KR101930647B1 - Apparatus and Method for Estimating Capacity of Battery Using Second Order Differential Voltage Curve - Google Patents

Abstract

The present invention provides an apparatus for diagnosing an internal short circuit of a battery which can estimate internal short circuit resistance of a battery by using a state of change (SOC) of the battery by self-discharge when the internal short circuit resistance of the battery occurs. The apparatus for diagnosing an internal short circuit of a battery comprises: a modeling unit to model a test battery with an equivalent circuit model including a voltage source having an open circuit voltage (OCV) and internal resistance connected to the voltage source in series; an open circuit voltage estimation unit to set a load current applied to the test battery as a regressor of the equivalent circuit model, and use an estimation terminal voltage acquired by applying the regressor to the equivalent circuit model and a measurement terminal voltage measured at the test battery to estimate the open circuit voltage; a state-of-charge determination unit to determine a state of charge (SOC) of the test battery corresponding to the estimated open circuit voltage; and an internal short circuit resistance calculation unit to use the determined state of charge to calculate internal short circuit resistance when calculation time for the internal short circuit resistance comes.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus and a method for diagnosing an internal short circuit of a battery,

The present invention relates to battery management, and more particularly, to diagnosis of a battery.

In the case of a conventional battery, an internal short circuit may occur due to a defect in the manufacturing process or an over discharge or overcharge occurring when the battery is used. If an internal short occurs, the battery will degrade due to self-discharge. As the internal short circuit increases, heat generated inside the battery can cause dangerous situations such as heat runaway accompanied by explosion and fire. Therefore, it is very important to diagnose the short-circuit inside the battery early so that the user can know when to replace the battery.

Due to this importance, many techniques have been proposed for diagnosing internal battery shorts. Among them, Xia, B. Multiple cell lithium-ion battery system electric fault online diagnostics. In Proceedings of the 2015 IEEE Transportation Electrification Conference and Expo (ITEC), Dearborn, MI, USA, 14-17 June 2015; 1 -7) has proposed a method of diagnosing an internal short circuit by setting a threshold value using a phenomenon in which terminal voltage decreases and internal heat increases when an internal short circuit occurs in the battery. However, in order to obtain the threshold value, there is a disadvantage in that a preliminary experiment for generating an arbitrary internal short circuit in the battery is required.

Therefore, to overcome the disadvantages of the method presented in the prior art document 1, internal shorting techniques based on parameter estimation using a battery equivalent circuit model have been proposed. Among them, a battery having a normal battery and an equivalent circuit of an internal short-circuited battery is described in a prior art 2 (Ouyang, M. Internal battery short-circuit detection for battery pack using equivalent parameter and consistency method, J. Power Sources 2015, 294 , We have proposed a method of diagnosing an internal short circuit by estimating characteristic parameters using a model. However, this method has disadvantages in that it can be used only in a situation where one battery having an internal short circuit and several normal batteries are connected in series, and the terminal voltage of all the batteries must be measured and provided.

Another prior art document 3 (Feng, X. Online internal short circuit detection for a large format lithium ion battery, Appl . Energy 2016, 161 , 168-180) describes an equivalent circuit model of a normal battery when an internal short- A method of diagnosing an internal short circuit using a parameter change estimated from a thermal equilibrium equation has been proposed. However, this method has a disadvantage in that it is difficult to accurately diagnose an internal short circuit because the degree of parameter change depends on the type of load current applied to the battery.

Therefore, a new method for accurately diagnosing an internal short circuit of the battery is required.

Prior Art 1: Xia, B. Multiple cell lithium-ion battery system electric fault online diagnostics. In Proceedings of the 2015 IEEE Transportation Electrification Conference & Expo (ITEC), Dearborn, MI, USA, 14-17 June 2015; 1-7 pages Prior art 2: Ouyang, M. Internal short circuit detection for battery pack using equivalent parameter and consistency method. J. Power Sources 2015, 294, pp. 272-283 Prior Art 3: Feng, X. Online internal short circuit detection for a large format lithium ion battery. Appl. Energy 2016, 161, 168-180

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems and it is an object of the present invention to provide a battery internal short circuit diagnosis device and method capable of estimating an internal short circuit resistance of a battery using a change in SOC of a battery due to a self- As a technical feature thereof.

