阅读说明：本技术 一种电池包冷却液自动排空装置及方法 (Automatic emptying device and method for battery pack cooling liquid ) 是由 焦少斌 徐封 于 2021-07-19 设计创作，主要内容包括：本发明提供了一种电池包冷却液自动排空装置及方法,包括：气源管道、第一支管、第二支管、第三支管、第四支管、旁路管道、上位机、与上位机通讯连接的水冷机和电池包；第一支管的一端与电池包的进液口连通,其另一端选择性与第二支管或气源管道连通；第二支路管道与水冷机的出液口连通；第三支管的一端与电池包的出液口连通,其另一端选择性与第四支管或旁路管道连通；第四支管与水冷机的回液口连通；旁路管道与水冷机的储液口连通。本发明可以实现冷却液的自动回收利用,整个排液过程无需手动操作,简化电池包冷却液排液操作。(The invention provides a device and a method for automatically emptying battery pack cooling liquid, which comprises the following steps: the system comprises an air source pipeline, a first branch pipe, a second branch pipe, a third branch pipe, a fourth branch pipe, a bypass pipeline, an upper computer, a water cooling machine and a battery pack, wherein the water cooling machine and the battery pack are in communication connection with the upper computer; one end of the first branch pipe is communicated with the liquid inlet of the battery pack, and the other end of the first branch pipe is selectively communicated with the second branch pipe or the gas source pipeline; the second branch pipeline is communicated with a liquid outlet of the water cooling machine; one end of the third branch pipe is communicated with a liquid outlet of the battery pack, and the other end of the third branch pipe is selectively communicated with the fourth branch pipe or the bypass pipeline; the fourth branch pipe is communicated with a liquid return port of the water cooler; the bypass pipeline is communicated with a liquid storage port of the water cooling machine. The battery pack cooling liquid draining device can realize automatic recycling of cooling liquid, does not need manual operation in the whole draining process, and simplifies the battery pack cooling liquid draining operation.)

1. An automatic emptying device of battery pack cooling liquid is characterized by comprising: the system comprises an air source pipeline, a first branch pipe, a second branch pipe, a third branch pipe, a fourth branch pipe, a bypass pipeline, an upper computer, a water cooling machine and a battery pack, wherein the water cooling machine and the battery pack are in communication connection with the upper computer; one end of the first branch pipe is communicated with the liquid inlet of the battery pack, and the other end of the first branch pipe is selectively communicated with the second branch pipe or the gas source pipeline; the second branch pipeline is communicated with a liquid outlet of the water cooling machine; one end of the third branch pipe is communicated with a liquid outlet of the battery pack, and the other end of the third branch pipe is selectively communicated with the fourth branch pipe or the bypass pipeline; the fourth branch pipe is communicated with a liquid return port of the water cooling machine; the bypass pipeline is communicated with a liquid storage port of the water cooling machine.

2. The automatic emptying device of battery pack coolant as claimed in claim 1, further comprising a first solenoid valve disposed at an end of the second branch pipe adjacent to the first branch pipe, and a second solenoid valve disposed at an end of the air supply pipe adjacent to the first branch pipe.

3. The automatic battery pack coolant evacuation device of claim 2, further comprising a third solenoid valve disposed at an end of the bypass line adjacent to the third branch line, and a fourth solenoid valve disposed at an end of the fourth branch line adjacent to the third branch line.

4. The automatic battery pack coolant evacuation device of claim 3, further comprising a pressure regulating valve disposed on the air supply line.

5. The automatic emptying device of battery pack coolant as claimed in claim 1, wherein the upper computer is connected with the water cooling machine and the battery pack through a CAN bus.

6. The automatic emptying device of battery pack coolant as claimed in claim 4, wherein the upper computer is connected with the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve and the pressure regulating valve through a CAN bus.

