Liquid cooling plate, battery pack, and temperature adjustment method therefor

Abstract

Disclosed in the present application are a liquid cooling plate, a battery pack, and a temperature adjustment method therefor. The liquid cooling plate comprises a housing, a partition plate, a suction device, and a cooling liquid. The housing has a cavity, and a liquid inlet and a liquid outlet in communication with the cavity; the partition plate is arranged in the cavity and divides the cavity into a plurality of accommodating cavities in communication with each other, each accommodating cavity being used for arranging a battery cell module, and the cooling liquid flowing in each accommodating cavity; the suction device is arranged on the partition plate and is in communication with two adjacent accommodating cavities; and the suction device is configured such that when the suction device is in an operating state, the cooling liquid circulates in the cavity and forms an internal circulation path.

Description

Liquid cooling plate, battery pack and temperature regulation method thereof

[0001] The present application claims priority to the Chinese patent application No. 202411134157.3, filed on August 16, 2024, and entitled "Liquid cooling plate, battery pack and temperature regulation method thereof", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of battery thermal management, and more particularly, to a liquid cooling plate, a battery pack and a temperature regulation method thereof. BACKGROUND

[0003] With the wide application of power batteries as a new type of core energy source in many fields such as new energy vehicles and aerospace, power batteries have gradually become a research hotspot. The performance of power batteries is obviously affected by temperature, especially for power batteries with high rate charging and discharging, which release high heat. Therefore, it is particularly important to manage the heat of power batteries.

[0004] At present, the semi-submerged cooling method can be used for power batteries with high rate charging and discharging, that is, part of the cell module of the power battery is submerged in the cooling liquid, and heat exchange is performed between the cooling liquid and the external circulation system to regulate the temperature of the power battery. However, the temperature difference between each cell of the current power battery is large, which affects the heat dissipation efficiency and service life of the power battery. SUMMARY

[0005] The purpose of the present application is to provide a liquid cooling plate, a battery pack and a temperature regulation method thereof, which can ensure the consistency of the temperature of each cell, avoid a large temperature difference between each cell of the power battery, and improve the heat dissipation efficiency and service life of the power battery.

[0006] In a first aspect, the embodiments of the present application provide a liquid cooling plate, comprising a shell, a partition plate, a suction device and a cooling liquid; the shell has a cavity and a liquid inlet and a liquid outlet communicating with the cavity; the partition plate is arranged in the cavity and divides the cavity into a plurality of accommodating cavities communicating with each other, each accommodating cavity is used for arranging a cell module, and the cooling liquid flows in each accommodating cavity; the suction device is arranged on the partition plate and communicates with two adjacent accommodating cavities; the suction device is configured to circulate the cooling liquid in the cavity and form an internal circulation path when the suction device is in a working state.

[0007] In some embodiments, each partition plate is provided with a first through hole and a second through hole, and the first through hole and the second through hole are located below the liquid level of the cooling liquid; the first through hole and the second through hole respectively communicate with two adjacent accommodating cavities, and the suction device is arranged at the first through hole.

[0008] In some embodiments, the suction device comprises a pump and a control valve; the pump is arranged on one side of the partition plate and communicates with the first through hole along the internal circulation path of the cooling liquid; the control valve is arranged at the first through hole and controls the communication between the first through hole and the pump.

[0009] In some embodiments, the control valve is configured as a solenoid valve, which comprises a valve seat, a valve core and a control assembly; the valve seat has a flow channel and a guide hole communicating therewith, one end of the flow channel communicates with the first through hole respectively, and the other end thereof communicates with the pump; the valve core is slidingly installed in the guide hole; the control assembly is configured to control the movement of the valve core along the guide hole; when the valve core is in a first position, the valve core seals the flow channel; and when the valve core is in a second position, the flow channel communicates with the first through hole.

[0010] In some embodiments, the shell comprises a box body and a cover plate; the partition plate is arranged in the box body and forms a plurality of the accommodation cavities, each of which is correspondingly provided with a fixing plate having a plug-in port matched with the battery cell module; the battery cell module passes through the plug-in port, the bottom of the battery cell module is located in the accommodation cavity, the top of the battery cell module is located outside the fixing plate, and the plug-in port and the battery cell module are sealed.

[0011] In some embodiments, the surface of the fixing plate is provided with a flow guide groove, and the flow guide groove communicates with the accommodation cavity.

[0012] In some embodiments, the liquid cooling plate further comprises a support frame and a flow guide pipe; the support frame is annularly arranged around each of the accommodation cavities, and the support frame is connected with the peripheral wall of the accommodation cavity and supports the fixing plate; the flow guide pipe is arranged below the support frame, and the support frame is provided with a flow guide hole communicating with the flow guide, one end of the flow guide pipe communicates with the flow guide hole, and the other end thereof communicates with the accommodation cavity.

