Battery box control method and device, electronic equipment and vehicle

Abstract

The invention provides a control method and device of a battery box, electronic equipment and a vehicle, and relates to the technical field of storage batteries. The control method comprises the steps that the temperature value of a battery box is obtained, the battery box comprises a first type of battery pack and a second type of battery pack, and the first type of battery pack and the second type of battery pack are different in battery type; and when the temperature value is between the second temperature threshold value and the first temperature threshold value, controlling the first type of battery packs and the second type of battery packs to charge and discharge mutually so as to heat the battery box. The battery box formed by the first type of battery packs and the second type of battery packs can guarantee energy density and safety, and heat dissipated by mutual charging and discharging keeps own use temperature, so that the battery box can be safely used under the condition that the external temperature does not meet the use temperature of the battery box, the time for a user to wait for heating is saved, and the user experience is improved. And the transportation efficiency of users is improved.

Description

Technical Field

[0001] The present application relates to the technical field of storage batteries, and particularly to a control method, a control device, an electronic device and a vehicle for a battery box. Background Art

[0002] With the development of the new energy industry, more and more vehicles are starting to use lithium batteries as power sources. Especially recently, the electric heavy truck industry has made rapid progress. Since the current commercial vehicle battery system has been using the electric bus electrical architecture, considering factors such as battery safety and economy, the system battery cells are generally mainly lithium iron phosphate. However, in the face of the increasing demand for vehicle driving range, the energy density of lithium iron phosphate is relatively low, and it is difficult to significantly improve the vehicle driving range. In addition, lithium iron phosphate batteries perform poorly in winter, especially during charging. Users need to spend a lot of time waiting for the battery to heat up, and can only charge after the temperature meets certain conditions, which seriously affects the transportation efficiency at the user end.

[0003] To solve this problem, at present, ternary lithium batteries are tried to replace lithium iron phosphate batteries, so as to improve the driving range of commercial vehicles. At the same time, ternary lithium performs well at low temperatures and can generally be used normally in winter. Since the energy density of ternary lithium batteries is relatively high, their safety is not as good as that of lithium iron phosphate. If the entire battery system is switched to ternary lithium, once a thermal runaway occurs in such a large-capacity battery system, it will cause huge losses.

[0004] Therefore, there is an urgent need to provide a control method, a control device, an electronic device, a readable storage medium and a vehicle for a battery box, so that the battery box can meet the requirements of energy density, can be used in a low-temperature environment, and can also ensure safety. Summary of the Invention

[0005] The present application provides a control method, a control device, an electronic device, a readable storage medium and a vehicle for a battery box, so that it can meet the requirements of energy density, can be used in a low-temperature environment, and can ensure safety.

[0006] In a first aspect, the present application provides a control method for a battery box. The control method includes: obtaining a temperature value of the battery box, where the battery box includes a first type of battery pack and a second type of battery pack, and the battery types of the first type of battery pack and the second type of battery pack are different; when the temperature value is between a second temperature threshold and a first temperature threshold, controlling the first type of battery pack and the second type of battery pack to charge and discharge with each other to heat the battery box; where the second temperature threshold is the minimum of the minimum rechargeable temperature value of the first type of battery pack and the minimum rechargeable temperature value of the second type of battery; the first temperature threshold is greater than or equal to the maximum of the minimum rechargeable temperature value of the first type of battery pack and the minimum rechargeable temperature value of the second type of battery.

[0007] Through the above solution, the battery box includes a first type of battery pack and a second type of battery pack. Combining these two types of battery packs with different battery types can enable the battery box to achieve complementary advantages in terms of energy storage and power output, meeting both the device's requirement for a longer battery life and its ability to handle sudden high-power demands, enhancing the overall performance of the entire battery system and avoiding the unsafe factors when using a single high-energy-density battery. Different types of batteries have different minimum rechargeable temperature values, which are key parameters to ensure that the battery can be charged safely and effectively in a low-temperature environment. To avoid the situation where neither the first type of battery pack nor the second type of battery pack can be charged when the temperature is extremely low, a first temperature threshold and a second temperature threshold are set, and these two thresholds are determined based on the minimum rechargeable temperature values of the two types of battery packs, enabling the precise determination of the lowest temperature range at which the battery box can be mutually charged. The second temperature threshold is the minimum value among the minimum rechargeable temperature values of the two types of batteries. When the temperature is greater than the second temperature threshold and less than the first temperature threshold, the first type of battery pack and the second type of battery pack can self-heat through the heat generated by mutual charging and discharging, so that the temperature value of the battery box can be used even when the external temperature does not meet the operating temperature of the battery box, saving the user's waiting time for heating and improving the user's transportation efficiency.

[0008] In a possible design, when the temperature value is between the second temperature threshold and the first temperature threshold, controlling the mutual charging and discharging between the first type of battery pack and the second type of battery pack includes: when the temperature value is greater than a third temperature threshold and less than the first temperature threshold, controlling the mutual charging and discharging between the first type of battery pack and the second type of battery pack, where the third temperature threshold is equal to the minimum rechargeable temperature value of the first type of battery pack, and the minimum rechargeable temperature value of the first type of battery pack is the maximum value.

[0009] With the above solution, when the temperature value is within a specific range (between the second temperature threshold and the first temperature threshold), by introducing a third temperature threshold, the temperature control strategy is further refined. This segmented control method can more precisely manage the charging and discharging process of the battery pack, ensuring the safe operation of the battery system under different temperature conditions. By setting the third temperature threshold, the system can flexibly adjust the charging and discharging strategy according to different temperature ranges. This design not only enhances the adaptability of the system but also better copes with complex and changing environmental conditions. When the temperature is between the third temperature threshold and the first temperature threshold, that is, at this temperature, both types of battery packs can be charged or discharged. Therefore, when the temperature is between the third temperature threshold and the first temperature threshold, they can charge and discharge each other to increase the temperature of the battery box, so that the battery box works within an appropriate temperature range, thereby improving the working efficiency. By optimizing the charging and discharging control strategy, the system can maintain efficient operation within a wider temperature range. This design not only improves the overall efficiency of the battery system but also extends the service life of the battery.

[0010] In a possible design, when the temperature value is between the second temperature threshold and the first temperature threshold, controlling the charging and discharging between the first type of battery pack and the second type of battery pack further includes: when the temperature value is greater than the second temperature threshold and less than the third temperature threshold, controlling the first type of battery pack to charge the second type of battery pack.

[0011] With the above solution, since the third temperature threshold is equal to the minimum rechargeable temperature value of the first type of battery pack, when the temperature is less than the third temperature threshold, the first type of battery pack cannot be charged (only discharged). Therefore, when the temperature value is greater than the second temperature threshold and less than the third temperature threshold, controlling the first type of battery pack to discharge can effectively avoid charging the first type of battery pack at too low a temperature, reduce the damage to the internal chemical reactions and material structures of the battery at low temperature, and extend the battery life of the first type of battery pack.

[0012] In a possible design, when the temperature value is between the second temperature threshold and the first temperature threshold, controlling the charging and discharging between the first type of battery pack and the second type of battery pack includes: when the temperature value is between the second temperature threshold and the first temperature threshold and the total power value of the battery box is greater than or equal to the first power threshold, controlling the charging and discharging between the first type of battery pack and the second type of battery pack, where the total power value is the sum of the power values of the first type of battery pack and the second type of battery pack, and the first power threshold is the minimum dischargeable power value of the battery box.

[0013] Through the above solution, when the temperature value is between the second temperature threshold and the first temperature threshold, the charge and discharge control is further combined with the total power value of the battery box. This design not only considers the temperature factor but also introduces the power condition, making the charge and discharge process more accurate and safe. When the total power value of the battery box is greater than or equal to the first power threshold, the first type of battery pack and the second type of battery pack are allowed to charge and discharge each other. When the total power value is lower than the first power threshold, the mutual charge and discharge between the two types of battery packs is stopped, which can effectively avoid the safety problems caused by over-discharge of the battery. Over-discharge will cause the internal voltage of the battery to be too low, which may cause the internal chemical reaction of the battery to be unbalanced, and even lead to battery damage or safety risks. This design ensures that when the battery system conducts energy interaction, there is enough power reserve to avoid system failures or performance degradation caused by insufficient power. By introducing a control strategy with dual conditions of temperature and power, the charge and discharge management of the battery system under complex working conditions is optimized. This strategy not only improves the safety, reliability and energy utilization efficiency of the system, but also extends the battery life, enhances the adaptability of the system, and significantly improves the user experience.