7. The automatic emptying method of the battery pack cooling liquid is characterized by being executed based on the automatic emptying device of the battery pack cooling liquid of claim 4, and specifically comprising the following steps:

the water cooling machine responds to a stop instruction sent by the upper computer and is switched to a stop state;

when the water cooling machine finishes the switching of the stop states, the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed, and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be opened, so that compressed air is introduced through the air source pipeline to enter a battery pack liquid discharging process;

when the time length of the battery pack liquid discharging process reaches a preset first time length threshold value, the upper computer controls the first battery valve and the fourth electromagnetic valve to be opened, controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be closed, and ends the battery pack liquid discharging process.

8. The method for automatically draining the cooling liquid of the pond package according to claim 7, wherein after the water cooling machine is switched to the stop state in response to a stop command sent by the upper computer, the method further comprises the following steps:

standing the water cooling machine, and monitoring the flow and the pressure of a liquid outlet of the water cooling machine;

judging whether the water-cooled machine meets any preset stop state switching condition; the stop state switching condition includes: the standing time of the water cooler reaches a preset second time threshold value, the flow of the liquid outlet of the water cooler is lower than a preset flow threshold value, the standing time of the water cooler reaches the preset second time threshold value, and the pressure of the liquid outlet of the water cooler is lower than a preset pressure threshold value;

if so, confirming that the water cooling machine completes the switching of the stop state;

if not, continuing to stand the water cooler.

9. The method for automatically emptying the cooling liquid in the tank pack according to claim 7, wherein the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be opened, and the method comprises the following steps:

the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed and controls the second electromagnetic valve and the third electromagnetic valve to be opened;

and when the standing time reaches a preset third time threshold, the upper computer controls the pressure regulating valve to be opened.

10. The method for automatically draining the cooling liquid in the tank pack according to claim 7, wherein the upper computer controls the first battery valve and the fourth electromagnetic valve to be opened and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be closed, and the method comprises the following steps:

the upper computer controls the pressure regulating valve to close;

and when the standing time reaches a preset fourth time threshold, the upper computer controls the second electromagnetic valve and the third electromagnetic valve to be closed and controls the first battery valve and the fourth electromagnetic valve to be opened.

Technical Field

The invention relates to the technical field of battery pack drainage of new energy automobiles, in particular to an automatic emptying device and method for battery pack cooling liquid.

Background

The power system of the new energy automobile adopts the battery for energy supply, the temperature requirement on the power battery pack is very strict in the battery energy supply process, and the working temperature of the power battery pack not only influences the performance of the battery pack, but also directly relates to the safety of the automobile. If the working temperature of the power battery pack exceeds a safety threshold, the battery pack is easy to cause a fire accident. In order to ensure that the working temperature of the battery pack of the new energy automobile is maintained in a safe range, the temperature control treatment needs to be carried out on the battery pack. At present, battery pack cooling liquid is mainly used as a heat dissipation medium for heat energy of the battery pack, and the temperature of the battery pack is controlled through a circulation process of the cooling liquid. However, the conventional battery pack requires frequent replacement of the coolant, and the battery pack coolant requires manual draining operation, which makes the draining operation complicated.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide an apparatus and a method for automatically draining coolant from a battery pack, which can automatically recycle the coolant and simplify the draining operation of the coolant from the battery pack.

In a first aspect, an embodiment of the present invention provides an automatic evacuation device for a battery pack coolant, including: the system comprises an air source pipeline, a first branch pipe, a second branch pipe, a third branch pipe, a fourth branch pipe, a bypass pipeline, an upper computer, a water cooling machine and a battery pack, wherein the water cooling machine and the battery pack are in communication connection with the upper computer; one end of the first branch pipe is communicated with the liquid inlet of the battery pack, and the other end of the first branch pipe is selectively communicated with the second branch pipe or the gas source pipeline; the second branch pipeline is communicated with a liquid outlet of the water cooling machine; one end of the third branch pipe is communicated with a liquid outlet of the battery pack, and the other end of the third branch pipe is selectively communicated with the fourth branch pipe or the bypass pipeline; the fourth branch pipe is communicated with a liquid return port of the water cooling machine; the bypass pipeline is communicated with a liquid storage port of the water cooling machine.