Another aspect of the present invention is to provide an apparatus and method for diagnosing an internal short circuit in a battery, which can determine the degree of failure due to an internal short circuit of the battery based on a change in internal short circuit resistance of the battery.

It is another feature of the present invention to provide an apparatus and method for diagnosing an internal battery short circuit that can update a battery equivalent circuit model based on an initial value of an internal short circuit resistance of a battery.

According to an aspect of the present invention, there is provided an apparatus for diagnosing an internal short circuit in a battery, the apparatus comprising: a test battery having an equivalent circuit model including a voltage source having an open circuit voltage (OCV) and an internal resistance connected in series to the voltage source; A modeling unit for modeling the object; A load current to be applied to the test battery is set to a regressor of the equivalent circuit model and an estimated terminal voltage obtained by applying the regenerator to the equivalent circuit model and a measurement terminal voltage measured in the test battery are used An open circuit voltage estimator for estimating the open circuit voltage; A charge state determiner for determining a state of charge (SOC) of the test battery corresponding to the estimated open circuit voltage; And an internal short-circuit resistance calculating unit for calculating the internal short-circuiting resistance using the determined charging state when the internal short-circuiting resistance is calculated.

According to another aspect of the present invention, there is provided a method of diagnosing an internal short circuit of a battery, comprising: obtaining a measurement terminal voltage of the test battery by applying a load current to the test battery; Obtaining an estimated terminal voltage by applying a regenerator in which the load current is defined in a matrix, to an equivalent circuit model of the test battery, which is composed of a voltage source having an open circuit voltage and an internal resistance connected in series to the voltage source; Estimating the open circuit voltage using the estimated terminal voltage and the measured terminal voltage, and determining a state of charge (SOC) of the test battery corresponding to the estimated open circuit voltage; And calculating the internal short-circuiting resistance using the determined charging state when the internal short-circuiting resistance is calculated.

According to the present invention, since the internal short-circuit resistance of the battery is estimated using the change in the state of charge (SOC) of the battery due to the self-discharge phenomenon in the event of an internal short circuit of the battery, the accuracy of the estimated internal short- .

In addition, according to the present invention, the degree of failure of a battery due to an internal short circuit is classified on the basis of a change in internal short-circuit resistance of the battery, and the result is notified to the user at an early stage, There is an effect that the risk of explosion due to runaway can be prevented in advance.

Further, according to the present invention, the battery equivalent circuit model is updated based on the initial value of the battery internal short-circuit resistance, and the battery internal short-circuit resistance is updated using the updated battery equivalent circuit model, so that the estimation error of the battery internal short- It is effective.

1 is a block diagram schematically illustrating a configuration of an apparatus for diagnosing an internal short circuit of a battery according to an embodiment of the present invention.
2 is a diagram showing an example of a load current waveform applied to a test battery.
3 is a diagram showing an initial equivalent circuit model composed of a voltage source and an internal resistance.
4 is a diagram showing an example of an open-circuit voltage-charge state curve.
5 is a diagram showing an updated equivalent circuit model composed of a voltage source, an internal resistor, and an internal short-circuiting resistor.
FIG. 6 is a flowchart illustrating an in-battery short circuit diagnosis method according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The meaning of the terms described herein should be understood as follows.

The word " first, " " second, " and the like, used to distinguish one element from another, are to be understood to include plural representations unless the context clearly dictates otherwise. The scope of the right should not be limited by these terms.

It should be understood that the terms "comprises" or "having" does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

It should be understood that the term " at least one " includes all possible combinations from one or more related items. For example, the meaning of " at least one of the first item, the second item and the third item " means not only the first item, the second item or the third item, but also the second item and the second item among the first item, Means any combination of items that can be presented from more than one.

