Thermal management method and thermal management system of battery for battery changing ship

Abstract

The invention provides a battery heat management method and a heat management system for a battery changing ship, and relates to the technical field of battery heat management, and the method comprises the following steps: judging a current working mode of a battery box; obtaining the current highest temperature and the current lowest temperature of a plurality of single batteries in the battery box; and determining and executing a temperature control strategy, a power reduction strategy and a battery box switching strategy matched with the current working mode of the battery box based on the highest temperature and the lowest temperature. The current temperature condition of the battery box can be better monitored by acquiring the current highest temperature and the current lowest temperature of the plurality of single batteries in the battery box, and a temperature control strategy matched with the current working mode of the battery box is combined, so that the batteries can be ensured to operate in the optimal temperature range, and the thermal management efficiency of the batteries is improved. When the battery box has an overheating risk, the safety and reliability of battery thermal management can be improved through a power reduction strategy and a battery box switching strategy.

Description

Technical Field

[0001] The present application relates to the technical field of battery thermal management, and more specifically, to a battery thermal management method and thermal management system for battery-exchange ships. Background Art

[0002] Battery-swap marine battery cabinets provide ships with fast battery replacement services. With the increasing attention to green travel and technological progress, the demand for them is growing rapidly, especially for battery energy consumption, safety and thermal management efficiency. Temperature affects battery performance. Too high or too low temperature will lead to performance degradation or cause safety risks. An efficient thermal management system can ensure that the battery operates within the optimal temperature range, extend its life, and improve safety and reliability. As ships face complex environmental conditions, higher requirements are placed on the thermal management system. Therefore, it is crucial to develop innovative thermal management strategies for battery-swap marine battery cabinets.

[0003] At present, although some thermal management technologies have been applied to energy storage batteries, there are often problems such as high battery energy consumption, poor thermal management efficiency, and poor safety, which make it difficult to meet the thermal management needs of ship battery cabinets.

[0004] Therefore, how to improve battery thermal management efficiency and ensure safety and reliability is a technical problem that needs to be urgently solved by technical personnel in this field. Summary of the invention

[0005] The purpose of this application is to provide a battery thermal management method and thermal management system for battery swapping ships to improve the battery thermal management efficiency and ensure safety and reliability.

[0006] In order to achieve the above purpose, the technical solution adopted in this application is as follows:

[0007] On the one hand, the present application provides a battery thermal management method for a battery-swap ship, which is applied to a thermal management system, and the method includes:

[0008] Determine the current working mode of the battery box; wherein the working mode includes a charging mode and a discharging mode;

[0009] Obtaining the current maximum temperature and minimum temperature of multiple battery cells in the battery box;

[0010] Based on the maximum temperature and the minimum temperature, a temperature control strategy, a power reduction strategy, and a battery box switching strategy that match the current operating mode of the battery box are determined and executed.

[0011] Furthermore, the method for determining the current working mode of the battery box includes:

[0012] If a charging wake-up signal is detected, determining that the current working mode of the battery box is the charging mode;

[0013] If the charging wake-up signal is not detected, it is determined that the current operating mode of the battery box is the discharging mode.

[0014] Further, when it is determined that the current working mode of the battery box is the charging mode, based on the maximum temperature and the minimum temperature, the method for determining and executing a temperature control strategy, a power reduction strategy, and a battery box switching strategy that match the current working mode of the battery box includes:

[0015] When the maximum temperature is less than the first temperature threshold, executing a first charging temperature control strategy for the battery box according to the minimum temperature;

[0016] When the maximum temperature is ≥ the first temperature threshold, executing a second charging temperature control strategy, a charging power reduction strategy and a charging battery box switching strategy on the battery box according to the minimum temperature and the maximum temperature;

[0017] Among them, the first temperature threshold>the upper limit value of the optimal charging and discharging temperature range.

[0018] Further, when the maximum temperature is less than the first temperature threshold, the method for executing the first charging temperature control strategy on the battery box according to the minimum temperature includes:

[0019] When the lowest temperature is ≥ the second temperature threshold, the battery box is charged normally;

[0020] When the lowest temperature is less than the second temperature threshold, the heating mode is turned on, and the battery box is charged according to the charging comparison table, until the lowest temperature is greater than or equal to the third temperature threshold, the heating mode is turned off, and the battery box is charged normally;

[0021] The second temperature threshold is the lower limit of the optimal charge and discharge operating temperature range, and the second temperature threshold < the third temperature threshold < the first temperature threshold.