[0013] Secondly, embodiments of this application also provide a battery pack, including multiple cell modules, a battery management unit, a temperature acquisition device, an external circulation system, and the liquid cooling plate described in the first aspect; the liquid cooling plate includes a cavity and an outlet and an inlet communicating with it, the outlet and inlet of the liquid cooling plate being connected to the external circulation system; a partition is provided in the cavity to form multiple independent and interconnected receiving cavities, and a suction device is provided between two adjacent receiving cavities; each cell module is correspondingly disposed in one receiving cavity, and the bottom of the cell module is immersed in the coolant; the temperature acquisition device is communicatively connected to the battery management unit, and the temperature acquisition device acquires the temperature of each cell module and transmits it to the battery management unit; the battery management unit is set with a preset temperature difference threshold, and when the temperature difference of the cell module is greater than the preset temperature difference threshold, the battery management unit controls the suction device to work, and the coolant circulates within the cavity, forming an internal circulation path.

[0014] In some embodiments, the battery cell module includes a plurality of spaced-apart battery cells; an upper spacer and a lower spacer; the upper spacer and the lower spacer are disposed between two adjacent battery cells, and the upper spacer is located at the top of the battery cell and seals the gap between two adjacent battery cells; the lower spacer is located at the bottom of the battery cell, and the gap is in communication with the coolant.

[0015] Thirdly, embodiments of this application also provide a method for regulating the temperature of a battery pack, comprising:

[0016] The battery management unit of the battery pack acquires the temperature of each cell in the cell module and calculates the temperature difference of the battery pack.

[0017] The battery management unit determines whether the temperature difference of the current battery pack is greater than its preset temperature difference threshold. If so, it controls the suction device to work, and the coolant circulates in the cavity to form an internal circulation path. If not, it continues to collect the temperature of each cell.

[0018] In some embodiments, the battery management unit has a preset warning temperature; the temperature regulation method for the battery pack further includes:

[0019] The battery management unit determines whether the current temperature of the battery pack is greater than the warning temperature; if so, it activates the external circulation system of the battery pack and the suction device.

[0020] If not, determine whether the temperature difference of the current battery pack is greater than its preset temperature difference threshold. If yes, control the suction device to work, and the coolant will circulate in the cavity to form an internal circulation path. If not, continue to collect the temperature of each cell.

[0021] The liquid cooling plate, the battery pack and the temperature adjusting method provided by the application, wherein a partition plate is arranged in the shell of the liquid cooling plate, the partition plate divides the cavity of the shell into multiple containing cavities, one battery cell module is arranged in each containing cavity, the partition plate is provided with a suction device, and the suction device is communicated with two adjacent containing cavities. When the battery management unit of the battery pack detects that the temperature difference of the battery pack is greater than a preset temperature difference threshold, the suction device is controlled to be in a working state, the suction device makes the cooling liquid flow between the two adjacent containing cavities, and then realizes the rapid circulation flow of the cooling liquid in the cavity and forms an internal circulation path.

[0022] In the related art, the liquid cooling plate is communicated with the external circulation system through the liquid inlet and the liquid outlet, so that the cooling liquid exchanges heat with the external circulation system, that is, the cooling liquid is externally circulated to control the temperature of the battery pack. However, the temperature difference between the battery cells in different regions of the battery pack cannot be effectively controlled, which affects the heat dissipation efficiency and service life of the power battery.

[0023] When the temperature difference between the battery cells in the battery pack is large, the suction device provided by the application can be started to accelerate the internal circulation speed of the cooling liquid, which not only improves the heat dissipation efficiency, but also helps to make the temperatures of the battery cells consistent and reduce the temperature difference of the battery pack, thereby improving the service life of the battery pack. BRIEF DESCRIPTION OF DRAWINGS

[0024] FIG. 1 is an exploded schematic view of the battery pack provided by the embodiment of the application;

[0025] FIG. 2 is a schematic view of the battery cell module arranged on the box provided by the embodiment of the application;

[0026] FIG. 3 is a structural schematic view of the box provided by the embodiment of the application;

[0027] FIG. 4 is a schematic view of the arrangement of the suction device in the containing cavity provided by the embodiment of the application;

[0028] FIG. 5 is a whole schematic view of the suction device provided by the embodiment of the application;

[0029] FIG. 6 is a schematic view of the internal structure of the suction device provided by the embodiment of the application;

[0030] FIG. 7 is an assembly schematic view of the support frame, the fixing plate and the flow guide pipe provided by the embodiment of the application;

[0031] FIG. 8 is an assembly schematic view of the support frame, the fixing plate and the flow guide pipe provided by the embodiment of the application;

[0032] FIG. 9 is a whole structural schematic view of the battery cell module provided by the embodiment of the application;

[0033] FIG. 10 is an exploded view of the battery cell module provided by the embodiment of the application;

[0034] FIG. 11 is a flowchart of a temperature adjustment method of a battery pack according to an embodiment of the present application;

[0035] FIG. 12 is a flowchart of a temperature adjustment method of a battery pack according to an embodiment of the present application.

