KR20220032471A - Battery management apparatus, and Energy storage system - Google Patents

Abstract

The present invention relates to an energy storage device, which: obtains voltages of a plurality of battery cells at regular intervals; obtains a total voltage based on the voltages of the plurality of battery cells; obtains a value of a correlation coefficient for each of the plurality of battery cells based on the voltages and the total voltage of each battery cell; generates and stores identification signals corresponding to the plurality of battery cells based on the values of the correlation coefficient and a reference value; monitors the failure risk of the battery cell based on the number of identification signals for each stored battery cell; controls the output of warning information if the risk of failure of the battery cell is less than a standard risk; and controls the charging and discharging of the plurality of battery cells by cutting off if the risk of failure of the battery cell exceeds the standard risk.

Description

A battery management apparatus, an energy storage apparatus having the same, and a control method thereof {Battery management apparatus, and Energy storage system}

The present invention relates to a battery management device for diagnosing overheating of a battery and an energy storage device having the same.

Renewable energy sources such as solar power and wind power have a disadvantage in that they cannot consistently obtain electricity depending on the weather. To this end, recently, a system that can store energy in advance in a storage device and use it at a required time is being used. This is called an energy storage system (ESS: Energy Storage System, energy storage system).

Such an energy storage device can be viewed as a device that efficiently uses electrical energy by applying a storage technology to the characteristics of electricity consumed at the same time as production.

A battery is used as a representative medium of an energy storage device. In this case, the battery may be a newly manufactured battery or a battery that is reused after being used in another device.

A battery is a rechargeable battery capable of charging and discharging, and a battery module including a plurality of cells may be connected in series and in parallel to obtain necessary power.

These plurality of battery cells have a problem in that a relatively high current is input or output during charging or discharging, or a fire occurs in the battery cells due to a failure.

In one aspect, a battery management apparatus for obtaining a value of a correlation coefficient for each battery cell based on an electrical signal of a plurality of battery cells, and predicting a failure of a battery cell based on the obtained value of the correlation coefficient, and energy storage having the same provide the device.

Another aspect is to obtain a standardized score (Z-score) for the electrical signal based on the electrical signal of a plurality of battery cells, monitor the deviation characteristics of the battery cells based on the obtained standardized score, and monitor the deviation characteristics of the battery cells based on the monitoring result. A battery management device for determining a failure and an energy storage device having the same are provided.

A battery management apparatus according to an aspect includes: a plurality of battery cells connected to at least one of a series connection and a parallel connection; a detector for detecting electrical signals of a plurality of battery cells; Obtaining an electrical signal for each of a plurality of battery cells and a value of a correlation coefficient corresponding to a correlation obtained based on the electrical signal, and identification corresponding to the electrical signal of the plurality of battery cells based on the values of the correlation coefficient and a reference value a monitoring unit that generates a signal; and a storage unit for storing the identification signal generated by the monitoring unit for each battery cell, wherein the monitoring unit recognizes the risk of failure of the battery cell based on the number of identification signals for each battery cell stored in the storage unit.

The detecting unit of the battery management apparatus according to an aspect includes: a current detecting unit detecting a current of each battery cell; and at least one of a voltage detector detecting a voltage of each battery cell.

The battery management device according to an aspect further includes a temperature detection unit for detecting a temperature of at least one battery cell, and the monitoring unit is based on the current, voltage, and temperature of each battery cell, and the internal resistance of the battery in the state of charge and the lifespan state and obtaining at least one of a change in capacity corresponding to a change in voltage, and obtaining a value of a correlation coefficient between the plurality of battery cells based on at least one of a state of charge of the battery, an internal resistance of a life state of the battery, and a change in capacity corresponding to a change in voltage. .

The electrical signal of the battery management apparatus according to an aspect includes a voltage signal, and the monitoring unit obtains voltages of a plurality of battery cells based on voltage signals of each of the plurality of battery cells, and based on the voltages of the plurality of battery cells to obtain a total voltage, and a value of a correlation coefficient of each battery cell with respect to the total voltage is obtained.

The monitoring unit of the battery management apparatus according to an aspect generates a first identification signal when the value of the obtained correlation coefficient is greater than or equal to a reference value, and generates a second identification signal when the value of the obtained correlation coefficient is less than the reference value, and generates a second identification Save the signal to the storage unit.

The monitoring unit of the battery management apparatus according to an aspect recognizes a risk of failure of a battery cell based on the number of second identification signals for each battery cell stored in the storage unit.

The monitoring unit of the battery management apparatus according to an aspect obtains a value of a correlation coefficient by using electrical signals of a plurality of battery cells detected for a predetermined time.

The monitoring unit of the battery management apparatus according to an aspect determines the repetition degree and frequency of the number of second identification signals for each battery cell stored in the storage unit.

An energy storage device according to another aspect includes: a battery including a plurality of battery cells connected to at least one of a series connection and a parallel connection; a detector for detecting electrical signals of a plurality of battery cells; Obtaining an electrical signal for each of a plurality of battery cells and a value of a correlation coefficient corresponding to a correlation obtained based on the electrical signal, and identification corresponding to the electrical signal of the plurality of battery cells based on the values of the correlation coefficient and a reference value a battery management device for generating and storing signals, and monitoring a risk of failure of a battery cell based on the number of stored identification signals for each battery cell; a controller for controlling the output of warning information based on the risk of failure of the battery cells, and controlling charging and discharging of the plurality of battery cells; and a display unit for displaying warning information based on a control command of the controller.

The detection unit of the energy storage device according to another aspect may include a current detection unit configured to detect a current of each battery cell; and at least one of a voltage detector detecting a voltage of each battery cell.

The energy storage device according to another aspect further includes a temperature detection unit for detecting a temperature of at least one battery cell, wherein the battery management device includes a state of charge and a lifespan of a battery based on a current, voltage, and temperature of each battery cell. obtain at least one of a state internal resistance and a capacity change corresponding to a voltage change, and obtain a correlation between the plurality of battery cells based on at least one of a state of charge of the battery, a life state internal resistance, and a capacity change corresponding to a voltage change do.

According to another aspect, the electrical signal of the energy storage device includes a voltage signal, and the battery management device obtains the voltages of the plurality of battery cells based on the voltage signals of each of the plurality of battery cells, and the voltages of the plurality of battery cells A total voltage is obtained based on , and a value of a correlation coefficient of each battery cell with respect to the total voltage is obtained.

The energy storage device according to another aspect further includes a storage unit, wherein the battery management device generates a first identification signal when the value of the obtained correlation coefficient is greater than or equal to the reference value, and when the value of the obtained correlation coefficient is less than the reference value, the second identification A signal is generated and the second identification signal is stored in the storage unit.

A battery management apparatus of an energy storage device according to another aspect recognizes a risk of failure of a battery cell based on the number of second identification signals for each battery cell stored in the storage unit.

A battery management apparatus of an energy storage device according to another aspect determines the repetition degree and frequency of the number of second identification signals for each battery cell stored in the storage unit.

A battery management apparatus of an energy storage device according to another aspect manages a battery module in which a plurality of battery cells are connected in series and in parallel.

A battery management apparatus for an energy storage device according to another aspect manages a battery rack including a plurality of battery modules connected in series and parallel, and each battery module includes battery cells connected in series and parallel.

An energy storage device according to another aspect includes: a battery including a plurality of battery cells connected in at least one of a series connection and a parallel connection; a detector for detecting electrical signals of a plurality of battery cells; Obtaining an electrical signal for each of a plurality of battery cells and a value of a correlation coefficient corresponding to a correlation obtained based on the electrical signal, and an average value and a standard value based on a voltage value corresponding to the electrical signal for each of the plurality of battery cells obtaining a deviation, obtaining a standardized score of each battery cell based on the voltage value, average value and standard deviation of each battery cell, and obtaining each battery cell based on the values of the correlation coefficient and the standardization score of each battery cell a battery management device generating an identification signal corresponding to a cell and monitoring a failure risk of each battery cell based on the identification signal corresponding to each battery cell; a control unit for controlling the output of warning information based on the risk of failure of each battery cell, and for blocking and controlling charging and discharging of each battery cell; and a display unit for displaying warning information based on a control command of the controller.

