New energy automobile power battery temperature regulation and control system for ultralow temperature environment

Abstract

The invention relates to the technical field of power battery temperature regulation and control, in particular to a new energy automobile power battery temperature regulation and control system for an ultralow-temperature environment, and the system comprises an information collection module which is used for collecting power battery information, insulation information, environment information and automobile running speed, and a mode judgment module which is used for judging the running speed of an automobile. The system comprises a single battery temperature acquisition module used for judging a heating mode according to acquired single battery temperature, an environment analysis module used for analyzing an environment state, a temperature regulation and control module used for controlling heating power of heating equipment according to the environment state, the heating mode, a battery pack icing thickness and an automobile running speed, and an early warning module used for warning the heating power of the heating equipment. The thermal runaway early warning module is used for carrying out thermal runaway early warning to a user, the thermal insulation analysis module is used for analyzing the thermal insulation performance of an insulating material, and the attenuation analysis module is used for processing the power control process of each heating device in the next capacity analysis period. The temperature regulation and control efficiency of the power battery is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power battery temperature control, and in particular to a new energy vehicle power battery temperature control system for use in an ultra-low temperature environment. Background Art

[0002] With the rapid development of new energy vehicles, power batteries, as their core components, have a direct impact on the vehicle's range and safety. However, in ultra-low temperature environments, the performance of power batteries will drop significantly, resulting in battery capacity attenuation, reduced charging and discharging efficiency, and may even cause safety issues such as thermal runaway. Most of the existing battery temperature control technologies only regulate the discharge power of the battery, lacking comprehensive consideration of complex environmental factors, especially in ultra-low temperature environments. The temperature control efficiency of the battery is low and it is difficult to meet actual needs. Therefore, the development of a system that can efficiently regulate the temperature of power batteries in ultra-low temperature environments has become a technical problem that needs to be urgently solved in the field of new energy vehicles.

[0003] Chinese patent publication number CN113415210A discloses a battery temperature control method, device and automobile, the method comprising: obtaining the temperature of multiple test points of the battery in the discharge mode to determine the average battery temperature, the maximum battery temperature and the minimum battery temperature; determining the battery temperature change value according to the average battery temperature and the real-time battery remaining power; determining the first temperature threshold and the second temperature threshold according to the battery temperature change value, the maximum battery temperature and the minimum battery temperature; obtaining the first real-time discharge power; determining the first real-time battery temperature according to the first real-time discharge power; when judging the magnitude relationship between the first real-time battery temperature and the first temperature threshold or the second temperature threshold, controlling the temperature control device to cool or heat the battery. Based on the different discharge powers, the threshold range of the battery temperature is predicted, so that the battery temperature is controlled within the ideal range, unnecessary energy consumption is reduced, and the cruising range of the electric vehicle is effectively extended; it can be seen that the scheme only performs temperature control on the discharge power of the battery, and does not take into account the complex environment, and there is a problem of low efficiency in power battery temperature control. Summary of the invention

[0004] The object of the present invention is to provide a temperature control system for a new energy vehicle power battery in an ultra-low temperature environment to solve at least one of the problems existing in the prior art.

[0005] To achieve the above object, the present invention adopts the following technical solutions: A temperature control system for a new energy vehicle power battery in an ultra-low temperature environment, comprising: Information collection module, used to collect power battery information, insulation information, environmental information and vehicle driving speed; Environmental analysis module, used to analyze environmental status based on environmental data collected during the monitoring period; A temperature control module, for controlling the heating power of the heating device according to the environmental state, the heating mode, the ice thickness of the battery pack and the driving speed of the vehicle, the temperature control module includes a control unit, a freezing analysis unit and a speed analysis unit, the control unit is used to control the power of each heating device according to the analysis result of the environmental state in the monitoring period and the heating mode, the freezing analysis unit is used to process the control process of the power of each heating device according to the ice thickness of the battery pack collected in the monitoring period, and the speed analysis unit is used to process the analysis process of the freezing state of the battery pack according to the driving speed of the vehicle collected in the monitoring period; The attenuation analysis module is used to process the power control process of each heating device in the next capacity analysis cycle according to the battery capacity attenuation, insulation material thermal insulation performance and thermal runaway warning results collected during the capacity analysis cycle.

[0006] Furthermore, it also includes a mode judgment module for judging a heating mode according to the collected single battery temperature, wherein the heating mode includes a primary mode, a secondary mode and no heating.

[0007] Furthermore, the environmental analysis module compares the environmental wind speed v0 collected during the monitoring period with the preset wind speed v1 to analyze the wind speed abnormality, and when the wind speed is abnormal, sets the wind speed abnormality coefficient to FY; The environmental analysis module also compares the environmental temperature t0 collected during the monitoring period with the preset environmental temperature t1 to analyze the abnormality of the environmental temperature, and sets the temperature abnormality coefficient to WY when the environmental temperature is abnormal; The environmental analysis module analyzes the environmental status within the monitoring period according to the wind speed anomaly coefficient and the temperature anomaly coefficient within the monitoring period. If FY+WY≤u0, the environmental analysis module determines that the environmental status within the monitoring period is normal. Otherwise, the environmental analysis module determines that the environmental status within the monitoring period is abnormal, and u0 is the preset environmental status coefficient.

