WO2019199062A1 - Device, method, battery pack and electrical system for deciding electrode information of battery - Google Patents

Abstract

Provided are a device and a method for deciding electrode information of a battery comprising a first electrode and a second electrode, and a battery pack comprising the device. The device comprises: a sensing unit for measuring the voltage and current of the battery; and a processor. The processor generates a V-dQ/dV curve on the basis of the voltage and current of the battery. The V-dQ/dV curve shows the correlation between V (the voltage of the battery) and dQ/dV (a ratio of the variation (dQ) of a storage capacity with respect to the variation (dV) of the voltage of the battery). The processor detects a plurality of feature points from the V-dQ/dV curve. The processor decides information associated with the first electrode and the second electrode, respectively, as the electrode information on the basis of the plurality of feature points.

Description

Apparatus, methods, battery packs and electrical systems for determining electrode information of batteries

The present invention relates to an apparatus and method for determining information related to a positive electrode and a negative electrode included in a battery, and to a battery pack and an electrical system including the device.

This application is a priority application for Korean Patent Application No. 10-2018-0041692, filed April 10, 2018, and Korean Patent Application No. 10-2019-0041600, filed April 9, 2019. All the contents disclosed in the specification and drawings of this application are incorporated in this application by reference.

Recently, as the demand for portable electronic products such as laptops, video cameras, mobile phones, etc. is rapidly increased, and development of electric vehicles, storage batteries for energy storage, robots, satellites, and the like is in earnest, high-performance batteries capable of repeatedly charging and discharging Research is actively being conducted.

Currently commercialized batteries include nickel cadmium batteries, nickel hydride batteries, nickel zinc batteries, and lithium batteries. Among them, lithium batteries have almost no memory effect compared to nickel-based batteries, and thus are free of charge and discharge, and have a very high self discharge rate. Its low and high energy density has attracted much attention.

Batteries gradually degrade in performance as they are repeatedly charged and discharged. Therefore, it is necessary to measure the electrode potential of the battery in order to confirm the performance of the battery. Conventionally, the three-electrode potential measurement method using the reference electrode is mainly used.

The reference electrode is used to make a battery circuit for measuring the potential in order to measure the potential of the positive electrode or the negative electrode included in the battery, and must satisfy the requirement of having a non-polarization characteristic of maintaining a constant potential value at a constant temperature. do. In addition, since one reference electrode is required per battery, a lot of time may be spent in the manufacturing process of the battery.

The present invention analyzes a plurality of feature points on a V-dQ / dV curve of a battery generated based on a voltage and a current of a battery, thereby providing information on a positive electrode and a negative electrode of the battery (eg, an active material) without utilizing a reference electrode. The purpose of the present invention is to provide an apparatus, a method, a battery pack, and an electrical system capable of determining the type, the potential of a positive electrode or a negative electrode corresponding to a specific storage amount, and the like.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention, which are not mentioned above, can be understood by the following description, and more clearly by the embodiments of the present invention. Also, it will be readily appreciated that the objects and advantages of the present invention may be realized by the means and combinations thereof indicated in the claims.

According to an aspect of the present invention, an apparatus for determining electrode information of a battery including a first electrode and a second electrode includes: a sensing unit configured to measure a voltage of the battery and a current of the battery; And a processor operatively coupled with the sensing unit.

The processor is configured to determine the amount of power storage of the battery based on the current of the battery. The processor may generate a QV curve indicating a relationship between the voltage of the battery and the storage amount of the battery, and V-dQ / dV representing a relationship between the voltage of the battery and the ratio of the change amount of the storage amount to the change amount of the voltage of the battery. Configured to convert to curves. The processor detects a plurality of feature points from the V-dQ / dV curve. The processor is configured to classify each of the plurality of feature points into a first electrode feature point and a second electrode feature point. The processor is configured to determine the type of the first electrode active material and the type of the second electrode active material included in the battery as the electrode information based on the number of the first electrode feature points and the number of the second electrode feature points. .

The processor may be configured to classify each feature point located in a voltage range of a predetermined reference voltage or more among the plurality of feature points as the first electrode feature point. The processor may be configured to classify each feature point positioned in a voltage range less than the reference voltage among the plurality of feature points as the second electrode feature point.

The processor may be configured to obtain a first capacity-potential curve of a reference battery from a memory unit operably coupled to the processor. The processor may be configured to determine, from the first capacitance-potential curve, a first electrode potential of the reference battery corresponding to a storage amount of each first electrode feature point. The processor may be configured to generate a potential of the second electrode of the battery corresponding to a storage amount of each of the first electrode feature points based on the voltage of each of the first electrode feature points and the first electrode potential of the reference battery. It can be configured to determine as information. The reference battery may include the first electrode active material and the second electrode active material.

