KR20190106484A - Apparatus for preventing over discharge in non-rechargeble lithium batteries - Google Patents

Abstract

The present invention relates to an over discharge blocking device. According to an aspect of the present invention, a residual capacity of a unit battery is predicted from a voltage difference across both ends of a resistor by using current integration. The present invention determines whether an initial voltage delay phenomenon is solved in accordance with the predicted residual capacity, detects output voltage of the unit battery when the initial voltage delay phenomenon is solved, turns a switch unit off when the detected output voltage reaches termination voltage so as to improve a response speed of a mechanical determination method of unconditionally waiting by considering a unique initial voltage delay of an existing primary lithium unit battery, thereby effectively preventing an over discharge occurrence and an accident related to bursting and explosion caused by the same.

Description

Low-cost over-discharge blocking device for primary lithium battery {APPARATUS FOR PREVENTING OVER DISCHARGE IN NON-RECHARGEBLE LITHIUM BATTERIES}

The present application relates to an over-discharge blocking device.

In the case of a unit battery, for example, a primary lithium unit battery, there is a problem in that overdischarge occurs due to excessive use of a user and a rupture / explosion accident occurs. However, due to the low cost of production and sales, the primary lithium unit battery does not apply or discharge the over-discharge blocking device for securing stability, the existing over-discharge blocking device has a number of problems.

1 and 2 is a view showing a conventional over-discharge blocking device by way of example. 1 is a view showing a conventional over-discharge blocking device applied to the four series battery unit, Figure 2 is a view showing a conventional over-discharge blocking device applied to one series unit battery.

FIG. 3 is a diagram illustrating discharge characteristics of sections of a primary lithium unit battery. FIG. Section a of FIG. 3 is an initial voltage delay phenomenon section, section b is a normal discharge section, section c is a termination section which is rapidly over discharged after the termination voltage.

1 to 3, the conventional over-discharge blocking device considers an initial voltage delay phenomenon, which is a unique characteristic of the primary lithium unit battery, and cut-off voltage, not an electronic circuit operation concept. Or end voltage). In other words, since the conventional over-discharge blocking device is designed without distinguishing sections a, b, and c of FIG. 3, the standby time considering the initial voltage delay phenomenon is applied unconditionally. However, the mechanical judgment method (waiting for a certain time unconditionally) (using a FET device or IC device) has a problem that the over-discharge blocking device does not operate within an appropriate reaction rate when a rupture / explosion accident occurs due to over-discharge of a unit cell This leads to a second safety accident.

The present application predicts the remaining capacity of the unit cell based on the voltage difference measured by the voltage difference measuring unit, determines whether to monitor the output voltage of the unit cell, and selectively operates the switch unit according to the output voltage of the unit battery monitored The present invention provides an over-discharge blocking device capable of effectively preventing over-discharge occurrence and rupture / explosion caused by excessive use of a unit cell.

The present application includes a circuit unit for electrically connecting a unit cell and a load to supply power to a load, a voltage difference measuring unit for measuring a voltage difference across both ends of the resistor, and including a resistor connected in series with the load; Measured by a switch part and a voltage difference measuring part arranged to operate in (On) / off (Off), to switch the circuit part to the closed circuit when on, and to switch the closed circuit to the open circuit when off. A control unit for estimating the remaining capacity of the unit cell based on the estimated voltage difference, and comparing the predicted remaining capacity of the unit cell with the reference capacity to determine whether to resolve the initial voltage delay phenomenon and to monitor whether the unit cell output voltage is monitored. I provide a blocking device.

In addition, the present application includes a circuit unit for electrically connecting the unit cell and the load so as to supply power to the load, a voltage difference measuring unit for measuring the voltage difference across the resistor, including a resistor connected in series with the load; The switch unit and the unit cell are arranged to operate on / off, to turn the circuit into a closed circuit when on, and to switch the closed circuit into an open circuit when off. Predicting the remaining capacity of the unit cell using the zero mode, current integration to store the voltage value as a correction value and initializing the over-discharge blocking device, and determining whether to solve the initial voltage delay phenomenon according to the estimated remaining capacity of the unit cell. Any one of the first mode, the second mode for monitoring the output voltage of the unit cell, determining the discharge state when the monitored output voltage reaches the end voltage, and the third mode for switching the closed circuit to the open circuit. Adapted to perform the de is, it provides an over-discharge interrupting device adapted to store the operation information of the corresponding mode.