[0008] Furthermore, the control unit controls the power of each heating device according to the analysis result of the environmental state within the monitoring period and the heating mode, wherein: When the heating mode is the first-level mode, if the environmental state is normal, the control unit controls the power of the first heating device to P1, sets P1=p1, and controls the power of the second heating device to P2, sets P2=p2; if the environmental state is abnormal, the control unit controls the power of the first heating device to P3, sets: P3=p1×{1+α1×lg[3×(FY+WY-u0)] / lg4}; and controls the power of the second heating device to P4, sets: P4=p2×[1+α2×(FY+WY-u0)]; When the heating mode is the secondary mode, if the environmental state is normal, the control unit controls the power of the first heating device to P5, setting P5=p1, and controls the power of the second heating device to P6, setting P6=0; if the environmental state is abnormal, the control unit controls the power of the first heating device to P7, setting: P7=p1×{1+α1×lg[3×(FY+WY-u0)] / lg4}; and controls the power of the second heating device to P8, setting: P8=0; When the heating mode is no heating, the control unit controls the power of the first heating device and the second heating device to P9, setting P9=0; Among them, p1 is the first preset heating power, p2 is the second preset heating power, α1 is the first preset adjustment coefficient, and α2 is the second preset adjustment coefficient.

[0009] Furthermore, the freezing analysis unit analyzes the freezing state of the battery pack according to the battery pack ice thickness h0 and the preset thickness h1 collected during the monitoring period, and processes the control process of the power of each heating device according to the analysis result, wherein: If h0≤h1, the freezing analysis unit determines that the freezing state of the battery pack in the current monitoring period is normal; otherwise, the freezing analysis unit determines that the freezing state of the battery pack in the current monitoring period is abnormal; The freezing analysis unit processes the control process of the power of each heating device when the freezing state of the battery pack is abnormal, and sets the processed first preset adjustment coefficient as α1' and the processed second preset adjustment coefficient as α2'.

[0010] Furthermore, the speed analysis unit analyzes the driving state of the vehicle according to the vehicle driving speed q0 collected during the monitoring period and the preset driving speed q1, and processes the analysis process of the freezing state of the battery pack according to the analysis result, wherein: If q0≤q1, the speed analysis unit determines that the driving state of the vehicle in the current monitoring period is a normal state, otherwise, the speed analysis unit determines that the driving state of the vehicle in the current monitoring period is a high-speed state; The speed analysis unit processes the analysis process of the frozen state of the battery pack when the vehicle is traveling at a high speed, and sets the processed preset thickness to h2.

[0011] Furthermore, it also includes an early warning module, which is used to issue a thermal runaway early warning to the user according to the temperature rise rate of the single battery collected during the management period; the early warning module includes a temperature rise monitoring unit, which is used to analyze the abnormality of the temperature rise rate of the single battery during the management period according to the temperature rise rate of the single battery collected during the management period and the preset temperature rise rate s0, wherein: If si≤s1, the temperature rise monitoring unit determines that the temperature rise rate of the i-th single battery is normal, otherwise, the temperature rise monitoring unit determines that the temperature rise rate of the i-th single battery is abnormal; The temperature rise monitoring unit is also used to calculate the temperature rise uniformity coefficient Y according to the temperature rise rate of the single battery collected during the management period, where si is the temperature rise rate of the i-th single battery collected during the management period; The warning module also includes a warning unit, which is used to analyze the temperature rise state of the power battery according to the abnormality of the temperature rise rate of the single battery and the temperature rise uniformity coefficient Y within the management period, and to issue a thermal runaway warning to the user according to the analysis result, wherein: If exp[3×(j1 / I)-3]+Y≤L, the early warning unit determines that the temperature rise state of the power battery in the current management cycle is normal, and does not issue a thermal runaway warning to the user; otherwise, the early warning unit determines that the temperature rise state of the power battery in the current management cycle is abnormal, and issues a thermal runaway warning to the user; Wherein, j1 is the number of single cells with abnormal temperature rise rate during the management cycle, and L is the preset temperature rise state threshold.

[0012] Furthermore, it also includes a thermal insulation analysis module, which is used to analyze the thermal insulation coefficient G of the insulating material according to the collected thickness d0 of the insulating material and the thermal conductivity γ of the insulating material, and set G=A×(d0 / d1)×(γ / γ1), where A is the proportional index, d1 is the thickness threshold, and γ1 is the thermal conductivity threshold; The thermal insulation analysis module analyzes the thermal insulation performance of the insulating material according to the thermal insulation coefficient G and the thermal insulation coefficient threshold G0. If G≤G0, the thermal insulation analysis module determines that the thermal insulation performance of the insulating material is low insulation. Otherwise, the thermal insulation analysis module determines that the thermal insulation performance of the insulating material is high insulation.

[0013] Furthermore, the attenuation analysis module includes a capacity analysis unit for analyzing the capacity attenuation state according to the battery capacity attenuation rs0 and the preset capacity attenuation rs1 collected during the capacity analysis period, wherein: If rs0≤rs1, the capacity analysis unit determines that the battery capacity attenuation state in the current capacity analysis cycle is a normal state. Otherwise, the capacity analysis unit determines that the battery capacity attenuation state in the current capacity analysis cycle is an abnormal state.