A detection unit of an energy storage device according to another aspect includes a current detection unit configured to detect a current of each battery cell; and at least one of a voltage detector detecting a voltage of each battery cell.

The electrical signal of the energy storage device according to another aspect includes a voltage signal, and the battery management device obtains the voltages of the plurality of battery cells based on the voltage signals of each of the plurality of battery cells, and A total voltage is obtained based on the voltage, and a value of a correlation coefficient of each battery cell with respect to the total voltage is obtained.

The battery management device of the energy storage device according to another aspect generates a first identification signal when the value of the obtained correlation coefficient is greater than or equal to a reference value, and generates a second identification signal when the value of the obtained correlation coefficient is less than the reference value, When the obtained standardization score is equal to or less than the reference standardization score, a first identification signal is generated, and when the obtained standardization score exceeds the reference standardization score, a second identification signal is generated.

A battery management apparatus for an energy storage device according to another aspect recognizes a risk of failure of a battery cell based on the number of second identification signals of each battery cell.

According to the present invention, by defining the correlation of the operating states between the battery cells as a correlation coefficient and monitoring the states of the battery cells based on the correlation coefficient, it is possible to effectively monitor the states of individual battery cells in a battery composed of a plurality of battery cells.

The present invention can prevent the failure of the battery in advance by diagnosing the failure of the battery cells through monitoring.

In the present invention, when at least one battery cell malfunctions, an identification signal for the battery cell that has performed the abnormal operation is generated and the battery cell is accumulatively monitored to diagnose the failure of an individual battery cell exhibiting different operating characteristics from the operation of other battery cells. , it can be diagnosed before a battery cell reaches a critical condition.

The present invention can prevent accidents such as fire and explosion due to chain energy release and temperature rise by diagnosing a failure of at least one battery cell before the thermal runaway phenomenon in at least one battery cell progresses.

In the present invention, even for battery cells connected in parallel (when the cell problematic with + and the cell problem with - exist together), by monitoring the trend value/trend change, the parallel connection group with an abnormality (that is, the parallel connection position where the abnormality occurred) ) can be estimated.

As described above, the present invention can prevent a fire caused by a battery.

The present invention can improve the quality and marketability of the battery management device and the energy storage device, further increase user satisfaction, improve user convenience, reliability, and safety, and secure product competitiveness.

1A is an exemplary diagram of an energy storage device according to an embodiment;
1B is an exemplary view of a battery rack in the energy storage device shown in FIG. 1A .
1C is an exemplary diagram of a battery module of the energy storage device shown in FIG. 1B .
2 is a block diagram of an energy storage device according to an embodiment.
3 is an exemplary view of a vehicle according to an embodiment.
4A is a detailed configuration diagram of an apparatus for managing a battery of an energy storage device according to an embodiment.
4B is a detailed configuration diagram of a monitoring unit of a battery management device of an energy storage device according to an embodiment.
5A and 5B are diagrams illustrating acquisition of total voltage information for each of a plurality of battery cells in a battery management apparatus of an energy storage device according to an embodiment.
6A is a diagram illustrating an example of obtaining total voltage information for each of a plurality of battery modules in a battery management apparatus of an energy storage device according to an embodiment.
Figure 6b is an example of obtaining the total voltage information for each of a plurality of battery racks in the battery management device of the energy storage device according to the embodiment.
7 is a correlation graph of variables corresponding to values of correlation coefficients calculated by a battery management device of an energy storage device according to an embodiment.
8A is a graph showing voltage changes of a plurality of battery cells provided in an energy storage device according to an embodiment, and FIG. 8B is a graph showing correlation coefficients of the plurality of battery cells.
8C is a graph showing voltage changes of a plurality of battery cells provided in the energy storage device according to the embodiment, and FIG. 8D is a graph showing correlation coefficients of the plurality of battery cells. In an example of an experiment different from FIGS. 8A and 8B is a graph for
8E is a graph of standard deviation and standardized scores.
8F is a graph showing voltage changes of a plurality of battery cells provided in the energy storage device according to an embodiment, and FIG. 8G is a graph showing standardized scores of the plurality of battery cells.
9A and 9B are exemplary diagrams of information related to an identification signal accumulated and stored in a battery management device of an energy storage device according to an embodiment.
10 is a control flowchart of an energy storage device according to an embodiment.

Like reference numerals refer to like elements throughout. This specification does not describe all elements of the embodiments, and general content in the technical field to which the present invention pertains or content that overlaps among the embodiments is omitted. The term 'unit, module, device' used in this specification may be implemented in software or hardware, and according to embodiments, a plurality of 'part, module, device' may be implemented as one component, or one 'unit, It is also possible for a module or device' to include a plurality of components.

Throughout the specification, when a part is "connected" to another part, it includes not only direct connection but also indirect connection, and indirect connection includes connection through a wireless communication network. do.

In addition, when a part "includes" a certain component, this means that other components may be further included, rather than excluding other components, unless otherwise stated.

Terms such as first, second, etc. are used to distinguish one component from another, and the component is not limited by the above-mentioned terms.

The singular expression includes the plural expression unless the context clearly dictates otherwise.

In each step, the identification code is used for convenience of description, and the identification code does not describe the order of each step, and each step may be performed differently from the specified order unless the specific order is clearly stated in the context. there is.

Hereinafter, the working principle and embodiments of the present invention will be described with reference to the accompanying drawings.

1A is an exemplary diagram of an energy storage device according to an embodiment, FIG. 1B is an exemplary diagram of a battery rack in the energy storage device illustrated in FIG. 1A, and FIG. 1C is an example of a battery module of the energy storage device illustrated in FIG. 1B It is also

The energy storage device 1 is a device that stores energy and outputs energy so that the stored energy can be used when necessary.

For example, the energy storage device 1 may be applied to a new renewable energy technology or a smart grid technology.

As shown in Figure 1a, the energy storage device 1 is a plurality of battery racks 10 connected in parallel, and an energy management system for managing and controlling a plurality of battery racks 10 (EMS: Energy management system, 20) includes

The energy management system 20 may deliver the rack monitoring information, such as the state of charge and the lifespan of each battery rack, to the battery management device.

As shown in Figure 1b, each battery rack 10, includes a plurality of battery modules 11 connected in series and parallel. Here, a plurality of battery modules may form one battery rack. Each battery rack 10 includes a rack management system (rack BMS, 12) for managing and controlling a plurality of battery modules (11).

As shown in FIG. 1C , each battery module 11 includes a plurality of battery cells 11a connected in series and parallel. Here, the plurality of battery cells 11a may form one battery module.

Each battery module 11 includes a module management system (module BMS, 11a) for managing and controlling the plurality of battery cells 11a.

The energy storage device 1 may further include a power converter (not shown) that converts externally supplied power into power for charging the plurality of battery cells and supplies the converted power to the plurality of battery cells. Here, the power supplied from the outside may be power from the power grid.

As shown in FIG. 2 , the energy storage device 1 communicates with at least one of the energy management system 20 , the rack management system 11 and the module management system 11b to each management system 20 , 12, 11b) may include a battery management device 110 for monitoring the state of the battery cell, battery module and battery rack.

That is, the battery management device 110 receives the state information of the battery racks from the energy management system 20, receives the state information on the battery modules from the rack management system 11, and to a plurality of cells from the module management system 11b. Receive status information for and monitor the status of the battery cells, battery modules and battery racks based on the received various information.

