KR-20260063569-A - SYSTEM AND METHOD FOR ESTIMATING STATE OF HEALTH OF BATTERY FOR VEHICLE

KR20260063569AKR 20260063569 AKR20260063569 AKR 20260063569AKR-20260063569-A

Abstract

A vehicle battery life prediction system according to an embodiment of the present specification includes: a battery sensor that acquires state data of a battery; and a control unit that measures a battery voltage drop based on the state data of the battery and predicts the life of the battery based on the correlation between the voltage drop and capacity in the battery component characteristics stored in advance.

Inventors

임영철

Assignees

현대자동차주식회사
기아 주식회사

Dates

Publication Date: 20260507
Application Date: 20241030

Claims (13)

A battery sensor that acquires battery status data; A control unit that measures the battery voltage drop based on the state data of the battery and predicts the life of the battery based on the correlation between the voltage drop and capacity in the previously stored battery component characteristics; A vehicle battery life prediction system including
In paragraph 1, The above control unit is, A vehicle battery life prediction system that, when it is determined that the vehicle ignition is turned off, senses the State of Charge (SOC) of the battery based on the state data of the battery, and if the SOC of the battery is below a first reference value, charges the battery to have an SOC value greater than or equal to a second reference value.
In paragraph 2, The above control unit is, A vehicle battery life prediction system that charges the battery to have an SOC value greater than or equal to the second reference value, and then discharges a certain current for a certain period of time to periodically measure the voltage drop of the battery.
In paragraph 3, The above control unit is, A vehicle battery life prediction system that measures the voltage drop by discharging the battery after the battery is fully charged and after the battery is left undischarged for a preset period of time.
In paragraph 3, The above control unit is, A vehicle battery life prediction system that discharges the battery in the power-on (IG ON) state for the in-vehicle controller.
In paragraph 3, The above control unit is, A vehicle battery life prediction system that compares the measured voltage drop of the battery with the voltage drop and capacity of the battery component characteristics to calculate the battery capacity for each voltage drop, and determines the point in time that matches the voltage drop at the end of life standard of the battery component characteristics as the end of life of the battery.
In paragraph 3, The above battery component characteristics include a battery component characteristic of Dod (Depth of discharge) 17.5%, and is a vehicle battery life prediction system.
In paragraph 1, The above battery sensor is, A vehicle battery life prediction system comprising at least one of a current sensing unit, a SOC sensing unit for sensing the SOC (State of charge) of the battery, a voltage sensing unit, and a temperature sensing unit.
In paragraph 1, A vehicle battery life prediction system in which the voltage drop increases and the capacity decreases as the battery's durability progresses.
When the vehicle ignition is turned off, the state of charge (SOC) of the battery is sensed, and if the SOC of the battery is below a first reference value, the battery is charged to have an SOC value greater than or equal to a second reference value; A step of periodically measuring the voltage drop of the battery by discharging a constant current for a certain period of time; and A step of predicting the life of the battery based on the correlation between the measured voltage drop and the voltage drop and capacity in the previously stored battery component characteristics; A control method for a vehicle battery life prediction system including
In Paragraph 10, A control method for a vehicle battery life prediction system that further includes the step of leaving the battery unattended for a preset time after the battery is fully charged.
In Paragraph 10, The step of periodically measuring the voltage drop of the battery by discharging the above constant current for a certain period of time is A control method for a vehicle battery life prediction system, wherein the battery is discharged while the power to the in-vehicle controller is in an ON state.
In Paragraph 10, The step of predicting the life of the battery based on the correlation between the voltage drop measured above and the voltage drop and capacity in the previously stored battery component characteristics is, A control method for a vehicle battery life prediction system comprising the step of comparing the measured voltage drop with the voltage drop and capacity in the battery component characteristics to calculate the battery capacity for each voltage drop, and determining the point in time that matches the voltage drop at the end of life standard in the battery component characteristics as the end of life time of the battery.

Description

System and Method for Estimating State of Health of Battery for Vehicle This specification relates to a vehicle battery life prediction system and a control method thereof. Electric vehicles utilize not only high-voltage batteries to supply power during driving, but also low-voltage batteries to power various power-consuming devices. Low-voltage batteries can serve as an entry switch for the initial use of the high-voltage battery and can supply power to vehicle electrical components and devices for convenience functions. Predicting battery life is very important because the end of a battery's life not only causes the cessation of electrical components but also affects the vehicle's operation. Accordingly, research is continuing to provide reliable battery information by accurately predicting battery life. FIG. 1 is a control block diagram of a vehicle battery life prediction system according to one embodiment. Figure 2 is a diagram illustrating the correlation between the battery's lifespan, voltage drop characteristics during discharge, and the battery's capacity. FIGS. 3 and 4 are control flow diagrams of a vehicle battery life prediction system according to one embodiment. FIG. 5 is a diagram illustrating the result of generating a battery voltage drop trend line of a vehicle battery life prediction system according to one embodiment. Figures 6 and 7 are diagrams illustrating the correlation between the lifespan of a battery with a DOD of 17.5%, the voltage drop characteristics during discharge, and the capacity of the battery. Hereinafter, to specifically explain the present invention, embodiments will be described, and to facilitate understanding of the invention, the invention will be described in detail with reference to the accompanying drawings. In describing the embodiments disclosed in this specification, if it is determined that a detailed description of related prior art may obscure the essence of the embodiments disclosed in this specification, such detailed description will be omitted. Furthermore, the accompanying drawings are intended only to facilitate understanding of the embodiments disclosed in this specification, and the technical concept disclosed in this specification is not limited by the accompanying drawings; it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and technical scope of the invention. Terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but said components are not limited by said terms. These terms are used solely for the purpose of distinguishing one component from another. When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. On the other hand, when it is stated that one component is "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between. A singular expression includes a plural expression unless the context clearly indicates otherwise. In this specification, terms such as “comprising” or “having” are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not excluding in advance the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof. According to the embodiments of the present specification, the lifespan of a battery can be predicted by utilizing the characteristic that as the battery ages, the full charge capacity decreases and the voltage drop during discharge increases. In one embodiment, the battery voltage drop can be measured by utilizing a battery constant recharge function after the ignition is turned off to charge the battery to a high-capacity range, allowing the battery voltage to stabilize by leaving it for a certain period of time, and then discharging a certain current while in the IG ON state to check the difference in battery voltage before and after discharge. Accordingly, the end of the battery's lifespan can be predicted by utilizing the correlation between the actually measured battery voltage drop and the voltage drop and capacity in the previously stored battery component characteristics. Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. FIG. 1 is a control block diagram of a vehicle battery life prediction system according to one embodiment, and FIG. 2 is a diagram for explaining the correlation between the battery life, voltage drop characteristics during discharge, and the battery capacity. Referring to FIG. 1, a vehicle battery life prediction system according to an embodiment of the