylene glycol + water, which is conductive. Therefore, once the liquid cooling system leaks, it is very likely to cause a battery short circuit and cause thermal runaway. In the prior art, once leakage is detected in the battery pack, the liquid cooling system is immediately cut off.

[0003] However, leakage from the liquid cooling system is not the only source of liquid in the battery pack. It may also be condensation or liquid entering from the outside. Blindly cutting off the liquid cooling system will also cause the heat dissipation performance of the battery pack to drop sharply, and there is also a risk of causing thermal runaway. Summary of the invention

[0004] Based on this, it is necessary to provide a battery pack and leakage protection method to improve the above defects, in order to address the problem that blindly cutting off the liquid cooling system in the prior art will cause the heat dissipation performance of the battery pack to drop sharply and also pose a risk of thermal runaway.

[0005] A battery pack, comprising:

[0006] Battery module;

[0007] A liquid cooling assembly, comprising a liquid cooling plate, a liquid inlet pipe, a pressure sensor and a first control valve; the battery module is arranged on the liquid cooling plate, the liquid inlet pipe is connected to the liquid inlet of the liquid cooling plate, the pressure sensor and the first control valve are both installed on the liquid inlet pipe, the pressure sensor is used to detect the pressure in the liquid inlet pipe, and the first control valve is used to control the liquid inlet pipe to be turned on or off;

[0008] A liquid collecting member, comprising a collecting groove arranged around the peripheral edge of the liquid cooling plate, wherein the collecting groove is used to collect leaked liquid;

[0009] An insulation resistance sensor, disposed in the collecting tank, for detecting the resistance at the location;

[0010] A battery management system is electrically connected to the pressure sensor, the first control valve and the insulation resistance sensor; the battery management system is used to control the liquid inlet pipe to be cut off through the first control valve according to the detection results of the insulation resistance sensor and the pressure sensor.

[0011] In one of the embodiments, the surface of the liquid cooling plate on one side facing the battery module has a cooling area and a peripheral area arranged around the cooling area; the battery module is arranged in the cooling area, the liquid collecting piece is arranged in the peripheral area, and the collecting groove is opened on the side of the liquid collecting piece away from the liquid cooling plate.

[0012] In one embodiment, the liquid collecting member further has a first drainage slope located outside the collecting groove, the first drainage slope is arranged around the collecting groove, the inner side of the first drainage slope relative to the liquid cooling plate is a first inner side height, the outer side of the first drainage slope relative to the liquid cooling plate is a first outer side height, and the first outer side height is greater than the first inner side height;

[0013] The liquid collecting part also has a second drainage slope located between the collecting groove and the battery module, the second drainage slope is arranged around the battery module, the inner side of the second drainage slope has a second inner height relative to the liquid cooling plate, the outer side of the second drainage slope has a second outer height relative to the liquid cooling plate, and the second inner height is greater than the second outer height.

[0014] In one embodiment, the liquid collecting member further comprises a first drainage groove and a first avoidance hole, wherein the first drainage groove is disposed on the second drainage slope and is connected to the collecting groove, and the first avoidance hole is located in the first drainage groove and penetrates from the first drainage groove to a side of the liquid collecting member facing the liquid cooling plate;

[0015] One end of the liquid inlet pipe passes through the first avoidance hole and is connected to the liquid inlet of the liquid cooling plate. The insulation resistance sensor is arranged in the first drainage groove.

[0016] In one of the embodiments, the battery pack further includes a first drain valve, a first liquid level sensor, a second drain valve, and a second liquid level sensor, all of which are electrically connected to the battery management system;

[0017] The two ends of the liquid collecting member in the preset direction are respectively a first end and a second end, the first liquid discharge valve is communicated with the portion of the manifold located at the first end, and the second liquid discharge valve is communicated with the portion of the manifold located at the second end; the first liquid level sensor is installed in the manifold and located at the first end, and the second liquid level sensor is installed in the manifold and located at the second end;

[0018] The battery management system is used to control the first drain valve to be opened or closed according to the detection result of the first liquid level sensor, and is also used to control the second drain valve to be opened or closed according to the detection result of the second liquid level sensor.

[0019] In one embodiment, a leakage protection method for a battery pack as described in any of the above embodiments comprises the following steps:

[0020] The insulation resistance sensor monitors the resistance at the location in real time, and the pressure sensor monitors the pressure in the liquid inlet pipe in real time;

[0021] If the resistance value detected by the insulation resistance sensor is less than a preset resistance value, and the pressure detected by the pressure sensor is less than a preset pressure, the battery management system controls the liquid inlet pipe to be cut off through the first control valve.

[0022] In one embodiment, the first liquid level sensor and the second liquid level sensor respectively monitor the liquid level height at their respective locations in real time;

[0023] After the step of the first control valve controlling the liquid inlet pipe to be cut off, the following step further comprises:

[0024] If the liquid level detected by at least one of the first liquid level sensor and the second liquid level sensor is greater than a first preset liquid level, the battery management system controls the relay to be disconnected.

[0025] In one embodiment, after the step of controlling the relay to be disconnected, the battery management system further comprises:

[0026] The battery management system controls the first drain valve and / or the second drain valve to open;

[0027] If the liquid levels detected by the first liquid level sensor and the second liquid level sensor are both lower than the first preset liquid level, the battery management system controls the relay to close;

[0028] If the liquid level detected by the first liquid level sensor is lower than a second preset liquid level, the battery management system controls the first drain valve to be cut off; wherein the second preset liquid level is lower than the first preset liquid level;

[0029] If the liquid level detected by the second liquid level sensor is lower than the second preset liquid level, the battery management system controls the second drain valve to be cut off.

[0030] In one embodiment, after the step of the battery management system controlling the relay to be disconnected, the method further includes:

[0031] If the liquid level detected by the first liquid level sensor is greater than or equal to a first preset liquid level, and the liquid level detected by the second liquid level sensor is less than the first preset liquid level, the battery management system controls the first drain valve to open;

[0032] If the liquid level detected by the second liquid level sensor is greater than or equal to a second preset liquid level, the battery management system controls the second drain valve to open; wherein the second preset liquid level is less than the first preset liquid level;

[0033] If the liquid levels detected by the first liquid level sensor and the second liquid level sensor are both lower than the first preset liquid level, the battery management system controls the relay to close;

[0034] If the liquid level detected by the first liquid level sensor is lower than the second preset liquid level, the battery management system controls the first drain valve to be closed;

[0035] If the liquid level detected by the second liquid level sensor is lower than the second preset liquid level, the battery management system controls the second drain valve to be cut off.

