Vehicle lithium battery lithium precipitation identification method and device

Abstract

The invention provides a lithium precipitation recognition method and device for a vehicle lithium battery, and belongs to the technical field of lithium precipitation recognition. When a battery management system recognizes that the vehicle lithium battery meets the lithium precipitation recognition working condition, a lithium precipitation detection mode is started, and a constant low-rate discharge request is generated and sent to a whole vehicle energy distribution system; and the whole vehicle energy distribution system maintains the vehicle lithium battery to discharge in a temperature range through energy distribution, calculates lithium precipitation characteristic parameters of the vehicle lithium battery in real time and uploads the lithium precipitation characteristic parameters to the cloud platform, and the cloud platform calculates the lithium precipitation capacity of the vehicle lithium battery in combination with historical data. Therefore, the advantages of a power source of the hybrid electric vehicle are fully utilized, constant small-rate discharging of the vehicle lithium battery at the proper temperature is achieved, and lithium precipitation characteristic parameters are obtained through a battery management system under the condition that a sensor is not additionally arranged; and a vehicle cloud cooperation mode is adopted, lithium precipitation characteristic parameters are analyzed in real time, the lithium precipitation condition is confirmed and dealt with, and therefore stable and safe operation of the vehicle is guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of lithium deposition identification, and in particular to a method and device for identifying lithium deposition in a lithium battery for a vehicle. Background Art

[0002] When electric vehicle lithium-ion batteries are charged at low temperatures or quickly charged, lithium precipitation side reactions are likely to occur at the interface between the negative electrode and the electrolyte, resulting in the precipitation of lithium dendrites. The uncontrolled growth of lithium dendrites is accompanied by huge volume changes and the formation of dead lithium, causing the battery capacity to decay rapidly, resulting in a reduction in the vehicle's cruising range. The growing lithium dendrites may puncture the diaphragm, causing a short circuit in the battery and increasing the risk of thermal runaway.

[0003] Among them, the lithium deposition identification methods can be divided into invasive diagnostic methods and non-invasive lithium deposition diagnostic methods according to whether the battery needs to be disassembled. Invasive methods mainly include optical imaging methods, electronic imaging methods, mass spectrometry titration methods, and titration-gas chromatography methods, but since invasive lithium deposition identification methods require disassembly of the battery, they are not suitable for battery applications. Common non-invasive methods include the excitation model method, the coulomb efficiency method, the voltage curve method, the reference electrode method, the electrochemical impedance method and the neutron diffraction method. Among them, the neutron diffraction method relies on large and expensive equipment and is difficult to integrate into the BMS. The model-driven method requires the BMS to have sufficient computing power to support the update of the mechanism model parameters and the real-time calculation of the state observer. The coulomb efficiency method requires the BMS to have high current sampling accuracy and specific working conditions of full charge and discharge to ensure the accurate calculation of the coulomb efficiency. The reference electrode method requires the implantation of a reference electrode into the lithium battery, which is not suitable for current commercial batteries. The electrochemical impedance method mainly uses the intermittent charging method and the DEIS method for the impedance information of lithium batteries. The intermittent time of the intermittent charging method will affect the charging speed of the battery, and there is currently no universal empirical formula for setting the length of the intermittent time. The DEIS method requires the use of an AC signal emitted by an AC tester to measure the impedance information during the battery charging process, which is currently difficult to directly apply to the BMS. The lithium plating characteristics required by the voltage curve method can be directly extracted from the parameters detected by the BMS, so it has the highest feasibility.

[0004] However, the current battery management system does not have the function of identifying lithium plating. Summary of the invention

[0005] In view of this, the purpose of the present application is to provide a method and device for identifying lithium plating in lithium batteries for vehicles, which can accurately detect and respond to lithium plating in lithium batteries for hybrid vehicles, and ensure stable and safe operation of the vehicle.