As an improvement of the above scheme, the automatic emptying device for battery pack coolant further comprises a first solenoid valve and a second solenoid valve, wherein the first solenoid valve is arranged at one end of the second branch pipe close to the first branch pipe, and the second solenoid valve is arranged at one end of the gas source pipeline close to the first branch pipe.

As an improvement of the above scheme, the automatic battery pack coolant evacuation device further includes a third solenoid valve and a fourth solenoid valve, the third solenoid valve is disposed at an end of the bypass pipe close to the third branch pipe, and the fourth solenoid valve is disposed at an end of the fourth branch pipe close to the third branch pipe.

As an improvement of the scheme, the automatic battery pack cooling liquid emptying device further comprises a pressure regulating valve, and the pressure regulating valve is arranged on the air source pipeline.

As an improvement of the scheme, the upper computer is connected with the water cooling machine and the battery pack through a CAN bus.

As an improvement of the scheme, the upper computer is connected with the first electromagnetic valve, the second electromagnetic valve, the third electromagnetic valve, the fourth electromagnetic valve and the pressure regulating valve through a CAN bus.

Compared with the prior art, the embodiment of the invention has the beneficial effects that: automatic emptying devices of battery package coolant liquid includes: the system comprises an air source pipeline, a first branch pipe, a second branch pipe, a third branch pipe, a fourth branch pipe, a bypass pipeline, an upper computer, a water cooling machine and a battery pack, wherein the water cooling machine and the battery pack are in communication connection with the upper computer; one end of the first branch pipe is communicated with the liquid inlet of the battery pack, and the other end of the first branch pipe is selectively communicated with the second branch pipe or the gas source pipeline; the second branch pipeline is communicated with a liquid outlet of the water cooling machine; one end of the third branch pipe is communicated with a liquid outlet of the battery pack, and the other end of the third branch pipe is selectively communicated with the fourth branch pipe or the bypass pipeline; the fourth branch pipe is communicated with a liquid return port of the water cooling machine; the bypass pipeline is communicated with a liquid storage port of the water cooling machine. When needs carry out flowing back operation, only need to close the pipeline between first branch road and the second branch road, and communicate the pipeline between first branch road and the air supply pipeline, close the pipeline between third branch road and the fourth branch road simultaneously, and switch on the pipeline between third branch road and the bypass pipeline, through the leading-in compressed air of air supply pipeline, thereby discharge the coolant liquid of battery package, and retrieve the liquid reserve tank of water-cooled generator, the automatic recycle of coolant liquid has been realized, whole flowing back process need not manual operation, simplify battery package coolant liquid flowing back operation.

In a second aspect, an embodiment of the present invention provides an automatic evacuation method for a coolant in a battery pack, which is performed based on the automatic evacuation device for a coolant in a battery pack of the first aspect, and specifically includes:

the water cooling machine responds to a stop instruction sent by the upper computer and is switched to a stop state;

when the water cooling machine finishes the switching of the stop states, the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed, and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be opened, so that compressed air is introduced through the air source pipeline to enter a battery pack liquid discharging process;

when the time length of the battery pack liquid discharging process reaches a preset first time length threshold value, the upper computer controls the first battery valve and the fourth electromagnetic valve to be opened, controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be closed, and ends the battery pack liquid discharging process.

As an improvement of the above scheme, after the water cooling machine is switched to the stop state in response to a stop command sent by the upper computer, the method further includes:

standing the water cooling machine, and monitoring the flow and the pressure of a liquid outlet of the water cooling machine;

judging whether the water-cooled machine meets any preset stop state switching condition; the stop state switching condition includes: the standing time of the water cooler reaches a preset second time threshold value, the flow of the liquid outlet of the water cooler is lower than a preset flow threshold value, the standing time of the water cooler reaches the preset second time threshold value, and the pressure of the liquid outlet of the water cooler is lower than a preset pressure threshold value;

if so, confirming that the water cooling machine completes the switching of the stop state;

if not, continuing to stand the water cooler.

As an improvement of the above scheme, the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed, and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be opened, and the method includes:

the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed and controls the second electromagnetic valve and the third electromagnetic valve to be opened;

and when the standing time reaches a preset third time threshold, the upper computer controls the pressure regulating valve to be opened.