[0036] In one embodiment, after the step of the battery management system controlling the relay to be disconnected, the method further includes:

[0037] If the liquid level detected by the second liquid level sensor is greater than or equal to the first preset liquid level, and the liquid level detected by the first liquid level sensor is less than the first preset liquid level, the battery management system controls the second drain valve to open;

[0038] If the liquid level detected by the first liquid level sensor is greater than or equal to a second preset liquid level, the battery management system controls the first drain valve to open; wherein the second preset liquid level is less than the first preset liquid level.

[0039] In the above-mentioned battery pack and leakage protection method, the battery management system determines whether there is leakage through the detection result of the insulation resistance sensor, and when there is leakage, it uses the detection result of the pressure sensor to determine whether the leakage is leaked coolant. Only when it is determined that the leakage in the collecting tank is leaked coolant, the battery management system controls the liquid inlet pipe to be cut off through the first control valve, thereby avoiding blindly closing the liquid inlet pipe and stopping cooling the battery module, reducing the risk of thermal runaway of the battery module. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 An exploded view of a battery pack in one embodiment of the present invention;

[0041] Figure 2 for Figure 1 A top view of the battery pack shown (with the cover omitted);

[0042] Figure 3 for Figure 1 A schematic diagram of the assembly structure of the liquid collecting part of the battery pack and various sensors and other components shown;

[0043] Figure 4 for Figure 3 A top view of the liquid collecting member shown;

[0044] Figure 5 It is a flowchart of the steps of the liquid leakage protection method in the first embodiment of the present invention;

[0045] Figure 6 for Figure 5 Flow chart of the leakage protection method shown;

[0046] Figure 7 A flowchart of a liquid leakage protection method according to a second embodiment of the present invention;

[0047] Figure 8 It is a flowchart of the steps of the liquid leakage protection method in the third embodiment of the present invention;

[0048] Fig. 9 for Figure 7 In the second embodiment shown Figure 8 A flow chart of the liquid leakage protection method in the third embodiment;

[0049] Fig.10 It is a flowchart of the steps of the liquid leakage protection method in the fourth embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0051] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0052] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0053] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it 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, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0054] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0055] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0056] See also Figures 1 to 4 As shown, an embodiment of the present invention provides a battery pack, including a box body 81 and a battery module 10, a liquid cooling assembly (not shown), a liquid collecting part 30, an insulation resistance sensor 40 and a battery management system 50, all of which are arranged in the box body 81. The liquid cooling assembly includes a liquid cooling plate 21, a liquid inlet pipe 22, a pressure sensor 23, a first control valve 24 and a liquid outlet pipe 25. The battery module 10 is arranged on the liquid cooling plate 21. Optionally, a thermal conductive adhesive is filled between the liquid cooling plate 21 and the battery module 10. The thermal conductive adhesive is used to achieve a fixed connection and heat conduction between the liquid cooling plate 21 and the battery module 10, thereby improving the cooling effect of the liquid cooling plate 21 on the battery module 10. One end of the liquid inlet pipe 22 is connected to the liquid inlet 211 of the liquid cooling plate 21, and the other end of the liquid inlet pipe 22 passes out of the box body 81 and is connected to an external pipeline. One end of the liquid outlet pipe 25 is connected to the liquid outlet 213 of the liquid cooling plate 21, and the other end of the liquid outlet pipe 25 passes through the outside of the box 81 and is connected to the external pipeline. The coolant enters the liquid cooling plate 21 through the liquid inlet pipe 22, and cools the battery module 10 in the liquid cooling plate 21. The coolant in the liquid cooling plate 21 is then discharged from the liquid outlet pipe 25, thereby taking away the heat of the battery module 10 to avoid the battery module 10 from being overheated. The pressure sensor 23 and the first control valve 24 are both installed on the liquid inlet pipe 22. The pressure sensor 23 is used to detect the pressure in the liquid inlet pipe 22, and the first control valve 24 is used to control the conduction or cutoff of the liquid inlet pipe 22. When the first control valve 24 controls the conduction of the liquid inlet pipe 22, the coolant can enter the liquid cooling plate 21 through the liquid inlet pipe 22; when the first control valve 24 controls the cutoff of the liquid inlet pipe 22, the coolant stops entering the liquid cooling plate 21 through the liquid inlet pipe 22.

[0057] refer to Figure 2 , Figure 3 and Figure 4As shown, the liquid collecting part 30 has a collecting groove 31 arranged around the peripheral edge of the liquid cooling plate 21, and the collecting groove 31 surrounds the battery module 10, and the collecting groove 31 is used to collect leaked liquid. The insulation resistance sensor 40 is arranged in the collecting groove 31 of the liquid collecting part 30, and is used to detect the resistance at the location. When leakage occurs in the battery pack, the leaked liquid is collected in the collecting groove 31. Since the leaked liquid can be conductive, when the insulation resistance sensor 40 detects that the resistance value in the collecting groove 31 decreases (for example, when the insulation resistance sensor 40 detects that the resistance value in the collecting groove 31 is lower than a preset resistance value), it can be determined that there is leakage. The battery management system 50 is electrically connected to the pressure sensor 23, the first control valve 24 and the insulation resistance sensor 40 through a wiring harness. The battery management system 50 is used to control the liquid inlet pipe 22 to be cut off through the first control valve 24 according to the detection results of the insulation resistance sensor 40 and the pressure sensor 23.

[0058] During actual use of the battery pack, the first control valve 24 controls the liquid inlet pipe 22 to be in a conducting state, and the coolant enters the liquid cooling plate 21 through the liquid inlet pipe 22 and is discharged from the liquid outlet pipe 25. The coolant flowing through the liquid cooling plate 21 takes away the heat of the battery module 10, that is, the battery module 10 is cooled. At the same time, the insulation resistance sensor 40 monitors the resistance in the manifold 31 in real time, and the pressure sensor 23 monitors the pressure in the liquid inlet pipe 22 in real time.

[0059] If the insulation resistance sensor 40 detects that the resistance value in the manifold 31 is less than a preset resistance value, and the pressure sensor 23 detects that the pressure value in the liquid inlet pipe 22 is greater than or equal to a preset pressure value, it indicates that there is leakage in the manifold 31, but the leakage is not cooling liquid. At this time, it is necessary to keep the cooling liquid entering the liquid cooling plate 21, that is, it is necessary to keep cooling the battery module 10 to avoid the battery module 10 from being overheated and causing a thermal runaway accident.

[0060] If the insulation resistance sensor 40 detects that the resistance value in the manifold 31 is less than the preset resistance value, and the pressure sensor 23 detects that the pressure value in the liquid inlet pipe 22 is less than the preset pressure value, it indicates that there is leakage in the manifold 31, and the leakage is leakage of coolant. At this time, the battery management system 50 controls the liquid inlet pipe 22 to be cut off through the first control valve 24, preventing the coolant from continuing to enter the liquid cooling plate 21 through the liquid inlet pipe 22, causing the leakage in the battery pack to continue to increase, thereby avoiding a short circuit.

