Patent ID: 12248024

DETAILED DESCRIPTION

It should be understood that the terms used in the specification and the appended claims should not be construed as limited to general and dictionary meanings, but interpreted based on the meanings and concepts corresponding to technical aspects of the present disclosure on the basis of the principle that the inventor is allowed to define terms appropriately for the best explanation.

Therefore, the description proposed herein is just a preferable example for the purpose of illustrations only, not intended to limit the scope of the disclosure, so it should be understood that other equivalents and modifications could be made thereto without departing from the scope of the disclosure.

Additionally, in describing the present disclosure, when it is deemed that a detailed description of relevant known elements or functions renders the key subject matter of the present disclosure ambiguous, the detailed description is omitted herein.

The terms including the ordinal number such as “first”, “second” and the like, may be used to distinguish one element from another among various elements, but not intended to limit the elements by the terms.

Throughout the specification, when a portion is referred to as “comprising” or “including” any element, it means that the portion may include other elements further, without excluding other elements, unless specifically stated otherwise.

In addition, throughout the specification, when a portion is referred to as being “connected” to another portion, it is not limited to the case that they are “directly connected”, but it also includes the case where they are “indirectly connected” with another element being interposed between them.

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

FIG.1is a diagram schematically showing a battery classification apparatus100according to an embodiment of the present disclosure.

Referring toFIG.1, the battery classification apparatus100according to an embodiment of the present disclosure may include a profile generating unit110and a control unit120.

The profile generating unit110may be configured to obtain battery information about capacity and voltage of a battery.

Here, the battery means one physically separable independent cell including a negative electrode terminal and a positive electrode terminal. For example, one lithium-ion battery or lithium polymer battery may be regarded as a battery.

For example, the profile generating unit110may obtain a battery profile representing a corresponding relationship between a capacity and a voltage of the battery. That is, the battery profile may include battery information in which the capacity and the voltage of the battery are mapped.

The profile generating unit110may be configured to generate a differential profile representing a corresponding relationship between a differential voltage based on capacity and voltage and the capacity.

Here, the differential voltage is a value obtained by differentiating the voltage included in the battery information by the capacity, and may be expressed as “dV/dQ”. That is, the differential voltage may be a value representing an instantaneous change rate of voltage with respect to capacity. The differential profile will be described with reference to the embodiment ofFIG.2.

FIG.2is a diagram schematically showing a first differential profile DP1according to an embodiment of the present disclosure.

Specifically, the first differential profile DP1is a differential profile for a battery containing an NMCO positive electrode material having a nickel content of 80% and a 100% graphite-based negative electrode material. In addition, the first differential profile DP1is a differential profile generated based on the voltage and capacity of the battery obtained when the battery is charged at a temperature of 25° C. and at a 0.05 C-rate.

In the embodiment ofFIG.2, the profile generating unit110may generate the first differential profile DP1representing a corresponding relationship between the capacity and the differential voltage, based on the obtained battery information. Specifically, in the first differential profile DP1, the capacity of the battery may be normalized to have a capacity region of 0 to 1. For this reason, when the plurality of batteries are classified, the capacity regions for the plurality of batteries are normalized, so that the plurality of batteries may be classified under the same condition.

The control unit120may be configured to obtain a differential profile from the profile generating unit110.

For example, the control unit120and the profile generating unit110may be connected to communicate with each other. The profile generating unit110may transmit the generated first differential profile DP1to the control unit120, and the control unit120may receive the first differential profile DP1from the profile generating unit110.

The control unit120may be configured to detect a plurality of peaks in the obtained differential profile.

Here, the peak may be a point having an upward convex form in the differential profile. That is, the peak is a point at which the change rate of the differential voltage with respect to capacity is 0. Based on the peak, the change rate may be positive at a low capacity side, and the change rate may be negative at a high capacity side.

For example, in the first differential profile DP1according to the embodiment ofFIG.2, the control unit120may detect a first peak P1, a second peak P2, a third peak P3, and a fourth peak P4.

