Non-vehicle-mounted new energy vehicle power battery performance online detection method and system

Abstract

The invention discloses a non-vehicle-mounted new energy vehicle power battery performance online detection method and system. A charger and a new energy vehicle are connected through a guide circuit module; performing data acquisition and performance detection on the power battery of the new energy vehicle in the charging preparation stage through an insulation detection module and a BMS communication acquisition module; performing data acquisition and performance detection on the power battery of the new energy vehicle in the charging process stage through an electrical performance acquisition module and a BMS communication acquisition module; performing data acquisition on a power battery of the new energy vehicle in a charging ending stage through the BMS communication acquisition module; according to the obtained battery data, the battery performance is detected and analyzed through the main control module; the data information of the vehicle power battery is displayed through a non-vehicle-mounted externally-connected independent detection system without depending on a vehicle-mounted battery management system (BMS), and meanwhile the vehicle power battery is detected to obtain the detection data.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicle power batteries, and in particular to a method and system for online performance detection of a non-vehicle-mounted new energy vehicle power battery. Background Art

[0002] With the transformation of the global energy structure and the enhancement of environmental awareness, the new energy vehicle industry has flourished, among which new energy vehicles powered by batteries are becoming increasingly popular. As a key core component of new energy vehicles, the performance of batteries is directly related to the overall performance of the vehicle. However, there are many deficiencies in the current understanding of battery performance and working conditions. This situation leads to unreasonable charging and discharging operations of batteries in actual use, which greatly shortens their service life.

[0003] At the same time, the application of bidirectional charging and discharging piles in the field of new energy vehicles is becoming more and more extensive. This trend has put forward higher requirements for the online detection capability of battery charging and discharging performance. However, the existing new energy vehicle power battery detection technology is difficult to meet this demand, and many problems are exposed in the detection process. On the one hand, the detection cannot be comprehensive and follow a unified standard, the accuracy of the obtained data is difficult to guarantee, and some important functions and data cannot even be effectively detected. On the other hand, the existing detection methods have obvious defects: inside the vehicle, although the on-board battery management system (BMS) can perform operations such as parameter collection and health status estimation on the vehicle power battery, its detection technology varies from vehicle manufacturer to vehicle manufacturer, and the evaluation standards lack uniformity, which ultimately leads to a large deviation in the battery test results, and it is difficult to obtain reliable and standard test results to accurately evaluate the battery health status. Outside the vehicle, a battery tester is usually used for offline detection. This method not only cannot continuously and repeatedly measure the same vehicle power battery pack to obtain consistent results, but also because the test process itself is a discharge process, the battery pack after the test must be recharged before it can be measured again, which greatly reduces the accuracy of the test, and the detection is not comprehensive enough, and it is impossible to record and compare important indicators such as insulation status and SOC change curve. In addition, there are certain safety hazards in the detection method of directly operating the battery tester by humans, which brings potential risks to the testers and vehicles. Summary of the invention

[0004] The technical problem to be solved by the present invention is: a new energy vehicle power battery performance detection method and system provided by the present invention can detect the charging and discharging performance and operating status of the new energy vehicle power battery through a non-vehicle-mounted external access method under the bidirectional charging and discharging state, and evaluate and reflect the health of the battery.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: A method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle comprises the following steps: S1. Connect the charger and the new energy vehicle through the pilot circuit module; S2. Performing data collection and performance testing on the power battery of the new energy vehicle in the charging preparation stage through the insulation detection module and the BMS communication acquisition module; S3, collecting data and performing performance testing on the power battery of the new energy vehicle during the charging process through the electrical performance collection module and the BMS communication collection module; S4, collecting data from the power battery of the new energy vehicle at the end of charging through the BMS communication collection module; S5. According to the battery data obtained in steps S2 to S4, the main control module performs detection and analysis on the battery performance.

[0006] In order to solve the above technical problems, another technical solution adopted by the present invention is: A non-vehicle-mounted new energy vehicle power battery performance online detection system includes a main control module, a BMS communication acquisition module, a guide circuit module, an electrical performance acquisition module, an insulation detection module and a display output module; the guide circuit module is respectively connected to the BMS communication acquisition module, the electrical performance acquisition module and the insulation detection module; The main control module is connected to the BMS communication acquisition module, the electrical performance acquisition module, the insulation detection module and the display output module respectively; The main control module obtains the collected data and the detection data from the BMS communication collection module, the electrical performance collection module and the insulation detection module, and sends the collected data and the detection data to the display output module; The main control module includes a BMS battery total voltage deviation data processing submodule, a BMS battery current deviation data processing submodule, a battery cell maximum pressure difference data processing submodule, a battery cell average difference curve data processing submodule, a SOC deviation data processing submodule, a charge and discharge temperature analysis data processing submodule, an insulation performance test data processing submodule, a DC internal resistance test data processing submodule, an energy efficiency test data processing submodule and a charge and discharge energy test data processing submodule; The non-vehicle-mounted new energy vehicle power battery performance online detection system implements the above-mentioned non-vehicle-mounted new energy vehicle power battery performance online detection method.

[0007] The beneficial effects of the present invention are as follows: a non-vehicle-mounted new energy vehicle power battery performance online detection method and system of the present invention do not rely on the vehicle-mounted battery management system, and display the voltage, current, temperature and other data information of the vehicle power battery through an independent detection system that is externally connected to the vehicle, and at the same time detect the charging and discharging insulation state, SOC state parameters, DC internal resistance parameters, charging and discharging energy, etc., which can clearly and intuitively understand the real-time working state of the vehicle power battery, and solve the problem that the vehicle-mounted BMS detection technology of various vehicle manufacturers is different, the evaluation standards are not unified, and there are large deviations in the test results of the battery; at the same time, the use of automated control detection mode reduces detection errors and reduces safety risks, and the operation is simple and the measurement accuracy is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 A roadmap of an on-line detection method for the performance of a power battery of a non-vehicle-mounted new energy vehicle according to an embodiment of the present invention; Figure 2 A flowchart of the charging preparation phase of an online detection method for the performance of a power battery of a non-vehicle-mounted new energy vehicle according to an embodiment of the present invention; Figure 3 A flow chart of the charging process stages of a method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle according to an embodiment of the present invention; Figure 4 This is a flow chart of the charging end stage of a method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle according to an embodiment of the present invention; Figure 5 This is an internal schematic diagram of a main control module of a non-vehicle-mounted new energy vehicle power battery performance online detection system according to an embodiment of the present invention; Figure 6 This is an internal schematic diagram of a BMS communication acquisition module of an off-vehicle new energy vehicle power battery performance online detection system according to an embodiment of the present invention; Figure 7 A topological structure diagram of a non-vehicle-mounted new energy vehicle power battery performance online detection system according to an embodiment of the present invention; Figure 8 The internal structure and circuit diagram of a guidance circuit module of an off-vehicle new energy vehicle power battery performance online detection system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0009] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in conjunction with the implementation modes and the accompanying drawings.