[0006] In the first aspect, the present application provides a method for identifying lithium plating in a lithium battery for a vehicle, which is applied to a hybrid vehicle, wherein the hybrid vehicle includes a vehicle energy distribution system, a battery management system and a cloud platform, wherein the battery management system includes a lithium plating detection mode setting module, a power system power control module, a lithium plating characteristic parameter calculation module, a lithium plating parameter cloud platform interaction module and a lithium plating response module; the identification method includes the following steps:

[0007] The lithium deposition identification working condition of the vehicle lithium battery is set based on the lithium deposition detection mode setting module, and when the battery management system identifies that the vehicle lithium battery meets the lithium deposition identification working condition, the lithium deposition detection mode is turned on; wherein the lithium deposition identification working condition includes the temperature range of the vehicle lithium battery after it is fully charged;

[0008] Generate a constant low-rate discharge request based on the power system power control module, and send it to the whole vehicle energy distribution system, and the whole vehicle energy distribution system maintains the vehicle lithium battery to discharge within the temperature range through energy distribution according to the constant low-rate discharge request;

[0009] Based on the lithium deposition characteristic parameter calculation module, the lithium deposition characteristic parameters of the automotive lithium battery during constant low-rate discharge are calculated in real time, and uploaded to the cloud platform through the lithium deposition parameter cloud platform interaction module. The cloud platform calculates the lithium deposition capacity of the automotive lithium battery based on the received lithium deposition characteristic parameters and in combination with historical data, and sends it to the battery management system.

[0010] In a possible implementation, when the battery management system recognizes that the vehicle lithium battery meets the lithium plating identification condition, starting the lithium plating detection mode includes the following steps:

[0011] When the battery management system identifies that the vehicle lithium battery meets the lithium plating identification working condition, a lithium plating detection mode start prompt is generated;

[0012] Within the set time, if the lithium deposition detection mode start acceptance instruction is received, the lithium deposition detection mode is started; if the lithium deposition detection mode start acceptance instruction is not received, the lithium deposition detection mode is abandoned.

[0013] In a possible implementation, the whole vehicle energy distribution system maintains the discharge of the vehicle lithium battery within the temperature range through energy distribution according to the constant low-rate discharge request, including the following steps:

[0014] Based on the battery management system, real-time monitoring of the working status of the vehicle energy distribution system;

[0015] If the working state of the vehicle energy distribution system is abnormal, the lithium plating detection mode is stopped.

[0016] In a possible implementation, the lithium deposition characteristic parameter is the minimum value of the battery voltage change per unit discharge capacity within a time period; the cloud platform calculates the lithium deposition capacity of the automotive lithium battery based on the received lithium deposition characteristic parameter and in combination with historical data, comprising the following steps:

[0017] Constructing a current differential voltage curve according to the received lithium deposition characteristic parameters;

[0018] Determining whether lithium deposition occurs in the vehicle lithium battery according to the change trend of the current differential voltage curve;

[0019] If it is determined that lithium deposition occurs in the vehicle lithium battery, a first discharge capacity corresponding to a first trough position of the current differential voltage curve is obtained, and a second discharge capacity corresponding to a first trough position of the historical differential voltage curve is obtained through historical data;

[0020] The difference between the first discharge capacity and the second discharge capacity is calculated to obtain the lithium deposition capacity in the time period.

[0021] In a possible implementation, judging whether lithium deposition occurs in the vehicle lithium battery according to the change trend of the current differential voltage curve includes the following steps:

[0022] If the current differential voltage curve increases monotonically, it is determined that lithium deposition does not occur in the vehicle lithium battery;

[0023] If the current differential voltage curve first increases, then decreases, and then increases again, it is determined that lithium deposition occurs in the automotive lithium battery.

[0024] In a possible implementation, the method further includes the following steps:

[0025] If it is determined that lithium plating occurs in the automotive lithium battery, the maximum lithium plating capacity is determined from the lithium plating capacities of all automotive lithium batteries;

[0026] The charging current is adjusted based on the maximum lithium plating capacity, the rated capacity and the charging rate of the vehicle lithium battery.

[0027] In a possible implementation, the temperature range of the fully charged vehicle lithium battery is set to 10° C. to 35° C.

[0028] In the second aspect, the present application provides a lithium plating identification device for a vehicle lithium battery, which is applied to a hybrid vehicle, wherein the hybrid vehicle includes a vehicle energy distribution system, a battery management system and a cloud platform, wherein the battery management system includes a lithium plating detection mode setting module, a power system power control module, a lithium plating characteristic parameter calculation module, a lithium plating parameter cloud platform interaction module and a lithium plating response module; the identification device includes:

[0029] A setting module, used to set the lithium deposition identification working condition of the vehicle lithium battery based on the lithium deposition detection mode setting module, and start the lithium deposition detection mode when the battery management system recognizes that the vehicle lithium battery meets the lithium deposition identification working condition; wherein the lithium deposition identification working condition includes the temperature range of the vehicle lithium battery after it is fully charged;

