CN111641001A - Correction method, device, storage medium and device of battery system - Google Patents

Correction method, device, storage medium and device of battery system Download PDF

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Publication number
CN111641001A
CN111641001A CN202010515505.7A CN202010515505A CN111641001A CN 111641001 A CN111641001 A CN 111641001A CN 202010515505 A CN202010515505 A CN 202010515505A CN 111641001 A CN111641001 A CN 111641001A
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soc
value
battery
correction
charging
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CN111641001B (en
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叶昌森
梁荣荣
燕逸飞
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Anhui Jianghuai Automobile Group Corp
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Anhui Jianghuai Automobile Group Corp
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/44—Methods for charging or discharging
    • H01M10/443—Methods for charging or discharging in response to temperature
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Abstract

The invention relates to the technical field of battery system correction, and discloses a correction method, equipment, a storage medium and a device of a battery system. The method comprises the steps of obtaining a charging correction flag bit in the charging process and a corresponding pre-stored battery state of charge (SOC) correction difference value; acquiring an SOC value of a battery to be corrected, and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value; when the SOC value of the battery to be corrected reaches a preset charging threshold value, acquiring a charging SOC value maintaining the SOC value of the battery to be corrected in a state of the preset charging threshold value; and offsetting the pre-stored SOC correction difference value according to the charging SOC value to realize the correction of the battery system, so that the SOC value correction is not required to be carried out in a cliff type mode when the corrected SOC value is obtained through an SOC correction curve, and the SOC value is offset through the charging SOC value in the next charging so as to realize the slow correction of the SOC.

Description

Correction method, device, storage medium and device of battery system
Technical Field
The present invention relates to the field of battery system correction technologies, and in particular, to a method, an apparatus, a storage medium, and a device for correcting a battery system.
Background
At present, SOC (State of Charge), namely SOC estimation strategies mainly comprise an open-circuit voltage method, an ampere-hour integration method, an artificial neural network method, a Kalman filtering method and the like. In-industry battery SOC estimation mainly uses an Open Circuit Voltage (OCV) correction algorithm assisted by ampere-hour integration, but SOC estimation error can be controlled to be +/-4% based on battery pack consistency within a normal range.
Because the battery SOC-OCV correction in the industry is generally that after the current OCV is obtained according to parameter table lookup, the current SOC value is directly or indirectly corrected, namely the SOC is accelerated to drop in the discharging process, the cliff-type jump of the SOC is caused by direct correction, a customer cannot accept the cliff-type jump in the using process, and the user experience is not facilitated.
Disclosure of Invention
The invention mainly aims to provide a correction method, equipment, a storage medium and a device of a battery system, aiming at more comprehensively realizing slow correction of SOC.
In order to achieve the above object, the present invention provides a method for correcting a battery system, including the steps of:
acquiring a charging correction flag bit and a corresponding pre-stored battery state of charge (SOC) correction difference in the charging process;
acquiring an SOC value of a battery to be corrected, and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value;
when the SOC value of the battery to be corrected reaches a preset charging threshold value, acquiring a charging SOC value maintaining the SOC value of the battery to be corrected in a state of the preset charging threshold value;
and offsetting a pre-stored SOC correction difference value according to the charging SOC value so as to realize the correction of the battery system.
Optionally, before the obtaining of the charging correction flag bit and the corresponding pre-stored battery state of charge SOC correction difference in the charging process, the method further includes:
when the battery system reaches a correction state, acquiring voltage parameter information and temperature parameter information of the battery;
inquiring an SOC correction curve according to the voltage parameter information and the temperature parameter information to obtain a target SOC value;
acquiring an original SOC value;
judging whether the difference value of the original SOC value and the target SOC value is larger than a first SOC threshold value or not;
when the difference value between the original SOC value and the target SOC value is larger than a first SOC threshold value, the difference value between the original SOC value and the target SOC value is stored in a preset area to serve as a pre-stored SOC correction difference value, and a charging correction flag bit is set according to the pre-stored SOC correction difference value.
Optionally, before determining whether a difference between the original SOC value and the target SOC value is greater than a first SOC threshold, the method further includes:
judging whether the target SOC value is smaller than a second SOC threshold value;
and when the target SOC value is smaller than a second SOC threshold value, executing the step of judging whether the difference value between the original SOC value and the target SOC value is larger than a first SOC threshold value.
Optionally, after the pre-stored SOC correction difference is cancelled according to the SOC value, the method further includes:
acquiring a pre-stored SOC correction difference value after offset;
judging whether the pre-stored SOC correction difference value after offset reaches a third SOC threshold value;
when the pre-stored SOC correction difference value after the offsetting does not reach a third SOC threshold value, judging whether the SOC value of the battery to be corrected reaches a full charge threshold value;
when the SOC value of the battery to be corrected does not reach a full charge threshold value, judging whether a battery charge stopping instruction is received or not;
and when a battery charging stopping instruction is received, updating the pre-stored SOC correction difference value in the preset area through the pre-stored SOC correction difference value after the pre-stored SOC correction difference value is offset.
