Multi-dimensional heat management and safety protection system for battery changing cabinet of electric bicycle

Abstract

The invention discloses a multi-dimensional heat management and safety protection system for an electric bicycle battery replacement cabinet, and belongs to the technical field of heat management of electric bicycle heat exchange stations. According to the system, through a multi-dimensional thermal management framework of a phase change material plate, a liquid cooling plate and a wide-temperature-range heat pump, temperature, pressure and smoke multi-sensor monitoring and layered regulation and control of a thermal management subsystem are combined, so that accurate control over the temperature in a battery bin and early warning of battery thermal runaway are achieved; meanwhile, the safety of battery replacement operation is guaranteed by means of a linkage control mechanism of a front bin door and a rear bin door, a catapulting device composed of a compressed carbon dioxide gas storage tank, an electromagnetic valve, an I-shaped pushing rod and an air cylinder is matched, a fault battery can be rapidly pushed into a fire-fighting bin when a thermal runaway signal is detected, a full-link safety protection system is formed from early warning, temperature control to emergency disposal, and the safety of the battery replacement operation is guaranteed. The problems that an existing battery replacement cabinet is uneven in battery heat dissipation, lagged in thermal runaway response and single in safety protection are effectively solved, and the operation safety and reliability of the electric bicycle battery replacement cabinet are remarkably improved.

Description

Technical Field

[0001] This invention relates to a multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets, which belongs to the technical field of thermal management for electric bicycle heat exchange stations. Background Technology

[0002] Currently, the thermal management technology of most electric bicycle battery swapping cabinets (especially small and medium-sized stations) is still in its early stages, adopting simple ventilation and basic temperature control modes, lacking a systematic and intelligent thermal management solution. Specifically, the following technical defects exist: First, the heat dissipation method is inefficient and singular. More than 70% of small and medium-sized battery swapping cabinets rely solely on natural ventilation and heat dissipation through axial flow fans and louvers. During the high temperatures of summer, the heat dissipation efficiency is less than 30%, which cannot effectively remove heat from the cabinet. Some stations equipped with small air conditioners adopt a uniform cooling mode for the entire cabinet, without zoned temperature control based on the heat load differences between the battery charging area and the storage area. This results in excessively high temperatures in the charging area and excessively low temperatures in the storage area, which not only wastes energy but also fails to meet the temperature control requirements of different areas. Secondly, there is a lack of early warning and protection against thermal runaway. Most existing battery swapping cabinets are only equipped with basic early warning devices such as temperature sensors and smoke detectors. The temperature sensor density is low (only one sensor for every 10 batteries), making it difficult to monitor the temperature changes of individual batteries in real time. Furthermore, there is a lack of thermal runaway suppression measures. Once a battery experiences thermal runaway, the only recourse is to trigger a fire extinguishing device (such as a dry powder extinguisher) via the smoke detector. However, dry powder can damage surrounding batteries and equipment, failing to prevent the chain reaction of thermal runaway. In several battery swapping cabinet fires in 2024, the fire spread to more than 10 batteries within 3 minutes of ignition from a single battery. Thirdly, battery thermal management is disconnected from the battery swapping process. The thermal management system of the swapping cabinet is not linked to the battery turnover process. For example, high-temperature batteries that have just finished discharging are directly connected to the charging system without pre-cooling; low-temperature batteries that have finished charging are directly stored in the low-temperature storage chamber without insulation. This leads to decreased battery charging and discharging efficiency and prolonged exposure to fluctuating temperature environments, shortening battery cycle life. Summary of the Invention

[0003] To address the problems existing in the prior art, this invention provides a multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets, which provides multi-dimensional thermal management and safety protection for batteries.

[0004] The technical solution adopted in this invention is: a multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets, which includes a cabinet, a fire compartment and an axial flow fan. The cabinet includes a battery area and an ejection area above the fire compartment.

[0005] The battery area is divided into several battery compartments, each with a front door and a rear door. The side walls of each battery compartment are made of phase change material, and the bottom of each compartment has a liquid-cooled plate with a temperature sensor installed. Each battery compartment contains a single battery cell, and the compartment above it contains a pressure sensor and a smoke sensor. At the linkage control node between the front and rear doors, a front and rear door linkage control module is configured. Its linkage control logic is as follows: when the front door is open, the front and rear door linkage control module keeps the rear door locked and cannot be opened; when the front door is locked and closed, the front and rear door linkage control module releases the locking restriction on the rear door, making it openable.

[0006] An ejection device is installed between the front compartment door and the individual battery. The ejection device includes a compressed carbon dioxide storage tank, an ejection solenoid valve, a push rod, and a cylinder. A cavity is provided between the compressed carbon dioxide storage tank and the first end face of the I-shaped push rod. The ejection solenoid valve is installed at the opening of the compressed carbon dioxide storage tank. One end of the cylinder is fixed to the front compartment door, and the other end acts on the second end face of the push rod. After the ejection device is triggered, the individual battery is pushed into the fire compartment through the rear compartment door.

[0007] The system is also equipped with a wide-temperature-range heat pump on the outside of the cabinet. The wide-temperature-range heat pump is connected to the liquid cooling plate through pipelines to deliver the temperature-controlled working fluid to the liquid cooling plate.

[0008] The system also includes a thermal management subsystem, which comprises a battery thermal runaway early warning module, a battery thermal runaway control module, a battery compartment thermal management module, and an end-point temperature control module.

[0009] Furthermore, the operation process of the ejection device is as follows:

[0010] Initial state: The compressed carbon dioxide storage tank is pre-filled with high-pressure carbon dioxide gas at a preset pressure; the solenoid valve is in the normally closed state and is sealed between the compressed carbon dioxide storage tank and the cavity, allowing the high-pressure gas in the compressed carbon dioxide storage tank to flow to the push rod side and the cylinder side; the I-shaped push rod is in the initial reset position, and the cylinder is kept at normal pressure.

[0011] Triggering phase: When the system receives a preset system-triggered thermal runaway signal, the ejector solenoid valve is energized and switches to the open state, so that the corresponding side passages of the compressed carbon dioxide storage tank and the I-shaped push rod, as well as the connection passage between the compressed carbon dioxide storage tank and the cylinder are simultaneously connected.

