Battery system for preventing abnormal output voltage and control method thereof

Abstract

A system for preventing abnormal voltage at the output terminal of a battery includes a battery management system (BMS), which includes: multiple voltage sensors for detecting a first voltage of multiple battery cells; a relay switch for applying a first voltage to an electrical device according to a first control signal from the BMS; an automatic cut-off switch for cutting off power applied from the multiple battery cells according to a second control signal from the BMS; a high-voltage interlock switch connected to the automatic cut-off switch and used to operate at a second voltage that reaches or exceeds a preset voltage; an active voltage switch for operating at a third voltage transmitted through the automatic cut-off switch to control the relay switch; and a controller for providing a cut-off control signal to the relay switch in response to detecting a voltage higher than a threshold voltage in the first voltage through the voltage sensor.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2020-0091144, filed on Jul. 22, 2020, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates to a battery system with a function of preventing abnormal voltage at an output terminal, and more particularly to a battery system capable of preventing abnormal voltage from occurring at an output terminal and thus protecting the output terminal when a battery cell of an automobile battery system is short-circuited. Background Art

[0004] like Figure 1 As shown, when a battery short circuit occurs in an existing battery system, the method for disconnecting the closed circuit connection is to mechanically disconnect the internal high-voltage fuses provided between the battery cells, thereby cutting off the connection in the battery.

[0005] Alternatively, there is a method in which a battery management system (BMS) that manages a battery system controls an external relay switch to electrically deactivate an output terminal of a battery cell.

[0006] For this reason, Figure 2 As shown, the existing BMS system 10 includes: a voltage sensor 11, which is used to detect whether the voltage applied from the battery cell 20 reaches or is greater than a predetermined voltage; a central processing unit (CPU) 12, which provides a control signal to the relay switch 40 to cut off the voltage applied from the battery cell 20 when the voltage value detected by the voltage sensor 11 reaches or is greater than a preset value; and an organic photodiode integrated circuit (Organic Photodiode integrated circuit, OPD IC) 13, which can perform an operation to disconnect the relay switch 40 through the high-voltage switch 14 when a high voltage is applied from the battery cell 20.

[0007] That is, when an overvoltage applied from the battery cell 20 is detected by the voltage sensor 11 , the CPU 12 in the BMS 10 outputs a control signal and transmits the control signal to the relay switch 40 to cut off the connection of the power source to the battery cell 20 .

[0008] In addition, there is another method. In the state where the CPU 12 in the BMS 10 fails, when a voltage reaching or greater than a preset value is applied inside the BMS 10, the OPD IC 13 performs an operation to disconnect the relay switch 40 through the high-voltage switch 14, thereby electrically deactivating the output terminal of the battery cell 20.

[0009] However, in the existing battery system in which the relay switch is disconnected by fuse disconnection or CPU control, when a high external current is applied, even when the relay switch is disconnected by the CPU, an unexpected non-ideal closed circuit (closed loop) is formed in the internal circuit of the BMS, so there is a problem of the battery output terminal voltage being activated. Summary of the invention

[0010] The present disclosure aims to solve the above-mentioned problems and provide a battery system with the function of preventing abnormal voltage at the output end, which can be controlled to prevent the generation of a closed loop in the battery management system (BMS) due to BMS failure and the nature of increased power and protection circuits of electronic components of the battery system, and can prevent the output end of the battery cell from being electrically activated in advance.

[0011] It should be noted that the purpose of the present disclosure is not limited to the above-mentioned purpose, and other purposes of the present disclosure will be obvious to those skilled in the art through the following description.

[0012] According to one aspect of the present disclosure, there is provided a battery system for preventing abnormal voltage at the output end, comprising: a plurality of voltage sensors for respectively detecting first voltages of a plurality of battery cells; a relay switch for applying a first voltage to an electrical device according to a first control signal from a BMS; an automatic cut-off switch for cutting off power applied from a plurality of battery cells according to a second control signal from the BMS; a high-voltage interlock switch connected to the automatic cut-off switch and for operating at a second voltage reaching or exceeding a preset voltage; an active voltage switch for operating at a third voltage transmitted through the automatic cut-off switch to control the relay switch; and a controller for providing a cut-off control signal to the relay switch in response to detecting a voltage higher than a threshold voltage in the first voltage through the voltage sensor.