Optionally, before the obtaining of the charging correction flag bit and the corresponding pre-stored battery state of charge SOC correction difference in the charging process, the method further includes:
judging whether a charging correction flag bit exists;
and when the charging correction flag bit is stored, executing the step of acquiring the charging correction flag bit in the charging process and the corresponding pre-stored battery state of charge SOC correction difference value.
Optionally, the obtaining the SOC value of the battery to be corrected and determining whether the SOC value of the battery to be corrected reaches a preset charging threshold include:
acquiring an SOC value of a battery to be modified, and judging whether the SOC value of the battery to be modified reaches a full charge threshold value;
and when the SOC value of the battery to be corrected does not reach the full charge threshold, judging whether the SOC value of the battery to be corrected reaches a preset charge threshold.
Optionally, after the acquiring the SOC value of the battery to be corrected and determining whether the SOC value of the battery to be corrected reaches the preset charging threshold, the method further includes:
when the SOC value of the battery to be corrected does not reach a preset charging threshold value, judging whether a battery charging stopping instruction is obtained or not;
and when the battery charging stopping instruction is not acquired, returning to the step of acquiring the SOC value of the battery to be corrected and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value.
Further, to achieve the above object, the present invention also proposes a correction apparatus of a battery system, including: the battery system correction method comprises a memory, a processor and a correction program stored on the memory and running on the processor, wherein the correction program of the battery system realizes the steps of the battery system correction method when being executed by the processor.
In addition, in order to achieve the above object, the present invention further provides a storage medium having a battery system modification program stored thereon, wherein the battery system modification program, when executed by a processor, implements the steps of the battery system modification method as described above.
In order to achieve the above object, the present invention also provides a correction device for a battery system, including:
the acquisition module is used for acquiring a charging correction flag bit and a corresponding pre-stored battery SOC correction difference value in the charging process;
the judging module is used for acquiring the SOC value of the battery to be corrected and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value;
the acquisition module is further configured to acquire a charging SOC value that maintains the SOC value of the battery to be corrected at a preset charging threshold value state when the SOC value of the battery to be corrected reaches the preset charging threshold value;
and the correction module is used for offsetting the pre-stored SOC correction difference value according to the charging SOC value so as to realize the correction of the battery system.
According to the technical scheme provided by the invention, a charging correction flag bit and a corresponding pre-stored battery state of charge (SOC) correction difference value in a charging process are obtained; acquiring an SOC value of a battery to be corrected, and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value; when the SOC value of the battery to be corrected reaches a preset charging threshold value, acquiring a charging SOC value maintaining the SOC value of the battery to be corrected in a state of the preset charging threshold value; and offsetting the pre-stored SOC correction difference value according to the charging SOC value to realize the correction of the battery system, so that the SOC value correction is not required to be carried out in a cliff type mode when the corrected SOC value is obtained through an SOC correction curve, and the SOC value is offset through the charging SOC value in the next charging so as to realize the slow correction of the SOC.
Drawings
Fig. 1 is a schematic structural diagram of a correction device of a battery system of a hardware operating environment according to an embodiment of the present invention;
fig. 2 is a schematic flow chart illustrating a modification method of a battery system according to a first embodiment of the present invention;
FIG. 3 is a schematic flow chart illustrating a modification method of a battery system according to a second embodiment of the present invention;
fig. 4 is a schematic overall flowchart illustrating a setting of a charging correction flag according to an embodiment of a correction method for a battery system of the present invention;
FIG. 5 is a schematic diagram of a SOC correction curve according to an embodiment of the correction method of the battery system of the present invention;
fig. 6 shows an OCV correction correspondence relationship according to an embodiment of the correction method for a battery system of the present invention;
fig. 7 is a schematic flow chart illustrating a modification method of a battery system according to a third embodiment of the present invention;
fig. 8 is a schematic overall flowchart illustrating a SOC correction difference value correction according to an embodiment of the correction method for a battery system of the present invention;
fig. 9 is a block diagram showing a configuration of a correction device of a battery system according to a first embodiment of the present invention.
The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.
Detailed Description
It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The main solution of the embodiment of the invention is as follows: acquiring a charging correction flag bit and a corresponding pre-stored battery state of charge (SOC) correction difference in the charging process; acquiring an SOC value of a battery to be corrected, and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value; when the SOC value of the battery to be corrected reaches a preset charging threshold value, acquiring a charging SOC value maintaining the SOC value of the battery to be corrected in a state of the preset charging threshold value; and offsetting the pre-stored SOC correction difference value according to the charging SOC value to realize the correction of the battery system, so that the SOC value correction is not required to be carried out in a cliff type mode when the corrected SOC value is obtained through an SOC correction curve, and the SOC value is offset through the charging SOC value in the next charging so as to realize the slow correction of the SOC.
