A temperature detection method and device of a power battery

Abstract

The application relates to the battery detection technical field and provides a temperature detection method and device for a power battery. The method comprises the following steps: acquiring a current vehicle state parameter of a target vehicle; determining a temperature index corresponding to the current vehicle state parameter based on a preset mapping relationship between the vehicle state parameter and the temperature index of the power battery; acquiring a current battery temperature of the power battery; judging whether the current battery temperature meets each temperature index, and generating a temperature detection result according to all judgment results. The application determines more reliable and detailed temperature indexes for detecting the current battery temperature through the current vehicle state parameter, the temperature indexes are adjusted correspondingly along with the vehicle state parameter, the temperature indexes are no longer kept constant, the current battery temperature can be sensitively fed back whether the current battery temperature is normal, and a more valuable temperature detection result is generated, so that temperature abnormalities can be timely reminded.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery detection, and in particular to a temperature detection method and device for a power battery. BACKGROUND

[0002] New energy vehicles have become the main trend of current vehicle development. In the research of various technologies of new energy vehicles, the safety of power batteries is the focus of users. The power battery is composed of power battery monomers through series connection, parallel connection, mixed connection and the like to form a battery pack to provide power for new energy vehicles. The power battery has hidden dangers such as aging and bulging. In addition, when a new energy vehicle carrying a power battery collides, the power battery may be extruded to deform, and then cause the power battery to burn or explode, resulting in secondary accidents.

[0003] At present, the safety detection of the power battery focuses on whether the battery monomer is normally charged and discharged, and the research on the physical state of the battery itself is relatively rough. Taking temperature detection as an example, a temperature sensor is arranged on the power battery for each battery monomer, and whether the battery monomer is in a normal temperature range is determined according to the temperature sensor. However, the normal temperature range used for judgment here is a constant amount, and it cannot sensitively perceive whether the battery temperature is normal in a specific scene, and there is a certain hysteresis, and the reference value for battery safety is low.

[0004] Therefore, how to provide a solution to the above technical problems is a problem that needs to be solved by the technical personnel in the field at present. SUMMARY

[0005] Therefore, the embodiments of the present application provide a temperature detection method and device for a power battery to solve the problem of insufficient sensitivity of temperature detection in the prior art.

[0006] In a first aspect, the embodiments of the present application provide a temperature detection method for a power battery, comprising:

[0007] obtaining a current vehicle state parameter of a target vehicle; the vehicle state parameter includes multiple types of environmental temperature, working condition of the power battery, health degree of the power battery, current of each battery monomer in the power battery, and voltage of each battery monomer;

[0008] determining a temperature index corresponding to the current vehicle state parameter based on a preset mapping relationship between the vehicle state parameter and the temperature index; the temperature index includes multiple types of minimum temperature, maximum temperature, maximum temperature difference, maximum temperature variance, and average temperature interval;

[0009] obtaining a current battery temperature of the power battery;

[0010] determine whether the current battery temperature meets each temperature index, and generate a temperature detection result according to all the determination results.

[0011] In a second aspect, the application provides a temperature detection device for a power battery, comprising:

[0012] The first obtaining module is configured to obtain a current vehicle state parameter of the target vehicle, wherein the vehicle state parameter comprises multiple types of parameters, such as an ambient temperature, a working condition of the power battery, a health degree of the power battery, a current of each battery monomer in the power battery, and a voltage of each battery monomer.

[0013] The index determining module is configured to determine the temperature index corresponding to the current vehicle state parameter based on a preset mapping relationship between the vehicle state parameter and the temperature index of the power battery, wherein the temperature index comprises multiple types of indexes, such as a minimum temperature, a maximum temperature, a maximum temperature difference, a maximum temperature variance, and an average temperature interval.

[0014] The second obtaining module is configured to obtain a current battery temperature of the power battery.

[0015] The determining module is configured to determine whether the current battery temperature meets each temperature index, and generate a temperature detection result according to all the determination results.

[0016] In a third aspect, the application provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above method when executing the computer program.

[0017] In a fourth aspect, the application provides a computer readable storage medium, which stores a computer program, wherein the computer program is executable on a processor to implement the steps of the above method.

[0018] Compared with the prior art, the embodiments of the application have at least the following beneficial effects: the embodiments of the application determine more reliable and detailed temperature indexes for detecting the current battery temperature through the current vehicle state parameter, the temperature indexes are adjusted according to the vehicle state parameter, and the temperature indexes are no longer constant, so that the current battery temperature can be sensitively fed back to determine whether the current battery temperature is normal, and a more valuable temperature detection result is generated to timely remind the temperature abnormality. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0020] Figure 1 is a scene schematic diagram of an application scenario of an embodiment of the present application.

[0021] Figure 2 is a flow schematic diagram of a temperature detection method of a power battery provided by an embodiment of the present application.

[0022] Figure 3 is a structural schematic diagram of a temperature detection device of a power battery provided by an embodiment of the present application.