[0061] In this way, the battery management system 50 in the battery pack of the present application determines whether there is leakage through the detection result of the insulation resistance sensor 40, and when there is leakage, it uses the detection result of the pressure sensor 23 to determine whether the leakage is leakage of coolant. Only when it is determined that the leakage in the collecting tank 31 is leakage of coolant, the battery management system 50 controls the liquid inlet pipe 22 to be cut off through the first control valve 24, thereby avoiding blindly closing the liquid inlet pipe 22 and stopping cooling the battery module 10, improving the cooling effect, and reducing the risk of thermal runaway of the battery module 10.

[0062] It should be noted that the material of the liquid collecting member 30 can be a low-density closed-cell foam material, which has the characteristics of non-absorbent, light weight and low thermal conductivity, and can play a certain role in heat insulation on the surface of the liquid cooling plate 21. In a low-temperature environment, the liquid collecting member 30 can play a heat-insulating function on the liquid cooling plate 21 and reduce the heat loss of the liquid cooling plate 21; in a high-temperature environment, the liquid collecting member 30 can reduce the risk of condensation on the surface of the liquid cooling plate 21.

[0063] Specifically in the embodiment, the box body 81 has an opening 810, and the battery pack further includes a cover plate 82 covering the opening 810 of the box body 81, so that the battery module 10, the liquid cooling assembly, the liquid collecting member 30, the insulation resistance sensor 40, and the battery management system 50 are encapsulated in the box body 81 by the cover plate 82. Further, the battery pack further includes a sealing ring 83 disposed between the box body 81 and the cover plate 82, and the sealing ring 83 is used to seal the gap between the box body 81 and the cover plate 82 to ensure that the sealing performance of the battery pack meets the requirements.

[0064] Specifically in the embodiment, the liquid cooling assembly further includes a second control valve 26, which is installed on the liquid outlet pipe 25 and is used to control the conduction or cutoff of the liquid outlet pipe 25. The second control valve 26 is electrically connected to the battery management system 50 through a wiring harness, so that when the insulation resistance sensor 40 detects that the resistance value in the manifold 31 is less than the preset resistance value, and the pressure sensor 23 detects that the pressure value in the inlet pipe 22 is less than the preset pressure value, the battery management system 50 controls the inlet pipe 22 to be cut off through the first control valve 24, and the battery management system 50 also controls the outlet pipe 25 to be cut off through the second control valve 26, on the one hand, to prevent the coolant from entering the liquid cooling plate 21 through the inlet pipe 22, which causes the leakage in the manifold 31 to continue to increase; on the other hand, to prevent the coolant from being sucked back into the liquid cooling plate 21 through the outlet pipe 25, which causes the leakage in the manifold 31 to continue to increase.

[0065] In an embodiment of the present application, the battery pack further includes a first drain valve 70, a first liquid level sensor 60, a second drain valve 71, and a second liquid level sensor 61, all of which are electrically connected to the battery management system 50 through a wiring harness. The two ends of the liquid collecting member 30 in the preset direction X are respectively a first end a1 and a second end a2. The first drain valve 70 is connected to a portion of the collecting tank 31 located at the first end a1, and the second drain valve 71 is connected to a portion of the collecting tank 31 located at the second end a2. The first liquid level sensor 60 is installed in the collecting tank 31 and is located at the first end a1 of the liquid collecting member 30. The second liquid level sensor 61 is installed in the collecting tank 31 and is located at the second end a2 of the liquid collecting member 30.

[0066] The battery management system 50 is used to control the opening or closing of the first drain valve 70 according to the detection result of the first liquid level sensor 60. The battery management system 50 is also used to control the opening or closing of the second drain valve 71 according to the detection result of the second liquid level sensor 61. When the first drain valve 70 is opened, the leaked liquid in the manifold 31 can be discharged to the outside of the battery pack box 81, and when the first drain valve 70 is closed, the leaked liquid in the manifold 31 is stopped from being discharged. Similarly, when the second drain valve 71 is opened, the leaked liquid in the manifold 31 can be discharged to the outside of the battery pack box 81, and when the second drain valve 71 is closed, the leaked liquid in the manifold 31 is stopped from being discharged.

[0067] It should be noted that when the battery pack is used on a vehicle, the first end a1 of the liquid collecting member 30 is close to the front end of the vehicle, and the second end a2 of the liquid collecting member 30 is close to the rear end of the vehicle (or the second end a2 of the liquid collecting member 30 is close to the front end of the vehicle, and the first end a1 of the liquid collecting member 30 is close to the rear end of the vehicle). If the vehicle leaks when going uphill, downhill, accelerating, decelerating or braking, the liquid level at the first end a1 in the collecting tank 31 is different from the liquid level at the second end a2. If the first drain valve 70 and the second drain valve 71 are opened blindly to drain the liquid, it may not achieve the effect of rapid drainage, but instead cause the liquid to accumulate in the box, increasing the safety risk, and even increase the risk of foreign matter entering the box 81 of the battery pack.

[0068] Thus, in actual use, the first drain valve 70 and the second drain valve 71 are in a normally closed state, and the first liquid level sensor 60 and the second liquid level sensor 61 monitor the liquid level at their respective locations in real time. If the liquid level detected by the first liquid level sensor 60 is greater than or equal to the first preset liquid level, and the liquid level detected by the second liquid level sensor 61 is less than the first preset liquid level, it indicates that the liquid level at the first end a1 in the manifold 31 has reached or exceeded the first preset liquid level, and the battery management system 50 controls the first drain valve 70 to open, so that the first drain valve 70 removes the leaked liquid in the manifold 31 from the first end a1. During the process of the first drain valve 70 draining liquid, if the liquid level detected by the second liquid level sensor 61 is greater than or equal to the second preset liquid level (the second preset liquid level is less than the first preset liquid level), the battery management system 50 controls the second drain valve 71 to open, so that the second drain valve 71 performs auxiliary draining at the second end a2. During the process in which the first drain valve 70 is draining and the second drain valve 71 is assisting in draining, if the liquid level height detected by the second drain valve 71 is lower than the second preset liquid level height, the battery management system 50 controls the second drain valve 71 to be cut off and stop draining; if the liquid level height detected by the first drain valve 70 is lower than the second preset liquid level height, the battery management system 50 controls the first drain valve 70 to be cut off and stop draining.