[0030] A control module, configured to generate a constant low-rate discharge request based on the power system power control module, and send the request to the vehicle energy distribution system, so that the vehicle energy distribution system maintains the discharge of the vehicle lithium battery within the temperature range through energy distribution according to the constant low-rate discharge request;

[0031] A calculation module is used to calculate the lithium deposition characteristic parameters of the vehicle lithium battery during constant low-rate discharge in real time based on the lithium deposition characteristic parameter calculation module, and upload them to the cloud platform through the lithium deposition parameter cloud platform interaction module. The cloud platform calculates the lithium deposition capacity of the vehicle lithium battery based on the received lithium deposition characteristic parameters and in combination with historical data, and sends them to the battery management system.

[0032] In a third aspect, the present application provides an electronic device, comprising: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and when the machine-readable instructions are executed by the processor, the steps of the method for identifying lithium plating in automotive lithium batteries as described in the first aspect are performed.

[0033] In a fourth aspect, the present application provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method for identifying lithium plating in a lithium battery for a vehicle as described in the first aspect are executed.

[0034] The present embodiment provides a method and device for identifying lithium plating of a lithium battery for a vehicle. The method and device set the lithium plating identification working condition of the lithium plating of the lithium battery for a vehicle based on the lithium plating detection mode setting module, and start the lithium plating detection mode when the battery management system identifies that the lithium battery for a vehicle meets the lithium plating identification working condition; generate a constant small rate discharge request based on the power system power control module, and send it to the whole vehicle energy distribution system, and the whole vehicle energy distribution system maintains the discharge of the lithium battery for a vehicle within the temperature range through energy distribution according to the constant small rate discharge request; calculate the lithium plating characteristic parameters of the lithium battery for a vehicle during constant small rate discharge in real time based on the lithium plating characteristic parameter calculation module, and upload them to the cloud platform through the lithium plating parameter cloud platform interaction module, and the cloud platform calculates the lithium plating capacity of the lithium battery for a vehicle based on the received lithium plating characteristic parameters and in combination with historical data, and sends it to the battery management system. On the one hand, the power source advantages of hybrid vehicles are fully utilized, and the energy distribution of the vehicle energy distribution system is used to achieve a constant low-rate discharge of automotive lithium batteries at an appropriate temperature. The characteristic parameters of lithium plating are obtained through the battery management system without adding additional sensors, thereby reducing costs. On the other hand, the vehicle-cloud collaboration method is adopted to analyze the characteristic parameters of lithium plating in real time, confirm the lithium plating situation and respond, thereby ensuring the stable and safe operation of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 This is a schematic diagram of the process of identifying lithium deposition in a lithium battery for a vehicle described in one embodiment of the present application;

[0037] Figure 2 A schematic diagram of the connection between the vehicle energy distribution system, the battery management system and the cloud platform in one embodiment of the present application;

[0038] Figure 3 is a schematic diagram of a current differential voltage curve described in an embodiment of the present application;

[0039] Figure 4 This is a structural block diagram of a lithium deposition identification device for a vehicle lithium battery according to an embodiment of the present application;

[0040] Figure 5 It is a structural block diagram of an electronic device described in an embodiment of the present application. DETAILED DESCRIPTION

[0041] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art can add one or more other operations to the flowchart under the guidance of the content of the present application, or remove one or more operations from the flowchart.

[0042] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application usually described and marked in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0043] It should be noted that the term "comprising" will be used in the embodiments of the present application to indicate the existence of the features declared thereafter, but does not exclude the addition of other features.

[0044] Based on the technical problems raised by the background technology, the present application provides a method and device for identifying lithium plating in lithium batteries for vehicles, which can accurately detect and deal with lithium plating in lithium batteries for hybrid vehicles, and ensure stable and safe operation of the vehicle.

[0045] See the instruction manual Figure 1 And the instruction manual Figure 2 In one embodiment, the present application provides a method for identifying lithium plating in a lithium battery for a vehicle, which is applied to a hybrid vehicle. The hybrid vehicle includes a vehicle energy distribution system, a battery management system and a cloud platform. The battery management system includes a lithium plating detection mode setting module, a power system power control module, a lithium plating characteristic parameter calculation module, a lithium plating parameter cloud platform interaction module and a lithium plating response module. The identification method includes the following steps:

[0046] S1. Setting the lithium deposition identification working condition of the vehicle lithium battery based on the lithium deposition detection mode setting module, and starting the lithium deposition detection mode when the battery management system identifies that the vehicle lithium battery meets the lithium deposition identification working condition; wherein the lithium deposition identification working condition includes the temperature range of the vehicle lithium battery after it is fully charged;

[0047] S2, generating a constant low-rate discharge request based on the power system power control module, and sending it to the whole vehicle energy distribution system, and the whole vehicle energy distribution system maintains the vehicle lithium battery to discharge within the temperature range through energy distribution according to the constant low-rate discharge request;

[0048] S3. Based on the lithium deposition characteristic parameter calculation module, the lithium deposition characteristic parameters of the vehicle lithium battery during constant low-rate discharge are calculated in real time, and uploaded to the cloud platform through the lithium deposition parameter cloud platform interaction module. The cloud platform calculates the lithium deposition capacity of the vehicle lithium battery based on the received lithium deposition characteristic parameters and in combination with historical data, and sends it to the battery management system.

[0049] Specifically, in step S1, if the battery management system recognizes that the hybrid vehicle's lithium battery has just been fully charged and the temperature of the lithium battery is appropriate, a prompt to start the lithium deposition detection mode is generated, prompting the driver to start the lithium deposition detection mode; if the lithium deposition detection mode start acceptance instruction is received within the set time, the lithium deposition detection mode is started; if the lithium deposition detection mode start acceptance instruction is not received within the set time, the lithium deposition detection mode is abandoned.

[0050] For example, the set vehicle lithium battery temperature is 10°C ~ 35°C, and the set prompt time is 2 minutes. In one embodiment, if the vehicle lithium battery of the hybrid vehicle has just been fully charged and the vehicle lithium battery temperature is 25°C, the battery management system confirms that the vehicle lithium battery meets the lithium deposition identification working condition and sends a prompt to the driver to start the lithium deposition detection mode. If the driver agrees to start the lithium deposition detection mode within 2 minutes, step S2 is executed. If the driver does not agree to start the lithium deposition detection mode within 2 minutes, it is deemed to refuse to start the lithium deposition identification mode. In another embodiment, if the vehicle lithium battery of the hybrid vehicle has just been fully charged and the vehicle lithium battery temperature is 0°C, the battery management system confirms that the vehicle lithium battery does not meet the lithium deposition identification working condition and does not send a prompt to the driver to start the lithium deposition detection mode.

[0051] In step S2, after the lithium plating detection mode is turned on, the power system power control module of the battery management system sets a constant low-rate discharge request according to the current temperature of the vehicle lithium battery and sends it to the vehicle energy distribution system. The vehicle energy distribution system ensures that the vehicle lithium battery continues to discharge at a constant low rate by adjusting the energy distribution of the high and low voltage devices of the vehicle. For example, the power supply of the hybrid vehicle during driving and idling under the lithium plating identification condition and the energy supply of the high and low voltage electronic devices of the vehicle are provided by the vehicle lithium battery in addition to the low-rate discharge, the rest is provided by the vehicle energy distribution system coordinating the engine, small battery, etc. In addition, in the lithium plating detection mode, the thermal management system adjusts the temperature to ensure that the vehicle lithium battery is discharged at a small rate at an appropriate temperature.

[0052] It should be noted that when the vehicle energy distribution system maintains the discharge of the vehicle lithium battery within the temperature range through energy distribution based on a constant small rate discharge request, the battery management system monitors the working status of the vehicle energy distribution system in real time. If it is detected that the working status of the vehicle energy distribution system is abnormal, the lithium plating detection mode is stopped in time.

[0053] The present application makes full use of the advantages of multiple power sources of hybrid electric vehicles, and can achieve constant low-rate discharge of automotive lithium batteries and lithium plating detection of automotive lithium batteries by controlling the energy distribution of the entire vehicle without affecting the normal use of the vehicle.

[0054] In step S3, the battery management system collects the voltage of the automotive lithium battery during the discharge process in the lithium plating detection mode in real time, and calculates the minimum value of the lithium plating characteristic parameter dV / dQ (battery voltage change per unit discharge capacity) in the time interval through the lithium plating characteristic parameter calculation module, and uploads it to the cloud platform.

[0055] That is, this application does not require additional sensors, and can use the existing sampling and computing resources of the battery management system, which is low-cost and highly practical.