1 is a block diagram schematically illustrating a configuration of an apparatus for diagnosing an internal short circuit of a battery according to an embodiment of the present invention. 1, an apparatus 100 for diagnosing an internal battery short circuit according to an embodiment of the present invention includes a current applying unit 110, a measurement terminal voltage obtaining unit 120, a modeling unit 130, An estimating unit 140, a charge state determining unit 150, and an internal short-circuit resistance calculating unit 160. [ The apparatus for diagnosing an internal short circuit of a battery 100 according to an embodiment of the present invention may further include a model updating unit 170, a storage unit 180, and a failure diagnosis unit 190.

The current application unit 110 charges the test battery 105 by applying a load current to the test battery 105. [ In one embodiment, the current applicator 110 may continuously apply a load current having a single waveform to the test battery 105. [ At this time, the conditions of the single waveform must be such that the current fluctuation frequency is higher than a predetermined reference speed so that the accurate open circuit voltage can be estimated by the open circuit voltage estimating unit 140, and the measured sample speed must be sufficiently fast as compared with the current fluctuation. FIG. 2 shows a current waveform applied to the test battery 105 by the current applying unit 110 according to the present invention.

The measuring terminal voltage obtaining unit 120 obtains a terminal voltage (hereinafter referred to as a measuring terminal voltage) generated in the test battery 105 by applying a load current to the test battery 105 by the current applying unit 110, . The measurement terminal voltage acquisition unit 120 provides the obtained measurement terminal voltage to the open circuit voltage estimation unit 140. [

The modeling unit 130 models the test battery 105 as an equivalent circuit model (hereinafter referred to as an 'initial equivalent circuit model'). 3, the modeling unit 130 may include a voltage source 310 having an open circuit voltage and an internal resistor 320, R connected in series to the voltage source 310, Can be modeled as an equivalent circuit model. Since the internal short-circuiting resistance of the test battery 105 has a value much larger than the internal resistance, the modeling unit 130 can model the test battery 105 as shown in FIG.

From the equivalent circuit model as shown in FIG. 3, the relationship as described in the following equation is derived.

는 등가회로모델을 통해 추정에 의해 획득되는 추정단자전압을 나타내고,

는 등가회로모델을 통해 추정할 개방회로전압을 나타내며, R은 내부저항을 나타내고, I(k)는 부하전류를 나타낸다.In Equation (1)

Represents an estimated terminal voltage obtained by estimation through an equivalent circuit model,

Represents an open circuit voltage to be estimated through an equivalent circuit model, R represents an internal resistance, and I (k) represents a load current.

 The following equation (2) is derived by summarizing Equation (1) as a determinant.

The open circuit voltage estimating unit 140 estimates the open circuit voltage (OCV) using the recursive least squares method based on the load current, the measurement terminal voltage, and the equivalent circuit model. For application of the cyclic least squares method, the open circuit voltage estimator 140 defines a regressor using the following Equation 3 and defines parameters using Equation 4. [

는 부하전류에 관련된 행렬식으로 정의되는 회귀자를 나타내고,

는 추정대상이 되는 개방회로전압과 내부저항에 관련된 행렬식으로 정의되는 매개변수를 나타낸다. In Equation 3,

Represents a regressor defined by a determinant related to the load current,

Represents a parameter defined by a determinant related to an open circuit voltage and an internal resistance to be estimated.

Accordingly, Equation (2) is summarized as Equation (5) below.

는 부하전류 및 측정단자전압을 포함하는 샘플이 얻어질 때마다 아래의 수학식 6에 따라 갱신된다.At this time, the parameters defined in Equation 4

Is updated according to Equation (6) below whenever a sample including the load current and the measurement terminal voltage is obtained.

In Equation (6), P (K-1) represents the covariance and can be obtained based on Equation (7) below. E (k) is the difference between the measured terminal voltage and the estimated terminal voltage corresponding to the output of the equivalent circuit model Lt; RTI ID = 0.0 > (8) < / RTI >

Under the above-described conditions, the open circuit voltage estimator 140 calculates a parameter for minimizing the sum of the squares of the output error values for n samples by using the recursive least squares method with the following equation (9) as an objective function: . In this case, for application of the cyclic least squares method, the open circuit voltage estimator 140 may set the initial measurement terminal voltage and an arbitrary predetermined resistance value to the initial values of the open circuit voltage and the internal resistance, respectively.