[0010] Please refer to Figure 1 A method for online detection of power battery performance of non-vehicle-mounted new energy vehicles comprises the following steps: S1. Connect the charger and the new energy vehicle through the pilot circuit module; S2. Performing data collection and performance testing on the power battery of the new energy vehicle in the charging preparation stage through the insulation detection module and the BMS communication acquisition module; S3, collecting data and performing performance testing on the power battery of the new energy vehicle during the charging process through the electrical performance collection module and the BMS communication collection module; S4, collecting data from the power battery of the new energy vehicle at the end of charging through the BMS communication collection module; S5. According to the battery data obtained in steps S2 to S4, the main control module performs detection and analysis on the battery performance.

[0011] From the above description, it can be seen that the beneficial effects of the present invention are: a non-vehicle-mounted new energy vehicle power battery performance online detection method of the present invention does not rely on the vehicle-mounted battery management system, and displays the voltage, current, temperature and other data information of the vehicle power battery through an independent detection system that is externally connected to the vehicle, and simultaneously detects the charging and discharging insulation state, SOC state parameters, DC internal resistance parameters, charging and discharging energy, etc., which can clearly and intuitively understand the real-time working state of the vehicle power battery, and solves the problem that the vehicle-mounted BMS detection technologies of various vehicle manufacturers are different, the evaluation standards are not unified, and there are large deviations in the test results of the battery; at the same time, the use of automated control detection mode reduces detection errors and reduces safety risks, and the operation is simple and the measurement accuracy is high.

[0012] Furthermore, the detection and analysis of battery performance includes the analysis and calculation of the vehicle power battery total voltage deviation, the vehicle power battery total current deviation, the single cell voltage maximum deviation value, the single cell voltage maximum average difference value, the vehicle power battery SOC deviation, the vehicle power battery temperature change detection data, the insulation performance test data, the vehicle power battery pack internal resistance, the vehicle power battery pack energy efficiency and the vehicle power battery pack charge and discharge total energy analysis.

[0013] From the above description, it can be seen that conducting multi-faceted performance testing and analysis of vehicle power batteries, including indicators such as voltage, current, SOC, temperature, insulation, internal resistance, energy efficiency, and total charge and discharge energy, can effectively improve the safety of vehicle power batteries, extend service life, optimize performance, and control usage costs.

[0014] Further, the vehicle power battery total voltage deviation is obtained by analyzing the BMS battery total voltage deviation data processing submodule of the main control module, including the steps of: Obtain the actual charge and discharge voltage data and the collected BMS voltage data to obtain the instantaneous vehicle power battery total voltage deviation U acc ; ; Calculate the total voltage deviation of the vehicle power battery according to the instant total voltage deviation of the vehicle power battery corresponding to the pre-divided vehicle charging and discharging time period ; ; Among them, U1 is the actual charge and discharge voltage, in V; U2 is the collected BMS voltage, in V; U acci It is the instant total voltage deviation of the vehicle power battery at each period during the vehicle charging and discharging time; The total current deviation of the vehicle power battery is obtained by analyzing the BMS battery current deviation data processing submodule of the main control module, including the steps of: The instant vehicle power battery current deviation I is calculated based on the actual charge and discharge current data and the collected BMS current data. acc ; ; Calculate the vehicle power battery current deviation according to the instant vehicle power battery current deviation corresponding to the pre-divided vehicle charging and discharging time period ; ; Among them, I1 is the actual charge and discharge current, in amperes; I2 is the collected BMS current, in amperes; I acci It is the instantaneous vehicle power battery current deviation at each period during the vehicle charging and discharging time.

[0015] From the above description, it can be seen that the specific data processing sub-module of the main control module analyzes and calculates the total voltage deviation and total current deviation of the vehicle's power battery, which can accurately obtain the deviation of the total battery voltage and total current during the vehicle's charging and discharging process, so as to facilitate timely detection of abnormalities in the voltage and current output of the battery system, thereby effectively ensuring the stability and reliability of the battery's working state, and can provide early warning of potential faults, avoid battery overheating, overcharging and over-discharging caused by abnormal voltage and current, and improve battery safety and service life.

[0016] Furthermore, the maximum deviation value of the single cell voltage is obtained by analyzing the battery single cell maximum voltage difference data processing submodule of the main control module, including the steps of: Obtain the highest cell voltage and the lowest cell voltage of each battery cell in the vehicle power battery pack during the charging and discharging process, and calculate the maximum voltage deviation U between each battery cell △ ; ; The maximum voltage deviation of the single cell voltage is calculated based on the maximum voltage deviation corresponding to the state of charge SOC during the charging and discharging process of the vehicle power battery. ; ; Among them U H It is the highest cell voltage among all battery cells, in volts V; U L It is the lowest cell voltage among all battery cells, in volts V; U △ is the maximum voltage deviation during the instantaneous monomer charging and discharging process, is the maximum deviation value of the single cell voltage; The maximum average difference value of the single cell voltage is obtained by analyzing the battery single cell average difference curve data processing submodule of the main control module, including the steps of: Obtain the highest cell voltage, the lowest cell voltage and the average cell voltage of each battery cell in the vehicle power battery pack; Based on the maximum cell voltage and the average cell voltage, a deviation value between the maximum cell voltage and the average cell voltage in each battery cell of the instant vehicle power battery pack is calculated; ; Among them, U H It is the highest cell voltage among all the battery cells in the vehicle power battery pack, in volts V; It is the average cell voltage value of each battery cell in the vehicle power battery pack, in volts V; U H△ It is the deviation between the highest cell voltage and the average cell voltage of each cell in the vehicle power battery pack during the instant charging and discharging process; Based on the minimum cell voltage and the average cell voltage, a deviation value between the minimum cell voltage and the average cell voltage of each battery cell of the instant vehicle power battery pack is calculated; ; Among them, U L The lowest cell voltage of each battery cell in the vehicle power battery pack, in volts V; It is the average cell voltage value of each battery cell in the vehicle power battery pack, in volts V; U L△ It is the deviation between the lowest cell voltage and the average cell voltage of each cell in the vehicle power battery pack during the instant charging and discharging process; According to the U corresponding to the state of charge SOC during the charging and discharging process of the vehicle power battery L△ with U H△ , calculate the maximum average difference of monomer voltage U MD , specifically: ; in, It is the deviation between the highest cell voltage and the average cell voltage in each battery cell of the vehicle power battery pack at each period during the vehicle charging and discharging time. The deviation between the lowest cell voltage and the average cell voltage in each battery cell of the vehicle power battery pack at each period during the vehicle's charging and discharging time.

[0017] From the above description, it can be seen that the maximum deviation value of the cell voltage and the maximum average difference value of the cell voltage are accurately analyzed through the battery cell maximum voltage difference data processing submodule and the battery cell average difference curve data processing submodule in the main control module, so as to accurately locate the extreme value of the voltage difference of each cell in the battery pack during charging and discharging, so as to timely detect the discrete degree of the performance of the cell battery, so as to quickly take balancing measures when the voltage deviation is too large, to prevent the overall performance of the battery pack from being reduced or safety hazards caused by excessive charging and discharging of individual cells, effectively ensure the overall stability and safety of the battery pack, and extend the service life of the battery pack; for the analysis of the maximum average difference value of the cell voltage, understanding the deviation of each cell voltage from the average voltage is helpful to evaluate the consistency of the cells inside the battery pack, so that the battery can maintain a better working state under different states of charge, improve the energy conversion efficiency of the battery, and reduce energy loss.