[0069] If the liquid level detected by the second liquid level sensor 61 is greater than or equal to the first preset liquid level, and the liquid level detected by the first liquid level sensor 60 is less than the first preset liquid level, it indicates that the liquid level at the second end a2 in the manifold 31 reaches or exceeds the first preset liquid level, and the battery management system 50 controls the second drain valve 71 to open, so that the second drain valve 71 removes the leaked liquid in the manifold 31 at the second end a2. During the process of the second drain valve 71 draining liquid, if the liquid level detected by the first liquid level sensor 60 is greater than or equal to the second preset liquid level (the second preset liquid level is less than the first preset liquid level), the battery management system 50 controls the first drain valve 70 to open, so that the first drain valve 70 performs auxiliary draining at the first end a1. During the process in which the second drain valve 71 is draining and the first drain valve 70 is assisting in draining, if the liquid level detected by the first drain valve 70 is lower than the second preset liquid level, the battery management system 50 controls the first drain valve 70 to be cut off and stop draining; if the liquid level detected by the second drain valve 71 is lower than the second preset liquid level, the battery management system 50 controls the second drain valve 71 to be cut off and stop draining.

[0070] If the liquid level detected by the first liquid level sensor 60 is greater than or equal to the first preset liquid level, and the liquid level detected by the second liquid level sensor 61 is also greater than or equal to the first preset liquid level, it indicates that the liquid level at the first end a1 and the second end a2 in the manifold 31 is greater than or equal to the first preset liquid level, and the battery management system 50 controls the first drain valve 70 and the second drain valve 71 to open, so that the first drain valve 70 drains the leaked liquid in the manifold 31 at the first end a1, and the second drain valve 71 drains the leaked liquid in the manifold 31 at the second end a2. During the process of draining liquid by the first drain valve 70 and the second drain valve 71, if the liquid level detected by the first liquid level sensor 60 is less than the second preset liquid level, the battery management system 50 controls the first drain valve 70 to be closed and the draining is stopped; if the liquid level detected by the second liquid level sensor 61 is less than the second preset liquid level, the battery management system 50 controls the second drain valve 71 to be closed and the draining is stopped. By setting the second preset liquid level height, the drain valve can be closed as early as possible to reduce the risk of foreign matter entering the box body 81 of the battery pack.

[0071] Specifically in the embodiment, the battery pack further includes an electrical connector 12 and a relay 14. The electrical connector 12 is electrically connected to the battery module 10 through the relay 14, so that the electrical energy of the battery module 10 can be output to the outside (i.e., discharge) through the electrical connector 12 or the external electrical energy can be input to the battery module 10 through the electrical connector 12 (i.e., charging). The relay 14 is electrically connected to the battery management system 50, and the battery management system 50 is used to control the relay 14 to be closed or opened according to the detection results of the first liquid level sensor 60 and the second liquid level sensor 61.

[0072] In this way, during actual use, the relay 14 is in a closed state, and the first liquid level sensor 60 and the second liquid level sensor 61 monitor the liquid level height at their respective locations in real time. If the liquid level height detected by the first liquid level sensor 60 and / or the second liquid level sensor 61 is greater than or equal to the first preset liquid level height, the battery management system 50 controls the relay 14 to disconnect, thereby cutting off the electrical connection between the battery module 10 and the outside, and stopping power supply to the outside. If the liquid level heights detected by the first liquid level sensor 60 and the second liquid level sensor 61 are both less than the first preset liquid level height, the battery management system 50 controls the relay 14 to close, thereby restoring the electrical connection between the battery module 10 and the outside, and continuing to supply power to the outside.

[0073] In an embodiment of the present application, the surface of the liquid cooling plate 21 on one side facing the battery module 10 has a cooling area and a peripheral area arranged around the cooling area. The cooling area is provided with a cooling channel, and the peripheral area may not be provided with a cold zone channel. The battery module 10 is arranged in the cooling area of ​​the liquid cooling plate 21, and the liquid collecting part 30 is arranged in the peripheral area of ​​the liquid cooling plate 21 to concentrate the cold and ensure the overall cooling effect. The collecting groove 31 is opened on the side of the liquid collecting part 30 away from the liquid cooling plate 21. In this way, the coolant leaked from the liquid cooling plate 21 is collected in the collecting groove 31. When the liquid level height in the collecting groove 31 is greater than or equal to the first preset liquid level height, the battery module 10 or other conductive components are at a greater risk of contacting the leaked liquid. At this time, the leaked liquid in the collecting groove 31 needs to be discharged to the outside of the battery pack box 81.

[0074] Furthermore, the liquid collecting member 30 also has a first drainage slope 32 located outside the collecting groove 31, and the first drainage slope 32 is arranged around the collecting groove 31. The height of the inner side of the first drainage slope 32 relative to the liquid cooling plate 21 is the first inner height, and the height of the outer side of the first drainage slope 32 relative to the liquid cooling plate 21 is the first outer height. The first outer height is greater than the first inner height, so that the first drainage slope 32 is a slope with a high outer side and a low inner side, ensuring that the leaked liquid can flow along the first drainage slope 32 into the collecting groove 31. The liquid collecting member 30 is arranged in the box body 81 and connected to the side wall of the box body 81, so as to facilitate the condensation on the side wall of the box body 81 to be guided from the first drainage slope 32 to the collecting groove 31, thereby improving the timeliness and accuracy of liquid detection.

[0075] Furthermore, the liquid collecting part 30 also has a second drainage slope 33 located between the collecting trough 31 and the battery module 10. The second drainage slope 33 is arranged around the battery module 10. The height of the inner side of the second drainage slope 33 (the side close to the battery module 10) relative to the liquid cooling plate 21 is the second inner height, and the height of the outer side of the second drainage slope 33 relative to the liquid cooling plate 21 is the second outer height. The second inner height is greater than the second outer height, so that the second drainage slope 33 is a slope with a high inner side and a low outer side, ensuring that the leaked liquid can flow along the second drainage slope 33 into the collecting trough 31. By relatively arranging the first drainage slope 32 and the second drainage slope 33, it is convenient to concentrate the leaked liquid and / or condensation into the collecting trough 31, which is convenient for detecting the liquid level height, improving the timeliness of detection, and ensuring overall safety.

[0076] Specifically in the embodiment, the liquid collecting member 30 also has a first drainage groove 34 and a first avoidance hole 36. The first drainage groove 34 is opened on the second drainage slope 33 and is connected to the collecting groove 31. The first avoidance hole 36 is located in the first drainage groove 34, and passes through the first drainage groove 34 to the side of the liquid collecting member 30 facing the liquid cooling plate 21. One end of the liquid inlet pipe 22 passes through the first avoidance hole 36 and is connected to the liquid inlet 211 of the liquid cooling plate 21. In this way, since there is a greater risk of leakage at the connection between the liquid inlet pipe 22 and the liquid inlet 211 of the liquid cooling plate 21, the first avoidance hole 36 and the first drainage groove 34 are provided, so that when leakage occurs at the connection between the liquid inlet pipe 22 and the liquid inlet 211 of the liquid cooling plate 21, the leakage can be quickly collected in the collecting groove 31.

[0077] Furthermore, the insulation resistance sensor 40 is disposed in the first drainage groove 34, so that the insulation resistance sensor 40 can detect the leakage more quickly, which is conducive to improving the timeliness and accuracy of the leakage detection. Specifically, a first installation groove 38 is provided in the first drainage groove 34, and the insulation resistance sensor 40 is installed in the first installation groove 38.