As an improvement of the above scheme, the upper computer controls the first battery valve and the fourth electromagnetic valve to be opened, and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be closed, and the method includes:

the upper computer controls the pressure regulating valve to close;

and when the standing time reaches a preset fourth time threshold, the upper computer controls the second electromagnetic valve and the third electromagnetic valve to be closed and controls the first battery valve and the fourth electromagnetic valve to be opened.

Compared with the prior art, the embodiment of the invention has the beneficial effects that: based on the automatic emptying device for the battery pack cooling liquid, a water cooling machine responds to a stop instruction sent by an upper computer and is switched to a stop state; when the water cooling machine finishes the switching of the stop states, the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed, and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be opened, so that compressed air is introduced through the air source pipeline to enter a battery pack liquid discharging process; when the time length of the battery pack liquid discharging process reaches a preset first time length threshold value, the upper computer controls the first battery valve and the fourth electromagnetic valve to be opened, controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be closed, and ends the battery pack liquid discharging process. The whole battery pack liquid discharging process does not need manual operation, the liquid discharging operation of the battery pack cooling liquid is simplified, and meanwhile, the automatic recycling of the cooling liquid is realized.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic diagram of an automatic evacuation device for battery pack coolant according to an embodiment of the present invention;

fig. 2 is a flowchart of a method for automatically draining coolant from a battery pack according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example one

Referring to fig. 1, which is a schematic view of an automatic coolant evacuation device for a battery pack 9 according to an embodiment of the present invention, the automatic coolant evacuation device for a battery pack 9 includes: the device comprises an air source pipeline 1, a first branch pipe 2, a second branch pipe 3, a third branch pipe 4, a fourth branch pipe 5, a bypass pipeline 6, an upper computer 7, a water cooling machine 8 and a battery pack 9, wherein the water cooling machine 8 is in communication connection with the upper computer 7; one end of the first branch pipe 2 is communicated with a liquid inlet of the battery pack 9, and the other end of the first branch pipe is selectively communicated with the second branch pipe 3 or the gas source pipeline 1; the second branch pipeline is communicated with a liquid outlet of the water cooling machine 8; one end of the third branch pipe 4 is communicated with a liquid outlet of the battery pack 9, and the other end of the third branch pipe is selectively communicated with the fourth branch pipe 5 or the bypass pipeline 6; the fourth branch pipe 5 is communicated with a liquid return port of the water cooler 8; the bypass pipeline 6 is communicated with a liquid storage port of the water cooler 8.

When liquid is drained, the first branch pipe 2 is communicated with the air source pipeline 1, and meanwhile, the third branch pipe is communicated with the bypass pipeline 6.

Illustratively, the air supply line 1 is used for supplying compressed air. The upper computer 7 is used for controlling the first branch pipe 2 to be communicated with the second branch pipe 3 or the air source pipeline 1, and is also used for controlling the third branch pipe 4 to be communicated with the fourth branch pipe 5 or the bypass pipeline 6; and the upper computer 7 is provided with an AVL rack management system to control the switching of the pipelines.

Furthermore, a flow detection device can be arranged at the liquid outlet of the water-cooling machine to monitor the flow of the cooling liquid, or a pressure sensor is arranged at the liquid outlet of the water-cooling machine to monitor the pressure of the liquid outlet of the water-cooling machine.

The cooling liquid circulation heat dissipation principle of the battery pack 9 is as follows:

when the water-cooling machine 8 is in a working state, the first branch pipe 2 is communicated with the second branch pipe 3, the first pipe is not communicated with the air source pipeline 1, meanwhile, the third branch pipe 4 is communicated with the fourth branch pipe 5, the third branch pipe 4 is not communicated with the bypass pipeline 6, at the moment, the water-cooling machine 8 outputs cooling liquid in a liquid storage box of the water-cooling machine 8 from a liquid outlet at the lower position of the liquid storage box, inputs the cooling liquid into the battery pack 9 along the second branch pipe 3 and the first branch pipe 2, and flows back to the liquid storage box of the water-cooling machine 8 through the third branch pipe 4 and the fourth branch pipe 5, and the cooling liquid circulation loop is realized by repeating the processes, so that the heat of the battery pack 9 is radiated.

