Universe rhythm fast charge control method for multi-system power battery

Abstract

The invention relates to the technical field of power battery charging control, and discloses a global rhythm fast charging control method for a multi-system power battery, which comprises the following steps of: performing pre-charging activation on the battery through small current, eliminating standing polarization and establishing stable voltage response; the charging current is gradually increased in the safe current interval of the battery, so that the battery enters a stable state capable of accepting high-power charging; main fast charging is executed in a constant-current or constant-power mode, and the charging upper limit is dynamically restrained according to the real-time state of the battery; and the charging current is reduced, so that the battery voltage stably approaches the target cut-off voltage, and side reaction and lithium precipitation are inhibited. By constructing a fixed irreversible five-stage charging rhythm of battery awakening, current raising, fast charging master control, voltage convergence and full charging, a universal and forced logic framework is provided for the charging process, logic switching disorder is avoided, and the risk of lithium precipitation and deposition is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of power battery charging control technology, specifically to a method for full-domain rhythmic fast charging control of multi-system power batteries. Background Technology

[0002] With the popularization of electric vehicles and energy storage systems, the fast charging capability of power batteries has become a key requirement. However, the diversity of battery chemistry systems leads to significant differences in their electrochemical characteristics, which poses a serious challenge to the development of a universal, efficient and safe fast charging strategy.

[0003] Existing fast charging solutions are mostly designed for single-chemical battery systems, which have poor versatility. Conventional constant current and constant voltage charging at high rates can easily cause lithium plating on the negative electrode, electrolyte decomposition, polarization accumulation, and abnormal temperature rise, which seriously affect battery cycle life and safety. Some fast charging technologies rely on dedicated hardware structures or specific cell formulations, which limit the applicable scenarios and have high modification costs. Segmented charging solutions have not established a strict and irreversible stage timing and electrochemical inflection point switching mechanism, and the stage switching is highly random, making it difficult to achieve a balance between safety and long cycle life at 4C to 10C ultra-fast charging rates. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for full-domain rhythmic fast charging control of multi-system power batteries, which solves at least one of the problems mentioned in the background technology.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for full-range rhythmic fast charging control of multi-system power batteries, comprising the following steps: S1. Pre-charge and activate the battery with a small current to eliminate static polarization and establish a stable voltage response; S2. Gradually increase the charging current within the battery's safe current range to bring the battery into a stable state where it can accept high-power charging. S3. Perform main fast charging in constant current or constant power mode, and dynamically constrain the upper limit of charging according to the real-time status of the battery. S4. Reduce the charging current to make the battery voltage steadily approach the target cutoff voltage and suppress side reactions and lithium plating; S5. A small current is used to fully charge the battery, eliminating polarization rebound and achieving precise full charging. The switching of each stage is based on the inflection point of the battery's electrochemical state. The charging process consists of five stages, S1, S2, S3, S4, and S5, executed in a fixed sequence, and the order of each stage is irreversible and cannot be omitted.

[0006] Preferably, in step S1, a small current of 0.1C to 0.3C is used to wake up the battery for 5 to 15 minutes. In step S2, the charging current is gradually increased to 2C to 4C when the current is raised. In step S3, the charging current during the fast charging main control stage is 4C to 10C.

[0007] Preferably, the charging current is 0.5C to 1C during the voltage convergence phase in step S4, and a current of 0.05C to 0.1C is used when fully charging the battery in step S5, lasting for 10 to 30 minutes.

[0008] Preferably, the power battery includes one or more of lithium iron phosphate, ternary lithium, solid-state, semi-solid-state, sodium-ion, and magnesium-ion batteries.

[0009] Preferably, the control method operates on any one of the following devices: battery management system (BMS), vehicle controller, DC fast charging pile, and energy storage converter, or multiple devices work together to achieve full-domain control.

[0010] Preferably, the multi-device collaboration between the DC fast charging pile and the BMS specifically includes: the DC fast charging pile collects battery voltage, current, temperature, and impedance data in real time and identifies the inflection point of the electrochemical state, transmits the inflection point signal to the BMS, and the BMS issues charging current commands for each stage to the DC fast charging pile according to the inflection point signal, and the DC fast charging pile performs dynamic current adjustment to achieve full-domain rhythmic fast charging control.

[0011] Preferably, the electrochemical state inflection point includes one or more of the following: polarization inflection point, impedance inflection point, and temperature rise inflection point.