[0018] Further, the SOC deviation of the vehicle power battery is obtained by analyzing the SOC deviation data processing submodule of the main control module, including the steps of: Get the actual charge and discharge voltage, current and time, and calculate the SOC value. The calculation formula is: ; Among them, SOC now is the calculated value of the current SOC; SOC past is the initial SOC; C max is the rated capacity of the battery, in Ah; I now is the current, charging is positive and discharging is negative; t is the charging time or discharging time; According to the SOC calculation value and the collected BMS state of charge SOC data, the instant vehicle power battery SOC deviation SOC is calculated acc ; ; Among them, SOC now is the SOC calculation value, SOC1 is the collected SOC data; Calculate the vehicle power battery SOC deviation based on the instant vehicle power battery SOC deviation corresponding to each time node of vehicle charging and discharging ; ; Among them, SOC acci It is the instantaneous vehicle power battery SOC deviation corresponding to each time node of vehicle charging and discharging.

[0019] From the above description, it can be seen that the accurate calculation of SOC deviation through the SOC deviation data processing submodule of the main control module can provide more accurate information on the remaining power, help to accurately judge the charge and discharge depth of the battery, prevent irreversible damage to the battery caused by excessive charge and discharge, and thus extend the battery life; at the same time, it helps to provide an important basis for battery fault diagnosis, and can promptly discover problems such as battery cell performance degradation and sensor failure that may exist in abnormal SOC data, so as to facilitate early maintenance measures and reduce maintenance costs and vehicle operation risks.

[0020] Furthermore, the vehicle power battery temperature change detection data is obtained by analyzing the charge and discharge temperature analysis data processing submodule of the main control module, including the steps of: The maximum battery temperature, minimum battery temperature, maximum temperature difference, and maximum temperature rise rate of the vehicle power battery are obtained, and the temperature change detection data of the vehicle power battery is summarized and generated.

[0021] The insulation performance test data is obtained by analyzing the insulation performance test data processing submodule of the main control module, comprising the steps of: The insulation values ​​between the positive and negative terminals are tested, and the insulation performance changes are analyzed according to preset standards to obtain the insulation performance test data.

[0022] From the above description, it can be seen that the temperature change detection data is accurately obtained and summarized through the charging and discharging temperature analysis data processing submodule of the main control module, so as to timely detect local overheating or overcooling of the battery, and prevent serious safety problems such as battery performance degradation, shortened life and even thermal runaway caused by abnormal temperature in advance, and ensure that the battery is always in a suitable operating temperature range; for the insulation performance test data, by testing the insulation values ​​​​to the positive and negative ground and analyzing according to preset standards, it can effectively monitor the insulation condition between the battery system and metal parts such as the vehicle chassis, prevent the risk of electric shock to personnel due to leakage and damage to the vehicle's electronic equipment, and greatly improve the electrical safety of the vehicle during use.

[0023] Furthermore, the internal resistance of the vehicle power battery pack is obtained by analyzing the DC internal resistance test data processing submodule of the main control module, including the steps of: The internal resistance of the current vehicle power battery pack is calculated based on the IEC DC impedance test method. The specific calculation method is: ; Among them, DCR t is the internal resistance of the vehicle's power battery pack, U1 is the voltage at the end of discharging for 10s or charging for 10s, and U2 is the voltage at the end of discharging for 1s or charging for 1s; I1 is the discharge current or charging current, which is specified as 0.2C; I2 is the discharge current or charging current, which is specified as 1C.

[0024] From the above description, it can be seen that the DC internal resistance test data processing sub-module of the main control module analyzes and calculates the internal resistance of the vehicle power battery pack according to the IEC DC impedance test method, and can accurately calculate the DC internal resistance DCR of the vehicle power battery and evaluate the battery health status, which is beneficial to optimize the charging and discharging strategy and improve the charging efficiency; at the same time, according to the analysis of the vehicle power battery DCR, it can prevent safety risks such as thermal runaway, reduce maintenance costs, and evaluate the battery recycling value.

[0025] Furthermore, the energy efficiency of the vehicle power battery pack is obtained by analyzing the energy efficiency test data processing submodule of the main control module, including the steps of: Performing constant current discharge for a first preset time according to a preset discharge current, and standing still after the discharge is completed; Then, constant current charging is performed within a second preset time according to a preset charging current, and the time is integrated by multiplying the preset discharge current and the charging current to obtain the discharge pulse output energy and the charging pulse input energy, and the energy efficiency is calculated according to the discharge pulse output energy and the charging pulse input energy, and the calculation formula is: ; in, is the energy efficiency of the vehicle power battery pack, E o is the discharge pulse output energy, E i Input energy for the charging pulse.

[0026] From the above description, it can be seen that the energy conversion of the battery pack during the charging and discharging process is quantified. The efficiency of converting the input energy of the battery pack into output energy that can be used by the vehicle in each charging and discharging cycle can be clarified based on the quantified results, thereby intuitively monitoring the energy utilization of the battery pack, which is conducive to analyzing and improving the battery cell performance, battery management system control strategy, thermal management system and other aspects, thereby improving the energy efficiency of the battery pack and extending the vehicle's cruising range.

[0027] Furthermore, the total charge and discharge energy of the vehicle power battery pack is obtained by analyzing the charge and discharge energy test data processing submodule of the main control module, including the steps of: The continuous charging power corresponding to the current SOC is found according to the current temperature, and the current charging energy is calculated according to the continuous charging power. The calculation formula is: ; Among them, E c is the current charging energy, P c The continuous charging power corresponding to the current temperature and current SOC; The continuous discharge power corresponding to the current SOC is found according to the current temperature, and the current discharge energy is calculated according to the continuous discharge power. The calculation formula is: ; Among them, E disc is the current discharge energy, P disc The continuous discharge power corresponding to the current temperature and current SOC.

[0028] From the above description, it can be seen that by calculating the energy by finding the corresponding continuous charge and discharge power through the current temperature and SOC, it is possible to accurately evaluate the energy changes of the battery under different working conditions, taking into account the influence of environmental and power factors, and realizing dynamic real-time calculation, which is conducive to optimizing battery management strategies, extending battery life, and improving energy utilization efficiency.

[0029] Please refer to Figure 7 , a non-vehicle-mounted new energy vehicle power battery performance online detection system, including a main control module, a BMS communication acquisition module, a guide circuit module, an electrical performance acquisition module, an insulation detection module and a display output module; the guide circuit module is respectively connected to the BMS communication acquisition module, the electrical performance acquisition module and the insulation detection module; The main control module is connected to the BMS communication acquisition module, the electrical performance acquisition module, the insulation detection module and the display output module respectively; The main control module obtains the collected data and the detection data from the BMS communication collection module, the electrical performance collection module and the insulation detection module, and sends the collected data and the detection data to the display output module; The main control module includes a BMS battery total voltage deviation data processing submodule, a BMS battery current deviation data processing submodule, a battery cell maximum pressure difference data processing submodule, a battery cell average difference curve data processing submodule, a SOC deviation data processing submodule, a charge and discharge temperature analysis data processing submodule, an insulation performance test data processing submodule, a DC internal resistance test data processing submodule, an energy efficiency test data processing submodule and a charge and discharge energy test data processing submodule; The non-vehicle-mounted new energy vehicle power battery performance online detection system implements the above-mentioned non-vehicle-mounted new energy vehicle power battery performance online detection method.

