Method, system, medium and device for safety control of ternary lithium-ion power battery

Abstract

The application provides a kind of ternary lithium ion power battery safety control method and system, belong to power battery safety control technical field.The method includes: according to the mileage corresponding to the cycle number of power battery, determine a plurality of main charging platform area, there are a plurality of transition sub charging platform area between adjacent main charging platform area, each main charging platform area and sub charging platform area correspond to have charging voltage upper limit set value;When mileage reaches the mileage corresponding to main charging platform area or sub charging platform area, control the charging upper limit voltage of power battery is equal to or less than the corresponding charging voltage upper limit set value.The application controls the upper limit of battery charging voltage in the whole life cycle of new energy vehicle in stages, greatly improves the safety performance of power battery.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power battery safety control, in particular to a ternary lithium ion power battery safety control method, system, medium and equipment. BACKGROUND

[0002] The statements in this section merely provide background technology related to the present application and do not necessarily constitute prior art.

[0003] With the development of new energy vehicles and the continuous deepening of electrification, the number of new energy vehicles is increasing year by year, and the energy density of power batteries is more valued by each battery cell factory and main machine factory. The proportion of ternary lithium ion battery shipments is increasing. With the use of a large number of ternary lithium ion batteries in new energy vehicles, the safety accidents caused by safety failures of ternary lithium ion power batteries are increasing, so how to control and use the safety of ternary lithium ion power batteries has become a problem to be solved.

[0004] The inventor found that most of the existing solutions monitor the health status of the power battery through the vehicle-mounted BMS management system, and generally use the same control parameters and strategies in different life stages of the power battery, which does not achieve the purpose of protecting and relieving the aging of the power battery and improving the safety, and does not control the safety of the battery based on the safety characteristics of the battery cell or the battery itself. SUMMARY

[0005] In order to solve the problems of the prior art, the present application provides a ternary lithium ion power battery safety control method, system, medium and equipment, which controls the upper limit of the battery charging voltage in stages in the whole life cycle of the new energy vehicle with the increase of the mileage (corresponding to the battery cycle process), greatly improving the safety performance of the power battery.

[0006] In order to achieve the above purpose, the present application adopts the following technical scheme:

[0007] The first aspect of the present application provides a ternary lithium ion power battery safety control method.

[0008] A ternary lithium ion power battery safety control method, comprising the following process:

[0009] According to the mileage corresponding to the cycle number of the power battery, a plurality of main charging platform areas are determined, and a plurality of transition sub-charging platform areas are arranged between adjacent main charging platform areas. Each main charging platform area and sub-charging platform area respectively corresponds to a charging voltage upper limit setting value;

[0010] When the mileage reaches the mileage corresponding to the main charging platform area or the sub-charging platform area, the upper limit voltage of the power battery is controlled to be equal to or less than the corresponding charging voltage upper limit setting value.

[0011] As a further limitation of the first aspect of the application, the complete charging process and discharging process of the power battery is a cycle, assuming that the upper limit of the charging voltage of the power battery when it is just put into operation is V1, the upper limit of the charging voltage corresponding to the first main charging platform area is set to V1;

[0012] The upper limit of the charging voltage corresponding to the next main charging platform area is less than the upper limit of the charging voltage of any of the previous main charging platform areas.

[0013] As a further limitation of the first aspect of the application, each sub-charging platform area between adjacent two main charging platform areas has a stepwise decrease in the upper limit of the charging voltage with the same decrease amplitude according to the increase of the mileage.

[0014] As a further limitation of the first aspect of the application, when the current upper limit of the charging voltage is the upper limit of the charging voltage corresponding to the last main charging platform area, the control of the upper limit voltage of the power battery is equal to or less than the current upper limit of the charging voltage until the power battery is retired.

[0015] As a further limitation of the first aspect of the application, the SOH values corresponding to different cycle numbers of the power battery are obtained, and in the full life cycle of the power battery, the charging process parameters and the discharging process parameters for the power battery management are multiplied by the SOH values corresponding to the cycle numbers as updated values.

