A Thermal Management Method, Device and System for Energy Power Batteries

Abstract

The present invention discloses an energy power battery thermal management method, device and system, including: real-time monitoring the temperature of the first battery cell of the power battery, when the temperature of the first battery cell exceeds the preset working range, releasing the first supercritical working fluid in the accumulator and inputting it into the working pipeline, and starting the semiconductor sheet to process the working fluid in the working fluid storage tank into the second supercritical working fluid; inputting the second supercritical working fluid into the working pipeline, the first supercritical working fluid and the second supercritical working fluid enter the shunt channel successively after being input into the working pipeline, and output the third supercritical working fluid through the shunt channel and enter the battery module; after the third supercritical working fluid enters the battery module, monitoring the temperature of the second battery cell of the power battery, and stopping the input of the third supercritical working fluid when the temperature of the second battery cell returns to the preset working range. The present invention can improve the working efficiency of the power battery thermal management system on the basis of energy conservation and energy storage.

Description

Technical Field

[0001] The present invention relates to the technical field of energy and power, and particularly to a thermal management method, device and system for an energy power battery. Background Art

[0002] A power battery is a power source that provides power for tools, mostly referring to a storage battery that provides power for electric vehicles, electric trains, electric bicycles and golf carts. In traditional technologies, new energy vehicle power batteries face many challenges, such as the active power loss of lithium iron phosphate at low temperatures, and the driving range drops by about 50% at about minus 20 degrees Celsius; there are also thermal runaway safety problems. When the heat accumulated in the battery far exceeds the surface heat dissipation, it is easy to cause an internal short circuit of the battery, and a gas fire and a serious explosion will occur within a few minutes.

[0003] In the prior art, for dealing with the battery heating situation, liquid cooling is the most commonly used heat dissipation method. For low temperatures in winter, a heating film is often used for heating. Both of these methods have the problems of low efficiency and large battery consumption, which greatly affect the driving range of electric vehicles. Summary of the Invention

[0004] Embodiments of the present invention provide a thermal management method, device and system for an energy power battery, which can realize the refrigeration and preheating functions of the power battery on the basis of energy conservation and energy storage, improve the working efficiency of the power battery thermal management system, and extend the service life of the power battery.

[0005] An embodiment of the present invention provides a thermal management method for an energy power battery, including:

[0006] Real-time monitoring of the temperature of the first battery cell of the power battery. When the temperature of the first battery cell exceeds the preset working range, the first supercritical working medium in the accumulator is released and input into the working pipeline, and the semiconductor chip is started to process the working medium in the working medium storage tank into a second supercritical working medium; wherein, the first supercritical working medium is the supercritical working medium that entered the accumulator through the branch circuit in the working pipeline in the previous working cycle;

[0007] Input the second supercritical working medium into the working pipeline. After the first supercritical working medium and the second supercritical working medium are input into the working pipeline, they enter the shunt channel successively, and the third supercritical working medium is output through the shunt channel and enters the battery module; wherein, after the second supercritical working medium is input into the working pipeline, it is shunted. The shunted second supercritical working medium flows into the shunt channel and the branch circuit respectively, and the second supercritical working medium passing through the branch circuit enters the accumulator;

[0008] After the third supercritical working medium enters the battery module, monitor the temperature of the second battery cell of the power battery. When the temperature of the second battery cell returns to the preset working range, stop the input of the third supercritical working medium.

[0009] Compared with the prior art, a thermal management method for an energy power battery disclosed in an embodiment of the present invention stores supercritical working fluid in an accumulator first. When the battery needs to be cooled or preheated, the stored working fluid is released first, laying a foundation for the subsequent supercritical working fluid in the working fluid storage tank to further adjust the temperature of the power battery, thereby improving the working efficiency of the thermal management system.

[0010] Further, the method for monitoring the temperature of the battery cells in real time, when the temperature of the first battery cell exceeds the preset working range, releasing the first supercritical working fluid in the accumulator into the working pipeline, specifically includes:

[0011] Obtaining a first temperature at the positive electrode tab on the surface of the battery cell of the power battery, and simultaneously obtaining a second temperature at the bottom of the battery cell of the same cross-section;

[0012] Recording the first temperature and the second temperature, and simultaneously calculating the difference between the two. When one of the first temperature and the second temperature exceeds the preset temperature threshold or the difference exceeds the preset temperature difference threshold, releasing the first supercritical working fluid in the accumulator into the working pipeline.

[0013] Further, for inputting the second supercritical working fluid into the working pipeline, after the first supercritical working fluid and the second supercritical working fluid are input into the working pipeline, they successively pass through a shunt channel, and a third supercritical working fluid is output through the shunt channel and enters the battery module, specifically including:

[0014] Monitoring the state of the second supercritical working fluid by using a working fluid pressure sensor and a working fluid temperature sensor in the working fluid storage tank. When it is monitored that the second supercritical working fluid reaches the working state, starting the gas-liquid pump and inputting the second supercritical working fluid into the working pipeline;

[0015] After the first supercritical working fluid and the second supercritical working fluid are input into the working pipeline, they enter the shunt channel successively through the inlet gears of the shunt channel; wherein, the shunt channel is connected to several pipelines in the battery module;

[0016] After the first supercritical working fluid and the second supercritical working fluid enter the shunt channel, a third supercritical working fluid is output through the shunt channel, and the third supercritical working fluid enters several pipelines in the battery module respectively; wherein, a part of the second supercritical working fluid enters a branch circuit after being input into the working pipeline, and the branch circuit is connected to the accumulator. When the part of the second supercritical working fluid enters the accumulator, it becomes the first supercritical working fluid; when the accumulator pressure sensor in the accumulator monitors that the accumulator is full of working fluid, stopping inputting the supercritical working fluid from the branch circuit into the accumulator.