[0030] From the above description, it can be seen that the beneficial effects of the present invention are: a non-vehicle-mounted new energy vehicle power battery performance online detection system of the present invention does not rely on the vehicle-mounted battery management system, and displays the voltage, current, temperature and other data information of the vehicle power battery through an independent detection system that is externally connected to the vehicle, and at the same time detects the charging and discharging insulation state, SOC state parameters, DC internal resistance parameters, charging and discharging energy, etc., which can clearly and intuitively understand the real-time working state of the vehicle power battery, and solves the problem that the vehicle-mounted BMS detection technologies of various vehicle manufacturers are different, the evaluation standards are not unified, and there are large deviations in the test results of the battery; at the same time, the use of automated control detection method reduces detection errors and reduces safety risks, and the operation is simple and the measurement accuracy is high.

[0031] The present invention discloses a non-vehicle-mounted new energy vehicle power battery performance online detection method and system, which are suitable for online detection of various performances of new energy vehicle power batteries.

[0032] Please refer to Figure 1 , Embodiment 1 of the present invention is: a method for online detection of performance of a non-vehicle-mounted new energy vehicle power battery, comprising the steps of: S1. Connect the charger 2 and the new energy vehicle 3 through the guiding circuit module 1300.

[0033] In this embodiment, the steering circuit module 1300 is used to simulate the control steering circuit of the new energy vehicle 3, and to perform on-off fault simulation tests of each circuit with the charger 2 (such as a bidirectional charging and discharging pile), and to connect contacts when testing other modules.

[0034] S2. Perform data collection and performance testing on the power battery of the new energy vehicle 3 in the charging preparation stage through the insulation detection module 1500 and the BMS communication acquisition module 1200.

[0035] S3, collecting data and performing performance testing on the power battery of the new energy vehicle 3 during the charging process through the electrical performance collection module 1400 and the BMS communication collection module 1200; S4, collecting data on the power battery of the new energy vehicle 3 at the end of charging through the BMS communication collection module 1200; S5. According to the battery data obtained in steps S2 to S4, the main control module 1100 performs detection and analysis on the battery performance.

[0036] In this embodiment, the BMS communication acquisition module 1200 is used to perform interoperability and communication protocol consistency detection with the charger 2. Through the internal data acquisition sub-modules, various information data of the power battery of the new energy vehicle 3 are collected through the sub-modules according to the detection standards, and the collected and detected data are sent to the main control module 1100.

[0037] In this embodiment, Figure 6 As shown, the BMS communication acquisition module 1200 includes a BMS and vehicle identification data acquisition submodule 1201, a power battery charging parameter data acquisition submodule 1202, a battery charging demand data acquisition submodule 1203, a battery charging total status data acquisition submodule 1204, a BMS power battery status information data acquisition submodule 1205, a BMS charging suspension data acquisition submodule 1206 and a BMS statistical data acquisition submodule 1207; like Figure 5 As shown, the main control module 1100 includes a BMS battery total voltage deviation data processing submodule 1101, a BMS battery current deviation data processing submodule 1102, a battery cell maximum pressure difference data processing submodule 1103, a battery cell average difference curve data processing submodule 1104, a SOC deviation data processing submodule 1105, a charge and discharge temperature analysis data processing submodule 1106, an insulation performance test data processing submodule 1107, a DC internal resistance test data processing submodule 1108, an energy efficiency test data processing submodule 1109 and a charge and discharge energy test data processing submodule 1110.

[0038] Please refer to Figures 2 to 4 The second embodiment of the present invention is: a method for online detection of the performance of a non-vehicle-mounted new energy vehicle power battery, which is different from the first embodiment in that: The detection and analysis of battery performance in step S5 includes analysis and calculation of the total voltage deviation of the vehicle power battery, the total current deviation of the vehicle power battery, the maximum deviation value of the single cell voltage, the maximum average difference value of the single cell voltage, the SOC deviation of the vehicle power battery, the temperature change detection data of the vehicle power battery, the insulation performance test data, the internal resistance of the vehicle power battery pack, the energy efficiency of the vehicle power battery pack and the total charge and discharge energy of the vehicle power battery pack.

[0039] like Figure 2 As shown, step S2 includes: The charging preparation phase test S201 is completed by the following test process and steps: Step S202: The insulation detection module 1500 performs insulation detection and sends the detection data and results to the main control module 1100 for data processing; Step S203: the main control module 1100 distributes the acquired data to the insulation performance test data processing submodule 1107; Step S204 performs insulation performance test data processing, specifically: The insulation values ​​of the positive and negative ground of the insulation detection test are obtained, and the insulation performance changes are analyzed according to the preset standards to obtain the insulation performance test data.

[0040] Step S205 is performed in parallel with step S202 and is located after step S201. The BMS communication acquisition module 1200 performs data acquisition and testing, and sends the test data and results to the main control module 1100 for data processing.

[0041] In step S206 , the BMS and vehicle identification data collection submodule 1201 collects BMS and vehicle identification data.

[0042] In this embodiment, the BMS and vehicle identification data acquisition submodule 1201 obtains the BMS and vehicle identification data provided to the charger 2 during the vehicle handshake phase, and the BMS and vehicle identification data include battery type, rated capacity of the vehicle power battery system, rated total voltage of the vehicle power battery system, battery manufacturer name, battery pack serial number, battery pack charging times and vehicle identification code.

[0043] Step S207 is performed in parallel with step S206 and is located after step S205 , and the power battery charging parameter data collection submodule 1202 collects the power battery charging parameter data.

[0044] In this embodiment, the power battery charging parameter data acquisition submodule 1202 obtains the power battery charging parameters sent by the BMS to the charger 2 during the charging parameter configuration stage. The power battery charging parameters include the maximum allowable total charging voltage, the maximum allowable charging current, the nominal total energy of the power battery, the maximum allowable charging voltage of a single power battery, the maximum allowable temperature, the charge state of the power battery of the whole vehicle and the current battery voltage of the power battery of the whole vehicle.

[0045] Step S208 is performed in parallel with step S206 and is located after step S205 , and the battery charging demand data collection submodule 1203 collects the battery charging demand data.

[0046] In this embodiment, the battery charging requirement data collection submodule 1203 uploads the battery charging requirement to the charger 2 , and the charging requirement includes voltage requirement, current requirement and charging mode adjustment requirement.

[0047] Step S209 is performed in parallel with step S208 and is located after step S205 , and the BMS communication acquisition module 1200 performs a communication protocol consistency test with the charger 2 .