[0012] During the ejection power output phase: High-pressure carbon dioxide gas in the compressed carbon dioxide storage tank is rapidly released through the conduction passage: Part of the gas acts directly on the first end face of the I-shaped push rod to form the initial thrust; the other part of the gas fills the cylinder and acts on the second end face of the I-shaped push rod to form the auxiliary thrust.

[0013] Driven by the combined thrust of air pressure on both sides, the I-shaped push rod moves at high speed in a straight line along the axis of the cylinder, outputting ejection power outward to complete the ejection action.

[0014] Furthermore, an axial flow fan and an alarm are installed above the cabinet.

[0015] Furthermore, the thermal management subsystem is electrically connected to a wide-temperature-range heat pump, pressure sensor, smoke sensor, temperature sensor, axial fan, alarm device, and ejection device.

[0016] Furthermore, the battery thermal runaway early warning module is equipped with a battery thermal runaway database, which samples data from the battery compartment, including current, voltage, and temperature data. If the data exceeds a set threshold, an early warning is triggered. After the early warning is triggered, the charging circuit of the battery compartment is immediately cut off, the alarm is activated, and an alarm message is sent to the operation and maintenance platform.

[0017] The pressure sensor, smoke sensor, and temperature sensor in the battery compartment are sampled once per second; the system triggers an alarm when any of the following conditions occur in a battery compartment:

[0018] Temperature sensor temperature ≥100℃ or temperature rise ≥50℃ within 5 minutes;

[0019] The smoke sensor detected a gas concentration ≥500ppm;

[0020] Voltage > 58V;

[0021] Short-circuit current > 50A;

[0022] The single-compartment pressure sensor detected a pressure ≥0.3 MPa;

[0023] When the battery temperature exceeds 150°C, the thermal runaway ejection device is triggered. The thermal runaway battery is ejected from the battery compartment and enters the fire-fighting compartment. At the same time as ejection, the charging plug connecting the thermal runaway battery in a single battery compartment to the charging compartment is automatically disconnected, and the axial flow fan is activated to discharge the high-temperature flammable gas from the battery swapping station.

[0024] Furthermore, the battery compartment thermal management module includes a waste heat collection unit and a wide temperature range heat pump unit;

[0025] The waste heat collection unit includes a liquid cooling plate, a coolant circulation pipeline, and a circulation pump; the coolant circulation pipeline is filled with a mixed solution of water and ethylene glycol with a volume fraction of 30-40% as the cooling fluid, and the flow rate of the circulation pump is dynamically adjusted according to the waste heat temperature, with a flow rate range of 50-150L / h.

[0026] The wide-temperature-range heat pump unit operates in two modes: heating and cooling, to regulate the temperature of the battery module. In heating mode, the evaporator of the wide-temperature-range heat pump extracts heat from the air, causing the working fluid to evaporate and then enter the compressor for compression to a high-temperature, high-pressure state before flowing into the condenser. Simultaneously, the battery module coolant driven by the variable frequency circulating pump is heated in the condenser and flows to the battery module through a three-way valve to supply heat. The cooled fluid, after releasing heat, flows back to the circulating pump to complete the heating cycle. In cooling mode, the compressor compresses the working fluid to a high-temperature, high-pressure state and sends it to the condenser with a fan to dissipate heat to the air. The working fluid then flows into the evaporator. The battery-side circulating cooling fluid is cooled by the evaporator and flows to the battery module through a three-way valve for further cooling. The cooled fluid, after absorbing heat, flows back to the circulating pump to complete the cooling cycle.

[0027] Furthermore, based on the temperature of the coolant returning to the individual battery compartment, the system performs cooling treatment when the ambient temperature is greater than 25℃. As the battery temperature rises, the system adjusts the temperature by coupling the left and right phase change material plates and regulating the flow rate, thereby controlling the battery temperature at 25-35℃±1℃ during charging. When the ambient temperature is less than 25℃, based on the temperature of the coolant returning to the individual battery compartment, when the coolant return temperature is greater than 25℃ but less than 28℃, the residual heat from the battery's heat generation process is used to heat the battery. When the coolant return temperature is less than 25℃, the air source heating is activated simultaneously to heat the battery. Throughout the heating process, the phase change heat release assists in the battery heating process.

[0028] The battery compartment has two states: charging and storage. In the charging state, the refrigerant flow control valve for each battery compartment is set to a flow rate of 0.6-1.0 m³ / h. 3 / h, the temperature inside the chamber is stabilized at 25-35℃±1℃ through control; when in storage state: the refrigerant flow regulating valve is set to a flow rate of 0.2-0.5m³ / h. 3 / h, to keep the temperature inside the chamber at 25℃±2℃.

[0029] Furthermore, the outer wall of the cabinet is provided with glass wool board.

[0030] The working method of the multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets includes the following steps:

[0031] Step 1: When the battery starts to work normally, the system begins to monitor the battery status, including battery temperature, battery current, voltage data, smoke signals and pressure signals inside the chamber;

[0032] Step 2: Analyze the thermal management effect in conjunction with the temperature environment;

[0033] Step 3: When the ambient temperature is greater than 25℃, the system performs cooling treatment. As the battery temperature rises, the system absorbs heat through the coupling of the left and right phase change material plates and adjusts the flow rate to achieve battery temperature control at 25-35℃±1℃ during charging.

[0034] Step 4: When the ambient temperature is less than 25°C, determine the temperature of the battery fluid during recovery. When the coolant return temperature is greater than 25°C but less than 28°C, use the residual heat from the battery heat generation process to heat the battery. When the coolant return temperature is less than 25°C, simultaneously turn on the air source heating to heat the battery. The phase change material of the heat preservation phase change plate releases heat to assist in heating the battery.