[0013] When the relay switch does not perform a cutoff in response to receiving a cutoff control signal from the controller, the controller may output a third control signal to an automatic cutoff switch to open the relay switch through an active voltage switch.

[0014] When a third control signal is output to turn off the relay switch and activation of output terminals of the plurality of battery cells is detected by the voltage sensor, the controller may output a fourth control signal to the automatic cut-off switch to turn off the automatic cut-off switch.

[0015] According to another aspect of the present disclosure, a method for controlling a battery system to prevent abnormal voltage at an output terminal is provided, comprising: determining whether a voltage reaching or exceeding a preset voltage is applied from a battery cell; when determining that a voltage reaching or exceeding the preset voltage is applied from the battery cell, a controller of a battery management system (BMS) determines whether a relay switch is controllable; when determining that the relay switch is uncontrollable, the controller switches an automatic cut-off switch to on to apply the voltage applied from the battery cell to an active voltage switch and a high-voltage interlock switch; and when determining that the voltage applied from the battery cell reaches or is less than the preset voltage, controlling the active voltage switch to disconnect the relay switch.

[0016] The control method may further include, when it is determined that the voltage applied from the battery cell exceeds the preset voltage, operating a high voltage interlock switch that operates only at a preset voltage or higher to control the relay switch to be opened.

[0017] The control method further includes, when it is determined that the relay switch is controllable by the controller, the controller directly controls the relay switch to be disconnected.

[0018] According to another aspect of the present disclosure, a method for controlling a battery system to prevent abnormal voltage at the output end is provided, comprising: a controller in the battery system detects whether a voltage reaching or exceeding a preset value is applied from a battery cell through a voltage sensor; when it is detected that a voltage reaching or exceeding the preset value is applied from the battery cell, the controller provides a first control signal to a relay switch externally connected to the battery system to block the connection between the relay switch and the battery cell; in a state in which the connection between the relay switch and the battery cell is blocked, detecting whether any voltage is applied to the battery cell through the voltage sensor; and when any voltage applied from the battery cell is detected, outputting a second control signal for blocking the connection with an automatic cut-off switch in a battery management system (BMS) connected to the battery cell to cut off the voltage applied from the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other objects, features and advantages of the present disclosure will become more apparent to those skilled in the art by describing in detail exemplary embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0020] Figure 1 is a functional block diagram of an existing battery system;

[0021] Figure 2 Is used to describe Figure 1 Functional block diagram of the detailed configuration of the battery management system (BMS);

[0022] Figure 3is a functional block diagram for describing a battery system having a function of preventing abnormal voltage at an output terminal according to an embodiment of the present disclosure;

[0023] Figure 4 is a flowchart for describing a control method of a battery system having a function of preventing abnormal voltage at an output terminal according to an embodiment of the present disclosure; and

[0024] Figure 5 is a flowchart for describing a control method of a battery system having a function of preventing abnormal voltage at an output terminal according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0025] From the detailed description of the embodiments in conjunction with the accompanying drawings below, its advantages, features and embodiments will be more clear. However, the present disclosure can be implemented in many different forms and should not be interpreted as being limited to the embodiments described herein. Moreover, these embodiments are provided so that the present disclosure will be detailed and complete, and the scope of the present disclosure is fully conveyed to those skilled in the art to which the present disclosure belongs. Moreover, the present disclosure is limited only by the scope of the claims. At the same time, the terms used herein are for the purpose of describing the embodiments, not for limiting the present disclosure. As used herein, the singular form also includes the plural form, unless the context clearly indicates otherwise. It should be noted that the terms "comprising" and / or "including" used herein do not exclude the presence or addition of one or more other components, steps, operations and / or elements other than the components, steps, operations and / or elements.

[0026] Figure 3 is a functional block diagram for describing a battery system having a function of preventing abnormal voltage at an output terminal according to an embodiment of the present disclosure.