[0048] Step S210 is performed in parallel with step S206 and is located after step S205 , and the BMS communication acquisition module 1200 performs an interoperability test with the charger 2 .

[0049] In step S211 , the main control module 1100 processes the detection data and results of steps S205 to S210 .

[0050] like Figure 3 As shown, step S3 includes: The charging process stage test S301 is completed by the following test process and steps: In step S302 , the electrical performance acquisition module 1400 performs electrical performance detection, and sends the detection data and results to the main control module 1100 for data processing.

[0051] In this embodiment, the electrical performance acquisition module 1400 detects the DC technical parameters of the DC input and output circuits by means of a mutual inductor acquisition method to obtain detection data of the DC input and output circuits. In step S303 , the main control module 1100 distributes the acquired data to the sub-processing modules; in step S304 , the DC internal resistance test data processing sub-module 1108 processes the DC internal resistance test data.

[0052] Specifically, the DC internal resistance test data processing submodule 1108 of the main control module 1100 calculates the internal resistance of the current vehicle power battery pack based on the IEC DC impedance test method. The calculation method is specifically as follows: ; Among them, DCR t is the internal resistance of the vehicle's power battery pack, U1 is the voltage at the end of discharging for 10s or charging for 10s, and U2 is the voltage at the end of discharging for 1s or charging for 1s; I1 is the discharge current or charging current, which is specified as 0.2C; I2 is the discharge current or charging current, which is specified as 1C.

[0053] In step S305 , the main control module 1100 distributes the acquired data to the energy efficiency test data processing submodule 1109 for energy efficiency test data processing.

[0054] Specifically, the energy efficiency test data processing submodule 1109 of the main control module 1100 performs constant current discharge within a first preset time according to a preset discharge current, and leaves the device to stand still after the discharge is completed; Then, constant current charging is performed within a second preset time according to a preset charging current, and the time is integrated by multiplying the preset discharge current and the charging current to obtain the discharge pulse output energy and the charging pulse input energy, and the energy efficiency is calculated according to the discharge pulse output energy and the charging pulse input energy, and the calculation formula is: ; in, is the energy efficiency of the vehicle power battery pack, E o is the discharge pulse output energy, E i Input energy for the charging pulse.

[0055] In step S306 , the main control module 1100 distributes the acquired data to the charge and discharge energy test data processing submodule 1110 for charge and discharge energy test data processing.

[0056] Specifically, the actual charging power used by the vehicle power battery pack is obtained through the charging and discharging energy test data processing submodule 1110 of the main control module 1100, the continuous charging power corresponding to the current SOC is found according to the current temperature, and the current charging energy is calculated according to the continuous charging power. The calculation formula is: ; Among them, E c is the current charging energy, P c The continuous charging power corresponding to the current temperature and current SOC; The actual discharge power of the vehicle power battery pack is obtained, the continuous discharge power corresponding to the current SOC is found according to the current temperature, and the current discharge energy is calculated according to the continuous discharge power. The calculation formula is: ; Among them, E disc is the current discharge energy, P disc The continuous discharge power corresponding to the current temperature and current SOC.

[0057] Step S307 is performed in parallel with step S302 and is performed after step S301. The BMS communication acquisition module 1200 performs data acquisition and sends the detection data and results to the main control module 1100 for data processing; In step S308 , the battery charging status data collection submodule 1204 collects the battery charging status data.

[0058] In this embodiment, the battery charging total status data acquisition submodule 1204 monitors the charging process through the charger 2 and obtains the charging status data of the battery pack, wherein the charging status data includes the charging voltage measurement value, the charging current measurement value, the highest single power battery voltage and its number, the lowest single power battery voltage and its number, the current state of charge SOC and the estimated remaining charging time.

[0059] Step S309 is performed in parallel with step S308 and is performed after step S307. The BMS sends the power battery status information data collection submodule 1205 to collect the power battery status information data.

[0060] In this embodiment, the BMS sends the power battery status information data acquisition submodule 1205 to obtain the power battery status information data sent by the BMS to the charger 2 during the charging stage, and the power battery status information data includes the maximum power battery temperature, the maximum temperature detection point number, the minimum power battery temperature and the minimum power battery temperature detection point number.

[0061] In step S310 , the main control module 1100 distributes the data acquired in steps S307 to S309 to the sub-processing modules.

[0062] In step S311 , the main control module 1100 distributes the acquired data to the BMS battery total voltage deviation data processing submodule 1101 to process the vehicle power battery total voltage deviation data.

[0063] Specifically, the BMS battery total voltage deviation data processing submodule 1101 of the main control module 1100 obtains the actual charge and discharge voltage data and the collected BMS voltage data to obtain the instant vehicle power battery total voltage deviation U acc ; ; Calculate the total voltage deviation of the vehicle power battery according to the instant total voltage deviation of the vehicle power battery corresponding to the pre-divided vehicle charging and discharging time period ; ; Among them, U1 is the actual charge and discharge voltage, in V; U2 is the collected BMS voltage, in V; U acci It is the instantaneous total voltage deviation of the vehicle power battery at each period during the vehicle charging and discharging time.

[0064] Step S312 is performed in parallel with step S311 and is located after step S310. The main control module 1100 distributes the acquired data to the BMS battery current deviation data processing submodule 1102 to process the vehicle power battery total current deviation data.

[0065] Specifically, the BMS battery current deviation data processing submodule 1102 of the main control module 1100 calculates the instantaneous vehicle power battery current deviation I according to the actual charge and discharge current data and the collected BMS current data. acc ; ; Calculate the vehicle power battery current deviation according to the instant vehicle power battery current deviation corresponding to the pre-divided vehicle charging and discharging time period ; ; Among them, I1 is the actual charge and discharge current, in amperes; I2 is the collected BMS current, in amperes; I acci It is the instantaneous vehicle power battery current deviation at each period during the vehicle charging and discharging time.

[0066] Step S313 is performed in parallel with step S311 and is located after step S310. The main control module 1100 distributes the acquired data to the battery cell maximum pressure difference data processing submodule 1103 to perform battery cell maximum pressure difference data processing.

[0067] Specifically, the maximum cell voltage and the minimum cell voltage of each cell of the vehicle power battery pack during the charging and discharging process are obtained through the battery cell maximum voltage difference data processing submodule 1103 of the main control module 1100, and the maximum voltage deviation U between each battery cell is calculated. △ ; ; The maximum voltage deviation of the single cell voltage is calculated based on the maximum voltage deviation corresponding to the state of charge SOC during the charging and discharging process of the vehicle power battery. ; ; Among them U H It is the highest cell voltage among all battery cells, in volts V; U L It is the lowest cell voltage among all battery cells, in volts V; U △ is the maximum voltage deviation during the instantaneous monomer charging and discharging process, It is the maximum deviation value of single cell voltage.

[0068] Step S314 is performed in parallel with step S311 and is performed after step S310. The main control module 1100 distributes the acquired data to the battery cell average difference curve data processing submodule 1104 to process the battery cell average difference curve data.