The control unit120may be configured to classify the battery into any one of a plurality of preset groups based on a plurality of classification conditions preset for the number of the plurality of detected peaks and the differential voltage.

Specifically, the plurality of classification conditions may include a first classification condition and a second classification condition. For example, the first classification condition may be a classification condition about whether a peak at which a corresponding differential voltage is greater than or equal to a criterion value R exists in a first capacity region RR1. In addition, the second classification condition may be a classification condition about whether a peak at which a corresponding differential voltage is greater than or equal to the criterion value R exists in a second capacity region RR2.

For example, in the embodiment ofFIG.2, the first peak P1and the second peak P2may be included in the first capacity region RR1, and the third peak P3and the fourth peak P4may be included in the second capacity region RR2. Since the differential voltage dl of the first peak P1and the differential voltage d2of the second peak P2are equal to or greater than the criterion value R, the battery may satisfy the first classification condition. In addition, since the differential voltage d3of the third peak P3and the differential voltage d4of the fourth peak P4are also equal to or greater than the criterion value R, the battery may satisfy the second classification condition.

The control unit120may be configured to classify the battery into a first group, when the battery satisfies both the first classification condition and the second classification condition. Conversely, if the battery does not satisfy at least one of the first classification condition and the second classification condition, the control unit120may be configured to classify the battery into a second group.

For example, in the embodiment ofFIG.2, since the battery satisfies both the first classification condition and the second classification condition, it may be classified into the first group.

More specifically, the control unit120may be configured to determine the battery classified into the first group as a BOL (Beginning of Life) battery or a MOL (Middle of Life) battery containing a graphite-based negative electrode material. In addition, the control unit120may be configured to determine the battery classified into the second group as a battery containing a non-graphite-based negative electrode material or an EOL (End of Life) battery containing a graphite-based negative electrode material.

That is, the control unit120may be configured to determine the battery classified into the first group as a reusable battery. Also, the control unit120may be configured to determine the battery classified into the second group as a non-reusable battery.

For example, in the embodiment ofFIG.2, the battery classified into the first group may be regarded as a BOL battery or a MOL battery and thus classified as a reusable battery.

In general, a battery containing 100% graphite-based negative electrode material is known to have a relatively long charging/discharging lifespan, compared to a battery containing graphite and a non-graphite-based negative electrode material or a battery containing 100% non-graphite-based negative electrode material. That is, the battery including 100% graphite-based negative electrode material may exhibit high performance efficiency due to a relatively long lifespan even if it is reused.

Therefore, the battery classification apparatus100has an advantage of classifying a battery in a non-destructive way according to the type of negative electrode material and the state of the battery. Furthermore, the battery classification apparatus100has an advantage of more specifically classifying the battery into a reusable battery or a non-reusable battery.

For example, a battery installed in an electric vehicle deteriorates its performance when it is driven for about 200,000 km or more, and it is classified as a waste battery and needs to be replaced. However, since such a waste battery has a high energy density, it is sufficiently applicable to other fields. In other words, the waste battery simply cannot show its maximum performance just when applied to an electric vehicle, and if it is used in secondary and tertiary applications such as ESS (Energy storage system) that is not frequently charged and discharged and requires high energy density compared to electric vehicles, it can be reused for the remainder of its lifespan. In addition, if the waste battery is disposed of without being reused secondly or tertiarily, it may adversely affect the environment in terms of pollution.

Therefore, since a reusable battery can be classified in a non-destructive way by the battery classification apparatus100according to an embodiment of the present disclosure, the production cost of the battery may be reduced according to the reuse and recycling of the waste battery, and there is a great advantage in that the environmental contamination can be minimized.

Meanwhile, the control unit120provided in the battery classification apparatus100may selectively include processors known in the art, application-specific integrated circuit (ASIC), other chipsets, logic circuits, registers, communication modems, data processing devices, and the like to execute various control logic performed in the present disclosure. Also, when the control logic is implemented in software, the control unit120may be implemented as a set of program modules. At this time, the program module may be stored in a memory and executed by the control unit120. The memory may be located inside or out of the control unit120and may be connected to the control unit120by various well-known means.