In Equation (9), J (n) denotes an objective function applied to n samples, and? Denotes a forgetting factor. At this time,? Is set such that the reliability of the measurement data of the cyclic least squares method can occupy a high specific gravity of the data at the measurement point close to the present point in time. For example, lambda may be set to a value close to 1, with a value between 0 and 1. For example, for a 0.1 second periodic sample, lambda may be set to 0.995.

The open circuit voltage estimating unit 140 may estimate the open circuit voltage and the internal resistance together using Equation (9).

The charge state determination unit 150 determines the state of charge (SOC) of the test battery 105 corresponding to the open circuit voltage using the open circuit voltage estimated by the open circuit voltage estimator 140 . In one embodiment, the charge state determination unit 150 determines a state of charge that matches an open circuit voltage on an open-circuit voltage-charge state curve calculated in advance using a new battery that has not been used, Can be determined. One example of an open-circuit voltage-charge state curve is shown in FIG.

In another embodiment, since the open circuit voltage and the charge state can be approximated in reciprocal relationship, the charge state determination unit 150 may determine the inverse value of the open circuit voltage to be the charge state corresponding to the estimated open circuit voltage .

The internal short-circuit resistance calculating unit 160 calculates the internal short-circuit resistance of the test battery 105 using the total capacity, the load current, the measurement terminal voltage, and the charging state of the test battery 105 at the time of calculation of the internal short- . In one embodiment, the internal short-circuit resistance calculating section 160 can calculate the internal short-circuit resistance using the following equation (10).

I (n) represents the load current of the n-th sample, and Vt (n) represents the load current of the n-th sample. In the equation, R _ISC represents the internal short- circuit resistance, Cmax represents the total capacity of the test battery 105, T represents the sampling period, ) Represents the measurement terminal voltage of the n-th sample, SOC (1) represents the first charge state (charge state initial value) determined based on the estimated open circuit voltage, SOC Lt; RTI ID = 0.0 > open-circuit < / RTI > voltage.

In one embodiment, the internal short-circuit resistance calculation unit 160 compares the state of charge determined by the state-of-charge determination unit 150 with a predetermined state of charge state reference value. When the determined state of charge is below the state of charge state reference value, It can be determined that the time has arrived. The reason why the internal short-circuit resistance calculating unit 160 according to the present invention calculates the internal short-circuiting resistance when the determined charging state is less than the reference value is that the determined charging state is below the reference value because the self-discharge phenomenon This means that the state of charge of the test battery 105 has been reduced by the power supply voltage.

When the internal short-circuit resistance of the test battery 105 is calculated by the internal short-circuit resistance calculating unit 160, the model updating unit 170 updates the initial equivalent circuit modeled by the modeling unit 120 using the calculated internal short- Update the model. The model updating unit 170 operates from the time when the internal short-circuiting resistance calculating unit 160 calculates the internal short-circuiting resistance.

Specifically, the model updating unit 170 updates the initial equivalent circuit model as shown in Fig. 3 to an equivalent circuit model as shown in Fig. 3 is replaced by a voltage source 310 having an open circuit voltage, an internal resistor 320, R connected in series with the voltage source 310, and an internal resistor 320, And an internal short-circuiting resistor (330, R _ISC ) connected in parallel with the equivalent circuit model. The model updating unit 170 models the test battery 105 as an equivalent circuit model including the internal short-circuit resistance first calculated by the internal short-circuit resistance calculating unit 160.

An additional relationship is derived from the updated equivalent circuit model as shown in FIG. 5 as described in the following equation.

는 부하전류를 나타내고,

는 내부저항에 흐르는 전류를 나타내며,

는 내부단락저항에 흐르는 전류를 나타낸다.In the above equation

Represents the load current,

Represents the current flowing in the internal resistance,

Represents the current flowing in the internal short-circuiting resistor.

Accordingly, the regressor defined in Equation (3) is updated as shown in Equation (15) below.