[0022] Further, when the maximum temperature is ≥ the first temperature threshold, the method for executing the second charging temperature control strategy, the charging power reduction strategy and the charging battery box switching strategy on the battery box according to the minimum temperature and the maximum temperature includes:

[0023] When the highest temperature is ≥ the first temperature threshold, the cooling mode is turned on, and the cooling mode is turned off when the lowest temperature is < the fourth temperature threshold; wherein the third temperature threshold < the fourth temperature threshold < the upper limit of the optimal charge and discharge temperature range;

[0024] When the first temperature threshold ≤ the maximum temperature < the fifth temperature threshold, cooling and charging the battery box;

[0025] When the fifth temperature threshold ≤ the maximum temperature < the sixth temperature threshold, reducing the charging power of the battery box, and performing power reduction cooling charging on the battery box;

[0026] When the maximum temperature is ≥ the sixth temperature threshold, the charging circuit of the battery box is cut off, the battery box is purely cooled, and the next battery box is switched to perform thermal management; wherein the first temperature threshold < the fifth temperature threshold < the sixth temperature threshold.

[0027] Further, when it is determined that the current working mode of the battery box is the discharge mode, based on the maximum temperature and the minimum temperature, the method for determining and executing a temperature control strategy, a power reduction strategy, and a battery box switching strategy that match the current working mode of the battery box includes:

[0028] When the maximum temperature is less than a first temperature threshold, executing a first discharge temperature control strategy on the battery box according to the minimum temperature and the maximum temperature;

[0029] When the maximum temperature is ≥ the first temperature threshold, a second discharge temperature control strategy, a discharge power reduction strategy and a discharge battery box switching strategy are executed on the battery box according to the minimum temperature and the maximum temperature;

[0030] Among them, the first temperature threshold>the upper limit value of the optimal charging and discharging operating temperature range.

[0031] Further, when the maximum temperature is less than the first temperature threshold, the method for executing the first discharge temperature control strategy on the battery box according to the minimum temperature and the maximum temperature includes:

[0032] When the lowest temperature is ≥ the seventh temperature threshold, the battery box is discharged normally;

[0033] When the lowest temperature is less than the seventh temperature threshold, the heating mode is turned on to heat the battery box purely, and when the highest temperature is greater than or equal to the eighth temperature threshold, the heating mode is turned off to discharge the battery box normally;

[0034] Among them, the eighth temperature threshold is the lowest discharge operating temperature, and the seventh temperature threshold < the eighth temperature threshold < the lower limit of the optimal charge and discharge operating temperature range.

[0035] Further, when the maximum temperature is ≥ the first temperature threshold, the method for executing the second discharge temperature control strategy, the discharge power reduction strategy and the discharge battery box switching strategy on the battery box according to the minimum temperature and the maximum temperature includes:

[0036] When the maximum temperature is ≥ the first temperature threshold, the cooling mode is turned on, and the cooling mode is turned off when the minimum temperature is < the fourth temperature threshold; wherein the lower limit of the optimal charge and discharge operating temperature range < the fourth temperature threshold < the upper limit of the optimal charge and discharge operating temperature range;

[0037] When the first temperature threshold ≤ the highest temperature < the fifth temperature threshold, cooling and discharging the battery box;

[0038] When the fifth temperature threshold ≤ the maximum temperature < the sixth temperature threshold, reducing the discharge power of the battery box, and performing power reduction cooling discharge on the battery box;

[0039] When the maximum temperature is ≥ the sixth temperature threshold, the discharge circuit of the battery box is cut off, the battery box is purely cooled, and the next battery box is switched to perform thermal management; wherein the first temperature threshold < the fifth temperature threshold < the sixth temperature threshold.

[0040] Further, after the step of determining and executing a temperature control strategy, a power reduction strategy, and a battery box switching strategy that match the current working mode of the battery box based on the maximum temperature and the minimum temperature, the method further includes:

[0041] Perform a full thermal runaway inspection on the battery box, and if the battery box has a thermal runaway risk, execute a thermal runaway emergency handling strategy.

[0042] On the other hand, the present application also provides a thermal management system for executing the thermal management method for a battery-swapped ship as described in any one of the aforementioned embodiments, the thermal management system comprising:

[0043] A judging module, used to judge the current working mode of the battery box; wherein the working mode includes a charging mode and a discharging mode;

[0044] An acquisition module, used to acquire the current maximum temperature and minimum temperature of multiple battery cells in the battery box;

[0045] An execution module is used to determine and execute a temperature control strategy, a power reduction strategy and a battery box switching strategy that match the current working mode of the battery box based on the maximum temperature and the minimum temperature.