[0014] Furthermore, the attenuation analysis module includes a control processing unit, which processes the power control process of the heating device in the next capacity analysis cycle according to the capacity attenuation state, the thermal insulation performance of the insulating material and the thermal runaway warning result, wherein: When the capacity attenuation state is normal and the thermal insulation performance of the insulating material is low, if r0 / R≤η, the control processing unit sets the second preset heating power to pp1, setting pp1=p2; if r0 / R>η, the control processing unit sets the second preset heating power to pp2, setting pp2=p2×[1-B×(r0 / R-η) 1.5 ]; When the capacity attenuation state is abnormal and the thermal insulation performance of the insulating material is low, if r0 / R≤η, the control processing unit sets the second preset heating power to pp3, and sets pp1=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]}; if r0 / R>η, the control processing unit sets the second preset heating power to pp4, and sets pp4=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]-B×(r0 / R-η) 1.5}; When the capacity attenuation state is normal and the thermal insulation performance of the insulating material is high, if r0 / R≤η, the control processing unit sets the second preset heating power to pp5, setting pp5=p2; if r0 / R>η, the control processing unit sets the second preset heating power to pp6, setting pp6=p2×[1-(r0 / R-η) 1.5 ]; When the capacity attenuation state is abnormal and the thermal insulation performance of the insulating material is high, if r0 / R≤η, the control processing unit sets the second preset heating power to pp7, setting pp7=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]}; if r0 / R>η, the control processing unit sets the second preset heating power to pp8, setting pp8=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]-B×(r0 / R-η) 1.5}; Among them, r0 is the number of management cycles for providing thermal runaway warning to users within the capacity analysis cycle, R is the number of management cycles within the capacity analysis cycle, η is the preset abnormal ratio, and B is the preset adjustment ratio coefficient.

[0015] The beneficial effects of the present invention are as follows: through the coordinated work of the information acquisition module, the mode judgment module, the environmental analysis module, the temperature control module, the early warning module, the thermal insulation analysis module and the attenuation analysis module, the battery status, environmental conditions and vehicle driving status can be monitored in real time, and the heating strategy can be dynamically adjusted according to these data. The system can effectively improve the temperature control efficiency of the power battery in an ultra-low temperature environment, ensure the normal operation of the battery in an extreme environment, extend the service life of the battery, and prevent safety issues such as thermal runaway. In addition, the system avoids unnecessary energy consumption through intelligent heating mode judgment and power control, further improving the cruising range and energy utilization efficiency of new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 This is a schematic diagram of the structure of the temperature control system of the power battery of a new energy vehicle used in an ultra-low temperature environment according to this embodiment.

[0018] Figure 2 Schematic diagram of the structure of the temperature control module of this embodiment.

[0019] Figure 3 Schematic diagram of the structure of the early warning module of this embodiment.

[0020] Figure 4 Schematic diagram of the structure of the attenuation analysis module of this embodiment. DETAILED DESCRIPTION

[0021] In order to more clearly illustrate the present invention, the present invention is further described below in conjunction with preferred embodiments and accompanying drawings. Similar components in the accompanying drawings are represented by the same reference numerals. It should be understood by those skilled in the art that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0022] It should be noted that, although the terms first, second, third, etc. may be used to describe in the embodiments of the present application, these descriptions should not be limited to these terms. These terms are only used to distinguish the descriptions. For example, without departing from the scope of the embodiments of the present application, the first may also be referred to as the second, and similarly, the second may also be referred to as the first.

[0023] See also Figure 1As shown, it is a structural schematic diagram of the temperature control system of a new energy vehicle power battery in an ultra-low temperature environment in this embodiment, and the system includes: The information collection module is used to collect power battery information, insulation information, environmental information and vehicle driving speed. The power battery information includes single cell temperature, single cell temperature rise rate, battery capacity attenuation and battery pack ice thickness. The battery pack ice thickness is the thickness of the ice layer of the battery pack shell. The insulation information includes the thermal conductivity of the insulation material and the thickness of the insulation material. The environmental information includes the ambient wind speed and the ambient temperature. In this embodiment, no specific limitation is made on the collection method of the power battery information, the insulation information and the vehicle driving speed. Those skilled in the art can freely set it as long as the collection requirements of the power battery information, the insulation information and the vehicle driving speed are met. Among them, the single cell temperature and the single cell temperature rise rate can be collected by a temperature sensor. The battery capacity attenuation is 1-the ratio of the current maximum capacity of the battery to the initial capacity, which can be collected by a battery management system. The battery pack ice thickness can be collected by an ultrasonic sensor or a laser ranging sensor. The insulation information can be collected interactively. The ambient wind speed can be collected by a wind speed sensor. The ambient temperature can be collected by a temperature sensor. The vehicle driving speed can be collected by a vehicle speed sensor.

[0024] Please continue reading Figure 1 As shown, the system also includes: A mode judgment module is connected to the information collection module, and is used to judge the heating mode according to the collected single battery temperature, wherein: If Tpj≤T1, the mode determination module determines that the heating mode is the first-level mode; If T1<Tpj≤T2, the mode determination module determines that the heating mode is the secondary mode; If Tpj>T2, the mode determination module determines that the heating mode is non-heating; Where, Tpj is the average temperature of each single battery, , Ti is the temperature of the i-th single cell, I is the number of single cells, T1 is the first preset temperature, T2 is the second preset temperature, and T1<T2; the mode judgment module judges the heating mode according to the collected single cell temperature, and through different heating modes, the system can accurately control according to the actual temperature requirements of the battery to avoid overheating or unnecessary energy consumption. At the same time, through intelligent judgment of the heating mode, the system can heat according to the actual needs of the battery, avoid energy waste, and improve heating efficiency.