The energy storage device 1 may include a module management system for managing battery cells, a rack management system for managing battery modules, and an energy management system for managing battery racks, but includes a module management system, a rack management system and energy As an integrated management system, a single management system for managing battery cells, battery modules, and battery racks may be included.

In addition, the battery management device provided in the energy storage device 1 communicates with one management system and receives status information of battery cells, battery modules, and battery racks from one management system, so that the battery cells and the battery modules It is also possible to monitor and control all of the battery racks.

Such a battery management device will be described later.

The battery management apparatus may manage a battery provided in the eco-friendly vehicle 2 . That is, the eco-friendly vehicle may include a battery management device.

3 is an exemplary view of a vehicle according to an embodiment.

The vehicle according to the embodiment is an eco-friendly vehicle, and may be a hybrid vehicle or an electric vehicle. In this embodiment, an electric vehicle will be described as an example.

As shown in FIG. 3 , the power unit of the vehicle 2 includes a battery 100 , a motor 200 , a motor driving unit 300 , a speed reducer 400 , and a slow charging unit 500 .

The battery 100 may include a plurality of battery cells that generate a high-voltage current to supply driving power to the vehicle.

The vehicle may further include a fan for lowering the temperature of the battery 100 . The battery may consist of a plurality of battery racks, and each battery rack may include a plurality of battery modules connected in series and in parallel. And each battery module may include a plurality of battery cells connected in series and in parallel. Each battery rack can be connected in parallel.

That is, the most basic unit of the battery may be a battery cell, and each battery cell may have a voltage of 2.5V to 4.2V basically.

These battery cells may be collected to become a battery module, and battery modules may be collected to become a battery rack. A plurality of battery racks may be connected in series and parallel.

In addition, according to the technical field, one battery cell is also called a battery, one battery module is also called a battery, and one battery rack is also called a battery. In this embodiment, a plurality of racks connected in series and in parallel are referred to as batteries.

The vehicle may further include a power converter (not shown).

The power converter converts externally supplied power into power for charging the battery and supplies the converted power to the battery. Here, the externally supplied power may be power from a charging station or a power grid.

The motor 200 generates rotational force by using electric energy of the battery and transmits the generated rotational force to the wheels to drive the wheels.

The motor 200 converts electrical energy of the battery into mechanical energy for operating various devices provided in the vehicle.

When the boot button is turned on, the motor 200 is supplied with a maximum current to generate a maximum torque.

The motor 200 may operate as a generator under energy regeneration conditions by braking, deceleration, steel plate driving, or low-speed driving to charge the battery 100 .

The motor driving unit 300 drives the motor 200 in response to a control command from the control unit. The motor driving unit 300 may include an inverter that converts battery power into driving power of the motor 200 .

When outputting driving power of the motor 200 , the inverter outputs driving power of the motor 200 based on a target vehicle speed according to a user command. Here, the driving power of the motor 200 may vary according to a switching signal for outputting a current corresponding to the target vehicle speed and a switching signal for outputting a voltage corresponding to the target vehicle speed. That is, the inverter may include a plurality of switching elements.

The inverter may also transfer power generated from the motor 200 to the battery during regenerative braking. That is, the inverter may also perform a function of changing the direction and output of the current between the motor 200 and the battery.

The speed reducer 400 reduces the speed of the motor 200 and transmits the rotational force obtained by increasing the torque of the motor 200 to the wheel.

The vehicle may further include a charging unit that is provided on the exterior of the vehicle body, is connected to a charging cable, and receives power for charging the battery.

The charging unit may include a fast charging unit for rapidly charging the battery, and a slow charging unit 500 for charging the battery at a slow rate that is slower than the fast charging rate.

A cable for fast charging may be connected to the fast charging unit, and a cable for slow charging may be connected to the slow charging unit 500 .

In addition, the fast charging unit for fast charging and the slow charging unit for slow charging, which has a slower charging speed than the fast charging, may be provided at the same location on the exterior of the vehicle or may be provided at different locations.

The slow charging unit 500 converts external commercial power (AC) into rectification and direct current and delivers it to the battery. For example, the slow charger 500 may include an AC rectifier, a power factor correction (PFC), a converter, and a capacitor.

The fast charging unit may include at least one of a terminal and a cable for directly connecting the external fast charger and the battery.

4A is a diagram illustrating a control configuration of a battery management apparatus according to an embodiment, and FIG. 4B is a detailed configuration diagram of a monitoring unit in the battery management apparatus shown in FIG. 4A . The battery management device may be a battery management device provided in an energy storage device or a battery management device provided in a vehicle.

As shown in FIG. 4A , the battery management device 110 includes a voltage detection unit 111 , a current detection unit 112 , a temperature detection unit 113 , a monitoring unit 114 , a storage unit 115 , and a communication unit 116 . may include The energy storage device may further include a control unit 120 and a display unit 130 .

The battery management device 110 monitors the state of the battery. Such a battery management device 110 can monitor the state of each battery cell by using the battery cell as a unit, and can monitor the state of each battery module by using the battery module as a unit, and a battery rack You can monitor the status of each battery rack as a unit of .

The battery management apparatus 110 recognizes a battery cell having a possibility of failure among a plurality of battery cells based on the monitoring result and outputs information on the recognized battery cell.

The battery management apparatus 110 may recognize a battery module having a failure possibility among a plurality of battery modules based on the monitoring result and output information on the recognized battery module.

The battery management device 110 may recognize a battery rack having a failure possibility among a plurality of battery racks based on the monitoring result and output information about the recognized battery rack.

A detailed configuration of the battery management apparatus 110 will be described later.

The battery 100 and the battery management apparatus 110 may be referred to as a battery management system (BMS).

The controller 120 may control the operation of the display unit 130 to output the battery state information transmitted from the battery management apparatus 110 . The controller 120 may also control the operation of the sound output unit (not shown) so that the state information of the battery transmitted from the battery management apparatus 110 is output.

The controller 120 may control operations of various electronic devices based on battery state information transmitted from the battery management device 110 .

For example, when it is determined that the state information of the battery transmitted from the battery management device 110 is abnormal information of at least one battery cell, the controller 120 controls the output of abnormal information of at least one battery cell, and various electronic devices. It is possible to cut off the power supplied to the device.

When it is determined that the state information of the battery transmitted from the battery management device 110 is abnormal information of at least one battery cell, the controller 120 may selectively cut off power supplied to various electronic devices.

When a plurality of battery management devices 110 are provided, the controller 120 obtains battery status information by combining information transmitted from the plurality of battery management devices 110 and controls the output of the obtained battery status information. It is also possible

The control unit 120 controls an algorithm for controlling the operation of the components in the energy storage device 1 or the vehicle 2 or a memory (not shown) for storing data for a program reproducing the algorithm, and data stored in the memory. It may be implemented as a processor (not shown) that performs the above-described operation using In this case, the memory and the processor may be implemented as separate chips. Alternatively, the memory and the processor may be implemented as a single chip.

The display unit 130 displays abnormality information of the battery in response to a control command from the control unit 120 . Here, the abnormality information of the battery may include information on the possibility of occurrence of a failure.

The display unit 130 may display battery management information and may also display current battery charge state information.

The display unit 130 may also display the identification information of the battery cell where the abnormality occurs, the identification information of the battery module or the identification information of the battery rack, or the position information of the battery cell where the abnormality occurs, the position information of the battery module or the battery rack It is also possible to display the location information of

The display unit 130 may display guide information on thermal runaway of the battery as an image.

The display unit 130 may also display the temperature and gas amount of the battery.

The energy storage device may further include a sound output unit (not shown).

The sound output unit (not shown) outputs guide information on thermal runaway of the battery as a sound such as a warning sound. Here, the sound output unit may include a speaker.

Hereinafter, the battery management apparatus 110 will be described.