[0017] By setting up a flow - splitting channel, the supercritical working fluid can enter the battery module evenly to work. A branch circuit is designed to replenish part of the supercritical working fluid in the working - fluid storage tank back into the accumulator, saving energy and laying a foundation for the next working condition startup.

[0018] Furthermore, after the third supercritical working fluid enters the battery module, the temperature of the second battery cell of the power battery is monitored. When the temperature of the second battery cell returns to the preset working range, the input of the third supercritical working fluid is stopped. Specifically, it includes:

[0019] After the third supercritical working fluid enters several pipelines of the battery module, the temperature of the second battery cell is detected in real - time by the battery - cell temperature sensor. According to the temperature of the second battery cell, the power of the gas - liquid pump is adjusted using the PID algorithm, so as to ensure the lowest energy consumption of the gas - liquid pump while gradually regulating the temperature of the second battery cell to the preset temperature. When the temperature of the second battery cell reaches the preset temperature, the gas - liquid pump is turned off, and the input of the third supercritical working fluid to the battery module is stopped.

[0020] Regulating the power of the gas - liquid pump in real - time according to the working condition can effectively save the energy consumption of the system.

[0021] Furthermore, after the input of the third supercritical working fluid is stopped, the third supercritical working fluid is drained from the battery module into the outlet channel and output to the return pipeline. The outlet channel is connected to the outlet position of the flow - splitting channel;

[0022] Meanwhile, the state of the third supercritical working fluid is monitored in the return pipeline. If the state of the third supercritical working fluid undergoes a cross - boundary phase change, the third supercritical working fluid is re - processed to the critical state through an electronic expansion valve and then the third supercritical working fluid returns to the working - fluid storage tank through the return pipeline.

[0023] By setting up the return pipeline, the supercritical working fluid can be recycled. The working fluid is prepared by the semiconductor system in the working - fluid storage tank, and after cooling and heat exchange, it returns to the working - fluid storage tank again, saving energy and reducing the complexity of the system. At the same time, the pressure sensor and temperature sensor in the return pipeline are used to monitor the state of the returning working fluid, and the electronic expansion valve is used to adjust the returning working fluid to keep the working fluid in the critical state, preparing for the next refrigeration pre - heating cycle.

[0024] Furthermore, the flow - splitting channel is a wing - type rib structure cold - hot dual channel, including: a cold - channel system and a hot - channel system;

[0025] The wing - type rib structure cold - hot dual channel contains an inlet position and an outlet position. Through the inlet position and the outlet position, the inlets and outlets of the cold - channel system and the hot - channel system are combined into one main channel;

[0026] The cold channel system is used for cell refrigeration and includes: a bottom heat spreader, cells, a top bracket, side cold plates, a front cold plate, interlayer cold plates, and a rear cold plate;

[0027] In the cold channel system, the top bracket is used to fix the cells within the side cold plates and the bottom heat spreader. The front cold plate and the rear cold plate are respectively provided with bottom slots to integrally fix the cells on the bottom heat spreader, and the interlayer cold plates are arranged at positions protruding the cell tabs;

[0028] The hot channel system is used for cell preheating and includes: a bottom heat spreader, cells, and a top bracket;

[0029] In the hot channel system, the bottom heat spreader is arranged at the bottom of the cells, and slots are provided around it so that the cells are fixed within the hot channel system through the fixing brackets and the slots.

[0030] Through the flow guiding function of the reversing solenoid valve, the cold and hot channels are fitted into a main channel, which saves costs and makes the system circuit more concise and efficient.

[0031] As a preferred embodiment, the cold channel system further includes:

[0032] Connect the pipes of the interlayer cold plates to the working pipeline, set a special-shaped four-way valve at the inlet, and at the same time set a number of branch pipelines according to the number of cell layers and install the branch pipelines between the cell layers; wherein, the interlayer cold plates include microchannels with wing-shaped ribs having arc-shaped openings and arc-shaped closings, and the wing-shaped rib structures are arranged in a staggered manner and are etched in the microchannels by chemical etching or atomic diffusion bonding etching;

[0033] Connect the inlet pipes of the front cold plate and the rear cold plate to the working pipeline, set them near the cell tabs, set a special-shaped three-way joint at the inlet, and at the same time divide a number of branch pipelines through trapezoidal notches between the inlet pipes; wherein, the branch pipelines are of wing-shaped rib structures, and each branch pipeline finally converges into the same outlet pipeline, and the outlet pipeline is connected to the return pipeline and is provided with a special-shaped four-way valve.

[0034] As a preferred embodiment, the hot channel system further includes:

[0035] Connect the inlet pipe of the bottom heat spreader to the working pipeline and divide the inlet pipe into a number of branch pipelines; wherein, the branch pipelines are of wing-shaped rib structures, and each branch pipeline finally converges into the same outlet pipeline, and the outlet pipeline is connected to the return pipeline.

[0036] Using an airfoil rib structure channel can reduce the fluid pressure drop, reduce the generation of secondary flow in the working medium flow, make the working medium flow faster and more uniform, and effectively improve the temperature uniformity of the battery module compared with the traditional serpentine channel, achieving a good heat exchange effect.