[0023] Figure 4 is a structural schematic diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0024] In the following description, specific details are set forth in order to provide a thorough understanding of embodiments of the application. However, persons having ordinary skill in the art will appreciate that embodiments of the application can be practiced without the specific details, and that the scope of the application is not limited to the embodiments described herein. In other instances, well-known structures and functions are not described in detail in order to avoid obscuring the description of the application.

[0025] A temperature detection method and device of a power battery according to an embodiment of the present application will be described in detail below with reference to the accompanying drawings.

[0026] Figure 1 is a scene schematic diagram of an application scenario of an embodiment of the present application. The application scenario can include a first terminal device 101, a second terminal device 102, a third terminal device 103, a server 104 and a network 105.

[0027] The first terminal device 101 can be hardware or software. When the first terminal device 101 is hardware, it can be various vehicle systems with a display screen and supporting communication with the server 104; when the first terminal device 101 is software, it can be installed in an electronic device as described above. The first terminal device 101 can be implemented as multiple software or software modules, or as a single software or software module, and the present application is not limited thereto. Further, the first terminal device 101 can have various applications installed thereon, such as data processing applications, instant messaging tools, social platform software, search applications, shopping applications, etc.

[0028] The second terminal device 102 can be hardware or software. When the second terminal device 102 is hardware, it can be various vehicle systems with a display screen and supporting communication with the server 104; when the second terminal device 102 is software, it can be installed in an electronic device as described above. The second terminal device 102 can be implemented as multiple software or software modules, or as a single software or software module, and the embodiments of the present application do not limit this. Further, various applications can be installed on the second terminal device 102, such as data processing applications, instant messaging tools, social platform software, search applications, shopping applications, etc.

[0029] The third terminal device 103 can be hardware or software. When the third terminal device 103 is hardware, it can be various vehicle systems with a display screen and supporting communication with the server 104; when the third terminal device 103 is software, it can be installed in an electronic device as described above. The third terminal device 103 can be implemented as multiple software or software modules, or as a single software or software module, and the embodiments of the present application do not limit this. Further, various applications can be installed on the third terminal device 103, such as data processing applications, instant messaging tools, social platform software, search applications, shopping applications, etc.

[0030] The server 104 can be a server that provides various services, for example, a background server that receives requests sent by a terminal device that establishes a communication connection therewith. The background server can receive and analyze the request sent by the terminal device, etc., and generate a processing result. The server 104 can be a server, a server cluster composed of several servers, or a cloud computing service center, and the embodiments of the present application do not limit this.

[0031] It should be noted that the server 104 can be hardware or software. When the server 104 is hardware, it can be various electronic devices that provide various services for the first terminal device 101, the second terminal device 102, and the third terminal device 103. When the server 104 is software, it can be multiple software or software modules that provide various services for the first terminal device 101, the second terminal device 102, and the third terminal device 103, or a single software or software module that provides various services for the first terminal device 101, the second terminal device 102, and the third terminal device 103, and the embodiments of the present application do not limit this.

[0032] The network 105 can be a wired network using coaxial cables, twisted-pair cables, and optical fibers, or a wireless network using Bluetooth, Near Field Communication (NFC), Infrared, etc., without limitation.

[0033] It should be noted that the specific types, quantities, and combinations of the first terminal device 101, the second terminal device 102, the third terminal device 103, the server 104, and the network 105 can be adjusted according to actual requirements of an application scenario, without limitation.

[0034] Figure 2 FIG. 1 is a flowchart of a temperature detection method of a power battery according to an embodiment of the present application. Figure 2 The temperature detection method of the power battery can be executed by Figure 1 a first terminal device, a second terminal device, a third terminal device, or a server. As shown in FIG. 1, the temperature detection method of the power battery includes the following steps. Figure 2

[0035] S201: Obtain a current vehicle state parameter of a target vehicle; the vehicle state parameter includes multiple types of parameters such as an ambient temperature, a working condition of the power battery, a health degree of the power battery, a current of each battery monomer in the power battery, and a voltage of each battery monomer.

[0036] S202: Determine a temperature index corresponding to the current vehicle state parameter based on a preset mapping relationship between the vehicle state parameter and the temperature index of the power battery; the temperature index includes multiple types of indexes such as a minimum temperature, a maximum temperature, a maximum temperature difference, a maximum temperature variance, and an average temperature interval.

[0037] S203: Obtain a current battery temperature of the power battery.

[0038] S204: Determine whether the current battery temperature meets each temperature index, and generate a temperature detection result according to all determination results.