[0078] Specifically in the embodiment, the liquid collecting part 30 also has a second drainage groove 35 and a second avoidance hole 37. The second drainage groove 35 is opened on the second drainage slope 33 and is connected to the collecting groove 31. The second avoidance hole 37 is located in the second drainage groove 35, and is penetrated from the second drainage groove 35 to the side of the liquid collecting part 30 facing the liquid cooling plate 21. One end of the liquid outlet pipe 25 passes through the second avoidance hole 37 and is connected to the liquid outlet 213 of the liquid cooling plate 21. In this way, since there is a greater risk of leakage at the connection between the liquid outlet pipe 25 and the liquid outlet 213 of the liquid cooling plate 21, the second avoidance hole 37 and the second drainage groove 35 are provided, so that when leakage occurs at the connection between the liquid outlet pipe 25 and the liquid outlet 213 of the liquid cooling plate 21, the leakage can be quickly collected in the collecting groove 31.

[0079] Furthermore, the insulation resistance sensor 40 is disposed in the second drainage groove 35, so that the insulation resistance sensor 40 can detect the leakage more quickly, which is conducive to improving the timeliness and accuracy of the detection of the leakage phenomenon. Specifically, a first installation groove 38 is provided in the second drainage groove 35, and the insulation resistance sensor 40 is installed in the first installation groove 38 to accommodate the insulation resistance sensor 40, which can not only play a limiting role, but also isolate the insulation resistance sensor 40 and the liquid cooling plate 21.

[0080] It should be noted that in addition to setting the insulation resistance sensor 40 in the first drainage groove 34 and the second drainage groove 35, one or more first installation grooves 38 can also be opened at other positions of the collecting groove 31, and each first installation groove 38 is provided with an insulation resistance sensor 40. Each insulation resistance sensor 40 is used to monitor the resistance of each position of the collecting groove 31 in real time, which is beneficial to improve the accuracy and timeliness of leakage detection.

[0081] Specifically in the embodiment, a second mounting groove 39 and a third mounting groove 391 are further provided in the manifold 31, the second mounting groove 39 is located at the first end a1 of the liquid collecting member 30, and the third mounting groove 391 is located at the second end a2 of the liquid collecting member 30. The first liquid level sensor 60 is installed in the second mounting groove 39, and the second liquid level sensor 61 is installed in the third mounting groove 391. It can not only play a limiting role, but also isolate the liquid level sensor and the liquid cooling plate 21.

[0082] Optionally, the number of the second installation slots 39 may be two or more, and a first liquid level sensor 60 is installed in each second installation slot 39. The number of the third installation slots 391 may be two or more, and a second liquid level sensor 61 is installed in each third installation slot 391. Figure 4In the illustrated embodiment, the number of the second mounting grooves 39 is two, and the two second mounting grooves 39 are respectively located at the two ends of one side of the liquid collecting member 30 in the preset direction X. The number of the third mounting grooves 391 is also two, and the two third mounting grooves 391 are respectively located at the two ends of the other side of the liquid collecting member 30 in the preset direction X. That is, the two first liquid level sensors 60 are arranged at the two ends of one side of the preset direction X, that is, at the two ends of the side where the first end (a1) is set. The two second liquid level sensors 61 are arranged at the two ends of the other side of the preset direction X, that is, at the two ends of the side where the second end (a2) is set. The first liquid level sensors 60 and the second liquid level sensors 61 are arranged opposite to each other along the preset direction X, and liquid level sensors are arranged at four positions of the liquid collecting member 60, thereby expanding the detection range and improving the detection accuracy. That is, the collecting trough 31 is arranged around the liquid collecting part 30 and is closed and connected. A plurality of liquid level sensors are respectively arranged at the four corners of the collecting trough 31. No matter how the liquid collecting part 60 is tilted and turned, it can ensure that the liquid can flow along the collecting trough 31 to different corner positions, so as to be detected by the liquid level sensor at the corner position, thereby avoiding missed detection and improving overall safety. It is particularly suitable for driving, such as uphill, downhill, acceleration, deceleration or turning, and can accurately detect the liquid for precise discharge. It can be understood that the first discharge valve (70) is arranged at the first end (a1), and when the liquid flows to the first end (a1), precise discharge is achieved by controlling the first discharge valve (70); the second discharge valve (71) is arranged at the second end (a2), and when the liquid flows to the second section (a2), precise discharge is achieved by controlling the second discharge valve (71). In order to improve the accuracy, drain valves can be set at the four corners of the manifold 31. When the liquid level sensor 60 at any corner is detected to be abnormal, the drain valve corresponding to the corner can be controlled to drain the liquid, and the drain valves at other corners can be controlled to close, thereby ensuring the accuracy of liquid discharge. The first drain valve 70 and the second drain valve 71 are set at the first end and the second end, and the inertia of the liquid during driving can be used to improve the drainage efficiency and speed up the liquid discharge.

[0083] In an optional embodiment, a first drain valve 70 and a second drain valve 71 are respectively arranged at the first end a1 and the second end a2 of the manifold 31. A first drain valve 70 and a second drain valve 71 can be respectively arranged at any position of the side where the first end a1 is located and the side where the second end a2 is located, so as to ensure that when the liquid flows to any corner of the manifold 31, the liquid can still be accurately drained, and the number of drain valves can be reduced, so as to save costs, simplify the overall structure, and control strategy. When any first liquid level sensor 60 located at the first end a1 detects that the liquid level reaches the first preset height, the first drain valve 70 can be controlled to open for draining, even if the liquid level detected by the first liquid level sensor 60 close to the first drain valve 70 does not reach the first preset height, there is more liquid at the other corner of the first end a1 at this time, and the liquid can also be drained through the first drain valve 70. Optionally, when any liquid level sensor far away from the drain valve detects that the liquid level reaches the first preset height, the drain valve closest to it can be controlled to open for draining to improve the draining efficiency.

[0084] In another optional embodiment, reference Figure 3 As shown, a first drain valve 70 and a second drain valve 71 are arranged at the first end a1 and the second end a2 of the manifold 31, and are arranged at the diagonal position of the liquid collecting member 30, and the liquid level sensors are arranged at the four corner positions of the liquid collecting member 30. The drain valves and the liquid level sensors located at the same corner position are relatively close to each other for rapid drainage. At the same time, such a design can shorten the drainage path and avoid the situation where the liquid accumulates at the corner position most of the time when the drain valve is arranged at the central position of the side. Regardless of any corner position, the accumulated liquid needs to flow from the corner position. The drainage path is extended to the center, and when it is set at a diagonal position, even if the liquid level sensor at the corner far away from the drain valve detects that the liquid level height is higher than the first preset height, the drain valve closest to it can be controlled to open, thereby realizing accurate and rapid drainage. In order to speed up the drainage rate, the first drain valve 70 and the second drain valve 71 can be controlled to open at the same time, that is, when the liquid level sensor at the corner where the drain valve is not set detects that the liquid level height is greater than the first preset height, the first drain valve 70 and the second drain valve 71 are opened at the same time, thereby facilitating drainage.