[0046] Compared with the prior art, this application has the following beneficial effects:

[0047] The present application provides a method and a thermal management system for battery thermal management of battery-exchange ships. The temperature control strategy, power reduction strategy and battery box switching strategy of the battery box in different working modes are all different. By obtaining the current maximum and minimum temperatures of multiple battery cells in the battery box, the current temperature of the battery box can be better monitored. Combined with the temperature control strategy that matches the current working mode of the battery box, it can ensure that the battery operates within the optimal temperature range, thereby improving the thermal management efficiency of the battery. When there is a risk of overheating in the battery box, the risk of overheating can be avoided through the power reduction strategy and the battery box switching strategy, thereby optimizing performance, extending battery life, and improving safety and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians of the art without making creative work are within the scope of protection of the present application.

[0049] Figure 1 A schematic diagram of a thermal management method for a battery-swap ship provided in this application;

[0050] Figure 2 This is one of the sub-step flow charts of step S300 in this application;

[0051] Figure 3 This is the second schematic diagram of the sub-step flow chart of step S300 in this application;

[0052] Figure 4 This is the third schematic diagram of the sub-step flow chart of step S300 in this application;

[0053] Figure 5 This is the fourth schematic diagram of the sub-step flow chart of step S300 in this application;

[0054] Figure 6 A schematic diagram of a thermal management system provided in this application.

[0055] Reference numerals: 400 - thermal management system; 410 - determination module; 420 - acquisition module; 430 - execution module. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0057] In the description of this application, it should be noted that relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium.

[0058] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0059] As mentioned in the background technology, the existing battery thermal management methods have problems such as high battery energy consumption, poor thermal management efficiency, and poor safety, which makes it difficult to meet the thermal management requirements of ship battery cabinets. Therefore, how to improve the thermal management efficiency of batteries and ensure safety and reliability is a technical problem that needs to be solved urgently by those skilled in the art.

[0060] To solve the above technical problems, please refer to Figure 1 The embodiment of the present application provides a battery thermal management method for a battery-swapped ship, which is applied to a thermal management system. The method comprises the following steps:

[0061] Step S100: Determine the current working mode of the battery box, wherein the working mode includes a charging mode and a discharging mode.

[0062] For example, when the battery box is connected to the hull, that is, the battery connector is connected to the hull connector, the thermal management system is started and powered on. At this time, there are two situations:

[0063] If the thermal management system detects the charging wake-up signal CC2, it means that the charging circuit has been connected and charging can be performed, and it is determined that the current working mode of the battery box is the charging mode.

[0064] If the thermal management system does not detect the charging wake-up signal CC2, it is determined that the current operating mode of the battery box is the discharge mode.

[0065] Step S200: obtaining the current maximum temperature and minimum temperature of multiple battery cells in the battery box.

[0066] In the embodiment of the present application, the maximum temperature refers to the highest temperature value recorded at a certain moment by all battery cells or modules in the battery box. This temperature value can reflect the temperature condition of the hottest part of the battery box and is an important indicator for determining whether the battery box has a risk of overheating.

[0067] The minimum temperature refers to the lowest temperature value recorded by all battery cells or modules in the battery box at a certain moment. This temperature value can reflect the temperature condition of the coldest part of the battery box and is an important indicator for determining whether the battery box is working in a low temperature environment.

[0068] Step S300: Based on the maximum temperature and the minimum temperature, determine and execute a temperature control strategy, a power reduction strategy and a battery box switching strategy that match the current working mode of the battery box.

[0069] The current working mode of the battery box is determined by automatically detecting the charging wake-up signal. The temperature control strategy, power reduction strategy and battery box switching strategy of the battery box in different working modes are different. By obtaining the current maximum and minimum temperatures of multiple battery cells in the battery box, the current temperature of the battery box can be better monitored. Combined with the temperature control strategy that matches the current working mode of the battery box, it can ensure that the battery operates within the optimal temperature range, thereby improving the thermal management efficiency of the battery. When there is a risk of overheating in the battery box, the risk of overheating can be avoided through the power reduction strategy and the battery box switching strategy, thereby optimizing performance, extending battery life, and improving safety and reliability.

[0070] Since the control strategies of the battery box in the charging mode and the discharging mode are different, in order to better understand the technical solution of the present application, the control strategy of the battery box in the charging mode is first described below.

[0071] See also Figure 2 As an optional implementation, when it is determined that the current working mode of the battery box is the charging mode, step S300 of determining and executing a temperature control strategy, a power reduction strategy and a battery box switching strategy that match the current working mode of the battery box based on the maximum temperature and the minimum temperature includes sub-steps S311 and S312.