[0016] The second aspect of the application provides a ternary lithium ion power battery safety control system.

[0017] A ternary lithium ion power battery safety control system comprises:

[0018] The charging platform area division module is configured to determine a plurality of main charging platform areas according to the mileage corresponding to the cycle number of the power battery, and there are a plurality of transition sub-charging platform areas between adjacent main charging platform areas, and each main charging platform area and sub-charging platform area correspond to a charging voltage upper limit set value;

[0019] The charging upper limit voltage control module is configured to control the upper limit voltage of the power battery to be equal to or less than the corresponding charging voltage upper limit set value when the mileage reaches the mileage corresponding to the main charging platform area or the sub-charging platform area.

[0020] As a further limitation of the second aspect of the application, the complete charging process and discharging process of the power battery is a cycle, assuming that the upper limit of the charging voltage of the power battery when it is just put into operation is V1, the upper limit of the charging voltage corresponding to the first main charging platform area is set to V1;

[0021] The upper limit of the charging voltage corresponding to the next main charging platform area is less than the upper limit of the charging voltage of any of the previous main charging platform areas.

[0022] As a further limitation of the second aspect of the application, each of the sub-charging platform areas between the adjacent two main charging platform areas has a stepwise decrease in the upper limit of the charging voltage with the same decrease amplitude as the mileage increases.

[0023] As a further limitation of the second aspect of the application, when the current upper limit of the charging voltage is the upper limit of the charging voltage corresponding to the last main charging platform area, the control of the upper limit voltage of the power battery is equal to or less than the current upper limit of the charging voltage until the power battery is retired.

[0024] As a further limitation of the second aspect of the application, the SOH values corresponding to different cycle numbers of the power battery are obtained, and in the full life cycle of the power battery, the charging process parameters and the discharging process parameters for the power battery management are multiplied by the SOH values corresponding to the cycle numbers as the updated values.

[0025] The third aspect of the application provides a computer readable storage medium having a program stored thereon, the program being executed by a processor to implement the steps in the safety control method of the ternary lithium ion power battery according to the first aspect of the application.

[0026] The fourth aspect of the application provides an electronic device comprising a memory, a processor, and a program stored on the memory and executable on the processor, wherein the processor executes the program to implement the steps in the safety control method of the ternary lithium ion power battery according to the first aspect of the application.

[0027] Compared with the prior art, the application has the following advantages:

[0028] 1. The application innovatively proposes a safety control method, system, medium and device for ternary lithium ion power batteries, which controls the upper limit of the battery charging voltage in stages in the full life cycle of a new energy vehicle with the increase of the usage mileage (corresponding to the battery cycle process), greatly improves the safety performance of the power battery, and greatly reduces or solves the safety risk problem of the new energy vehicle.

[0029] 2. The application innovatively proposes a safety control method, system, medium and device for ternary lithium ion power batteries, which introduces the SOH factor coefficient for the fast charging current and the discharging power in the full life cycle of the ternary lithium ion power battery, and updates in real time with different life stages and aging degrees of the battery to maximize the life and safe use of the ternary lithium ion power battery.

[0030] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0031] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0032] Figure 1 This is a flowchart illustrating the safety control method for ternary lithium-ion power batteries provided in Embodiment 1 of the present invention.

[0033] Figure 2 This is a schematic diagram showing the step-down of the upper limit of the charging voltage of a ternary lithium-ion power battery provided in Embodiment 1 of the present invention;

[0034] Figure 3 This is a schematic diagram of the ternary lithium-ion power battery safety control system provided in Embodiment 2 of the present invention. Detailed Implementation

[0035] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0036] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0037] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0038] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0039] Example 1:

[0040] like Figure 1 As shown, Embodiment 1 of the present invention provides a safety control method for ternary lithium-ion power batteries, comprising the following processes:

[0041] S101: Determine a plurality of main charging platform areas according to the mileage corresponding to the cycle number of the power battery, there are a plurality of transition sub-charging platform areas between adjacent main charging platform areas, each main charging platform area and sub-charging platform area correspondingly has a charging voltage upper limit setting value;

[0042] S102: When the mileage reaches the mileage corresponding to the main charging platform area or the sub-charging platform area, control the charging upper limit voltage of the power battery to be equal to or less than the corresponding charging voltage upper limit setting value.