[0035] Step 5: Determine the battery's state by combining battery voltage and current data;

[0036] Step 6: When the battery is charging, adjust the flow rate in the battery charging compartment to 0.6-1.0m. 3 / h, control the chamber temperature to 25-35℃±1℃; when the battery is in storage, adjust the flow rate in the battery charging chamber to 0.2-0.5m³ / h. 3 / h, control the warehouse temperature at 25℃±2℃;

[0037] Step 7: The system monitors the temperature inside the battery compartment and adjusts the flow rate and heat pump power accordingly;

[0038] Step 8: Issue a safety warning for the battery;

[0039] Step 9: Each sensor in the battery compartment collects data inside the battery compartment every second: specifically, the smoke sensor, temperature sensor, pressure sensor, battery current, and voltage signals inside the battery compartment;

[0040] Step 10: Determine if the warning conditions are triggered. If a warning occurs, disconnect the charging process and push the warning information to the operation and maintenance platform.

[0041] Step 11: When the battery experiences thermal runaway, the thermal runaway battery is ejected into the fire chamber within 1.5 seconds using the ejection device. At the same time as ejection, the charging plug is pulled out due to the force. Meanwhile, the exhaust fan at the top of the fire chamber is turned on to expel the high-temperature and flammable gases from the battery thermal runaway.

[0042] The beneficial effects of this invention are as follows: The thermal runaway response time of the device system is ≤2 seconds, which can effectively isolate the thermal runaway battery and eliminate the risk of personal injury and damage to adjacent batteries. The wide-temperature-range heat pump module operates within a temperature range of -30℃ to 55℃. Combined with a multi-heat source switching unit, it can adapt to different climatic conditions in northern and southern my country, solving the adaptation problem of traditional battery swapping cabinets that "do not heat up at low temperatures and do not dissipate heat at high temperatures." Precise temperature control of the battery compartment effectively extends battery life. This invention, through the zoned heat exchange unit of the terminal temperature control module, independently controls the refrigerant flow in the charging area and the battery storage area, stabilizing the charging area temperature at 25-35℃±1℃ and the storage area temperature at 25℃±2℃. Attached Figure Description

[0043] Figure 1 Front view of an electric bicycle battery swapping station.

[0044] Figure 2 Side view of the layout of an electric bicycle battery swapping station.

[0045] Figure 3 Internal components of a single battery compartment.

[0046] Figure 4 Design drawing of the catapult system.

[0047] Figure 5 Operation diagram of thermal management and safety protection system of electric battery swapping station.

[0048] Figure 6 Schematic diagram of a wide-temperature-range heat pump.

[0049] In the diagram: 1. Wide-temperature-range heat pump; 2. Fire compartment; 3. Battery compartment; 4. Glass wool board; 5. Axial flow fan; 6. Alarm device; 7. Ejection device; 8. Pressure sensor; 9. Smoke sensor; 10. Front door; 11. Liquid cooling plate; 12. Rear door; 13. Temperature sensor; 14. Compressed carbon dioxide storage tank; 15. Ejection solenoid valve; 16. Push rod; 17. Cavity; 18. Cylinder; 19. Individual battery; 20. Phase change material plate; 21. Refrigerant flow regulating valve; 22. Three-way valve; 23. Variable frequency circulating pump; 24. Circulation pipeline; 25. Second heat exchanger; 26. First heat exchanger; 27. Compressor; 28. Fan; 29. ​​Front and rear door linkage control module. Detailed Implementation

[0050] The present invention will be specifically described below through embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention, but are not limited thereto, unless otherwise stated.

[0051] The specific embodiments of the present invention are described in detail below with reference to the technical solutions:

[0052] This invention utilizes a wide-temperature-range heat pump liquid cooling system design to achieve full-condition temperature control of "high-efficiency heating + precise heat dissipation"—it not only uses a wide-temperature-range heat pump to solve the problems of high heating energy consumption and failure at extreme low temperatures in winter, but also regulates the battery compartment temperature through the heat storage and release of phase change materials, ultimately achieving the goal of "energy-saving heating in winter, high-efficiency heat dissipation in summer, and stable temperature control throughout the year" for the battery swapping cabinet.

[0053] Figures 1 to 4 The multi-dimensional thermal management and safety protection system of the electric bicycle battery swapping cabinet is shown. It includes a cabinet, a fire compartment 2 and an axial flow fan 5. The cabinet includes a battery area and an ejection area above the fire compartment 2.

[0054] The battery area is divided into several battery compartments 3, with a front door 9 and a rear door 12 at the front and back of each battery compartment 3, respectively. The side walls of the battery compartment 3 are made of phase change material plates 20, and the bottom of the battery compartment 3 is equipped with a liquid cooling plate 10 with a temperature sensor 13 installed. Each battery compartment 3 contains a single battery 19, and a pressure sensor 8 and a smoke sensor 9 are installed in the battery compartment 3 above it. At the linkage control node between the front door 9 and the rear door 11, a front and rear door linkage control module 29 is configured. Its linkage control logic is as follows: when the front door 9 is in the open state, the front and rear door linkage control module 29 controls the rear door 11 to remain locked and cannot be opened; when the front door 9 is in the locked closed state, the front and rear door linkage control module 29 releases the locking restriction on the rear door 11, making the rear door 11 openable.

[0055] An ejection device 7 is installed between the front door 9 and the individual battery 19. The ejection device 7 includes a compressed carbon dioxide storage tank 14, an ejection solenoid valve 15, a push rod 16, and a cylinder 18. A cavity 17 is provided between the compressed carbon dioxide storage tank 14 and the first end face 16a of the I-shaped push rod 16. The ejection solenoid valve 15 is installed at the opening of the compressed carbon dioxide storage tank 14. One end of the cylinder 18 is fixed to the front door 10, and the other end acts on the second end face 16b of the push rod 16. After the ejection device 7 is triggered, the individual battery 19 is pushed into the fire compartment 2 through the rear door 12.

[0056] The system is also equipped with a wide temperature range heat pump 1 on the outside of the cabinet. The wide temperature range heat pump 1 is connected to the liquid cooling plate 10 through a pipeline to deliver the temperature control working fluid to the liquid cooling plate 10.

[0057] The system also includes a thermal management subsystem, which comprises a battery thermal runaway early warning module, a battery thermal runaway control module, a battery compartment thermal management module, and an end-point temperature control module.

[0058] An axial flow fan 5 and an alarm 17 are installed on the top of the cabinet. Glass wool board 4 is installed on the outer wall of the cabinet.