[0027] like Figure 3 As shown, a battery system having a function of preventing abnormal voltage at the output terminal according to an embodiment of the present disclosure includes a voltage sensor 110 , an automatic cut-off switch 120 , a high voltage interlock switch 130 , an active voltage switch 140 and a controller 150 .

[0028] The plurality of voltage sensors 110 detect voltages of the plurality of battery cells 20 .

[0029] After the controller 150 outputs a control signal for disconnecting the relay switch 40, when the voltage sensor 110 detects the voltage output of the battery unit 20, the automatic cut-off switch 120 cuts off the power supplied from the battery 21 according to the control signal output by the controller 150. In one embodiment of the present disclosure, a switch element may be used as the automatic cut-off switch 120, but the present disclosure is not limited thereto.

[0030] The high voltage interlock switch 130 is connected to the automatic cut-off switch 120, and when a voltage reaching or greater than a preset voltage is applied from the battery 21 through the automatic cut-off switch 120, the high voltage interlock switch 130 operates to control the relay switch 40 to be disconnected through the high voltage switch.

[0031] For electrical equipment, the active voltage switch 140 operates at a voltage of 12V, which is transmitted through the automatic cutoff switch 120 to control the relay switch 40 through the high voltage switch. In this embodiment, a switch whose setting of the driving voltage value of the high voltage interlock switch 130 is changed can be used as the active voltage switch 140.

[0032] When the voltage sensor 110 detects a high voltage output from the battery unit 20 , the controller 150 issues a cutoff control signal to the relay switch 40 .

[0033] According to one embodiment of the present disclosure, when an overvoltage is output from the battery unit 20 , there is an effect of being able to directly control the relay switch 40 to block the overvoltage.

[0034] In addition, in one embodiment of the present disclosure, the relay switch 40 cannot be directly controlled by the controller 150, and the active voltage switch 140 can be driven using the voltage applied by the battery 21, and the automatic cut-off switch 120 can be controlled to disconnect the relay switch 40 through the driven active voltage switch 140.

[0035] According to one embodiment of the present disclosure, even when the relay switch 40 is not controlled by the controller 150 of the battery management system (BMS), it has the effect of being able to control the relay switch 40 without using the high-voltage interlock switch 130 that requires a voltage to reach or exceed a threshold, thereby blocking the application of high voltage.

[0036] The above-mentioned effects of the present disclosure can solve the problem that when the existing method of controlling the relay switch 40 by using the high-voltage interlock switch 130 is adopted when the controller 150 is available, the high-voltage interlock switch 130 operates at a certain voltage or higher, resulting in non-ideal results due to overvoltage.

[0037] In addition, according to the present disclosure, since it is difficult to anticipate that a certain voltage or higher voltage will be applied to the BMS, especially during an external short circuit, it has the effect of being able to switch the active voltage switch 140 using the input voltage (12V) applied from the battery 21 and thereby disconnect the relay switch 40 connected to the electrical device, thereby electrically deactivating the output terminal of the battery cell 20.

[0038] In addition, when the controller 150 confirms through the voltage sensor 110 that the voltage at the output end of the battery cell 20 is activated even when the relay switch 40 is controlled to be in the disconnected state, the controller 150 switches the automatic cut-off switch 120 to the disconnected state to cut off the power applied from the battery 21 to the inside of the BMS, thereby having the effect of preventing a closed circuit from being formed inside the BMS and controlling the electrical deactivation of the output end of the battery cell 20.

[0039] That is, in the existing battery system, when the battery cell 20 (fuse) is inserted therebetween, it is a common phenomenon that the battery cell 20 is short-circuited when the BMS detects the voltage. However, occasionally, the internal circuit of the BMS is damaged or the relay switch 40 is fused due to a large external current, so that a closed circuit may be formed in the BMS due to a non-ideal phenomenon.

[0040] As described above, when a closed circuit is formed inside the BMS, the output terminal of the battery cell 20 may be electrically activated. However, in one embodiment of the present invention, in order to prevent the closed circuit from being formed inside the BMS, the 12V power supply is cut off in advance, thereby having the effect of preventing the closed circuit from being formed inside the BMS, thereby preventing the output terminal of the battery cell 20 from being electrically activated.

[0041] Reference Figure 4 A control method of a battery system having a function of preventing abnormal voltage at an output terminal according to another embodiment of the present disclosure is described.