[0012] Preferably, during phase switching, a multivariate fusion inflection point cross-validation and switching decision mechanism is implemented, including the following steps: S1: When it is necessary to determine whether to switch to the next stage, synchronously collect and analyze the battery's polarization voltage, impedance, and temperature rise data; S2: Based on the collected data, identify at least two different types of electrochemical state inflection points in parallel or sequentially; S3: Only when the inflection points of at least two different types of electrochemical states are identified and confirmed, a valid stage switching instruction is generated to trigger the switch from the current stage to the next stage.

[0013] Preferably, the at least two different types of electrochemical state inflection points mentioned in step S2 are any two or more combinations of polarization inflection point, impedance inflection point, and temperature rise inflection point.

[0014] Preferably, the decision logic for generating a valid stage switching instruction in step S3 specifically includes: performing a logical AND operation or a logical combination operation that conforms to preset rules on the identified multiple electrochemical state inflection point signals, and outputting a switching instruction when the operation result is true.

[0015] This invention provides a method for full-range rhythmic fast charging control of multi-system power batteries. It has the following beneficial effects: 1. This invention provides a universal and mandatory logical framework for the charging process by constructing a fixed and irreversible five-stage charging rhythm: battery wake-up - current rise - fast charging master control - voltage convergence - full charge. This avoids switching logic confusion and significantly reduces the risk of lithium plating and deposition.

[0016] 2. The electrochemical state inflection point inside the battery of this invention serves as the sole basis for switching between stages, replacing the traditional external triggering method based on fixed voltage or time thresholds. This allows the stage switching to accurately match each node of the battery from polarization establishment, interface activation, rapid response to saturation. Thus, while pursuing high-rate charging of 4C to 10C, it can effectively avoid risks such as overcharging, lithium plating, and overheating caused by switching too early or too late, fundamentally improving the safety of the ultra-fast charging process.

[0017] 3. This invention defines a universal charging process applicable to multiple electrochemical systems, enabling the same control logic to be adapted to batteries with different intrinsic characteristics. This achieves universal control of multiple power batteries in ultra-fast charging scenarios and reduces the complexity of solution development and adaptation.

[0018] 4. This invention forms a complete solution from state perception and intelligent decision-making to precise execution through a data acquisition module, an inflection point identification and cross-validation module, a rhythm stage control module, and a current output control module. This not only ensures the feasibility of the method on various hardware platforms such as vehicle-mounted BMS, DC fast charging piles, or vehicle-pile collaboration, but also enables the fast charging process to have both deterministic framework constraints and dynamic adaptability based on real-time state, achieving an optimized balance between charging speed, safety, and battery life.

[0019] 5. By introducing a multi-variable fusion inflection point cross-validation and switching decision mechanism, this invention constitutes a highly reliable decision logic, which significantly improves the fault tolerance capability of single inflection point identification that may be misjudged due to signal noise or instantaneous disturbances. It ensures that each stage advancement is a robust decision based on the collaborative evolution of multiple battery states, thereby enhancing the robustness and accuracy of the entire charging rhythm execution. Attached Figure Description

[0020] Figure 1 This is a flowchart of the five-stage global rhythm fast charging process of the present invention; Figure 2 This is a schematic diagram of the stage switching logic of the electrochemical inflection point in this invention; Figure 3 This is a schematic diagram of the vehicle-pile collaborative control architecture of the present invention; Figure 4This is a schematic diagram of the multivariate fusion verification logic of the present invention. Detailed Implementation

[0021] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please see the appendix Figure 1 This invention provides a method for full-domain rhythmic fast charging control of multi-system power batteries, comprising the following steps: S1. Pre-charge and activate the battery with a small current to eliminate static polarization and establish a stable voltage response; S2. Gradually increase the charging current within the battery's safe current range to bring the battery into a stable state where it can accept high-power charging. S3. Perform main fast charging in constant current or constant power mode, and dynamically constrain the upper limit of charging according to the real-time status of the battery. S4. Reduce the charging current to make the battery voltage steadily approach the target cutoff voltage and suppress side reactions and lithium plating; S5. A small current is used to fully charge the battery, eliminating polarization rebound and achieving precise full charging. The switching of each stage is based on the inflection point of the battery's electrochemical state. The charging process is executed in a fixed sequence of five stages: S1, S2, S3, S4, and S5. The order of each stage is irreversible and cannot be omitted. In step S1, a small current of 0.1C to 0.3C is used to wake up the battery for 5 to 15 minutes. In step S2, the charging current is gradually increased to 2C to 4C when the current is raised. In step S3, the charging current is 4C to 10C during the fast charging main control stage. In step S4, the charging current is 0.5C to 1C during the voltage convergence stage. In step S5, a current of 0.05C to 0.1C is used to fully charge the battery for 10 to 30 minutes.