The over-discharge blocking control device according to an embodiment of the present application, unlike the conventional mechanical method that waits unconditionally for a predetermined time in consideration of the initial voltage delay phenomenon peculiar to the primary lithium unit battery, the pre-sequence of the unit battery (post-production storage The remaining capacity is continuously predicted, and the estimated residual capacity is compared with the reference capacity to determine whether the initial voltage delay of the unit battery is eliminated, and when the initial voltage delay is eliminated, the output voltage of the unit battery By switching on or off according to the monitored output voltage, overdischarge caused by excessive use of the unit cell and the resulting burst / explosion accident can be prevented.

1 and 2 is a view showing a conventional over-discharge blocking device.
3 is a view showing discharge characteristics of a general primary lithium unit battery.
4 is a block diagram showing an exemplary over-discharge blocking control device according to the present application.
5 is an exemplary circuit diagram of an over-discharge blocking device according to an embodiment of the present invention.
6 is a diagram illustrating a process of a control device operating according to an exemplary mode.

The present application relates to an over-discharge blocking device. An exemplary device of the present application may be a device applied to a primary lithium unit cell (Li / SOCl ₂ ).

Hereinafter, exemplary embodiments of the present application will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present application pertains can easily practice the present invention. However, the present application may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, parts irrelevant to the description are omitted for simplicity of explanation, and like reference numerals designate like parts throughout the specification.

4 is a block diagram showing an exemplary over-discharge blocking control device according to the present application. 5 is an exemplary circuit diagram of an over-discharge blocking device according to an embodiment of the present invention.

Referring to FIG. 4, the overdischarge device according to the exemplary embodiment of the present application includes a circuit unit 100, a voltage difference measuring unit 200, a switch unit 300, and a controller 400.

The circuit unit 100 electrically connects the unit cell and the load to supply power to the load. The circuit unit 100 may electrically connect the unit cell and the load to configure a closed circuit volatge (CCV).

The voltage difference measuring unit 200 includes a resistor connected in series with a load and measures a voltage difference across both ends of the resistance. The voltage difference may measure a current consumption flowing through both ends of the resistance, and calculate a voltage difference across the resistance by calculating the current consumption and the resistance. Referring to FIG. 5, the resistor may be a shunt resistor 200a and R7.

In one example, the voltage difference measuring unit 200 may generate an input signal containing information on the voltage difference and transmit it to the control unit 400.

In one embodiment, the voltage difference measuring unit 200 may measure the voltage difference across the resistor while the circuit unit 100 maintains the closed circuit. The voltage difference measurer 200 measures a voltage difference across the resistance depending on whether a closed circuit is formed, unlike a conventional mechanical judgment method of waiting a predetermined time unconditionally in consideration of an initial voltage delay phenomenon of a unit cell. It is possible to continuously predict the remaining capacity during the first stage of the unit cell, and to solve the problems caused by the conventional mechanical judgment, for example, the problem that the device does not operate at the proper reaction rate during the unit cell explosion.

In the present application, the term " continuously predicted " means predicted in real time, but the present invention is not limited thereto, and it is also included in continuously predicted prediction repeatedly at predetermined time intervals. For example, the predetermined time interval may be 0.5 seconds, 0.6 seconds, 0.7 seconds, 0.8 seconds, 0.9 seconds or 1.0 seconds intervals, but is not limited thereto.

In one embodiment, the voltage difference measurer 200 may repeatedly measure the current consumption flowing through both ends of the shunt resistors 200a and R7 at predetermined time intervals. The voltage difference measuring unit 200 counts the voltage difference as the first voltage difference, the second voltage difference, and the third voltage difference through an analog comparator according to the current consumption, and counts the plurality of voltage difference values. The remaining capacity of the unit cell can be estimated from the time period. Specifically, a voltage can be calculated from the consumed current, and the remaining capacity of the unit cell can be estimated from the calculated voltage and time.