[0043] Specifically, in S1, it includes:

[0044] According to the corresponding mileage of the cycle number of the battery (one complete charging process and discharging process is recorded as one cycle), a plurality of main charging platform areas are formed by dividing stages according to the mileage, a plurality of sub-charging platform areas are arranged between each main charging platform area for transition, and each main charging platform area and sub-charging platform area correspondingly has a charging upper limit voltage setting value;

[0045] When the mileage reaches the mileage corresponding to each platform area (main charging platform area or sub-charging platform area), control the charging upper limit voltage to be the same as the charging upper limit voltage setting value corresponding to the platform area, wherein the main charging platform area is 80,000 kilometers or 100,000 kilometers, the sub-charging platform area controls the mileage to be 0.5-1.5 ten thousand kilometers, and the charging voltage upper limit is controlled to decrease by 10mV per step.

[0046] Specifically, as shown in Figure 2 For example, the initial voltage upper limit V1=4.25V, S1=80,000 kilometers (the first main charging platform area) is run at 4.25V, then reduced by 10mV to run 15,000 kilometers (sub-charging platform area), and then by analogy, through a plurality of charging voltage step-down sub-charging platform areas (the charging upper and lower voltage difference of adjacent sub-charging platform areas is 10mV), until the voltage reaches V2=4.2V, and the mileage reaches S2=140,000 kilometers;

[0047] Then the charging upper limit voltage is kept at 4.2V to run 80,000 kilometers (the second main charging platform area) to S3=220,000 kilometers; then reduced by 10mV to run 10,000 kilometers (sub-charging platform area), and then by analogy, through a plurality of charging voltage step-down sub-charging platform areas (the charging upper and lower voltage difference of adjacent sub-charging platform areas is 10mV), until the voltage reaches V3=4.15V, and the mileage reaches S4=260,000 kilometers;

[0048] Then run 100,000 kilometers at 4.15V (third main charging platform area) to S5=360,000 kilometers, then reduce 10mV run 10,000 kilometers (sub charging platform area), and the next step is to run through multiple charging voltage step-down sub charging platform areas (the charging voltage difference between adjacent sub charging platform areas is 10mV), until the voltage reaches V4=4.10V, and the mileage reaches S6=400,000 kilometers;

[0049] Then keep 4.10V running 10,000 kilometers (the fourth main charging platform area) to S7=500,000 kilometers; then reduce 10mv run 0.5,000 kilometers (sub charging platform area), and the next step is to run through multiple charging voltage step-down sub charging platform areas (the charging voltage difference between adjacent sub charging platform areas is 10mV), until the charging voltage reaches V5=3.9V (the fifth main charging platform area); finally, keep the upper limit of the charging voltage at 3.9V until the ternary lithium ion battery is retired.

[0050] In this embodiment, the cumulative mileage from S1 to S7 is controlled in the range of 40-50 million kilometers to ensure the safe use of the ternary lithium ion battery.

[0051] As shown in Table 1, the cycle number data of the ternary lithium ion battery and the state of health SOH of the ternary battery correspond to each other, which is controlled by the BMS battery management system control strategy, combined with the SOH value in the charging process and the discharging process of the ternary lithium ion power battery in the whole life cycle, multiplied by the SOH value, and updated in real time with the different life stages and aging processes of the battery to ensure the safety of the battery. The BMS management system is a complete cycle according to a complete charging process and a discharging process, and the battery is managed by the updated charging and discharging parameters corresponding to each cycle number.