As described above, according to the present invention, the model updating unit 170 remodels the battery equivalent circuit model based on the internal short-circuit resistance initially calculated by the internal short-circuit resistance calculating unit 160, The battery internal short circuit resistance is updated using the open circuit voltage and the charge state obtained based on the remodeled equivalent circuit model, so that the estimation error of the battery internal short circuit resistance can be reduced.

On the other hand, in accordance with the present invention, the model updating unit 170 updates the internal short-circuiting resistance of the internal short- The model update is repeatedly performed by replacing the internal short-circuit resistance of the equivalent circuit model as shown with the updated internal short-circuit resistance.

와 공분산

이 저장된다. The storage unit 180 stores n open circuit voltages estimated by the open circuit voltage estimating unit 130, n load currents, n measurement terminal voltages, n charged state of charge, n internal shorting resistances, Parameters for renewal when applying the cyclic least squares method

And covariance

Is stored.

The failure diagnosis unit 190 calculates an average value of internal short-circuit resistances calculated during a predetermined period of time stored in the storage unit 180 and calculates an average value of the internal short- To diagnose the degree of failure.

In one embodiment, the failure diagnosis unit 190 may determine that an internal short circuit of the test battery 105 has occurred when the average value of the internal shorting resistances is equal to or greater than the first reference value, and notifies the user of the occurrence of the internal short circuit. As described above, according to the present invention, since it is possible to determine whether an internal short circuit has occurred through the failure diagnosis unit 190, it is possible to prevent a battery performance deterioration due to an internal short circuit and an explosion risk due to thermal runaway .

Hereinafter, a method for diagnosing an internal short circuit of a battery according to the present invention will be described. 6 is a flowchart illustrating a method for diagnosing an internal short circuit of a battery according to an embodiment of the present invention. The internal battery short-circuit diagnosis method shown in FIG. 6 may be performed by an internal battery short-circuit diagnosis apparatus having a configuration as shown in FIG.

As shown in FIG. 6, the battery internal short-circuit diagnosis apparatus obtains the measurement terminal voltage of the test battery by applying a load current to the test battery (S600). At this time, the current applied to the test battery may be a single waveform, and an example is shown in Fig.

Thereafter, the battery internal short-circuit diagnosis apparatus determines whether or not the load current is determined in an equivalent circuit model of a test battery (hereinafter, referred to as an 'initial equivalent circuit model') composed of a voltage source having an open circuit voltage and an internal resistance connected in series to a voltage source The regenerator is applied to obtain the estimated terminal voltage (S610). At this time, the regressor is defined by the above-described Equation (4) and the estimated terminal voltage is defined by Equations (2) and (5).

Thereafter, the battery internal short-circuit diagnosis device estimates the open-circuit voltage using the estimated terminal voltage and the measured terminal voltage (S620). In one embodiment, the battery internal short circuit diagnosis apparatus can estimate the open circuit voltage using the circulating least squares method using the function described in Equation (9) as an objective function. At this time, the parameter to be estimated using the cyclic least squares method can be defined as a determinant of the open circuit voltage and the internal resistance as shown in Equation (4).

Thereafter, the battery internal short-circuit diagnosis apparatus determines the state of charge of the test battery corresponding to the open circuit voltage estimated in S620 (S630). In one embodiment, the in-battery short-circuit diagnostics device may determine a state of charge that is matched to an open-circuit voltage on a pre-calculated open-circuit voltage-charge state curve using a new battery to a state of charge corresponding to the open circuit voltage .

In another embodiment, the battery internal short circuit diagnostic apparatus may determine the inverse value of the open circuit voltage as a charge state corresponding to the open circuit voltage.

Thereafter, the battery internal short-circuit diagnosis device determines whether or not an internal short-circuit resistance calculation time has come (S640). In one embodiment, the battery internal short-circuit diagnosis apparatus can determine whether or not an internal short-circuiting resistance calculation time point has arrived by comparing the charge state determined in S630 with a predetermined charge state reference value.