[0072] Step S311: when the maximum temperature is less than the first temperature threshold, a first charging temperature control strategy is executed on the battery box according to the minimum temperature.

[0073] Step S312: When the maximum temperature is ≥ the first temperature threshold, a second charging temperature control strategy, a charging power reduction strategy and a charging battery box switching strategy are executed on the battery box according to the minimum temperature and the maximum temperature.

[0074] It should be noted that in the environment of the optimal charging and discharging temperature range (for example, 15℃~35℃), the charging and discharging capacity of the battery is at a normal level. When the temperature is lower than the lower limit of the optimal charging and discharging temperature range (15℃), the battery's storage capacity will be reduced to 70%~80% of the original. When the temperature drops below -10℃, the storage capacity will be even lower.

[0075] In the embodiment of the present application, the first temperature threshold value is greater than the upper limit of the optimal charge and discharge temperature range. For example, if the optimal charge and discharge temperature range is 15°C to 35°C, the first temperature threshold value may be 38°C.

[0076] Specifically, see Figure 3 , when the battery box is in charging mode, when the maximum temperature T max < the first temperature threshold, it means that the battery box does not have the risk of overheating, but the battery box may be working at a low temperature, resulting in a low charging rate or even failure to charge. Therefore, it is necessary to execute the first charging temperature control strategy for the battery box according to the minimum temperature, that is, step S311 includes sub-steps S3111 and S3112.

[0077] Step S3111: When the minimum temperature T min When the temperature is ≥ the second temperature threshold, the battery box is charged normally.

[0078] The second temperature threshold is the lower limit of the optimal charge and discharge operating temperature range, that is, the second temperature threshold may be 15°C.

[0079] This is equivalent to when the battery box's T min ≥15℃ and T max When the temperature is <38°C, it indicates that the temperature of the battery box is in the optimal charging and discharging temperature range. At this time, the battery box is charged normally.

[0080] Step S3112: When the minimum temperature T min <The second temperature threshold, turn on the heating mode, and charge the battery box according to the charging comparison table until the minimum temperature T min ≥When the temperature reaches the third temperature threshold, the heating mode is turned off and the battery box is charged normally.

[0081] The second temperature threshold < the third temperature threshold < the first temperature threshold. Optionally, the second temperature threshold may be 15°C, the third temperature threshold may be 17°C, and the first temperature threshold may be 38°C.

[0082] This is equivalent to when the battery box's Tmin <15℃ and T max When the temperature is less than 38℃, it means that the battery box is in a low temperature state, resulting in a low charging rate and poor charging effect. At this time, turn on the heating mode and charge the battery box according to the charging comparison table, that is, heat the battery box while charging until the battery box's T min When the temperature is ≥17℃, stop heating and charge the battery box normally.

[0083] It should be noted that the charging reference table in the embodiment of the present application is an external charging MAP table, and the MAP value of the battery charging current generally refers to the maximum allowable charging current. In the battery management system (BMS), the maximum instantaneous current that the battery can safely accept during the charging process is specified. Exceeding this value may cause overheating, damage, or even safety hazards to the battery. Charging the battery box according to the charging reference table can ensure that the charging current is controlled below the MAP value, so as to ensure that the battery can be charged smoothly and safely and extend its service life.

[0084] When the maximum temperature ≥ the first temperature threshold, it indicates that there is a risk of overheating in the battery box. At this time, it is necessary to execute the second charging temperature control strategy, charging power reduction strategy and charging battery box switching strategy on the battery box according to the minimum temperature and the maximum temperature, that is, step S312 includes sub-steps S3121 to S3124.

[0085] Step S3121: When the maximum temperature T max ≥ the first temperature threshold, the cooling mode is turned on until the minimum temperature T min The cooling mode is turned off at the fourth temperature threshold.

[0086] The third temperature threshold < the fourth temperature threshold < the upper limit of the optimal charge and discharge temperature range. Optionally, the third temperature threshold is 17°C, the fourth temperature threshold is 30°C, and the first temperature threshold is 38°C.

[0087] This is equivalent to when T max When the temperature is ≥38℃, it means that the battery box temperature has exceeded the upper limit of the optimal charge and discharge temperature range (35℃). At this time, the battery box needs to be cooled until the battery box T min The cooling mode is turned off when <30℃.