[0014] In a possible design, when the temperature value is between the second temperature threshold and the first temperature threshold, controlling the first type of battery pack and the second type of battery pack to charge and discharge each other further includes: obtaining the first power value of the first type of battery pack and the second power value of the second type of battery pack; when the temperature value is between the second temperature threshold and the first temperature threshold, and both the first power value and the second power value are between the second power threshold and the third power threshold, controlling the first type of battery pack and the second type of battery pack to charge and discharge each other, where the second power threshold is determined according to the minimum dischargeable power value of the first type of battery pack or the minimum dischargeable power value of the second type of battery pack; the third power threshold is determined according to the maximum chargeable power value of the first type of battery pack or the maximum chargeable power value of the second type of battery pack.

[0015] Through the above solution, the first type of battery pack and the second type of battery pack are charged and discharged between the minimum dischargeable power value and the maximum chargeable power value, which can ensure that the battery pack will not enter the over-discharge state due to too low power during the charge and discharge process, thus avoiding permanent damage to the battery performance. It also prevents the battery pack from overcharging due to over-full power, avoiding safety hazards such as battery swelling, heating and even fire caused by overcharging.

[0016] In a possible design, the control method further includes: detecting the temperature value of the battery box; when the temperature value is greater than or equal to the eighth temperature threshold and less than the first temperature threshold, heating the battery box by an external temperature control method to make the temperature value of the battery box higher than the first temperature threshold, where the eighth temperature threshold is less than or equal to the first temperature threshold; or, detecting the temperature value of the battery box; when the temperature value is greater than or equal to the fourth temperature threshold, cooling the battery box by an external temperature control method to make the temperature of the battery box lower than the fourth temperature threshold; the fourth temperature threshold is determined according to the maximum operating temperature of the battery box.

[0017] Through the above solution, when the temperature is lower than the first temperature threshold and higher than the eighth temperature threshold, the external heating method is used to raise the temperature above the first temperature threshold, ensuring that the battery pack can be safely started and operated in a low-temperature environment. When the temperature is higher than the fourth temperature threshold, the external cooling method is used to prevent the battery box from overheating due to excessive temperature, avoiding the degradation of battery performance or potential safety hazards caused by high temperature. By strictly controlling the temperature range of the battery box, the battery pack is prevented from operating at extreme temperatures. This design reduces the performance degradation of the battery caused by high or low temperatures, thereby extending the service life of the battery. The use of the external temperature control method is only activated when necessary, avoiding unnecessary heating or cooling operations. This strategy not only improves the energy utilization efficiency but also reduces the overall energy consumption of the system. This design further optimizes the temperature control strategy of the battery box by introducing an external temperature control method and combining it with fine temperature threshold management. It not only improves the safety, reliability, and energy utilization efficiency of the system but also extends the service life of the battery, enhances the adaptability of the system, and significantly improves the user experience. This strategy is particularly suitable for battery management systems that require high safety and high efficiency, ensuring the stable operation of the battery system under complex environmental conditions.

[0018] In a possible design, the control method further includes: when the temperature value is greater than the first temperature threshold and less than or equal to the fourth temperature threshold, entering the power-on mode.

[0019] Through the above solution, by setting the first temperature threshold and the fourth temperature threshold, the system enters the power-on mode only when the temperature is within the safe range. This avoids starting the battery at too low or too high a temperature, thereby reducing potential safety hazards caused by abnormal temperature. This strategy can effectively prevent failures caused by the temperature exceeding the safe operating range of the battery, such as battery overheating, short circuit, or performance degradation at low temperatures.

[0020] In a possible design, the control method further includes: when the temperature value is between the first temperature threshold and the fifth temperature threshold, controlling the first type of battery pack and the second type of battery pack to charge and discharge each other so that the temperature value is within a first preset temperature range, where the first preset temperature range is between a sixth temperature threshold and a seventh temperature threshold, the sixth temperature threshold is greater than the fifth temperature threshold, and the seventh temperature threshold is less than the fourth temperature threshold.

[0021] Through the above solution, when the temperature value is between the first temperature threshold and the fifth temperature threshold, by controlling the charge and discharge between the first type of battery pack and the second type of battery pack, the temperature value is maintained within the first preset temperature range (between the sixth temperature threshold and the seventh temperature threshold). This design realizes the dynamic adjustment of temperature through the energy interaction between the battery packs, avoiding large fluctuations in temperature. Through the charge and discharge between the battery packs, the system can dynamically adjust the temperature to ensure that the battery packs operate within the optimal working temperature range. This strategy not only improves the overall performance of the system but also enhances the energy output efficiency of the battery packs.

[0022] In a possible design, the first type of battery pack is a lithium iron phosphate battery, and the second type of battery pack is a ternary lithium system battery.

[0023] Through the above solution, the lithium iron phosphate battery has high safety, and the ternary lithium system battery has a large energy density. By combining the characteristics of the lithium iron phosphate battery and the ternary lithium system battery, and adopting a suitable charge and discharge control strategy, the performance and safety of the battery box can be effectively optimized, which is applicable to a variety of actual application scenarios.

[0024] In a second aspect, the present application provides a control device for a battery box system, including: an acquisition module for acquiring the temperature value of the battery box, where the battery box includes a first type of battery pack and a second type of battery pack, and the battery types of the first type of battery pack and the second type of battery pack are different; a first control module for controlling the first type of battery pack and the second type of battery pack to charge and discharge each other to heat the battery box when the temperature value is between the second temperature threshold and the first temperature threshold; where the second temperature threshold is the minimum of the minimum rechargeable temperature values of the first type of battery pack and the second type of battery, and the first temperature threshold is greater than or equal to the maximum of the minimum rechargeable temperature values of the first type of battery pack and the second type of battery.

[0025] In a third aspect, the present application provides an electronic device, including: a processor, a communication interface, a memory, and a communication bus, where the processor, the communication interface, and the memory communicate with each other through the communication bus; a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of any one of the above control methods.

[0026] Fourthly, the present application provides a computer-readable storage medium storing a computer program executable by an electronic device. When the computer program runs on the electronic device, the electronic device is caused to execute the steps of any one of the above control methods.

[0027] Fifthly, the present application provides a vehicle, specifically including: an electronic device for implementing any one of the above control methods; a processor that runs a program, and when the program runs, executes the steps of any one of the above control methods on the data output from the electronic device; a storage medium for storing the program, and when the program runs, executes the steps of any one of the above control methods on the data output from the electronic device.

[0028] For what is provided in the second aspect above and each possible design of the second aspect, the beneficial effects can refer to the beneficial effects brought by the first aspect above and each possible implementation manner of the first aspect, which will not be elaborated here.

[0029] The above description is only an overview of the technical solutions of the embodiments of the present application. In order to be able to understand the technical means of the embodiments of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of the embodiments of the present application more obvious and understandable, the following specifically gives the specific implementation manners of the present application. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for description in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained according to these drawings without creative efforts.

[0031] Figure 1 Schematic structural diagram of a battery box system provided by an embodiment of the present application.

[0032] Figure 2 Schematic structural diagram of setting an inverter in a battery box system provided by an embodiment of the present application.

[0033] Figure 3 Schematic waterway layout diagram of a battery box system provided by an embodiment of the present application.

[0034] Figure 4 Schematic fire protection layout diagram of a battery box system provided by an embodiment of the present application.

[0035] Figure 5 Schematic electrical architecture diagram of a battery box system provided by an embodiment of the present application.

[0036] Figure 6Schematic diagram of the high-voltage box of the battery box system provided by an embodiment of the present application.

[0037] Figure 7 Flowchart of the control method of the battery box provided by an embodiment of the present application.

[0038] Figure 8 Partial flowchart of the control method of the battery box provided by an embodiment of the present application.

[0039] Figure 9 Partial flowchart of the control method of the battery box provided by an embodiment of the present application.

[0040] Figure 10 Partial flowchart of the control method of the battery box provided by an embodiment of the present application.

[0041] Figure 11 Partial flowchart of the control method of the battery box provided by an embodiment of the present application.

[0042] Figure 12 Partial flowchart of the control method of the battery box provided by an embodiment of the present application.