[0039] ​Specifically, the current vehicle state parameters of the target vehicle include ambient temperature, working condition of the power battery, health degree of the power battery, current of each battery monomer in the power battery, and voltage of each battery monomer. Taking the current vehicle state parameters including ambient temperature, working condition of the power battery, health degree of the power battery, current of each battery monomer in the power battery, and voltage of each battery monomer as an example, a set of current vehicle state parameters obtained by executing step S201 once can be recorded as STA_0=[TA_0,ST_BA_0,SOH_0,I_0,U_0], wherein STA_0 is the current vehicle state parameter, TA_0, ST_BA_0, and SOH_0 are ambient temperature, working condition of the power battery, and health degree of the power battery obtained this time, respectively, I_0 and U_0 are current array and voltage array of all battery monomers in the power battery, respectively, I_0=[i1_0,i2_0,…,in_0], U_0=[u1_0,u2_0,…,un_0], n is the total number of battery monomers in the power battery of the target vehicle, i1_0 to in_0 are currents of the 1st battery monomer to the nth battery monomer, respectively, and u1_0 to un_0 are voltages of the 1st battery monomer to the nth battery monomer, respectively.

[0040] Correspondingly, the temperature indicators include minimum temperature, maximum temperature, maximum temperature difference, maximum temperature variance, and average temperature interval. Taking the temperature indicators including minimum temperature, maximum temperature, maximum temperature difference, maximum temperature variance, and average temperature interval as an example, a set of temperature indicators obtained by executing step S202 once can be recorded as:

[0041] T_index=[T_min_index,T_max_index,Delta_max_index,Var_max_index,Ave_max_index,Ave_min_index];

[0042] Wherein T_index is the temperature indicator, T_min_index, T_max_index, Delta_max_index, and Var_max_index are minimum temperature, maximum temperature, maximum temperature difference, and maximum temperature variance, respectively, and Ave_max_index and Ave_min_index are right end point and left end point of the average temperature interval, respectively.

[0043] Specifically, still taking the power battery including n battery monomers as an example, the current battery temperature T_ac of the power battery is T_ac=[T1_ac,T2_ac,…,Tn_ac], T1_ac to Tn_ac are actual temperatures of the 1st battery monomer to the nth battery monomer, respectively, and the indicator meanings of the parameters in the temperature indicators are as follows:

[0044] Minimum temperature: the minimum value of the actual temperatures of all battery cells of the current power battery should not be less than the minimum temperature, i.e., MIN(T1_ac, T2_ac, …, Tn_ac) ≥ T_min_index, MIN is the minimum value operation;

[0045] Maximum temperature: the maximum value of the actual temperatures of all battery cells of the current power battery should not be greater than the maximum temperature, i.e., MAX(T1_ac, T2_ac, …, Tn_ac) ≤ T_max_index, MAX is the maximum value operation;

[0046] Maximum temperature difference: the difference between the maximum value and the minimum value of the actual temperatures of all battery cells of the current power battery should not be greater than the maximum temperature difference, i.e., MAX(T1_ac, T2_ac, …, Tn_ac) - MIN(T1_ac, T2_ac, …, Tn_ac) ≤ Delta_max_index;

[0047] Temperature variance maximum value: the variance of the actual temperatures of all battery cells of the current power battery should not be greater than the temperature variance maximum value, i.e., STDEVP(T1_ac, T2_ac, …, Tn_ac) ≤ Var_max_index, STDEVP is the variance operation;

[0048] Average temperature interval: the average value of the actual temperatures of all battery cells of the current power battery should be within the average temperature interval, i.e.,

[0049] Ave_min_index ≤ AVE(T1_ac, T2_ac, …, Tn_ac) ≤ Ave_max_index;

[0050] AVE is the average value calculation.

[0051] It can be understood that the preset mapping relationship mentioned in step S202 can be represented as T_index = f(STA), where STA is a general vehicle state parameter, and STA = STA_0, which determines the current temperature index T_index_0 = f(STA_0) corresponding to the current vehicle state parameter STA_0 under the preset mapping relationship. Once the vehicle state parameter changes, the corresponding temperature index will also change.

[0052] It can be understood that the current vehicle state parameter will affect the current battery temperature of the power battery, and the current battery temperature of the power battery under different vehicle state parameters may be different, for example, the battery temperature corresponding to the environment temperature of 25° is T1, and the battery temperature corresponding to the environment temperature of 30° is T2. The battery temperature is affected by the heat conduction of the environment temperature, and in general cases, T2 is obviously higher than T1, but it does not mean that the battery of T2 is in an over-temperature state. According to the prior art, if only one constant temperature range T01-T02 is set as a temperature index, T1 is in the constant temperature range, if T2 is greater than T02, the power battery will be judged as an over-temperature abnormality when the environment temperature is 30°, but in fact, the power battery is only disturbed by the environment temperature, and there is no abnormality in essence. Considering that the influencing factors affect the battery temperature of the power battery, only the fixed temperature constant standard is used to determine the battery temperature, which is easy to misjudge and has poor accuracy. The embodiment adjusts the determination standard of the constant battery temperature to the temperature index which can be selected according to the current vehicle state parameter, so as to improve the accuracy of the determination.