When the cooling liquid in the battery pack 9 needs to be drained, the specific principle is as follows:

when the liquid discharging function of the battery pack 9 is started, the upper computer 7 sends a stop instruction to the water cooling machine 8;

the water cooling machine 8 changes the self working state into a stop state in response to the received stop instruction;

after standing for 10s, the upper computer 7 judges the flow value/liquid outlet pressure reported by the water cooling machine 8, and when the flow value/liquid outlet pressure is lower than a set threshold value, the working state of the water cooling machine 8 is confirmed to be changed;

the upper computer 7 controls the first branch pipe 2 and the second branch pipe 3 to be not communicated, the first pipe is communicated with the gas source pipeline 1, meanwhile, the third branch pipe 4 is not communicated with the fourth branch pipe 5, the third branch pipe 4 is communicated with the bypass pipeline 6, and meanwhile, the gas source pipeline 1 is opened; at the moment, compressed air enters the battery pack 9 through the air source pipeline 1 and the first branch pipe 2, the cooling liquid in the battery pack is discharged, and the discharged cooling liquid flows back to the high-level liquid storage port of the liquid storage tank of the water-cooling machine 8 along the third branch pipe 4 and the bypass pipeline 6 and is stored in the liquid storage tank so as to be recycled next time.

In the whole liquid drainage process, only the pipeline switching between the second branch and the air source pipeline 1 and between the fourth branch and the bypass pipeline is controlled, compressed air can be introduced through the air source pipeline 1 to drain the cooling liquid of the battery pack 9 and is recycled to the liquid storage tank of the water cooler 8, the whole liquid drainage process does not need manual operation, the liquid drainage operation of the cooling liquid of the battery pack 9 is simplified, the leakage risk caused by manual operation liquid drainage is avoided, and the liquid drainage efficiency is improved; meanwhile, automatic recycling of cooling liquid is achieved, compared with manual liquid drainage, introduced impurities can be reduced, and the risk that the water cooler 8 and the battery pack 9 lose effectiveness due to impurity blockage is reduced.

In an alternative embodiment, the automatic coolant evacuation device for battery packs 9 further includes a first solenoid valve K1 and a second solenoid valve K2, the first solenoid valve K1 is disposed at an end of the second branch pipe 3 adjacent to the first branch pipe 2, and the second solenoid valve K2 is disposed at an end of the gas source pipe 1 adjacent to the first branch pipe 2.

In an alternative embodiment, the automatic coolant draining device for battery pack 9 further includes a third solenoid valve K3, a fourth solenoid valve K4, the third solenoid valve K3 is disposed at an end of the bypass pipe 6 adjacent to the third branch pipe 4, and the fourth solenoid valve K4 is disposed at an end of the fourth branch pipe 5 adjacent to the third branch pipe 4.

Further, the upper computer 7 is connected with the water cooling machine 8, the battery pack 9, the first electromagnetic valve K1, the second electromagnetic valve K2, the third electromagnetic valve K3 and the fourth electromagnetic valve K4 through a CAN bus.

In an alternative embodiment, the automatic coolant draining device for battery pack 9 further includes a pressure regulating valve K5, which is disposed on the air supply pipe 1.

Further, the upper computer 7 is connected with the pressure regulating valve K5 through a CAN bus.

Specifically, the pressure regulating valve K5 is located between the second electromagnetic valve K2 and the air inlet of the air source pipeline 1, and is used for regulating the flow rate of the input compressed air, so as to regulate the pipeline pressure, and the cooling liquid is discharged from the battery pack 9 through the pressure difference.

In an optional embodiment, the upper computer 7 is connected with the water cooling machine 8 and the battery pack 9 through a CAN bus.