The processor subtracts the voltage of each of the first electrode feature points from the first electrode potential of the reference battery, thereby subtracting the potential of the second electrode of the battery corresponding to the storage amount of each of the first electrode feature points. It can be configured to determine as information.

The processor may be configured to obtain a second capacity-potential curve of the reference battery from the memory unit. The processor may be configured to determine, from the second capacitance-potential curve, a second electrode potential of the reference battery corresponding to the capacitance of each second electrode feature point. The processor may be configured to generate a potential of the first electrode of the battery corresponding to a storage amount of each of the second electrode feature points based on a voltage of each of the second electrode feature points and the second electrode potential of the reference battery. It can be configured to determine as information.

The processor adds the voltage of each of the second electrode feature points and the second electrode potential of the reference battery, and converts the potential of the first electrode of the battery corresponding to the storage amount of each of the second electrode feature points to the electrode. It can be configured to determine as information.

The processor may be configured to diagnose whether the potential of the first electrode of the battery is valid based on a result of comparing the potential of the first electrode of the battery with an effective range.

The processor may be configured to output a message indicating that the state of the first electrode is bad when the potential of the first electrode of the battery is outside the valid range.

A battery pack according to another aspect of the present invention may include the device.

An electrical system according to another aspect of the present invention may include the battery pack.

A method according to another aspect of the invention is for determining the electrode information of the battery using the device. The method includes generating the Q-V curve; Converting the Q-V curve into the V-dQ / dV curve; Detecting the plurality of feature points from the V-dQ / dV curve; Classifying each of the plurality of feature points into the first electrode feature point and the second electrode feature point; And determining the type of the first electrode active material and the type of the second electrode active material included in the battery as the electrode information based on the number of the first electrode feature points and the number of the second electrode feature points. do.

The method includes obtaining a first capacitance-potential curve and a second capacitance-potential curve for a reference battery based on the type of the first electrode active material and the type of the second electrode active material; Determining a first electrode potential of the reference battery corresponding to the storage amount of each first electrode feature point from the first capacitance-potential curve; Determining the potential of the second electrode of the battery corresponding to the storage amount of each of the first electrode feature points as the electrode information based on the voltage of each of the first electrode feature points and the first electrode potential of the reference battery. step; Determining a second electrode potential of the reference battery corresponding to the capacitance of each second electrode feature point from the second capacitance-potential curve; And based on the voltage of each second electrode feature point and the second electrode potential of the reference battery, the potential of the first electrode of the battery corresponding to the storage amount of each second electrode feature point is determined as the electrode information. It may further comprise the step.

The method includes the first electrode and the second of the battery when the potential of the first electrode of the battery is outside the first effective range or when the potential of the second electrode of the battery is outside the second effective range. The method may further include outputting a message indicating that at least one of the electrodes is in a bad state.

According to the present invention, by analyzing a plurality of feature points on the V-dQ / dV curve of the battery generated based on the voltage and current of the battery, it is possible to determine the information on the positive and negative electrodes of the battery without using the reference electrode Can be.

The effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

The following drawings attached to this specification are illustrative of the preferred embodiments of the present invention, and together with the detailed description of the invention to serve to further understand the technical spirit of the present invention, the present invention is a matter described in such drawings It should not be construed as limited to.

1 is a view showing the configuration of an apparatus for determining electrode information of a battery according to an embodiment of the present invention.

2 is a graph exemplarily illustrating a Q-V curve showing a relationship between a battery voltage and a storage capacity.

3 is a graph exemplarily illustrating a V-dQ / dV curve obtained from the Q-V curve of FIG. 2.

FIG. 4 is a graph illustrating an example of smoothing of the V-dQ / dV curve of FIG. 3.

5 and 6 are graphs referenced to explain the relationship between the Q-V curve of a battery and the first capacity-potential curve and the second capacity-potential curve of a particular reference battery.

7 and 8 are flowcharts of a method for determining electrode information of a battery according to another embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the present specification and claims should not be construed as being limited to the common or dictionary meanings, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

Terms including ordinal numbers such as first and second are used for the purpose of distinguishing any one of the various components from the others, and are not used to limit the components by such terms.

Throughout the specification, when a part is said to "include" a certain component, it means that it may further include other components, without excluding the other components unless otherwise stated. In addition, the term <control unit> described in the specification means a unit for processing at least one function or operation, which may be implemented in hardware or software, or a combination of hardware and software.

In addition, throughout the specification, when a part is "connected" to another part, it is not only "directly connected" but also "indirectly connected" with another element in between. Include.