[0069] Specifically, the maximum cell voltage, the minimum cell voltage and the average cell voltage of each battery cell in the vehicle power battery pack are obtained through the battery cell average difference curve data processing submodule 1104 of the main control module 1100; Based on the maximum cell voltage and the average cell voltage, a deviation value between the maximum cell voltage and the average cell voltage in each battery cell of the instant vehicle power battery pack is calculated; ; Among them, U H It is the highest cell voltage among all the battery cells in the vehicle power battery pack, in volts V; It is the average cell voltage value of each battery cell in the vehicle power battery pack, in volts V; U H△It is the deviation between the highest cell voltage and the average cell voltage of each cell in the vehicle power battery pack during the instant charging and discharging process; Based on the minimum cell voltage and the average cell voltage, a deviation value between the minimum cell voltage and the average cell voltage of each battery cell of the instant vehicle power battery pack is calculated; ; Among them, U L The lowest cell voltage of each battery cell in the vehicle power battery pack, in volts V; It is the average cell voltage value of each battery cell in the vehicle power battery pack, in volts V; U L△ It is the deviation between the lowest cell voltage and the average cell voltage of each cell in the vehicle power battery pack during the instant charging and discharging process; According to the U corresponding to the state of charge SOC during the charging and discharging process of the vehicle power battery L△ with U H△ , calculate the maximum average difference of monomer voltage U MD , specifically: ; in, It is the deviation between the highest cell voltage and the average cell voltage in each battery cell of the vehicle power battery pack at each period during the vehicle charging and discharging time. The deviation between the lowest cell voltage and the average cell voltage in each battery cell of the vehicle power battery pack at each period during the vehicle's charging and discharging time.

[0070] Step S315 is performed in parallel with step S311 and is located after step S310. The main control module 1100 distributes the acquired data to the SOC deviation data processing submodule 1105 for SOC deviation data processing.

[0071] Specifically, the actual charge and discharge voltage, current and time are obtained, and the SOC calculation value is calculated by the SOC deviation data processing submodule 1105 of the main control module 1100; ; Among them, SOC now is the calculated value of the current SOC; SOC past is the initial SOC; C max is the rated capacity of the battery, in Ah; I now is the current, charging is positive and discharging is negative; t is the charging time or discharging time; According to the SOC calculation value and the collected BMS state of charge SOC data, the instant vehicle power battery SOC deviation SOC is calculated acc ; ; Among them, SOC now is the SOC calculation value, SOC1 is the collected SOC data; Calculate the vehicle power battery SOC deviation based on the instant vehicle power battery SOC deviation corresponding to each time node of vehicle charging and discharging ; ; Among them, SOC acci It is the instantaneous vehicle power battery SOC deviation corresponding to each time node of vehicle charging and discharging.

[0072] Step S316 is performed in parallel with step S311 and is located after step S310. The main control module 1100 distributes the acquired data to the charge and discharge temperature analysis data processing submodule 1106 for charge and discharge temperature analysis data processing.

[0073] Specifically, the maximum battery temperature, minimum battery temperature, maximum temperature difference, and maximum temperature rise rate of the vehicle power battery are obtained through the charge and discharge temperature analysis data processing submodule 1106 of the main control module 1100, and the temperature change detection data of the vehicle power battery is summarized and generated.

[0074] In this embodiment, high-precision temperature sensors are installed at different locations of the vehicle's power battery to transmit temperature data to the vehicle's electronic control system or a dedicated data acquisition unit in real time, and the appropriate data recording frequency is determined according to demand to record the temperature values ​​of each sensor.

[0075] In this embodiment, the temperature values ​​collected by the various sensors are compared in real time, and the maximum value thereof is determined as the maximum battery temperature; and the minimum value thereof is determined as the minimum battery temperature.

[0076] In this embodiment, the maximum temperature difference is the difference between the highest battery temperature and the lowest battery temperature. After obtaining the highest and lowest temperatures, the difference between the two is calculated and recorded in real time. Whenever the highest or lowest temperature is updated, the maximum temperature difference is recalculated.

[0077] In this embodiment, the temperature change values ​​at adjacent time points (such as the current collection time and the previous collection time) are recorded, and the temperature change value is divided by the time interval to obtain the temperature rise rate. During the operation of the vehicle, the temperature rise rates of each time period are continuously calculated and compared, and the maximum value is recorded as the maximum temperature rise rate.

[0078] like Figure 4 As shown, step S4 includes: The charging end stage test S401 is completed by the following test process and steps: In step S402 , the BMS communication acquisition module 1200 performs data acquisition and sends the detection data and results to the main control module 1100 for data processing.

[0079] In step S403 , the BMS charging suspension data collection submodule 1206 performs BMS charging suspension data collection.

[0080] In this embodiment, the BMS charging suspension data acquisition submodule 1206 obtains the charging suspension data fed back after the charging fault and sends it to the charger 2. The charging suspension data includes the BMS charging suspension reason, the BMS charging suspension fault reason and the BMS charging suspension error reason.

[0081] Step S404 is performed in parallel with step S303 and is performed after step S402. The BMS statistical data collection submodule 1207 collects BMS statistical data.

[0082] In this embodiment, the BMS statistical data collection submodule 1207 obtains the charging statistical data of this charging process and sends it to the charger 2. The charging statistical data includes the termination state of charge SOC, the minimum voltage of the power battery cell, the maximum voltage of the power battery cell, the maximum temperature of the power battery and the minimum temperature of the power battery.

[0083] In step S405 , the main control module 1100 processes the data in steps S402 to S404 .

[0084] Please refer to Figures 5 to 8 , Embodiment 3 of the present invention is: A non-vehicle-mounted new energy vehicle power battery performance online detection system 1 includes a main control module 1100, a BMS communication acquisition module 1200, a guidance circuit module 1300, an electrical performance acquisition module 1400, an insulation detection module 1500 and a display output module 1600; the guidance circuit module 1300 is respectively connected to the BMS communication acquisition module 1200, the electrical performance acquisition module 1400 and the insulation detection module 1500; The main control module 1100 is respectively connected to the BMS communication acquisition module 1200, the electrical performance acquisition module 1400, the insulation detection module 1500 and the display output module 1600; The main control module 1100 obtains the collected data and the detected data from the BMS communication collection module 1200, the electrical performance collection module 1400 and the insulation detection module 1500, and sends the collected data and the detected data to the display output module 1600; The main control module 1100 includes a BMS battery total voltage deviation data processing submodule 1101, a BMS battery current deviation data processing submodule 1102, a battery cell maximum pressure difference data processing submodule 1103, a battery cell average difference curve data processing submodule 1104, a SOC deviation data processing submodule 1105, a charge and discharge temperature analysis data processing submodule 1106, an insulation performance test data processing submodule 1107, a DC internal resistance test data processing submodule 1108, an energy efficiency test data processing submodule 1109 and a charge and discharge energy test data processing submodule 1110; The non-vehicle-mounted new energy vehicle power battery performance online detection system 1 implements the non-vehicle-mounted new energy vehicle power battery performance online detection method described in the above embodiment one or two.