[0025] Specifically, the first-level mode described in this embodiment is to heat the battery pack together by the first heating device and the second device, and the second-level mode is to heat the battery pack by the first heating device, the first heating device is an electric heating film layer, and the second heating device is a PTC auxiliary heater; in this embodiment, there is no specific limitation on the setting of each heating device, and technical personnel in this field can set it freely as long as the setting requirements of the heating device are met.

[0026] It is understandable that the present embodiment does not specifically limit the setting of each preset temperature, and those skilled in the art can freely set it as long as the setting requirements of each preset temperature are met, among which the best value of T1 is 0°C, and the best value of T2 is 10°C.

[0027] Please continue reading Figure 1 As shown, the system also includes: An environmental analysis module is connected to the information collection module. The environmental analysis module is used to compare the environmental wind speed v0 collected during the monitoring period with the preset wind speed v1 to analyze the abnormality of the wind speed. If v0≤v1, the environmental analysis module determines that the wind speed is normal. If v0>v1, the environmental analysis module determines that the wind speed is abnormal, and sets the wind speed abnormality coefficient to FY, setting FY=k×[(v0-v1) / (v0+v1)] 2 , k is the wind speed adjustment coefficient; The environmental analysis module is also used to compare the ambient temperature t0 collected during the monitoring period with the preset ambient temperature t1 to analyze the abnormality of the ambient temperature. If t0≤t1, the environmental analysis module determines that the ambient temperature is abnormal, and sets the temperature abnormality coefficient to WY, setting WY=exp[-(t1-t0) / △t], where △t is the preset temperature difference; if t0>t1, the environmental analysis module determines that the ambient temperature is normal; The environmental analysis module analyzes the environmental status within the monitoring period according to the wind speed anomaly coefficient and the temperature anomaly coefficient within the monitoring period, wherein: If FY+WY≤u0, the environmental analysis module determines that the environmental state within the monitoring period is normal; otherwise, the environmental analysis module determines that the environmental state within the monitoring period is abnormal, and u0 is a preset environmental state coefficient; the environmental analysis module determines whether the environmental state is abnormal by analyzing the ambient wind speed and ambient temperature. By analyzing the environmental state, the system can adjust the heating strategy according to the environmental conditions to ensure the normal operation of the battery in harsh environments. At the same time, by real-time analysis of the environmental state, the system can dynamically adjust the heating power to ensure the temperature control effect of the battery under different environmental conditions.

[0028] Specifically, when the wind speed is normal, the value of FY is 0, and when the ambient temperature is normal, the value of WY is 0. It can be understood that the present embodiment does not specifically limit the setting of the monitoring period, and those skilled in the art can freely set it as long as the setting requirements of the monitoring period are met, wherein the monitoring period can be set to 1 second.

[0029] It can be understood that, in this embodiment, there is no specific limitation on the setting of the preset wind speed, wind speed adjustment coefficient, preset ambient temperature, preset temperature difference and preset environmental state coefficient. Those skilled in the art can set them freely, and they only need to meet the setting requirements of the preset wind speed, wind speed adjustment coefficient, preset ambient temperature, preset temperature difference and preset environmental state coefficient. Among them, the optimal value of v1 is 8m / s, the optimal value of k is 0.43, the optimal value of t1 is -10℃, the optimal value of △t is 50℃, and the optimal value of u0 is 0.18.

[0030] Please continue reading Figure 1 As shown, the system also includes: A temperature control module is connected to the mode judgment module and the environment analysis module, and is used to control the heating power of the heating device according to the environmental conditions, heating mode, ice thickness of the battery pack and the driving speed of the vehicle.

[0031] See also Figure 2 As shown, the temperature control module includes: The control unit is used to control the power of each heating device according to the analysis results of the environmental status during the monitoring period and the heating mode, wherein: When the heating mode is the first-level mode, if the environmental state is normal, the control unit controls the power of the first heating device to P1, sets P1=p1, and controls the power of the second heating device to P2, sets P2=p2; if the environmental state is abnormal, the control unit controls the power of the first heating device to P3, sets: P3=p1×{1+α1×lg[3×(FY+WY-u0)] / lg4}; and controls the power of the second heating device to P4, sets: P4=p2×[1+α2×(FY+WY-u0)]; When the heating mode is the secondary mode, if the environmental state is normal, the control unit controls the power of the first heating device to P5, setting P5=p1, and controls the power of the second heating device to P6, setting P6=0; if the environmental state is abnormal, the control unit controls the power of the first heating device to P7, setting: P7=p1×{1+α1×lg[3×(FY+WY-u0)] / lg4}; and controls the power of the second heating device to P8, setting: P8=0; When the heating mode is no heating, the control unit controls the power of the first heating device and the second heating device to P9, setting P9=0; Among them, p1 is the first preset heating power, p2 is the second preset heating power, α1 is the first preset adjustment coefficient, and α2 is the second preset adjustment coefficient; the control unit controls the heating power of the heating equipment according to the environmental conditions, heating mode, ice thickness of the battery pack and the driving speed of the vehicle to accurately control the heating power. At the same time, by dynamically adjusting the heating power, the system can accurately control according to the actual needs of the battery, avoid energy waste, and improve heating efficiency.