The battery management apparatus 110 is a detector that detects a state of charge of the battery to monitor the state of the battery, and includes a voltage detector, a current detector, and a temperature detector.

Here, the voltage detection unit and the current detection unit may be a detection unit that detects an electrical signal for each cell of the battery.

The voltage detector 111 detects a voltage of the battery 100 and outputs a voltage signal corresponding to the detected voltage.

The number of voltage detectors 111 may be plural.

The plurality of voltage detectors may be connected to output terminals of the plurality of battery cells to respectively detect voltages of the plurality of cells.

The plurality of voltage detectors may be connected to output terminals of the plurality of battery modules to respectively detect voltages of the plurality of modules.

The plurality of voltage detection units may be connected to the output terminals of the plurality of battery racks to respectively detect the voltages of the plurality of racks.

The battery management apparatus 110 may further include a switch (not shown) connected to the voltage detector 111 . The switch may be selectively connected to a plurality of cells. The voltage detection unit 111 may respectively detect voltages of a plurality of cells in response to a change in the on-contact of the switch and output a voltage signal corresponding to the voltages of the detected cells, respectively.

The current detection unit 112 detects a current of the battery and outputs a current signal corresponding to the detected current.

There may be a plurality of current detectors 112 .

The plurality of current detectors 112 may respectively detect currents flowing through the plurality of battery cells.

The plurality of current detection units 112 may respectively detect currents flowing through the plurality of battery modules.

A plurality of current detection unit 112 may detect each current flowing through a plurality of battery racks.

The temperature detection unit 113 detects the temperature of the battery 100 and outputs a temperature signal for the detected temperature. The temperature detection unit 113 may be provided inside the battery rack.

The number of temperature detectors 113 may be plural.

The plurality of temperature detectors 113 may be provided in each of the plurality of battery cells, and may detect temperatures of the plurality of battery cells, respectively.

The plurality of temperature detectors 113 may be provided in each of the plurality of battery modules, and may detect temperatures of the plurality of battery modules, respectively.

A plurality of temperature detection unit 113 may be provided in each of the plurality of battery racks, it is possible to detect the temperature of each of the plurality of battery racks.

The monitoring unit 114 monitors the state of charge of the battery based on the detected current of the battery.

The monitoring unit 114 may monitor the state of charge of the battery based on the detected current and voltage of the battery.

The monitoring unit 114 may monitor the state of charge (SOC) of the battery based on the current, voltage, and temperature of each cell of the battery.

Here, the state of charge of the battery may include the amount of charge of the battery.

That is, the monitoring unit 114 may acquire the state of charge of the battery corresponding to the current, voltage, and temperature of the battery from a table stored in advance. In the pre-stored table, the amount of charge of the battery corresponding to the correlation between the current, voltage, and temperature of the battery may be matched.

The monitoring unit 114 may acquire a state of health (SOH), internal resistance (R), and capacity change (dQ/dV) for voltage change.

The monitoring unit 114 may acquire the internal resistance R based on the voltage and current of the battery.

When a boot-on command is received from the controller 120 , the monitoring unit 114 checks the state of charge of the battery and outputs charge state information on the confirmed state of charge of the battery to the controller 120 .

The monitoring unit 114 may output the acquired state of health (SOH), internal resistance (R ), and capacity change (dQ/dV) with respect to voltage change to the control unit 120 .

The monitoring unit 114 is based on at least one of voltage, current, temperature of the battery, state of charge (SOC) of the battery, state of life (SOH), internal resistance (R ), and capacity change (dQ/dV) with respect to voltage change to determine whether at least one battery cell is in an abnormal state.

When determining whether the battery cell is in an abnormal state, the monitoring unit 114 generates an identification signal for managing the battery state based on the received detection information, and determines whether the battery cell is in an abnormal state based on the generated identification signal can do. Here, the identification signal may be zero (0) or one (1).

The monitoring unit 114 may determine whether the at least one battery module is in an abnormal state, and may determine whether the at least one battery rack is in an abnormal state.

The monitoring unit 114 for determining whether at least one battery cell is in an abnormal state may include an information obtaining unit 114a, a signal generating unit 114b, and a recognizing unit 114c.

In addition, the information obtaining unit 114a, the signal generating unit 114b, and the recognizing unit 114c may be provided separately from the monitoring unit 114 to transmit/receive information to and from the monitoring unit 114 . The configuration of the information obtaining unit 114a, the signal generating unit 114b, and the recognizing unit 114c will be described later with reference to FIG. 4B.

The monitoring unit 114 may turn on a switch unit (not shown) when the battery is in a normal state. When it is determined that the state of the battery is a thermal runaway state, the monitoring unit 114 may stop charging and discharging of the battery by controlling the switch unit to be turned off.

Here, the switch unit may perform an on operation when the battery is in a normal state and may perform an off operation when the battery is in a thermal runaway state. The switch unit may include a relay for supplying and blocking power charged in the battery 100 to the motor. Such a switch unit can protect the battery and ensure electrical safety.

The monitoring unit 114 may determine thermal runaway based on the temperature information detected by the temperature detection unit 113 .

The monitoring unit 114 cools the battery 100 by controlling the rotation speed of the fan based on the cell temperature information of the battery cells.

When it is determined that the battery state is a thermal runaway state, the monitoring unit 114 controls the driving of the fan so that the fan rotates at the maximum rotational speed. In this way, the gas generated from the battery can be discharged to the outside.

When it is determined that the battery state is a thermal runaway state, the monitoring unit 114 may directly transmit information about the thermal runaway to the display unit 130 or to the control unit 120 .

The monitoring unit 114 uses a memory (not shown) that stores data for an algorithm or a program that reproduces an algorithm for controlling the operation of the components in the battery management system (BMS), and the above-described data stored in the memory. It may be implemented as a processor (not shown) that performs an operation. In this case, the memory and the processor may be implemented as separate chips. Alternatively, the memory and the processor may be implemented as a single chip.

The storage unit 115 may store a table in which the state of charge of the battery is matched to the correlation between the current, voltage, and temperature of the battery.

The storage unit 115 may store a table in which a charge amount of a battery corresponding to a correlation between current, voltage, and temperature of the battery is matched.

The storage unit 115 may store a deterioration rate corresponding to the period of use.

The storage unit 115 may be a memory implemented as a separate chip from the processor described above with respect to the monitoring unit 114 , or may be implemented as a single chip with the processor.

The storage unit 115 is a nonvolatile memory device or RAM such as a cache, read only memory (ROM), programmable ROM (PROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), and flash memory. It may be implemented as at least one of a volatile memory device such as (Random Access Memory), a hard disk drive (HDD), or a storage medium such as a CD-ROM, but is not limited thereto.

The communication unit 116 communicates with the control unit 120 and transmits battery status information to the control unit 120 .

The communication unit 116 may include one or more components that enable communication with the control unit 120 , and may include, for example, at least one of a short-range communication module, a wired communication module, and a wireless communication module.

The short-distance communication module transmits signals using a wireless communication network in a short distance such as a Bluetooth module, an infrared communication module, an RFID (Radio Frequency Identification) communication module, a WLAN (Wireless Local Access Network) communication module, an NFC communication module, and a Zigbee communication module. It may include various short-distance communication modules for transmitting and receiving.

The wired communication module includes various wired communication modules such as a Controller Area Network (CAN) communication module, a Local Area Network (LAN) module, a Wide Area Network (WAN) module, or a Value Added Network (VAN) module. Various cable communication such as USB (Universal Serial Bus), HDMI (High Definition Multimedia Interface), DVI (Digital Visual Interface), RS-232 (recommended standard232), power line communication, or POTS (plain old telephone service) as well as communication module It can contain modules.