[0037] Another embodiment of the present invention correspondingly provides an energy power battery thermal management device, including: a start module, a working module, and a stop module;

[0038] The start module is used to monitor the temperature of the first battery cell of the power battery in real time. When the temperature of the first battery cell exceeds the preset working range, the first supercritical working medium in the accumulator is released and input into the working pipeline, and the semiconductor chip is started to process the working medium in the working medium storage tank into the second supercritical working medium; wherein, the first supercritical working medium is the supercritical working medium that entered the accumulator through the branch circuit in the working pipeline in the previous working cycle;

[0039] The working module is used to input the second supercritical working medium into the working pipeline. After the first supercritical working medium and the second supercritical working medium are input into the working pipeline, they enter the shunt channel successively, and the third supercritical working medium is output through the shunt channel and enters the battery module; wherein, after the second supercritical working medium is input into the working pipeline, it is shunted. The shunted second supercritical working medium flows into the shunt channel and the branch circuit respectively, and the second supercritical working medium passing through the branch circuit enters the accumulator;

[0040] The stop module is used to monitor the temperature of the second battery cell of the power battery after the third supercritical working medium enters the battery module. When the temperature of the second battery cell returns to the preset working range, the input of the third supercritical working medium is stopped.

[0041] Compared with the prior art, a power battery thermal management device disclosed in an embodiment of the present invention stores the working medium, laying a foundation for further temperature regulation of the power battery by the supercritical working medium in the subsequent working medium storage tank, and improving the working efficiency of the thermal management system.

[0042] Another embodiment of the present invention provides an energy power battery thermal management system, including a controller, battery cells, a working medium storage tank, a plurality of accumulators, a plurality of pressure sensors, a plurality of temperature sensors, a gas-liquid pump, an airfoil rib structure cold and hot dual-channel, and a plurality of pipelines. The controller is used to implement an energy power battery thermal management method described in the above-mentioned embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is a schematic flow chart of an energy power battery thermal management method provided by an embodiment of the present invention.

[0044] Figure 2 is a schematic structural diagram of a supercritical fluid power cycle system provided by an embodiment of the present invention.

[0045] Figure 3 It is a schematic structural diagram of a hot and cold dual-channel system of an airfoil rib structure provided by an embodiment of the present invention.

[0046] Figure 4 It is a schematic structural diagram of an interlayer equalizing plate in a hot and cold dual-channel system of an airfoil rib structure provided by an embodiment of the present invention.

[0047] Figure 5 It is a schematic structural diagram of front and rear equalizing plates in a hot and cold dual-channel system of an airfoil rib structure provided by an embodiment of the present invention.

[0048] Figure 6 It is a schematic structural diagram of a bottom heat equalizing plate in a hot and cold dual-channel system of an airfoil rib structure provided by an embodiment of the present invention.

[0049] Figure 7 It is a schematic structural diagram of a thermal management device for an energy power battery provided by an embodiment of the present invention. Specific embodiments

[0050] Supercritical working fluids have both the low viscosity and high diffusivity properties of gases and good heat conduction characteristics. Their density is relatively high and close to that of liquids, accompanied by good solubility and transport characteristics. It is easier to achieve a reduction in compression work consumption, which helps to relieve the tight storage volume and further improve the compactness and convenience of system components. Supercritical working fluids have extremely high power density and a simple cycle, and also show significant superiority during the operation of the entire system. When both the pressure and temperature exceed the critical point of the working fluid, the working fluid becomes a non-condensable gas that does not liquefy due to pressure changes. Common supercritical working fluids include supercritical methane, supercritical CO2, etc. The embodiment of the present invention provides a thermal management method for an energy power battery based on supercritical working fluids.

[0051] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0052] See Figure 1 , which is a schematic flow diagram of a thermal management method for an energy power battery provided by an embodiment of the present invention, including:

[0053] S101: Monitor the temperature of the first battery cell of the power battery in real time. When the temperature of the first battery cell exceeds the preset working range, release the first supercritical working fluid in the accumulator into the working pipeline, and start the semiconductor chip to process the working fluid in the working fluid storage tank into the second supercritical working fluid; wherein, the first supercritical working fluid is the supercritical working fluid that entered the accumulator through the branch circuit in the working pipeline in the previous working cycle;

[0054] S102: Input the second supercritical working fluid into the working pipeline. After the first supercritical working fluid and the second supercritical working fluid enter the working pipeline, they enter the shunt channel successively, and the third supercritical working fluid is output through the shunt channel and enters the battery module; wherein, after the second supercritical working fluid is input into the working pipeline, it is shunted. The shunted second supercritical working fluid flows into the shunt channel and the branch circuit respectively, and the second supercritical working fluid passing through the branch circuit enters the accumulator;

[0055] S103: After the third supercritical working fluid enters the battery module, monitor the temperature of the second battery cell of the power battery. When the temperature of the second battery cell returns to the preset working range, stop the input of the third supercritical working fluid.

[0056] A thermal management method for an energy power battery provided by an embodiment of the present invention stores the supercritical working fluid in the accumulator first. When the battery needs to be cooled or preheated, the stored working fluid is released first, laying the foundation for the subsequent supercritical working fluid in the working fluid storage tank to further adjust the temperature of the power battery, and improving the working efficiency of the thermal management system.

[0057] For step S101, specifically, the real-time monitoring of the temperature of the battery cell of the power battery, when the temperature of the first battery cell exceeds the preset working range, releasing the first supercritical working fluid in the accumulator into the working pipeline specifically includes:

[0058] Obtain the first temperature at the positive electrode tab on the surface of the battery cell of the power battery, and at the same time obtain the second temperature at the bottom of the battery cell in the same cross section;

[0059] Record the first temperature and the second temperature, and at the same time calculate the difference between the two. When one of the first temperature and the second temperature exceeds the preset temperature threshold or the difference exceeds the preset temperature difference threshold, release the first supercritical working fluid in the accumulator into the working pipeline.