[0088] Since a too high cooling mode startup value will increase the battery safety risk, and a too low cooling mode startup value will increase the cooling energy consumption of the system. In order to solve the above problem, in the embodiment of the present application, the cooling mode startup value (i.e., the first temperature threshold) is slightly larger than the upper limit of the optimal charge and discharge temperature range, which not only improves the safety of battery thermal management but also reduces cooling energy consumption.

[0089] Step S3122: When the first temperature threshold ≤ the maximum temperature T max<When the fifth temperature threshold is reached, the battery box is cooled and charged.

[0090] Step S3123: When the fifth temperature threshold ≤ the maximum temperature T max <When the sixth temperature threshold is reached, the charging power of the battery box is reduced, and the battery box is subjected to reduced-power cooling and charging.

[0091] Step S3124: When the maximum temperature T max When the temperature reaches or exceeds the sixth temperature threshold, the charging circuit of the battery box is cut off, the battery box is cooled purely, and the thermal management is switched to the next battery box.

[0092] The first temperature threshold < the fifth temperature threshold < the sixth temperature threshold. Optionally, the first temperature threshold is 38°C, the fifth temperature threshold is 50°C, and the sixth temperature threshold is 55°C.

[0093] In high temperature environment, the life of the battery will be greatly shortened. If the temperature of the battery exceeds 50℃, the life of the battery will be sharply reduced. In addition, high temperature will also cause the liquid electrolyte inside the battery to evaporate, resulting in a reduction in battery capacity. At the same time, the speed of the chemical reaction inside the battery will also be accelerated under high temperature, making the battery prone to problems such as overcharging and over-discharging, further damaging the battery's service life and causing harm.

[0094] In order to improve the safety of battery thermal management, when 38℃≤T max <50℃, charge the battery box while cooling it. max When the temperature is less than 55℃, the charging power of the battery box is reduced, and the battery box is cooled and charged with reduced power. This effectively reduces the charging current and slows down the temperature rise of the battery box. At the same time, it also leaves sufficient cooling time for the cooling system inside the battery box to further reduce the battery temperature.

[0095] When T max When the temperature is ≥55℃, it is determined that the heat dissipation speed of the battery box is lower than the heat generation speed, and the charging power reduction strategy becomes invalid. At this time, it is necessary to cut off the charging circuit of the battery box and stop charging. The battery cooling system continues to work to keep the battery box in a pure cooling state to prevent thermal runaway and switch to the next battery box for thermal management.

[0096] See below Figure 4 As another optional implementation, when it is determined that the current operating mode of the battery box is the discharge mode, step S300 of determining and executing a temperature control strategy, a power reduction strategy and a battery box switching strategy that match the current operating mode of the battery box based on the maximum temperature and the minimum temperature includes sub-steps S321 and S322.

[0097] Step S321: when the maximum temperature is less than the first temperature threshold, a first discharge temperature control strategy is executed on the battery box according to the minimum temperature and the maximum temperature.

[0098] Step S322: when the maximum temperature is ≥ the first temperature threshold, the second discharge temperature control strategy, the discharge power reduction strategy and the discharge battery box switching strategy are executed on the battery box according to the minimum temperature and the maximum temperature.

[0099] Similarly, the first temperature threshold value is greater than the upper limit of the optimal charge and discharge operating temperature range. Optionally, the optimal charge and discharge operating temperature range is 15°C to 35°C, and the first temperature threshold value is 38°C.

[0100] Specifically, see Figure 5 , when the battery box is in discharge mode, when the maximum temperature T max < the first temperature threshold, it means that the battery box does not have an overheating risk, but the battery box may be operating at a low temperature, resulting in a low discharge rate. Therefore, it is necessary to execute the first discharge temperature control strategy for the battery box according to the minimum temperature and the maximum temperature, that is, step S321 includes sub-steps S3211 and S3212.

[0101] Step S3211: When the minimum temperature T min When the temperature is ≥ the seventh temperature threshold, the battery box is discharged normally.

[0102] Step S3212: When the minimum temperature T min <7th temperature threshold, turn on the heating mode and heat the battery box until the highest temperature T max When the temperature reaches or exceeds the eighth temperature threshold, the heating mode is turned off and the battery box is discharged normally.

[0103] Among them, the eighth temperature threshold is the lowest discharge operating temperature, and the seventh temperature threshold < the eighth temperature threshold < the lower limit of the optimal charge and discharge operating temperature range. Optionally, the seventh temperature threshold is 0°C, the eighth temperature threshold is 4°C, the lower limit of the optimal charge and discharge operating temperature range is 15°C, and the first temperature threshold is 38°C.