In addition to the Wi-Fi module and the wireless broadband module, the wireless communication module includes global system for mobile communication (GSM), code division multiple access (CDMA), wideband code division multiple access (WCDMA), and universal mobile telecommunications system (UMTS). ), Time Division Multiple Access (TDMA), Long Term Evolution (LTE), etc. may include a wireless communication module supporting various wireless communication methods.

At least one component may be added or deleted according to the performance of the components of the battery management apparatus illustrated in FIG. 4A . In addition, it will be readily understood by those of ordinary skill in the art that the mutual positions of the components may be changed corresponding to the performance or structure of the system.

Meanwhile, each component illustrated in FIG. 4A refers to a hardware component such as software and/or a Field Programmable Gate Array (FPGA) and an Application Specific Integrated Circuit (ASIC).

As shown in FIG. 4B , the monitoring unit 114 may include an information obtaining unit 114a, a signal generating unit 114b, and a recognizing unit 114c.

The information acquisition unit 114a receives the detection signals detected by the voltage detection unit 111, the current detection unit 112, and the temperature detection unit 113, and receives voltage information, current information and Acquire temperature information. Here, the detection signal may include a voltage signal, a current signal, and a temperature signal.

The information acquisition unit 114a may acquire voltage information, current information, and temperature information of each battery cell when acquiring voltage information, current information, and temperature information of the battery with a predetermined period of time, and Voltage information, current information and temperature information can be obtained, and voltage information, current information and temperature information of each battery rack can be obtained.

The information acquisition unit 114a may acquire total voltage information and total current information for a plurality of battery cells.

The information acquisition unit 114a may acquire total voltage information and total current information for each of a plurality of battery modules, and may acquire total voltage information and total current information for each of a plurality of battery racks.

An example of the information obtaining unit 114a for obtaining total voltage information for each of a plurality of battery cells will be described with reference to FIGS. 5A and 5B .

As shown in FIG. 5A , a plurality of battery cells may be connected in parallel, and as shown in FIG. 5B , a plurality of battery cells may be connected in series.

As shown in FIG. 5A , when a plurality of battery cells are connected in parallel, the information obtaining unit 114a obtains respective voltage information V1, V2, and V3 for voltages of the plurality of battery cells connected in parallel. Also, voltage information (Vtotal) for the total voltages of a plurality of battery cells connected in parallel may be obtained.

In this case, the information obtaining unit 114a may obtain 4.2V as voltage information on the voltage of each battery cell, and obtain 4.2V as voltage information on the total voltage of a plurality of battery cells connected in parallel with each other. there is. That is, when a plurality of battery cells having the same voltage are connected in parallel, the voltages of the individual battery cells may be equal to the total voltage.

The total capacity Ah of the plurality of battery cells connected in parallel to each other increases by the number of battery cells. That is, the information acquisition unit 114a may acquire the total capacity Ah of the plurality of battery cells based on the number of the plurality of battery cells connected in parallel.

As shown in FIG. 5B, when a plurality of battery cells are connected in series, the information obtaining unit 114a obtains respective voltage information V1, V2, and V3 for voltages of the plurality of battery cells connected in series. Also, voltage information (Vtotal) for the total voltage of a plurality of battery cells connected in series may be obtained.

In this case, the information acquisition unit 114a may obtain 4.2V as voltage information on the voltage of each battery cell, and may obtain 12.6V as voltage information on the total voltage of a plurality of battery cells connected in series with each other. there is. That is, when a plurality of battery cells having the same voltage are connected in series, the sum of voltages of the plurality of battery cells may be the total voltage of the plurality of battery cells connected in series.

When a plurality of battery cells having the same voltage are connected in series, the total capacity Ah may be equal to the capacity of one battery cell. That is, the information acquisition unit 114a may acquire the total capacity Ah of the plurality of battery cells corresponding to the capacity of one of the plurality of battery cells connected in series.

An example of the information acquisition unit 114a for acquiring total voltage information for each of the plurality of battery modules will be described with reference to FIG. 6A .

The battery module may include a plurality of battery sets connected in series. Here, each battery set may include a plurality of battery cells connected in parallel.

The information obtaining unit 114a may obtain voltage information about the voltage of each battery set.

Since a plurality of battery cells are connected in parallel in each battery set, the total voltage in each battery set may be equal to the voltage of the cells of one battery.

The information acquisition unit 114a may acquire voltage information about the total voltage of the battery module based on the voltage information V1, V2, .., Vn of the plurality of battery sets.

That is, since the plurality of battery sets are connected in series, the information obtaining unit 114a may acquire voltage information (Vm-total) for the voltage of the battery module by summing all voltages of the plurality of battery sets.

An example of the information acquisition unit 114a for acquiring the total voltage information for each of a plurality of battery racks will be described with reference to FIG. 6b.

The battery rack may include a plurality of (k) battery modules shown in FIG. 6a.

A plurality of battery modules may be connected in series or in parallel.

When a plurality of battery modules are connected in parallel, the information acquisition unit 114a may acquire the voltage of one battery module as voltage information about the total voltages of the plurality of battery modules.

When a plurality of battery modules are connected in series, the information obtaining unit 114a sums all voltages of the plurality of battery modules and obtains the summed total voltage as voltage information (Vr-total) for the total voltages of the plurality of battery modules. can do.

The information acquisition unit 114a may acquire voltage information of individual battery cells and total voltage information of batteries as highly correlated information.

The information acquisition unit 114a may acquire current information of individual battery cells and total current information of the battery as highly correlated information.

The information acquisition unit 114a acquires the state of charge of the battery based on the detected current of the battery.

The information acquisition unit 114a may acquire the state of charge of the battery based on the detected current and voltage of the battery.

The information obtaining unit 114a may also obtain a state of charge (SOC) of the battery based on the current, voltage, and temperature of each cell of the battery.

Here, the state of charge of the battery may include the amount of charge of the battery.

That is, the information acquisition unit 114a may acquire the state of charge of the battery corresponding to the current, voltage, and temperature of the battery from a table stored in advance. In the pre-stored table, the amount of charge of the battery corresponding to the correlation between the current, voltage, and temperature of the battery may be matched.

The information acquisition unit 114a may acquire a state of health (SOH), internal resistance (R), and capacity change (dQ/dV) with respect to voltage change.

The information obtaining unit 114a may obtain a deterioration rate of the battery based on the temperature of the battery and a charging rate of the battery, and obtain a lifespan state of the battery based on the obtained deterioration rate of the battery.

The charge rate of the battery may be a ratio of a chargeable amount of a total amount of charge in the battery.

The information obtaining unit 114a may obtain a battery deterioration rate corresponding to the usage period of the battery from the information stored in the storage unit 115 .

The information obtaining unit 114a may obtain a deterioration rate of the battery based on the reduced capacity compared to the rated capacity of the battery.

The signal generator 114b receives at least one of voltage, current, temperature, state of charge (SOC) of the battery, state of life (SOH), internal resistance (R ) and capacity change (dQ/dV) for voltage change of the battery Analyze and generate an identification signal corresponding to the abnormal state of the battery based on the analysis result, and output the generated identification signal.

Here, the abnormal state of the battery may be an abnormal state of at least one battery cell, may be an abnormal state of at least one battery module, and may be an abnormal state of at least one battery rack.

The signal generating unit 114b analyzes the correlation of the information acquired by the information acquisition unit 114a, and continues the correlation from the first value (1) to the second value (-1) based on the analyzed correlation. It is acquired as a signal and it is determined whether the continuous signals are similar, and if the continuous signals are similar, a first identification signal is generated, and if the continuous signals are not similar, a second identification signal is generated.

The first identification signal may be zero (0) or one (1), and the second identification signal may be a signal different from the first identification signal.

An example of generating an identification signal corresponding to an abnormal state of a battery cell will be described with reference to FIGS. 7 and 8A and 8B .