[0056] See the instruction manual Figure 3 , after receiving the lithium battery lithium deposition characteristic parameter dV / dQ uploaded by the battery management system, the cloud platform constructs the current differential voltage curve of the discharge process after removing the abnormal value (the horizontal axis is the discharge power, the vertical axis is dV / dQ). If the current differential voltage curve is monotonically increasing, it is confirmed that the automotive lithium battery has not undergone lithium deposition; if the current differential voltage curve is first increasing, then decreasing, and then increasing, it means that the automotive lithium battery has undergone lithium deposition. And the first trough position in the current differential voltage curve corresponds to the end of the lithium battery stripping process inside the battery, and the discharge capacity at this trough position corresponds to the amount of reversible lithium metal in the lithium deposition reaction; further, combined with the historical data stored in the cloud platform, the discharge capacity corresponding to the first trough position of the historical differential voltage curve is obtained through the historical data, and the difference in discharge capacity between the two is the reduction in reversible lithium, that is, the newly added lithium deposition capacity in this stage, and the formula is as follows: lithium deposition capacity = the first discharge capacity corresponding to the first trough position of the current differential voltage curve - the second discharge capacity corresponding to the first trough position of the historical differential voltage curve.

[0057] In one embodiment, it is assumed that the cloud platform recognizes that in the lithium deposition detection mode of the first lithium battery of the hybrid vehicle lithium battery pack, the discharge capacity corresponding to the first differential voltage trough position of the current differential voltage curve is 10AH, and the discharge capacity corresponding to the first differential voltage trough position of the historical differential voltage curve is 17AH; in the lithium deposition detection mode of the second lithium battery, the discharge capacity corresponding to the first differential voltage trough position of the current differential voltage curve is 8AH, and the discharge capacity corresponding to the first differential voltage trough position of the historical differential voltage curve is 13AH, then the lithium deposition capacity of the lithium battery is: the lithium deposition capacity of the first lithium battery = 17-10 = 7AH; the lithium deposition capacity of the second lithium battery = 13-8 = 5AH.

[0058] This application utilizes the advantages of high computing power and strong storage capacity of the cloud platform, and combines historical data to evaluate the lithium plating capacity of automotive lithium batteries, thereby avoiding deviations in lithium plating identification of the battery management system.

[0059] In addition, in this application, the cloud platform sends the lithium battery lithium deposition status and the maximum lithium deposition capacity of all cells in the battery pack to the battery management system. If lithium deposition occurs in the automotive lithium battery, the charging rate is reduced under fast charging and low-temperature charging conditions to deal with lithium deposition. Among them, charging current = charging rate * (rated capacity - maximum lithium deposition capacity).

[0060] In one embodiment, assuming that the rated capacity of the automotive lithium battery is 153AH, and the charging rate under fast charging conditions at 25°C is 2C, if the cloud platform informs the battery management system that lithium plating has occurred in the automotive lithium battery and the maximum lithium plating capacity of the battery cell is 7AH, then the charging current = charging rate * (rated capacity - maximum lithium plating capacity) = 2*(153-7) = 292A; if the cloud platform informs the battery management system that lithium plating has not occurred in the automotive lithium battery, then the charging current = charging rate * (rated capacity - maximum lithium plating capacity) = 2*(153-0) = 306A.

[0061] The present application provides a method for identifying lithium plating in automotive lithium batteries. By confirming the lithium plating detection mode of hybrid electric vehicle lithium batteries, the energy distribution system, thermal management system and battery management system work together to achieve constant low-rate discharge of automotive lithium batteries at an appropriate temperature. The battery management system calculates the minimum dV / dQ value in real time over a period of time and uploads it to the cloud platform. The cloud platform constructs a differential voltage curve of the discharge process. The discharge capacity corresponding to the trough position of the first curve is the amount of reversible lithium metal in the lithium plating reaction. The capacity difference between the trough position of the first curve and the capacity corresponding to the trough position of the historical differential voltage curve is the reduction of reversible lithium, that is, the newly added lithium plating capacity at this stage. If lithium plating is detected, the lithium plating can be dealt with by reducing the charging rate under low-temperature charging and other working conditions, thereby achieving stable and safe operation of hybrid electric vehicles.