[0042] When the voltage sensor 110 detects that a voltage reaching or exceeding a preset voltage is applied from the battery cell 20 , the controller 150 of the BMS determines whether the relay switch 40 is controllable ( S110 ).

[0043] When the relay switch 40 is not controllable in the judgment operation (No of S110 ), the controller 150 turns on the automatic cutoff switch 120 to allow the voltage applied from the battery unit 20 to be applied to the active voltage switch 140 and the high voltage interlock switch 130 ( S120 ).

[0044] Then, when the voltage applied from the battery cell 20 is equal to or less than the preset voltage (No of S130), the active voltage switch 140 is driven to control the relay switch 40 to be disconnected (S140), and the active voltage switch 140 is driven by the voltage applied by the battery 21 through the automatic cut-off switch 120.

[0045] According to one embodiment of the present disclosure, since it is difficult to anticipate the effect above a certain battery voltage when an external short circuit occurs, the following device is used to disconnect the relay switch 40. When an input voltage (12V) is applied from the battery 21, the automatic cut-off switch 120 is operated to control the high voltage switch through the active voltage switch 140. Therefore, the relay switch 40 existing outside the BMS can be disconnected to electrically deactivate the output terminal of the battery unit 20.

[0046] Otherwise, when the output voltage of the battery unit 20 exceeds the preset voltage (Yes of S130), the high voltage interlock switch 130 that can operate only above the preset voltage operates to control the relay switch 40 to be turned off through the high voltage switch (S150).

[0047] On the other hand, when the relay switch 40 is controllable by the controller 150 in the judging operation (“Yes” of S110 ), the controller 150 directly controls the relay switch 40 to be turned off ( S160 ).

[0048] As described above, according to one embodiment of the present disclosure, in addition to whether the relay switch 40 can be controlled by the controller of the BMS, the connection between the relay switch 40 and the battery cell 20 can be disconnected by controlling the relay switch 40 according to the applied voltage, thereby having the effect of electrically deactivating the output terminal of the battery cell 20.

[0049] Figure 5 is a flowchart for describing a control method of a battery system having a function of preventing abnormal voltage at an output terminal according to another embodiment of the present disclosure.

[0050] In the following, reference will be made to Figure 5 A control method of a battery system having a function of preventing abnormal voltage at an output terminal according to another embodiment of the present disclosure is described.

[0051] The controller 150 in the BMS 100 determines whether a voltage reaching or exceeding a preset value is applied from the battery cell 20 using the voltage sensor 110 ( S210 ).

[0052] In the judgment operation (S210), when a voltage equal to or greater than a preset value is detected by the voltage sensor 110 (Yes), a control signal is provided to the externally provided relay switch 40 to prevent the voltage from being applied from the battery cell 20 (S220). Therefore, the voltage applied from the battery cell 20 is cut off and not applied to the electrical device 50.

[0053] Thereafter, in a state where the connection with the battery cell 20 is blocked, it is detected by the voltage sensor 110 whether any voltage is applied from the battery cell 20 ( S230 ).

[0054] When it is detected by the voltage sensor 110 that any voltage is applied from the battery cell 20 in a state where the connection with the battery cell 20 is blocked ("Yes" in S230), in order to cut off the voltage applied from the battery 21 to drive the BMS 100, a control signal is provided to the automatic cut-off switch 120 provided inside the BMS 100 and connected to the battery 21 to disconnect the automatic cut-off switch 120 (S240).

[0055] Therefore, according to one embodiment of the present disclosure, the voltage applied from the battery 21 is cut off so as not to be applied to the BMS, which has an effect of being able to prevent a closed circuit from being formed inside the BMS.

[0056] As described above, when a closed circuit is formed inside the BMS and a voltage is formed at the output end of the battery cell 20, in the case of the existing battery system, the output end of the battery cell 20 can be electrically activated even after a short circuit is formed. However, in one embodiment of the present disclosure, in order to prevent the closed circuit from being formed inside the BMS, the 12V power supply applied from the battery 21 is cut off in advance, thereby having the effect of preventing the output end of the battery cell 20 from being electrically activated.