As a result of the determination, if the determined charge state is equal to or less than the charge state reference value, the battery short circuit diagnosis device determines that the internal short circuit resistance calculation time has come, and calculates the internal short circuit resistance of the test battery at step S650. The internal short-circuit diagnosis device calculates the internal short-circuit resistance using the total capacity of the test battery, the load current, the measurement terminal voltage, and the state of charge. In one embodiment, the battery internal short circuit diagnosis apparatus can calculate the internal short circuit resistance of the battery using Equation (10).

On the other hand, if the determined charge state exceeds the charge state reference value, the battery internal short-circuit diagnosis device returns to S620 to continuously estimate the open circuit voltage.

Thereafter, the battery internal short circuit diagnosis apparatus updates the initial equivalent circuit model using the internal short-circuit resistance calculated in S650 (S660). Specifically, the battery internal short circuit diagnosis device updates the initial equivalent circuit model with an equivalent circuit model composed of a voltage source having an open circuit voltage and an internal resistor connected in series to the voltage source and an internal short circuit resistor connected in parallel with the internal resistor.

Thereafter, the in-battery short-circuit diagnosis device estimates the open-circuit voltage using the measured terminal voltage and the estimated terminal voltage obtained from the updated equivalent circuit model (S670), and determines the charged state of the test battery corresponding to the estimated open- (S680). The internal short circuit resistance of the test battery is calculated using the determined charging state, the total capacity of the test battery, the measurement terminal voltage, and the load current (S690).

Thereafter, the battery internal short-circuit diagnosis apparatus determines whether a predetermined period of time has elapsed (S700). If it is determined that the predetermined period has not elapsed, the procedure returns to S660 and repeats the subsequent steps.

On the other hand, if it is determined that the predetermined period has elapsed as a result of the determination in S700, the in-battery short circuit diagnosis apparatus calculates an average value of the battery internal short-circuit resistances calculated during the corresponding period (S710), and based on the calculated average value of the internal short- And determines the degree of failure of the test battery (S730)

In one embodiment, the internal battery short-circuit diagnosis apparatus may determine that an internal short-circuit of the test battery 105 has occurred when the average value of the internal short-circuiting resistance is equal to or greater than the first reference value, and notify the user thereof. As described above, according to the present invention, it is possible to accurately diagnose the occurrence of an internal short circuit through the failure diagnosis unit 190, thereby preventing a battery performance deterioration due to an internal short circuit and an explosion risk due to thermal runaway .

It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof.

It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: Battery short circuit diagnostic device 105: Test battery
110: current application unit 120: measurement terminal voltage acquisition unit
130: modeling unit 140: open circuit voltage estimating unit
150: charge state determining unit 160: internal short circuit resistance calculating unit
170: Model update unit 180:
190:

Claims (16)

A modeling unit for modeling the test battery as an equivalent circuit model composed of a voltage source having an open circuit voltage (OCV) and an internal resistance connected in series to the voltage source;
A load current to be applied to the test battery is set to a regressor of the equivalent circuit model and an estimated terminal voltage obtained by applying the regenerator to the equivalent circuit model and a measurement terminal voltage measured in the test battery are used An open circuit voltage estimator for estimating the open circuit voltage;
A charge state determiner for determining a state of charge (SOC) of the test battery corresponding to the estimated open circuit voltage; And
And an internal short-circuit resistance calculation unit for calculating the internal short-circuit resistance using the determined charging state when the internal short-circuiting resistance calculation time is reached. The method according to claim 1,
The open-circuit voltage estimating unit may calculate the open- The open circuit voltage is estimated using a Recursive Least Squares method,
Wherein J (n) denotes an objective function applied to n samples,? Denotes a weight value, y (k) denotes the measurement terminal voltage,

The

Lt; RTI ID = 0.0 > of: < / RTI &

Represents the regressor,

Represents a parameter defined by the open circuit voltage and a matrix value for the internal resistance. The method according to claim 1,
Wherein the charge state determining unit determines the charge state matched with the open circuit voltage on the open circuit voltage-charge state curve calculated in advance using the new battery as the charge state corresponding to the open circuit voltage. Short-circuit diagnosis device. The method according to claim 1,
Wherein the charge state determining unit determines the inverse value of the open circuit voltage to be a charge state corresponding to the open circuit voltage. The method according to claim 1,
The internal short-circuit resistance calculating section calculates the internal short-