[0062] As the instruction manual Figure 4As shown, the present application also provides a lithium plating identification device for a vehicle lithium battery, which is applied to a hybrid vehicle, wherein the hybrid vehicle includes a vehicle energy distribution system, a battery management system and a cloud platform, wherein the battery management system includes a lithium plating detection mode setting module, a power system power control module, a lithium plating characteristic parameter calculation module, a lithium plating parameter cloud platform interaction module and a lithium plating response module; the identification device includes:

[0063] A setting module 401 is used to set the lithium deposition identification working condition of the vehicle lithium battery based on the lithium deposition detection mode setting module, and start the lithium deposition detection mode when the battery management system recognizes that the vehicle lithium battery meets the lithium deposition identification working condition; wherein the lithium deposition identification working condition includes the temperature range of the vehicle lithium battery after it is fully charged;

[0064] A control module 402 is used to generate a constant low-rate discharge request based on the power system power control module and send it to the vehicle energy distribution system, and the vehicle energy distribution system maintains the vehicle lithium battery to discharge within the temperature range through energy distribution according to the constant low-rate discharge request;

[0065] The calculation module 403 is used to calculate the lithium deposition characteristic parameters of the vehicle lithium battery during constant low-rate discharge in real time based on the lithium deposition characteristic parameter calculation module, and upload them to the cloud platform through the lithium deposition parameter cloud platform interaction module. The cloud platform calculates the lithium deposition capacity of the vehicle lithium battery based on the received lithium deposition characteristic parameters and in combination with historical data, and sends them to the battery management system.

[0066] In some embodiments, the setting module 401 turns on the lithium deposition detection mode when the battery management system identifies that the vehicle lithium battery meets the lithium deposition identification working condition, including: generating a lithium deposition detection mode turn-on prompt when the battery management system identifies that the vehicle lithium battery meets the lithium deposition identification working condition; within a set time, if a lithium deposition detection mode turn-on acceptance instruction is received, turning on the lithium deposition detection mode; if no lithium deposition detection mode turn-on acceptance instruction is received, giving up turning on the lithium deposition detection mode.

[0067] In some embodiments, the control module 402 is composed of the whole vehicle energy distribution system, which maintains the discharge of the vehicle lithium battery within the temperature range through energy distribution according to the constant small rate discharge request, including: real-time monitoring of the working status of the whole vehicle energy distribution system based on the battery management system; if the working status of the whole vehicle energy distribution system is abnormal, stopping the lithium plating detection mode.

[0068] In some embodiments, the lithium deposition characteristic parameter is the minimum value of the battery voltage change value per unit discharge capacity within a time period, and the calculation module 403 calculates the lithium deposition capacity of the vehicle lithium battery by the cloud platform according to the received lithium deposition characteristic parameter and in combination with historical data, including: constructing a current differential voltage curve according to the received lithium deposition characteristic parameter; judging whether the vehicle lithium battery has lithium deposition according to the change trend of the current differential voltage curve; if it is judged that the vehicle lithium battery has lithium deposition, obtaining the first discharge capacity corresponding to the first trough position of the current differential voltage curve, and obtaining the second discharge capacity corresponding to the first trough position of the historical differential voltage curve through historical data; calculating the difference between the first discharge capacity and the second discharge capacity to obtain the lithium deposition capacity within the time period. Wherein, if the current differential voltage curve is monotonically increasing, it is judged that the vehicle lithium battery has not undergone lithium deposition; if the current differential voltage curve first increases, then decreases, and then increases, it is judged that the vehicle lithium battery has undergone lithium deposition.

[0069] In some embodiments, the device further comprises:

[0070] The regulating module is used to determine the maximum lithium deposition capacity from the lithium deposition capacities of all the lithium deposition capacities of the lithium deposition batteries for the vehicle if it is determined that lithium deposition occurs in the lithium deposition battery for the vehicle; and to regulate the charging current based on the maximum lithium deposition capacity, the rated capacity and the charging rate of the lithium deposition battery for the vehicle.

[0071] The present application provides a lithium deposition identification device for a vehicle lithium battery. The device sets the lithium deposition identification working condition of the vehicle lithium battery based on the lithium deposition detection mode setting module through a setting module, and turns on the lithium deposition detection mode when the battery management system identifies that the vehicle lithium battery meets the lithium deposition identification working condition; generates a constant small rate discharge request based on the power system power control module through a control module, and sends it to the whole vehicle energy distribution system, and the whole vehicle energy distribution system maintains the vehicle lithium battery to discharge within the temperature range through energy distribution according to the constant small rate discharge request; calculates the lithium deposition characteristic parameters of the vehicle lithium battery in real time during constant small rate discharge based on the lithium deposition characteristic parameter calculation module through a calculation module, and uploads them to the cloud platform through the lithium deposition parameter cloud platform interaction module, and the cloud platform calculates the lithium deposition capacity of the vehicle lithium battery based on the received lithium deposition characteristic parameters and in combination with historical data, and sends it to the battery management system. On the one hand, the power source advantages of hybrid vehicles are fully utilized, and the energy distribution of the vehicle energy distribution system is used to achieve a constant low-rate discharge of automotive lithium batteries at an appropriate temperature. The characteristic parameters of lithium plating are obtained through the battery management system without adding additional sensors, thereby reducing costs. On the other hand, the vehicle-cloud collaboration method is adopted to analyze the characteristic parameters of lithium plating in real time, confirm the lithium plating situation and respond, thereby ensuring the stable and safe operation of the vehicle.