[0060] In a preferred embodiment, see Figure 2, a temperature sensor T3 is arranged at the positive electrode tab on the surface of the battery cell, and a temperature sensor T4 is arranged at the bottom of the battery cell with the same cross-section on the surface of the battery cell to monitor the highest temperature and temperature difference of the battery cell. When the highest temperature on the surface of the battery cell exceeds 40 °C or the temperature difference ΔT (ΔT = T3 - T4) exceeds 6 °C, the cold working condition is started; when the temperature on the surface of the battery cell is lower than 20 °C, the hot working condition is started. At this time, the gas-liquid power pump is in a pre-start state, and the semiconductor in the working medium storage tank starts the refrigeration or heating function.

[0061] Meanwhile, the solenoid valve in the accumulator switches from the normally closed state to the normally open state, and the supercritical working medium in the accumulator is first output from the accumulator to the pipeline and input into the battery module through the P-A gear of the solenoid valve III. Among them, when the accumulator storage tank is prepared, the wall spacer layer is evacuated and nano-thermal insulation material is added to ensure that the critical working medium does not change in pressure and temperature in the storage tank. The purpose of setting the accumulator is to play a pre-cooling role when the working condition is started. The refrigeration of the semiconductor in the working medium storage tank releases the refrigeration working medium first to quickly cool down the battery module, effectively saving the system operation time.

[0062] For S102, specifically, the inputting the second supercritical working medium into the working pipeline, after the first supercritical working medium and the second supercritical working medium are input into the working pipeline, they pass through the shunt channel successively, and the third supercritical working medium is output through the shunt channel and enters the battery module, specifically including:

[0063] Monitoring the state of the second supercritical working medium by using the working medium pressure sensor and the working medium temperature sensor in the working medium storage tank. When it is monitored that the second supercritical working medium reaches the working state, start the gas-liquid pump and input the second supercritical working medium into the working pipeline;

[0064] After the first supercritical working medium and the second supercritical working medium are input into the working pipeline, they enter the shunt channel successively through the inlet gear of the shunt channel; among them, the shunt channel is connected to several pipelines in the battery module;

[0065] After the first supercritical working medium and the second supercritical working medium enter the shunt channel, the third supercritical working medium is output through the shunt channel, and the third supercritical working medium enters several pipelines in the battery module respectively; among them, part of the second supercritical working medium enters the branch circuit after being input into the working pipeline, and the branch circuit is connected to the accumulator. When the part of the second supercritical working medium enters the accumulator, it becomes the first supercritical working medium; when the accumulator pressure sensor in the accumulator monitors that the accumulator is full of the working medium, stop inputting the supercritical working medium from the branch circuit into the accumulator.

[0066] In a preferred embodiment, refer to Figure 2When the pressure sensor and temperature sensor in the working fluid storage tank monitor that the supercritical working fluid in the tank has reached the ideal working state, the gas-liquid power pump is started to output the supercritical working fluid in the working fluid storage tank. Driven by the gas-liquid power pump, the supercritical working fluid in the accumulator and most of the supercritical working fluid in the working fluid storage tank enter the reversing solenoid valve III along the working pipeline, and output the supercritical working fluid from the four inlets a, d, g, and f through the shunt channel to enter the battery module. Another part of the supercritical working fluid in the working fluid storage tank enters the accumulator through the branch circuit. After the pressure sensor in the accumulator monitors that the accumulator is full of working fluid, the accumulator solenoid valve turns to the normally off state and stops storing supercritical working fluid.

[0067] By setting up a diversion channel, the supercritical working fluid can enter the battery module evenly for work, and the branch circuit is designed to allow part of the supercritical working fluid in the storage tank to be replenished into the accumulator, which saves energy while paving the way for the next working condition startup.

[0068] For step S103, specifically, after the third supercritical working fluid enters the battery module, monitoring the temperature of the second battery cell of the power battery, and stopping the input of the third supercritical working fluid when the temperature of the second battery cell returns to the preset working range, specifically includes:

[0069] After the third supercritical working fluid enters several pipes of the battery module, the temperature of the second battery cell is detected in real time by the battery cell temperature sensor, and the power of the gas-liquid pump is adjusted by the PID algorithm according to the temperature of the second battery cell, so that the energy consumption of the gas-liquid pump is minimized while the temperature of the second battery cell is gradually controlled to a preset temperature; when the temperature of the second battery cell reaches the preset temperature, the gas-liquid pump is turned off and the input of the third supercritical working fluid to the battery module is stopped.

[0070] In a preferred embodiment, see Figure 2 The temperature sensor on the surface of the battery cell monitors the cooling or preheating condition of the battery cell in real time. The power of the gas-liquid power pump is adjusted in real time according to the working condition through the PID algorithm, ensuring the best working efficiency while saving energy as much as possible. When the temperature of the battery cell reaches the preset temperature, the gas-liquid power pump is turned off and the input of supercritical working fluid to the battery module is stopped.

[0071] Real-time regulation of the gas-liquid pump power according to the working conditions can effectively save system energy consumption.

[0072] Furthermore, an energy power battery thermal management method provided by an embodiment of the present invention also includes:

[0073] When the input of the third supercritical working fluid stops, the third supercritical working fluid is collected from the battery module into the outlet channel and output to the reflux pipeline, and the outlet channel is connected to the outlet position of the shunt channel;

[0074] Meanwhile, monitor the state of the third supercritical working fluid in the reflux pipeline. If the state of the third supercritical working fluid undergoes a cross-boundary phase change, the third supercritical working fluid is reprocessed to the critical state through an electronic expansion valve and then returned to the working fluid storage tank through the reflux pipeline.

[0075] In a preferred embodiment, refer to Figure 2 , after the supercritical working fluid enters the battery module and completes cooling / preheating, it converges into the outlet channel from the battery module and flows to the reflux pipeline through the B-T gear of the reversing solenoid valve III. A pressure sensor II, a temperature sensor II, and an electronic expansion valve are provided in the reflux management. The temperature and pressure of the supercritical working fluid in the reflux pipeline are detected by the pressure sensor II and the temperature sensor II. If it is monitored that the supercritical working fluid undergoes a cross-boundary phase change, the working fluid is re-regulated to the supercritical state by using the electronic expansion valve and then input back into the working fluid storage tank.