[0032] It can be understood that, in this embodiment, there is no specific limitation on the setting of each preset heating power and each preset adjustment coefficient, and those skilled in the art can set them freely, as long as there is no setting requirement for each preset heating power and each preset adjustment coefficient in this embodiment. Among them, the optimal value of p1 is 100W, the optimal value of p2 is 50W, the optimal value of α1 is 0.5, and the optimal value of α2 is 0.3.

[0033] Please continue reading Figure 2 As shown, the temperature control module also includes: A freezing analysis unit connected to the control unit is used to analyze the freezing state of the battery pack according to the ice thickness h0 of the battery pack collected during the monitoring period and the preset thickness h1, and process the control process of the power of each heating device according to the analysis result, wherein: If h0≤h1, the freezing analysis unit determines that the freezing state of the battery pack in the current monitoring period is normal; otherwise, the freezing analysis unit determines that the freezing state of the battery pack in the current monitoring period is abnormal; The freezing analysis unit processes the control process of the power of each heating device when the freezing state of the battery pack is abnormal, and sets the first preset adjustment coefficient after processing to α1', setting α1'=α1×ln[e+4×(h0-h1) / (h0+h1)+1] / ln5, and sets the second preset adjustment coefficient after processing to α2', setting α2'=α2×ln[e+4×(h0-h1) / (h0+h1)+1] / ln5, where e is the natural logarithm; the freezing analysis unit monitors the ice thickness in real time, and the system can adjust the heating power in time to ensure the normal operation of the battery pack in a low temperature environment and avoid temperature control failure due to ice.

[0034] It can be understood that, in this embodiment, no specific limitation is imposed on the value of the preset thickness, and those skilled in the art can freely set it as long as the setting requirements of the preset thickness are met, wherein the best value of h1 is 1 mm.

[0035] Please continue reading Figure 2 As shown, the temperature control module also includes: A speed analysis unit connected to the freezing analysis unit, the speed analysis unit is used to analyze the driving state of the vehicle according to the vehicle driving speed q0 collected during the monitoring period and the preset driving speed q1, and process the analysis process of the freezing state of the battery pack according to the analysis result, wherein: If q0≤q1, the speed analysis unit determines that the driving state of the vehicle in the current monitoring period is a normal state, otherwise, the speed analysis unit determines that the driving state of the vehicle in the current monitoring period is a high-speed state; The speed analysis unit processes the analysis process of the frozen state of the battery pack when the vehicle is in a high-speed driving state, and sets the processed preset thickness to h2, setting h2=h1×{1+[(q0-q1) / q0] E}, E is the speed correction index; the speed analysis unit analyzes the freezing state of the battery pack according to the driving speed of the vehicle, and adjusts the heating strategy according to the analysis result. By analyzing the driving speed, the system can adjust the heating power according to the driving state of the vehicle to ensure the temperature control effect of the battery under different driving states.

[0036] It can be understood that the present embodiment does not specifically limit the setting of the preset driving speed and the speed correction index, and those skilled in the art can freely set them as long as the setting requirements of the preset driving speed and the speed correction index are met, wherein the optimal value of q1 is 100 km / h, and the optimal value of E is 2.3.

[0037] Please continue reading Figure 1 As shown, the system also includes: An early warning module is connected to the temperature control module, and the early warning module is used to provide a thermal runaway early warning to the user according to the temperature rise rate of the single battery collected during the management period. In this embodiment, no specific limitation is made to the setting of the management period, and those skilled in the art can set it freely, as long as the setting requirements of the management period are met. Among them, the setting of the management period should be greater than the setting of the monitoring period, and the management period can be set to 5 minutes, 6 minutes, etc.

[0038] See also Figure 3 As shown, the early warning module includes: The temperature rise monitoring unit is used to analyze the abnormality of the temperature rise rate of the single cell in the management period according to the temperature rise rate of the single cell collected in the management period and the preset temperature rise rate s0, wherein: If si≤s0, the temperature rise monitoring unit determines that the temperature rise rate of the i-th single battery is normal, otherwise, the temperature rise monitoring unit determines that the temperature rise rate of the i-th single battery is abnormal; The temperature rise monitoring unit is also used to calculate the temperature rise uniformity coefficient Y according to the temperature rise rate of the single battery collected during the management period, and set: ; Wherein, si is the temperature rise rate of the ith single cell collected during the management cycle.

[0039] It is understandable that the present embodiment does not specifically limit the setting of the preset temperature rise rate, and those skilled in the art can freely set it as long as the setting requirements of the preset temperature rise rate are met, wherein the best value of s0 is 3°C / min.

[0040] Please continue reading Figure 3 As shown, the early warning module also includes: The early warning unit is used to analyze the temperature rise state of the power battery according to the abnormality of the temperature rise rate of the single battery and the temperature rise uniformity coefficient Y during the management cycle, and to issue a thermal runaway early warning to the user based on the analysis results, including: If exp[3×(j1 / I)-3]+Y≤L, the early warning unit determines that the temperature rise state of the power battery in the current management cycle is normal, and does not issue a thermal runaway warning to the user; otherwise, the early warning unit determines that the temperature rise state of the power battery in the current management cycle is abnormal, and issues a thermal runaway warning to the user; Wherein, j1 is the number of single cells with abnormal temperature rise rate during the management cycle, and L is the preset temperature rise state threshold; the warning unit performs thermal runaway warning according to the temperature rise rate of the single cell to ensure that timely measures can be taken when the battery temperature is abnormal. Through the warning mechanism, the system can prevent the battery from overheating and ensure the safe operation of the battery.