The main technical terms related to the embodiments of the present application include:
SOC: state of charge, which is the State of charge, is used to reflect the remaining capacity of the battery, and is numerically defined as the ratio of the remaining capacity to the battery capacity, expressed as a percentage. The value range of the battery charging indicator is 0-1, when the SOC is 0, the battery is completely discharged, and when the SOC is 1, the battery is completely charged. The SOC of the battery cannot be directly measured, and can only be estimated by parameters such as terminal voltage, charge and discharge current, internal resistance and the like of the battery, and the parameters are influenced by various uncertain factors such as battery aging, environmental temperature change, automobile driving state and the like.
OCV: open circuit voltage refers to the potential difference between the two poles when the battery is not discharged and Open-circuited.
VCU: the Vehicle controller is used as a central control unit of the new energy Vehicle and is the core of the whole control system. The VCU collects the states of a motor and a battery, collects signals of an accelerator pedal, a brake pedal, an actuator and a sensor, and monitors the action of each part controller at the lower layer after making corresponding judgment according to comprehensive analysis of the intention of a driver, and the VCU is responsible for normal running, brake energy feedback, energy management of an engine and a power battery of the whole automobile, network management, fault diagnosis and processing, vehicle state monitoring and the like of the automobile, so that the whole automobile can work normally and stably under the states of better dynamic property, higher economy and reliability.
LBC: the local master controller on the automobile can analyze the fault reason through the detection circuit in the maintenance process.
SOH: state Of Health, battery Health, is expressed as the capacity, Health and performance status Of the battery, i.e., the percentage Of the full charge capacity Of the battery relative to the rated capacity, with 100% Of the battery that is newly shipped and 0% Of the battery that is completely scrapped.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a correction device of a battery system in a hardware operating environment according to an embodiment of the present invention.
As shown in fig. 1, the correction device of the battery system may include: a processor 1001, such as a Central Processing Unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Wherein a communication bus 1002 is used to enable connective communication between these components. The user interface 1003 may include a Display screen (Display), the optional user interface 1003 may also include a standard wired interface and a wireless interface, and the wired interface of the user interface 1003 may be a Universal Serial Bus (USB) interface in the present invention. The network interface 1004 may optionally include a standard wired interface as well as a wireless interface (e.g., WI-FI interface). The Memory 1005 may be a high speed Random Access Memory (RAM); or a stable Memory, such as a Non-volatile Memory (Non-volatile Memory), and may be a disk Memory. The memory 1005 may alternatively be a storage device separate from the processor 1001.
It will be appreciated by those skilled in the art that the configuration shown in fig. 1 does not constitute a limitation of the modified arrangement of the battery system and may include more or fewer components than those shown, or some components in combination, or a different arrangement of components.
As shown in fig. 1, a memory 1005, which is a kind of computer storage medium, may include therein an operating system, a network communication module, a user interface module, and a modification program of a battery system.
In the modification device of the battery system shown in fig. 1, the network interface 1004 is mainly used for connecting a background server and performing data communication with the background server; the user interface 1003 is mainly used for connecting peripheral equipment; the correction apparatus of the battery system calls the correction program of the battery system stored in the memory 1005 through the processor 1001 and executes the correction method of the battery system provided by the embodiment of the present invention.
Based on the above hardware structure, an embodiment of the correction method of the battery system of the present invention is provided.
Referring to fig. 2, fig. 2 is a schematic flow chart of a modification method of a battery system according to a first embodiment of the present invention.
In a first embodiment, the correction method of the battery system includes the steps of:
step S10: and acquiring a charging correction flag bit and a corresponding pre-stored battery state of charge (SOC) correction difference in the charging process.
It should be noted that the main execution unit of the present embodiment is a correction device of the battery system, and may also be other devices that can achieve the same or similar functions.
In this embodiment, the charging process is a slow charging process, and since the SOC can be effectively adjusted in the slow charging process, the charging correction flag is an SOC value to be corrected obtained before the current charging and when the SOC correction state is satisfied, the SOC value to be corrected is obtained when the SOC correction is performed, and is expressed as Δ SOC correction difference, the SOC correction difference is expressed, and when the SOC correction is obtained, the SOC correction difference is not directly corrected, but a charging correction flag is set, and the SOC correction is performed through the charging process in the next charging, so as to avoid direct cliff type correction, improve user experience, where the charging correction flag may be 0 or 1, express the correction flag, and may be marked by other means.
Step S20: and acquiring the SOC value of the battery to be corrected, and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value.
It can be understood that the SOC value of the battery to be corrected is a currently displayed SOC value, for example, the current SOC value displayed on the battery display interface is 25%, the preset charging threshold is 99%, and other parameter information may also be provided.