[0036] Legend: 10-liquid cooling plate; 11-box body; 111-liquid inlet pipe; 112-liquid outlet pipe; 12-cover plate; 13-baffle; 131-first through hole; 132-second through hole; 14-suction device; 141-pump; 142-control valve; 1421-valve seat; 1422-valve core; 1423-guide hole; 1424-spring; 1425-iron core; 1426-controller; 15-fixing plate; 151-flow guide groove; 16-support frame; 17-flow guide pipe; 18-sealing ring; 20-battery cell module; 21-battery cell; 22-upper spacer; 23-lower spacer; 24-end plate; 100-battery pack. DETAILED DESCRIPTION

[0037] The embodiments of the present application are described in detail below with reference to the accompanying drawings. The embodiments described below are examples for explaining the present application and should not be understood as limiting the present application.

[0038] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0039] As described in the background, the temperature difference between the battery cells of the current power battery is large, which affects the heat dissipation efficiency and service life of the power battery. The inventor found that the reason for this problem is that the liquid cooling plate in the related art is connected to the external circulation system through the liquid inlet and the liquid outlet to exchange heat between the cooling liquid and the external circulation system, i.e., through external circulation of the cooling liquid to control the temperature of the battery pack. However, this method cannot effectively control the temperature difference between the battery cells in different regions of the battery pack, which affects the heat dissipation efficiency and service life of the power battery.

[0040] To solve the above technical problems, the embodiment of the present application provides a liquid cooling plate. The liquid cooling plate is internally provided with a suction device, and the suction device is located between two adjacent containing cavities. When the battery management unit of the battery pack detects that the temperature difference of the battery pack is greater than a preset temperature difference threshold, the suction device is controlled to be in a working state, and the suction device makes the cooling liquid flow between the two adjacent containing cavities, so as to realize rapid circulation of the cooling liquid in the cavity and form an internal circulation path.

[0041] In this way, when the temperature difference between each battery cell of the battery pack is large, the suction device can be started to accelerate the internal circulation speed of the cooling liquid, thereby improving the heat dissipation efficiency and facilitating the temperature of each battery cell to be consistent, reducing the temperature difference of the battery pack, and thereby prolonging the service life of the battery pack.

[0042] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present application more apparent and easy to understand, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0043] As shown in FIGS. 1-3, the liquid cooling plate 10 provided by the embodiments of the present application is used for heat exchange of the battery pack 100. The liquid cooling plate 10 has cooling liquid therein, which can be high-temperature-resistant insulating cooling liquid. The battery cell module 20 of the battery pack 100 is partially immersed in the cooling liquid, for example, along the height direction of the battery cell module 20, the battery cell module 20 is semi-immersed in the cooling liquid.

[0044] Specifically, the liquid cooling plate 10 includes a shell, a partition plate 13 and a suction device 14, wherein the shell can be a regular shell, for example, the shell is configured as a rectangular shell, and this embodiment is taken as an example for description. The shell has a rectangular cavity, and the side wall of the shell is provided with an inlet and an outlet which are in communication with the cavity, and the inlet and the outlet are in communication with the external circulation system of the battery pack 100 through the inlet and the outlet, so that the cooling liquid exchanges heat with the external circulation system.

[0045] For example, the side wall of the shell is provided with an inlet pipe 111 and an outlet pipe 112, the inlet pipe 111 is in communication with the inlet, and the outlet is in communication with the outlet pipe 112, and the liquid cooling plate 10 is in communication with the external circulation system through the inlet pipe 111 and the outlet pipe 112, respectively. The external circulation system at least includes a circulation pipeline, a circulation pump and a heat exchanger arranged on the circulation pipeline. The circulation pump is used to suck the cooling liquid to flow in the circulation pipeline and exchange heat with the heat exchanger.

[0046] Further, the partition plate 13 is arranged in the shell, a bottom surface of the partition plate 13 is connected with a bottom of the shell, and the cavity is divided into a plurality of containing cavities in communication, and the cooling liquid flows in each containing cavity. For example, the liquid cooling plate 10 includes two partition plates 13, the two partition plates 13 are arranged in a cross shape in the rectangular shell, and the cavity is divided into four containing cavities, and two adjacent containing cavities are isolated by the partition plate 13.