[0059] The thermal management subsystem is electrically connected to the wide-temperature-range heat pump 1, pressure sensor 8, smoke sensor 9, temperature sensor 13, axial flow fan 5, alarm device 6, and ejection device 7.

[0060] The operation of the ejection device 7 is as follows:

[0061] Initial state: The compressed carbon dioxide storage tank 14 is pre-filled with high-pressure carbon dioxide gas at a preset pressure; the solenoid valve 15 is in the normally closed state and is sealed between the compressed carbon dioxide storage tank 14 and the cavity 17, and the high-pressure gas in the compressed carbon dioxide storage tank 14 flows to the push rod side and the cylinder side; the I-shaped push rod 16 is in the initial reset position, and the cylinder 18 is kept at normal pressure.

[0062] Triggering phase: When the system receives a preset system trigger thermal runaway signal, the ejection solenoid valve 15 is energized and switches to the open state, so that the corresponding side passages of the compressed carbon dioxide storage tank 14 and the I-shaped push rod 16, as well as the communication passage between the compressed carbon dioxide storage tank 14 and the cylinder 18 are synchronously connected.

[0063] During the ejection power output phase: the high-pressure carbon dioxide gas in the compressed carbon dioxide storage tank 14 is rapidly released through the conduction passage: part of the gas acts directly on the first end face 16a of the I-shaped push rod 16 to form the initial thrust; the other part of the gas fills the cylinder 18 and acts on the second end face 16b of the I-shaped push rod 16 to form the auxiliary thrust.

[0064] Driven by the combined thrust of air pressure on both sides, the I-shaped push rod 16 moves at high speed in a straight line along the axis of the cylinder 18, outputting ejection power outward to complete the ejection action.

[0065] The battery thermal runaway early warning module is equipped with a battery thermal runaway database. It samples data from the battery compartment, including current, voltage, and temperature data. If the data exceeds the set threshold, an early warning is triggered. After the early warning is triggered, the charging circuit of the battery compartment is immediately cut off, the alarm is activated, and an alarm message is sent to the operation and maintenance platform.

[0066] The pressure sensor 8, smoke sensor 9, and temperature sensor 13 in battery compartment 3 are sampled at a frequency of 1 time / second; the system triggers an alarm when any of the following conditions occur in a battery compartment:

[0067] Temperature sensor temperature ≥100℃ or temperature rise ≥50℃ within 5 minutes;

[0068] The smoke sensor detected a gas concentration ≥500ppm;

[0069] Voltage > 58V;

[0070] Short-circuit current > 50A;

[0071] The single-compartment pressure sensor detected a pressure ≥0.3 MPa;

[0072] When the battery temperature exceeds 150°C, the thermal runaway ejection device is triggered. The thermal runaway battery is ejected from the battery compartment and enters the fire-fighting compartment. At the same time as ejection, the charging plug connecting the thermal runaway battery in a single battery compartment to the charging compartment is automatically disconnected, and the axial flow fan is activated to discharge the high-temperature flammable gas from the battery swapping station.

[0073] The battery compartment thermal management module includes a waste heat harvesting unit and a wide-temperature-range heat pump unit;

[0074] The waste heat collection unit includes a liquid cooling plate, a coolant circulation pipeline, and a circulation pump. The coolant circulation pipeline is filled with a mixed solution of water and ethylene glycol with a volume fraction of 30-40% as the cooling fluid. The flow rate of the circulation pump is dynamically adjusted according to the waste heat temperature, with a flow rate range of 50-150 L / h.

[0075] The wide-temperature-range heat pump unit operates in two modes: heating and cooling, to regulate the temperature of the battery module. In heating mode, the evaporator of the wide-temperature-range heat pump extracts heat from the air, causing the working fluid to evaporate and then enter the compressor for compression to a high-temperature, high-pressure state before flowing into the condenser. Simultaneously, the battery module coolant driven by the variable frequency circulating pump is heated in the condenser and flows to the battery module through a three-way valve to supply heat. The cooled fluid, after releasing heat, flows back to the circulating pump to complete the heating cycle. In cooling mode, the compressor compresses the working fluid to a high-temperature, high-pressure state and sends it to the condenser with a fan to dissipate heat to the air. The working fluid then flows into the evaporator. The battery-side circulating cooling fluid is cooled by the evaporator and flows to the battery module through a three-way valve for further cooling. The cooled fluid, after absorbing heat, flows back to the circulating pump to complete the cooling cycle.

[0076] Analysis based on the temperature of the coolant returning to the individual battery compartment: When the ambient temperature is above 25℃, the system performs cooling treatment. As the battery temperature rises, the system adjusts the temperature by coupling the left and right phase change material plates and regulating the flow rate, thereby controlling the battery temperature at 25-35℃±1℃ during charging. When the ambient temperature is below 25℃, based on the temperature of the coolant returning to the individual battery compartment, when the coolant return temperature is above 25℃ but below 28℃, the residual heat from the battery's heat generation process is used to heat the battery. When the coolant return temperature is below 25℃, air source heating is simultaneously activated to heat the battery. Throughout the heating process, the phase change heat release assists in the battery heating process.

[0077] The battery compartment has two states: charging and storage. In the charging state, the refrigerant flow control valve for each battery compartment is set to a flow rate of 0.6-1.0 m³ / h. 3 / h, the temperature inside the chamber is stabilized at 25-35℃±1℃ through control; when in storage state: the refrigerant flow regulating valve is set to a flow rate of 0.2-0.5m³ / h. 3 / h, to keep the temperature inside the chamber at 25℃±2℃.

[0078] The working method of the multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets includes the following steps:

[0079] Step 1: When the battery starts to work normally, the system begins to monitor the battery status, including battery temperature, battery current, voltage data, smoke signals and pressure signals inside the chamber;

[0080] Step 2: Analyze the thermal management effect in conjunction with the temperature environment;

[0081] Step 3: When the ambient temperature is greater than 25℃, the system performs cooling treatment. As the battery temperature rises, the system absorbs heat through the coupling of the left and right phase change material plates and adjusts the flow rate to achieve battery temperature control at 25-35℃±1℃ during charging.