Step S30: and when the SOC value of the battery to be corrected reaches a preset charging threshold value, acquiring the charging SOC value maintaining the SOC value of the battery to be corrected in a state of the preset charging threshold value.
In this embodiment, when the SOC value of the battery to be modified reaches the preset charging threshold, a charging SOC value for maintaining the SOC value of the battery to be modified at the preset charging threshold is obtained, for example, the charging capacity during SOC maintenance of 99% is calculated, assuming that the charging capacity is 10Ah and the total capacity of the battery system is 100Ah, the charging SOC is 10%, that is, 10Ah/100Ah is 10%, that is, according to the obtained charging capacity information and the total capacity information of the battery system, the charging SOC value is obtained according to the charging capacity information and the total capacity information of the battery system, and is represented by SOC Δ charging.
Step S40: and offsetting a pre-stored SOC correction difference value according to the charging SOC value so as to realize the correction of the battery system.
In a specific implementation, when Δ SOC is 15%, that is, Δ SOC remaining- Δ SOC charge- Δ SOC 15% -10% -5%, if the full charge flag is reached at this time, Δ SOC remaining- Δ 5% is cleared, and if the full charge flag is not reached at this time and the battery is powered down, Δ SOC 5% is stored, thereby implementing the correction of the battery system.
According to the scheme, the charging correction flag bit in the charging process and the corresponding pre-stored battery state of charge (SOC) correction difference value are obtained; acquiring an SOC value of a battery to be corrected, and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value; when the SOC value of the battery to be corrected reaches a preset charging threshold value, acquiring a charging SOC value maintaining the SOC value of the battery to be corrected in a state of the preset charging threshold value; and offsetting the pre-stored SOC correction difference value according to the charging SOC value to realize the correction of the battery system, so that the SOC value correction is not required to be carried out in a cliff type mode when the corrected SOC value is obtained through an SOC correction curve, and the SOC value is offset through the charging SOC value in the next charging so as to realize the slow correction of the SOC.
Referring to fig. 3, fig. 3 is a schematic flow chart of a second embodiment of the method for correcting the battery system according to the present invention, and the second embodiment of the method for correcting the battery system according to the present invention is proposed based on the first embodiment shown in fig. 2.
In the second embodiment, the feature information of the vehicle-mounted terminal includes identification code information of the vehicle-mounted terminal, and before the step S10, the method further includes:
and step S101, when the battery system reaches a correction state, acquiring voltage parameter information and temperature parameter information of the battery.
In this embodiment, in the OCV correction, that is, the open-circuit voltage correction method, after the battery resting time of the VCU is longer than 1 hour, determining whether the battery state meets the OCV correction condition, if so, setting the OCV correction flag bit, and correcting the SOC in the next charging or middle of the vehicle, as shown in the overall flow diagram of setting the charging correction flag bit shown in fig. 4, activating the VCU and activating the LBC, determining whether the vehicle resting time is longer than 1 hour, and if so, obtaining the battery current, determining whether the battery current is smaller than 2A, and when the battery current is smaller than 2A, obtaining Vmin and Tmin reported by the LBC, that is, the voltage parameter information and the temperature parameter information in this embodiment may also include other parameter information, which is not limited in this embodiment, thereby implementing the identification of the battery correction state, and ensuring that the vehicle obtains the SOC correction value in the stable state, the accuracy of the SOC correction value is ensured.
And S102, inquiring an SOC correction curve according to the voltage parameter information and the temperature parameter information to obtain a target SOC value.
Continuing as shown in fig. 4, determining whether Tmin is greater than 0 ℃, when Tmin is greater than 0 ℃, querying the SOC correction curve according to Vmin and Tmin to obtain a target SOC value, as shown in the SOC correction curve diagram of fig. 5, obtaining a corresponding SOC value, i.e. the target SOC value in this embodiment, by using the SOC correction curve, determining whether the target SOC value is less than the adjustment threshold when the target SOC value is obtained, and executing step S103 when the target SOC value is less than the adjustment threshold.
In this embodiment, in order to obtain the SOC correction curve, the SOC-OCV data test calibration is performed, the battery cells with SOH of 100%, 90%, 80% are left to stand in an environment chamber at 25 ℃, when the temperature T is within the range of 25 ± 2 ℃, 0.5C is charged to 3.45V, 10A is charged to 3.65V, 1C is discharged to 2.3V, 1C is used to discharge at intervals of 10% to adjust SOC, and the SOC is left to stand for 1h, and an OCV value is recorded. Recording the SOC value corresponding to the cell voltage V, as shown in the OCV corrected correspondence of fig. 6 below, SOH 100% cells, SOH 90%, 80% cells, from the cycle life cycle to capacity fade to 90% and 80% of the initial capacity, as charged by 1C or 1C discharge, SOH 90% representing cell current capacity fade to 90% of the initial capacity, where 1C represents large capacity processing and 10A represents small capacity processing.