1 is a view showing the configuration of an apparatus for determining electrode information of a battery according to an embodiment of the present invention, Figure 2 is a graph showing a QV curve showing the relationship between the voltage and the storage capacity of the battery, FIG. 3 is a graph illustrating a V-dQ / dV curve obtained from the QV curve of FIG. 2. FIG. 4 is a graph illustrating a smoothed V-dQ / dV curve of FIG. 3. 5 and 6 are graphs referenced to explain the relationship between the QV curve of a battery and the first capacity-potential curve and the second capacity-potential curve of a particular reference battery.

First, referring to FIG. 1, the electrical system C may include a battery pack 1. The device 100 may be included in a battery pack 1 having a battery B including a first electrode and a second electrode. The apparatus 100 may be electrically connected to the battery B to separately estimate the first electrode potential and the second electrode potential of the battery B. The first electrode potential of the battery B may be a redox potential of the first electrode (eg, the anode) of the battery B. The second electrode potential of the battery B may be a redox potential of the second electrode (eg, the negative electrode) of the battery B.

The device 100 may be included in a battery management system (BMS) (not shown) included in the battery pack 1.

The device 100 may include a sensing unit 110, a memory unit 120, and a processor 130. The device 100 may further include a notification unit 140.

The battery B may include a plurality of unit cells electrically connected in series and / or in parallel. Of course, the case in which the battery B includes only one unit cell is also included in the scope of the present invention. The unit cell is not particularly limited as long as it can be repeatedly charged and discharged. For example, the unit cell may be a pouch type lithium polymer battery.

The battery B may be coupled to or separated from the electrical system C through a positive terminal, a negative terminal, and a communication terminal COM of the battery pack 1. The electrical system C may be, for example, an electric vehicle, a hybrid vehicle, an unmanned aerial vehicle such as a drone, an energy storage system (ESS), a charger or a mobile device electrically connected to a power grid.

The sensing unit 110 is operably coupled to the processor 130. That is, the sensing unit 110 may be configured to transmit an electrical signal to the processor 130 or to receive an electrical signal from the processor 130.

The sensing unit 110 may include a current sensor configured to measure the current of the battery B and a voltage sensor configured to measure the voltage of the battery B. The sensing unit 110 repeatedly measures the voltage applied between the positive terminal and the negative terminal of the battery B and the current flowing into or out of the battery B at predetermined intervals, and the measured voltage and the measured current. The measurement signal indicating may be output to the processor 130.

The processor 130 may convert the measurement signal received from the sensing unit 110 into a digital value representing each of the voltage and current of the battery B through signal processing, and then store the result in the memory unit 120. .

The memory unit 120 is a semiconductor memory device that records, erases, and updates data generated by the processor 130, and estimates at least one of the first electrode potential and the second electrode potential of the battery B. FIG. Stores a plurality of program codes prepared for the purpose. In addition, the memory unit 120 may store values of various predetermined parameters used when implementing the present invention.

The memory unit 120 is not particularly limited as long as it is a semiconductor memory device known to be capable of writing, erasing, and updating data. As an example, the memory unit 120 may be a DRAM, an SDRAM, a flash memory, a ROM, an EEPROM, a register, or the like. The memory unit 120 may further include a storage medium storing program codes defining control logic of the processor 130. The storage medium includes an inert storage element such as a flash memory or a hard disk. The memory unit 120 is operably coupled to the processor 130. The memory unit 120 may be physically separated from the processor 130 or may be integrally integrated with the processor 130.

The processor 130 may control the current of the battery B such that the battery B is charged or discharged with a current having a preset current value (that is, a constant current). The processor 130 may estimate the amount of power storage of the battery B for each predetermined period by integrating the current of the battery B with respect to time. The electrical storage amount of the battery B may mean an electrical charge stored in the battery B.

In this case, a preset current value (that is, the magnitude of the constant current) may be calculated by the processor 130 using Equation 1 below.

<Equation 1>

I _c = a × C _n

Here, I _c is the magnitude of the constant current, a is a constant of 1 or less (eg, 0.6), and C _n may be the magnitude of the rated current of the battery B.

The processor 130 may estimate the amount of power storage of the battery B for each predetermined period, based on a period during which the battery B is charged or discharged with a current having a preset current value. For example, the processor 130 may repeatedly calculate the amount of power storage of the battery B at a predetermined cycle by using the current integration method. Of course, the method of calculating the electrical storage amount of the battery B is not limited to the current integration method alone.

The processor 130 may generate a voltage-capacitance curve of the battery B based on a result of mapping the capacitance of the battery B and the voltage of the battery B obtained at predetermined cycles.