[0053] In step S201, the environment temperature is obtained by a temperature sensor arranged on the vehicle, the working condition of the power battery includes one or more of a charging working condition, a discharging working condition, a static working condition, an on-off switching working condition, and an unexpected working condition, the unexpected working condition corresponds to a preset event of the target vehicle, and the working condition, the health degree (SOH) of the power battery, and the current and voltage of each battery cell can be obtained by the BMS (Battery Management System).

[0054] In step S202, when the temperature index is obtained, the mapping table corresponding to the vehicle state parameter-temperature index can be looked up, the mapping table is determined according to the standard data generated by the test vehicle, or a neural network training model obtained by training the standard data as a standard training sample can be selected to realize, specifically, based on the preset mapping relationship between the vehicle state parameter and the temperature index of the power battery, the process of determining the temperature index corresponding to the current vehicle state parameter includes: inputting the current vehicle state parameter into the trained neural network model to obtain the corresponding temperature index of the power battery;

[0055] The neural network model is determined by training a plurality of standard training samples, and is used to reflect the preset mapping relationship between the vehicle state parameter and the temperature index of the power battery.

[0056] Each standard training sample includes a standard vehicle state parameter and a standard temperature index of the power battery corresponding to the standard vehicle state parameter.

[0057] The temperature index is used to evaluate the battery temperature of a group of battery monomers of the power battery. Further, after determining the temperature index, the temperature index can be corrected according to other determined real-vehicle temperature examples of the test vehicle in a safe and normal state, so as to reduce the influence of insufficient representativeness of test data in ideal conditions. The method of the embodiment further comprises:

[0058] Obtaining the vehicle state parameters and the battery temperature uploaded by the test vehicle as reference information;

[0059] Based on the preset mapping relationship, determining the temperature index corresponding to the vehicle state parameter in the reference information as the reference temperature index;

[0060] Determining the actual index value of the temperature index based on the battery temperature in the reference information;

[0061] Correcting the reference temperature index by a correction formula, and updating the preset mapping relationship based on the corrected reference temperature index and the reference information, the correction formula comprising:

[0062] T_s1=a×T_s0+(1-a)×T_r;

[0063] Wherein, T_s1 is one end point value of the corrected reference temperature index, T_s0 is the end point value of the reference temperature index before correction, T_r is the actual index value corresponding to the end point value, and a is a correction coefficient, wherein a takes a value between 0 and 1, and usually can be selected as a value between 0.85 and 0.98. T_s0 can be an end point value of a certain interval index in the reference temperature index, for example, the left end point or the right end point of the average temperature interval. When a certain index in the reference temperature index is not an interval, only a specific value, the index can be regarded as a closed interval with the left end point and the right end point being the specific value, so the specific value is also regarded as an end point of the closed interval. Therefore, T_s0 can also be the lowest temperature or the highest temperature or the maximum temperature difference or the maximum temperature variance. At this time, T_s1, T_s0 and T_r all belong to the same end point of the same reference temperature index in different stages or processes.

[0064] Step S203 obtains the current battery temperature of the power battery, specifically obtains the current battery temperature of each battery monomer in the power battery, and further judges whether the current battery temperature meets each temperature index. For example, the current battery temperature of the power battery is an array T_ac=[T1_ac,T2_ac,…,Tn_ac].

[0065] When the step S204 judges whether the battery temperature meets each temperature index, the actual index quantity of the current battery temperature is calculated first, for example, the minimum temperature T_min_ac = MIN(T1_ac, T2_ac, …, Tn_ac), the maximum temperature T_max_ac = MAX(T1_ac, T2_ac, …, Tn_ac), the maximum temperature difference Delta_max_ac = T_max_ac - T_min_ac, the average temperature is the average of the array, and the variance is the variance of the array. After the actual index quantity is calculated, whether the temperature index is met is analyzed, for example, when the temperature index is the minimum temperature, the index requirement is T_min_ac ≥ T_min_index, and T_min_index is the index of the minimum temperature determined by the vehicle state parameter in the step S202.

[0066] Similarly, when the temperature index is the maximum temperature, the index requirement is T_max_ac ≤ T_max_index, and T_max_index is the index of the maximum temperature determined by the vehicle state parameter in the step S202; when the temperature index is the maximum temperature difference, the index requirement is Delta_max_ac ≤ Delta_max_index, and Delta_max_index is the index of the maximum temperature difference determined by the vehicle state parameter in the step S202; when the temperature index is the maximum temperature variance, the index requirement is that the temperature variance of the actual index quantity is less than the maximum temperature variance; when the temperature index is the average temperature interval, the index requirement is that the average temperature of the actual index quantity is in the calibrated average temperature interval.

[0067] It can be understood that the current vehicle state parameter and the temperature index in the embodiment are only examples, and the specific parameter selection and the number selection can be adjusted according to the actual situation, which is not limited here.