[0023] Specifically, the charging device pre-charges the power battery with a small current ranging from 0.1C to 0.3C, and the duration of the pre-charging operation is controlled within 5 to 15 minutes. This gentle current activates the battery after it has been left to rest, further waking it up and balancing the ion concentration distribution within the battery. This eliminates concentration polarization caused by resting and establishes a stable electrode-electrolyte interface, providing a predictable voltage response basis for subsequent high-current charging. Once the battery wake-up phase is complete and the switching conditions are met, the system controls the charging current to gradually increase within the safe current range allowed by the battery itself, starting from the current value of the wake-up phase and following a predetermined rate curve. The target value is set within the 2C to 4C rate range to smoothly transition the battery from its post-awakening stable state to a quasi-steady state capable of withstanding higher power charging. This further optimizes the electrochemical reaction interface, reduces the risk of overpotential surges during high-current steps, and completes the current ramp-up phase. After meeting the corresponding switching conditions, the system enters the high-power energy injection phase. In this phase, the charging system controls the charging device to rapidly charge the battery with a constant current or corresponding constant power within the 4C to 10C range. Simultaneously, the system monitors the battery's terminal voltage and temperature in real time and dynamically calculates and constrains the maximum allowable charging current or power for this phase based on the battery's voltage safety upper limit and temperature safety threshold. To ensure the charging process remains within the battery's absolute safety window, when the fast charging control phase reaches a point where the battery's terminal voltage or state of charge approaches its charging cutoff limit and meets the corresponding switching conditions, the system actively reduces the charging current to the range of 0.5C to 1C. This further allows the battery's terminal voltage to rise smoothly and controllably at a lower current, eventually approaching the preset charging cutoff voltage. The current convergence process helps suppress side reactions at the end of charging and the rapid deposition and lithium plating tendency of lithium ions on the negative electrode surface, thus improving charging safety. During the voltage convergence phase, after the battery voltage reaches the charging cutoff voltage and meets the final switching conditions, the system controls the charging device to replenish the battery with an extremely small current ranging from 0.05C to 0.1C. The charging time is controlled between 10 and 30 minutes. By using a small current to eliminate the voltage drop caused by ohmic polarization and concentration polarization, the active materials inside the battery can fully react, achieving precise full charging of the state of charge and improving the consistency between different battery cells. The system includes a data acquisition module, a rhythm control module, and a charging execution module. The data acquisition module is used to collect the voltage, current, and temperature signals of the power battery in real time. The rhythm control module has a built-in logic sequence of five stages of rhythm and judges the stage switching conditions based on the data input from the data acquisition module, outputting the charging current command corresponding to the current stage. The charging execution module receives the current command from the rhythm control module and controls the power devices to output the corresponding current to the power battery.

[0024] Furthermore, the power battery includes one or more of the following: lithium iron phosphate, ternary lithium, solid-state, semi-solid-state, sodium-ion, and magnesium-ion batteries.

[0025] Specifically, Example 1: For the lithium iron phosphate battery wake-up phase, a 0.2C current is used for 10 minutes; the current rise phase is linearly increased to 3C; the fast charging main control phase uses 6C constant current charging; the voltage convergence phase uses 0.8C current; and the full charge phase uses 0.08C current for 20 minutes.

[0026] Example 2: For the ternary lithium battery vehicle-pile coordinated fast charging battery wake-up stage, a current of 0.15C is used for 8 minutes; the current rise stage is increased to 2.5C; the fast charging main control stage uses 8C constant power charging; the voltage convergence stage uses 0.7C current; and the full charge stage uses 0.05C current for 30 minutes.

[0027] Example 3: For sodium-ion batteries and energy storage systems, the wake-up phase of fast charging uses a 0.3C current for 6 minutes; the current rise phase is increased to 4C; the fast charging main control phase uses a 10C constant current charging; the voltage convergence phase uses a 1C current; and the full charge phase uses a 0.1C current for 15 minutes.