[0076] By setting up the reflux pipeline, the supercritical working fluid can be recycled. The working fluid is prepared by the semiconductor system in the working fluid storage tank, and after cooling and heat exchange, it returns to the working fluid storage tank again, saving energy and reducing the complexity of the system. At the same time, the pressure sensor and temperature sensor in the reflux pipeline are used to monitor the state of the reflux working fluid, and the reflux working fluid is adjusted by the electronic expansion valve to keep the working fluid in the critical state, preparing for the next refrigeration and preheating cycle.

[0077] Refer to Figure 3 , which is a schematic structural diagram of an airfoil rib structure cold and hot dual-channel system provided by an embodiment of the present invention, including: a cold channel system and a hot channel system;

[0078] The airfoil rib structure cold and hot dual-channel in the present invention is used as a diversion channel, including an inlet gear and an outlet gear. Through the inlet gear and the outlet gear, the inlets and outlets of the cold channel system and the hot channel system are combined into a main channel;

[0079] The cold channel system is used for cell refrigeration, including: a bottom heat sink 1, a cell 2, a top bracket 9, a side cold plate, a front cold plate 3, an interlayer cold plate 8, and a rear cold plate 10;

[0080] In the cold channel system, the top bracket 9 is used to fix the cell 2 inside the side cold plate and the bottom heat sink. The front cold plate 3 and the rear cold plate 10 are respectively provided with bottom slots to fix the whole cell on the bottom heat sink 1, and the interlayer cold plate 8 is arranged at the tab protruding from the cell 2;

[0081] The hot channel system is used for cell preheating, including: a bottom heat sink 1, a cell 2, and a top bracket 9;

[0082] In the hot channel system, the bottom heat spreader 1 is disposed at the bottom of the battery cell 2, and clamping grooves are provided around it, so that the battery cell is fixed in the hot channel system through the top bracket 9 and the clamping grooves.

[0083] Furthermore, the cold channel system further includes:

[0084] Connect the pipes of the interlayer cold plate 8 to the working pipeline, and set a special-shaped four-way valve at the inlet. At the same time, according to the number of battery cell layers, a plurality of branch pipelines are provided, and the plurality of branch pipelines are installed between the battery cell layers; wherein, the interlayer cold plate includes micro-channels with a wing-shaped rib structure with an arc-shaped opening and an arc-shaped closing, and the wing-shaped rib structures are arranged in a staggered manner and are etched in the micro-channels by chemical etching method or atomic diffusion bonding etching.

[0085] Connect the inlet pipes of the front cold plate 3 and the rear cold plate 10 to the working pipeline, and dispose them near the tabs of the battery cell 2. Set a special-shaped three-way joint at the inlet. At the same time, a plurality of branch pipelines are separated through trapezoidal notches between the inlet pipes; wherein, the plurality of branch pipelines are of a wing-shaped rib structure, and each branch pipeline finally converges into the same outlet pipeline, and the outlet pipeline is connected to the return pipeline, and a special-shaped four-way valve is provided.

[0086] Furthermore, the hot channel system further includes:

[0087] Connect the inlet pipe of the bottom heat spreader 1 to the working pipeline, and divide the inlet pipe into a plurality of branch pipelines; wherein, the plurality of branch pipelines are of a wing-shaped rib structure, and each branch pipeline finally converges into the same outlet pipeline, and the outlet pipeline is connected to the return pipeline.

[0088] In a preferred embodiment, a heat-conducting adhesive is evenly applied between the battery cell 2 and the cold plate, which can form a protective film on the surface of the battery cell 2 to prevent the leakage of the refrigeration working medium from causing a thermal runaway problem and improve the safety of the system operation. The front cold plate 3 and the rear cold plate 10 of the battery module are respectively provided with bottom clamping grooves to integrally fix the battery cell 2 on the bottom heat spreader 1, which can prevent the battery cell 2 from colliding due to shaking. The material of the cold plate is aluminum plate, and the thickness is about 2 mm. In addition, since the tabs are connected with heat-conducting metal sheets, the highest temperature on the surface of the battery cell 2 is generally near the tabs. Therefore, setting the main inlet pipelines of the cold plate at the positions protruding the tabs of the battery cell 2 can achieve the best cooling effect at the highest temperature position of the battery cell 2, effectively improve the surface temperature uniformity of the battery cell 2, and prevent the inlet main pipe from being clamped between the battery cell layers and leaking to corrode and damage the surface of the battery cell 2.

[0089] The structure of the interlayer cold plate 8 is as Figure 4As shown, the total flow path inlet d is arranged at the upper edge of the tab of the battery cell 2. According to the number of layers of the battery cell 2, the sub-inlets d1, d2, d3... are set. The sub-inlets uniformly flow into the space between the layers of the battery cell 2 from the total inlet d of the special-shaped four-way valve arranged in the center. A trapezoidal groove inlet is arranged in the upper pipeline, which increases the flow velocity of the supercritical working fluid while reducing the pressure drop flow resistance.

[0090] A microchannel with an airfoil rib structure with an arc-shaped opening and an arc-shaped closing is arranged between the cold plates and is etched in the microchannel by chemical etching or atomic diffusion bonding. The airfoil rib structure can separate the supercritical working fluids that are squeezing each other and make them quickly converge towards the mid-arc line, forming a jet flow towards the rib. This can not only increase the turbulence degree of the fluid working medium, but also improve the synergy of the temperature and velocity fields, and enhance the heat transfer by thinning the heat transfer boundary layer at the tail.