[0043] Figure 13 Partial flowchart of the control method of the battery box provided by an embodiment of the present application.

[0044] Figure 14 Partial flowchart of the control method of the battery box provided by an embodiment of the present application.

[0045] Figure 15 Power-on flowchart of the battery box provided by an embodiment of the present application.

[0046] Figure 16 Flowchart of the towed mode of the battery box provided by an embodiment of the present application.

[0047] Figure 17 Flowchart of heating and regulating the temperature of the battery box by the external temperature control method provided by an embodiment of the present application.

[0048] Figure 18 Flowchart of cooling and regulating the temperature of the battery box by the external temperature control method provided by an embodiment of the present application.

[0049] Figure 19 Control flowchart of standby heat preservation provided by an embodiment of the present application.

[0050] Figure 20 Schematic diagram of the control device of a battery box system provided by an embodiment of the present application. Detailed implementation manners

[0051] To make the objectives, technical solutions and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Apparently, the described embodiments are some but not all of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of this application without making creative efforts shall fall within the scope of protection of this application.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used in the description of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the description and claims of this application and the accompanying drawings are intended to cover non-exclusive inclusion.

[0053] Reference to "embodiment" herein means that a particular feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of this application. The phrase "embodiment" appearing in various places in the description is not necessarily referring to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0054] The term "and / or" herein is merely a description of the associated relationship of the associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: the existence of A, the simultaneous existence of A and B, and the existence of B. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0055] The orientation terms appearing in the following description are all the directions shown in the figures and do not limit the specific structure of this application. For example, in the description of this application, terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to this application.

[0056] In addition, terms such as "first", "second", etc. in the description and claims of this application or the above-mentioned drawings are used to distinguish different objects and are not used to describe a specific order, and may explicitly or implicitly include one or more of such features.

[0057] In the description of the present application, unless otherwise specified, "plural" means two or more (including two). Similarly, "multiple groups" means two or more groups (including two groups).

[0058] In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection", and "linkage" should be understood in a broad sense. For example, the "connection" or "linkage" of a mechanical structure may refer to a physical connection. For example, a physical connection may be a fixed connection, such as a fixed connection through a spacer, such as a fixed connection through screws, bolts, or other spacers; a physical connection may also be a detachable connection, such as a snap connection or a snap-fit connection; a physical connection may also be an integral connection, such as a connection formed by welding, bonding, or integral molding. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances. The "connection" or "linkage" of a circuit structure may refer to not only a physical connection but also an electrical connection or a signal connection. For example, it may be a direct connection, that is, a physical connection, or it may be indirectly connected through at least one intermediate component, as long as the circuit is connected. It may also be the internal connection of two components; in addition to a signal connection through a circuit, a signal connection may also refer to a signal connection through a media medium, such as radio waves. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0059] The Vehicle Control Unit (VCU) is a key component in an electric vehicle or a hybrid vehicle, responsible for the power control of the whole vehicle and the coordination of various functions.

[0060] The Battery Management System (BMS for short) is a system used to monitor and manage battery cells.

[0061] The Battery Management Unit (BMU for short) is a key component in the battery management system, responsible for monitoring and managing the state of the corresponding battery pack to ensure the safe, efficient, and stable operation of the battery.

[0062] The Thermal Management System (TMS) is the core component in the automated control system of a water-cooled air-conditioning unit. Its main function is to control and adjust the temperature of each component to ensure that they operate in the optimal temperature range, thereby ensuring the safety and performance of the system.

[0063] Fire Fighting System (FFS), which can be used to achieve the single - box fire - fighting and extinguishing function.

[0064] A DC / DC converter, also known as a DC - to - DC converter, is a power - electronic device that converts one DC voltage into another or multiple DC voltages. For example, it converts high - voltage DC into low - voltage DC to meet the requirements of the subsequent circuit.

[0065] Currently, the battery systems of commercial vehicles on the market generally use lithium iron phosphate batteries. However, lithium iron phosphate performs poorly under low - temperature conditions, especially when the temperature is below 0°C, it cannot be charged. Therefore, when charging is required below 0°C, the battery system needs to be heated. After the temperature reaches a certain condition, it can be charged. During the heating process, the power of the battery - box system itself is consumed, which will have a greater impact on the battery's cruising range.

[0066] In related technologies, attempts have been made to replace lithium iron phosphate batteries with ternary lithium batteries to improve the cruising range of commercial vehicles. At the same time, ternary lithium batteries perform well at low temperatures and can generally be used normally in winter. However, ternary lithium batteries have a higher energy density and lower safety than lithium iron phosphate. If the entire battery system is switched to ternary lithium batteries, once a thermal runaway occurs in such a large - capacity battery system, it will cause huge losses.

[0067] Therefore, a control method, control device, electronic device, readable storage medium, and vehicle for a battery box are needed to ensure safety while meeting the requirements of energy density and being able to charge in a low - temperature environment.

[0068] Figure 1 Schematic diagram of the battery - box system provided in this embodiment. Please refer to Figure 1 In this embodiment, a battery - box system is provided, including: a water - cooling unit control unit, a first - type battery pack, a second - type battery pack, and a battery management system; the first - type battery pack includes at least one first battery module, and each first battery module is connected in series; the second - type battery pack includes at least one second battery module, and each second battery module is connected in series; the battery types of the first battery module and the second battery module are different, the first - type battery pack and the second - type battery pack are connected in parallel, and both the first - type battery pack and the second - type battery pack are connected to the battery management system and the water - cooling unit control unit.

[0069] The battery box system includes a first type of battery pack and a second type of battery pack, and each battery pack is formed by connecting multiple battery modules in series. The difference in battery types between the first battery module and the second battery module can refer to different voltages, capacities, energy densities, or chemical compositions of the first battery module and the second battery module. This diversity can provide a wider range of applications and higher flexibility. This design allows the system to flexibly configure different types or different performance batteries according to needs to adapt to different application scenarios. The first type of battery pack and the second type of battery pack are connected in parallel, so that the total current can be increased while the voltage remains the same, improving the output capacity of the battery box system. The battery box system includes a battery management system for monitoring and managing the states of the two groups of batteries, including real-time monitoring of parameters such as voltage, current, and temperature, as well as safety management of the battery charging and discharging processes. It also includes a water-cooling unit control unit for managing the thermal management of the batteries to ensure that the batteries operate at an appropriate temperature, improving battery performance and lifespan. Since the battery box system has a first type of battery pack and a second type of battery pack with different types, the charging and discharging between these two different types of batteries can be utilized to achieve the function of automatic heating. This design solves the problem that the batteries need to be preheated for a long time in a low-temperature environment, improving the battery usage efficiency and transportation efficiency. The automatic heating function reduces the time waiting for the batteries to heat up, enabling the batteries to be quickly charged at a lower temperature, thus significantly improving the transportation efficiency at the user end. At the same time, the combination of the first battery module and the second battery module has complementary energy characteristics. For example, one group may be more suitable for high-power output, while the other group may be more suitable for high energy density, thereby optimizing the overall performance and ensuring safety. Different types of batteries can be selected and equipped according to the energy of the batteries, and then the BMS monitors and manages the batteries, further ensuring the safety of the battery box system during use. In summary, the design of this battery box system not only improves the battery usage efficiency and transportation efficiency through its innovative structure and functions, but also ensures the safe and stable operation of the batteries through the BMS and the water-cooling unit control unit.

[0070] In this embodiment, each first battery module or second battery module is correspondingly provided with a slave battery control unit, and the slave battery control unit is used to monitor the battery state of the first battery module or the second battery module.

[0071] In this embodiment, the first battery module is a lithium iron phosphate battery, the second battery module is a ternary lithium system battery, and the number of the first battery cells is three-fifths of that of the second battery cells.

[0072] Lithium iron phosphate battery (LFP) has a long lifespan, good thermal stability, and cost-effectiveness, and is usually used in applications that require high safety and long lifespan.

[0073] Ternary lithium batteries have a high energy density and can store more energy in the same volume or weight, making them suitable for applications that require high power and energy density. Depending on the cathode material, ternary lithium batteries can be NMC (nickel, manganese, and cobalt) or NCA (nickel, cobalt, and aluminum).