[0028] Please see the appendix Figure 2 and attached Figure 3 The control method operates on any device in the Battery Management System (BMS), vehicle controller, DC fast charging pile, and energy storage converter, or multiple devices work together to achieve full-domain control. The multi-device collaboration specifically includes the collaboration between the DC fast charging pile and the BMS: the DC fast charging pile collects battery voltage, current, temperature, and impedance data in real time and identifies the inflection point of the electrochemical state, transmits the inflection point signal to the BMS, and the BMS issues charging current commands for each stage to the DC fast charging pile according to the inflection point signal. The DC fast charging pile performs dynamic current adjustment to achieve full-domain rhythmic fast charging control.

[0029] Specifically, the input of the data acquisition module is first connected to the voltage, current, and temperature sensors of the power battery. Its output is connected to the input of the inflection point identification and cross-validation module via a data bus. The output of the inflection point identification and cross-validation module is then connected to the input of the rhythm phase control module, whose output is connected to the input of the current output control module. The output of the current output control module is then connected to the control terminal of the charging actuator, which includes an on-board charger, a DC-DC converter, or a power conversion unit within a DC fast charging pile. The data acquisition module consists of a signal conditioning circuit and an analog-to-digital converter. This system is designed for real-time acquisition of the battery's terminal voltage, charging current, and battery temperature, converting analog signals into digital signals. The inflection point identification and cross-validation module is implemented by a microprocessor unit and its stored algorithm program. This module receives real-time data from the data acquisition module and includes embedded polarization inflection point identification, impedance inflection point identification, and temperature rise inflection point identification subroutines. It also includes a fusion decision subroutine. The logic is that when a stage switching is required, it receives Boolean output signals from at least two different inflection point identification subroutines and performs a logical AND operation. The fusion decision subroutine is executed only when all input Boolean signals are true. The program outputs a high-level switching enable signal to the rhythm stage control module. The rhythm stage control module is implemented through a state machine or microcontroller program logic, internally storing a fixed sequence of logic for five stages: battery wake-up, current boost, fast charging master control, voltage convergence, and full charge. The input of the rhythm stage control module receives the switching enable signal from the inflection point identification and cross-validation module. During each charging stage, the rhythm stage control module continuously outputs the current reference command corresponding to that stage to the current output control module. The internal state of the rhythm stage control module only changes when it receives the switching enable signal. The current output control module, implemented by a digital controller and its drive circuit, transitions from the current stage to the next and updates the output current reference command. It receives the current reference command from the rhythm stage control module and controls the power switching devices in the charging actuator using pulse width modulation or analog control, ensuring the actual output charging current follows the current reference command. During power-on initialization, the rhythm stage control module first sets its state to the battery wake-up stage and sends a first current command corresponding to this stage to the current output control module. The current output control module then controls the charging actuator to output the current. During the battery wake-up phase, the data acquisition module continuously collects the battery's voltage U, current I, and temperature T. The inflection point identification and cross-validation module executes polarization inflection point and impedance inflection point identification algorithms in parallel. The polarization inflection point identification algorithm continuously calculates the polarization voltage change rate. ,when Continuously below the set threshold Time of arrival When the polarization inflection point is detected, an output signal is generated. If true, the impedance inflection point identification algorithm continuously calculates the impedance change trend. ,when Continuously below the set threshold Time of arrival When the impedance inflection point is detected, the output signal is activated. If true, further fusion judgment and phase switching are performed. When the duration of the wake-up phase reaches the minimum set value... Subsequently, the fusion decision subroutine of the inflection point identification and cross-validation module reads... and Signals, combined with the decision subroutine to perform logical operations: ; If the calculation result is true, a high-level switching enable signal is sent to the rhythm stage control module. Upon receiving this signal, the internal state of the rhythm stage control module immediately changes from the battery wake-up stage to the current rise stage. After entering the current rise stage, it issues the second current command curve corresponding to this stage to the current output control module. Then, the charging actuator is controlled by the current output control module to output the current from according to The trajectory was improved to the target value. The process then repeats steps S2 through S4. During the current rise phase, the inflection point identification and cross-validation module monitors and verifies the inflection point combination used to switch to the fast charging main control phase. In the subsequent fast charging main control phase and voltage convergence phase, it monitors and verifies the specific inflection point combination required to switch to the next phase. Each successful verification triggers a state transition in the rhythm phase control module and an instruction update in the current output control module, until the full charging phase ends and the system shuts down its output. The data acquisition module and current output control module can also be located within the DC fast charging pile, forming a pile-end control unit. The inflection point identification and cross-validation module and the rhythm phase control module can be located within the vehicle's on-board battery management system, forming a vehicle-to-everything (V2X) control unit. The charging pile control unit and the vehicle-side control unit interact with each other and transmit control commands through the vehicle charging communication interface. The data acquisition module of the charging pile control unit collects battery voltage, current, and temperature data and sends them to the vehicle-side control unit through the communication interface. The inflection point identification and cross-validation module of the vehicle-side control unit performs inflection point identification and fusion decision and informs the rhythm stage control module of the result. At this time, the rhythm stage control module generates a charging command containing the target current value based on the current stage and the decision result, and sends it to the charging pile control unit through the communication interface. The current output control module of the charging pile control unit parses the command and controls the power module of the fast charging pile to output the corresponding current.