[0082] Step 4: When the ambient temperature is less than 25°C, determine the temperature of the battery fluid during recovery. When the coolant return temperature is greater than 25°C but less than 28°C, use the residual heat from the battery heat generation process to heat the battery. When the coolant return temperature is less than 25°C, simultaneously turn on the air source heating to heat the battery. The phase change material of the heat preservation phase change plate releases heat to assist in heating the battery.

[0083] Step 5: Determine the battery's state by combining battery voltage and current data;

[0084] Step 6: When the battery is charging, adjust the flow rate in the battery charging compartment to 0.6-1.0m. 3 / h, control the chamber temperature to 25-35℃±1℃; when the battery is in storage, adjust the flow rate in the battery charging chamber to 0.2-0.5m³ / h. 3 / h, control the warehouse temperature at 25℃±2℃;

[0085] Step 7: The system monitors the temperature inside the battery compartment and adjusts the flow rate and heat pump power accordingly;

[0086] Step 8: Issue a safety warning for the battery;

[0087] Step 9: Each sensor in the battery compartment collects data inside the battery compartment every second: specifically, the smoke sensor, temperature sensor, pressure sensor, battery current, and voltage signals inside the battery compartment;

[0088] Step 10: Determine if the warning conditions are triggered. If a warning occurs, disconnect the charging process and push the warning information to the operation and maintenance platform.

[0089] Step 11: When the battery experiences thermal runaway, the thermal runaway battery is ejected into the fire chamber within 1.5 seconds using the ejection device. At the same time as ejection, the charging plug is pulled out due to the force. Meanwhile, the exhaust fan at the top of the fire chamber is turned on to expel the high-temperature and flammable gases from the battery thermal runaway.

[0090] The battery status is determined by the current and voltage signals from the temperature sensor 13, pressure sensor 8, smoke sensor 9, and battery 19. When the battery is in an abnormal state, including short circuit, overcharge or over-discharge, overcurrent, over- or under-voltage, over-temperature, differential voltage, communication abnormality, etc., the power is automatically cut off and alarm information is reported. When the battery temperature is too high, the alarm device 6 is used to warn the surrounding personnel to prevent injury or death.

[0091] The front door 10 and rear door 11 of the entire battery compartment are linked. When the front door 10 is opened, i.e., when the user opens the front door 10 to replace the battery, the rear door 11 is closed. When the user closes the front door 10 after the battery replacement, the rear door 11 can be opened, thus ensuring that the battery device is not directly pushed into the fire compartment and that the runaway battery can be ejected in time in the event of thermal runaway. The system monitors pressure and temperature changes through the temperature sensor 13 inside the battery pack and the pressure sensor 8 in the battery compartment. When the temperature is ≥150℃, the thermal runaway battery ejection mechanism is driven by the gas storage device 14 as the core. When the system determines that the battery is to be ejected, CO2 expands in the cavity 17 through the solenoid valve 15 and pushes the push rod 16 forward, ejecting the battery 19 into and out of the battery compartment fire passage and into the fire-fighting liquid 2 located below the battery replacement cabinet, thereby isolating the thermal runaway battery, suppressing the spread of thermal runaway and extinguishing the runaway battery. Turn on the fan 5 located above the pipe to discharge the high-temperature exhaust gas in time and prevent further damage.

[0092] The external design of the battery swapping cabinet features a glass wool panel 4, primarily for heat insulation and flame retardancy of the battery compartments. Each battery compartment has a 6:4 mass ratio phase change material insulation board 20 on both sides, consisting of disodium hydrogen phosphate dodecahydrate (DHPD) and sodium carbonate decahydrate (SCD), with a phase change temperature of 25℃ and good stability. This insulation mainly assists the wide-temperature-range heat pump 1 liquid cooling system, addressing the waste heat generated during battery charging and discharging. Especially in harsh winter conditions, it converts waste heat into insulating heat, reducing operating power, and also possesses excellent flame retardant properties.

[0093] The battery compartment thermal management module includes a waste heat acquisition unit, an air source acquisition unit, and a heat source switching unit;

[0094] The waste heat collection unit includes a liquid cooling plate 11, a coolant circulation pipeline 24, and a circulation pump 23. The liquid cooling plate is arranged close to the bottom wall of the battery storage compartment. The coolant circulation pipeline 24 is filled with a 30-40% concentration water-ethylene glycol solution as a cooling fluid. The circulation pump is a variable frequency pump 23 in the wide temperature range heat pump 1, and the flow rate can be dynamically adjusted according to the waste heat temperature (50-150L / h).

[0095] The air source acquisition unit includes a wide-temperature-range heat pump module 1, which is equipped with a variable frequency circulating pump 23, a first heat exchanger 26, a second heat exchanger 25, and a fan 28; the operating temperature range of the wide-temperature-range heat pump module is -30℃ to 55℃.

[0096] The heat source switching unit includes a three-way solenoid valve 22 and a temperature sensor 13; the response time of the three-way solenoid valve is ≤0.5 seconds, and the accuracy of the temperature sensor is ±0.5℃, and it is arranged at the outlet end of the waste heat collection unit.

[0097] The refrigerant flow regulating valve 21 can independently control the refrigerant flow (0.2-1.0 m³) in each zone. 3 / h), so that the temperature of the charging area is controlled at 25-35℃±1℃ and the temperature of the storage area is controlled at 25℃±2℃;

[0098] Example 1

[0099] This embodiment uses a community-type electric bicycle battery swapping cabinet as an application scenario to achieve 20-compartment battery storage and swapping functions, serving common 48V / 20Ah electric bicycle lithium batteries. It achieves full-condition temperature control and thermal runaway protection through a patented technology solution. The following are detailed implementation details.

[0100] System core components:

[0101] Dual heat source heat pump: It adopts a wide temperature range heat pump 1 with an operating temperature of -30℃ to 55℃, and is equipped with a variable frequency circulating pump 23.

[0102] Axial flow fans: 5 low-noise axial flow fans, a total of 4 units, are selected and placed on the top of the battery swapping cabinet.

[0103] Sensors: Each compartment is equipped with one temperature sensor 13 (accuracy ±0.5℃), one smoke sensor 9, and one pressure sensor 8 (range 0-1MPa).