[0091] The airfoil rib structure used in the present invention adopts a staggered arrangement. Compared with the parallel and juxtaposed airfoil rib structure, the staggered airfoil ribs have a greater advantage in reducing the flow resistance of the airfoil fins by alternately presenting sudden increases or sudden contractions in the cross-section, enhancing the heat transfer effect while reducing the pumping loss of the power pump. At the same time, the staggered airfoil structure makes the local heat transfer performance of the supercritical working fluid gradually decrease along the flow direction while the local flow resistance remains basically unchanged. It is measured by experiments that the pressure drop is reduced by 40% when the completely staggered arrangement and the incompletely staggered arrangement obtain the same heat transfer effect.

[0092] Both the beginning and the end of the airfoil rib microchannel of the present invention adopt an arc shape. Reducing the heat exchange pipe diameter at the beginning and the end of the airfoil microchannel is beneficial to increasing the Reynolds number of the supercritical working fluid, thereby achieving the purpose of enhancing heat transfer. After the supercritical working fluid flows into the cold plate with the airfoil rib structure microchannel, its flow velocity distribution becomes more uniform, and the secondary disturbance is also eliminated, and good heat transfer performance can be maintained. Under a fixed heat load, using a thin airfoil rib structure with a thickness of 2 mm can obtain a lower pressure drop and a higher cycle efficiency in the heat exchange cycle.

[0093] After the supercritical working fluid completes the refrigeration heat exchange through the airfoil rib microchannel, it flows out from the bottom through the h1 pipeline. It flows out through the h1 pipeline and converges into the h outlet pipeline equipped with a special-shaped four-way valve through the h1, h2, h3... sub-pipelines, and then flows out of the battery module to complete the refrigeration heat exchange of the battery cell.

[0094] The structures of the front and rear cold plates are as Figure 5As shown, the supercritical working fluid enters from the a inlet arranged near the pole ear of the battery cell 2 through the special-shaped three-way joint, enters the a1, a2, a3... branch pipelines through the trapezoidal notch between the pipes, and flows into the channel along the wing-shaped rib structure. Compared with the traditional serpentine liquid cooling pipeline, the wing-shaped rib pipeline channel can not only effectively reduce the fluid pressure drop, but also make the working fluid flow evenly and reduce secondary flow disturbance. The design from the top to the bottom of the battery cell 2 can maintain the temperature uniformity of the battery cell 2 and avoid the problem of large difference between the inlet temperature and the outlet temperature when using the wall serpentine pipeline. The wing-shaped fins etched on the thin plate play a good role in guiding flow, while increasing the heat exchange area and strengthening cooling and heat exchange. The front and rear side heat spreaders are provided with convex grooves at the top return pipe, which together with the grooves of the bottom heat spreader 1 form a slot, which can cooperate with the top bracket 9 to fix the battery module well, and prevent the wall coolant from leaking due to the impact caused by the shaking of the battery cell during vehicle operation. The supercritical working fluid flowing to the front cooling plate 3 enters from the microchannel a1, a2, a3... inlets, flows out from the c1, c2, c3... outlets, and enters the main circuit after being converged to the c outlet. The supercritical working fluid flowing to the rear cooling plate 10 flows in from the g1, g2, g3... branch inlets, flows out from the e1, e2, e3... branch outlets, and enters the main circuit after being converged to the e outlet, and the cycle is completed through uniform cooling and heat exchange between the microchannels of the cooling plate.

[0095] The structure of the bottom heat plate 1 is as follows Figure 6 As shown, the preheated supercritical working fluid flows into the battery module from the inlet f of the bottom heat spreader 1 driven by the gas-liquid pump, and is branched to the branch inlets f1, f2, f3... through the wing-shaped rib structure microchannel, and finally flows to the branch outlets b1, b2, b3... The branch outlets merge into the loop total outlet b from the center and then flow out of the bottom heat spreader 1 to complete the preheating cycle.

[0096] It has been tested that the cooling time is about five times longer than the heating time when the same temperature is changed at the same power. Therefore, the cooling plate is arranged at the front and rear positions of the sides and the layer intervals where the contact area with the battery surface is the largest to increase the heat exchange area, and the heat spreader is arranged at the bottom of the battery cell where the temperature rises the slowest. The bottom heat spreader 1 surface is processed around to prepare a base slot that can fix the battery cell, so that the battery cell 2 can be fixed in the thermal management system through the top bracket 9 and the bottom heat spreader 1 slot to prevent the battery cell 2 from shaking and detaching due to bumps.

[0097] The design of a multi - micro - passage airfoil rib structure inside the bottom heat pipe 1 enables efficient heat exchange between the bottom of the battery cell and the supercritical working fluid in the micro - channels, achieving a faster pre - heating effect in low - temperature environments. At the same time, the design of multiple micro - channels enables the supercritical working fluid to flow through the bottom heat pipe 1 for a longer time, and the airfoil rib structure with an arc - shaped head can play a good role in diverting the supercritical working fluid, forming a jet flow towards the rib at the tail of the airfoil rib, effectively reducing the occurrence of secondary disturbance of the fluid working medium, making the working fluid flow more evenly through the micro - channels and reducing the pressure drop. The multi - channel micro - flow path design with an airfoil rib structure can not only effectively enhance the heat exchange effect between the supercritical working fluid and the battery module, enabling rapid pre - heating of the power battery in low - temperature environments, but also achieve the inflow and pre - heating of the working fluid faster than the traditional serpentine liquid path structure design under the same power. Since the airfoil rib structure channels can make the pre - heating more balanced, with a smaller pressure drop and a larger heat exchange area, they can effectively improve the problem of uneven pre - heating at the inlet and outlet of the traditional serpentine pipeline and strengthen the heat exchange effect.