[0072] Based on the same concept of the present invention, the specification is attached Figure 5 As shown, the structure of an electronic device 500 provided in an embodiment of the present application includes: at least one processor 501, at least one network interface 504 or other user interface 503, a memory 505, and at least one communication bus 502. The communication bus 502 is used to realize the connection and communication between these components. The electronic device 500 optionally includes a user interface 503, including a display (for example, a touch screen, LCD, CRT, holographic imaging (Holographic) or projection (Projector), etc.), a keyboard or a pointing device (for example, a mouse, a trackball (trackball), a touch pad or a touch screen, etc.).

[0073] The memory 505 may include a read-only memory and a random access memory, and provides instructions and data to the processor 501. A portion of the memory 505 may also include a non-volatile random access memory (NVRAM).

[0074] In some implementations, the memory 505 stores the following elements, executable modules or data structures, or a subset thereof, or an extended set thereof:

[0075] Operating system 5051, including various system programs, used to implement various basic services and process hardware-based tasks;

[0076] The application module 5052 includes various application programs, such as a launcher, a media player, a browser, etc., which are used to implement various application services.

[0077] In an embodiment of the present application, by calling the program or instructions stored in the memory 505, the processor 501 is used to execute steps in a method for identifying lithium plating in a vehicle lithium battery, which can accurately detect and respond to lithium plating in a hybrid vehicle lithium battery, thereby ensuring stable and safe operation of the vehicle.

[0078] The present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps in the method for identifying lithium deposition in a lithium battery for a vehicle are executed.

[0079] Specifically, the storage medium can be a general storage medium, such as a mobile disk, a hard disk, etc. When the computer program on the storage medium is run, the above-mentioned vehicle lithium battery lithium plating identification method can be executed.

[0080] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0081] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0082] In addition, each functional unit in the embodiments provided in the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0083] If the function is implemented in the form of a business function unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes a number of instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0084] Finally, it should be noted that the above embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the aforementioned embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the aforementioned embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes 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. They should all be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for identifying lithium deposition in a lithium battery for a vehicle, characterized in that: Applied to hybrid electric vehicles, the hybrid electric vehicles include a vehicle energy distribution system, a battery management system and a cloud platform, the battery management system includes a lithium deposition detection mode setting module, a power system power control module, a lithium deposition characteristic parameter calculation module, a lithium deposition parameter cloud platform interaction module and a lithium deposition response module; the identification method includes the following steps: The lithium deposition identification working condition of the vehicle lithium battery is set based on the lithium deposition detection mode setting module, and when the battery management system identifies that the vehicle lithium battery meets the lithium deposition identification working condition, the lithium deposition detection mode is turned on; wherein the lithium deposition identification working condition includes the temperature range of the vehicle lithium battery after it is fully charged; Generate a constant low-rate discharge request based on the power system power control module, and send it to the whole vehicle energy distribution system, and the whole vehicle energy distribution system maintains the vehicle lithium battery to discharge within the temperature range through energy distribution according to the constant low-rate discharge request; Based on the lithium deposition characteristic parameter calculation module, the lithium deposition characteristic parameters of the automotive lithium battery during constant low-rate discharge are calculated in real time, and uploaded to the cloud platform through the lithium deposition parameter cloud platform interaction module. The cloud platform calculates the lithium deposition capacity of the automotive lithium battery based on the received lithium deposition characteristic parameters and in combination with historical data, and sends it to the battery management system.

2. A method for identifying lithium deposition in a lithium battery for a vehicle according to claim 1, characterized in that: When the battery management system identifies that the vehicle lithium battery meets the lithium plating identification working condition, starting the lithium plating detection mode includes the following steps: When the battery management system identifies that the vehicle lithium battery meets the lithium plating identification working condition, a lithium plating detection mode start prompt is generated; Within the set time, if the lithium deposition detection mode start acceptance instruction is received, the lithium deposition detection mode is started; if the lithium deposition detection mode start acceptance instruction is not received, the lithium deposition detection mode is abandoned.