[0104] Other components: Each compartment is equipped with one ejection device 7 (stroke 80mm, response time ≤1.5 seconds), phase change material heat insulation plate 20, three-way solenoid valve 22 (response time ≤0.5 seconds), and liquid cooling plate 11 (heat dissipation power ≥150W / m). 2 ).

[0105] 1. Battery thermal runaway early warning device

[0106] Hardware Configuration: The central control system is equipped with a "Battery Thermal Runaway Database" (containing experimental data on thermal runaway of lithium batteries under different conditions, covering 7 types of abnormal characteristic thresholds such as short circuit and overcharge), with each compartment's sensor sampling frequency being 1 time / second. Warning Logic: The system triggers a warning when any of the following conditions occur in a battery compartment:

[0107] Temperature sensor 13: Temperature ≥100℃ or temperature rise ≥50℃ within 5 minutes;

[0108] Smoke sensor 9 detected a gas concentration ≥500ppm;

[0109] Voltage > 58V

[0110] Short-circuit current (>50A).

[0111] Action executed: After the warning is triggered, the system immediately cuts off the charging circuit of the compartment, activates the audible and visual alarm 6 on the top of the battery swapping cabinet, and sends alarm information (including compartment number, anomaly type, and real-time data) to the operation and maintenance platform.

[0112] 2. Battery thermal runaway control module

[0113] Triggering conditions: When the pressure sensor 8 in a certain compartment detects a pressure ≥ 0.3 MPa and a temperature ≥ 150℃, the system determines it to be in a "thermal runaway state" and initiates the control process. Ejection device 7 is activated: The thermal runaway battery 9 is ejected from the battery compartment 3 via the ejection device 7 and slides along the fire escape route into the underground fire-fighting liquid pool 2 below the battery swapping cabinet; Disconnection and venting:

[0114] At the same time as ejection, the charging plug is automatically disconnected (disconnection time ≤ 0.5 seconds), and the top duct fan 5 of the chamber is turned on to discharge high-temperature flammable exhaust gas (such as CO, SO2) to the outside through the 150mm diameter exhaust pipe.

[0115] 3. Phase Change Material Plate: Material Preparation: The phase change material is a mixture of disodium hydrogen phosphate dodecahydrate (DHPD) and sodium carbonate decahydrate (SCD) at a mass ratio of 6:4, with 70% EHS expanded perlite (EP) as the matrix, pressed into a 20mm thick heat insulation plate. The phase change temperature is 25℃, and the latent heat of phase change is ≥200kJ / kg. 20mm of phase change heat insulation plate is pasted onto the inner walls of both sides of each compartment. When the battery generates residual heat during charging and discharging, the heat insulation plate absorbs the residual heat and undergoes a phase change, preventing heat transfer to adjacent battery compartments. When the ambient temperature is ≤25℃, the phase change material releases the stored residual heat to assist in the insulation of the battery compartment, maintaining the internal temperature above 25℃ and reducing the heating power of the heat pump.

[0116] 4. Battery compartment thermal management module

[0117] Waste Heat Collection Unit: Liquid Cooling Plate Arrangement: One liquid cooling plate 11 is arranged at the bottom of each compartment, and the pipeline is filled with a 35% concentration water-ethylene glycol solution (freezing point -25℃, boiling point 108℃); Circulation Pump Control: A variable frequency circulation pump 23 is used, and the flow rate is dynamically adjusted according to the waste heat temperature. When the liquid cooling plate outlet temperature is ≥30℃, the flow rate is adjusted to 150L / h; when the outlet temperature is ≤25℃, the flow rate is reduced to 50L / h. Air Source Collection Unit: In summer, the wide temperature range heat pump unit 1 exhausts heat to the outside through the fan 28, and absorbs heat from the outside in winter. Heat Source Switching Unit: A three-way solenoid valve 22 is installed at the junction of the waste heat collection unit and the air source collection unit. When the ambient temperature is less than 25℃, the temperature of the refrigerant during recovery is judged. When the coolant return temperature is greater than 25℃ but less than 28℃, the waste heat from the battery heat generation process is used to heat the battery. When the coolant return temperature is less than 25℃, the air source heating is turned on simultaneously to heat the battery. Phase change material plates utilize phase change heat release to assist in heating the battery.

[0118] 5. Terminal temperature control module

[0119] The overall battery compartment is divided into charging and storage states due to the different operating conditions of each battery. When in charging state: the refrigerant flow regulating valve 21 is set to a flow rate of 0.6-1.0 m³ / h. 3 / h, the internal temperature is stabilized at 25-35℃±1℃ (the optimal temperature range for the battery during charging) through control; when in storage state: the refrigerant flow regulating valve 21 is set to a flow rate of 0.2-0.5m³ / h. 3 / h, keeping the internal temperature of the battery compartment at 25℃±2℃ (the safe temperature range for battery storage). Intelligent insulation unit: The outer wall of the battery swapping cabinet is wrapped with 50mm thick glass wool board 4 (thermal conductivity ≤0.03W / (m・K)), and the battery compartment is insulated by phase change heat storage module 20.

[0120] When using the above technical solution, the following steps are included:

[0121] Step 1: After the battery starts working normally, the system immediately starts battery status monitoring, and collects battery temperature 13, current and voltage data in real time, as well as smoke signal 9 and pressure signal 8 in the battery compartment.

[0122] Step 2: Combine ambient temperature data to conduct thermal management effectiveness analysis and evaluation.

[0123] Step 3: When the ambient temperature is higher than 25℃, the system starts the cooling mode; as the battery temperature rises, heat is absorbed by coupling the phase change material plates 20 on both sides, and the flow rate 23 is adjusted in coordination to ensure that the battery temperature is stably controlled within the range of 25-35℃±1℃ during charging.

[0124] Step 4: When the ambient temperature is below 25℃, the system first determines the coolant return temperature: if the return temperature is in the range of 25-28℃, the battery heats up by utilizing the residual heat generated by the battery; if the return temperature is below 25℃, the air source heating mode 1 is activated simultaneously, and auxiliary heating is achieved by utilizing the heat release of the phase change material 20 in the heat-insulating phase change plate.