[0030] Please see the appendix Figure 2 Furthermore, the electrochemical state inflection point includes one or more of the following: polarization inflection point, impedance inflection point, and temperature rise inflection point.

[0031] Specifically, the data acquisition module synchronously acquires the real-time terminal voltage U(t), charging current I(t), and surface temperature T(t) of the power battery. The data acquisition module sends a set of time-aligned voltage, current, and temperature data streams to the subsequent inflection point identification module for polarization inflection point identification. The polarization inflection point identification module b1 first estimates the polarization overpotential of the battery based on the battery's equivalent circuit model or by consulting the open-circuit voltage-state-of-charge correspondence table. Polarization overpotential By calculating the real-time terminal voltage U(t) and the current battery static electromotive force... The difference is: ; in, Estimated using the ampere-hour integration method, further analysis shows that when the battery is in a low-current wake-up or high-current convergence process, the internal ion concentration distribution tends to be balanced, and the rate of change of polarization overpotential will decrease, i.e., within a continuous time window... The calculated result The absolute value is consistently less than the preset threshold. When the condition is met, the polarization inflection point identification module b1 outputs a Boolean identifier signal. Setting this to logical true, for impedance inflection point identification, firstly, the impedance inflection point identification module b2 receives voltage U(t) and current I(t) data from the data acquisition module. Then, it uses time-domain or frequency-domain methods to estimate the battery impedance online. Specifically, it includes a small amplitude AC disturbance signal of a specific frequency in the charging current, and calculates the AC impedance at that frequency by calculating the ratio of the voltage response to the current disturbance. Alternatively, it uses the step change of the current and analyzes the voltage relaxation response curve to fit the battery's ohmic internal resistance and polarization resistance. Furthermore, the impedance inflection point identification module b2 calculates the impedance value's change trend over time and the impedance magnitude at a specific frequency. rate of change In a continuous time window Inside, The absolute value is consistently less than the preset threshold. When this condition is met, the impedance inflection point identification module b2 outputs a Boolean identification signal. Setting it to logical true, for the identification of the temperature rise inflection point, the temperature rise inflection point identification module b3 first receives the temperature T(t) data from the data acquisition module, and then calculates the battery's temperature rise rate. Specifically, within a continuous time window Inside, The value is consistently less than the preset threshold. When this condition is met, the temperature rise inflection point identification module b3 outputs a Boolean identifier signal. Set it to logical true. For multi-inflection point fusion, firstly, the multivariate fusion verification module c receives inflection point identification signals from modules b1, b2, and b3. , , The multivariate fusion verification module C pre-defines the fusion decision rules required for different stage transitions. These rules are logical combinations of at least two different types of inflection point signals. For a decision to switch from stage X to stage Y, its fusion decision function... : ; in, This is a multivariate fusion function, specifically in the form of a predefined Boolean logic expression, such as the decision to switch from the wake-up phase to the rise phase. One definition of a function is: ; Furthermore, when the polarization inflection point and the impedance inflection point are identified simultaneously, or when the polarization inflection point and the temperature rise inflection point are identified simultaneously, the fusion condition is satisfied, and the function... For the final switching decision function, when If the function outputs logical true, and the current stage has been running for its preset shortest time threshold, then... If the output is true, a valid stage switching instruction is generated. The multivariate fusion verification module C sends this switching instruction to the system's rhythm stage control module, triggering an irreversible stage transition. By identifying key electrochemical state inflection points inside the battery in real time and online, and making stage switching decisions based on rigorous multivariate fusion logic, the external charging rhythm is firmly bound to the actual changes in the battery's internal state.