Step S103, acquiring an original SOC value.
Note that the original SOC value is an SOC value obtained in a previous state in the state of charge and not yet corrected, that is, an SOC value displayed in the previous state.
And step S104, judging whether the difference value between the original SOC value and the target SOC value is larger than a first SOC threshold value.
In this embodiment, the first SOC threshold is 4%, and may also be other parameter information, which is not limited in this embodiment, taking 4% as an example, the difference between the original SOC value and the target SOC value is obtained, so as to implement effective correction of the SOC value, and since the difference between the original SOC value and the target SOC value is small, the SOC value is corrected within an allowable error range, in this case, correction is not needed, and when the difference between the original SOC value and the target SOC value is large, the SOC value is corrected, so as to improve the validity of SOC value correction.
Further, before the step S104, the method further includes:
judging whether the target SOC value is smaller than a second SOC threshold value; step S104 is performed when the target SOC value is less than a second SOC threshold value.
It can be understood that, the second SOC threshold is 15%, and other parameter information may be provided, which is not limited in this embodiment, 15% is taken as an example for description, and when the target SOC value is obtained, it is necessary to determine the target SOC value, and determine whether the target SOC value is valid, so as to improve the efficiency of correction.
And S105, when the difference value between the original SOC value and the target SOC value is larger than a first SOC threshold value, storing the difference value between the original SOC value and the target SOC value into a preset area to serve as a pre-stored SOC correction difference value, and setting a charging correction flag bit according to the pre-stored SOC correction difference value.
In the present embodiment, only the OCV correction flag is set and the SOC correction is not performed, and since the OCV correction is performed directly here, the cliff-type SOC drop may occur and the user cannot accept it, and only the corrected Δ SOC value is confirmed by setting only the OCV correction flag and not performing the OC correction, and the generated Δ SOC is erased in the next charging process.
According to the scheme, when the battery system reaches the correction state, the voltage parameter information and the temperature parameter information of the battery are acquired; inquiring an SOC correction curve according to the voltage parameter information and the temperature parameter information to obtain a target SOC value; acquiring an original SOC value; judging whether the difference value of the original SOC value and the target SOC value is larger than a first SOC threshold value or not; when the difference value between the original SOC value and the target SOC value is larger than a first SOC threshold value, the difference value between the original SOC value and the target SOC value is stored in a preset area to serve as a pre-stored SOC correction difference value, a charging correction flag bit is set according to the pre-stored SOC correction difference value, only an OCV correction flag bit is set, SOC correction is not carried out, and therefore the cliff-type jump of the SOC is avoided.
Referring to fig. 7, fig. 7 is a schematic flow chart of a third embodiment of the method for correcting a battery system according to the present invention, and the third embodiment of the method for correcting a battery system according to the present invention is proposed based on the first embodiment or the second embodiment.
In the third embodiment, after the step S40, the method further includes:
step S401, obtaining the pre-stored SOC correction difference after offset.
As shown in the overall flow chart of the SOC correction difference correction shown in fig. 8, during the slow charging process, for example, the SOC shows 99%, at this time, the SOC value is only 99% -15% to 84%, the charged capacity during the SOC maintenance of 99% is calculated, assuming that the charged capacity is 10Ah and the total capacity of the battery system is 100Ah, the charged SOC is 10%, 10Ah/100Ah is 10%, that is, △ SOC remains △ SOC to △ SOCCharging device15% -10% -5%, if the full charge flag is reached, △ SOC is clearedSurplus5%, if the full charge flag is not reached and power is down, △ SOC is stored 5%, △ SOCSurplusThe difference is corrected for the pre-stored SOC after the cancellation.
Step S402, judging whether the pre-stored SOC correction difference value after offset reaches a third SOC threshold value.
In this embodiment, when the pre-stored SOC correction difference after the cancellation reaches a third SOC threshold value, which is 0%, at △ SOCSurplusWhen 0% is reached, this indicates that the correction is complete, in which case it will be presetArea saved △ SOCSurplusAnd clearing is carried out, so that the SOC correction difference value is updated in real time.
Step S403, when the pre-stored SOC correction difference value after the cancellation does not reach the third SOC threshold value, determining whether the SOC value of the battery to be corrected reaches the full charge threshold value.
In a specific implementation, the full charge threshold is to obtain a full charge flag bit, and may also be to monitor that the SOC value is 100%, which is not limited in this embodiment.
In this embodiment, there are two ways, one way is when the pre-stored SOC correction difference value after cancellation does not reach the third SOC threshold value, for example, when the pre-stored SOC correction difference value after cancellation is 2%, in this case, the pre-stored SOC correction difference value in the storage area is updated according to the pre-stored SOC correction difference value after cancellation, and the other way is when the pre-stored SOC correction difference value after cancellation does not reach the third SOC threshold value, for example, when the pre-stored SOC correction difference value after cancellation is-2%, in this case, it indicates △ SOCCharging deviceIf the SOC is greater than △, the pre-stored SOC correction difference in the storage area does not need to be updated, but the full charge flag is set to indicate that the SOC is full, that is, △ SOC is cleared, and the full charge threshold is determined to determine whether the △ SOC is cancelled out.