[0085] Based on the above battery pack, this application also provides a leakage protection method. Figure 5 and Figure 6 As shown, in the first embodiment of the present application, the liquid leakage protection method includes the following steps:

[0086] S10, each insulation resistance sensor 40 monitors the resistance at its respective location in real time, the pressure sensor 23 monitors the pressure in the liquid inlet pipe 22 in real time, and each first liquid level sensor 60 and each second liquid level sensor 61 monitors the liquid level at its respective location in real time;

[0087] S20. If the resistance value detected by any insulation resistance sensor 40 is less than the preset resistance value, and the pressure detected by the pressure sensor 23 is less than the preset pressure, the battery management system 50 controls the liquid inlet pipe 22 to be cut off through the first control valve 24, and the battery management system 50 also controls the liquid outlet pipe 25 to be cut off through the second control valve 26, thereby preventing the coolant from continuing to enter the liquid cooling plate 21 and avoiding a continuous increase in the amount of leakage.

[0088] In this way, only when the resistance value detected by any insulation resistance sensor 40 is less than the preset resistance value, and the pressure detected by the pressure sensor 23 is less than the preset pressure, can it be determined that there is leakage in the collecting tank 31, and the leakage is the leakage of the coolant, so that the first control valve 24 and the second control valve 26 are respectively used to control the liquid inlet pipe 22 and the liquid outlet pipe 25 to be cut off to prevent more coolant from entering the liquid cooling plate 21 and causing the leakage to continue to increase. Compared with the prior art, the present application avoids blindly cutting off the circulation flow path of the coolant, which greatly reduces the heat dissipation capacity of the battery module 10, ensures the cooling effect of the battery module 10, and thus reduces the risk of thermal runaway of the battery module 10.

[0089] It should be noted that if the insulation resistance sensor 40 detects a resistance value less than a preset resistance value, and the pressure detected by the pressure sensor 23 is greater than or equal to a preset pressure, it indicates that the leaked liquid in the manifold 31 is not leaked coolant, that is, the coolant is not leaking. At this time, the battery management system 50 transmits information to the vehicle, so that the vehicle takes measures such as limiting the output power to achieve a speed reduction and / or alerting the driver to pull over.

[0090] Specifically in the embodiment, after step S20, step S30 is also included:

[0091] If the liquid level detected by at least one of the first liquid level sensors 60 and the second liquid level sensors 61 is greater than the first preset liquid level, the battery management system 50 controls the relay 14 to disconnect, thereby cutting off the electrical connection between the battery module 10 and the outside to avoid a short circuit accident due to excessive liquid level. It should be noted that when the liquid level in the collecting tank 31 reaches the first preset liquid level, the electrical components in the box 81 of the battery pack are at risk of short circuiting due to contact with the leaking liquid, so it is necessary to immediately cut off the conductive circuit (i.e., control the relay 14 to disconnect).

[0092] Furthermore, step S30 further includes step S40:

[0093] The battery management system 50 controls the first drain valve 70 and / or the second drain valve 71 to open, so that the leaked liquid in the collecting tank 31 is discharged to the outside of the battery pack box 81 by using the first drain valve 70 and / or the second drain valve 71 to prevent the liquid level of the leaked liquid from continuing to increase.

[0094] Furthermore, after step S40, step S50 is also included:

[0095] If the liquid level heights detected by each of the first liquid level sensors 60 and each of the second liquid level sensors 61 are all less than the first preset liquid level height, the battery management system 50 controls the relay 14 to close. It should be noted that when the liquid level height of the leaked liquid in the manifold 31 is less than the first preset height, the risk of short circuit caused by contact between the electrical components in the battery pack and the leaked liquid is eliminated, and at this time the conductive circuit can be turned on (i.e., the relay 14 is controlled to close), thereby restoring the power of the entire vehicle.

[0096] Furthermore, after step S50, step S60 is also included:

[0097] If the liquid level height detected by each first liquid level sensor 60 is less than the second preset liquid level height, the battery management system 50 controls the first drain valve 70 to be closed, so that the first drain valve 70 located at the first end a1 stops draining liquid, thereby preventing the liquid outside the battery pack from entering the battery pack box 81 through the first drain valve 70 when the vehicle is wading, and also preventing the risk of foreign matter entering the battery pack box 81;

[0098] If the liquid level heights detected by the second liquid level sensors 61 are all lower than the second preset liquid level height, the battery management system 50 controls the second drain valve 71 to be cut off, so that the second drain valve 71 located at the second end a2 stops draining liquid, thereby preventing the liquid outside the battery pack from entering the battery pack box 81 through the second drain valve 71 when the vehicle is wading, and also preventing the risk of foreign matter entering the battery pack box 81.

[0099] It should be noted that when the liquid level height of the leakage in the collecting tank 31 is lower than the second preset liquid level height, the risk of short circuit caused by contact between the electrical components in the battery pack box 81 and the leakage is eliminated. At this time, due to the low liquid level height of the leakage in the collecting tank 31, the first drain valve 70 and the second drain valve 71 may not be able to continue draining. Therefore, it is necessary to control the first drain valve 70 and the second drain valve 71 to be cut off in time, which can further prevent foreign matter from entering the box 81.

[0100] See also Figure 7 and Fig. 9 As shown, in the second embodiment of the present application, the second embodiment is similar to the first embodiment, and the differences between the second embodiment and the first embodiment are described below:

[0101] After step S30, the method further includes step S40:

[0102] If the liquid level detected by at least one first liquid level sensor 60 is greater than or equal to the first preset liquid level, and the liquid level detected by each second liquid level sensor 61 is less than the first preset liquid level, the battery management system 50 controls the first drain valve 70 to open, so that the first drain valve 70 at the first end a1 discharges the leaked liquid in the manifold 31 to the outside of the battery pack box 81. It should be noted that at this time, due to factors such as the vehicle going up and downhill or accelerating and decelerating, the liquid level at the first end a1 in the manifold 31 is higher, and the liquid level at the second end a2 is lower, so only the first drain valve 70 at the first end a1 is opened for draining, which is conducive to achieving accurate drainage and avoiding the entry of foreign matter caused by opening another exhaust valve, thereby reducing risks.

[0103] Furthermore, after step S40, step S50 is also included:

[0104] If the liquid level detected by at least one second liquid level sensor 61 is greater than or equal to the second preset liquid level, the battery management system 50 controls the second drain valve 71 to open (at this time the first drain valve 70 and the second drain valve 71 drain liquid at the same time), thereby utilizing the second drain valve 71 to assist in draining liquid and increase the drain efficiency.