[0074] Lithium iron phosphate batteries have good thermal stability, which may simplify the design of the thermal management system. Ternary lithium batteries, due to their high energy, require more stringent temperature control. Therefore, in this embodiment, the number of battery cells in the first battery pack is three-fifths of that in the second battery pack. This ratio may balance the voltage and energy density of the two battery systems to achieve the best performance of the system design. Moreover, by combining lithium iron phosphate batteries with lower costs and ternary lithium batteries with higher energy density, a balance can be found between cost and performance.

[0075] It can be understood that generally, for battery boxes of the same volume, the energy density of ternary lithium batteries is 1.33 times that of lithium iron phosphate batteries. In this embodiment, to balance the power of the two branches of the first type of battery pack and the second type of battery pack, and also considering safety, the energy proportion of ternary lithium batteries is controlled below 50%. Therefore, Figure 1 in the branch of the first type of battery pack, 5 identical first battery packs are connected in series ( Figure 1 and Figure 2 the battery boxes 1 to 5 in Figure 1 and Figure 2 ), while in the branch of the second type of battery pack, 3 identical second battery packs are connected in series ( Figure 1 and Figure 2 the battery boxes 6 to 8 in Figure 1 and Figure 2 ). The entire battery system has a total of 8 battery packs. If the power of a single lithium iron phosphate battery box is defined as nkwh, the power of the entire battery system is approximately 9nkwh. Compared with 8 pure lithium iron phosphate battery boxes, the energy improvement ratio of the entire system exceeds 10%.

[0076] Reference can be made to Figure 1 , in this embodiment, the entire battery box system can be arranged according to the common back-mounted 6-layer battery rack for commercial vehicles. Considering that the safety of ternary lithium batteries is not as stable as that of lithium iron phosphate batteries, we adopt a diagonal arrangement scheme during the layout of ternary lithium battery boxes (that is, the adjacent upper and lower layers of battery boxes are diagonally distributed, as shown in the positions of battery boxes 6, 7, and 8 in the figure). The advantage of this arrangement scheme is that it can increase the spacing between ternary lithium battery boxes, thereby reducing the risk of thermal spread to surrounding ternary lithium battery boxes after a single box experiences thermal runaway.

[0077] Due to the voltage differences between different types of battery packs, to better ensure the voltage consistency between the two branches and reduce the circulating current in the circuit, an inverter can be added at the end of each branch. After voltage conversion by the inverter, it is then merged into the high-voltage box. Figure 2This is a schematic structural diagram of the battery box system provided in this embodiment. Please refer to Figure 2 In this embodiment, the battery box system further includes: a first inverter and a second inverter. The first type of battery pack is connected in parallel with the first inverter, and the first inverter is connected to the battery management system; the second type of battery pack is connected in parallel with the second inverter, and the second inverter is connected to the battery management system.

[0078] Figure 3 This is a schematic diagram of the water circuit layout structure of the battery box system provided in an embodiment of the present application. As Figure 3 shown, the water-cooled unit control unit includes a water-cooled unit, a first solenoid valve, and a second solenoid valve. The first solenoid valve is connected between each first battery pack and the water-cooled unit, and the second solenoid valve is connected between each second battery pack and the water-cooled unit. The first solenoid valve and the second solenoid valve are connected in parallel with each other.

[0079] In this embodiment, the first type of battery pack and the second type of battery pack share a water-cooled unit in a parallel manner. An additional solenoid valve is added to each of the outlet branches of the water-cooled unit, which can more conveniently control the water circuits of the first type of battery pack and the second type of battery pack respectively. In this way, according to the requirements of system control, the corresponding solenoid valve can be opened or closed, so as to achieve the cooling control effect on the first type of battery pack and the second type of battery pack respectively. In this embodiment, the battery packs in the same type of battery pack branch are connected in parallel, which can better adjust the flow rate of each battery pack.

[0080] In some embodiments, a gasket can also be added to the inlet connector of each battery pack, and by controlling the area of the gasket, the flow rate in each battery pack can be made consistent.

[0081] In this embodiment, a fire control unit is further included. The battery management system is connected to the fire control unit. Among them, the fire control unit includes a fire host, a first puncture valve, and a second puncture valve. Each first battery pack is connected to the first puncture valve, and each second battery pack is connected to the second puncture valve; the first puncture valve and the second puncture valve are connected to the fire host through a three-way valve.

[0082] Figure 4 This is a schematic diagram of the fire layout structure of the battery box system provided in this embodiment. Please refer to Figure 3 and Figure 4, the battery box system also includes: a vehicle control unit, and the battery management system is connected to the vehicle control unit. The VCU can coordinate the energy management of the whole vehicle according to the information provided by the BMS, such as the remaining battery charge (SOC), battery health state (SOH), voltage, temperature, etc. It can adjust the vehicle performance according to the battery state, for example, limit the power output to protect the battery or extend the driving range. It can receive the alarm signals from the BMS, such as overcharge, over-discharge, overheat, etc., and take timely measures to ensure the safety of the vehicle and passengers. Through the connection between the BMS and the VCU, the battery box system can not only effectively manage the battery, but also cooperate with other control systems of the whole vehicle, improve the performance and safety of the whole vehicle, and optimize the energy utilization efficiency at the same time.

[0083] such as Figure 4 shown, in order to ensure the fire safety of the system, a fire control unit is provided in the battery box system. As Figure 4 can be seen, the entire fire control unit consists of a fire host, a fire main pipeline, branch pipelines, puncture valve assemblies, etc. The fire host can judge whether to trigger fire protection according to the signals detected by the detection modules in each battery box. Once the corresponding sensing signal is detected, the fire host will open the puncture valve of this branch, and the internal fire extinguishing medium will be pumped into the corresponding battery box through the delivery pump, so as to realize the single-box fire extinguishing function. At the same time, the fire host will send the fire alarm signal to the alarm module and the BMS, and the BMS will then send this information to the VCU, and finally display the danger information on the cab instrument panel, so as to realize the warning function for the drivers and passengers.

[0084] Figure 5 is the electrical architecture schematic diagram of the battery box system provided in this embodiment. Please refer to Figure 5 , the control unit of the entire battery box system is the BMS. The BMU (battery box slave control unit), TMS (water-cooled unit control unit), FFS (fire control unit), and DC / DC (converter) inside its system communicate with the BMS. Especially, the DC / DC module will adjust the output current of each branch pipeline in real time according to the power issued by the BMS. Through this electrical architecture, the advantages of ternary lithium with high rate can be fully exerted. Especially under the condition of large rate in a short time, the BMS will let the ternary lithium bear most of the power, so that the system will not generate a high temperature rise, which will greatly improve the service life of the system.

[0085] In this embodiment, a charging device is also included. The first type of battery pack and the second type of battery pack are respectively connected to the output end of the charging device, and the positive and negative poles of the water-cooled unit are respectively connected in parallel with the charging device.

[0086] Figure 6 is the electrical schematic diagram of the high-voltage box of the battery box system provided in this embodiment. Please refer to Figure 6, in this embodiment, relays corresponding to the first type of battery pack and the second type of battery pack are respectively connected in series in the input branch, which can be called the first branch relay and the second branch relay. Such a design can not only control the opening and closing of the first type of battery pack and the second type of battery pack more flexibly, but also when the battery box system needs to be powered and heated by an external charging device, since the positive and negative poles of the water-cooled unit are respectively connected in parallel with the charging device, that is, the positive and negative poles of the water-cooled unit are respectively connected to the positive main road and the negative main road, there will be a voltage on the main road at this time, and the existence of the voltage will charge the battery pack at the input end.

[0087] Figure 7 is the flowchart of the control method for the battery box provided in this embodiment. Please refer to Figure 7 , in this embodiment, a control method for a battery box is provided, and the control method includes:

[0088] Step 1, obtain the temperature value of the battery box, where the battery box includes a first type of battery pack and a second type of battery pack, and the battery types of the first type of battery pack and the second type of battery pack are different.

[0089] The battery box includes a first type of battery pack and a second type of battery pack. These two types of battery packs with different battery types are combined together, which can make the battery box achieve complementary advantages in terms of energy storage and power output, not only meeting the equipment's requirements for a longer endurance time, but also being able to cope with sudden high-power demands, improving the comprehensive performance of the entire battery system, and avoiding unsafe factors when using a single high-energy-density battery. Different types of batteries have different minimum rechargeable temperature values, and these values are key parameters to ensure that the battery can be charged safely and effectively in a low-temperature environment.