[0041] It can be understood that, in this embodiment, the setting of the preset temperature rise state threshold is not specifically limited, and those skilled in the art can set it freely, as long as the setting requirements of the preset temperature rise state threshold are met, wherein the optimal value of L is 0.46.

[0042] Please continue reading Figure 1 As shown, the system comprises: A thermal insulation analysis module, which is connected to the early warning module, and is used to analyze the thermal insulation coefficient G of the insulating material according to the collected thickness d0 of the insulating material and the thermal conductivity γ of the insulating material, and set G=A×(d0 / d1)×(γ / γ1), where A is a proportional index, d1 is a thickness threshold, and γ1 is a thermal conductivity threshold; The thermal insulation analysis module analyzes the thermal insulation performance of the insulating material according to the thermal insulation coefficient G and the thermal insulation coefficient threshold G0. If G≤G0, the thermal insulation analysis module determines that the thermal insulation performance of the insulating material is low, otherwise, the thermal insulation analysis module determines that the thermal insulation performance of the insulating material is high; the thermal insulation analysis module analyzes the thermal insulation performance of the insulating material according to its thickness and thermal conductivity to ensure the thermal insulation effect of the battery pack. By analyzing the thermal insulation performance, the system can adjust the heating strategy according to the actual performance of the insulating material to ensure the normal operation of the battery in a low temperature environment.

[0043] It can be understood that, in this embodiment, there is no specific limitation on the setting of the proportional index, thickness threshold, thermal conductivity threshold and thermal insulation coefficient threshold, and those skilled in the art can set them freely as long as the setting requirements of the proportional index, thickness threshold, thermal conductivity threshold and thermal insulation coefficient threshold are met. Among them, the optimal value of A is 0.6, the optimal value of d1 is 5 mm, the optimal value of γ1 is 0.1 W / m·K, and the optimal value of G0 is 0.7.

[0044] Please continue reading Figure 1 As shown, the system also includes: An attenuation analysis module is connected to the thermal insulation analysis module, and the attenuation analysis module is used to process the power control process of each heating device in the next capacity analysis cycle according to the battery capacity attenuation, the thermal insulation performance of the insulating material and the thermal runaway warning results collected during the capacity analysis cycle; it can be understood that the present embodiment does not specifically limit the setting of the capacity analysis cycle, and those skilled in the art can set it freely, as long as the setting requirements of the capacity analysis cycle are met, wherein the setting of the capacity analysis cycle should be greater than the setting of the management cycle, and the capacity analysis cycle can be set to 20 days, 30 days, etc., and the battery capacity attenuation collected during the capacity analysis cycle is collected at the beginning of the capacity analysis cycle.

[0045] See also Figure 4 As shown, the attenuation analysis module includes: The capacity analysis unit is used to analyze the capacity decay state according to the battery capacity decay rs0 and the preset capacity decay rs1 collected during the capacity analysis period, wherein: If rs0≤rs1, the capacity analysis unit determines that the battery capacity decay state in the current capacity analysis cycle is a normal state, otherwise, the capacity analysis unit determines that the battery capacity decay state in the current capacity analysis cycle is an abnormal state; the capacity analysis unit analyzes the capacity decay state according to the battery capacity decay to ensure that the system can adjust the heating strategy according to the actual capacity decay of the battery. By analyzing the capacity decay, the system can optimize the heating power to ensure the temperature control effect of the battery in long-term use.

[0046] It can be understood that the present embodiment does not specifically limit the setting of the preset capacity decay, and those skilled in the art can freely set it as long as the setting requirements of the preset capacity decay are met, wherein the optimal value of rs1 is 0.15.

[0047] Please continue reading Figure 4 As shown, the attenuation analysis module includes: A control processing unit is connected to the capacity analysis unit, and the control processing unit processes the power control process of the heating device in the next capacity analysis cycle according to the capacity attenuation state, the thermal insulation performance of the insulating material and the thermal runaway warning result, wherein: When the capacity attenuation state is normal and the thermal insulation performance of the insulating material is low, if r0 / R≤η, the control processing unit sets the second preset heating power to pp1, setting pp1=p2; if r0 / R>η, the control processing unit sets the second preset heating power to pp2, setting pp2=p2×[1-B×(r0 / R-η) 1.5 ]; When the capacity attenuation state is abnormal and the thermal insulation performance of the insulating material is low, if r0 / R≤η, the control processing unit sets the second preset heating power to pp3, and sets pp1=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]}; if r0 / R>η, the control processing unit sets the second preset heating power to pp4, and sets pp4=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]-B×(r0 / R-η) 1.5}; When the capacity attenuation state is normal and the thermal insulation performance of the insulating material is high, if r0 / R≤η, the control processing unit sets the second preset heating power to pp5, setting pp5=p2; if r0 / R>η, the control processing unit sets the second preset heating power to pp6, setting pp6=p2×[1-(r0 / R-η) 1.5 ]; When the capacity attenuation state is abnormal and the thermal insulation performance of the insulating material is high, if r0 / R≤η, the control processing unit sets the second preset heating power to pp7, setting pp7=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]}; if r0 / R>η, the control processing unit sets the second preset heating power to pp8, setting pp8=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]-B×(r0 / R-η) 1.5}; Among them, r0 is the number of management cycles for issuing thermal runaway warnings to users within the capacity analysis cycle, R is the number of management cycles within the capacity analysis cycle, η is the preset abnormal ratio, and B is the preset adjustment ratio coefficient; the control processing unit processes the power control process of the heating device in the next capacity analysis cycle according to the capacity attenuation state, the thermal insulation performance of the insulating material and the thermal runaway warning result. By comprehensively analyzing multiple factors, the system can optimize the heating strategy, ensure the temperature control effect of the battery in long-term use, and extend the battery life.