[0047] As shown in FIG. 4, the suction device 14 is arranged on the partition plate 13, and the suction device 14 is in communication with two adjacent containing cavities respectively, that is, at least one suction device 14 is arranged in each two adjacent containing cavities. When the suction device 14 is in the working state, it can suck the cooling liquid in one containing cavity into another containing cavity, so as to accelerate the flow of the cooling liquid in the two adjacent containing cavities.

[0048] It can be understood that, by arranging the suction device 14 at different positions of the partition plate 13, the cooling liquid can flow in a certain direction between the containing cavities and form an internal circulation path, which can be clockwise or counterclockwise, and the present application does not limit this. Preferably, the suction direction of the suction device 14 is consistent with the flow direction of the cooling liquid from the liquid inlet to the liquid outlet, so as to accelerate the flow of the cooling liquid in the cavity.

[0049] Further, when the temperature difference between each battery cell 21 in the battery pack 100 (the difference between the highest temperature and the lowest temperature) is large, and the temperature difference between each battery cell in the battery pack 100 is greater than a preset temperature difference threshold, the suction device 14 is controlled to be in the working state, so as to accelerate the circulation of the cooling liquid in the cavity. Otherwise, the cooling liquid circulates in the cavity at a normal speed.

[0050] In the related art, the liquid cooling plate is in communication with the external circulation system through the liquid inlet and the liquid outlet, so that the cooling liquid exchanges heat with the external circulation system, that is, the cooling liquid circulates outside to control the temperature of the battery pack. However, the temperature difference between the battery cells in different regions of the battery pack cannot be effectively controlled, which affects the heat dissipation efficiency and service life of the power battery.

[0051] The liquid cooling plate 10 provided by the present application can start the suction device 14 to accelerate the internal circulation speed of the cooling liquid when the temperature difference between each battery cell 21 in the battery pack 100 is large, which not only improves the heat dissipation efficiency, but also helps to make the temperature of each battery cell 21 consistent, reduces the temperature difference between each battery cell in the battery pack 100, and improves the service life of the battery pack 100.

[0052] Referring to FIG. 3, each of the partitions 13 is provided with a first through hole 131 and a second through hole 132, which are arranged at intervals along the extension direction of the partition 13. The first through hole 131 and the second through hole 132 are both located below the liquid level of the cooling liquid, and the first through hole 131 and the second through hole 132 respectively communicate between two adjacent accommodating cavities; that is, the cooling liquid flows between the two adjacent accommodating cavities through the first through hole 131 and the second through hole 132.

[0053] As shown in FIGS. 5 and 6, the suction device 14 is arranged at the first through hole 131 in the embodiment of the application, and the first through hole 131 can be a rectangular hole. The suction device 14 includes a pump 141 and a control valve 142, wherein the pump 141 and the control valve 142 are respectively signal connected with the battery management unit of the battery pack 100, that is, the battery management unit controls the suction device 14 to work according to the temperature state of the battery cell module 20.

[0054] Specifically, along the internal circulation path of the cooling liquid, the pump 141 is arranged at one side of the partition 13, and the pump 141 is in communication with the first through hole 131. The control valve 142 is arranged at the first through hole 131 and can control the communication between the first through hole 131 and the pump 141. The control valve 142 is configured as a solenoid valve, and the pump 141 is configured as a pipeline pump. The control valve 142 includes a valve seat 1421, a valve core 1422 and a control assembly. The valve seat 1421 has a flow channel and a guide hole 1423 in communication therewith. The guide hole 1423 is arranged vertically with the flow channel, and one end of the flow channel is in communication with the first through hole 131, and the other end is in communication with the pipeline pump.

[0055] For example, a pipeline pump is installed on one side of the control valve 142 by screwing. The outer diameter of the pipeline pump is the same as the inner diameter of the flow channel of the valve seat 1421, and the pipeline pump is wrapped with a rubber band at the connection position with the flow channel, which can play a sealing, fixing and anti-corrosion role.

[0056] The valve core 1422 in the embodiment of the application is slidingly installed in the guide hole 1423 and can move vertically along the guide hole 1423. The control assembly is configured to control the movement of the valve core 1422 along the guide hole 1423; when the valve core 1422 is in a first position, the valve core 1422 seals the flow channel, and when the valve core 1422 is in a second position, the flow channel is in communication with the first through hole 131.