[0068] The step S204 generates the temperature detection result according to whether the current battery temperature meets each temperature index. Since the temperature index is determined according to the current vehicle state parameter, the current battery temperature can be more accurately judged to be normal or not. Further, the step S204 generates the temperature detection result according to all the judgment results, including:

[0069] The number of temperature indexes that are not met by the current battery temperature is counted as the number of abnormal temperature indexes;

[0070] The alarm level is determined according to the number of abnormal temperature indexes, and the alarm level is positively correlated with the number of abnormal temperature indexes;

[0071] The temperature detection result is generated in combination with all the judgment results, the number of abnormal temperature indexes and the alarm level;

[0072] According to the alarm level, corresponding alarm measures are executed.

[0073] For example, the current battery temperature neither meets the minimum temperature index requirement nor meets the average temperature interval index requirement, and meets other index requirements, the number of abnormal temperature indexes is 2.

[0074] It can be understood that the more the number of abnormal temperature indexes, the higher the alarm level, that is, the greater the probability of the current power battery abnormality and the higher the danger level. The alarm level can be equal to the number of abnormal temperature indexes, or the alarm level can be determined according to the weighted sum result of the weight of each temperature index. The alarm levels from low to high can be in turn set as maintenance prompt, maintenance reminder, maintenance alarm, danger alarm, etc., and the corresponding alarm measures from low to high, for example, the alarm measure of the maintenance prompt is only to display the prompt information of "battery temperature abnormal, please maintain" on the display screen; the alarm measure of the maintenance reminder is to send the prompt information of "battery temperature abnormal, please maintain" through the display screen, voice broadcast and mobile phone APP, and can also stop the work of the abnormal battery monomer; the alarm measure of the maintenance alarm is to stop the work of the entire power battery on the basis of the maintenance reminder; the alarm measure of the danger alarm is to set a larger notification range on the basis of the maintenance alarm, for example, to play the prompt information of "battery temperature abnormal, please away" through the external sound, etc. The specific setting of the alarm level and the alarm measure can be carried out according to the actual demand and the actual working condition, which is not limited here.

[0075] It can be understood that in addition to being determined according to the current vehicle state, the state of the power battery will also be affected by heat accumulation. After a period of heat accumulation, the original temperature index is no longer applicable, and the temperature index needs to be corrected again. Generally, the correction direction here is to correct the temperature index more strictly, for example, to correct the maximum temperature variance to a smaller value, to correct the maximum temperature difference to a smaller value, to narrow the average temperature interval, etc. Therefore, the method of the embodiment further comprises:

[0076] When the alarm level is not less than the preset level, the temperature index is corrected according to the heat accumulation of the power battery, and the step of judging whether the current battery temperature meets each temperature index is executed;

[0077] The temperature index is corrected according to the heat accumulation of the power battery, comprising:

[0078] According to the current vehicle state parameters, the heat generation of the current power battery and the environmental heat dissipation are determined; and the heat accumulation value of the current battery temperature with time is obtained by subtracting the environmental heat dissipation from the heat generation.

[0079] Based on the heat accumulation value, the maximum temperature variance is reduced, and the maximum temperature difference is reduced.

[0080] Wherein the heat generation of the power battery can be calculated according to the current of the power battery, the voltage of the power battery, and the internal resistance of the power battery, and the environmental heat dissipation, i.e., the heat exchange between the power battery and the environment, can be determined based on the temperature difference between the current battery temperature and the environmental temperature, the air heat conduction coefficient, and other parameters, and can be specifically referred to the theoretical technology of thermal engineering.

[0081] It can be understood that the execution of the method of the embodiment is a continuous cycle, i.e., the actions of steps S201-S204 are continuously executed, wherein steps S201 and S203 are performed at a higher frequency, and if the result of step S201 or S203 in the previous execution is the same as the result of the current execution, steps S202 and S204 do not need to be repeated. However, the execution of high-frequency actions inevitably consumes a large amount of memory resources, and according to different situations, different monitoring frequencies can be set to flexibly manage the temperature detection method. In the case of a lower probability of temperature abnormality, a lower monitoring frequency is allowed, and in the case of a higher probability of temperature abnormality, the monitoring frequency must be set to a higher value to avoid insufficient detection in time. Specifically, the working conditions include charging working condition, discharging working condition, static working condition, power-on / off switching working condition, and unexpected working condition, the unexpected working condition corresponds to a preset event occurring in the target vehicle; before obtaining the current battery temperature of the power battery, the method further includes:

[0082] determining the monitoring frequency according to the current working condition;

[0083] The process of obtaining the current battery temperature of the power battery includes:

[0084] obtaining the current battery temperature of the power battery according to the monitoring frequency;

[0085] The process of determining whether the current battery temperature meets the temperature indicators and generating a temperature detection result according to all the determination results includes:

[0086] determining whether the current battery temperature meets the temperature indicators according to the monitoring frequency, and generating a temperature detection result according to all the determination results.