[0048] It can be understood that, in this embodiment, the setting of the preset abnormal ratio and the preset adjustment proportional coefficient is not specifically limited, and those skilled in the art can set them freely, as long as the setting requirements of the preset abnormal ratio and the preset adjustment proportional coefficient are met, where the optimal value of η is 0.05, and the optimal value of B is 0.9.

[0049] The temperature control system of the present invention can be widely used in new energy vehicles, especially in new energy vehicles used in cold areas or in winter.

[0050] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the embodiments here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A temperature control system for a new energy vehicle power battery in an ultra-low temperature environment, characterized in that: include: Information collection module, used to collect power battery information, insulation information, environmental information and vehicle driving speed; Environmental analysis module, used to analyze environmental status based on environmental data collected during the monitoring period; A temperature control module, for controlling the heating power of the heating device according to the environmental state, the heating mode, the ice thickness of the battery pack and the driving speed of the vehicle, the temperature control module includes a control unit, a freezing analysis unit and a speed analysis unit, the control unit is used to control the power of each heating device according to the analysis result of the environmental state in the monitoring period and the heating mode, the freezing analysis unit is used to process the control process of the power of each heating device according to the ice thickness of the battery pack collected in the monitoring period, and the speed analysis unit is used to process the analysis process of the freezing state of the battery pack according to the driving speed of the vehicle collected in the monitoring period; The attenuation analysis module is used to process the power control process of each heating device in the next capacity analysis cycle according to the battery capacity attenuation, insulation material thermal insulation performance and thermal runaway warning results collected during the capacity analysis cycle.

2. The temperature control system for new energy vehicle power batteries in ultra-low temperature environments according to claim 1 is characterized in that: It also includes a mode judgment module for judging a heating mode according to the collected single battery temperature, wherein the heating modes include a primary mode, a secondary mode and no heating.

3. The temperature control system for new energy vehicle power battery in ultra-low temperature environment according to claim 2 is characterized in that: The environmental analysis module compares the environmental wind speed v0 collected during the monitoring period with the preset wind speed v1 to analyze the wind speed abnormality, and when the wind speed is abnormal, the wind speed abnormality coefficient is set to FY; The environmental analysis module also compares the environmental temperature t0 collected during the monitoring period with the preset environmental temperature t1 to analyze the abnormality of the environmental temperature, and sets the temperature abnormality coefficient to WY when the environmental temperature is abnormal; The environmental analysis module analyzes the environmental status within the monitoring period according to the wind speed anomaly coefficient and the temperature anomaly coefficient within the monitoring period. If FY+WY≤u0, the environmental analysis module determines that the environmental status within the monitoring period is normal. Otherwise, the environmental analysis module determines that the environmental status within the monitoring period is abnormal, and u0 is the preset environmental status coefficient.

4. The temperature control system for new energy vehicle power battery in ultra-low temperature environment according to claim 3 is characterized in that: The control unit controls the power of each heating device according to the analysis results of the environmental state within the monitoring period and the heating mode, wherein: When the heating mode is the first-level mode, if the environmental state is normal, the control unit controls the power of the first heating device to P1, sets P1=p1, and controls the power of the second heating device to P2, sets P2=p2; if the environmental state is abnormal, the control unit controls the power of the first heating device to P3, sets: P3=p1×{1+α1×lg[3×(FY+WY-u0)] / lg4}; and controls the power of the second heating device to P4, sets: P4=p2×[1+α2×(FY+WY-u0)]; When the heating mode is the secondary mode, if the environmental state is normal, the control unit controls the power of the first heating device to P5, setting P5=p1, and controls the power of the second heating device to P6, setting P6=0; if the environmental state is abnormal, the control unit controls the power of the first heating device to P7, setting: P7=p1×{1+α1×lg[3×(FY+WY-u0)] / lg4}; and controls the power of the second heating device to P8, setting: P8=0; When the heating mode is no heating, the control unit controls the power of the first heating device and the second heating device to P9, setting P9=0; Among them, p1 is the first preset heating power, p2 is the second preset heating power, α1 is the first preset adjustment coefficient, and α2 is the second preset adjustment coefficient.

5. The temperature control system for new energy vehicle power battery in ultra-low temperature environment according to claim 4 is characterized in that: The freezing analysis unit analyzes the freezing state of the battery pack according to the battery pack ice thickness h0 and the preset thickness h1 collected during the monitoring period, and processes the control process of the power of each heating device according to the analysis result, wherein: If h0≤h1, the freezing analysis unit determines that the freezing state of the battery pack in the current monitoring period is normal; otherwise, the freezing analysis unit determines that the freezing state of the battery pack in the current monitoring period is abnormal; The freezing analysis unit processes the control process of the power of each heating device when the freezing state of the battery pack is abnormal, and sets the processed first preset adjustment coefficient as α1' and the processed second preset adjustment coefficient as α2'.