[0057] Further, the control assembly can include a controller 1426, an electromagnetic coil (not shown), an iron core 1425, and a spring 1424, wherein the spring 1424 is arranged between the iron core 1425 and the valve core 1422, the controller 1426 is in signal connection with the battery management unit, and the controller 1426 controls the electromagnetic coil to be electrified and generate a magnetic field, the iron core 1425 is pressed against the spring 1424 and overcomes the elastic force of the spring 1424 under the action of the magnetic field, so that the valve core 1422 moves along the guide hole 1423 to the first position, and the valve core 1422 seals the flow passage.

[0058] Conversely, the controller 1426 changes the current direction of the electromagnetic coil, and the iron core 1425 can drive the spring 1424 to return to the initial state and drive the valve core 1422 to move reversely along the guide hole 1423 under the action of the magnetic field, and when the valve core 1422 moves to the second position, the sealing of the flow passage is released, and the first through hole is in communication with the pipeline pump.

[0059] On the basis of the above-mentioned embodiments, the shell is configured in a split structure in the embodiments of the present application, the shell includes a box body 11 and a cover plate 12, the cover plate 12 is arranged at the top opening of the box body 11, and a sealing ring 18 is arranged at the combined position between the cover plate 12 and the box body 11, and the sealing ring 18 is configured as an annular sealing ring. In this way, the sealing property of the battery pack 100 can be ensured, dust, water vapor and the like are effectively prevented from entering the battery pack 100 to cause damage to the internal devices, the unevenness of the contact surface can be compensated, and the stability of the entire battery pack 100 can be ensured.

[0060] Further, two partitions 13 are arranged in the box body 11, the two partitions 13 are arranged in a cross shape, the bottom side of the partition 13 is welded to the bottom of the box body 11, and the end of the partition 13 is welded to the side wall of the box body 11, so that four mutually independent accommodating cavities are formed in the box body 11, and the four accommodating cavities are communicated through the second through hole 132 arranged on the partition 13.

[0061] As shown in FIGS. 7 and 8, and in combination with FIG. 2, each accommodating cavity is used for mounting one battery cell module 20 in the embodiments of the present application, and in order to facilitate the sealed installation of the battery cell module 20 in the accommodating cavity, a fixed plate 15 is further arranged for each accommodating cavity in the embodiments of the present application, and the fixed plate 15 is provided with a plug-in mounting port matched with the battery cell module 20. The fixed plate 15 is an annular plate, and the fixed plate 15 is arranged at the top opening of the accommodating cavity and is fixed. The battery cell module 20 is plug-in mounted in the accommodating cavity through the plug-in mounting port, and the battery cell module 20 and the plug-in mounting port are sealed. The bottom of the battery cell module 20 is immersed in the cooling liquid, and the top of the battery cell module 20 is located above the fixed plate 15, that is, the battery cell module 20 is half-immersed in the cooling liquid.

[0062] Further, the fixing plate 15 provided in the embodiment of the present application has a surface provided with a flow guide groove 151, the flow guide groove 151 can extend to a corner of the fixing plate 15, the corner of the fixing plate 15 is provided with a through hole, the through hole is in communication with the flow guide groove 151 and the accommodating cavity, so that the cooling liquid overflowing from the gap between the battery cell module 20 and the plug-in port in the harsh working condition can further flow back to the accommodating cavity through the flow guide groove 151, so as to ensure the capacity of the cooling liquid in the liquid cooling plate 10.

[0063] In order to facilitate the fixing plate 15 to be arranged around the top opening of the accommodating cavity, the liquid cooling plate 10 provided in the embodiment of the present application further comprises a support frame 16, the support frame 16 is arranged around the inner wall of the accommodating cavity. The support frame 16 is annular and arranged around the top opening of the accommodating cavity. The support frame 16 is located below the fixing plate 15, and the fixing plate 15 can be attached to the support frame 16, and a positioning structure is arranged between the two to facilitate the positioning of the fixing plate 15 and the support frame 16.

[0064] For example, the support frame 16 is welded to the side wall of the box 11 and the side wall of the beam, the support frame 16 has a limiting groove arranged around the surface thereof, the bottom of the fixing plate 15 has a protrusion matched with the limiting groove, and the support frame 16 is embedded in the limiting groove through the protrusion at the top thereof, so as to realize the positioning of the support frame 16 and the fixing plate 15. In this way, the connection between the fixing plate 15 and the support frame 16 is more stable. It can be understood that the fixing plate 15 and the support frame 16 are further fixed by bolts in the embodiment of the present application, which improves the installation stability of the fixing plate 15 and effectively prevents the leakage of cooling liquid caused by bumpy road conditions.