[0105] Furthermore, after step S50, step S60 is also included:

[0106] If the liquid level heights detected by each of the first liquid level sensors 60 and each of the second liquid level sensors 61 are all less than the first preset liquid level height, it indicates that the risk of short circuit caused by contact between the electrical components in the battery pack box 81 and the leaking liquid has been eliminated. At this time, the battery management system 50 controls the relay 14 to close, so that the conductive circuit is turned on and the vehicle recovers power.

[0107] If the liquid level detected by each first liquid level sensor 60 is lower than the second preset liquid level, it indicates that the liquid level of the leaked liquid in the manifold 31 at the first end a1 is relatively low, causing the first drain valve 70 to be unable to drain liquid any more. At this time, the battery management system 50 controls the first drain valve 70 to be closed.

[0108] If the liquid level heights detected by each second liquid level sensor 61 are lower than the second preset liquid level height, it indicates that the liquid level height of the leaked liquid in the collecting tank 31 at the second end a2 is relatively low, causing the second drain valve 71 to be unable to drain liquid any further. At this time, the battery management system 50 controls the second drain valve 71 to be cut off.

[0109] See also Figure 8 and Fig. 9 As shown, in the third embodiment of the present application, the third embodiment is similar to the second embodiment, and the differences between the third embodiment and the second embodiment are described below:

[0110] After step S30, the method further includes step S40:

[0111] If the liquid level detected by the first liquid level sensor 60 is less than the first preset liquid level, and the liquid level detected by the second liquid level sensor 61 is greater than or equal to the first preset liquid level, the battery management system 50 controls the second drain valve 71 to open, so that the second drain valve 71 at the second end a2 discharges the leaked liquid in the manifold 31 to the outside of the battery pack. It should be noted that at this time, due to factors such as the vehicle going up and downhill or accelerating and decelerating, the liquid level at the second end a2 in the manifold 31 is higher, and the liquid level at the first end a1 is lower, so only the second drain valve 71 at the second end a2 is opened for draining, which is conducive to achieving accurate drainage.

[0112] After step S40, the method further includes step S50:

[0113] If the liquid level height detected by at least one first liquid level sensor 60 is greater than or equal to the second preset liquid level height, the battery management system 50 controls the first drain valve 70 to open, thereby utilizing the first drain valve 70 to assist in draining liquid (at this time, the first drain valve 70 and the second drain valve 71 drain liquid at the same time), thereby increasing the drainage efficiency.

[0114] After step S50, the method further includes step S60:

[0115] If the liquid level heights detected by each of the first liquid level sensors 60 and each of the second liquid level sensors 61 are all less than the first preset liquid level height, it indicates that the risk of short circuit caused by contact between the electrical components in the battery pack and the leaking liquid has been eliminated. At this time, the battery management system 50 controls the relay 14 to close, so that the conductive circuit is turned on and continues to provide power for the vehicle.

[0116] If the liquid level detected by each first liquid level sensor 60 is lower than the second preset liquid level, it indicates that the liquid level of the leakage in the manifold 31 at the first end a1 is relatively low, causing the first drain valve 70 to be unable to drain any more liquid. At this time, the battery management system 50 controls the first drain valve 70 to be closed.

[0117] If the liquid level detected by each second liquid level sensor 61 is lower than the second preset liquid level, it indicates that the liquid level at the second end a2 of the leakage in the collecting tank 31 is relatively low, causing the second drain valve 71 to be unable to drain any more liquid. At this time, the battery management system 50 controls the second drain valve 71 to be cut off.

[0118] See also Fig.10 As shown, in the fourth embodiment of the present application, the fourth embodiment is similar to the third embodiment, and the differences between the fourth embodiment and the third embodiment are described below:

[0119] After step S30, the method further includes step S40:

[0120] If the liquid level detected by at least one first liquid level sensor 60 is greater than or equal to the first preset liquid level, and the liquid level detected by at least one second liquid level sensor 61 is also greater than or equal to the first preset liquid level, the battery management system 50 controls the first drain valve 70 and the second drain valve 71 to open, so that the first drain valve 70 located at the first end a1 and the second drain valve 71 located at the second end a2 simultaneously discharge the leaked liquid in the collecting tank 31 to the outside of the battery pack.

[0121] After step S40, the method further includes step S50:

[0122] If the liquid level heights detected by each of the first liquid level sensors 60 and each of the second liquid level sensors 61 are all less than the first preset liquid level height, it indicates that the risk of short circuit caused by contact between the electrical components in the battery pack and the leaking liquid has been eliminated. At this time, the battery management system 50 controls the relay 14 to close, so that the conductive circuit is turned on and continues to provide power for the vehicle.

[0123] If the liquid level detected by each first liquid level sensor 60 is lower than the second preset liquid level, it indicates that the liquid level of the leakage in the manifold 31 at the first end a1 is relatively low, causing the first drain valve 70 to be unable to drain any more liquid. At this time, the battery management system 50 controls the first drain valve 70 to be closed.

[0124] If the liquid level heights detected by each second liquid level sensor 61 are all lower than the second preset liquid level height, it indicates that the liquid level height of the leakage in the collecting tank 31 at the second end a2 is relatively low, causing the second drain valve 71 to be unable to continue draining liquid. At this time, the battery management system 50 controls the second drain valve 71 to be cut off.

[0125] Through the present application, in the leakage detection and processing method, it is possible to directly detect whether the liquid cooling plate 21 is leaking, thereby improving the accuracy of leakage detection, avoiding the mistaken detection of leakage of the liquid cooling plate 21 and causing the liquid cooling plate 21 to be mistakenly closed, thereby affecting the cooling effect. At the same time, accurate processing can be performed according to the leakage situation, while ensuring the drainage efficiency, thereby improving the overall work efficiency and safety. The leakage situation under different working conditions can be detected and then the corresponding drainage processing can be performed. During drainage, the drainage efficiency can be improved so that the leakage can be discharged as soon as possible. At the same time, the situation where the leakage accumulates and cannot be discharged can be avoided. In addition, the drainage can be closed in time according to the detection situation, thereby improving the overall safety and practicality.