6. The temperature control system for new energy vehicle power battery in ultra-low temperature environment according to claim 5 is characterized in that: The speed analysis unit analyzes the vehicle driving state according to the vehicle driving speed q0 collected during the monitoring period and the preset driving speed q1, and processes the analysis process of the freezing state of the battery pack according to the analysis result, wherein: If q0≤q1, the speed analysis unit determines that the driving state of the vehicle in the current monitoring period is a normal state, otherwise, the speed analysis unit determines that the driving state of the vehicle in the current monitoring period is a high-speed state; The speed analysis unit processes the analysis process of the frozen state of the battery pack when the vehicle is traveling at a high speed, and sets the processed preset thickness to h2.

7. The temperature control system for new energy vehicle power battery in ultra-low temperature environment according to claim 1, characterized in that: It also includes an early warning module, which is used to warn the user of thermal runaway according to the temperature rise rate of the single battery collected during the management period; the early warning module includes a temperature rise monitoring unit, which is used to analyze the abnormality of the temperature rise rate of the single battery during the management period according to the temperature rise rate of the single battery collected during the management period and the preset temperature rise rate s0, wherein: If si≤s1, the temperature rise monitoring unit determines that the temperature rise rate of the i-th single battery is normal, otherwise, the temperature rise monitoring unit determines that the temperature rise rate of the i-th single battery is abnormal; The temperature rise monitoring unit is also used to calculate the temperature rise uniformity coefficient Y according to the temperature rise rate of the single battery collected during the management period, where si is the temperature rise rate of the i-th single battery collected during the management period; The warning module also includes a warning unit, which is used to analyze the temperature rise state of the power battery according to the abnormality of the temperature rise rate of the single battery and the temperature rise uniformity coefficient Y within the management period, and to issue a thermal runaway warning to the user according to the analysis result, wherein: If exp[3×(j1 / I)-3]+Y≤L, the early warning unit determines that the temperature rise state of the power battery in the current management cycle is normal, and does not issue a thermal runaway warning to the user; otherwise, the early warning unit determines that the temperature rise state of the power battery in the current management cycle is abnormal, and issues a thermal runaway warning to the user; Wherein, j1 is the number of single cells with abnormal temperature rise rate during the management cycle, and L is the preset temperature rise state threshold.

8. The temperature control system for new energy vehicle power battery in ultra-low temperature environment according to claim 7 is characterized in that: It also includes a thermal insulation analysis module, which is used to analyze the thermal insulation coefficient G of the insulating material according to the collected thickness d0 of the insulating material and the thermal conductivity γ of the insulating material, and sets G=A×(d0 / d1)×(γ / γ1), where A is the proportional index, d1 is the thickness threshold, and γ1 is the thermal conductivity threshold; The thermal insulation analysis module analyzes the thermal insulation performance of the insulating material according to the thermal insulation coefficient G and the thermal insulation coefficient threshold G0. If G≤G0, the thermal insulation analysis module determines that the thermal insulation performance of the insulating material is low insulation. Otherwise, the thermal insulation analysis module determines that the thermal insulation performance of the insulating material is high insulation.

9. The temperature control system for new energy vehicle power battery in ultra-low temperature environment according to claim 8, characterized in that: The attenuation analysis module includes a capacity analysis unit, which is used to analyze the capacity attenuation state according to the battery capacity attenuation rs0 and the preset capacity attenuation rs1 collected during the capacity analysis period, wherein: If rs0≤rs1, the capacity analysis unit determines that the battery capacity attenuation state in the current capacity analysis cycle is a normal state. Otherwise, the capacity analysis unit determines that the battery capacity attenuation state in the current capacity analysis cycle is an abnormal state.

10. The temperature control system for new energy vehicle power battery in ultra-low temperature environment according to claim 9, characterized in that: The attenuation analysis module includes a control processing unit, which processes the power control process of the heating device in the next capacity analysis cycle according to the capacity attenuation state, the thermal insulation performance of the insulation material and the thermal runaway warning result, wherein: When the capacity attenuation state is normal and the thermal insulation performance of the insulating material is low, if r0 / R≤η, the control processing unit sets the second preset heating power to pp1, setting pp1=p2; if r0 / R>η, the control processing unit sets the second preset heating power to pp2, setting pp2=p2×[1-B×(r0 / R-η) 1.5 ]; When the capacity attenuation state is abnormal and the thermal insulation performance of the insulating material is low, if r0 / R≤η, the control processing unit sets the second preset heating power to pp3, and sets pp1=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]}; if r0 / R>η, the control processing unit sets the second preset heating power to pp4, and sets pp4=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]-B×(r0 / R-η) 1.5 }; When the capacity attenuation state is normal and the thermal insulation performance of the insulating material is high, if r0 / R≤η, the control processing unit sets the second preset heating power to pp5, setting pp5=p2; if r0 / R>η, the control processing unit sets the second preset heating power to pp6, setting pp6=p2×[1-(r0 / R-η) 1.5 ]; When the capacity attenuation state is abnormal and the thermal insulation performance of the insulating material is high, if r0 / R≤η, the control processing unit sets the second preset heating power to pp7, setting pp7=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]}; if r0 / R>η, the control processing unit sets the second preset heating power to pp8, setting pp8=p2×{1-lg[(rs0-rs1) / (rs0+rs1)+1]-B×(r0 / R-η) 1.5 }; Among them, r0 is the number of management cycles for providing thermal runaway warning to users within the capacity analysis cycle, R is the number of management cycles within the capacity analysis cycle, η is the preset abnormal ratio, and B is the preset adjustment ratio coefficient.

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