3. A method for identifying lithium deposition in a lithium battery for a vehicle according to claim 2, characterized in that: The whole vehicle energy distribution system maintains the vehicle lithium battery to discharge within the temperature range through energy distribution according to the constant low rate discharge request, including the following steps: Based on the battery management system, real-time monitoring of the working status of the vehicle energy distribution system; If the working state of the vehicle energy distribution system is abnormal, the lithium plating detection mode is stopped.

4. A method for identifying lithium deposition in a lithium battery for a vehicle according to claim 3, characterized in that: The lithium deposition characteristic parameter is the minimum value of the battery voltage change value per unit discharge capacity within a time period; the cloud platform calculates the lithium deposition capacity of the vehicle lithium battery according to the received lithium deposition characteristic parameter and in combination with historical data, including the following steps: Constructing a current differential voltage curve according to the received lithium deposition characteristic parameters; Determining whether lithium deposition occurs in the vehicle lithium battery according to the change trend of the current differential voltage curve; If it is determined that lithium deposition occurs in the vehicle lithium battery, a first discharge capacity corresponding to a first trough position of the current differential voltage curve is obtained, and a second discharge capacity corresponding to a first trough position of the historical differential voltage curve is obtained through historical data; The difference between the first discharge capacity and the second discharge capacity is calculated to obtain the lithium deposition capacity in the time period.

5. A method for identifying lithium deposition in a lithium battery for a vehicle according to claim 4, characterized in that: The step of judging whether lithium deposition occurs in the vehicle lithium battery according to the change trend of the current differential voltage curve comprises the following steps: If the current differential voltage curve increases monotonically, it is determined that lithium deposition does not occur in the vehicle lithium battery; If the current differential voltage curve first increases, then decreases, and then increases again, it is determined that lithium deposition occurs in the automotive lithium battery.

6. A method for identifying lithium deposition in a lithium battery for a vehicle according to claim 5, characterized in that: The method further comprises the following steps: If it is determined that lithium plating occurs in the automotive lithium battery, the maximum lithium plating capacity is determined from the lithium plating capacities of all automotive lithium batteries; The charging current is adjusted based on the maximum lithium plating capacity, the rated capacity and the charging rate of the vehicle lithium battery.

7. A method for identifying lithium deposition in a lithium battery for a vehicle according to claim 6, characterized in that: in, Set the temperature range of the fully charged automotive lithium battery to 10°C to 35°C.

8. A lithium deposition identification device for a vehicle lithium battery, characterized in that: Applied to hybrid electric vehicles, the hybrid electric vehicles include a vehicle energy distribution system, a battery management system and a cloud platform, the battery management system includes a lithium deposition detection mode setting module, a power system power control module, a lithium deposition characteristic parameter calculation module, a lithium deposition parameter cloud platform interaction module and a lithium deposition response module; the identification device includes: A setting module, used to set the lithium deposition identification working condition of the vehicle lithium battery based on the lithium deposition detection mode setting module, and start the lithium deposition detection mode when the battery management system recognizes that the vehicle lithium battery meets the lithium deposition identification working condition; wherein the lithium deposition identification working condition includes the temperature range of the vehicle lithium battery after it is fully charged; A control module, configured to generate a constant low-rate discharge request based on the power system power control module, and send the request to the vehicle energy distribution system, so that the vehicle energy distribution system maintains the discharge of the vehicle lithium battery within the temperature range through energy distribution according to the constant low-rate discharge request; A calculation module is used to calculate the lithium deposition characteristic parameters of the vehicle lithium battery during constant low-rate discharge in real time based on the lithium deposition characteristic parameter calculation module, and upload them to the cloud platform through the lithium deposition parameter cloud platform interaction module. The cloud platform calculates the lithium deposition capacity of the vehicle lithium battery based on the received lithium deposition characteristic parameters and in combination with historical data, and sends them to the battery management system.

9. An electronic device, characterized in that: include: A processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate via the bus, and when the machine-readable instructions are executed by the processor, the steps of the method for identifying lithium deposition in a lithium battery for a vehicle as described in any one of claims 1 to 7 are performed.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method for identifying lithium deposition in a lithium battery for a vehicle as described in any one of claims 1 to 7 are executed.

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