[0057] For reference, the components according to the embodiments of the present disclosure may be implemented in the form of hardware or software such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), and may perform predetermined roles.

[0058] However, the “component” is not limited to software or hardware, and each component may be stored in an addressable storage medium or replicated in one or more processors.

[0059] Thus, by way of example, components include components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, properties, procedures, subroutines, program code segments, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables.

[0060] The components and the functionality provided within the components may be combined into a smaller number of components or may be further separated into additional components.

[0061] In this case, it should be understood that each block of the flowchart and the combination of the flowcharts can be executed by computer program instructions. These computer program instructions can be included in a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that the instructions executed by the processor of the computer or other programmable data processing device generate components for performing the functions described in one or more flowchart blocks. These computer program instructions can use a computer or other programmable data processing device to implement functions in a specific manner, and can also be stored in a computer-readable memory, so that the instructions using a computer or stored in a computer-readable memory can generate an operation text, including an instruction portion for performing the functions described in one or more flowchart blocks. Since the computer program instructions can also be installed in a computer or other programmable data processing device, the instructions for performing a series of operations on the computer or other programmable data processing device to generate a computer executable program, and then operating the computer or other programmable data processing device, can provide operations for performing the functions described in one or more flowchart blocks.

[0062] In addition, each block may represent a portion of a module, segment, or code, which includes one or more executable instructions for performing one or more specified logical functions. It should also be noted that in some alternative embodiments, the functions mentioned in the blocks may also be out of order. For example, two blocks shown in succession may be executed substantially simultaneously, or in some cases, the two blocks may be executed in reverse order according to the corresponding functions.

[0063] In this case, the term "~part" used in the embodiment refers to a software or hardware component such as an FPGA or an application specific integrated circuit (ASIC), and performs a predetermined role. However, the meaning of the term "~part" is not limited to software or hardware. "~part" can be formed and stored in an addressable storage medium or copy one or more processors. Therefore, as an example, "~part" includes components such as software components, object-oriented software components, class components and task components, as well as processes, functions, attributes, procedures, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays and variables. The functions provided in components and "~parts" can be combined into a smaller number of components and "~parts", or can be further divided into additional components and "~parts". In addition, components and "~parts" can be implemented as one or more CPUs in a copy device or a secure multimedia card.

[0064] According to the present disclosure, when a battery cell of a battery system is short-circuited, the battery cell in an incomplete state is mainly blocked by a high-voltage fuse, which has the effect of providing electrical deactivation of the battery cell even when the relay switch is blown and the voltage of the battery cell is activated.

[0065] Furthermore, according to the present disclosure, even when an unexpected closed circuit is formed according to the increase in functions of a battery management system (BMS), there is an effect of being able to deactivate a voltage at an output terminal of the BMS.

[0066] Each step included in the above learning method can be implemented as a software module, a hardware module or a combination thereof executed by a computing device.

[0067] Furthermore, the elements for executing each step may be implemented as first to second operation logics of the processor, respectively.

[0068] The software modules may be stored in RAM, flash memory, ROM, erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, hard disk, an attachable / removable disk, or a storage medium (i.e., memory and / or storage), such as a CD-ROM.

[0069] An exemplary storage medium may be coupled to the processor, and the processor may read information from the storage medium and write information to the storage medium. In other embodiments, the storage medium may be provided integrally with the processor.

[0070] The processor and storage medium may be provided in an application specific integrated circuit (ASIC). The ASIC may be provided in a user terminal. In other embodiments, the processor and storage medium may be provided as separate components in a user terminal.

[0071] For the sake of clarity, the exemplary method according to the embodiment may be represented as a series of operation steps, but such steps do not limit the order in which the operations are performed. Depending on the circumstances, the steps may be performed simultaneously or in different orders.

[0072] To implement the method according to the embodiment, the disclosed steps may further include another step, include steps other than some steps, or include another additional step other than some steps.

[0073] The various embodiments of the present disclosure do not list all available combinations but merely describe representative aspects of the present disclosure, and the description of the various embodiments may be applied independently or may be applied by a combination of two or more.