The switch unit 300 operates in an on / off state, switches the circuit unit 100 to a closed circuit during on, and switches the closed circuit to an open circuit during off. It is prepared to. For example, when on, the unit cell may supply power to the load, and when the switch unit 300 is off, the unit cell and the load may be electrically disconnected. Referring to FIG. 5, the switch unit 300 may include a switching element such as a field effect transistor (FET) 300a and Q1.

The controller 400 estimates the remaining capacity of the unit battery based on the voltage difference measured by the voltage difference measuring unit 200, and compares the predicted remaining capacity of the unit battery with the reference capacity to resolve the initial voltage delay phenomenon. And whether the output voltage of the unit cell is monitored. The term "reference capacity" is an indicator for determining whether the initial voltage delay phenomenon of a unit cell is eliminated, and the reference capacity may be 20% of the nominal capacity of the unit cell, for example, a nominal voltage of 3.6V. The reference capacity of the primary lithium unit cell may be 3 Ah.

According to an embodiment, when the predicted remaining capacity of the unit battery is greater than or equal to the reference capacity, the controller 400 may determine that the initial voltage delay of the unit battery is eliminated and monitor the output voltage of the unit battery. The term "resolve the initial voltage delay state" means when the unit cell is introduced into the normal discharge section (section b in FIG. 3) after the initial voltage delay section (section a in FIG. 3).

In one example, the controller 400 may turn on or off the switch unit based on the monitored output voltage of the unit cell.

Specifically, the control unit 400 may turn off the switch unit 300 when the monitored output voltage reaches the termination voltage. The term "end voltage" refers to an allowable voltage or a cutoff voltage of a unit cell, and the end voltage corresponds to an intrinsic value of the unit cell. For example, the end voltage of the primary lithium unit cell may be 2.0V. have. When the output voltage reaches the end voltage, the unit cell may reach a so-called overdischarge state, which is rapidly discharged. The controller 400 may protect the circuit and the load from the unit battery in the overdischarge state by turning off the switch unit 300 when the unit battery is in the overdischarge state.

In one embodiment, the controller 400 may include a residual capacity predicting unit 410, a termination voltage monitoring unit 420, a time counting unit 430, and a memory unit 440. The controller 400 may include an active device 400a. Referring to FIG. 5, the active device 400a may be configured of an 8-bit microcomputer (MCU) (U1, ATtiny13A).

In one example, the remaining capacity estimator 410 may calculate the voltage difference measured by the voltage difference measurer 200 through an ADC comparator to predict the remaining capacity of the unit cell. For example, an ADC comparator can predict the remaining capacity of a unit cell through current integration.

The end voltage monitoring unit 420 may monitor whether the output voltage of the unit battery has reached the end voltage, and when the output voltage of the unit battery reaches the end voltage (or cutoff voltage), The switch unit 300 may be turned off. As described above, when the output voltage of the unit battery passes the end voltage, the unit battery reaches an over-discharge state that is rapidly discharged, which is likely to rupture / explode, and when the unit cell that reaches such an over-discharge state is forcibly used. Secondary safety accidents can occur. The controller 400 may monitor the output voltage of the unit cell and may turn off the switch unit 300 when the monitored output voltage reaches the termination voltage, thereby protecting the circuit and the load safely.

The time counting unit 430 may count an operating time of a unit cell. For example, the operating time of the primary lithium unit battery may be 20 hours or more, and the time counting unit 430 may contribute to predicting the remaining capacity of the unit battery by counting the operating time.

In addition, the memory unit 440 may store operation information including at least one of a remaining capacity, a discharge consumption capacity, a termination voltage, and an operation time of the unit battery. The memory unit 440 may store operation information at predetermined time intervals, and the time interval may vary depending on the type of operation information. For example, the operation information of the operation time may be measured in units of 10 minutes. The operation information on the termination voltage may be measured and stored in units of 0.5 seconds, but is not limited thereto. The memory unit 440 may include an electrically erasable programmable read-only memory (EEPROM). As described above, by storing the operation information of the unit battery, it is possible to follow-up management and analysis can be an efficient verification in the event of a safety accident.

In one example, the voltage supply unit 500 may be further provided to supply a driving voltage for driving the controller 400. Referring to FIG. 5, the voltage supply unit 500 may include capacitors 500a, C1, and C2.