[0104] At low temperatures, the discharge capacity and charge capacity of the battery will decrease, and the output power of the battery will also decrease. At low temperatures, the chemical reaction rate inside the battery will slow down, and the battery reaction will be incomplete, causing the battery to easily lose power when the battery is low in power. Therefore, when the battery box T min <0℃ and T max When the temperature is <38℃, turn on the heating mode to heat the battery box purely.

[0105] Since the eighth temperature threshold (ie, 4°C) is the lowest discharge operating temperature of the battery, when the battery box is heated to T maxWhen the temperature is ≥4℃, turn off the heating mode and discharge the battery box normally. During the discharge process, the battery will generate heat due to its own characteristics and gradually heat up to the ideal operating temperature (i.e. 15℃~35℃). This strategy heats the battery to the lowest discharge operating temperature, relies on the battery's own characteristics, ensures the normal operation of the battery, and saves heating energy.

[0106] When the maximum temperature ≥ the first temperature threshold, it indicates that there is a risk of overheating in the battery box. At this time, it is necessary to execute the second discharge temperature control strategy, discharge power reduction strategy and discharge battery box switching strategy for the battery box according to the minimum temperature and the maximum temperature, that is, step S322 includes sub-steps S3221 to S3224.

[0107] Step S3221: When the maximum temperature T max ≥ the first temperature threshold, the cooling mode is turned on until the minimum temperature T min The cooling mode is turned off at the fourth temperature threshold.

[0108] Among them, the lower limit of the optimal charge and discharge operating temperature range < the fourth temperature threshold < the upper limit of the optimal charge and discharge operating temperature range. Optionally, the lower limit of the optimal charge and discharge operating temperature range is 15°C, the fourth temperature threshold is 30°C, the upper limit of the optimal charge and discharge operating temperature range is 35°C, and the first temperature threshold is 38°C.

[0109] This is equivalent to when T max When the temperature is ≥38℃, it means that the battery box temperature has exceeded the upper limit of the optimal charge and discharge temperature range (35℃). At this time, the battery box needs to be cooled and dissipated until the battery box T min The cooling mode is turned off when <30℃.

[0110] Step S3222: When the first temperature threshold ≤ the maximum temperature T max <When the fifth temperature threshold is reached, the battery box is cooled and discharged.

[0111] Step S3223: When the fifth temperature threshold ≤ the maximum temperature T max <When the sixth temperature threshold is reached, the discharge power of the battery box is reduced, and the battery box is subjected to power reduction cooling and discharge.

[0112] Step S3224: When the maximum temperature T max When the temperature reaches or exceeds the sixth temperature threshold, the discharge circuit of the battery box is cut off, the battery box is cooled purely, and the next battery box is switched to perform thermal management.

[0113] The first temperature threshold < the fifth temperature threshold < the sixth temperature threshold. Optionally, the first temperature threshold is 38°C, the fifth temperature threshold is 50°C, and the sixth temperature threshold is 55°C.

[0114] Similarly, in order to improve the safety of battery thermal management and extend the service life of the battery, in the embodiment of the present application, when 38°C ≤ T max <50℃, discharge the battery box while cooling it. max When the temperature is less than 55℃, the discharge power of the battery box is reduced, and the battery box is discharged with reduced power and cooled. This effectively reduces the discharge current and slows down the temperature rise of the battery box. At the same time, it also leaves sufficient cooling time for the cooling system inside the battery box, so that the battery temperature can be further reduced.

[0115] When T max When the temperature is ≥55℃, it is determined that the heat dissipation speed of the battery box is lower than the heat generation speed, and the discharge power reduction strategy becomes invalid. At this time, it is necessary to cut off the discharge circuit of the battery box and stop discharging. The battery cooling system continues to work to keep the battery box in a pure cooling state to prevent thermal runaway and switch to the next battery box for thermal management.

[0116] In the embodiment of the present application, after determining and executing the temperature control strategy, power reduction strategy and battery box switching strategy matching the current working mode of the battery box based on the maximum temperature and the minimum temperature in step S300, the battery thermal management method for battery-swapped ships also includes:

[0117] Conduct thermal runaway inspections on the battery box throughout the entire process, upload data in a timely manner through the BMS and sensors integrated within the thermal management system, formulate a thermal runaway judgment strategy based on the monitoring data of the entire thermal management process, and execute the thermal runaway emergency response strategy if there is a risk of thermal runaway in the battery box.

[0118] For further information, see Figure 6 The embodiment of the present application further provides a thermal management system 400, which is used to execute the thermal management method for a battery-swapped ship as described in any of the above embodiments. The thermal management system 400 includes:

[0119] The determination module 410 is used to determine the current working mode of the battery box, wherein the working mode includes a charging mode and a discharging mode.