For example, when the water cooling machine 8 is in a working state, the upper computer 7 controls the first electromagnetic valve K1 and the fourth electromagnetic valve K4 to be opened, and controls the second electromagnetic valve K2, the third electromagnetic valve K3 and the pressure regulating valve K5 to be closed, so that the air source pipeline 1 is closed, and a cooling liquid circulation loop formed by the water cooling machine 8, the second branch pipe 3, the first branch pipe 2, the battery pack 9, the third branch pipe 4 and the fourth branch pipe 5 is conducted to dissipate heat of the battery pack 9; when liquid drainage operation is required, the water cooling machine 8 is switched to a stop state, the first electromagnetic valve K1 and the fourth electromagnetic valve K4 are controlled to be closed, the second electromagnetic valve K2, the third electromagnetic valve K3 and the pressure regulating valve K5 are controlled to be opened, so that the air source pipeline 1 is opened, a cooling liquid drainage pipeline composed of the air source pipeline 1, the first branch pipe 2, the battery pack 9, the third branch pipe 4, the bypass pipeline 6 and the water cooling machine 8 is conducted, and cooling liquid in the battery pack 9 flows back to a liquid storage tank of the water cooling machine 8 for recycling.

Example two

The embodiment of the invention is different from the first embodiment in that a first three-way reversing valve is adopted to replace a first electromagnetic valve and a second electromagnetic valve; and a third electromagnetic valve and a fourth electromagnetic valve are replaced by a second third reversing valve. Specifically, the method comprises the following steps:

and a first interface of the first three-way reversing valve is communicated with the first branch pipe, a second interface of the first three-way reversing valve is communicated with the second branch pipe, and a third interface of the first three-way reversing valve is communicated with the gas source pipeline.

And a first interface of the second three-way reversing valve is communicated with the third branch pipe, a second interface of the second three-way reversing valve is communicated with the fourth branch pipe, and a third interface of the second three-way reversing valve is communicated with the bypass pipeline.

Furthermore, the upper computer is connected with the first three-way reversing valve and the second three-way reversing valve through a CAN bus.

When it is needed to be described, the working principle of the automatic emptying device of battery pack coolant in the second embodiment is the same as that in the first embodiment, and detailed description is omitted here.

Compared with the prior art, the embodiment of the invention has the beneficial effects that: the whole liquid drainage process does not need manual operation, the liquid drainage operation of the battery pack cooling liquid is simplified, the leakage risk caused by manual operation liquid drainage is avoided, and the liquid drainage efficiency is improved; meanwhile, automatic recycling of the cooling liquid is achieved, compared with manual liquid drainage, the requirements (such as air tightness and weight of a cooling circuit) for frequently replacing the cooling liquid and frequently confirming specific parameters of the battery pack can be avoided, introduced impurities are reduced, and the risk that the water cooler and the battery pack fail due to impurity blockage is reduced.

Example three

Referring to fig. 2, an embodiment of the present invention provides an automatic evacuation method for a coolant in a battery pack, which is performed by the automatic evacuation apparatus for a coolant in a battery pack according to the first embodiment, and specifically includes:

s1: the water cooling machine responds to a stop instruction sent by the upper computer and is switched to a stop state;

for example, the upper computer starts a battery pack liquid discharging function and sends a stopping instruction to the water cooling machine according to a liquid discharging instruction sent by a user side, or the upper computer responds to a touch operation of a user on a touch screen of the upper computer or a click operation of the user on an input device of the upper computer, starts the battery pack liquid discharging function and sends the stopping instruction to the water cooling machine. The AVL rack management system is installed on the upper computer and used for controlling the opening and closing of the first battery valve, the fourth electromagnetic valve, the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve so as to perform pipeline switching control.

S2: when the water cooling machine finishes the switching of the stop states, the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed, and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be opened, so that compressed air is introduced through the air source pipeline to enter a battery pack liquid discharging process;

s3: when the time length of the battery pack liquid discharging process reaches a preset first time length threshold value, the upper computer controls the first battery valve and the fourth electromagnetic valve to be opened, controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be closed, and ends the battery pack liquid discharging process.