[0032] Please see the appendix Figure 4 During phase switching, a multivariate fusion inflection point cross-validation and switching decision mechanism is implemented, including the following steps: S1: When it is necessary to determine whether to switch to the next stage, synchronously collect and analyze the battery's polarization voltage, impedance, and temperature rise data; S2: Based on the collected data, identify at least two different types of electrochemical state inflection points in parallel or sequentially; S3: Only when at least two different types of electrochemical state inflection points are identified and confirmed, a valid stage switching command is generated to trigger the switch from the current stage to the next stage; the at least two different types of electrochemical state inflection points in step S2 are any two or more combinations of polarization inflection points, impedance inflection points, and temperature rise inflection points; the decision logic for generating a valid stage switching command in step S3 specifically includes: performing a logical AND operation or a logical combination operation that conforms to preset rules on the identified multiple electrochemical state inflection point signals, and outputting a switching command when the operation result is true.

[0033] Specifically, when the charging process reaches a decision point requiring a switch to the next stage, the data acquisition module simultaneously collects a set of real-time battery status data. This set of data includes at least the data within the time window. The system collects voltage (U(t), current (I(t), and temperature) sequences (T(t)) and sends this data simultaneously to multiple parallel processing submodules within the inflection point identification and cross-validation module. Subsequently, the polarization inflection point identification submodule b1, impedance inflection point identification submodule b2, and temperature rise inflection point identification submodule b3 within the inflection point identification and cross-validation module execute their respective identification algorithms in parallel based on the received time-aligned data. Specifically, the polarization inflection point identification submodule b1 calculates the polarization overpotential based on U(t) and I(t). And determine its rate of change. Does it meet the preset polarization inflection point criterion? If so, submodule b1 outputs a Boolean signal. =1 means true, otherwise output =0 indicates a false condition. The impedance inflection point identification submodule b2 calculates the impedance characteristic value Z(t) or its changing trend based on U(t) and I(t), and determines whether it meets the preset impedance inflection point criterion. If it does, submodule b2 outputs a Boolean signal. =1 means true, otherwise output =0 indicates a false condition; the temperature rise inflection point identification submodule b3 calculates the temperature rise rate based on T(t). It then determines whether the temperature rise inflection point criterion is met. If it is met, submodule b3 outputs a Boolean signal. =1 means true, otherwise output =0 means false. For multivariate fusion validation decisions, specifically in the inflection point identification and cross-validation module, the fusion decision submodule b4 receives data from the submodule. The Boolean signal, fusion decision submodule b4, pre-stores the fusion decision rules necessary for switching from the current stage to the next stage. This rule is a Boolean logic function. Its input is The output is the final switching enable signal: Enable. ; in, It is a pre-defined logical combination expression for multiple inflection point signals. This refers to the duration of the current phase. The minimum runtime required at the current stage, for Its specific form is predefined for different stage switching. When switching from the battery wake-up stage to the current boost stage, its logical combination expression is as follows: : ; The logic function is only valid when the polarization inflection point and the impedance inflection point are identified simultaneously, or when the polarization inflection point and the temperature rise inflection point are identified simultaneously. The output of this condition is true only when the signal is received. For the transition from the fast charging main control stage to the voltage convergence stage, the logical combination expression is as follows: : ; The logic function is only valid when both the polarization inflection point and the temperature rise inflection point are identified. The output of `if` is true. The fusion decision submodule b4 calculates the result by calling the corresponding logical combination expression based on the current stage. Only when `if` is true... The calculation result is true, and the duration of the current stage is... Greater than or equal to its shortest duration At this time, submodule b4 outputs Enable=1, which is a high level. Subsequently, the Enable signal output by the fusion decision submodule b4 is sent to the rhythm stage control module. During the continuous operation of each charging stage, the rhythm stage control module maintains a current setpoint corresponding to that stage. When the rhythm stage control module detects that the Enable signal changes from 0 to 1, its internal state immediately jumps from the current stage to the predetermined next stage and updates its output current setpoint to the value corresponding to the next stage. This current setpoint is sent to the current output control module, which drives the charging actuator to change the output current, thereby completing the switching of the charging stage. This forms a complete closed loop of inflection point identification and cross-verification module - rhythm stage control module - current output control module, ensuring that the charging process strictly follows the fixed sequence of battery wake-up current raising fast charging main control voltage converging to full charge, and each advancement is triggered and verified by the coordinated changes of multiple electrochemical states inside the battery.