[0090] In this embodiment, the battery packs in the first type of battery pack can be lithium iron phosphate batteries, and the battery packs in the second type of battery pack can be ternary lithium system batteries. Lithium iron phosphate batteries have high safety, and ternary lithium system batteries have a large energy density. By combining the characteristics of lithium iron phosphate batteries and ternary lithium system batteries, and adopting appropriate charge and discharge control strategies, the performance and safety of the battery box can be effectively optimized, which is suitable for a variety of actual application scenarios.

[0091] Step 2, when the temperature value is between the second temperature threshold and the first temperature threshold, control the first type of battery pack and the second type of battery pack to charge and discharge each other to heat the battery box; where the second temperature threshold is the minimum value of the minimum rechargeable temperature value of the first type of battery pack and the minimum rechargeable temperature value of the second type of battery; the first temperature threshold is greater than or equal to the maximum value of the minimum rechargeable temperature value of the first type of battery pack and the minimum rechargeable temperature value of the second type of battery.

[0092] For example, the minimum rechargeable temperature value of a lithium iron phosphate battery can be -20°C, and the minimum rechargeable temperature value of a ternary lithium system battery can be 0°C. The first temperature threshold is greater than 0°C. For example, the first temperature threshold can be 1°C, 2°C, 3°C, 4°C, 5°C, 8°C, 10°C, etc.

[0093] Through the above solution, in order to avoid the situation where neither the first type of battery pack nor the second type of battery pack can be charged when the temperature is extremely low. By setting the first temperature threshold and the second temperature threshold, and determining these two thresholds based on the minimum rechargeable temperature values of the two types of battery packs, the lowest temperature range at which the battery boxes can be mutually charged can be accurately determined. The second temperature threshold is the minimum value among the minimum rechargeable temperature values of the two types of batteries. When the temperature is greater than the second temperature threshold and less than the first temperature threshold, the first type of battery pack and the second type of battery pack can self-heat through the heat generated by mutual charging and discharging, so that the temperature value of the battery box can be used even when the external temperature does not meet the operating temperature of the battery box, saving the user's waiting time for heating and improving the user's transportation efficiency.

[0094] Figure 8 This is a partial flowchart of the control method for the battery box provided in this embodiment. Please refer to Figure 8 , in this embodiment, after step 1, it can be step 201. When the temperature value is greater than the third temperature threshold and less than the first temperature threshold, control the first type of battery pack and the second type of battery pack to mutually charge and discharge, where the third temperature threshold is equal to the minimum rechargeable temperature value of the first type of battery pack, and the minimum rechargeable temperature value of the first type of battery pack is the maximum value.

[0095] For example, the first temperature threshold can be 5°C, and the third temperature threshold can be 0°C. When the temperature value is greater than 0°C and less than 5°C, control the first type of battery pack and the second type of battery pack to mutually charge and discharge.

[0096] Through the above embodiments, when the temperature value is within a specific range (between the second temperature threshold and the first temperature threshold), by introducing a third temperature threshold, the temperature control strategy is further refined. This segmented control method can more precisely manage the charging and discharging process of the battery pack, ensuring the safe operation of the battery system under different temperature conditions. By setting the third temperature threshold, the system can flexibly adjust the charging and discharging strategy according to different temperature intervals. This design not only enhances the adaptability of the system but also better copes with complex and changeable environmental conditions. When the temperature is between the third temperature threshold and the first temperature threshold, that is, at this temperature, both types of battery packs can be charged or discharged. Therefore, when the temperature is between the third temperature threshold and the first temperature threshold, they can charge and discharge each other to increase the temperature of the battery box, so that the battery box works within an appropriate temperature range, thereby improving the working efficiency. Moreover, by optimizing the charging and discharging control strategy, the system can maintain efficient operation within a wider temperature range. This design not only improves the overall efficiency of the battery system but also extends the service life of the battery.

[0097] Figure 9 This is a partial flowchart of the control method for the battery box provided in this embodiment. Please refer to Figure 9 , in this embodiment, after step 1, it can be step 202. When the temperature value is greater than the second temperature threshold and less than the third temperature threshold, control the first type of battery pack to charge the second type of battery pack.

[0098] For example, when the temperature value is between -20°C and 5°C, control the first type of battery pack to charge the second type of battery pack.

[0099] Through the above embodiments, since the third temperature threshold is equal to the minimum rechargeable temperature value of the first type of battery pack, when it is less than the third temperature threshold, the first type of battery pack cannot be charged (can only be discharged). Therefore, when the temperature value is greater than the second temperature threshold and less than the third temperature threshold, controlling the first type of battery pack to discharge can effectively avoid charging the first type of battery pack at too low a temperature, reduce the damage to the internal chemical reactions and material structures of the battery at low temperatures, and extend the battery life of the first type of battery pack.

[0100] Figure 10 This is a partial flowchart of the control method for the battery box provided in this embodiment. Please refer to Figure 10 , in this embodiment, after step 1, it can be step 203. When the temperature value is between the second temperature threshold and the first temperature threshold and the total power value of the battery box is greater than or equal to the first power threshold, control the first type of battery pack and the second type of battery pack to charge and discharge each other.

[0101] The total power value is the sum of the power values of the first type of battery pack and the second type of battery pack, and the first power threshold is the minimum dischargeable power value of the battery box. The minimum dischargeable power value of the battery box, i.e., the first power threshold, can be set according to the situation of the battery box and can be 20% SOC, 30% SOC, 40% SOC, etc.

[0102] In this embodiment, the minimum dischargeable power value of the battery box can be 30% SOC. When the total power value of the battery box is greater than or equal to 30% SOC, control the first type of battery pack and the second type of battery pack to charge and discharge with each other.

[0103] Through the above embodiments, when the temperature value is between the second temperature threshold and the first temperature threshold, further combine the total power value of the battery box to perform charge and discharge control. This design not only considers the temperature factor but also introduces the power condition, making the charge and discharge process more accurate and safe. When the total power value of the battery box is greater than or equal to the first power threshold, only then is it allowed for the first type of battery pack and the second type of battery pack to charge and discharge with each other. When the total power value is lower than the first power threshold, stop the mutual charge and discharge between the two types of battery packs, which can effectively avoid the safety problems caused by over-discharge of the battery. Over-discharge will cause the internal voltage of the battery to be too low, which may cause the internal chemical reaction of the battery to be unbalanced, and even lead to battery damage or safety risks. This design ensures that when the battery system conducts energy interaction, there is sufficient power reserve to avoid system failures or performance degradation caused by insufficient power. By introducing the control strategy of dual conditions of temperature and power, the charge and discharge management of the battery system under complex working conditions is optimized. This strategy not only improves the safety, reliability and energy utilization efficiency of the system, but also extends the battery life, enhances the adaptability of the system, and significantly improves the user experience.

[0104] Figure 11 This is a partial flowchart of the control method for the battery box provided in this embodiment. Please refer to Figure 11 In this embodiment, after step 1, it may further include:

[0105] Step 204, obtain the first power value of the first type of battery pack and the second power value of the second type of battery pack.

[0106] Step 205, when the temperature value is between the second temperature threshold and the first temperature threshold, and both the first power value and the second power value are between the second power threshold and the third power threshold, control the first type of battery pack and the second type of battery pack to charge and discharge with each other. The second power threshold is determined according to the minimum dischargeable power value of the first type of battery pack or the minimum dischargeable power value of the second type of battery pack; the third power threshold is determined according to the maximum chargeable power value of the first type of battery pack or the maximum chargeable power value of the second type of battery pack.

[0107] The second power threshold can be 25% SOC, 30% SOC, 40% SOC, etc. The third power threshold can be 90% SOC, 95% SOC, 98% SOC, etc.

[0108] In this embodiment, the minimum dischargeable power value of the first type of battery pack or the minimum dischargeable power value of the second type of battery pack can be 30% SOC, and the maximum chargeable power value of the first type of battery pack or the maximum chargeable power value of the second type of battery pack can be 95% SOC.

[0109] In this embodiment, when the power values of the first type of battery pack and the second type of battery pack are both between 30% SOC and 95% SOC, the first type of battery pack and the second type of battery pack can charge or discharge each other.

[0110] When the power value of the first type of battery pack is lower than 30% SOC and the power value of the second type of battery pack is between 30% SOC and 95% SOC, the second type of battery pack can be controlled to charge the first type of battery pack.

