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CN-121989752-A - Global rhythm fast charging control method for multi-system power battery

CN121989752ACN 121989752 ACN121989752 ACN 121989752ACN-121989752-A

Abstract

The invention relates to the technical field of power battery charging control, and discloses a full-domain rhythm fast charging control method of a multi-system power battery, which comprises the steps of pre-charging and activating the battery through small current, eliminating static polarization and establishing stable voltage response; the method comprises the steps of gradually increasing charging current in a safe current interval of the battery to enable the battery to enter a stable state capable of receiving high-power charging, executing main quick charging in a constant-current or constant-power mode, dynamically restricting the upper limit of charging according to the real-time state of the battery, reducing the charging current to enable the voltage of the battery to be close to a target cut-off voltage steadily, and inhibiting side reactions and lithium precipitation. By constructing a fixed irreversible five-stage charging rhythm of battery awakening-current lifting-fast charging main control-voltage convergence-full charging, a universal and forced logic framework is provided for the charging process, so that the disorder of switching logic is avoided, and the lithium precipitation and deposition risks are greatly reduced.

Inventors

  • CHEN XINLEI

Assignees

  • 陈新磊

Dates

Publication Date
20260508
Application Date
20260403

Claims (10)

  1. 1. The full-domain rhythm fast charging control method of the multi-system power battery is characterized by comprising the following steps of: S1, pre-charging and activating a battery through small current, eliminating static polarization and establishing stable voltage response; S2, gradually increasing charging current in a battery safety current interval to enable the battery to enter a stable state capable of receiving high-power charging; S3, executing main fast charging in a constant-current or constant-power mode, and dynamically restricting the upper limit of charging according to the real-time state of the battery; S4, reducing charging current, enabling the battery voltage to stably approach a target cut-off voltage, and inhibiting side reactions and lithium precipitation; S5, filling with small current, eliminating polarization rebound, realizing accurate full charge, and switching in each stage by taking an inflection point of an electrochemical state of a battery as a switching basis; The charging process sequentially executes five stages S1, S2, S3, S4 and S5 according to a fixed time sequence, and the sequence of each stage is irreversible and can not be omitted.
  2. 2. The method for controlling global rhythm fast charging of a multi-system power battery according to claim 1, wherein in step S1, a small current of 0.1 to 0.3c is adopted for the battery to wake up for 5 to 15 minutes, in step S2, the charging current is gradually increased to 2 to 4c when the current is raised, and in step S3, the charging current in the fast charging main control stage is 4 to 10c.
  3. 3. The method according to claim 1, wherein the charging current is 0.5-1 c during the voltage convergence phase in step S4, and the charging current is 0.05-0.1 c during the full charge of the battery in step S5 for 10-30 minutes.
  4. 4. The method of claim 1, wherein the power cell comprises one or more of lithium iron phosphate, ternary lithium, solid state, semi-solid state, sodium ion, and magnesium ion cells.
  5. 5. The method for controlling global rhythm fast charging of a multi-system power battery according to claim 1, wherein the control method is operated in any one of a battery management system BMS, an on-vehicle controller, a direct current fast charging pile and an energy storage converter, or the multi-devices cooperatively realize global control.
  6. 6. The method for controlling global rhythm fast charging of a multi-system power battery according to claim 5, wherein the multi-device cooperation is that the direct current fast charging pile and the BMS cooperate, and the method specifically comprises the steps that the direct current fast charging pile collects battery voltage, current, temperature and impedance data in real time and identifies electrochemical state inflection points, inflection point signals are transmitted to the BMS, the BMS issues charging current instructions of each stage to the direct current fast charging pile according to the inflection point signals, and the direct current fast charging pile performs current dynamic adjustment to achieve global rhythm fast charging control.
  7. 7. The method of claim 1, wherein the electrochemical state inflection point comprises one or more of a polarization inflection point, an impedance inflection point, and a temperature rise inflection point.
  8. 8. The method of claim 1, wherein the inflection point cross-validation and switch decision mechanism of the multi-system power cell is performed during the phase switch, comprising the steps of: s1, synchronously acquiring and analyzing polarization voltage, impedance and temperature rise data of a battery when judging whether to switch to the next stage or not; S2, based on the acquired data, identifying at least two different types of inflection points of the electrochemical state in parallel or in sequence; and S3, generating an effective stage switching instruction only when the inflection points of the electrochemical states of the at least two different types are identified and confirmed, and triggering the switching from the current stage to the next stage.
  9. 9. The method according to claim 8, wherein the at least two different types of electrochemical state inflection points in step S2 are any two or more of polarization inflection points, impedance inflection points, and temperature rise inflection points.
  10. 10. The method of claim 8, wherein the step S3 of generating the effective phase switching command specifically includes performing a logical AND operation on the identified inflection points of the plurality of electrochemical states or a logical combination operation conforming to a predetermined rule, and outputting the switching command when the operation result is true.