Here, the voltage of the battery B may be an open circuit voltage (OCV) of the battery B.

The voltage-capacitance curve of the battery B (hereinafter, may be referred to as a 'VQ curve' or a 'QV curve') is a storage amount Q and a voltage V of the battery B, as shown in FIG. 2. It can be represented in a format that defines the relationship between them.

The V-Q curve may be stored in the memory unit 120 in the form of a function of approximating a capacitance of the battery B according to the voltage of the battery B to a curve. Alternatively, the V-Q curve may be stored in the memory unit 120 in the form of a lookup table.

The processor 130 converts the V-Q curve (or a function corresponding to the V-Q curve) of the battery B into a V-dQ / dV curve. dQ / dV represents the ratio of the change amount dQ of the storage amount of the battery B to the change amount dV of the voltage of the battery B. That is, the processor 130 may generate V-dQ / dV illustrated in FIG. 3 by differentiating a V-Q curve (or a function corresponding to the V-Q curve) with respect to the voltage V of the battery B. FIG. V-dQ / dV is a curve showing the relationship between the voltage V of the battery B and dQ / dV.

Next, the processor 130 may detect a plurality of feature points (eg, a maximum point, a minimum point, and an inflection point) on the V-dQ / dV curve. Each feature point detected from the V-dQ / dV curve may correspond to a specific order individually among all the feature points appearing in the V-dQ / dV curve. For example, when the processor 130 is set to detect three feature points from the V-dQ / dV curve, the three feature points correspond to l on the V-dQ / dV curve in order of decreasing storage capacity of each of the three feature points. It may be the first local maximum, the m maximum local maximum, the nth local minimum.

The processor 130 may remove a noise component of the V-dQ / dV curve of FIG. 3 using a noise filter before detecting a plurality of feature points on the V-dQ / dV curve. As a result, the V-dQ / dV curve of FIG. 3 can be flattened as shown in FIG. 4. Through this, it is possible to improve the accuracy of the feature point detection by preventing the phenomenon that the feature point is incorrectly detected from the V-dQ / dV curve of Figure 3 due to the noise component present in the V-dQ / dV of FIG. Of course, planarization of the V-dQ / dV curve of FIG. 3 is an optional process, and the processor 130 may use a plurality of feature points from the V-dQ / dV curve of FIG. 3 instead of the V-dQ / dV curve of FIG. 4. May be detected. Hereinafter, for convenience of description, it is assumed that a plurality of feature points are detected from the V-dQ / dV curve of FIG. 4. Specifically, the processor 130 is a V-dQ / dV curve at each point on the V-dQ / dV curve that the two derivatives of the VQ curve (or a function corresponding to the VQ curve) of the battery B is 0 It can detect by the characteristic point of.

As an example, the processor 130 may mark each point on the V-dQ / dV curve in which the ratio of the change amount dQ of the storage capacity of the battery B to the change amount dV of the voltage of the battery B increases and decreases. (Maximum point) can be detected.

As another example, the processor 130 may determine each point on the V-dQ / dV curve in which the ratio of the change amount dQ of the storage capacity of the battery B to the change amount dV of the voltage of the battery B decreases and increases. Minimum point).

Each feature point may be represented by a pair of the voltage V of the battery B and the storage amount Q (or dQ / dV) at the voltage V.

4 shows, by the processor 130, eight feature points I _A1 , I _A2 , I _A3 , I _A4 , I _A5 , I _A6 , I _C1 , I _C2 located on the V-dQ / dV curve. This detected example is shown.

The processor 130 based on a result of comparing the voltage of each feature point with a predetermined reference voltage, the feature points I _A1 , I _A2 , I _A3 , I _A4 , I _A5 , I _A6 , I _C1 , I _C2 Each may be classified into any one of the first electrode feature point and the second electrode feature point.

Specifically, the processor 130, when the voltage of a particular feature of the feature points (I _A1 , I _A2 , I _A3 , I _A4 , I _A5 , I _A6 , I _C1 , I _C2 ) is greater than or equal to a predetermined reference voltage, Specific feature points may be classified as first electrode feature points. In contrast, when the voltage of a specific feature point is less than a predetermined reference voltage, the processor 130 may classify the specific feature point as the second electrode feature point instead of the first electrode feature point.

The first electrode feature point may be a feature point detected by an electrochemical characteristic of an active material (hereinafter, referred to as a “first electrode active material”) used to manufacture the first electrode of the battery B. Even if the battery B deteriorates, the first electrode potential of the battery B at the storage amount of each of the first electrode feature points may be constant.