And step S404, judging whether a battery charging stopping instruction is received or not when the SOC value of the battery to be corrected does not reach a full charging threshold value.
In this embodiment, the battery charging suspension command may be a VCU power-off command, or may also be other battery charging suspension manners, which is not limited in this embodiment, the VCU power-off command is taken as an example, and when the battery SOC value to be corrected reaches the full charge threshold, △ SOC stored in the storage area is clearedSurplus。
Step S405, when the battery charge suspension instruction is received, updating the pre-stored SOC correction difference in the preset region by the pre-stored SOC correction difference after the cancellation.
It will be appreciated that the pre-stored SOC correction difference after cancellation is △ SOCSurplusDisclosure of the invention△ SOCSurplusUpdating the pre-stored SOC correction difference △ SOC, for example, △ SOC when the pre-stored SOC in the preset region is 15% at △ SOCCharging deviceAt 10%, △ SOC was obtainedSurplus5%, in this case, the pre-stored SOC at △ in the preset region is no longer 15%, but is △ SOCSurplusThe SOC correction difference value is 5 percent, namely the real-time update of the pre-stored SOC correction difference value is realized, and the accuracy of SOC correction is ensured.
Further, before the step S10, the method further includes:
judging whether a charging correction flag bit exists; if the charge correction flag is stored, step S10 is executed.
In this embodiment, the charging correction flag may be 0 or 1, which indicates a correction flag, and may also be marked by other manners, which is not limited in this embodiment, for example, 1 indicates that the charging correction flag is set, and 0 indicates that the charging correction flag is not set.
In a specific implementation, as shown in fig. 8, if the charging correction flag bit is stored, the SOC may pass through △Charging deviceThe SOC is offset, and when the charging correction flag bit is not stored, the SOC can be directly △SurplusAnd offsetting is carried out, so that initial judgment of SOC correction is realized, and the SOC correction efficiency is improved.
Further, the step S20 includes:
acquiring an SOC value of a battery to be modified, and judging whether the SOC value of the battery to be modified reaches a full charge threshold value; and when the SOC value of the battery to be corrected does not reach the full charge threshold, judging whether the SOC value of the battery to be corrected reaches a preset charge threshold.
As shown in fig. 8, when the SOC value of the battery to be modified does not reach the full charge threshold, it is determined whether the SOC value of the battery to be modified reaches the SOC of 99%, and when the SOC value of the battery to be modified reaches the SOC of 99%, it is determined whether a battery charge stop instruction is obtained, so as to improve the accuracy of SOC modification.
Further, after the step S20, the method further includes:
when the SOC value of the battery to be corrected does not reach a preset charging threshold value, judging whether a battery charging stopping instruction is obtained or not; when the battery charge suspension instruction is not acquired, the process returns to step S20.
In a specific implementation, when the SOC value of the battery to be corrected does not reach 99 percent, judging whether a battery charging stopping instruction is acquired, if the battery charging stopping instruction is not acquired, returning to the step S20, and if the battery charging stopping instruction is not acquired, determining △ SOCSurplusAnd keeping the storage unchanged and continuing to store.
According to the scheme, before SOC correction is carried out, whether the charging correction flag bit exists or not is judged, whether the full charging threshold is reached or not is judged or not, and preliminary screening is carried out according to the judgment result, so that the accuracy of SOC correction is improved.
Furthermore, an embodiment of the present invention further provides a storage medium, where a modification program of a battery system is stored, and the modification program of the battery system is executed by a processor to implement the steps of the modification method of the battery system as described above.
Since the storage medium adopts all technical solutions of all the embodiments, at least all the beneficial effects brought by the technical solutions of the embodiments are achieved, and no further description is given here.
In addition, referring to fig. 9, an embodiment of the present invention further provides a correction device for a battery system, where the correction device for a battery system includes:
the obtaining module 10 is configured to obtain a charging correction flag bit during a charging process and a corresponding pre-stored battery state of charge SOC correction difference.
In this embodiment, the charging process is a slow charging process, and since the SOC can be effectively adjusted in the slow charging process, the charging correction flag is an SOC value to be corrected obtained before the current charging and when the SOC correction state is satisfied, the SOC value to be corrected is obtained when the SOC correction is performed, and is expressed as Δ SOC correction difference, the SOC correction difference is expressed, and when the SOC correction is obtained, the SOC correction difference is not directly corrected, but a charging correction flag is set, and the SOC correction is performed through the charging process in the next charging, so as to avoid direct cliff type correction, improve user experience, where the charging correction flag may be 0 or 1, express the correction flag, and may be marked by other means.