To calculate the internal short circuit resistance,
In the equation R _ISC denotes the internal short-circuit resistance, Cmax represents the total capacity of the test battery, T denotes a sampling period, I (n) denotes a load current of the n-th sample, Vt (n) is SOC (k) represents the measured terminal voltage of the n-th sample, SOC (1) represents the charge state initial value determined based on the estimated open circuit voltage, and SOC And the battery state of the battery is determined to be a charged state. The method according to claim 1,
Wherein the internal short-circuit resistance calculating unit compares the determined charging state with a predetermined charging state reference value, and determines that the internal short-circuiting resistance calculating time comes when the determined charging state becomes the charging state reference value or less. Short-circuit diagnosis device. The method according to claim 1,
Wherein the modeling unit updates the equivalent circuit model to an equivalent circuit model composed of the voltage source, an internal resistance connected in series to the voltage source, and an internal shorting resistor connected in parallel to the internal resistance,
Wherein the open circuit voltage estimating unit estimates the open circuit voltage using the updated equivalent circuit model. The method according to claim 6,
A storage section for storing internal short-circuit resistances calculated for a predetermined time; And
Further comprising a failure diagnostic unit for determining a failure level of the test battery based on an average value of internal short-circuit resistances during the corresponding period. Obtaining a measurement terminal voltage of the test battery by applying a load current to the test battery;
Obtaining an estimated terminal voltage by applying a regenerator in which the load current is defined in a matrix, to an equivalent circuit model of the test battery, which is composed of a voltage source having an open circuit voltage and an internal resistance connected in series to the voltage source;
Estimating the open circuit voltage using the estimated terminal voltage and the measured terminal voltage, and determining a state of charge (SOC) of the test battery corresponding to the estimated open circuit voltage; And
And calculating the internal short-circuiting resistance using the determined charging state when the internal short-circuiting resistance is calculated. 10. The method of claim 9,
In the determining step,
Equation

(N) represents an objective function applied to n samples, lambda represents a weight, and y (k) represents a weight function of the open circuit voltage using the recursive least squares method, Represents the measurement terminal voltage,

The

Lt; RTI ID = 0.0 > of: < / RTI &

Represents the regressor,

Wherein the open circuit voltage and the internal resistance represent a parameter defined in a matrix. 10. The method of claim 9,
Wherein the determining step determines the state of charge that matches the open circuit voltage on the open circuit voltage-charge state curve calculated in advance using the new battery to a state of charge corresponding to the open circuit voltage. Internal short-circuit diagnosis method. 10. The method of claim 9,
Wherein the determining step determines the inverse value of the open circuit voltage to be a charge state corresponding to the open circuit voltage. 10. The method of claim 9,
In the step of calculating the internal short-circuiting resistance,
Equation

Using calculating the internal short-circuit resistance, the equation R _ISC denotes the internal short-circuit resistance, Cmax represents the total capacity of the test battery, T denotes a sampling period, I (n) is the n-th sample , SOC (1) represents the initial state of charge state determined based on the estimated open-circuit voltage, and SOC (k) represents the load current of the k-th sample Wherein the state of charge is determined based on an estimated open circuit voltage for the sample. 10. The method of claim 9,
Further comprising the step of comparing the determined charge state with a predetermined charge state reference value to determine whether or not the internal short-circuiting resistance calculation time comes,
Wherein the step of calculating the internal short-circuit resistance is performed when the determined charging state is equal to or less than the charging state reference value. 10. The method of claim 9,
Further comprising the step of updating the equivalent circuit model with an equivalent circuit model consisting of the voltage source, an internal resistance connected in series to the voltage source, and an internal shorting resistor connected in parallel to the internal resistance,
And estimating the open circuit voltage using the updated equivalent circuit model in the determining step. 16. The method of claim 15,
Calculating an average value of internal short-circuit resistances calculated for a predetermined time; And
Further comprising: determining a failure level of the test battery based on an average value of the internal short-circuit resistances.

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