[0085] Among them, the BMS communication acquisition module 1200 includes a BMS and vehicle identification data acquisition submodule 1201, a power battery charging parameter data acquisition submodule 1202, a battery charging demand data acquisition submodule 1203, a battery charging total status data acquisition submodule 1204, a BMS sending power battery status information data acquisition submodule 1205, a BMS charging suspension data acquisition submodule 1206 and a BMS statistical data acquisition submodule 1207.

[0086] In this embodiment, Figure 8 As shown, the steering circuit module 1300 includes nine pairs of contacts and wires, namely DC+, DC-, PE, S+, S-, CC1, CC2, A+, A-, selective switches K1, K2, C1, C2, K3, K4, an equivalent resistor R3 and its subordinate selective switch K.

[0087] Among them, the DC power positive (DC+) contact pair and wire are used to connect the direct power positive and the vehicle battery positive pole for power transmission; used to connect the voltage transformer (PT) and current transformer (CT) of the electrical performance acquisition module 1400 to perform voltage and current tests on the transmitted power; used to connect to the insulation detection module 1500 to test the access resistance value through an adjustable resistance loop for insulation performance testing.

[0088] The DC power negative (DC-) contact pair and wire are used to connect the direct power negative and the vehicle battery negative pole for power transmission; used to connect the voltage transformer (PT) of the electrical performance acquisition module 1400 to perform voltage testing of the transmitted power; used to connect to the insulation detection module 1500 to test the access resistance value through an adjustable resistance loop to perform insulation performance testing.

[0089] The protective grounding (PE) contact pair and wire are used to connect the ground wire of the power supply equipment and the vehicle power platform; used to connect with the insulation detection module 1500, test the access resistance value through the adjustable resistance loop, and perform insulation performance detection. It is used to connect the equivalent resistor R3 and its subordinate selective switch K to perform the adjustable resistance test and on-off fault simulation test of the equivalent resistor R3.

[0090] The charging communication CAN_H (S+) contact pair and wire are used to connect the communication line of the off-board charger 2 and the electric vehicle; and are used to connect the BMS communication acquisition module 1200 to perform interoperability and communication protocol consistency detection through CAN communication.

[0091] The charging communication CAN_L (S-) contact pair and wire are used to connect the communication line of the off-board charger 2 and the electric vehicle; and are used to connect the BMS communication acquisition module 1200 to perform interoperability and communication protocol consistency detection through CAN communication.

[0092] The first charging connection confirmation (CC1) contact pair and wire are used to monitor and confirm the physical connection status of the off-board charger 2.

[0093] The second charging connection confirmation (CC2) contact pair and wire are used to monitor and confirm the physical connection status of the electric vehicle; they are used to connect the equivalent resistor R3 and its subordinate selective switch K to perform an adjustable resistance test and an on-off fault simulation test of the equivalent resistor R3.

[0094] The low-voltage auxiliary power positive (A+) contact pair and wire are used to connect the low-voltage auxiliary power provided by the off-board charger 2 to the electric vehicle.

[0095] The low-voltage auxiliary power supply negative (A-) contact pair and wire are used to connect the low-voltage auxiliary power supply provided by the off-board charger 2 for the electric vehicle.

[0096] The selective switch K1 is used for the on-off fault simulation test of the DC+ circuit; the selective switch K2 is used for the on-off fault simulation test of the DC- circuit; the selective switch C1 is used for the on-off fault simulation test of the S+ circuit; the selective switch C2 is used for the on-off fault simulation test of the S- circuit; the selective switch K3 is used for the on-off fault simulation test of the A+ circuit; the selective switch K4 is used for the on-off fault simulation test of the A- circuit; the equivalent resistor R3 and its subordinate selective switch K are used for the adjustable resistance test and on-off fault simulation test of the CC2 circuit.

[0097] In summary, the present invention provides a non-vehicle-mounted new energy vehicle power battery performance online detection method and system, which does not rely on the vehicle-mounted battery management system, and displays the voltage, current, temperature and other data information of the vehicle power battery through an independent detection system connected to the non-vehicle external device, and simultaneously detects the charging and discharging insulation state, SOC state parameters, DC internal resistance parameters, charging and discharging energy, etc., so as to clearly and intuitively understand the real-time working state of the vehicle power battery, and solves the problem that the vehicle-mounted BMS detection technologies of various vehicle manufacturers are different, the evaluation standards are not unified, and there are large deviations in the test results of the battery; at the same time, the automatic control detection method is adopted to reduce the detection error and reduce the safety risk, and the operation is simple and the measurement accuracy is high.

[0098] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for online detection of power battery performance of non-vehicle-mounted new energy vehicles, characterized in that: Includes steps: S1. Connect the charger and the new energy vehicle through the pilot circuit module; S2. Performing data collection and performance testing on the power battery of the new energy vehicle in the charging preparation stage through the insulation detection module and the BMS communication acquisition module; S3, collecting data and performing performance testing on the power battery of the new energy vehicle during the charging process through the electrical performance collection module and the BMS communication collection module; S4, collecting data from the power battery of the new energy vehicle at the end of charging through the BMS communication collection module; S5. According to the battery data obtained in steps S2 to S4, the main control module performs detection and analysis on the battery performance.

2. The method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle according to claim 1, characterized in that: The detection and analysis of battery performance includes the analysis and calculation of the vehicle power battery total voltage deviation, vehicle power battery total current deviation, single cell voltage maximum deviation value, single cell voltage maximum average difference value, vehicle power battery SOC deviation, vehicle power battery temperature change detection data, insulation performance test data, vehicle power battery pack internal resistance, vehicle power battery pack energy efficiency and vehicle power battery pack charge and discharge total energy.

3. The method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle according to claim 2 is characterized in that: The vehicle power battery total voltage deviation is obtained by analyzing the BMS battery total voltage deviation data processing submodule of the main control module, including the steps of: Obtain the actual charge and discharge voltage data and the collected BMS voltage data to obtain the instantaneous vehicle power battery total voltage deviation U acc ; ; Calculate the total voltage deviation of the vehicle power battery according to the instant total voltage deviation of the vehicle power battery corresponding to the pre-divided vehicle charging and discharging time period ; ; Among them, U1 is the actual charge and discharge voltage, in V; U2 is the collected BMS voltage, in V; U acci It is the instant total voltage deviation of the vehicle power battery at each period during the vehicle charging and discharging time; The total current deviation of the vehicle power battery is obtained by analyzing the BMS battery current deviation data processing submodule of the main control module, including the steps of: The instant vehicle power battery current deviation I is calculated based on the actual charge and discharge current data and the collected BMS current data. acc ; ; Calculate the vehicle power battery current deviation according to the instant vehicle power battery current deviation corresponding to the pre-divided vehicle charging and discharging time period ; ; Among them, I1 is the actual charge and discharge current, in amperes; I2 is the collected BMS current, in amperes; I acci It is the instantaneous vehicle power battery current deviation at each period during the vehicle charging and discharging time.