In one embodiment, the over-discharge blocking device according to the present application may include a fuse 600 for blocking the over-current when the over-current of the unit cell occurs. As used herein, the term "overcurrent" means a current that is rapidly increased above a normal current. For example, a current of 5.5 A or more may be an overcurrent, and the circuit may be damaged if such overcurrent flows into the circuit.

The fuse 600 may be an overcurrent blocking device that physically blocks a unit cell and a circuit when an overcurrent occurs. Specifically, the fuse 600 may physically block the unit cell and the circuit when an overcurrent of 5.5 A or more occurs. In general, the fuse 600 has a unique rated current capacity, and the rated current capacity is determined according to the metal component constituting the fuse 600. The fuse 600 is located at the front of the unit cell and is melted when an overcurrent exceeding the rated current capacity is generated. As a result, the connection part of the unit cell and the circuit unit 100 melts, thereby physically preventing the inflow of the overcurrent. You can block.

In one example, the controller 400 may turn off the switch unit 300 for a predetermined time when an overcurrent of the unit cell occurs. The predetermined time may be, for example, 5 seconds or less, 10 seconds or less, 20 seconds or less, or 30 seconds or less, but is not limited thereto.

In one embodiment, the controller 400 may repeatedly turn on / off the predetermined time switch unit 300 when an overcurrent occurs. In general, since the overcurrent is a phenomenon in which the current temporarily increases rapidly (5.5 A or more), the control unit 400 repeatedly turns on / off the switch unit 300 at predetermined time intervals. The occurrence / release of an overcurrent condition can be continuously monitored. When the overcurrent state is released, the controller 400 may keep the switch unit 300 on.

In one embodiment, the controller 400 may determine an overcurrent when the current consumption of the unit cell measured by the voltage difference measurer 200 is greater than or equal to the reference current. The term "reference current" is an index for determining an overcurrent, and may be, for example, 5.5 A, but is not limited thereto.

 In one example, the over-discharge blocking device may operate by receiving power from a unit cell, for example, 10% or less, 8% or less, 6% or less or 5% or less of the total capacity of the unit cell. Can be implemented to consume.

In one embodiment, the unit cell may be a primary lithium unit cell. As the overdischarge blocking device of the present application is applied to the primary lithium unit battery, the overdischarge of the primary lithium unit battery and the resulting rupture / blasting accident can be prevented in advance.

The present application is composed of a circuit unit 100, a voltage difference measuring unit 200, a switch unit 300 and the control unit 400, the control unit is provided to perform any one of the 0 to the third mode It is all about blocking device. Descriptions overlapping with those related to the circuit unit 100, the voltage difference measuring unit 200, the switch unit 300, and the control unit (or the active element) 400 will be omitted below.

6 is a diagram illustrating a process of a control device operating according to an exemplary mode.

The exemplary control unit 400 is configured to perform any one of the 0 to 3 modes after presetting the reference capacitance in consideration of the nominal voltage, the discharge capacity, the end voltage, and the like of the unit cell. Operational information is saved. The operation information may be operation information such as the remaining capacity of the unit battery, the discharge consumption capacity, the cutoff voltage, the operation time, and the shutdown mode measured in each mode, and the operation information may be stored in the memory unit 440 described above. have.

Referring to FIG. 6, the zeroth mode is a storage mode for initializing an over-discharge blocking device by storing an initial voltage value of a unit battery as a correction value. The controller 400 may perform the zeroth mode when the circuit unit is first connected to the unit cell. For example, the control unit 400 operates a timer for counting the operating time of the unit cell from the time when the circuit unit is electrically connected to the (+) and (-) terminals of the unit cell, and in the 0 mode, the timer operates. It may be an initialization mode for setting an initial time point.

In one embodiment, the controller 400 performing the zero mode may correct the difference between the voltage across the resistor and the initial value of the active element MCU to be '0' under the condition that there is no load. The condition without the load means that the output of the ADC comparator is '0'. The initial voltage value and the correction value of the ADC comparator may be classified into operation information and stored in the memory unit 440.

In one example, when the unit battery and the circuit are connected, the controller 400 performing the zeroth mode may measure an initial voltage value of the unit battery after having a predetermined standby time. For example, the standby time may be It may be 10 minutes. The controller 400 may perform the first mode when the correction value storage of the ADC comparator is completed.