The signal generator 114b obtains a value of a correlation coefficient corresponding to a correlation of an electric signal for each of a plurality of battery cells, and identifies the electric signal corresponding to the electric signal of the plurality of battery cells based on the values of the correlation coefficient and a reference value generate a signal

More specifically, when the total voltage of the battery and the individual battery cell voltage are received, the signal generating unit 114b accumulates and stores the received information based on the received time, and stores the average value of the accumulated and stored total voltage for a predetermined time and each An average value of battery cell voltages is calculated, covariance is obtained using the average of the calculated total voltages and an average value of each battery cell voltage, and a product of standard deviation is obtained.

Here, the covariance may be a numerator in Equation (1). And the standard deviation may be the denominator in Equation (1).

rx,y : correlation coefficient of x and y

total voltage information,

voltage information of the i-th battery cell,

Voltage information received for a period of time (n),

σ: standard deviation over a period of time (n), μ: average over a period of time (n)

Equation (1) is an expression for calculating the value of the correlation coefficient, which indicates the degree of correlation between two variables as an exponent. That is, Equation (1) may be an expression for calculating the value of the correlation coefficient of the battery cell voltage with respect to the total voltage.

In the relationship between covariance and two variables X and Y, if covariance is greater than 0, Y also increases when X increases, and when covariance is less than 0, when X increases, Y decreases, and when covariance is 0, there is a difference between the two variables. It means there is no correlation.

When this covariance is divided by the variances of X and Y, a correlation coefficient is calculated, thereby outputting a positive and negative correlation and the magnitude of the correlation. The magnitude of the correlation has a value of 1 to -1 including 0.

That is, the signal generator 114b may calculate the value of the correlation coefficient as a continuous signal based on Equation (1), and may calculate it as a continuous signal from the first value (1) to the second value (-1).

As shown in FIG. 7 , when the value of the correlation coefficient has a positive value, when one variable increases, the other variable also increases, and when one variable decreases, the other variable also decreases.

When the value of the correlation coefficient has a negative value, when one variable increases, the other variable decreases, and when one variable decreases, the other variable increases.

When the value of the correlation coefficient is 0, it indicates that the two variables are completely independent.

The signal generator 114b may determine whether the tendency of voltage change between one battery cell and the other battery cells is similar or different by calculating the value of the correlation coefficient of the voltage of each battery cell with respect to the total voltage.

That is, when the voltage signal of each battery cell is input, the signal generator 114b determines whether the voltage signals between the battery cells disposed adjacent to each other have a similar tendency to each other, and when it is determined that the voltage signal of each battery cell has a similar tendency, a value close to 1 is obtained. and output the identification number of the battery cell when it is determined that they have different tendencies.

The signal generator 114b may generate an identification signal corresponding to the state of the battery using signals having the same cross-correlation relationship. Here, the same correlation may be a relationship in which the correlation coefficient is a reference value (eg, 0.5).

For example, signals having the same cross-correlation relationship may be a signal for a total voltage and a signal for a voltage of each battery cell.

8A is a graph showing voltage changes of a plurality of battery cells, and FIG. 8B is a graph showing correlation coefficients of a plurality of battery cells.

The signal generator 114b checks the calculated values of the correlation coefficients of the plurality of battery cells, respectively, generates and outputs a first identification signal for a correlation coefficient equal to or greater than a reference value among the checked correlation coefficient values, and outputs the first identification signal, which is less than the reference value. A second identification signal is generated and output for the correlation coefficient of .

As shown in FIG. 8B , when the voltage of one battery cell exhibits a different tendency from the voltage of another battery cell, a value of the correlation coefficient less than a reference value (approximately 0.5) may be calculated. In this case, the identification number of the battery cell may be output.

The signal generator 114b may also recognize an abnormal state of at least one battery cell using various anomaly detection algorithms such as a classification algorithm and a clustering algorithm.

8C is a graph of voltage changes of a plurality of battery cells, and FIG. 8D is a graph showing correlation coefficients of a plurality of battery cells, according to an example of an experiment different from those of FIGS. 8A and 8B .

Even in this case, when the signal generator 114b determines that the voltage values of the plurality of battery cells have the same or similar tendency to each other, the correlation coefficient is calculated as a value close to 1, and the voltage value of at least one of the plurality of battery cells is If it is determined that it has a different tendency from the rest of the voltage values, the correlation coefficient is calculated as a value close to 0, the values of the calculated correlation coefficients are checked, respectively, and among the values of the confirmed correlation coefficients, the correlation coefficient is higher than the reference value (approximately 0.5). A first identification signal (eg, 1) is generated for output, and a second identification signal (eg, 0) is generated and output for a correlation coefficient less than a reference value.

As shown in FIG. 8D , in the case of battery cells having different tendencies among voltage values of a plurality of battery cells, a value of a correlation coefficient less than a reference value (approximately 0.5) may be calculated. At this time, the signal generator 114b may output the second identification signal to the battery cells having different voltage trends, but may also output the identification number of the battery cell.

The signal generating unit 114b obtains standardized scores (Z-scores) based on the information obtained by the information obtaining unit 114a and generates a first identification signal or a second identification signal based on the obtained standardized scores. The first identification signal may be zero (0) or one (1), and the second identification signal may be a signal different from the first identification signal.

The standardized score may include a value between the first score and the second score. For example, the first score may be -3 points, and the second score may be 3 points.

More specifically, when the individual battery cell voltage information V1, V2, and V3 is received, the signal generator 114b generates an average value (μ=Vaverage) of each battery cell voltage based on the received voltage information for each battery cell. is calculated, and a standard deviation (σ, standard deviation) is obtained using the average value of each battery cell voltage.

The signal generator 114b obtains a standardized score (Z-score) based on the standard deviation, voltage, and average value of each battery cell.

Vn is the voltage information of the n battery cells, xi is the voltage of the i-th battery cell among the n battery cells, μ is the average voltage for the n battery cells, and σ is the standard deviation of the voltage for the n battery cells , and Z-score is a standardized score for n battery cells.

The standardized score is a value indicating the degree of dispersion of the voltage values of the battery cells based on the average value of the voltages of the battery cells, and may be obtained as values 0 or more by scoring deviations from the average value of the voltages.

In other words, the standardization score is a value representing the distribution of voltage data of battery cells by calculating the ratio of the deviation value and the standard deviation, which is the difference between the voltage value of each battery cell and the average value of the voltages.

As the standardization score is closer to 0, it means that the voltage value of the battery cell is closer to the average value, and as the standardization score is farther from 0, it means that the voltage value of the battery cell is farther from the average value.

The standardized score is relative information and can be expressed as a value of a random variable for the difference from the average value of the voltage regardless of whether the voltage value of the battery cell is large or small.

As shown in FIG. 8E , when the voltage values of the battery cells are statistically normally distributed, 99.7% of the total voltage data indicates that the standardization score is 3 or less, which is probabilistic for most of the battery cells within 3 times the standard deviation. It means that a voltage value (ie, voltage data) exists.

8F is a graph of voltage changes of a plurality of battery cells, and FIG. 8G is a graph showing normalized scores of the plurality of battery cells.

As shown in FIG. 8G , if the voltage values between the plurality of battery cells have the same tendency and the deviation of the voltage values from other battery cells is as low as about 0.1 V or less, the standardized score is calculated as less than 3, but other battery cells If the deviation of the voltage value from the voltage value increases, the standardized score may be calculated as 3 or more. Here, the standardized score 3 may be a reference standardized score.

The signal generator 114b generates and outputs a first identification signal (eg, 1) for a battery cell having a standardized score of 3 or less, and a second identification signal (eg, 0) for a battery cell having a standardized score exceeding 3 ) is generated and printed.

The signal generator 114b may generate and output first and second identification signals for battery cells based on the correlation coefficient, and generate and output first and second identification signals for battery cells based on the standardized score. and may generate and output the first and second identification signals for the battery cells based on the correlation coefficient and the standardization score.