[0074] In addition, various embodiments of the present disclosure may be implemented in hardware, firmware, software, or a combination thereof. Where various embodiments of the present disclosure are implemented in hardware, various embodiments of the present disclosure may be implemented in one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), general purpose processors, controllers, microcontrollers, or microprocessors.

[0075] The scope of the present disclosure may include software or machine-executable instructions (e.g., an operating system (OS), applications, firmware, programs, etc.) that enable operations according to the methods in various embodiments to be performed in a device, a computer, and a non-transitory computer-readable medium that can be executed in a device or computer storing the software or instructions.

[0076] A number of exemplary embodiments have been described above. However, it should be understood that various modifications may be made. For example, suitable results may be obtained if the described techniques and / or components in the described systems, architectures, devices, or circuits are combined in different ways and / or replaced or supplemented by other components or their equivalents. Therefore, other implementations are also within the scope of the claims.

[0077] Although the configuration of the present disclosure has been described in detail with reference to the accompanying drawings, this is merely an example, and modifications and substitutions within the technical spirit of the present disclosure may be thought of by those skilled in the art. Therefore, the protection scope of the present invention should not be limited to the above-described embodiments, but should be defined by the description of the claims.

Claims

1. A battery system for preventing abnormal voltage at an output terminal, the battery system comprising a battery management system BMS, which comprises: A plurality of voltage sensors, used for respectively detecting first voltages of a plurality of battery cells; a relay switch, configured to apply the first voltage to the electrical device according to a first control signal from the BMS; an automatic cut-off switch for cutting off power applied from the plurality of battery cells according to a second control signal from the BMS; a high voltage interlock switch connected to the automatic cut-off switch and configured to operate at a second voltage that is equal to or greater than a preset voltage; an active voltage switch for operating at a third voltage transmitted through the automatic disconnect switch to control the relay switch; as well as A controller is configured to provide a cutoff control signal to the relay switch in response to detecting, by the voltage sensor, a voltage higher than a threshold voltage among the first voltages.

2. The battery system according to claim 1, wherein: When the relay switch does not perform a cutoff in response to receiving a cutoff control signal from the controller, the controller is configured to output a third control signal to the automatic cutoff switch to open the relay switch through the active voltage switch.

3. The battery system according to claim 2, wherein: When the third control signal is output to turn off the relay switch and activation of the output terminals of the plurality of battery cells is detected by the voltage sensor, the controller is configured to output a fourth control signal to the automatic cut-off switch to turn off the automatic cut-off switch.

4. A method for controlling a battery system to prevent abnormal voltage at an output terminal, comprising: determining whether a voltage reaching or exceeding a preset voltage is applied from the battery cell; When it is determined that a voltage reaching or exceeding the preset voltage is applied from the battery cell, the controller of the battery management system BMS determines whether the relay switch is controllable; When it is determined that the relay switch is uncontrollable, the controller switches the automatic cut-off switch to on to apply the voltage applied from the battery unit to the active voltage switch and the high voltage interlock switch; as well as When it is determined that the voltage applied from the battery cell is less than the preset voltage, the active voltage switch is controlled to turn off the relay switch.

5. The method of claim 4, further comprising: When it is determined that the voltage applied from the battery cell exceeds the preset voltage, the high voltage interlock switch that operates only at the preset voltage or higher is operated to control the relay switch to be opened.

6. The method of claim 4, further comprising: When it is determined that the relay switch is controllable by the controller, the controller directly controls the relay switch to be turned off.

7. A method for controlling a battery system to prevent abnormal voltage at an output terminal, comprising: The controller in the battery system detects, through a voltage sensor, whether a voltage reaching or exceeding a preset value is applied from the battery cell; When it is detected that a voltage reaching or exceeding the preset value is applied from the battery cell, the controller provides a first control signal to a relay switch externally connected to the battery system to block the connection between the relay switch and the battery cell; In a state where the connection between the relay switch and the battery cell is blocked according to the first control signal, detecting by the voltage sensor whether any voltage is applied to the battery cell; as well as When any of the voltages applied by the battery cell is detected, a second control signal is output for blocking a connection with an automatic cut-off switch in a battery management system BMS connected to the battery cell to cut off the voltage applied from the battery cell.

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