[0111] When the power value of the second type of battery pack is lower than 30% SOC and the power value of the first type of battery pack is between 30% SOC and 95% SOC, the first type of battery pack can be controlled to charge the second type of battery pack.

[0112] The second power threshold is the minimum dischargeable power value of the first type of battery pack or the second type of battery pack. When the power values of both types of battery packs are greater than this threshold, it can ensure that both types of battery packs can provide sufficient electrical energy during discharge. This helps to avoid problems such as unstable operation or sudden power-off of the device due to insufficient power, and improves the reliability of the device and the user experience. The third power threshold is the maximum chargeable power value of the first type of battery pack or the second type of battery pack. When the power values of both types of battery packs are less than this threshold, it can avoid safety problems caused by overcharging of the battery. Overcharging will cause the internal voltage of the battery to be too high, which may cause an imbalance in the internal chemical reaction of the battery, and even lead to battery damage or safety risks. Through the above control method, it can ensure that the battery works within a safe power range and improve the overall safety of the battery system.

[0113] Figure 12 It is a partial flowchart of the control method for the battery box provided in this embodiment. Please refer to Figure 12 In this embodiment, after step 1, the control method may further include:

[0114] Step 110, detecting the temperature value of the battery box and heating or cooling the battery box by an external temperature control method.

[0115] In some embodiments, heating the battery box by an external temperature control method includes: when the temperature value is greater than or equal to the eighth temperature threshold and less than the first temperature threshold, heating the battery box by an external temperature control method to make the temperature value of the battery box higher than the first temperature threshold, where the eighth temperature threshold is less than or equal to the first temperature threshold.

[0116] For example, the first temperature threshold is 5°C, and the eighth temperature threshold is -5°C. When the temperature value is between -5°C and 5°C, the battery box is heated by an external temperature control method to make the temperature value of the battery box higher than 5°C.

[0117] In some embodiments, heating the battery box by an external temperature control method includes: when the temperature value is less than the second temperature threshold, that is, when the temperature is less than the minimum rechargeable temperature value of the first type of battery pack and the minimum rechargeable temperature value of the second type of battery, heating the battery box by an external temperature control method to make the temperature value of the battery box higher than 5°C.

[0118] For example, the minimum value of the minimum rechargeable temperature value of the first type of battery pack and the minimum rechargeable temperature value of the second type of battery is -20°C. When the temperature is less than -20°C, the battery box is heated by an external temperature control method to make the temperature value of the battery box higher than 5°C.

[0119] In some embodiments, heating the battery box by an external temperature control method includes: when the total power value of the battery box is lower than the first power threshold, the first type of battery pack and the second type of battery pack cannot be heated by charging each other. Therefore, an external temperature control method can be selected to increase the temperature of the battery box.

[0120] In some embodiments, heating the battery box by an external temperature control method includes: when the first power value of the first type of battery pack and the second power value of the second type of battery pack are not both between the second power threshold and the third power threshold, and the temperature values are both lower than the second power threshold, the first type of battery pack and the second type of battery pack cannot be heated by charging each other. Therefore, an external temperature control method can be selected to increase the temperature of the battery box.

[0121] In some embodiments, cooling the battery box by an external temperature control method includes: when the temperature value is greater than or equal to the fourth temperature threshold, cooling the battery box by an external temperature control method to make the temperature of the battery box lower than the fourth temperature threshold; the fourth temperature threshold is determined according to the maximum operating temperature of the battery box.

[0122] The maximum operating temperature of the battery box is the maximum value within the temperature range in which the battery box can be safely used. For example, the maximum operating temperature of the battery box is 55°C. When the battery box is used at temperatures exceeding 55°C, safety issues such as thermal runaway may occur. When the temperature value is greater than 55°C, an external temperature control method is used to cool the battery box so that the temperature of the battery box is lower than 55°C.

[0123] In this embodiment, the external temperature control method can be heating or cooling the coolant through a PTC (Positive Temperature Coefficient semiconductor material) or a compressor.

[0124] Through the above embodiments, when the temperature is lower than the first temperature threshold and higher than the eighth temperature threshold, an external heating method is used to raise the temperature above the first temperature threshold to ensure that the battery pack can be safely started and operated in a low-temperature environment. When the temperature is higher than the fourth temperature threshold, an external cooling method is used to prevent the battery box from having an overheating failure due to excessive temperature, avoiding a decline in battery performance or safety hazards caused by high temperature. By strictly controlling the temperature range of the battery box, the battery pack is prevented from operating at extreme temperatures. This design reduces the performance degradation of the battery caused by high or low temperatures, thereby extending the service life of the battery. The use of the external temperature control method is only started when necessary, avoiding unnecessary heating or cooling operations. This strategy not only improves the energy utilization efficiency but also reduces the overall energy consumption of the system. This design further optimizes the temperature control strategy of the battery box by introducing an external temperature control method and combining fine temperature threshold management. It not only improves the safety, reliability, and energy utilization efficiency of the system but also extends the service life of the battery, enhances the adaptability of the system, and significantly improves the user experience. This strategy is particularly suitable for battery management systems that require high safety and high efficiency and can ensure the stable operation of the battery system under complex environmental conditions.

[0125] Figure 13 This is a partial flowchart of the control method for the battery box provided in this embodiment. Please refer to Figure 13 In this embodiment, after step 1 or step 2, the method may further include:

[0126] Step 3, when the temperature value is greater than the first temperature threshold and less than or equal to the fourth temperature threshold, enter the power-on mode.

[0127] For example, when the temperature value is greater than 5°C and less than 55°C, the system is powered on and the battery box is discharged for use.

[0128] Through the above embodiments, by means of the first temperature threshold and the fourth temperature threshold range, the system enters the power-on mode only when the temperature is within the first temperature threshold and the fourth temperature threshold range, that is, it starts to work. This avoids the battery from starting at too low or too high temperatures, thereby reducing potential safety hazards caused by abnormal temperatures. This strategy can effectively prevent failures caused by temperatures exceeding the safe operating range of the battery, such as battery overheating, short circuit, or performance degradation at low temperatures.

[0129] Figure 14 This is a partial flowchart of the control method for the battery box provided in this embodiment. Please refer to Figure 14 , in this embodiment, after step 1 or step 2, the control method further includes:

[0130] Step 4, when the temperature value is between the first temperature threshold and the fifth temperature threshold, control the first type of battery pack and the second type of battery pack to charge and discharge each other so that the temperature value is within the first preset temperature range, where the first preset temperature range is between the sixth temperature threshold and the seventh temperature threshold, the sixth temperature threshold is greater than the fifth temperature threshold, and the seventh temperature threshold is less than the fourth temperature threshold.

[0131] The range between the sixth temperature threshold and the seventh temperature threshold can be understood as a heat preservation temperature. The battery box is more suitable for power-on within this temperature range. Therefore, the temperature value of the battery box can be adjusted between the sixth temperature threshold and the seventh temperature threshold.

[0132] For example, if the fifth temperature threshold is 15 °C, the sixth temperature threshold can be 25 °C, and the seventh temperature threshold can be 35 °C. That is, when the temperature value of the battery box is between 5 °C and 15 °C, control the first type of battery pack and the second type of battery pack to charge and discharge each other so that the temperature of the battery box can reach between the sixth temperature threshold and the seventh temperature threshold, that is, keep the temperature of the battery box between 25 °C and 35 °C.

[0133] Through the above embodiments, when the temperature value is between the first temperature threshold and the fifth temperature threshold, by controlling the charge and discharge between the first type of battery pack and the second type of battery pack, the temperature value is maintained within the first preset temperature range (between the sixth temperature threshold and the seventh temperature threshold). This design realizes the dynamic adjustment of temperature through the energy interaction between the battery packs, avoiding large fluctuations in temperature. Through the charge and discharge between the battery packs, the system can dynamically adjust the temperature to ensure that the battery packs operate within the optimal working temperature range. This strategy not only improves the overall performance of the system but also enhances the energy output efficiency of the battery packs.