The second electrode feature point may be a feature point detected by an electrochemical characteristic of an active material (hereinafter, referred to as a “second electrode active material”) used to manufacture the second electrode of the battery B. Even if the battery B deteriorates, the second electrode potential of the battery B at the storage amount of each of the second electrode feature points may be constant.

Suppose that the predetermined reference voltage is 3.8 Volt. Then, the processor 130, the feature point (I _A1 , I _A2 , I _A3 , I _A4 , I _A5 , I _A6 , I _C1 , I _C2 ) of the feature points (I) located in a voltage range of a predetermined reference voltage or more _C1 , I _C2 ) may be classified as first electrode feature points. The processor 130 includes a feature point (I _A1, I _A2, I _A3, I _A4, I _A5, I _A6, I _C1, I _C2) from, a feature point which is located in the voltage range less than a predetermined reference voltage (I _A1 , I _A2 , I _A3 , I _A4 , I _A5 , I _A6 ) may be classified as second electrode feature points.

The processor 130 is a type of the first electrode active material included in the battery B based on the feature points I _A1 , I _A2 , I _A3 , I _A4 , I _A5 , I _A6 , I _C1 , and I _C2 . And the type of the second electrode active material. Specifically, the processor 130 may identify the type of the first electrode active material and the type of the second electrode active material of the battery B based on the number of first electrode feature points and the number of second electrode feature points.

To this end, the memory unit 120 includes a lookup table ('active material list table') in which the number of first electrode feature points, the number of second electrode feature points, the type of the first electrode active material, and the type of the second electrode active material are mapped. May be stored in advance).

As described above, when the number of first electrode feature points is two and the number of second electrode feature points is six, the processor 130 may determine the number of first electrode feature points and the number of second electrode feature points, respectively. Using the index and the second index, each of "LiMO ₂ " and "SiO ₂ " can be obtained from the active material list table as the kind of the first electrode active material and the kind of the second electrode active material contained in the battery B. Of course, when the number of first electrode feature points is not two or the number of second electrode feature points is not six, another kind of active material is obtained as the first electrode active material of the battery B instead of “LiMO ₂ ”, or “ Instead of SiO ₂ ″, another kind of active material may be obtained as the second electrode active material of the battery B.

The memory unit 120 may store at least one of the first capacitance-potential curve and the second capacitance-potential curve for each of the plurality of reference batteries in the form of a lookup table. Each reference battery is distinguished from other reference batteries based on the type of the positive electrode active material and the type of the negative electrode active material contained therein. That is, each reference battery may include a cathode active material different from the cathode active material included in the remaining reference batteries, or may include a cathode active material different from the anode active material included in the remaining reference batteries.

The processor 130 may include a first battery of a reference battery (hereinafter, referred to as a specific reference battery) having the same type as the battery B, the first electrode active material, and the second electrode active material. A capacitance-potential curve and a second capacitance-potential curve may be obtained from the memory unit 120.

5 and 6, together with the QV curve D _B of the battery B, the first capacity-potential curve D _R1 and the second capacity-potential curve D _R2 for the specific reference battery are combined together. Is shown. The QV curve D _B may be illustrated by using the vertical axis and the horizontal axis of the VQ curve illustrated in FIG. 2 as the horizontal axis and the vertical axis, respectively.

The first capacitance-potential curve D _R1 for the specific reference battery represents the relationship between the first electrode potential and the storage amount of the specific reference battery that is before deterioration (eg, BOL: Beginning Of Life). The first electrode potential of the specific reference battery may mean a redox potential of the first electrode (eg, an anode) of the specific reference battery.

The second capacitance-potential curve D _{R2 for the} specific reference battery indicates the relationship between the second electrode potential and the storage amount of the specific reference battery before deterioration. The second electrode potential of the specific reference battery may mean a redox potential of the second electrode (eg, negative electrode) of the specific reference battery.

The processor 130 may include a first electrode potential of the specific reference battery corresponding to a storage amount of each of the feature points I _A1 , I _A2 , I _A3 , I _A4 , I _A5 , I _A6 , I _C1 , and I _C2 , or The second electrode potential can be read out.

As illustrated in FIG. 5, the processor 130 may read the capacitance and the voltage of each of the first electrode feature points I _C1 and I _C2 of FIG. 4 from the QV curve D _B.

Then, the processor 130 is configured to determine the first electrode feature points I _C1 and I _C2 corresponding to the respective stored capacitances from the first electrode potential of the specific reference battery corresponding to the respective stored capacitances. The voltage may be subtracted to determine the second electrode potential of the battery B corresponding to each of the read amounts of power storage. The processor 130 may calculate the second electrode potential of the battery B corresponding to the storage amount Q by using Equation 2 below.