[0087] Among them, the monitoring frequency of the static working condition is the lowest, the monitoring frequency of the charging working condition and the discharging working condition is the second, and the monitoring frequency of the power-on / off switching working condition and the unexpected working condition is the highest. The power-on / off switching working condition includes switching from power-off to power-on or from power-on to power-off, and the state of the power battery changes significantly, so the change process temperature needs to be monitored; the unexpected working condition corresponds to a preset event occurring in the target vehicle, which may affect the state of the power battery, for example, a collision event. The collision event may cause the internal structure of the power battery to deform, thereby causing a short circuit and rapid heating of the battery, so a higher monitoring frequency must be used to determine whether there is a temperature abnormality to ensure the safety of the battery.

[0088] Further monitoring frequency can adjust the monitoring frequency according to the change of the number of abnormal temperature indicators, and the method of the embodiment further comprises:

[0089] When the number of abnormal temperature indicators in the continuous temperature detection results is less than the preset value, and the change trend of the number of abnormal temperature indicators in the continuous temperature detection results is not rising, the monitoring frequency is lowered; the number of abnormal temperature indicators is the number of temperature indicators that do not meet the current battery temperature;

[0090] When the number of abnormal temperature indicators in the continuous temperature detection results is not less than the preset value, or the change trend of the number of abnormal temperature indicators in the continuous temperature detection results is rising, the monitoring frequency is raised.

[0091] By flexibly adjusting the monitoring frequency, the occupation of the computing resources and the memory resources by the method of the embodiment is reduced while ensuring that the temperature hazards of the power battery are not missed.

[0092] The embodiment of the application determines more reliable and detailed temperature indicators for detecting the current battery temperature through the current vehicle state parameters. The temperature indicators are adjusted according to the vehicle state parameters and no longer remain constant. The temperature indicators can sensitively feedback whether the current battery temperature is normal and generate more valuable temperature detection results to timely remind the temperature abnormality.

[0093] All the optional technical solutions described above can be combined to form optional embodiments of the application, which will not be described one by one. It should be understood that the size of the serial number of each step in the above embodiments does not mean the execution order, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the application.

[0094] The following is a device embodiment of the application, which can be used to execute the method embodiments of the application. For details not disclosed in the device embodiments of the application, please refer to the method embodiments of the application.

[0095] Figure 3 A temperature detection device for a power battery is provided in the embodiment of the application, as shown in FIG. 3, which comprises:

[0096] The first acquisition module 301 is configured to acquire the current vehicle state parameters of the target vehicle. The vehicle state parameters include multiple types of environmental temperature, working condition of the power battery, health degree of the power battery, current of each battery monomer in the power battery, and voltage of each battery monomer.

[0097] The index determination module 302 is configured to determine a temperature index corresponding to the current vehicle state parameter based on a preset mapping relationship between the vehicle state parameter and the temperature index of the power battery; the temperature index includes multiple types of temperature indexes, such as a minimum temperature, a maximum temperature, a maximum temperature difference, a maximum temperature variance, and an average temperature interval;

[0098] The second acquisition module 303 is configured to acquire a current battery temperature of the power battery.

[0099] The determination module 304 is configured to determine whether the current battery temperature meets each temperature index, and generate a temperature detection result according to all determination results.

[0100] The embodiment of the application determines more reliable and detailed temperature indexes for detecting the current battery temperature through the current vehicle state parameter, the temperature indexes are adjusted correspondingly with the vehicle state parameter, and the temperature indexes are no longer constant, so that the current battery temperature can be sensitively fed back to determine whether the current battery temperature is normal, and a more valuable temperature detection result is generated to timely remind the temperature abnormality.

[0101] In an exemplary embodiment, the working conditions include a charging working condition, a discharging working condition, a static working condition, an on-off switching working condition, and an unexpected working condition; the unexpected working condition corresponds to a preset event occurring to the target vehicle; the device further includes a frequency determination module 305 configured to:

[0102] determine a monitoring frequency according to the current working condition;

[0103] The process in which the second acquisition module 303 acquires the current battery temperature of the power battery includes:

[0104] acquire the current battery temperature of the power battery according to the monitoring frequency;

[0105] The process in which the determination module 304 determines whether the current battery temperature meets each temperature index, and generates a temperature detection result according to all determination results includes:

[0106] determine whether the current battery temperature meets each temperature index according to the monitoring frequency, and generate a temperature detection result according to all determination results.

[0107] In an exemplary embodiment, the frequency determination module 305 is further configured to:

[0108] when the number of abnormal temperature indexes in the continuous multiple temperature detection results is less than a preset value, and the change trend of the number of abnormal temperature indexes in the continuous multiple temperature detection results is not rising, the monitoring frequency is lowered; the number of abnormal temperature indexes is the number of temperature indexes that are not met by the current battery temperature.

[0109] When the number of abnormal temperature indicators in the continuous temperature detection results is not less than the preset value, or the trend of the number of abnormal temperature indicators in the continuous temperature detection results is rising, the monitoring frequency is increased.