[0065] Further, the corner of the support frame 16 is provided with a flow guide hole and a flow guide pipe 17 in the embodiment of the present application, wherein the flow guide pipe 17 is perpendicular to the bottom plate of the box 11, the top end of the flow guide pipe 17 is connected with the support frame 16 and is in communication with the flow guide hole, and the other end of the flow guide pipe 17 is in communication with the accommodating cavity.

[0066] For example, the bottom end of the flow guide pipe 17 is welded to the bottom of the box 11, and the pipe wall of the flow guide pipe 17 is provided with a through hole in communication with the accommodating cavity; or the flow guide pipe 17 is in communication with the accommodating cavity through the bottom opening thereof, which is not limited in the embodiment of the present application. It should be noted that the fixing plate 15 is provided with a through hole in communication with the flow guide groove 151, and the through hole is in communication with the flow guide hole and the flow guide pipe 17, thereby realizing the communication between the flow guide groove 151 and the accommodating cavity.

[0067] The embodiment of the present application also provides a battery pack 100, which comprises a plurality of battery cell modules 20, a battery management unit, a temperature acquisition device, an external circulation system and a liquid cooling plate 10, wherein the liquid cooling plate 10 comprises a cavity and a partition plate 13 arranged in the cavity, the partition plate 13 divides the cavity into a plurality of accommodating cavities, and a suction device 14 is arranged between two adjacent accommodating cavities.

[0068] The plurality of battery cell modules 20 are respectively arranged in the plurality of accommodating cavities, and at least one battery cell module 20 is arranged in each accommodating cavity. The bottom of the battery cell module 20 is immersed in the cooling liquid, and the top of the battery cell module 20 is located outside the accommodating cavity, that is, the battery cell module 20 is semi-immersed in the cooling liquid.

[0069] The temperature collection device includes a plurality of temperature sensors, and the plurality of temperature sensors are respectively arranged on the battery cell modules 20, and at least one temperature sensor is arranged on each battery cell module 20. Preferably, a plurality of temperature sensors are arranged on the battery cell module 20, and the plurality of temperature sensors are arranged on the battery cells 21 located at the corners and the middle position of the battery cell module 20.

[0070] Further, the temperature collection device collects the temperature of each battery cell 21 and transmits it to the battery management unit. The battery management unit is provided with a preset temperature difference threshold value. The battery management unit calculates the actual temperature difference of the battery pack 100 according to the temperature of each battery cell 21, and when the actual temperature difference is greater than the preset temperature difference threshold value, the battery management unit controls the suction device 14 to be in a working state, that is, controls the valve 142 to be in an open state and the pump to start sucking the cooling liquid. The cooling liquid circulates in the cavity and forms an internal circulation path.

[0071] In this way, the internal circulation speed of the cooling liquid is accelerated, which not only improves the heat dissipation efficiency, but also helps to make the temperatures of the battery cells 21 consistent and reduce the temperature difference of the battery pack, thereby prolonging the service life of the battery pack.

[0072] As shown in FIGS. 9 and 10, the battery cell module 20 in the embodiment of the application includes two end plates 24 and a plurality of battery cells 21 arranged between the two end plates 24, and the plurality of battery cells 21 are arranged at intervals. An upper spacer 22 and a lower spacer 23 are arranged between adjacent two battery cells 21. The upper spacer 22 is located at the top of the battery cell 21, and the upper spacer 22 seals the gap between the adjacent two battery cells 21. The lower spacer 23 is located at the bottom of the battery cell 21, and the lower spacer 23 is arranged in parallel with the upper spacer 22, so that the adjacent two battery cells 21 form a gap in communication with the cooling liquid.

[0073] It can be understood that the upper spacer 22 and the lower spacer 23 are also arranged between the end plate 24 and the battery cell 21, and are connected by the spacers. The end plate 24 is fixedly connected to the bottom plate of the box body 11 by bolts. Further, the upper spacer 22 and the lower spacer 23 can be arranged with double-sided adhesive tape, aerogel, foam and other heat-insulating and flame-retardant materials according to actual needs. The above spacers play a role in safety protection and delay of heat runaway spread, and enable the cooling liquid to directly flow through the large surface of the battery cell 21 to quickly take away heat, thereby improving the heat dissipation effect of the battery pack 100. At the same time, the upper spacer 22 prevents the cooling liquid from overflowing through the gap between the two battery cells 21.

[0074] As shown in FIG. 11, the embodiment of the present application provides a temperature regulation method of a battery pack, comprising the following steps:

[0075] Step S100: the battery management unit of the battery pack 100 acquires the temperature of each battery cell 21 of the battery cell module 20 and calculates the temperature difference of the battery pack 100.