<Equation 2>

V _R2 (Q) = V _R1 (Q) V _B1 (Q)

Here, V _R1 (Q) is the first electrode potential ('■' in FIG. 5) of the specific reference battery corresponding to the storage amount Q, and V _B1 (Q) is the voltage of the first electrode feature point corresponding to the storage amount Q. ('' In FIG. 5) and V _R2 (Q) are the second electrode potentials ('' in FIG. 5) of the battery B corresponding to the storage amount Q.

The processor 130 determines V _R2 (Q) as the negative electrode potential of the battery B corresponding to the storage amount Q, and V _R1 (Q) to the positive potential of the battery B corresponding to the storage amount Q. You can decide.

Meanwhile, as illustrated in FIG. 6, the processor 130 may include a second electrode feature point I among feature points I _A1 , I _A2 , I _A3 , I _A4 , I _A5 , I _A6 , I _C1 , and I _C2 . _A1 , I _A2 , I _A3 , I _A4 , I _A5 , and I _A6 ) can be read from the QV curve D _B of the battery B, respectively.

The processor 130 may further include a second electrode potential of the specific reference battery corresponding to each of the read amounts of electricity stored and second electrode feature points I _A1 , I _A2 , I _A3 , and I corresponding to the read amounts of stored electricity. The voltages of _A4 , I _A5 and I _A6 may be summed to determine the first electrode potential of the battery B corresponding to each of the read amounts of electricity stored. The processor 130 may calculate the first electrode potential of the battery B corresponding to the storage amount Q by using Equation 3 below.

<Equation 3>

V _Q1 (Q) = V _Q2 (Q) + V _B2 (Q)

Here, V _Q2 (Q) is the second electrode potential ('' of FIG. 6) of the specific reference battery corresponding to the storage amount Q, and V _B2 (Q) is the voltage of the second electrode feature point corresponding to the storage amount Q. ('' In FIG. 6) and V _Q1 (Q) are the first electrode potentials ('' in FIG. 6) of the battery B corresponding to the electric storage amount Q.

The processor 130 determines V _Q1 (Q) as the anode potential of the battery B corresponding to the storage amount Q, and V _Q2 (Q) to the cathode potential of the battery B corresponding to the storage amount Q. You can decide.

As described above with reference to FIGS. 5 and 6, by measuring the voltage and current of the battery B, each of the positive and negative potentials of the battery B can be accurately estimated without using the reference electrode.

On the other hand, the processor 130 compares the electrode potential (ie, the first electrode potential or the second electrode potential) of the battery B with the effective range, and the electrode potential of the battery B is effective based on the comparison result. Can diagnose whether or not.

The processor 130 may determine that the electrode potential of the battery B is invalid if the electrode potential of the battery B is not included in the effective range. An invalid electrode potential of the battery B may indicate that at least one of the first electrode and the second electrode of the battery B deteriorates by a certain level or more, so that the battery B needs to be replaced with a new one. have.

The processor 130 may set an effective range with reference to the first capacitance-potential curve D _R1 and the second capacitance-potential curve D _R2 of the specific reference battery.

Specifically, the processor 130 may determine the first electrode potential of the specific reference battery corresponding to the storage amount of each of the second electrode feature points I _A1 , I _A2 , I _A3 , I _A4 , I _A5 , and I _A6 . It can be read from the first dose-potential curve D _R1 . Thereafter, the processor 130 may set a first effective range (eg, 3.9 to 4.2 Volt) based on the read first electrode potential of the specific reference battery. The processor 130 may diagnose whether the first electrode potential of the battery B is valid by comparing the first effective range with the first electrode potential of the battery B. FIG. For example, when the first electrode potential of the battery B is out of the first effective range, it may be diagnosed that the state of the first electrode of the battery B is poor.

The processor 130 may read the second electrode potential of the specific reference battery corresponding to the capacitance of each of the first electrode feature points I _C1 and I _C2 from the second capacitance-potential curve D _R2 . . Thereafter, the processor 130 may set a second effective range (for example, 0.03 to 0.2 Volt) based on the second electrode potential of the specific reference battery. The processor 130 may diagnose whether the second electrode potential of the battery B is valid by comparing the second valid range with the second electrode potential of the battery B. FIG. For example, when the second electrode potential of the battery B is out of the second effective range, it may be diagnosed that the state of the second electrode of the battery B is poor.

Alternatively, the first validity range and the second validity range may be preset.

The processor 130 may transmit a message indicating the electrode information of the battery B to the electrical system C through the communication terminal COM. The notification unit 140 may be operatively coupled to the processor 130. The notification unit 140, in response to receiving the message from the processor 130, a display unit for visually displaying (eg, symbols, numbers, images) of the electrode information of the battery (B) and acoustically It may include at least one of the speaker device for outputting.