[0110] In an exemplary embodiment, based on the preset mapping relationship between the vehicle state parameter and the temperature indicator of the power battery, the process of determining the temperature indicator corresponding to the current vehicle state parameter comprises:

[0111] inputting the current vehicle state parameter into the trained neural network model to obtain the temperature indicator of the corresponding power battery;

[0112] The neural network model is determined by training a plurality of standard training samples, and is used to reflect the preset mapping relationship between the vehicle state parameter and the temperature indicator of the power battery.

[0113] Each standard training sample includes a standard vehicle state parameter and a standard temperature indicator of the power battery corresponding to the standard vehicle state parameter.

[0114] In an exemplary embodiment, the index determination module 302 is further configured to:

[0115] obtain the vehicle state parameter and the battery temperature uploaded by the test vehicle as reference information;

[0116] determine the temperature indicator corresponding to the vehicle state parameter in the reference information as a reference temperature indicator based on the preset mapping relationship;

[0117] determine the actual indicator value of the temperature indicator based on the battery temperature in the reference information;

[0118] correct the reference temperature indicator by a correction formula, and update the preset mapping relationship based on the corrected reference temperature indicator and the reference information, the correction formula comprising:

[0119] T_s1=a×T_s0+(1-a)×T_r;

[0120] wherein T_s1 is an end point value of the corrected reference temperature indicator, T_s0 is an end point value of the uncorrected reference temperature indicator, T_r is an actual indicator value corresponding to the end point value, and a is a correction coefficient.

[0121] In an exemplary embodiment, the process of generating the temperature detection result according to all the judgment results comprises:

[0122] counting the number of temperature indicators that are not satisfied by the current battery temperature as the number of abnormal temperature indicators;

[0123] determining the alarm level according to the number of abnormal temperature indicators, the alarm level being positively correlated with the number of abnormal temperature indicators;

[0124] generate a temperature detection result according to all the judgment results, the number of abnormal temperature indexes and the alarm level;

[0125] According to the alarm level, a corresponding alarm measure is performed.

[0126] In an exemplary embodiment, the index determination module 302 is further configured to:

[0127] When the alarm level is not less than a preset level, the temperature index is corrected according to the heat accumulation of the power battery, and the step of judging whether the current battery temperature meets each temperature index is performed;

[0128] The temperature index is corrected according to the heat accumulation of the power battery, including:

[0129] According to the current vehicle state parameter, the heat generation of the current power battery and the environmental heat dissipation are determined, and the heat accumulation value of the current battery temperature with time is obtained by subtracting the heat generation from the environmental heat dissipation;

[0130] Based on the heat accumulation value, the maximum temperature variance is reduced, and the maximum temperature difference is reduced.

[0131] Figure 4 is a schematic diagram of an electronic device 4 provided by an embodiment of the present application. As shown in Figure 4 The electronic device 4 of this embodiment includes a processor 401, a memory 402, and a computer program 403 stored in the memory 402 and executable on the processor 401. The processor 401 implements the steps in each of the above method embodiments when executing the computer program 403. Alternatively, the processor 401 implements the functions of each module / unit in each of the above device embodiments when executing the computer program 403.

[0132] The electronic device 4 can be a desktop computer, a notebook computer, a palm computer, a cloud server, and the like. The electronic device 4 can include but is not limited to the processor 401 and the memory 402. Those skilled in the art can understand that Figure 4 The electronic device 4 is only an example and does not constitute a limitation on the electronic device 4, and can include more or fewer components or different components than those shown.

[0133] The processor 401 can be a central processing unit (CPU), and can also be other processors, such as an application-specific integrated circuit (ASIC), a programmable logic device (PLD) or a field programmable gate array (FPGA).

[0134] other programmable logic device, discrete gate or transistor logic, discrete hardware components, or the like.

[0135] The memory 402 can be an internal storage unit of the electronic device 4, for example, a hard disk or a memory of the electronic device 4. The memory 402 can also be an external storage device of the electronic device 4, for example, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, or the like equipped on the electronic device 4. The memory 402 can also include both the internal storage unit and the external storage device of the electronic device 4. The memory 402 is used to store computer programs and other programs and data required by the electronic device.

[0136] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above functional units and modules is exemplified, and in actual application, the above functions can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0137] The integrated modules / units, if implemented in the form of software functional units and sold or used as independent products, can be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the above-mentioned embodiment methods can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer readable storage medium. The computer program can be executed by a processor to implement the steps of the above-mentioned various method embodiments. The computer program can include computer program code, which can be in the form of source code, object code, executable files, or some intermediate forms. The computer readable storage medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer readable storage medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer readable storage medium does not include electric carrier signals and telecommunication signals.