[0120] The acquisition module 420 is used to acquire the current maximum temperature and minimum temperature of multiple battery cells in the battery box.

[0121] The execution module 430 is used to determine and execute a temperature control strategy, a power reduction strategy and a battery box switching strategy that match the current working mode of the battery box based on the maximum temperature and the minimum temperature.

[0122] In summary, the embodiments of the present application provide a method for thermal management of batteries for battery-exchange ships and a thermal management system. The current operating mode of the battery box is determined by automatically detecting the charging wake-up signal. The temperature control strategy, power reduction strategy and battery box switching strategy of the battery box in different operating modes are different. By obtaining the current maximum and minimum temperatures of multiple battery cells in the battery box, the current temperature of the battery box can be better monitored. Combined with the temperature control strategy that matches the current operating mode of the battery box, it can ensure that the battery operates within the optimal temperature range, thereby improving the thermal management efficiency of the battery. When there is a risk of overheating in the battery box, the risk of overheating can be avoided through power reduction strategy and battery box switching strategy, thereby optimizing performance, extending battery life, and improving safety and reliability.

[0123] In addition, by conducting thermal runaway inspections on the battery box throughout the process, uploading data in a timely manner through the BMS and sensors integrated in the thermal management system, and formulating a thermal runaway judgment strategy for the monitoring data of the entire thermal management process, it is ensured that when the battery box is detected to have a thermal runaway risk, a thermal runaway emergency response strategy is implemented, which greatly improves the safety and reliability of the battery box in water use and promotes the healthy development of new energy water transportation vehicles. This application not only simplifies the operating process, extends the battery life, and ensures the safe operation of the thermal management system, but also improves energy utilization efficiency, reduces energy consumption and maintenance costs, meets the power management needs of ships of different sizes and needs, and promotes the healthy development of new energy water transportation vehicles.

[0124] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0125] It will be apparent to those skilled in the art that the present application is not limited to the details of the exemplary embodiments described above, and that the present application can be implemented in other specific forms without departing from the spirit or essential features of the present application. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the present application is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present application. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A battery thermal management method for battery swapping ships, characterized in that: Applied to a thermal management system, the method comprises: Determine the current working mode of the battery box; wherein the working mode includes a charging mode and a discharging mode; Obtaining the current maximum temperature and minimum temperature of multiple battery cells in the battery box; Based on the maximum temperature and the minimum temperature, a temperature control strategy, a power reduction strategy, and a battery box switching strategy that match the current operating mode of the battery box are determined and executed.

2. The battery thermal management method for battery replacement ships according to claim 1, characterized in that: Methods for determining the current working mode of the battery box include: If a charging wake-up signal is detected, determining that the current working mode of the battery box is the charging mode; If the charging wake-up signal is not detected, it is determined that the current operating mode of the battery box is the discharging mode.

3. The battery thermal management method for battery replacement ships according to claim 1, characterized in that: In the case where it is determined that the current working mode of the battery box is the charging mode, based on the maximum temperature and the minimum temperature, a method for determining and executing a temperature control strategy, a power reduction strategy, and a battery box switching strategy that match the current working mode of the battery box includes: When the maximum temperature is less than the first temperature threshold, executing a first charging temperature control strategy for the battery box according to the minimum temperature; When the maximum temperature is ≥ the first temperature threshold, executing a second charging temperature control strategy, a charging power reduction strategy and a charging battery box switching strategy on the battery box according to the minimum temperature and the maximum temperature; Among them, the first temperature threshold>the upper limit value of the optimal charging and discharging temperature range.

4. The battery thermal management method for battery replacement ships according to claim 3 is characterized in that: When the maximum temperature is less than the first temperature threshold, the method for executing the first charging temperature control strategy on the battery box according to the minimum temperature includes: When the lowest temperature is ≥ the second temperature threshold, the battery box is charged normally; When the lowest temperature is less than the second temperature threshold, the heating mode is turned on, and the battery box is charged according to the charging comparison table, until the lowest temperature is greater than or equal to the third temperature threshold, the heating mode is turned off, and the battery box is charged normally; The second temperature threshold is the lower limit of the optimal charge and discharge operating temperature range, and the second temperature threshold < the third temperature threshold < the first temperature threshold.