[0098] See Figure 7 , which is an energy power battery thermal management device provided by an embodiment of the present invention, includes: a start module 201, a working module 202, and a stop module 203;

[0099] The start module 201 is used to monitor the temperature of the first battery cell of the power battery in real - time. When the temperature of the first battery cell exceeds the preset working range, it releases the first supercritical working fluid in the accumulator into the working pipeline and starts the semiconductor chip to process the working fluid in the working fluid storage tank into the second supercritical working fluid; wherein, the first supercritical working fluid is the supercritical working fluid that entered the accumulator through the branch circuit in the working pipeline during the previous working cycle;

[0100] The working module 202 is used to input the second supercritical working fluid into the working pipeline. After the first supercritical working fluid and the second supercritical working fluid are input into the working pipeline, they enter the shunt channel successively, and the third supercritical working fluid is output through the shunt channel and enters the battery module; wherein, after the second supercritical working fluid is input into the working pipeline, it is shunted. The shunted second supercritical working fluid flows into the shunt channel and the branch circuit respectively, and the second supercritical working fluid passing through the branch circuit enters the accumulator;

[0101] The stop module 203 is used to monitor the temperature of the second battery cell of the power battery after the third supercritical working fluid enters the battery module. When the temperature of the second battery cell returns to the preset working range, it stops the input of the third supercritical working fluid.

[0102] An energy power battery thermal management device provided by an embodiment of the present invention stores the working fluid, laying a foundation for further temperature regulation of the power battery by the supercritical working fluid in the subsequent working fluid storage tank, and improving the working efficiency of the thermal management system.

[0103] Another embodiment of the present invention provides an energy power battery thermal management system, which includes a controller, battery cells, a working medium storage tank, a plurality of energy accumulators, a plurality of pressure sensors, a plurality of temperature sensors, a gas-liquid pump, a double-channel heat exchanger with airfoil rib structure, and a plurality of pipelines. The controller is used to implement the energy power battery thermal management method described in the above-mentioned embodiment of the present invention.

[0104] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. In addition, in the attached drawings of the device embodiments provided by the present invention, the connection relationship between the modules indicates that they have a communication connection, which can be specifically implemented as one or more communication buses or signal lines. Those of ordinary skill in the art can understand and implement it without creative work.

[0105] The above is the preferred embodiment of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. A thermal management method for an energy power battery, characterized in that, Including: Real-time monitor the temperature of the first battery cell of the power battery. When the temperature of the first battery cell exceeds the preset working range, release the first supercritical working fluid in the accumulator and input it into the working pipeline, and start the semiconductor sheet to process the working fluid in the working fluid storage tank into the second supercritical working fluid; wherein, the first supercritical working fluid is the supercritical working fluid that entered the accumulator through the branch circuit in the working pipeline during the previous working cycle. Input the second supercritical working fluid into the working pipeline. After the first supercritical working fluid and the second supercritical working fluid are input into the working pipeline, they enter the shunt channel successively, and output the third supercritical working fluid through the shunt channel and enter the battery module; wherein, after the second supercritical working fluid is input into the working pipeline, it is shunted. The shunted second supercritical working fluid flows into the shunt channel and the branch circuit respectively, and the second supercritical working fluid passing through the branch circuit enters the accumulator. After the third supercritical working fluid enters the battery module, monitor the temperature of the second battery cell of the power battery. When the temperature of the second battery cell returns to the preset working range, stop the input of the third supercritical working fluid. After the input of the third supercritical working fluid stops, collect the third supercritical working fluid from the battery module into the outlet channel and output it to the return pipeline. The outlet channel is connected to the outlet position of the shunt channel; meanwhile, monitor the state of the third supercritical working fluid in the return pipeline. If the state of the third supercritical working fluid undergoes a cross-boundary phase change, reprocess the third supercritical working fluid to the critical state through an electronic expansion valve and then make the third supercritical working fluid return to the working fluid storage tank through the return pipeline.

2. The thermal management method of an energy power battery according to claim 1, characterized in that The real-time monitoring of the temperature of the battery cell of the power battery. When the temperature of the first battery cell exceeds the preset working range, releasing the first supercritical working fluid in the accumulator and inputting it into the working pipeline specifically includes: Obtain the first temperature at the positive electrode tab on the surface of the battery cell of the power battery, and at the same time obtain the second temperature at the bottom of the battery cell in the same cross-section. Record the first temperature and the second temperature, and at the same time calculate the difference between the two. When one of the first temperature and the second temperature exceeds the preset temperature threshold or the difference exceeds the preset temperature difference threshold, release the first supercritical working fluid in the accumulator and input it into the working pipeline.

3. The thermal management method of an energy power battery according to claim 1, characterized in that, Input the second supercritical working fluid into the working pipeline. After the first supercritical working fluid and the second supercritical working fluid are input into the working pipeline, they successively pass through the shunt channel, and output the third supercritical working fluid through the shunt channel and enter the battery module, specifically including: Use the working fluid pressure sensor and the working fluid temperature sensor in the working fluid storage tank to monitor the state of the second supercritical working fluid. When it is monitored that the second supercritical working fluid reaches the working state, start the gas-liquid pump and input the second supercritical working fluid into the working pipeline. After the first supercritical working fluid and the second supercritical working fluid are input into the working pipeline, they enter the shunt channel successively through the inlet position of the shunt channel; wherein, the shunt channel is connected to several pipelines in the battery module. After the first supercritical working fluid and the second supercritical working fluid enter the diversion channel, a third supercritical working fluid is output through the diversion channel, and the third supercritical working fluid enters several pipelines in the battery module respectively; wherein, a part of the second supercritical working fluid is input into the working pipeline and then enters the branch circuit, and the branch circuit is connected to the accumulator. When the part of the second supercritical working fluid enters the accumulator, it becomes the first supercritical working fluid; when the accumulator pressure sensor in the accumulator monitors that the accumulator is full of the working fluid, the input of the supercritical working fluid from the branch circuit to the accumulator is stopped.