In addition, the battery classification apparatus100may further include a storage unit130. The storage unit130may store data necessary for operation and function of each component of the battery classification apparatus100, data generated in the process of performing the operation or function, or the like. The storage unit130is not particularly limited in its kind as long as it is a known information storage means that can record, erase, update and read data. As an example, the information storage means may include random access memory (RAM), flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), registers, and the like. In addition, the storage unit130may store program codes in which processes executable by the control unit120are defined.

For example, the storage unit130may store the battery information representing a corresponding relationship between voltage and capacity of the battery. Also, the storage unit130may store the BOL battery information representing a corresponding relationship between voltage and capacity of the BOL battery. In addition, the profile generating unit110may access the storage unit130to obtain battery information, and generate a differential profile for the battery based on the obtained battery information.

In addition, the storage unit130may store the differential profile generated by the profile generating unit110. The control unit120may directly receive the differential profile from the profile generating unit110, and may access the storage unit130to obtain the stored differential profile. Also, the control unit120may access the storage unit130to obtain the battery information and the BOL battery information.

Hereinafter, an embodiment in which the control unit120divides the capacity region of the differential profile into a first capacity region RR1and a second capacity region RR2will be described.

The control unit120may be configured to set the first capacity region RR1and the second capacity region RR2based on a capacity at which a corresponding differential voltage is lowest in a predetermined capacity region RQ of the differential profile.

For example, in the embodiment ofFIG.2, the predetermined capacity region RQ may be preset to 0.3 to 0.5. In addition, the control unit120may set the first capacity region RR1and the second capacity region RR2based on the capacity corresponding to the lowest differential voltage in the predetermined capacity region RQ. That is, the control unit120may set a low capacity region and a high capacity region based on the capacity corresponding to the lowest differential voltage in the predetermined capacity region RQ.

Due to the characteristics of a battery containing a positive electrode material and a negative electrode material, the differential voltage in the low capacity region is relatively strongly affected by the negative electrode, and the differential voltage in the high capacity region is relatively strongly affected by the positive electrode. This is the same not only for the differential voltage, but also for the differential capacity that can be expressed as “dQ/dV”.

The control unit120may judge whether the battery satisfies the first classification criterion based on the differential voltage of a plurality of peaks in the first capacity region RR1, which is relatively strongly affected by the negative electrode. Also, the control unit120may judge whether the battery satisfies the second classification criterion based on the differential voltage of a plurality of peaks in the second capacity region RR2, which is relatively strongly affected by the positive electrode. That is, the control unit120may improve the accuracy and reliability of battery classification by judging whether the battery satisfies the first classification criterion and the second classification criterion, respectively, in consideration of the characteristics of the battery according to the capacity region.

Hereinafter, an embodiment in which the control unit120sets the criterion value R serving as a criterion for judging whether the first classification criterion is satisfied and whether the second classification criterion is satisfied will be described.

The control unit120may be configured to select a peak at which the corresponding differential voltage is greatest among the plurality of peaks as a target peak.

Here, the control unit120may select the target peak in the entire capacity region of the battery, unlike the embodiment in which the first capacity region RR1and the second capacity region RR2are set. For example, in the embodiment ofFIG.2, the third peak P3having the greatest differential voltage may be determined as the target peak TP1.

The control unit120may be configured to determine a first differential voltage R1based on the differential voltage of the selected target peak.

Specifically, the control unit120may be configured to determine a value smaller than the differential voltage of the target peak by a first reference value r1as the first differential voltage R1.

For example, in the embodiment ofFIG.2, the differential voltage of the target peak TP1may be d3. The control unit120may determine a value smaller than the differential voltage d3of the target peak TP1by the first reference value r1as the first differential voltage R1.

The control unit120may be configured to determine a second differential voltage R2based on the lowest differential voltage L of the differential profile.

Specifically, the control unit120may be configured to determine a value greater than the lowest differential voltage L by a second reference value r2as the second differential voltage R2.