[0138] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A method for detecting the temperature of a power battery, characterized in that, include: Obtain the current vehicle status parameters of the target vehicle; the vehicle status parameters include multiple parameters such as ambient temperature, power battery operating condition, power battery health, current of each battery cell in the power battery, and voltage of each battery cell; the operating condition includes charging condition, discharging condition, stationary condition, power-on / off switching condition, and unexpected condition, and the unexpected condition corresponds to a preset event occurring in the target vehicle; Based on the preset mapping relationship between the vehicle state parameters and the temperature index of the power battery, the temperature index corresponding to the current vehicle state parameters is determined; the temperature index includes multiple values ​​among the following: minimum temperature, maximum temperature, maximum temperature difference, maximum temperature variance, and average temperature range. Determine the monitoring frequency based on the current operating conditions; The current battery temperature of the power battery is obtained according to the monitoring frequency. Determine whether the current battery temperature meets all the temperature indicators, and generate a temperature detection result based on all the determination results, including: determining whether the current battery temperature meets all the temperature indicators based on the monitoring frequency, and generating a temperature detection result based on all the determination results.

2. The method according to claim 1, characterized in that, Also includes: If the number of abnormal temperature indicators in multiple consecutive temperature detection results is less than a preset value, and the trend of the number of abnormal temperature indicators in multiple consecutive temperature detection results is not upward, then the monitoring frequency is reduced; the number of abnormal temperature indicators is the number of temperature indicators that the current battery temperature does not meet. If the number of abnormal temperature indicators in multiple consecutive temperature detection results is not less than a preset value, or if the number of abnormal temperature indicators in multiple consecutive temperature detection results shows an upward trend, then the monitoring frequency is increased.

3. The method according to claim 1, characterized in that, The process of determining the temperature index corresponding to the current vehicle state parameters based on the preset mapping relationship between the vehicle state parameters and the temperature index of the power battery includes: The current vehicle state parameters are input into the trained neural network model to obtain the corresponding temperature index of the power battery; The neural network model is determined through training on multiple standard training samples and is used to reflect the preset mapping relationship between the vehicle state parameters and the temperature index. Each of the standard training samples includes a standard vehicle state parameter and a standard temperature index of the power battery corresponding to the standard vehicle state parameter.

4. The method according to claim 1, characterized in that, Also includes: Obtain the vehicle status parameters and battery temperature uploaded by the test vehicle as reference information; Based on the preset mapping relationship, the temperature index corresponding to the vehicle state parameter in the reference information is determined as the reference temperature index. The actual value of the temperature index is determined based on the battery temperature in the reference information. The reference temperature index is corrected using a correction formula, and the preset mapping relationship is updated based on the corrected reference temperature index and the reference information. The correction formula includes: T_s1 = a × T_s0 + (1-a) × T_r; Wherein, T_s1 is an endpoint value of the corrected reference temperature index, T_s0 is the endpoint value of the reference temperature index before correction, T_r is the actual index value corresponding to the endpoint value, and a is the correction coefficient.

5. The method according to any one of claims 1 to 4, characterized in that, The process of generating temperature detection results based on all judgment results includes: The number of battery temperatures that do not meet the temperature index is recorded as the number of abnormal temperature indices. The alarm level is determined based on the number of abnormal temperature indicators, and the alarm level is positively correlated with the number of abnormal temperature indicators. A temperature detection result is generated by combining all judgment results, the number of abnormal temperature indicators, and the alarm level. Perform the corresponding alarm measures according to the alarm level.

6. The method according to claim 5, characterized in that, Also includes: When the alarm level is not less than the preset level, the temperature index is corrected according to the heat accumulation of the power battery, and the step of determining whether the current battery temperature meets the various temperature indexes is executed. The temperature index is corrected based on the heat accumulation of the power battery, including: Based on the current vehicle status parameters, determine the current heat generation of the power battery and the ambient heat dissipation; calculate the difference between the heat generation and the ambient heat dissipation to obtain the cumulative heat value of the current battery temperature over time. Based on the accumulated heat value, the maximum temperature variance is reduced, thereby reducing the maximum temperature difference.

7. A temperature detection device for a power battery, characterized in that, include: The first acquisition module is used to acquire the current vehicle status parameters of the target vehicle; the vehicle status parameters include multiple parameters such as ambient temperature, operating condition of the power battery, health of the power battery, current of each battery cell in the power battery, and voltage of each battery cell; the operating condition includes charging condition, discharging condition, stationary condition, power-on / off switching condition, and accident condition, and the accident condition corresponds to a preset event occurring in the target vehicle. The index determination module is used to determine the temperature index corresponding to the current vehicle state parameters based on a preset mapping relationship between the vehicle state parameters and the temperature index of the power battery; the temperature index includes multiple values ​​such as minimum temperature, maximum temperature, maximum temperature difference, maximum temperature variance, and average temperature range. The frequency determination module is used to determine the monitoring frequency based on the current operating conditions. The second acquisition module is used to acquire the current battery temperature of the power battery according to the monitoring frequency; The judgment module is used to determine whether the current battery temperature meets the various temperature indicators, and generate a temperature detection result based on all judgment results, including: determining whether the current battery temperature meets the various temperature indicators based on the monitoring frequency, and generating a temperature detection result based on all judgment results.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 6.

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