The determining module 20 is configured to obtain an SOC value of the battery to be modified, and determine whether the SOC value of the battery to be modified reaches a preset charging threshold.
It can be understood that the SOC value of the battery to be corrected is a currently displayed SOC value, for example, the current SOC value displayed on the battery display interface is 25%, the preset charging threshold is 99%, and other parameter information may also be provided.
The obtaining module 10 is further configured to obtain a charging SOC value maintaining the SOC value of the battery to be corrected in a state of a preset charging threshold when the SOC value of the battery to be corrected reaches the preset charging threshold.
In this embodiment, when the SOC value of the battery to be modified reaches the preset charging threshold, a charging SOC value for maintaining the SOC value of the battery to be modified at the preset charging threshold is obtained, for example, the charging capacity during SOC maintenance of 99% is calculated, assuming that the charging capacity is 10Ah and the total capacity of the battery system is 100Ah, the charging SOC is 10%, that is, 10Ah/100Ah is 10%, that is, according to the obtained charging capacity information and the total capacity information of the battery system, the charging SOC value is obtained according to the charging capacity information and the total capacity information of the battery system, and is represented by SOC Δ charging.
And the correction module 30 is configured to offset a pre-stored SOC correction difference according to the charging SOC value, so as to correct the battery system.
In a specific implementation, when Δ SOC is 15%, that is, Δ SOC remaining- Δ SOC charge- Δ SOC 15% -10% -5%, if the full charge flag is reached at this time, Δ SOC remaining- Δ 5% is cleared, and if the full charge flag is not reached at this time and the battery is powered down, Δ SOC 5% is stored, thereby implementing the correction of the battery system.
According to the scheme, the charging correction flag bit in the charging process and the corresponding pre-stored battery state of charge (SOC) correction difference value are obtained; acquiring an SOC value of a battery to be corrected, and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value; when the SOC value of the battery to be corrected reaches a preset charging threshold value, acquiring a charging SOC value maintaining the SOC value of the battery to be corrected in a state of the preset charging threshold value; and offsetting the pre-stored SOC correction difference value according to the charging SOC value to realize the correction of the battery system, so that the SOC value correction is not required to be carried out in a cliff type mode when the corrected SOC value is obtained through an SOC correction curve, and the SOC value is offset through the charging SOC value in the next charging so as to realize the slow correction of the SOC.
In an embodiment, the correction device of the battery system further includes a charging correction flag setting module;
the charging correction flag bit setting module is used for acquiring voltage parameter information and temperature parameter information of the battery when the battery system reaches a correction state;
inquiring an SOC correction curve according to the voltage parameter information and the temperature parameter information to obtain a target SOC value;
acquiring an original SOC value;
judging whether the difference value of the original SOC value and the target SOC value is larger than a first SOC threshold value or not;
when the difference value between the original SOC value and the target SOC value is larger than a first SOC threshold value, the difference value between the original SOC value and the target SOC value is stored in a preset area to serve as a pre-stored SOC correction difference value, and a charging correction flag bit is set according to the pre-stored SOC correction difference value.
In an embodiment, the charging correction flag setting module is further configured to determine whether the target SOC value is smaller than a second SOC threshold.
In one embodiment, the correction device of the battery system further comprises an update module;
the updating module is also used for acquiring a pre-stored SOC correction difference value after offset;
judging whether the pre-stored SOC correction difference value after offset reaches a third SOC threshold value;
when the pre-stored SOC correction difference value after the offsetting does not reach a third SOC threshold value, judging whether the SOC value of the battery to be corrected reaches a full charge threshold value;
when the SOC value of the battery to be corrected does not reach a full charge threshold value, judging whether a battery charge stopping instruction is received or not;
and when a battery charging stopping instruction is received, updating the pre-stored SOC correction difference value in the preset area through the pre-stored SOC correction difference value after the pre-stored SOC correction difference value is offset.
In an embodiment, the determining module 20 is further configured to determine whether there is a charging correction flag.
In an embodiment, the determining module 20 is further configured to obtain a to-be-modified battery SOC value, and determine whether the to-be-modified battery SOC value reaches a full charge threshold;
and when the SOC value of the battery to be corrected does not reach the full charge threshold, judging whether the SOC value of the battery to be corrected reaches a preset charge threshold.
In an embodiment, the determining module 20 is further configured to determine whether a battery charging suspension instruction is obtained when the SOC value of the battery to be corrected does not reach a preset charging threshold.
The correction device of the battery system of the present invention adopts all the technical solutions of all the above embodiments, so that at least all the beneficial effects brought by the technical solutions of the above embodiments are achieved, and details are not repeated herein.