The processor 130 may optionally include application-specific integrated circuits (ASICs), other chipsets, logic circuits, registers, communication modems, data processing devices, and the like, which are known in the art to execute various control logics. At least one of various control logics that may be executed by the processor 130 may be combined, and the combined control logics may be written in a computer readable code system and stored in a computer readable recording medium. The recording medium is not particularly limited as long as it is accessible by the processor 130 included in the computer. In one example, the recording medium includes at least one selected from the group consisting of a ROM, a RAM, a register, a CD-ROM, a magnetic tape, a hard disk, a floppy disk, and an optical data recording device. In addition, the code scheme may be modulated into a carrier signal to be included in a communication carrier at a particular point in time, and distributed and stored and executed in a networked computer. In addition, functional programs, code and code segments for implementing the combined control logics can be easily inferred by programmers in the art to which the present invention pertains.

7 and 8 are flowcharts of a method for determining electrode information of a battery according to another embodiment of the present invention.

1 to 8, in step S700, the processor 130 determines the voltage V and the storage amount Q of the battery B based on the measurement signal from the sensing unit 110. Data representing V and Q determined in operation S700 may be stored in the memory unit 120 at predetermined intervals.

In step S710, the processor 130 determines whether or not a power storage amount corresponding to a predetermined voltage range (eg, discharge end voltage to charge end voltage) is determined. If the value of step S710 is YES, step S720 may proceed. If the value of step S710 is "no", step S700 may be resumed.

In step S720, the processor 130 generates a Q-V curve (see FIG. 2, etc.) indicating a relationship between the voltage of the battery B and the storage amount.

In operation S730, the processor 130 converts the Q-V curve for the battery B into a V-dQ / dV curve (see FIG. 4, etc.).

In operation S740, the processor 130 detects a plurality of feature points from the V-dQ / dV curve.

In operation S750, the processor 130 classifies each of the plurality of feature points into a first electrode feature point and a second electrode feature point.

In operation S760, the processor 130 may determine the type of the first electrode active material and the type of the second electrode active material included in the battery B based on the number of first electrode feature points and the number of second electrode feature points. Decide as After step S760, the method may end or proceed to step S800.

In operation S800, the processor 130 obtains a first capacity-potential curve and a second capacity-potential curve for the reference battery from the memory unit 120. The reference battery has the same kind of first electrode active material and the same kind of second electrode active material as the battery B.

In step S810, the processor 130 determines the first electrode potential of the reference battery corresponding to the storage amount of each first electrode feature point from the first capacitance-potential curve.

In operation S820, the processor 130 may determine the second electrode potential of the battery B corresponding to the storage amount of each first electrode feature point based on the voltage of each first electrode feature point and the first electrode potential of the reference battery. Determined as electrode information.

In operation S830, the processor 130 determines a second electrode potential of the reference battery corresponding to the storage amount of each second electrode feature point from the second capacitance-potential curve.

In operation S840, the processor 130 may determine the first electrode potential of the battery B corresponding to the storage amount of each second electrode feature point based on the voltage of each second electrode feature point and the second electrode potential of the reference battery. Determined as electrode information.

In step S850, the processor 130 determines whether the first electrode potential of the battery B is within the first valid range and whether the second electrode potential of the battery B is within the second valid range. If the value of step S850 is YES, step S860 may proceed. If the value of step S850 is "no", step S870 may proceed.

In operation S860, the processor 130 outputs a first message. The first message may indicate that the first and second electrodes of the battery B are in good condition.

In operation S870, the processor 130 outputs a second message. The second message may indicate that at least one of the first electrode and the second electrode of the battery B is in a bad state.

The embodiments of the present invention described above are not implemented only through the apparatus and the method, but may be implemented through a program for realizing a function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded. Implementation may be easily implemented by those skilled in the art from the description of the above-described embodiments.

Although the present invention has been described above by means of limited embodiments and drawings, the present invention is not limited thereto and will be described below by the person skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of the claims.

In addition, the present invention described above is capable of various substitutions, modifications, and changes within the scope without departing from the spirit of the present invention for those of ordinary skill in the art to which the present invention pertains to the above-described embodiments and attached Not limited by the drawings, all or part of the embodiments may be selectively combined to enable various modifications.