[0125] Step 5: Combine the real-time collected battery voltage and current data to determine the current working state of the battery (charging / storage).

[0126] Step 6: Adjust the corresponding parameters according to the judgment result: When the battery is charging, adjust the flow rate in the battery charging compartment to 0.6-1.0m³ using the refrigerant regulating valve 21. 3 The flow rate is maintained at 25-35℃±1℃ per hour; when in storage, the flow rate is adjusted to 0.2-0.5 m³ / h. 3 / h, the warehouse temperature is controlled within the range of 25℃±2℃.

[0127] Step 7: The system continuously monitors the temperature changes inside the battery compartment and dynamically adjusts the flow parameters and heat pump operating power to maintain a stable compartment temperature.

[0128] Step 8: Simultaneously conduct battery safety status early warning monitoring.

[0129] Step 9: Sensors in each battery compartment collect data at a frequency of 1 time per second, specifically covering smoke, temperature, pressure sensing signals, and battery current and voltage signals.

[0130] Step 10: The system determines in real time whether a safety warning condition has been triggered: If a warning is triggered, the charging circuit is immediately cut off, the charging operation is stopped, and the warning information is pushed to the operation and maintenance management platform simultaneously.

[0131] Step 11: In the event of battery thermal runaway, ejection device 7 will activate within 1.5 seconds, quickly launching the thermal runaway battery ejector 19 into the dedicated fire chamber 2. During ejection, the charging plug will be automatically pulled out by mechanical force. Simultaneously, the exhaust fan 5 at the top of the fire chamber will immediately start, quickly expelling the high-temperature flammable gas generated by thermal runaway and eliminating the risk of deflagration.

[0132] Step 12: Throughout the entire process described above, the system continuously monitors the battery compartment and battery status in real time to ensure safe and controllable operation.

[0133] The above embodiments are only used to illustrate the present invention. Any equivalent transformations and improvements made on the basis of the technical solutions of the present invention should not be excluded from the protection scope of the present invention.

Claims

1. A multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets, comprising a cabinet body, a fire-fighting compartment (2), and an axial flow fan (5), characterized in that: The cabinet includes a battery area and a launch area above the fire compartment (2); The battery area is divided into several battery compartments (3). A front compartment door (9) and a rear compartment door (12) are provided at the front and back of the battery compartments (3), respectively. The two side walls of the battery compartments (3) are phase change material plates (20). A liquid cooling plate (10) with a temperature sensor (13) is provided at the bottom of the battery compartments (3). A single battery (19) is provided in the battery compartment (3). A pressure sensor (8) and a smoke sensor (9) are provided in the battery compartment (3) above it. At the linkage control node between the front compartment door (9) and the rear compartment door (11), a front and rear compartment door linkage control module (29) is configured. Its linkage control logic is as follows: when the front compartment door (9) is in the open state, the front and rear compartment door linkage control module (29) controls the rear compartment door (11) to remain in the locked state and cannot be opened; when the front compartment door (9) is in the locked closed state, the front and rear compartment door linkage control module (29) releases the locking restriction on the rear compartment door (11) so that the rear compartment door (11) has the conditions to be opened. An ejection device (7) is provided between the front door (9) and the individual battery (19). The ejection device (7) includes a compressed carbon dioxide storage tank (14), an ejection solenoid valve (15), a push rod (16), and a cylinder (18). A cavity (17) is provided between the compressed carbon dioxide storage tank (14) and the first end face (16a) of the I-shaped push rod (16). An ejection solenoid valve (15) is provided at the opening of the compressed carbon dioxide storage tank (14). One end of the cylinder (18) is fixed on the front door (10), and the other end acts on the second end face (16b) of the push rod (16). After the ejection device (7) is triggered, the individual battery (19) is pushed into the fire compartment (2) through the rear door (12). A wide-temperature-range heat pump (1) is also installed on the outside of the cabinet of the system. The wide-temperature-range heat pump (1) is connected to the liquid cooling plate (10) through a pipeline to deliver the temperature-controlled working fluid to the liquid cooling plate (10). The system also includes a thermal management subsystem, which comprises a battery thermal runaway early warning module, a battery thermal runaway control module, a battery compartment thermal management module, and an end-point temperature control module.

2. The multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets according to claim 1, characterized in that: The operation process of the ejection device (7) is as follows: Initial state: The compressed carbon dioxide storage tank (14) is pre-filled with high-pressure carbon dioxide gas at a preset pressure; the solenoid valve (15) is in a normally closed state and is sealed between the compressed carbon dioxide storage tank (14) and the cavity (17), allowing the high-pressure gas in the compressed carbon dioxide storage tank (14) to flow to the push rod side and the cylinder side; the I-shaped push rod (16) is in the initial reset position, and the cylinder (18) is kept at normal pressure. Triggering phase: When the system receives a preset system trigger thermal runaway signal, the ejection solenoid valve (15) is energized and switches to the open state, so that the corresponding side passages of the compressed carbon dioxide storage tank (14) and the I-shaped push rod (16), as well as the connecting passage between the compressed carbon dioxide storage tank (14) and the cylinder (18) are simultaneously connected. During the ejection power output stage: the high-pressure carbon dioxide gas in the compressed carbon dioxide storage tank (14) is rapidly released through the conduction passage: part of the gas acts directly on the first end face (16a) of the I-shaped push rod (16) to form the initial thrust; the other part of the gas is filled into the cylinder (18) and acts on the second end face (16b) of the I-shaped push rod (16) to form the auxiliary thrust. Driven by the combined thrust of air pressure on both sides, the I-shaped push rod (16) moves at high speed along the axis of the cylinder (18), outputting ejection power to complete the ejection action.

3. The multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets according to claim 2, characterized in that: An axial flow fan (5) and an alarm (17) are installed above the cabinet.

4. The multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets according to claim 3, characterized in that: The thermal management subsystem is electrically connected to the wide-temperature-range heat pump (1), pressure sensor (8), smoke sensor (9), temperature sensor (13), axial flow fan (5), alarm device (6), and ejection device (7).