5. The battery thermal management method for battery-exchange ships according to claim 4, characterized in that: When the maximum temperature is ≥ the first temperature threshold, the method for executing the second charging temperature control strategy, the charging power reduction strategy and the charging battery box switching strategy on the battery box according to the minimum temperature and the maximum temperature includes: When the highest temperature is ≥ the first temperature threshold, the cooling mode is turned on, and the cooling mode is turned off when the lowest temperature is < the fourth temperature threshold; wherein the third temperature threshold < the fourth temperature threshold < the upper limit of the optimal charge and discharge temperature range; When the first temperature threshold ≤ the maximum temperature < the fifth temperature threshold, cooling and charging the battery box; When the fifth temperature threshold ≤ the maximum temperature < the sixth temperature threshold, reducing the charging power of the battery box, and performing power reduction cooling charging on the battery box; When the maximum temperature is ≥ the sixth temperature threshold, the charging circuit of the battery box is cut off, the battery box is purely cooled, and the next battery box is switched to perform thermal management; wherein the first temperature threshold < the fifth temperature threshold < the sixth temperature threshold.

6. The battery thermal management method for battery replacement ships according to claim 1, characterized in that: In the case where it is determined that the current working mode of the battery box is the discharge mode, based on the maximum temperature and the minimum temperature, a method for determining and executing a temperature control strategy, a power reduction strategy, and a battery box switching strategy that match the current working mode of the battery box includes: When the maximum temperature is less than a first temperature threshold, executing a first discharge temperature control strategy on the battery box according to the minimum temperature and the maximum temperature; When the maximum temperature is ≥ the first temperature threshold, executing a second discharge temperature control strategy, a discharge power reduction strategy, and a discharge battery box switching strategy on the battery box according to the minimum temperature and the maximum temperature; Among them, the first temperature threshold>the upper limit value of the optimal charging and discharging operating temperature range.

7. The battery thermal management method for battery-exchange ships according to claim 6, characterized in that: When the maximum temperature is less than the first temperature threshold, the method for executing the first discharge temperature control strategy on the battery box according to the minimum temperature and the maximum temperature includes: When the lowest temperature is ≥ the seventh temperature threshold, the battery box is discharged normally; When the lowest temperature is less than the seventh temperature threshold, the heating mode is turned on to heat the battery box purely, and when the highest temperature is greater than or equal to the eighth temperature threshold, the heating mode is turned off to discharge the battery box normally; Among them, the eighth temperature threshold is the lowest discharge operating temperature, and the seventh temperature threshold < the eighth temperature threshold < the lower limit of the optimal charge and discharge operating temperature range.

8. The battery thermal management method for battery-exchange ships according to claim 7, characterized in that: When the maximum temperature is ≥ the first temperature threshold, the method for executing the second discharge temperature control strategy, the discharge power reduction strategy and the discharge battery box switching strategy on the battery box according to the minimum temperature and the maximum temperature includes: When the maximum temperature is ≥ the first temperature threshold, the cooling mode is turned on, and the cooling mode is turned off when the minimum temperature is < the fourth temperature threshold; wherein the lower limit of the optimal charge and discharge operating temperature range < the fourth temperature threshold < the upper limit of the optimal charge and discharge operating temperature range; When the first temperature threshold ≤ the highest temperature < the fifth temperature threshold, cooling and discharging the battery box; When the fifth temperature threshold ≤ the maximum temperature < the sixth temperature threshold, reducing the discharge power of the battery box, and performing power reduction cooling discharge on the battery box; When the maximum temperature is ≥ the sixth temperature threshold, the discharge circuit of the battery box is cut off, the battery box is purely cooled, and the next battery box is switched to perform thermal management; wherein the first temperature threshold < the fifth temperature threshold < the sixth temperature threshold.

9. The battery thermal management method for battery-exchange ships according to claim 1, characterized in that: After the step of determining and executing a temperature control strategy, a power reduction strategy, and a battery box switching strategy that match the current working mode of the battery box based on the maximum temperature and the minimum temperature, the method further includes: Perform a full thermal runaway inspection on the battery box, and if the battery box has a thermal runaway risk, execute a thermal runaway emergency handling strategy.

10. A thermal management system, characterized in that: Used to execute the battery thermal management method for battery-exchange ships according to any one of claims 1 to 9, the thermal management system comprising: A judgment module, used to judge the current working mode of the battery box; wherein the working mode includes a charging mode and a discharging mode; An acquisition module, used to acquire the current maximum temperature and minimum temperature of multiple battery cells in the battery box; An execution module is used to determine and execute a temperature control strategy, a power reduction strategy and a battery box switching strategy that match the current working mode of the battery box based on the maximum temperature and the minimum temperature.

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