[0134] Embodiment 1

[0135] This embodiment also provides a control method for the battery box. Figure 15This is the power-on flowchart of a battery box provided in this embodiment. Please refer to Figure 15 , first, the Battery Management System (BMS) receives the power-on instruction from the vehicle controller. The BMS will detect each control unit in the battery box system. If there is no fault, it will continue to judge the State of Charge (SOC) of the entire battery system (this SOC is the equivalent value of the power of the entire battery box system). If the total power value is greater than 30%, it will start to judge the temperature value of the battery box. If the temperature value exceeds the range of -20°C to 55°C, the system will use an external temperature control method to adjust the temperature of the battery box, for example, enter the external heating mode (such as Figure 17 ) or the external cooling mode (such as Figure 18 ).

[0136] When the temperature value of the battery box is between 5°C and 55°C, the battery box system is controlled to officially enter the power-on mode.

[0137] After entering the power-on mode, the BMS commands both DC / DCs to enter the discharge mode. Then, the BMS battery management system controls the first branch relay, the second branch relay, the main negative relay, the main positive relay, and the water-cooling relay to close, so that both the first converter and the second converter discharge, thereby realizing the power-on mode.

[0138] Figure 16 This is the flowchart of the boost mode of the battery box provided in an embodiment of this application. Please refer to Figure 16 , if the system temperature is between -20°C and 5°C, the system will enter the boost mode. The boost mode is a way of charging and discharging between the first type of battery pack and the second type of battery pack to heat the battery box.

[0139] In this embodiment, after entering the boost mode, the following steps are included:

[0140] First, the BMS compares the temperature and power information in the first type of battery pack and the second type of battery pack.

[0141] Then, according to the charging or discharging requirements of the first type of battery pack and the second type of battery pack, the output power of the first type of battery pack and the second type of battery pack is matched.

[0142] After power-on is completed, the VCU calculates the power demand of the vehicle according to the driver's intention, converts it into current demand, and sends it to the BMS. The BMS sends an instruction to the VCU that the power-on of the battery system has been completed. The BMS distributes power to the first converter (DC / DC-1) and the second converter (DC / DC-2) according to the power demand of the VCU. For example, ternary lithium batteries have high-rate discharge performance. Therefore, during the high-power output process of the vehicle, the BMS will increase the proportion of the output power of DC / DC-2 according to the power demand of the VCU. When the vehicle power demand is low, the BMS mainly provides power through DC / DC-1 to ensure the stable discharge of lithium iron phosphate batteries. For example, when the vehicle power demand is high, the BMS increases the proportion of the output power of DC / DC-2, utilizes the high-rate discharge performance of ternary lithium batteries to meet the high-power demand, and at the same time reduces the discharge rate of lithium iron phosphate batteries. This control strategy can significantly reduce the discharge rate of lithium iron phosphate battery cells, thereby effectively extending their service life.

[0143] Then, mutual charging is carried out, and the charging and discharging functions between branches are realized by controlling the corresponding DC / DC mode. For example, if it is necessary to control the first type of battery pack to discharge and the second type of battery pack to charge, correspondingly, control the relays of the first type of battery pack and the second type of battery pack to be closed so that the first type of battery pack discharges and the second type of battery pack charges.

[0144] During the mutual charging process, monitor the power value of the second type of battery pack, and judge whether the power value of the second type of battery pack is within the range of 30% SOC - 95% SOC. If not, it is necessary to stop the discharge of the second type of battery pack and use an external temperature control method to heat the battery box. If so, monitor whether the temperature value of the first type of battery pack is greater than -5°C. Otherwise, re-detect every 500 ms. If so, control the first solenoid valve to open, then close the water-cooled unit relay, and turn on the PCT water-cooled heating.

[0145] Finally, monitor whether the temperature value of the first type of battery pack is greater than 5°C. Otherwise, re-detect every 500 ms. If so, end the mutual charging, and the system enters the power-on mode.

[0146] Please refer to Figure 17 and Figure 18 , when the temperature of the battery box system exceeds the allowable charge and discharge temperature, the BMS turns on solenoid valve-1 and solenoid valve-2, then closes the water-cooled unit relay, and starts the PTC or compressor to heat or cool the coolant. When the temperature of the branch reaches the predetermined temperature, the system requests to stop the external power supply, and then switches to the charge and discharge mode.

[0147] As Figure 17 shown, after the system requests to heat the battery box by using an external temperature control method, the following steps are included:

[0148] Turn on the first solenoid valve and the second solenoid valve, close the water-cooled unit relay, and start the PTC to heat the coolant.

[0149] Detect whether the temperature of the branches corresponding to the first type of battery pack and the second type of battery pack is greater than 10°C. If not, re-detect every 500 ms. If so, the heating is completed, request to disconnect the external power supply to stop heating, and at this time, the first type of battery pack or the second type of battery is allowed to charge or discharge.

[0150] As Figure 18 shown, after the system requests to cool the battery box by using the external temperature control method, the following steps are included:

[0151] Turn on the first solenoid valve and the second solenoid valve, close the water-cooled unit relay, and start the compressor to cool the coolant.

[0152] Detect whether the temperature of the branches corresponding to the first type of battery pack and the second type of battery pack is less than 35°C. If not, re-detect every 500 ms. If so, the cooling is completed, request to disconnect the external power supply to stop cooling, and at this time, the first type of battery pack or the second type of battery is allowed to charge or discharge.

[0153] Please refer to Figure 19 , for example, when the battery box system is in winter, the external ambient temperature is relatively low. In this embodiment, there is a heat preservation mode for standby, that is, a low-power counter-dragging mode, and the heat preservation function is realized through the low-power counter-dragging mode. Compared with the traditional water-cooled unit heating and heat preservation, the low-power counter-dragging mode can reduce power consumption.

[0154] After the vehicle stops, the BMS disconnects the water-cooled unit relay, then disconnects the main negative and main positive relays, and then controls to enter the low-power counter-dragging mode. During this process, the BMS continuously monitors the lowest temperature of the battery box in the first type of battery pack and the second type of battery pack. If the lowest temperature is less than 15°C, the system turns on the low-power counter-dragging mode.

[0155] The BMS detects the SOC of the first type of battery pack and the second type of battery pack, and judges whether the SOC values of the first type of battery pack and the second type of battery pack are both between 30% and 90%. If not, exit the low-power counter-dragging mode. If so, perform mutual charge and discharge adjustment at fixed intervals. For example, if the first type of battery pack discharges and the second type of battery pack charges before, then after an interval of 5 minutes, control the second type of battery pack to discharge and the first type of battery pack to charge, so as to realize the system to charge and discharge at low power. When the temperature of the battery box is between 25°C and 35°C, the system pauses counter-dragging and enters the sleep standby mode.

[0156] Figure 20 This is the schematic diagram of the control device of the battery box system provided in this embodiment. Please refer toFigure 20 , based on the above embodiments, the present application further provides a control device 500 for a battery box system, including: an acquisition module 510 and a first control module 520. The acquisition module 510 is used to acquire the temperature value of the battery box. Among them, the battery box includes a first type of battery pack and a second type of battery pack, and the battery types of the first type of battery pack and the second type of battery pack are different. The first control module 520 is used to control the first type of battery pack and the second type of battery pack to charge and discharge each other to heat the battery box when the temperature value is between a second temperature threshold and a first temperature threshold; wherein, the second temperature threshold is the minimum of the minimum rechargeable temperature value of the first type of battery pack and the minimum rechargeable temperature value of the second type of battery; the first temperature threshold is greater than or equal to the maximum of the minimum rechargeable temperature value of the first type of battery pack and the minimum rechargeable temperature value of the second type of battery.

[0157] In this embodiment, the first control module may further include a second control module. The second control module is used to control the first type of battery pack and the second type of battery pack to charge and discharge each other when the temperature value is greater than a third temperature threshold and less than the first temperature threshold. Among them, the third temperature threshold is equal to the minimum rechargeable temperature value of the first type of battery pack, and the minimum rechargeable temperature value of the first type of battery pack is the maximum value.

[0158] In this embodiment, the first control module may further include a third control module. The third control module is used to control the first type of battery pack to charge the second type of battery pack when the temperature value is greater than the second temperature threshold and less than the third temperature threshold.

[0159] In this embodiment, the first control module may further include a fourth module. The fourth module is used to control the first type of battery pack and the second type of battery pack to charge and discharge each other when the temperature value is between the second temperature threshold and the first temperature threshold and the total power value of the battery box is greater than or equal to a first power threshold. Among them, the total power value is the sum of the power value of the first type of battery pack and the power value of the second type of battery pack, and the first power threshold is the minimum dischargeable power value of the battery box.