4. The method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle according to claim 2 is characterized in that: The maximum deviation value of the single cell voltage is obtained by analyzing the battery single cell maximum voltage difference data processing submodule of the main control module, including the steps of: Obtain the highest cell voltage and the lowest cell voltage of each battery cell in the vehicle power battery pack during the charging and discharging process, and calculate the maximum voltage deviation U between each battery cell △ ; ; The maximum voltage deviation of the single cell voltage is calculated based on the maximum voltage deviation corresponding to the state of charge SOC during the charging and discharging process of the vehicle power battery. ; ; Among them U H It is the highest cell voltage among all battery cells, in volts V; U L It is the lowest cell voltage among all battery cells, in volts V; U △ is the maximum voltage deviation during the instantaneous monomer charging and discharging process, is the maximum deviation value of the single cell voltage; The maximum average difference value of the single cell voltage is obtained by analyzing the battery single cell average difference curve data processing submodule of the main control module, including the steps of: Obtain the highest cell voltage, the lowest cell voltage and the average cell voltage of each battery cell in the vehicle power battery pack; Based on the maximum cell voltage and the average cell voltage, a deviation value between the maximum cell voltage and the average cell voltage in each battery cell of the instant vehicle power battery pack is calculated; ; Among them, U H It is the highest cell voltage among all the battery cells in the vehicle power battery pack, in volts V; It is the average cell voltage value of each battery cell in the vehicle power battery pack, in volts V; U H△ It is the deviation between the highest cell voltage and the average cell voltage of each cell in the vehicle power battery pack during the instant charging and discharging process; Based on the minimum cell voltage and the average cell voltage, a deviation value between the minimum cell voltage and the average cell voltage of each battery cell in the instant vehicle power battery pack is calculated; ; Among them, U L The lowest cell voltage of each battery cell in the vehicle power battery pack, in volts V; It is the average cell voltage value of each battery cell in the vehicle power battery pack, in volts V; U L△ It is the deviation between the lowest cell voltage and the average cell voltage of each cell in the vehicle power battery pack during the instant charging and discharging process; According to the U corresponding to the state of charge SOC during the charging and discharging process of the vehicle power battery L△ with U H△ , calculate the maximum average difference of monomer voltage U MD , specifically: ; in, It is the deviation between the highest cell voltage and the average cell voltage of each battery cell in the vehicle power battery pack at each period during the vehicle charging and discharging time. The deviation between the lowest cell voltage and the average cell voltage in each battery cell of the vehicle power battery pack at each period during the vehicle's charging and discharging time.

5. The method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle according to claim 2, characterized in that: The vehicle power battery SOC deviation is obtained by analyzing the SOC deviation data processing submodule of the main control module, including the steps of: Get the actual charge and discharge voltage, current and time, and calculate the SOC value. The calculation formula is: ; Among them, SOC now is the calculated value of the current SOC; SOC past is the initial SOC; C max is the rated capacity of the battery, in Ah; I now is the current, charging is positive and discharging is negative; t is the charging time or discharging time; According to the SOC calculation value and the collected BMS state of charge SOC data, the instant vehicle power battery SOC deviation SOC is calculated acc ; ; Among them, SOC now is the SOC calculation value, SOC1 is the collected SOC data; Calculate the vehicle power battery SOC deviation based on the instant vehicle power battery SOC deviation corresponding to each time node of vehicle charging and discharging ; ; Among them, SOC acci It is the instantaneous vehicle power battery SOC deviation corresponding to each time node of vehicle charging and discharging.

6. The method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle according to claim 2 is characterized in that: The vehicle power battery temperature change detection data is obtained by analyzing the charge and discharge temperature analysis data processing submodule of the main control module, including the steps of: Obtain the maximum battery temperature, minimum battery temperature, maximum temperature difference, and maximum temperature rise rate of the vehicle power battery, and summarize and generate temperature change detection data of the vehicle power battery; The insulation performance test data is obtained by analyzing the insulation performance test data processing submodule of the main control module, and comprises the steps of: The insulation values ​​between the positive and negative terminals are tested, and the insulation performance changes are analyzed according to preset standards to obtain the insulation performance test data.

7. The method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle according to claim 2 is characterized in that: The internal resistance of the vehicle power battery pack is obtained by analyzing the DC internal resistance test data processing submodule of the main control module, including the steps of: The internal resistance of the current vehicle power battery pack is calculated based on the IEC DC impedance test method. The specific calculation method is: ; Among them, DCR t is the internal resistance of the vehicle's power battery pack, U1 is the voltage at the end of discharging for 10s or charging for 10s, and U2 is the voltage at the end of discharging for 1s or charging for 1s; I1 is the discharge current or charging current, which is specified as 0.2C; I2 is the discharge current or charging current, which is specified as 1C.

8. The method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle according to claim 2 is characterized in that: The energy efficiency of the vehicle power battery pack is obtained by analyzing the energy efficiency test data processing submodule of the main control module, including the steps of: Performing constant current discharge for a first preset time according to a preset discharge current, and standing still after the discharge is completed; Then, constant current charging is performed within a second preset time according to a preset charging current, and the time is integrated by multiplying the preset discharge current and the charging current to obtain the discharge pulse output energy and the charging pulse input energy, and the energy efficiency is calculated according to the discharge pulse output energy and the charging pulse input energy, and the calculation formula is: ; in, is the energy efficiency of the vehicle power battery pack, E o is the discharge pulse output energy, E i Input energy for the charging pulse.

9. The method for online detection of power battery performance of a non-vehicle-mounted new energy vehicle according to claim 2, characterized in that: The total charge and discharge energy of the vehicle power battery pack is obtained by analyzing the charge and discharge energy test data processing submodule of the main control module, including the steps of: The continuous charging power corresponding to the current SOC is found according to the current temperature, and the current charging energy is calculated according to the continuous charging power. The calculation formula is: ; Among them, E c is the current charging energy, P c The continuous charging power corresponding to the current temperature and current SOC; The continuous discharge power corresponding to the current SOC is found according to the current temperature, and the current discharge energy is calculated according to the continuous discharge power. The calculation formula is: ; Among them, E disc is the current discharge energy, P disc The continuous discharge power corresponding to the current temperature and current SOC.

10. A non-vehicle-mounted new energy vehicle power battery performance online detection system, characterized in that: It includes a main control module, a BMS communication acquisition module, a guide circuit module, an electrical performance acquisition module, an insulation detection module and a display output module; the guide circuit module is respectively connected to the BMS communication acquisition module, the electrical performance acquisition module and the insulation detection module; The main control module is respectively connected to the BMS communication acquisition module, the electrical performance acquisition module, the insulation detection module and the display output module; The main control module obtains the collected data and the detection data from the BMS communication collection module, the electrical performance collection module and the insulation detection module, and sends the collected data and the detection data to the display output module; The main control module includes a BMS battery total voltage deviation data processing submodule, a BMS battery current deviation data processing submodule, a battery cell maximum pressure difference data processing submodule, a battery cell average difference curve data processing submodule, a SOC deviation data processing submodule, a charge and discharge temperature analysis data processing submodule, an insulation performance test data processing submodule, a DC internal resistance test data processing submodule, an energy efficiency test data processing submodule and a charge and discharge energy test data processing submodule; The non-vehicle-mounted new energy vehicle power battery performance online detection system implements the non-vehicle-mounted new energy vehicle power battery performance online detection method described in any one of claims 1-9.

Images