4. The thermal management method of an energy power battery according to claim 1, wherein, After the third supercritical working fluid enters the battery module, the second cell temperature of the power battery is monitored. When the second cell temperature returns to the preset working range, the input of the third supercritical working fluid is stopped, specifically including: After the third supercritical working fluid enters several pipelines of the battery module, the second cell temperature is detected in real time by the cell temperature sensor. According to the second cell temperature, the power of the gas-liquid pump is adjusted by using the PID algorithm, so as to ensure the lowest energy consumption of the gas-liquid pump while the second cell temperature is gradually regulated to the preset temperature; when the second cell temperature reaches the preset temperature, the gas-liquid pump is turned off, and the input of the third supercritical working fluid to the battery module is stopped.

5. The thermal management method for an energy power battery according to claim 1, characterized in that, The diversion channel is a wing-shaped rib structure cold and hot double channel, including: a cold channel system and a hot channel system; The wing-shaped rib structure cold and hot double channel includes an inlet gear and an outlet gear. Through the inlet gear and the outlet gear, the inlets and outlets of the cold channel system and the hot channel system are combined into a main channel; The cold channel system is used for cell refrigeration, including: a bottom heat sink plate, a cell, a top bracket, a side cold plate, a front cold plate, an interlayer cold plate, and a rear cold plate; In the cold channel system, the top bracket is used to fix the cell in the side cold plate and the bottom heat sink plate. The front cold plate and the rear cold plate are respectively provided with bottom card slots so that the whole cell is fixed on the bottom heat sink plate, and the interlayer cold plate is arranged at the position protruding the cell tab; The hot channel system is used for cell preheating, including: a bottom heat sink plate, a cell, and a top bracket; In the hot channel system, the bottom heat sink plate is arranged at the bottom of the cell, and card slots are arranged around it, so that the cell is fixed in the hot channel system through the top bracket and the card slots.

6. The thermal management method of an energy power battery according to claim 5, wherein, The cold channel system also includes: Connect the pipeline of the interlayer cold plate to the working pipeline, set a special-shaped four-way valve at the inlet, and at the same time set several branch pipelines according to the number of cell layers, and install the several branch pipelines between the cell layers; wherein, the interlayer cold plate includes a microchannel with a wing-shaped rib structure of an arc-shaped opening and an arc-shaped closing. The wing-shaped rib structure is arranged in a staggered arrangement and is etched in the microchannel by chemical etching method or atomic diffusion bonding etching. Connect the inlet pipes of the front and rear soaking plates to the working pipeline, set them near the tabs of the battery cells, and install special-shaped three-way joints at the inlets. At the same time, divide several branch pipelines through trapezoidal notches between the inlet pipes; among them, the several branch pipelines are in the shape of wing ribs, and each branch pipeline finally converges into the same outlet pipeline, and the outlet pipeline is connected to the return pipeline and is provided with a special-shaped four-way valve.

7. The thermal management method for an energy power battery according to claim 5, characterized in that, The thermal channel system further includes: Connect the inlet pipe of the bottom soaking plate to the working pipeline, and divide the inlet pipe into several branch pipelines; among them, the several branch pipelines are in the shape of wing ribs, and each branch pipeline finally converges into the same outlet pipeline, and the outlet pipeline is connected to the return pipeline.

8. A thermal management device for an energy power battery, characterized in that, It includes: A start module, a working module, and a stop module; The start module is used to monitor the temperature of the first battery cell of the power battery in real time. When the temperature of the first battery cell exceeds the preset working range, release the first supercritical working fluid in the accumulator and input it into the working pipeline, and start the semiconductor chip to process the working fluid in the working fluid storage tank into a second supercritical working fluid; among them, the first supercritical working fluid is the supercritical working fluid that entered the accumulator through the branch circuit in the working pipeline during the previous working cycle. The working module is used to input the second supercritical working fluid into the working pipeline. After the first supercritical working fluid and the second supercritical working fluid are input into the working pipeline, they enter the shunt channel successively, and output a third supercritical working fluid through the shunt channel and enter the battery module; among them, after the second supercritical working fluid is input into the working pipeline, it is shunted, and the shunted second supercritical working fluid flows into the shunt channel and the branch circuit respectively, and the second supercritical working fluid passing through the branch circuit enters the accumulator. The stop module is used to monitor the temperature of the second battery cell of the power battery after the third supercritical working fluid enters the battery module. When the temperature of the second battery cell returns to the preset working range, stop the input of the third supercritical working fluid. After the input of the third supercritical working fluid stops, the third supercritical working fluid is converged from the battery module into the outlet channel and output to the return pipeline, and the outlet channel is connected to the outlet gear of the shunt channel; at the same time, monitor the state of the third supercritical working fluid in the return pipeline. If the state of the third supercritical working fluid undergoes a cross-boundary phase change, the third supercritical working fluid is reprocessed to the critical state through an electronic expansion valve and then the third supercritical working fluid returns to the working fluid storage tank through the return pipeline.

9. An energy power battery thermal management system, characterized in that, It includes a controller, battery cells, a working fluid storage tank, several accumulators, several pressure sensors, several temperature sensors, a gas-liquid pump, a wing-rib structure cold and hot dual channel, and several pipelines. The controller is used to execute a thermal management method for an energy power battery according to any one of claims 1 to 7.

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