[0076] Specifically, a plurality of temperature sensors are arranged on the battery cell module 20, which can collect the temperature of the battery cell 21 in real time or at a certain preset interval time. The temperature sensors are signal connected with the battery management unit and transmit the collected temperature of each battery cell 21 to the battery management unit.

[0077] Further, the battery management unit receives the actual temperature of each battery cell 21 and calculates the temperature difference between the highest temperature and the lowest temperature of the battery pack 100.

[0078] Step S210: the battery management unit determines whether the temperature difference of the current battery pack 100 is greater than the preset temperature difference threshold value, if yes, step S220 is executed: the suction device 14 is controlled to work, and the cooling liquid circulates in the cavity and forms an internal circulation path; if not, step S230 is executed: the temperature of each battery cell module 20 is continuously collected.

[0079] Specifically, the battery management unit has a preset temperature difference threshold value, for example, the preset temperature difference threshold value is 5-8℃, which is not limited in the embodiment of the present application. If the temperature difference of the current battery pack 100 is greater than the preset temperature difference threshold value, the battery management unit controls the suction device 14 to work, that is, the battery management unit controls the electromagnetic valve and the pipeline pump signal connected therewith to open the electromagnetic valve and the pipeline pump is in working state. At this time, under the action of the suction device 14, the cooling liquid circulates rapidly in the cavity and forms an internal circulation path.

[0080] On the contrary, if the temperature difference of the current battery pack 100 is less than the preset temperature difference threshold value, the suction device 14 does not work, and the cooling liquid flows normally in the cavity, at the same time, the temperature sensor continues to collect the temperature of each battery cell 21 and uploads it to the battery management unit.

[0081] The temperature regulation method of the battery pack 100 provided by the embodiment of the present application can start the suction device 14 to speed up the internal circulation speed of the cooling liquid when the temperature difference between each battery cell 21 in the battery pack 100 is large, which not only improves the heat dissipation efficiency, but also helps the temperature of each battery cell 21 to be consistent and reduces the temperature difference of the battery pack 100, thereby prolonging the service life of the battery pack 100.

[0082] As shown in FIG. 12, on the basis of the above embodiment, the temperature regulation method provided by the embodiment of the present application further comprises:

[0083] Step S310: The battery management unit determines whether the temperature of the current battery pack 100 is greater than the pre-warning temperature; if yes, step S320 is executed: the outer circulation system and the suction device 14 of the battery pack 100 are started;

[0084] If no, step S210 is executed: it is determined whether the temperature difference of the current battery pack 100 is greater than the preset temperature difference threshold; if yes, the suction device 14 is controlled to work, and the coolant circulates in the cavity to form an inner circulation path; if no, the temperature of each battery cell 21 is continuously collected.

[0085] Specifically, the battery management unit is preset with a pre-warning temperature. When the temperature of the battery cell 21 exceeds the pre-warning temperature, the battery pack 100 is prone to thermal runaway. Therefore, not only the flow speed of the coolant in the battery pack 100 needs to be accelerated, but also the heat exchange between the coolant and the outer circulation system is needed to quickly adjust the temperature of the battery pack 100.

[0086] When the battery management unit determines that the temperature of the current battery pack 100 is greater than the pre-warning temperature, the battery management unit starts the circulation pump of the outer circulation system and the suction device 14, so that the coolant flows in the battery pack 100 at a high speed, and the heat exchanger of the outer circulation system exchanges heat with the coolant, thereby cooling or heating the coolant, so that the coolant can quickly adjust the temperature of the battery cell 21 to avoid thermal runaway of the battery pack 100.

[0087] Conversely, when the battery management unit determines that the temperature of the current battery pack 100 is less than the pre-warning temperature, the battery management unit executes the above step S210, which will not be described here.

[0088] In this way, when the temperature of the battery pack 100 exceeds the pre-warning temperature, the outer circulation system and the inner circulation speed of the coolant can be started at the same time, so that the temperature of the battery pack 100 can be effectively adjusted to avoid thermal runaway of the battery pack 100.

[0089] In the description of the present specification, the description referring to the terms "embodiment", "example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0090] Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and purposes of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A liquid-cooled plate, characterized in that, The liquid cooling plate comprises a shell, a partition plate, a suction device and a cooling liquid; The shell has a cavity and a liquid inlet and a liquid outlet connected with the cavity; The partition plate is arranged in the cavity and divides the cavity into a plurality of accommodating cavities in communication with each other, each of the accommodating cavities is used for arranging a battery cell module, and the cooling liquid flows in each of the accommodating cavities; The suction device is arranged on the partition plate and communicates with two adjacent accommodating cavities; when the suction device is in a working state, the cooling liquid circulates in the cavity and forms an internal circulation path.