For example, in the embodiment ofFIG.2, the lowest differential voltage L of the differential profile may be L. The control unit120may determine a value greater than the lowest differential voltage L by the second reference value r2as the second differential voltage R2.

The control unit120may be configured to set a greater value of the first differential voltage R1and the second differential voltage R2as the criterion value R.

For example, in the embodiment ofFIG.2, since the first differential voltage R1is greater than the second differential voltage R2, the first differential voltage R1may be set as the criterion value R.

In general, since the non-graphite-based negative electrode active material that can be contained in the negative electrode material of the battery exhibits capacity in the low capacity region, it may have greater hysteresis for resistance and OCV (Open Circuit Voltage) and low charging/discharging efficiency, compared to graphite. For example, silicon (ex. SiO) may be applied to the non-graphite-based negative electrode active material. According to the characteristics of the non-graphite-based negative electrode active material, a battery containing a non-graphite-based negative electrode material has a lower differential voltage in the low capacity region compared to a battery containing a graphite-based negative electrode material. Therefore, the control unit120may classify the battery more accurately by setting the criterion value R based on the greater value of the first differential voltage R1and the second differential voltage R2.

Hereinafter, an embodiment for each of the plurality of differential profiles generated by the profile generating unit110will be described.

FIG.3is a diagram schematically showing a second differential profile DP2according to an embodiment of the present disclosure.

Specifically, the second differential profile DP2is a differential profile for a battery containing an NMCO positive electrode material with a nickel content of 80% and a 100% non-graphite-based negative electrode material (SiO). In addition, the second differential profile DP2is a differential profile generated based on the voltage and capacity of the battery obtained when the battery is charged at a temperature of 25° C. and at a 0.05 C-rate.

The control unit120may detect the fourth peak P4, the fifth peak P5, and the sixth peak P6in the second differential profile DP2. In addition, the control unit120may determine the sixth peak P6having the greatest differential voltage among the fourth peak P4, the fifth peak P5, and the sixth peak P6as the target peak TP2.

The control unit120may determine a value smaller than the differential voltage d6of the target peak TP2by the first reference value r1as the first differential voltage RE Also, the control unit120may determine a value greater than the lowest differential voltage L of the second differential profile DP2by the second reference value r2as the second differential voltage R2. Here, since the first differential voltage R1is greater than the second differential voltage R2, the control unit120may set the first differential voltage R1as the criterion value R.

Since the differential voltage d4of the fourth peak P4included in the first capacity region RR1is smaller than the criterion value R, the control unit120may judge that the battery does not satisfy the first classification criterion.

In order for the battery to be classified into the first group, both the first classification criterion and the second classification criterion must be satisfied, so the control unit120may classify the battery into the second group without judging whether the battery satisfies the second classification criterion.

Preferably, since the control unit120may classify the battery according to the type of negative electrode material contained in the battery, it is possible to judge whether the battery satisfies the first classification criterion first, and then judge whether the battery satisfies the second classification criterion. This is because the differential voltage in the first capacity region RR1, which is a low capacity region, is more affected by the negative electrode than the positive electrode as described above.

In addition, the control unit120may classify that the battery is a battery containing a non-graphite-based negative electrode material or an EOL battery containing a graphite-based negative electrode material, and is a non-reusable battery.

FIG.4is a diagram schematically showing a third differential profile DP3according to an embodiment of the present disclosure.

Specifically, the third differential profile DP3is a differential profile for a battery containing an LMO (lithium manganese oxide) positive electrode material and a 100% graphite-based negative electrode material. In addition, the third differential profile DP3is a differential profile generated based on the voltage and capacity of the battery obtained when the battery is charged at a temperature of 25° C. and at a 0.05 C-rate.

The control unit120may detect the seventh peak P7, the eighth peak P8and the ninth peak P9in the third differential profile DP3. In addition, the control unit120may determine the seventh peak P7having the greatest differential voltage among the seventh peak P7, the eighth peak P8, and the ninth peak P9as the target peak TP3.