[0126] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0127] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A battery pack, characterized in that: include: Battery module (10); A liquid cooling component, comprising a liquid cooling plate (21), a liquid inlet pipe (22), a pressure sensor (23) and a first control valve (24); the battery module (10) is arranged on the liquid cooling plate (21), the liquid inlet pipe (22) is connected to the liquid inlet (211) of the liquid cooling plate (21), the pressure sensor (23) and the first control valve (24) are both installed on the liquid inlet pipe (22), the pressure sensor (23) is used to detect the pressure in the liquid inlet pipe (22), and the first control valve (24) is used to control the liquid inlet pipe (22) to be turned on or off; A liquid collecting member (30) having a collecting groove (31) arranged around the peripheral edge of the liquid cooling plate (21), wherein the collecting groove (31) is used to collect leaked liquid; An insulation resistance sensor (40) is arranged in the current collecting tank (31) and is used to detect the resistance at the location; A battery management system (50) is electrically connected to the pressure sensor (23), the first control valve (24) and the insulation resistance sensor (40); the battery management system (50) is used to control the liquid inlet pipe (22) to be cut off through the first control valve (24) according to the detection results of the insulation resistance sensor (40) and the pressure sensor (23).

2. The battery pack according to claim 1, characterized in that: The liquid cooling plate (21) has a cooling area and a peripheral area arranged around the cooling area on a side surface facing the battery module (10); the battery module (10) is arranged in the cooling area, the liquid collecting member (30) is arranged in the peripheral area, and the collecting groove (31) is opened on a side of the liquid collecting member (30) facing away from the liquid cooling plate (21).

3. The battery pack according to claim 2, characterized in that: The liquid collecting member (30) further comprises a first drainage slope (32) located outside the collecting groove (31), the first drainage slope (32) being arranged around the collecting groove (31), the inner side of the first drainage slope (32) having a height relative to the liquid cooling plate (21) being a first inner side height, the outer side of the first drainage slope (32) having a height relative to the liquid cooling plate (21) being a first outer side height, and the first outer side height being greater than the first inner side height; The liquid collecting member (30) further comprises a second drainage slope (33) located between the collecting groove (31) and the battery module (10); the second drainage slope (33) is arranged around the battery module (10); the inner side of the second drainage slope (33) has a second inner side height relative to the liquid cooling plate (21); the outer side of the second drainage slope (33) has a second outer side height relative to the liquid cooling plate (21); and the second inner side height is greater than the second outer side height.

4. The battery pack according to claim 3, characterized in that: The liquid collecting member (30) further comprises a first drainage groove (34) and a first avoidance hole (36); the first drainage groove (34) is provided on the second drainage inclined surface (33) and is communicated with the collecting groove (31); the first avoidance hole (36) is located in the first drainage groove (34) and penetrates from the first drainage groove (34) to a side of the liquid collecting member (30) facing the liquid cooling plate (21); One end of the liquid inlet pipe (22) passes through the first avoidance hole (36) and is connected to the liquid inlet (211) of the liquid cooling plate (21), and the insulation resistance sensor (40) is arranged in the first drainage groove (34).

5. The battery pack according to any one of claims 1 to 4, characterized in that: The battery pack further comprises a first drain valve (70), a first liquid level sensor (60), a second drain valve (71) and a second liquid level sensor (61), all of which are electrically connected to the battery management system (50); The two ends of the liquid collecting member (30) in a preset direction (X) are respectively a first end (a1) and a second end (a2); the first liquid discharge valve (70) is in communication with a portion of the collecting tank (31) located at the first end (a1); the second liquid discharge valve (71) is in communication with a portion of the collecting tank (31) located at the second end (a2); the first liquid level sensor (60) is installed in the collecting tank (31) and is located at the first end (a1); the second liquid level sensor (61) is installed in the collecting tank (31) and is located at the second end (a2); The battery management system (50) is used to control the first drain valve (70) to be opened or closed according to the detection result of the first liquid level sensor (60), and is also used to control the second drain valve (71) to be opened or closed according to the detection result of the second liquid level sensor (61).

6. A leakage protection method for a battery pack according to any one of claims 1 to 5, characterized in that: The following steps are involved: The insulation resistance sensor (40) monitors the resistance at the location in real time, and the pressure sensor (23) monitors the pressure in the liquid inlet pipe (22) in real time; If the resistance value detected by the insulation resistance sensor (40) is less than a preset resistance value, and the pressure detected by the pressure sensor (23) is less than a preset pressure, the battery management system (50) controls the liquid inlet pipe (22) to be cut off through the first control valve (24).

7. The liquid leakage protection method according to claim 6, characterized in that: The first liquid level sensor (60) and the second liquid level sensor (61) respectively monitor the liquid level heights at their respective locations in real time; After the step of the first control valve (24) controlling the liquid inlet pipe (22) to be cut off, the following step further comprises: If the liquid level height detected by at least one of the first liquid level sensor (60) and the second liquid level sensor (61) is greater than a first preset liquid level height, the battery management system (50) controls the relay (14) to disconnect.

8. The liquid leakage protection method according to claim 7, characterized in that: After the step of the battery management system (50) controlling the relay (14) to disconnect, the step further includes: The battery management system (50) controls the first drain valve (70) and / or the second drain valve (71) to open; If the liquid level heights detected by the first liquid level sensor (60) and the second liquid level sensor (61) are both lower than the first preset liquid level height, the battery management system (50) controls the relay (14) to close; If the liquid level detected by the first liquid level sensor (60) is less than a second preset liquid level, the battery management system (50) controls the first drain valve (70) to be closed; wherein the second preset liquid level is less than the first preset liquid level; If the liquid level detected by the second liquid level sensor (61) is less than the second preset liquid level, the battery management system (50) controls the second liquid drain valve (71) to be closed.

9. The liquid leakage protection method according to claim 7, characterized in that: After the step of the battery management system (50) controlling the relay (14) to disconnect, the method further includes: If the liquid level detected by the first liquid level sensor (60) is greater than or equal to a first preset liquid level, and the liquid level detected by the second liquid level sensor (61) is less than the first preset liquid level, the battery management system (50) controls the first drain valve (70) to open; If the liquid level detected by the second liquid level sensor (61) is greater than or equal to a second preset liquid level, the battery management system (50) controls the second drain valve (71) to open; wherein the second preset liquid level is less than the first preset liquid level; If the liquid level heights detected by the first liquid level sensor (60) and the second liquid level sensor (61) are both less than the first preset liquid level height, the battery management system (50) controls the relay (14) to close; If the liquid level detected by the first liquid level sensor (60) is less than the second preset liquid level, the battery management system (50) controls the first drain valve (70) to be closed; If the liquid level detected by the second liquid level sensor (61) is less than the second preset liquid level, the battery management system (50) controls the second liquid drain valve (71) to be closed.

10. The liquid leakage protection method according to claim 7, characterized in that: After the step of the battery management system (50) controlling the relay (14) to disconnect, the method further includes: If the liquid level detected by the second liquid level sensor (61) is greater than or equal to a first preset liquid level, and the liquid level detected by the first liquid level sensor (60) is less than the first preset liquid level, the battery management system (50) controls the second drain valve (71) to open; If the liquid level detected by the first liquid level sensor (60) is greater than or equal to a second preset liquid level, the battery management system (50) controls the first drain valve (70) to open; wherein the second preset liquid level is less than the first preset liquid level.

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