Description

Global rhythm fast charging control method for multi-system power battery Technical Field The invention relates to the technical field of power battery charging control, in particular to a global rhythm fast charging control method of a multi-system power battery. Background With the popularization of electric vehicles and energy storage systems, the rapid charging capability of a power battery becomes a key requirement, however, the diversification of battery chemical systems leads to significant differences in electrochemical characteristics thereof, which presents a serious challenge for developing a universal, efficient and safe rapid charging strategy. The existing fast charging scheme is designed for a single chemical system battery, the universality is poor, the conventional constant-current constant-voltage charging is easy to cause negative electrode lithium precipitation, electrolyte decomposition, polarization accumulation and abnormal temperature rise under high multiplying power, the cycle life and the use safety of the battery are seriously influenced, the partial fast charging technology depends on a special hardware structure or a specific battery cell formula, the adaptive scene is limited, the transformation cost is high, the segmentation charging scheme does not establish a strictly irreversible stage time sequence and electrochemical inflection point switching mechanism, the stage switching randomness is strong, and the balance between the safety and the long cycle life is difficult to realize under the 4C-10C ultra-fast charging multiplying power. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a full-domain rhythm fast charging control method of a multi-system power battery, which at least solves the problems in the prior art. The invention aims to realize the technical scheme that the full-domain rhythm fast charge control method of the multi-system power battery comprises the following steps of: S1, pre-charging and activating a battery through small current, eliminating static polarization and establishing stable voltage response; S2, gradually increasing charging current in a battery safety current interval to enable the battery to enter a stable state capable of receiving high-power charging; S3, executing main fast charging in a constant-current or constant-power mode, and dynamically restricting the upper limit of charging according to the real-time state of the battery; S4, reducing charging current, enabling the battery voltage to stably approach a target cut-off voltage, and inhibiting side reactions and lithium precipitation; S5, filling with small current, eliminating polarization rebound, realizing accurate full charge, and switching in each stage by taking an inflection point of an electrochemical state of a battery as a switching basis; The charging process sequentially executes five stages S1, S2, S3, S4 and S5 according to a fixed time sequence, and the sequence of each stage is irreversible and can not be omitted. Preferably, in the step S1, a small current of 0.1-0.3C is adopted when the battery is awakened, the duration is 5-15 minutes, in the step S2, the charging current is gradually increased to 2-4C when the current is lifted, and in the step S3, the charging current in the quick charging main control stage is 4-10C. Preferably, the charging current is 0.5C-1C in the voltage convergence stage in the step S4, and 0.05C-0.1C is adopted in the step S5 when the battery is fully charged, and the charging current lasts for 10-30 minutes. Preferably, the power battery comprises one or more of lithium iron phosphate, ternary lithium, solid state, semi-solid state, sodium ion, and magnesium ion batteries. Preferably, the control method is operated in any one device of a battery management system BMS, a vehicle-mounted controller, a direct-current fast charging pile and an energy storage converter, or multiple devices cooperatively realize global control. Preferably, the multi-equipment cooperation is that the direct-current quick-charging pile and the BMS cooperate specifically comprises the steps that the direct-current quick-charging pile collects battery voltage, current, temperature and impedance data in real time and identifies an electrochemical state inflection point, an inflection point signal is transmitted to the BMS, the BMS issues charging current instructions of each stage to the direct-current quick-charging pile according to the inflection point signal, and the direct-current quick-charging pile executes current dynamic adjustment to realize the full-domain rhythm quick-charging control. Preferably, the electrochemical state inflection point comprises one or more of a polarization inflection point, an impedance inflection point and a temperature rise inflection point. Preferably, when stage switching is performed, a inflection point cross-validation and switching decision mechanism of multivariate fusion is performed,