The control unit120may determine a value smaller than the differential voltage d7of the target peak TP3by the first reference value r1as the first differential voltage R1. Also, the control unit120may determine a value greater than the lowest differential voltage L of the third differential profile DP3by the second reference value r2as the second differential voltage R2. Here, since the first differential voltage R1is greater than the second differential voltage R2, the control unit120may set the first differential voltage R1as the criterion value R.

Since the differential voltage d7of the seventh peak P7and the differential voltage d8of the eighth peak P8included in the first capacity region RR1are greater than the criterion value R, the control unit120may judge that the battery satisfies the first classification criterion.

In addition, since the differential voltage d9of the ninth peak P9included in the second capacity region RR2is greater than the criterion value R, the control unit120may judge that the battery satisfies the second classification criterion.

Since the battery is judged to satisfy both the first classification criterion and the second classification criterion, the control unit120may classify the battery into the first group. In addition, the control unit120may classify that the battery is a BOL battery or a MOL battery containing 100% graphite-based negative electrode material, and is a reusable battery.

FIG.5is a diagram schematically showing a fourth differential profile DP4according to an embodiment of the present disclosure.

Specifically, the fourth differential profile DP4is a differential profile for a battery containing a LMO (lithium manganese oxide) positive electrode material and 100% non-graphite-based negative electrode material (SiO). In addition, the fourth differential profile DP4is a differential profile generated based on the voltage and capacity of the battery obtained when the battery is charged at a temperature of 25° C. and at a 0.05 C-rate.

The control unit120may detect the tenth peak P10and the eleventh peak P11in the fourth differential profile DP4. In addition, the control unit120may determine the eleventh peak P11having the greatest differential voltage among the tenth peak P10and the eleventh peak P11as the target peak TP4.

The control unit120may determine a value smaller than the differential voltage d11of the target peak TP4by the first reference value r1as the first differential voltage RE Also, the control unit120may determine a value greater than the lowest differential voltage L of the fourth differential profile DP4by the second reference value r2as the second differential voltage R2. Here, since the second differential voltage R2is greater than the first differential voltage R1, the control unit120may set the second differential voltage R2as the criterion value R.

Here, referring to the embodiments ofFIGS.2to5, it cannot be regarded that the first differential voltage R1is always greater than the second differential voltage R2. Therefore, the control unit120sets the criterion value R by comparing the first differential voltage R1determined based on the differential voltage of the target peak and the second differential voltage R2determined based on the lowest differential voltage L with each other.

Since the first capacity region RR1does not include any peak, the control unit120may judge that the battery does not satisfy the first classification criterion. Accordingly, the control unit120may classify the battery into the second group without judging whether the battery satisfies the second classification criterion.

In addition, the control unit120may classify the battery as a battery containing a non-graphite-based negative electrode material or an EOL battery containing a graphite-based negative electrode material, and is a non-reusable battery.

The battery classification apparatus100according to the present disclosure may be applied to a BMS (Battery Management System). That is, the BMS according to the present disclosure may include the battery classification apparatus100described above. In this configuration, at least some of the components of the battery classification apparatus100may be implemented by supplementing or adding functions of the configuration included in the conventional BMS. For example, the profile generating unit110, the control unit120and the storage unit130of the battery classification apparatus100may be implemented as components of the BMS.

In addition, the battery classification apparatus100according to the present disclosure may be provided in a battery pack. That is, the battery pack according to the present disclosure may include the above-described battery classification apparatus100and one or more battery cells. In addition, the battery pack may further include electrical equipment (relays, fuses, etc.) and a case.

FIG.6is a diagram schematically showing an exemplary configuration of a battery pack1according to another embodiment of the present disclosure.

A measuring unit200may be connected to a first sensing line SL1, a second sensing line SL2, and a third sensing line SL3.

Specifically, the first sensing line SL1may be connected to a positive electrode of a battery cell B and the measuring unit200. Also, the second sensing line SL2may be connected to a negative electrode of the battery cell B and the measuring unit200. The measuring unit200may measure the voltage of the battery cell B by calculating the difference between the positive electrode voltage of the battery cell B measured through the first sensing line SL1and the negative electrode voltage of the battery cell B measured through the second sensing line SL2.