In an optional embodiment, after the water cooling machine switches to the stop state in response to a stop command sent by the upper computer, the method further includes:

standing the water cooling machine, and monitoring the flow and the pressure of a liquid outlet of the water cooling machine;

judging whether the water-cooled machine meets any preset stop state switching condition; the stop state switching condition includes: the standing time of the water cooler reaches a preset second time threshold value, the flow of the liquid outlet of the water cooler is lower than a preset flow threshold value, the standing time of the water cooler reaches the preset second time threshold value, and the pressure of the liquid outlet of the water cooler is lower than a preset pressure threshold value;

if so, confirming that the water cooling machine completes the switching of the stop state;

if not, continuing to stand the water cooler.

Further, the first duration threshold value ranges from 1min to 2min, and preferably ranges from 2 min. The second duration threshold is 10 s.

As an improvement of the above scheme, the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed, and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be opened, and the method includes:

the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed and controls the second electromagnetic valve and the third electromagnetic valve to be opened;

and when the standing time reaches a preset third time threshold, the upper computer controls the pressure regulating valve to be opened.

As an improvement of the above scheme, the upper computer controls the first battery valve and the fourth electromagnetic valve to be opened, and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be closed, and the method includes:

the upper computer controls the pressure regulating valve to close;

and when the standing time reaches a preset fourth time threshold, the upper computer controls the second electromagnetic valve and the third electromagnetic valve to be closed and controls the first battery valve and the fourth electromagnetic valve to be opened.

Wherein the third time length threshold and the fourth time length threshold are 5 s.

The battery pack drainage principle of the embodiment of the invention is as follows:

the upper computer starts the liquid drainage function of the battery pack, and sends a stop instruction to the water cooling machine through the CAN bus to change the working state of the water cooling machine into a stop state.

And (4) after standing for 10s, judging the flow value/liquid outlet pressure reported by the water cooling machine by the upper computer, and confirming that the working state of the water cooling machine is changed.

The upper computer sends an electromagnetic valve control instruction through a CAN bus to control the operation as follows: and closing the first electromagnetic valve and the fourth electromagnetic valve to close the cooling liquid circulation channel of the water cooling machine, opening the second electromagnetic valve and the third electromagnetic valve, standing for 5s, and opening the pressure regulating valve to open the air source channel.

Standing for 2min, performing a liquid discharge process, closing the second electromagnetic valve and the third electromagnetic valve to close the air source channel, standing for 5s, then opening the first electromagnetic valve and the fourth electromagnetic valve, and finishing liquid discharge.

Compared with the prior art, the embodiment of the invention has the beneficial effects that: when the battery pack needs to drain liquid, the water cooling machine responds to a stop instruction sent by the upper computer and is switched to a stop state; when the water cooling machine finishes the switching of the stop states, the upper computer controls the first battery valve and the fourth electromagnetic valve to be closed, and controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be opened, so that compressed air is introduced through the air source pipeline to enter a battery pack liquid discharging process; when the time length of the battery pack liquid discharging process reaches a preset first time length threshold value, the upper computer controls the first battery valve and the fourth electromagnetic valve to be opened, controls the second electromagnetic valve, the third electromagnetic valve and the pressure regulating valve to be closed, and ends the battery pack liquid discharging process. The whole battery pack liquid discharging process does not need manual operation, the liquid discharging operation of the battery pack cooling liquid is simplified, the leakage risk caused by manual operation liquid discharging is avoided, and the liquid discharging efficiency is improved; meanwhile, automatic recycling of the cooling liquid is achieved, compared with manual liquid drainage, the requirements for frequently replacing the cooling liquid and frequently confirming specific parameters of the battery pack can be avoided, introduced impurities are reduced, and the risk that the water cooler and the battery pack are invalid due to impurity blockage is reduced.

It should be noted that the above-described device embodiments are merely illustrative, where the units described as separate parts may or may not be physically separate, and the parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. In addition, in the drawings of the embodiment of the apparatus provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, and may be specifically implemented as one or more communication buses or signal lines. One of ordinary skill in the art can understand and implement it without inventive effort.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.