[0052] Table 1: Correspondence between cycle number data and state of health SOH of ternary battery.

[0053] Cycle number 0 188 263 300 550 650 900 1250 1350 1500 SOH 1 0.975 0.965 0.96 0.93 0.915 0.88 0.83 0.785 0.7

[0054] Example 2:

[0055] As Figure 3 shown, the embodiment 2 of the present application provides a ternary lithium ion power battery safety control system, which comprises:

[0056] The charging platform area division module is configured to determine a plurality of main charging platform areas according to the mileage corresponding to the cycle number of the power battery, a plurality of transition sub charging platform areas between adjacent main charging platform areas, and a charging voltage upper limit setting value corresponding to each main charging platform area and sub charging platform area;

[0057] The charging upper limit voltage control module is configured to control the charging upper limit voltage of the power battery to be equal to or less than the corresponding charging voltage upper limit setting value when the mileage reaches the mileage corresponding to the main charging platform area or the sub-charging platform area.

[0058] Specifically, in the charging platform area division module, the following detailed functions are included:

[0059] The mileage is divided into multiple main charging platform areas in stages according to the mileage corresponding to the cycle number of the battery (one complete charging process and discharging process is recorded as one cycle), multiple sub-charging platform areas are arranged between each main charging platform area for transition, and each main charging platform area and sub-charging platform area is correspondingly provided with a charging upper limit voltage setting value;

[0060] When the mileage corresponding to each platform area (main charging platform area or sub-charging platform area) is reached, the charging upper limit voltage is controlled to be the same as the charging upper limit voltage setting value corresponding to the platform area, wherein the main charging platform area is controlled according to 80,000 kilometers or 100,000 kilometers, the sub-charging platform area is controlled to have a mileage of 0.5-1.5 kilometers, and in addition, the charging voltage upper limit is controlled to decrease by 10 mV in steps.

[0061] The initial voltage V1 is recorded, 80,000 or 100,000 kilometers are run, then the charging voltage upper limit is decreased by 10 mV, 0.5-1.5 kilometers are run, then the same is repeated until the voltage reaches the second main platform area V2, then the second main platform area is maintained for 80,000 or 100,000 kilometers, then the charging voltage upper limit is decreased by 10 mV, 0.5-1.5 kilometers are run, then the same is repeated until the voltage reaches the third main platform area V3, and finally the charging voltage reaches V5, the voltage upper limit is maintained until the retirement, and the cumulative mileage is controlled in the range of 400-500 kilometers.

[0062] In this embodiment, the cycle number data of the ternary lithium ion battery and the state of health SOH of the ternary battery are also obtained, and the BMS battery management system control strategy is used for control, combined with the charging process and discharging process of the SOH value in the whole life cycle of the ternary lithium ion power battery multiplied by the SOH value, which is updated in real time with the different life stages and aging processes of the battery to ensure the safety of the battery, and the BMS management system controls one complete cycle according to one complete charging process and discharging process, and the updated charging and discharging parameters corresponding to each cycle number are used for battery management.

[0063] The embodiment introduces the influence factor coefficient SOH of the full life cycle fast charging current and the discharge power of the ternary lithium ion power battery, updates in real time with different life stages and aging degrees of the battery, and controls the upper limit of the charging voltage of the ternary lithium ion power battery according to the mileage accumulation, so as to maximize the life and safe use of the ternary lithium ion power battery, and greatly reduce or solve the safety risk problem of the new energy vehicle.