As such, the signal generating unit 114b may diagnose a failure between adjacent battery cells, between adjacent battery modules, or between adjacent battery racks, based on at least one of a correlation coefficient and a standardization score, and in response to this, a battery for fire prevention It can monitor identification changes of cells, battery modules or battery racks.

The recognition unit 114c receives the first and second identification signals output from the signal generation unit 114b.

When receiving the second identification signal, the recognition unit 114c may receive identification information (eg, may be an identification number) of a battery cell corresponding to the second identification signal together, and the generation time of the second identification signal Alternatively, time information regarding the reception time of the voltage signal corresponding to the second identification signal may be received together.

The recognition unit 114c may accumulate and store the second identification signal received from the signal generator 114b. The recognition unit 114c may store identification information and time information of the battery cell in the storage unit 115 when the second identification signal is accumulated and stored.

The recognition unit 114c recognizes the abnormal state of the battery cell based on the accumulated and stored second identification signal, and recognizes the risk of failure based on the recognition result.

The recognition unit 114c may count the number of times of generation of the second identification signal for each battery cell based on the accumulated and stored second identification signal, and recognize the risk of failure based on the counted number of times of generation of the second identification signal.

The recognition unit 114c may transmit an alarm and cut-off command signal to the control unit 120 in response to recognizing an abnormal state of the battery cell.

As shown in FIGS. 9A and 9B , the recognition unit 114c is positioned in the form of a matrix in which identification information (rack number/module number/cell number) of the battery cell includes the number of times of generation of the second identification signal for each battery cell. Information can be accumulated and managed.

In addition, the accumulated information of the second identification signal may be information normalized based on a probabilistic method, such as a frequency according to an accumulation frequency according to time and a frequency according to the number of occurrences.

The recognition unit 114c diagnoses and prevents battery cell failure by recognizing the risk of failure based on the occurrence repeatability and frequency of the abnormal signal, rather than recognizing the abnormal state of the battery cell by one-time recognition of the second identification signal. can be performed.

At least one component may be added or deleted according to the performance of the components of the monitoring unit illustrated in FIG. 4B . In addition, it will be readily understood by those of ordinary skill in the art that the mutual positions of the components may be changed corresponding to the performance or structure of the system.

Meanwhile, each component illustrated in FIG. 4B means a hardware component such as software and/or a Field Programmable Gate Array (FPGA) and an Application Specific Integrated Circuit (ASIC).

10 is a control flowchart of an energy storage device according to an embodiment.

The energy storage device obtains voltage information corresponding to the voltages of the cells of the battery detected by the voltage detector, and based on the voltages of the plurality of battery cells and the connection relationship between the plurality of battery cells, that is, all batteries based on the parallel connection and the series connection. Voltage information corresponding to the total voltage by the cell is acquired (141).

The energy storage device analyzes the correlation of the battery cells based on the voltage of the battery cells and the total voltage, and calculates a correlation coefficient from a first value (1) to a second value (-1) based on the analyzed correlation. It is obtained as a continuous signal, and the standardized score of the battery cells is analyzed ( 142 ) based on the voltage value, the average value, and the standard deviation of each battery cell.

Here, obtaining the value of the correlation coefficient includes calculating the value of the correlation coefficient using information about the total voltage and voltages of battery cells acquired for a predetermined time.

More specifically, when the total voltage of the battery and the individual battery cell voltage are received, the energy storage device accumulates and stores the received information based on the received time, and the average value of the total voltage accumulated and stored for a predetermined time and the voltage of each battery cell calculates an average value of , obtains covariance using the average of the calculated total voltages and the average value of each battery cell voltage, and obtains a product of standard deviation.

Here, the covariance may be a numerator in Equation (1). And the standard deviation may be the denominator in Equation (1).

식(1)

Formula (1)

rx,y : correlation coefficient of x and y

total voltage information,

voltage information of the i-th battery cell,

Voltage information received for a period of time (n),

σ: standard deviation over a period of time (n), μ: average over a period of time (n)

Equation (1) is an expression for calculating the value of the correlation coefficient, which indicates the degree of correlation between two variables as an exponent.

When the individual battery cell voltage information (V1, V2, V3) is received, the energy storage device calculates an average value (μ=Vaverage) of each battery cell voltage based on the received voltage information for each battery cell, and A standard deviation (σ, standard deviation) is obtained using the average value. Here, the received voltage information may be a voltage value.

The energy storage device acquires a standardized score (Z-score) based on the standard deviation, voltage, and average value for each battery cell.

In the energy storage device, if the voltage values between the plurality of battery cells have the same tendency and the deviation of the voltage values from other battery cells is as low as about 0.1 V or less, the standardization score can be calculated as 3 or less, and If the deviation of the voltage value becomes large, the standardized score can be calculated as more than 3.

The energy storage device generates and outputs a first identification signal (eg, 1) for a battery cell with a standardized score of 3 or less, and generates a second identification signal (eg, 0) for a battery cell with a standardized score of 3 or less to output

The energy storage device obtains a value of a correlation coefficient for each of the plurality of battery cells, generates an identification signal 143 based on the obtained correlation coefficient values and a reference value, and accumulates and stores the generated identification signal. The energy storage device may store the identification signal together with identification information of the battery cell.

The energy storage device obtains a standardized score for each of the plurality of battery cells, generates an identification signal based on the obtained standardized score and the reference standardized score (143), and accumulates and stores the generated identification signal. The energy storage device may store the identification signal together with identification information of the battery cell. Here, the reference standardized score may be three.

More specifically, the energy storage device compares values of correlation coefficients obtained for each battery cell with a reference value, respectively, and when the value of the correlation coefficient obtained is equal to or greater than the reference value, generates a first identification signal, and If the value is less than the reference value, a second identification signal is generated.

The energy storage device compares the standardized score and the standard standardized score obtained for each battery cell, respectively, generates a first identification signal if the obtained standardized score is less than or equal to the reference standardized score, and generates a second identification signal if the obtained standardized score exceeds the standard standardized score 2 Generate an identification signal.

Here, the first identification signal may be zero (0), and the second identification signal may be one (1). In addition, when the first identification signal is one (1), the second identification signal may be zero (0).

The energy storage device may determine whether each battery cell has failed by calculating a standardized score of the battery cells and relatively evaluating the voltage deviation of the battery cells.

In addition, the energy storage device may determine whether the operating states of the battery cells are the same or similar to each other by calculating a correlation coefficient between the battery cells. That is, the energy storage device may determine whether the battery cells operate with the same tendency.

The energy storage device determines whether a second identification signal is present among the generated identification signals (144), and when it is determined that the second identification signal exists, in response to the generation of the second identification signal, the battery associated with the generation of the second identification signal The identification information of the cell is checked (145), and the checked identification information of the battery cell and the second identification signal are stored together.

The energy storage device determines whether each battery cell has an abnormal state and a risk of failure based on the accumulated and stored identification signal.

More specifically, the energy storage device may identify a battery cell in which the second identification signal exists for each battery cell, and recognize the battery cell in which the second identification signal exists as a battery cell in an abnormal state.

It is also possible for the energy storage device to determine ( 146 ) that the failure risk of the battery cell is equal to or greater than the reference risk level based on the accumulated number of storage of the second identification signal for each battery cell.

That is, the energy storage device checks the accumulated number of storage of the second identification signal for each battery cell, and if the accumulated number of storage is less than or equal to the reference number of times, determines that the risk of the battery cell is less than the reference risk, and outputs warning information about the warning (147). .

On the other hand, the energy storage device determines that the risk level of the battery cell is greater than or equal to the reference risk level when the checked accumulated number of storage times exceeds the reference number, and blocks the operation of the battery system related to charging and discharging the battery (148).

In addition, the energy storage device may determine the risk of failure according to the cumulative frequency of the second identification signal.