5. The multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets according to claim 4, characterized in that: The battery thermal runaway early warning module is equipped with a battery thermal runaway database. It samples data from the battery compartment, including current, voltage, and temperature data. If the data exceeds the set threshold, an early warning is triggered. After the early warning is triggered, the charging circuit of the battery compartment is immediately cut off, the alarm is activated, and an alarm message is sent to the operation and maintenance platform. The pressure sensor (8), smoke sensor (9), and temperature sensor (13) of the battery compartment (3) are sampled at a frequency of 1 time / second; the system triggers an alarm when any of the following conditions occur in a battery compartment: Temperature sensor temperature ≥100℃ or temperature rise ≥50℃ within 5 minutes; The smoke sensor detected a gas concentration ≥500ppm; Voltage > 58V; Short-circuit current > 50A; The single-compartment pressure sensor detected a pressure ≥0.3 MPa; When the battery temperature exceeds 150°C, the thermal runaway ejection device is triggered. The thermal runaway battery is ejected from the battery compartment and enters the fire-fighting compartment. At the same time as ejection, the charging plug connecting the thermal runaway battery in a single battery compartment to the charging compartment is automatically disconnected, and the axial flow fan is activated to discharge the high-temperature flammable gas from the battery swapping station.

6. The multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets according to claim 5, characterized in that: The battery compartment thermal management module includes a waste heat collection unit and a wide temperature range heat pump unit. The waste heat collection unit includes a liquid cooling plate, a coolant circulation pipeline, and a circulation pump; the coolant circulation pipeline is filled with a mixed solution of water and ethylene glycol with a volume fraction of 30-40% as the cooling fluid, and the flow rate of the circulation pump is dynamically adjusted according to the waste heat temperature, with a flow rate range of 50-150L / h. The wide-temperature-range heat pump unit operates in two modes: heating and cooling, to regulate the temperature of the battery module. In heating mode, the evaporator of the wide-temperature-range heat pump extracts heat from the air, causing the working fluid to evaporate and enter the compressor, where it is compressed to a high-temperature, high-pressure state before flowing into the condenser. Simultaneously, the battery module coolant, driven by the variable frequency circulation pump, is heated in the condenser and flows through a three-way valve to supply heat to the battery module. The cooled fluid, after releasing heat, flows back to the circulation pump to complete the heating cycle. In cooling mode, the compressor compresses the working fluid to a high-temperature, high-pressure state and sends it to the condenser equipped with a fan to dissipate heat to the air. Subsequently, the working fluid flows into the evaporator. After being cooled by the evaporator, the circulating cooling fluid on the battery side flows to the battery module through the three-way valve for further cooling. The cooled fluid, after absorbing heat, flows back to the circulating pump to complete the refrigeration cycle.

7. The multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets according to claim 6, characterized in that: Analysis based on the temperature of the coolant returning to the individual battery compartment: When the ambient temperature is above 25℃, the system performs cooling treatment. As the battery temperature rises, the system adjusts the temperature by coupling the left and right phase change material plates and regulating the flow rate, thereby controlling the battery temperature at 25-35℃±1℃ during charging. When the ambient temperature is below 25℃, based on the temperature of the coolant returning to the individual battery compartment, when the coolant return temperature is above 25℃ but below 28℃, the residual heat from the battery's heat generation process is used to heat the battery. When the coolant return temperature is below 25℃, air source heating is simultaneously activated to heat the battery. Throughout the heating process, the phase change heat release assists in the battery heating process. The battery compartment is divided into charging state and storage state. The battery compartment in charging state: the refrigerant flow regulating valve in single battery compartment adjusts the refrigerant flow in single battery compartment, and the valve is set to 0.6-1.0 m 3 / h, and the temperature in the compartment is stabilized at 25-35℃±1℃ by control; in storage state: the refrigerant flow regulating valve is set to 0.2-0.5 m 3 / h, and the temperature in the compartment is controlled at 25℃±2℃.

8. The multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets according to claim 7, characterized in that: The outer wall of the cabinet is fitted with glass wool board (4).

9. The working method of the multi-dimensional thermal management and safety protection system for electric bicycle battery swapping cabinets according to claim 8, characterized in that, Includes the following steps: Step 1: When the battery starts to work normally, the system begins to monitor the battery status, including battery temperature, battery current, voltage data, smoke signals and pressure signals inside the chamber; Step 2: Analyze the thermal management effect in conjunction with the temperature environment; Step 3: When the ambient temperature is greater than 25℃, the system performs cooling treatment. As the battery temperature rises, the system absorbs heat through the coupling of the left and right phase change material plates and adjusts the flow rate to achieve battery temperature control at 25-35℃±1℃ during charging. Step 4: When the ambient temperature is less than 25°C, determine the temperature of the battery fluid during recovery. When the coolant return temperature is greater than 25°C but less than 28°C, use the residual heat from the battery heat generation process to heat the battery. When the coolant return temperature is less than 25°C, simultaneously turn on the air source heating to heat the battery. The phase change material in the thermal insulation phase change plate releases heat, which assists in heating the battery. Step 5: Determine the battery's state by combining battery voltage and current data; Step 6: When the battery is charging, adjust the flow rate in the battery charging compartment to 0.6-1.0m. 3 / h, control the chamber temperature to 25-35℃±1℃; when the battery is in storage, adjust the flow rate in the battery charging chamber to 0.2-0.5m³ / h. 3 / h, control the warehouse temperature at 25℃±2℃; Step 7: The system monitors the temperature inside the battery compartment and adjusts the flow rate and heat pump power accordingly; Step 8: Issue a safety warning for the battery; Step 9: Each sensor in the battery compartment collects data inside the battery compartment every second: specifically, the smoke sensor, temperature sensor, pressure sensor, battery current, and voltage signals inside the battery compartment; Step 10: Determine if the warning conditions are triggered. If a warning occurs, disconnect the charging process and push the warning information to the operation and maintenance platform. Step 11: When the battery experiences thermal runaway, the thermal runaway battery is ejected into the fire chamber within 1.5 seconds using the ejection device. At the same time as ejection, the charging plug is pulled out due to the force. Meanwhile, the exhaust fan at the top of the fire chamber is turned on to expel the high-temperature and flammable gases from the battery thermal runaway.

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