[0064] The above merely describes the preferred embodiments of the present application, and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A safety control method for a ternary lithium-ion power battery, characterized in that, The method comprises the following steps: According to the mileage corresponding to the cycle number of the power battery, a plurality of main charging platform areas are determined, there are a plurality of transition sub-charging platform areas between adjacent main charging platform areas, and each main charging platform area and sub-charging platform area correspond to a charging voltage upper limit setting value respectively; When the mileage reaches the mileage corresponding to the main charging platform area or the sub-charging platform area, the charging upper limit voltage of the power battery is controlled to be equal to or less than the corresponding charging voltage upper limit setting value; The SOH values corresponding to different cycle numbers of the power battery are obtained, and in the whole life cycle of the power battery, the charging process parameters and the discharge process parameters used for the management of the power battery are multiplied by the SOH values corresponding to the cycle numbers as updated values; combined with the charging process and the discharge process of the SOH values in the whole life cycle of the ternary lithium ion power battery, the SOH values are multiplied by the SOH values, and the safety of the battery is ensured by real-time updating with different life stages and aging processes of the battery; According to the increase of the mileage, the charging voltage upper limit setting value of each sub-charging platform area between the two adjacent main charging platform areas decreases in a step-down manner with the same decreasing amplitude.

2. The safety control method of the ternary lithium ion power battery according to claim 1, wherein A complete charging process and a discharge process of the power battery are a cycle, and it is assumed that the charging voltage upper limit of the power battery when it is put into operation is V1, and the charging voltage upper limit setting value corresponding to the first main charging platform area is V1; The charging voltage upper limit setting value corresponding to the next main charging platform area is less than the charging voltage upper limit setting value of any main charging platform area before it.

3. The safety control method of the ternary lithium ion power battery according to claim 1, wherein When the current charging voltage upper limit is the charging voltage upper limit setting value corresponding to the last main charging platform area, the charging upper limit voltage of the power battery is controlled to be equal to or less than the current charging voltage upper limit until the power battery is retired.

4. A safety control system for a ternary lithium-ion power battery, characterized in that, It comprises: The charging platform area division module is configured to determine a plurality of main charging platform areas according to the mileage corresponding to the cycle number of the power battery, there are a plurality of transition sub-charging platform areas between adjacent main charging platform areas, and each main charging platform area and sub-charging platform area correspond to a charging voltage upper limit setting value respectively; The charging upper limit voltage control module is configured to control the charging upper limit voltage of the power battery to be equal to or less than the corresponding charging voltage upper limit setting value when the mileage reaches the mileage corresponding to the main charging platform area or the sub-charging platform area; The SOH values corresponding to different cycle numbers of the power battery are obtained, and in the whole life cycle of the power battery, the charging process parameters and the discharge process parameters used for the management of the power battery are multiplied by the SOH values corresponding to the cycle numbers as updated values; combined with the charging process and the discharge process of the SOH values in the whole life cycle of the ternary lithium ion power battery, the SOH values are multiplied by the SOH values, and the safety of the battery is ensured by real-time updating with different life stages and aging processes of the battery; According to the increase of the mileage, the charging voltage upper limit setting value of each sub-charging platform area between the two adjacent main charging platform areas decreases in a step-down manner with the same decreasing amplitude.

5. The safety control system of the ternary lithium-ion power battery according to claim 4, characterized in that, A complete charging process and discharging process of the power battery is a cycle, and assuming that the upper limit of the charging voltage of the power battery when it is just put into operation is VI, the upper limit of the charging voltage corresponding to the first main charging platform region is set as VI; The upper limit of the charging voltage corresponding to the next main charging platform region is less than the upper limit of the charging voltage of any previous main charging platform region.

6. The safety control system of the ternary lithium-ion power battery according to claim 4, characterized in that, When the current upper limit of the charging voltage is the upper limit of the charging voltage corresponding to the last main charging platform region, the upper limit of the charging voltage of the power battery is controlled to be equal to or less than the current upper limit of the charging voltage until the power battery is decommissioned.

7. A computer-readable storage medium having stored thereon a program, characterized in that, The program is executed by the processor to implement the steps in the safety control method of the ternary lithium-ion power battery according to any one of claims 1-3.

8. An electronic device comprising a memory, a processor, and a program stored in the memory and executable on the processor, characterized by The processor executes the program to implement the steps in the safety control method of the ternary lithium-ion power battery according to any one of claims 1-3.

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