Also, the measuring unit200may measure the charging current and/or the discharging current of the battery cell B through an ampere meter A connected to the third sensing line SL3. For example, the ampere meter A may be a shunt resistor or an ammeter.

The battery information about the voltage and current of the battery cell B measured by the measuring unit200may be transmitted to the battery classification apparatus100. Specifically, the profile generating unit110may receive the battery information of the battery cell B from the measuring unit200. In addition, the profile generating unit110may generate a differential profile representing a corresponding relationship between the capacity of the battery cell B and the differential voltage based on the received voltage and current of the battery cell B. In addition, the battery information of the battery cell B measured by the measuring unit200may be stored in the storage unit130.

FIG.7is a diagram schematically showing a battery classification method according to still another embodiment of the present disclosure.

Preferably, each step of the battery classification method may be performed by the battery classification apparatus100. Hereinafter, contents overlapping with the previously described contents will be omitted or briefly described.

Referring toFIG.7, the battery classification method may include a differential profile generating step (S100), a plural peak detecting step (S200), and a battery classifying step (S300).

The differential profile generating step (S100) is a step of generating a differential profile representing a corresponding relationship between a differential voltage based on capacity and voltage of a battery and the capacity, and may be performed by the profile generating unit110.

For example, in the embodiment ofFIG.2, the profile generating unit110may generate a first differential profile DP1representing a corresponding relationship between the capacity of the battery and the differential voltage.

The plural peak detecting step S200is a step of detecting a plurality of peaks in the differential profile, and may be performed by the control unit120.

For example, in the embodiment ofFIG.2, the control unit120may detect a first peak P1, a second peak P2, a third peak P3, and a fourth peak P4.

The battery classifying step (S300) is a step of classifying the battery into any one of a plurality of groups preset based on a plurality of classification conditions preset for the number of the plurality of detected peaks and differential voltage, and may be performed by the control unit120.

Specifically, the control unit120may judge whether the battery satisfies the first classification condition based on the number of peaks included in the first capacity region RR1and the differential voltage. In addition, the control unit120may judge whether the battery satisfies the second classification condition based on the number of peaks included in the second capacity region RR2and the differential voltage.

For example, in the embodiment ofFIG.2, the first peak P1and the second peak P2may be included in the first capacity region RR1, and the third peak P3and the fourth peak P4may be included in the second capacity region RR2. Since the differential voltage dl of the first peak P1and the differential voltage d2of the second peak P2are equal to or greater than the criterion value R, the control unit120may judge that the battery satisfies the first classification condition. In addition, since the differential voltage d3of the third peak P3and the differential voltage d4of the fourth peak P4are also equal to or greater than the criterion value R, the control unit120may judge that the battery satisfies the second classification condition. Accordingly, the control unit120may classify the battery into the first group. In addition, the control unit120may classify that the battery is a BOL battery or a MOL battery containing a graphite-based negative electrode material, and is a reusable battery.

The embodiments of the present disclosure described above may not be implemented only through an apparatus and a method, but may be implemented through a program that realizes a function corresponding to the configuration of the embodiments of the present disclosure or a recording medium on which the program is recorded. The program or recording medium may be easily implemented by those skilled in the art from the above description of the embodiments.

The present disclosure has been described in detail. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the disclosure, are given by way of illustration only, since various changes and modifications within the scope of the disclosure will become apparent to those skilled in the art from this detailed description.

Additionally, many substitutions, modifications and changes may be made to the present disclosure described hereinabove by those skilled in the art without departing from the technical aspects of the present disclosure, and the present disclosure is not limited to the above-described embodiments and the accompanying drawings, and each embodiment may be selectively combined in part or in whole to allow various modifications.

REFERENCE SIGNS

1: battery pack100: battery classification apparatus110: profile generating unit120: control unit130: storage unit200: measuring unit