The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims (10)

1. A method for correcting a battery system, comprising:
acquiring a charging correction flag bit and a corresponding pre-stored battery state of charge (SOC) correction difference in the charging process;
acquiring an SOC value of a battery to be corrected, and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value;
when the SOC value of the battery to be corrected reaches a preset charging threshold value, acquiring a charging SOC value maintaining the SOC value of the battery to be corrected in a state of the preset charging threshold value;
and offsetting a pre-stored SOC correction difference value according to the charging SOC value so as to realize the correction of the battery system.
2. The method for correcting a battery system according to claim 1, wherein before the obtaining the charging correction flag bit and the corresponding pre-stored battery SOC correction difference during the charging process, the method further comprises:
when the battery system reaches a correction state, acquiring voltage parameter information and temperature parameter information of the battery;
inquiring an SOC correction curve according to the voltage parameter information and the temperature parameter information to obtain a target SOC value;
acquiring an original SOC value;
judging whether the difference value of the original SOC value and the target SOC value is larger than a first SOC threshold value or not;
when the difference value between the original SOC value and the target SOC value is larger than a first SOC threshold value, the difference value between the original SOC value and the target SOC value is stored in a preset area to serve as a pre-stored SOC correction difference value, and a charging correction flag bit is set according to the pre-stored SOC correction difference value.
3. The method for correcting a battery system according to claim 2, wherein before determining whether the difference between the original SOC value and the target SOC value is greater than a first SOC threshold value, the method further comprises:
judging whether the target SOC value is smaller than a second SOC threshold value;
and when the target SOC value is smaller than a second SOC threshold value, executing the step of judging whether the difference value between the original SOC value and the target SOC value is larger than a first SOC threshold value.
4. The correction method of a battery system according to any one of claims 1 to 3, wherein after the canceling of the pre-stored SOC correction difference value according to the charging SOC value, the method further comprises:
acquiring a pre-stored SOC correction difference value after offset;
judging whether the pre-stored SOC correction difference value after offset reaches a third SOC threshold value;
when the pre-stored SOC correction difference value after the offsetting does not reach a third SOC threshold value, judging whether the SOC value of the battery to be corrected reaches a full charge threshold value;
when the SOC value of the battery to be corrected does not reach a full charge threshold value, judging whether a battery charge stopping instruction is received or not;
and when a battery charging stopping instruction is received, updating the pre-stored SOC correction difference value in the preset area through the pre-stored SOC correction difference value after the pre-stored SOC correction difference value is offset.
5. The method for correcting the battery system according to any one of claims 1 to 3, wherein before the acquiring the charging correction flag bit and the corresponding pre-stored battery state of charge (SOC) correction difference during the charging process, the method further comprises:
judging whether a charging correction flag bit exists;
and when the charging correction flag bit is stored, executing the step of acquiring the charging correction flag bit in the charging process and the corresponding pre-stored battery state of charge SOC correction difference value.
6. The method for correcting the battery system according to any one of claims 1 to 3, wherein the obtaining the SOC value of the battery to be corrected and the determining whether the SOC value of the battery to be corrected reaches a preset charging threshold value comprise:
acquiring an SOC value of a battery to be modified, and judging whether the SOC value of the battery to be modified reaches a full charge threshold value;
and when the SOC value of the battery to be corrected does not reach the full charge threshold, judging whether the SOC value of the battery to be corrected reaches a preset charge threshold.
7. The method for correcting the battery system according to any one of claims 1 to 3, wherein after the obtaining of the SOC value of the battery to be corrected and the determination of whether the SOC value of the battery to be corrected reaches a preset charging threshold, the method further comprises:
when the SOC value of the battery to be corrected does not reach a preset charging threshold value, judging whether a battery charging stopping instruction is obtained or not;
and when the battery charging stopping instruction is not acquired, returning to the step of acquiring the SOC value of the battery to be corrected and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value.
8. A correction apparatus of a battery system, characterized in that the correction apparatus of the battery system comprises: a memory, a processor and a battery system modification program stored on the memory and running on the processor, the battery system modification program, when executed by the processor, implementing the steps of the battery system modification method according to any one of claims 1 to 7.
9. A storage medium having stored thereon a modification program of a battery system, the modification program of the battery system realizing the steps of the modification method of the battery system according to any one of claims 1 to 7 when executed by a processor.
10. A correction device of a battery system, characterized in that the correction device of the battery system comprises:
the acquisition module is used for acquiring a charging correction flag bit and a corresponding pre-stored battery SOC correction difference value in the charging process;
the judging module is used for acquiring the SOC value of the battery to be corrected and judging whether the SOC value of the battery to be corrected reaches a preset charging threshold value;
the acquisition module is further configured to acquire a charging SOC value that maintains the SOC value of the battery to be corrected at a preset charging threshold value state when the SOC value of the battery to be corrected reaches the preset charging threshold value;
and the correction module is used for offsetting the pre-stored SOC correction difference value according to the charging SOC value so as to realize the correction of the battery system.
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