Meanwhile, the disclosed embodiments may be implemented in the form of a recording medium storing instructions executable by a computer. Instructions may be stored in the form of program code, and when executed by a processor, a program module may be created to perform the operations of the disclosed embodiments. The recording medium may be implemented as a computer-readable recording medium.

The computer-readable recording medium includes any type of recording medium in which instructions readable by the computer are stored. For example, there may be a read only memory (ROM), a random access memory (RAM), a magnetic tape, a magnetic disk, a flash memory, an optical data storage device, and the like.

As described above, the disclosed embodiments have been described with reference to the accompanying drawings. Those of ordinary skill in the art to which the present invention pertains, without changing the technical spirit or essential features of the present invention, may It will be understood that the present invention may be practiced. The disclosed embodiments are illustrative and should not be construed as limiting.

1: energy storage device 2: vehicle
100: battery 111: voltage detection unit
112: current detection unit 113: temperature detection unit
114: monitoring unit 115: storage unit
116: communication department

Claims (22)

a plurality of battery cells connected in at least one of a series connection and a parallel connection;
a detection unit configured to detect electrical signals of the plurality of battery cells;
Obtaining an electrical signal for each of the plurality of battery cells and a value of a correlation coefficient corresponding to a correlation obtained based on the electrical signal, and an electrical signal of the plurality of battery cells based on the values of the correlation coefficient and a reference value a monitoring unit that generates an identification signal corresponding to ; and
and a storage unit for storing the identification signal generated by the monitoring unit for each battery cell,
The monitoring unit may be configured to recognize a risk of failure of a battery cell based on the number of identification signals for each battery cell stored in the storage unit. According to claim 1, wherein the detection unit,
a current detection unit detecting a current of each battery cell;
and at least one of a voltage detector configured to detect a voltage of each of the battery cells. 3. The method of claim 2,
Further comprising a temperature detection unit for detecting the temperature of at least one battery cell,
The monitoring unit acquires at least one of a charge state, a lifespan state, an internal resistance, and a capacity change corresponding to a change in voltage of the battery based on the current, voltage and temperature of each battery cell, A battery management apparatus for obtaining a value of a correlation coefficient between the plurality of battery cells based on at least one of a state internal resistance and a capacity change corresponding to a voltage change. The method of claim 1,
The electrical signal includes a voltage signal,
The monitoring unit obtains voltages of the plurality of battery cells based on voltage signals of each of the plurality of battery cells, obtains a total voltage based on voltages of the plurality of battery cells, and obtains a total voltage of each battery for the total voltage. A battery management device for obtaining a value of a correlation coefficient of a cell. The method of claim 4, wherein the monitoring unit,
If the obtained correlation coefficient value is greater than or equal to a reference value, generate a first identification signal, if the obtained correlation coefficient value is less than a reference value, generate a second identification signal, and store the second identification signal in the storage unit a battery management device. According to claim 5, wherein the monitoring unit,
A battery management device for recognizing a risk of failure of a battery cell based on the number of second identification signals for each battery cell stored in the storage unit. According to claim 1, wherein the monitoring unit,
A battery management apparatus for obtaining a value of a correlation coefficient using electrical signals of a plurality of battery cells detected for a predetermined time. The method of claim 6, wherein the monitoring unit,
A battery management device for determining a repetition degree and frequency of the number of second identification signals for each battery cell stored in the storage unit. a battery including a plurality of battery cells connected in at least one of a series connection and a parallel connection;
a detection unit configured to detect electrical signals of the plurality of battery cells;
Obtaining an electrical signal for each of the plurality of battery cells and a value of a correlation coefficient corresponding to a correlation obtained based on the electrical signal, and an electrical signal of the plurality of battery cells based on the values of the correlation coefficient and a reference value a battery management device for generating and storing an identification signal corresponding to , and monitoring a risk of failure of a battery cell based on the number of stored identification signals for each battery cell;
a controller configured to control output of warning information based on the risk of failure of the battery cells, and to block charging and discharging of the plurality of battery cells; and
and a display unit configured to display the warning information based on a control command of the control unit. 10. The method of claim 9, wherein the detection unit,
a current detection unit detecting a current of each battery cell;
and at least one of a voltage detector configured to detect a voltage of each of the battery cells. 11. The method of claim 10,
Further comprising a temperature detection unit for detecting the temperature of at least one battery cell,
The battery management device obtains at least one of a state of charge, a lifespan, and a change in capacity corresponding to a change in internal resistance and voltage of the battery based on the current, voltage, and temperature of each of the battery cells, and the state of charge of the battery , an energy storage device to obtain a correlation between the plurality of battery cells based on at least one of a lifespan state, an internal resistance, and a capacity change corresponding to a voltage change. 10. The method of claim 9,
The electrical signal includes a voltage signal,
The battery management apparatus obtains voltages of the plurality of battery cells based on voltage signals of each of the plurality of battery cells, obtains a total voltage based on voltages of the plurality of battery cells, and An energy storage device for obtaining the value of the correlation coefficient of each battery cell. 13. The method of claim 12,
further comprising a storage unit,
The battery management device generates a first identification signal when the value of the obtained correlation coefficient is greater than or equal to a reference value, and generates a second identification signal when the value of the obtained correlation coefficient is less than a reference value, and generates the second identification signal An energy storage device to be stored in the storage unit. The method of claim 13, wherein the battery management device,
An energy storage device for recognizing a risk of failure of a battery cell based on the number of second identification signals for each battery cell stored in the storage unit. 15. The method of claim 14, wherein the battery management device,
An energy storage device for determining a repetition degree and frequency of the number of second identification signals for each battery cell stored in the storage unit. 10. The method of claim 9, wherein the battery management device,
An energy storage device for managing a battery module in which the plurality of battery cells are connected in series and in parallel. 10. The method of claim 9,
The battery management device manages a battery rack comprising a plurality of battery modules connected in series and in parallel,
Each battery module is an energy storage device including battery cells connected in series and parallel. a battery including a plurality of battery cells connected in at least one of a series connection and a parallel connection;
a detection unit configured to detect electrical signals of the plurality of battery cells;
Obtaining an electrical signal for each of the plurality of battery cells and a value of a correlation coefficient corresponding to a correlation obtained based on the electrical signal, and based on a voltage value corresponding to the electrical signal for each of the plurality of battery cells obtaining an average value and a standard deviation, and obtaining a standardized score of each of the battery cells based on the voltage value, the average value, and the standard deviation of each battery cell; a battery management device for generating an identification signal corresponding to each of the battery cells based on the battery and monitoring a risk of failure of each of the battery cells based on the identification signal corresponding to each of the battery cells;
a controller configured to control output of warning information based on the risk of failure of each of the battery cells, and to block charging and discharging of each of the battery cells; and
and a display unit configured to display the warning information based on a control command of the control unit. The method of claim 18, wherein the detection unit,
a current detection unit detecting a current of each battery cell; and
and at least one of a voltage detector configured to detect a voltage of each of the battery cells. 19. The method of claim 18,
The electrical signal includes a voltage signal,
The battery management apparatus obtains voltages of the plurality of battery cells based on voltage signals of each of the plurality of battery cells, obtains a total voltage based on voltages of the plurality of battery cells, and An energy storage device for obtaining the value of the correlation coefficient of each battery cell. 19. The method of claim 18,
The battery management device generates a first identification signal when the value of the obtained correlation coefficient is greater than or equal to a reference value, and generates a second identification signal when the value of the obtained correlation coefficient is less than a reference value, and the obtained standardized score is An energy storage device for generating the first identification signal when the standardized score is less than or equal to a reference standardized score, and generates the second identification signal when the obtained standardized score exceeds the reference standardized score. The method of claim 21, wherein the battery management device,
An energy storage device for recognizing a risk of failure of a battery cell based on the number of second identification signals of each of the battery cells.

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