[0034] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for full-domain rhythmic fast charging control of multi-system power batteries, characterized in that, Includes the following steps: S1. Pre-charge and activate the battery with a small current to eliminate static polarization and establish a stable voltage response; S2. Gradually increase the charging current within the battery's safe current range to bring the battery into a stable state where it can accept high-power charging. S3. Perform main fast charging in constant current or constant power mode, and dynamically constrain the upper limit of charging according to the real-time status of the battery. S4. Reduce the charging current to make the battery voltage steadily approach the target cutoff voltage and suppress side reactions and lithium plating; S5. A small current is used to fully charge the battery, eliminating polarization rebound and achieving precise full charging. The switching of each stage is based on the inflection point of the battery's electrochemical state. The charging process consists of five stages, S1, S2, S3, S4, and S5, executed in a fixed sequence, and the order of each stage is irreversible and cannot be omitted.

2. The method for full-range rhythmic fast charging control of a multi-system power battery according to claim 1, characterized in that, In step S1, a small current of 0.1C to 0.3C is used to wake up the battery for 5 to 15 minutes. In step S2, the charging current is gradually increased to 2C to 4C when the current is raised. In step S3, the charging current during the fast charging main control stage is 4C to 10C.

3. The method for full-range rhythmic fast charging control of a multi-system power battery according to claim 1, characterized in that, In step S4, during the voltage convergence phase, the charging current is 0.5C to 1C. In step S5, when the battery is fully charged, a current of 0.05C to 0.1C is used for 10 to 30 minutes.

4. The method for full-range rhythmic fast charging control of a multi-system power battery according to claim 1, characterized in that, The power battery includes one or more of the following: lithium iron phosphate, ternary lithium, solid-state, semi-solid-state, sodium-ion, and magnesium-ion batteries.

5. The method for full-range rhythmic fast charging control of a multi-system power battery according to claim 1, characterized in that, The control method operates on any one of the following devices: battery management system (BMS), vehicle controller, DC fast charging pile, and energy storage converter, or multiple devices work together to achieve full-domain control.

6. The method for full-range rhythmic fast charging control of a multi-system power battery according to claim 5, characterized in that, The multi-device collaboration, specifically the collaboration between the DC fast charging pile and the BMS, includes: the DC fast charging pile collects battery voltage, current, temperature, and impedance data in real time and identifies the inflection point of the electrochemical state, transmits the inflection point signal to the BMS, and the BMS issues charging current commands for each stage to the DC fast charging pile according to the inflection point signal. The DC fast charging pile performs dynamic current adjustment to achieve full-domain rhythmic fast charging control.

7. The method for full-range rhythmic fast charging control of a multi-system power battery according to claim 1, characterized in that, The electrochemical state inflection point includes one or more of the following: polarization inflection point, impedance inflection point, and temperature rise inflection point.

8. The method for full-range rhythmic fast charging control of a multi-system power battery according to claim 1, characterized in that, During phase switching, a multivariate fusion inflection point cross-validation and switching decision mechanism is implemented, including the following steps: S1: When it is necessary to determine whether to switch to the next stage, synchronously collect and analyze the battery's polarization voltage, impedance, and temperature rise data; S2: Based on the collected data, identify at least two different types of electrochemical state inflection points in parallel or sequentially; S3: Only when the inflection points of at least two different types of electrochemical states are identified and confirmed, a valid stage switching instruction is generated to trigger the switch from the current stage to the next stage.

9. The method for full-range rhythmic fast charging control of a multi-system power battery according to claim 8, characterized in that, The at least two different types of electrochemical state inflection points mentioned in step S2 are any two or more combinations of polarization inflection point, impedance inflection point, and temperature rise inflection point.

10. The method for full-range rhythmic fast charging control of a multi-system power battery according to claim 8, characterized in that, The decision logic for generating a valid stage switching instruction in step S3 specifically includes: performing a logical AND operation or a logical combination operation that conforms to preset rules on the identified multiple electrochemical state inflection point signals, and outputting a switching instruction when the operation result is true.

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