[0160] In this embodiment, the first control module may further include a fifth module. The fifth module is used to acquire the first power value of the first type of battery pack and the second power value of the second type of battery pack; when the temperature value is between the second temperature threshold and the first temperature threshold, and both the first power value and the second power value are between a second power threshold and a third power threshold, control the first type of battery pack and the second type of battery pack to charge and discharge each other, wherein, the second power threshold is determined according to the minimum dischargeable power value of the first type of battery pack or the minimum dischargeable power value of the second type of battery pack; the third power threshold is determined according to the maximum rechargeable power value of the first type of battery pack or the maximum rechargeable power value of the second type of battery pack.

[0161] In this embodiment, a sixth module may also be included. The sixth module is used to detect the temperature value of the battery box. When the temperature value is greater than or equal to the eighth temperature threshold and less than the first temperature threshold, an external temperature control method is used to heat the battery box so that the temperature value of the battery box is higher than the first temperature threshold, where the eighth temperature threshold is less than or equal to the first temperature threshold; or, detect the temperature value of the battery box. When the temperature value is greater than or equal to the fourth temperature threshold, an external temperature control method is used to cool the battery box so that the temperature of the battery box is lower than the fourth temperature threshold; the fourth temperature threshold is determined according to the maximum operating temperature of the battery box.

[0162] A seventh module may also be included. The seventh module is used to enter the power-on mode when the temperature value is greater than the first temperature threshold and less than or equal to the fourth temperature threshold.

[0163] An eighth module may also be included. The eighth module is used to control the charging and discharging between the first type of battery pack and the second type of battery pack when the temperature value is between the first temperature threshold and the fifth temperature threshold, so that the temperature value is within a first preset temperature range, where the first preset temperature range is between the sixth temperature threshold and the seventh temperature threshold, the sixth temperature threshold is greater than the fifth temperature threshold, and the seventh temperature threshold is less than the fourth temperature threshold.

[0164] Based on the above embodiments, the present application further provides an electronic device, including: a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete mutual communication through the communication bus; a computer program is stored in the memory. When the computer program is executed by the processor, the processor executes the steps of any one of the above control methods.

[0165] Based on the above embodiments, the present application further provides a computer-readable storage medium, which stores a computer program executable by an electronic device. When the computer program runs on the electronic device, the electronic device executes the steps of any one of the above control methods.

[0166] Based on the above embodiments, the present application further provides a vehicle, specifically including: an electronic device for implementing any one of the above control methods; a processor, the processor runs a program. When the program runs, it executes the steps of any one of the above control methods for the data output from the electronic device; a storage medium for storing the program. When the program runs, it executes the steps of any one of the above control methods for the data output from the electronic device.

[0167] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for controlling a battery box, characterized in that: The control method comprises: Acquire a temperature value of a battery box, wherein the battery box includes a first type of battery group and a second type of battery group, and the first type of battery group and the second type of battery group have different types of batteries; When the temperature value is between the second temperature threshold and the first temperature threshold, controlling the first type battery pack and the second type battery pack to charge and discharge each other to heat the battery box; Among them, the second temperature threshold is the minimum value of the minimum chargeable temperature value of the first type battery pack and the minimum chargeable temperature value of the second type battery; the first temperature threshold is greater than or equal to the maximum value of the minimum chargeable temperature value of the first type battery pack and the minimum chargeable temperature value of the second type battery.

2. The control method according to claim 1, characterized in that: When the temperature value is between the second temperature threshold and the first temperature threshold, controlling the first type battery pack and the second type battery pack to charge and discharge each other includes: When the temperature value is greater than or equal to a third temperature threshold and less than the first temperature threshold, the first type battery pack and the second type battery pack are controlled to charge and discharge each other, wherein the third temperature threshold is equal to the minimum chargeable temperature value of the first type battery pack, and the minimum chargeable temperature value of the first type battery pack is the maximum value.

3. The control method according to claim 2, characterized in that: When the temperature value is between the second temperature threshold and the first temperature threshold, controlling the first type battery pack and the second type battery pack to charge and discharge each other, further comprising: When the temperature value is greater than or equal to the second temperature threshold and less than the third temperature threshold, the first type battery pack is controlled to charge the second type battery pack.

4. The control method according to any one of claims 1 to 3, characterized in that: When the temperature value is between the second temperature threshold and the first temperature threshold, controlling the first type battery pack and the second type battery pack to charge and discharge each other includes: When the temperature value is between the second temperature threshold and the first temperature threshold, and the total power value of the battery box is greater than or equal to the first power threshold, the first type of battery group and the second type of battery group are controlled to charge and discharge each other, wherein the total power value is the sum of the power value of the first type of battery group and the power value of the second type of battery group, and the first power threshold is the minimum dischargeable power value of the battery box.

5. The control method according to any one of claims 1 to 3, characterized in that: When the temperature value is between the second temperature threshold and the first temperature threshold, controlling the first type battery pack and the second type battery pack to charge and discharge each other, further comprising: Acquire a first power value of the first type of battery pack and a second power value of the second type of battery pack; When the temperature value is between the second temperature threshold and the first temperature threshold, and the first power value and the second power value are both between the second power threshold and the third power threshold, the first type of battery group and the second type of battery group are controlled to charge and discharge each other, wherein the second power threshold is determined according to the minimum dischargeable power value of the first type of battery group or the minimum dischargeable power value of the second type of battery group; and the third power threshold is determined according to the maximum chargeable power value of the first type of battery group or the maximum chargeable power value of the second type of battery group.

6. The control method according to any one of claims 1 to 3, characterized in that: The control method further comprises: detecting a temperature value of the battery box, and when the temperature value is greater than or equal to an eighth temperature threshold and less than the first temperature threshold, heating the battery box in an external temperature control manner so that the temperature value of the battery box is greater than or equal to the first temperature threshold, wherein the eighth temperature threshold is less than the first temperature threshold; or, Detect the temperature value of the battery box. When the temperature value is greater than or equal to a fourth temperature threshold, use an external temperature control method to cool the battery box so that the temperature of the battery box is lower than the fourth temperature threshold. The fourth temperature threshold is determined according to the maximum operating temperature of the battery box.

7. The control method according to claim 6, characterized in that: The control method further comprises: When the temperature value is greater than the first temperature threshold and less than or equal to the fourth temperature threshold, a power-on mode is entered.

8. The control method according to claim 6, characterized in that: The control method further comprises: When the temperature value is between the first temperature threshold and the fifth temperature threshold, the first type of battery group and the second type of battery group are controlled to charge and discharge each other so that the temperature value is within a first preset temperature range, wherein the first preset temperature range is between the sixth temperature threshold and the seventh temperature threshold, the sixth temperature threshold is greater than the fifth temperature threshold, and the seventh temperature threshold is less than the fourth temperature threshold.

9. The control method according to any one of claims 1 to 3, characterized in that: The first type of battery pack is a lithium iron phosphate battery, and the second type of battery pack is a ternary lithium system battery.

10. A control device for a battery box system, characterized in that: include: an acquisition module, configured to acquire a temperature value of a battery box, wherein the battery box comprises a first type of battery pack and a second type of battery pack, and the first type of battery pack and the second type of battery pack have different types of batteries; A first control module is used to control the mutual charging and discharging between the first type battery pack and the second type battery pack to heat the battery box when the temperature value is between the second temperature threshold and the first temperature threshold; wherein the second temperature threshold is the minimum of the minimum chargeable temperature value of the first type battery pack and the minimum chargeable temperature value of the second type battery; and the first temperature threshold is greater than or equal to the maximum of the minimum chargeable temperature value of the first type battery pack and the minimum chargeable temperature value of the second type battery.

11. An electronic device, characterized in that: include: A processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus; a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of the control method described in any one of claims 1 to 9.

12. A computer-readable storage medium, characterized in that: It stores a computer program executable by an electronic device, and when the computer program runs on the electronic device, the electronic device executes the steps of the control method described in any one of claims 1 to 9.

13. A vehicle, characterized in that: Specifically include: An electronic device, used to implement the control method according to any one of claims 1 to 9; a processor, the processor running a program, and when the program is running, executing the steps of the control method according to any one of claims 1 to 9 for data output from the electronic device; A storage medium for storing a program, wherein when the program is run, the program executes the steps of the control method according to any one of claims 1 to 9 for data output from an electronic device.

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