2. The liquid cold plate of claim 1, wherein, Each of the partition plates is provided with a first through hole and a second through hole, and the first through hole and the second through hole are located below the liquid level of the cooling liquid; The first through hole and the second through hole respectively communicate with two adjacent accommodating cavities, and the suction device is arranged at the first through hole.

3. The liquid cold plate of claim 2, wherein, The suction device comprises a pump and a control valve; Along the internal circulation path of the cooling liquid, the pump is arranged on one side of the partition plate and communicates with the first through hole; The control valve is arranged at the first through hole and controls the communication between the first through hole and the pump.

4. The liquid cold plate of claim 3, wherein, The control valve is configured as a solenoid valve, and the control valve comprises a valve seat, a valve core and a control assembly; The valve seat has a flow channel and a guide hole connected with the flow channel, one end of the flow channel communicates with the first through hole, and the other end of the flow channel communicates with the pump; The valve core is slidably installed in the guide hole, the control assembly is configured to control the movement of the valve core along the guide hole, and when the valve core is in a first position, the valve core seals the flow channel; and when the valve core is in a second position, the flow channel communicates with the first through hole.

5. The liquid cold plate of any of claims 1 to 4, wherein, The shell comprises a box body and a cover plate; The partition plate is arranged in the box body and forms a plurality of accommodating cavities, each of the accommodating cavities is provided with a fixing plate corresponding thereto, and the fixing plate has a plug-in port matched with the battery cell module; The battery cell module penetrates the plug-in port, the bottom of the battery cell module is located in the accommodating cavity, the top of the battery cell module is located outside the fixing plate, and the plug-in port and the battery cell module are sealed.

6. The liquid cold plate of claim 5, wherein, The surface of the fixing plate is provided with a flow guide groove, and the flow guide groove communicates with the accommodating cavity.

7. The liquid cold plate of claim 6, wherein, The liquid cooling plate further comprises a support frame and a flow guide pipe; The support frame is annularly arranged around each of the accommodating cavities, and the support frame is connected with the peripheral wall of the accommodating cavity and supports the fixing plate; The flow guide pipe is arranged below the support frame, and the support frame is provided with a flow guide hole in communication with the flow guide pipe, one end of the flow guide pipe communicates with the flow guide hole, and the other end of the flow guide pipe communicates with the accommodating cavity.

8. A battery pack, characterized by, The liquid cooling plate comprises a plurality of battery cell modules, a battery management unit, a temperature acquisition device, an external circulation system and the liquid cooling plate according to any one of claims 1 to 7; The liquid cooling plate comprises a cavity and a liquid outlet and a liquid inlet connected with the cavity, and the liquid outlet and the liquid inlet of the liquid cooling plate communicate with the external circulation system; The cavity is provided with a partition plate to form a plurality of independent and communicating accommodating cavities, and a suction device is arranged between two adjacent accommodating cavities; Each of the battery cell modules is arranged in one of the accommodating cavities, and the bottom of the battery cell module is immersed in the cooling liquid; The temperature collecting device is in communication connection with the battery management unit, and the temperature collecting device collects the temperature of each battery cell module and transmits to the battery management unit; The battery management unit is provided with a preset temperature difference threshold, and when the temperature difference of the battery cell module is greater than the preset temperature difference threshold, the battery management unit controls the suction device to work, and the cooling liquid circulates in the cavity and forms an internal circulation path.

9. The battery pack of claim 8, wherein, The battery cell module comprises a plurality of spaced battery cells, an upper spacer and a lower spacer. The upper spacer is located at the top of the battery cell and seals the gap between the two adjacent battery cells. The lower spacer is located at the bottom of the battery cell, and the gap is in communication with the cooling liquid.

10. A method of temperature regulation for a battery pack as claimed in claim 8 or 9, characterized in that, Comprise: The battery management unit of the battery pack acquires the temperature of each battery cell of the battery cell module and calculates the temperature difference of the battery pack; The battery management unit judges whether the temperature difference of the current battery pack is greater than its preset temperature difference threshold, if yes, controls the suction device to work, and the cooling liquid circulates in the cavity and forms an internal circulation path; if not, continue to collect the temperature of each battery cell. 11.The method of Claim 10, wherein, The battery management unit is preset with a warning temperature; The temperature regulation method of the battery pack further comprises: The battery management unit judges whether the temperature of the current battery pack is greater than the warning temperature; if yes, the external circulation system of the battery pack and the suction device are started; If not, judge whether the temperature difference of the current battery pack is greater than its preset temperature difference threshold, if yes, control the suction device to work, and the cooling liquid circulates in the cavity and forms an internal circulation path; if not, continue to collect the temperature of each battery cell.

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