<Description of the code>

C: electrical system

1: battery pack

B: battery

100: device

110: sensing unit

120: memory

130: processor

140: alarm unit

Claims (13)

1. An apparatus for determining electrode information of a battery comprising a first electrode and a second electrode,

   A sensing unit configured to measure a voltage of the battery and a current of the battery; And

   A processor operatively coupled with the sensing unit,

   The processor,

   On the basis of the current of the battery, determining the amount of power storage of the battery,

   Converts a QV curve representing the relationship between the voltage of the battery and the storage capacity of the battery to a V-dQ / dV curve representing the relationship between the voltage of the battery and the change ratio of the storage amount to the variation of the voltage of the battery; ,

   Detecting a plurality of feature points from the V-dQ / dV curve,

   Each of the plurality of feature points is classified into a first electrode feature point and a second electrode feature point,

   And determine the type of the first electrode active material and the type of the second electrode active material included in the battery as the electrode information based on the number of the first electrode feature points and the number of the second electrode feature points.
2. The method of claim 1,

   The processor,

   Among the plurality of feature points, each feature point positioned in a voltage range equal to or greater than a predetermined reference voltage is classified as the first electrode feature point,

   And, among the plurality of feature points, classify each feature point located in a voltage range below the reference voltage as the second electrode feature point.
3. The method of claim 1,

   The processor,

   Obtain a first capacity-potential curve of a reference battery from a memory portion operably coupled to the processor,

   Determining a first electrode potential of the reference battery corresponding to the capacitance of each of the first electrode feature points from the first capacitance-potential curve,

   Determine, as the electrode information, the potential of the second electrode of the battery corresponding to the capacitance of each of the first electrode feature points based on the voltage of each of the first electrode feature points and the first electrode potential of the reference battery. Composed,

   And the reference battery includes the first electrode active material and the second electrode active material.
4. The method of claim 3,

   The processor,

   Subtract the voltage of each of the first electrode feature points from the first electrode potential of the reference battery to determine the potential of the second electrode of the battery corresponding to the storage amount of each of the first electrode feature points as the electrode information. Configured device.
5. The method of claim 3,

   The processor,

   Obtaining a second capacitance-potential curve of the reference battery from the memory unit,

   A second electrode potential of the reference battery corresponding to the storage amount of each second electrode feature point is determined from the second capacitance-potential curve,

   Determine, as the electrode information, the potential of the first electrode of the battery corresponding to the capacitance of each of the second electrode feature points based on the voltage of each second electrode feature point and the second electrode potential of the reference battery. Configured device.
6. The method of claim 5,

   The processor,

   Summing the voltage of each of the second electrode feature points and the second electrode potential of the reference battery to determine the potential of the first electrode of the battery corresponding to the storage amount of each of the second electrode feature points as the electrode information. Configured device.
7. The method of claim 5,

   The processor,

   And determine whether the potential of the first electrode of the battery is valid based on a result of comparing the potential of the first electrode of the battery with an effective range.
8. The method of claim 7, wherein

   The processor,

   And output a message indicating that the state of the first electrode of the battery is bad when the potential of the first electrode of the battery is outside the first valid range.
9. A battery pack comprising the device according to claim 1.
10. An electrical system comprising the battery pack according to claim 9.
11. A method for determining the electrode information of the battery, using the apparatus according to any one of claims 1 to 8,

    Generating the Q-V curve;

    Converting the Q-V curve into the V-dQ / dV curve;

    Detecting the plurality of feature points from the V-dQ / dV curve;

    Classifying each of the plurality of feature points into the first electrode feature point and the second electrode feature point; And

    Determining the type of the first electrode active material and the type of the second electrode active material included in the battery as the electrode information based on the number of the first electrode feature points and the number of the second electrode feature points. , Way.
12. The method of claim 11,

    Obtaining a first capacitance-potential curve and a second capacitance-potential curve for a reference battery based on the kind of the first electrode active material and the kind of the second electrode active material;

    Determining a first electrode potential of the reference battery corresponding to the storage amount of each first electrode feature point from the first capacitance-potential curve;

    Determining the potential of the second electrode of the battery corresponding to the storage amount of each of the first electrode feature points as the electrode information based on the voltage of each of the first electrode feature points and the first electrode potential of the reference battery. step;

    Determining a second electrode potential of the reference battery corresponding to the capacitance of each second electrode feature point from the second capacitance-potential curve; And

    Determining the potential of the first electrode of the battery corresponding to the storage amount of each of the second electrode feature points as the electrode information based on the voltage of each of the second electrode feature points and the second electrode potential of the reference battery. Further comprising a step.
13. The method of claim 12,

    At least one of the first electrode and the second electrode of the battery when the potential of the first electrode of the battery is outside the first effective range or when the potential of the second electrode of the battery is outside the second effective range And outputting a message indicating that the state of is bad.

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