The first mode is a mode for estimating the remaining capacity of the unit cell by using current integration, and comparing the predicted remaining capacity of the unit cell with the reference capacity to determine whether to resolve the initial voltage delay state. The controller 400 performing the first mode predicts the remaining capacity of the unit cell based on the voltage difference measured by the voltage difference measuring unit 200, and when the predicted remaining capacity of the unit cell is less than the reference capacity, the unit cell It can be determined by canceling the initial voltage delay state of.

In one embodiment, when the remaining capacity of the unit cell predicted in the first mode is less than the reference capacity, for example, 20% or less, 15% or less or 10% or less of the nominal capacity of the unit cell. In this case, the second mode may be performed.

In detail, the controller 400 may switch from the first mode to the second mode when 20% of the nominal capacity of the unit battery is consumed (3 Ah in the case of the primary lithium battery). For example, in the case of the primary lithium unit battery, the controller 400 maintains the first mode until the remaining capacity of the primary lithium unit battery is consumed up to 3 Ah, and performs the second mode when the primary lithium unit battery is consumed above 3 Ah. Can be.

In one example, the controller 400 performing the first mode may estimate the remaining capacity of the unit cell by integrating the consumption currents measured by a predetermined number of times in the voltage difference measuring unit 200 at a predetermined time interval. The time interval may be arbitrarily set, for example, 0.5 second intervals, but is not limited thereto. Integration value, operating time in the first mode. The voltage difference and the corresponding mode may be classified into operation information and stored in the memory unit 440.

The controller 400 may not block the output voltage of the unit cell even when an unexpected low voltage occurs at the time of switching from the first mode to the second mode. Since the low voltage may occur even in the end section (section c of FIG. 2) where the output voltage of the unit cell reaches the end voltage, the controller 400 may not generate the second voltage only during the normal discharge section (section b of FIG. 2) of the unit cell. Mode can be performed.

The second mode may be a determination mode that monitors the output voltage of the unit cell and determines the discharge state when the monitored output voltage reaches the termination voltage. The unit battery determined to be in the discharge state in the second mode may no longer be used, and accordingly, the controller 400 may perform the third mode when it is determined to be in the discharge state.

In one example, when the current consumption of the unit cell measured in any one of the first or second mode is measured above the reference current, the control unit 400 determines that the over-current state, and the switch unit 300 is predetermined You can turn off the time. Since the overcurrent is a temporary phenomenon in which the current suddenly increases rapidly, the controller 400 repeatedly turns on / off the switch unit 300 at predetermined time intervals, thereby generating an overcurrent condition. Release can be monitored continuously. For example, when the current consumption of the unit cell is less than or equal to the reference current, for example, less than or equal to 5.5 A, the controller 400 determines that the overcurrent state is released, and maintains the switch unit 300 on. Can be.

In one example, the controller 400 may be provided to store the overcurrent state as operation information. For example, the operation information may be stored in the memory unit 440.

In an embodiment, the controller 400 may store operation information including a discharge capacity, an operation time, a corresponding voltage, and a corresponding mode of the unit battery at predetermined time intervals in the second mode, and the operation information may be stored in the memory unit 440. ) Can be stored. The control unit 400 may store the operation information in the memory unit 440 in the second mode, so that post-management and analysis may be performed, thereby enabling efficient verification when a safety accident occurs.

In one example, the controller 400 may be provided to continuously monitor the output voltage of the unit battery a predetermined number of times along a predetermined time interval, when the output voltage of the unit battery in the second mode is monitored below the end voltage. . The time interval and the number of times may be, for example, 0.5 seconds, but is not limited thereto.

The controller 400 may continuously perform the third mode when the output voltage of the unit cell is less than or equal to the final voltage after continuously monitoring the output voltage of the potential battery. If the output voltage of the unit battery is equal to or less than the final voltage after continuously monitoring, the controller 400 may determine the discharge state and perform the third mode.

The third mode may be a blocking mode for switching the closed circuit to the open circuit. The control unit 400 performing the third mode may permanently turn off the switch unit 300 to prevent reuse of the unit cell in a discharged state.

The blocking mode may be classified into operation information and stored in the memory unit 440. Accordingly, even if the controller 400 performing the third mode is unexpectedly reset, the switch 400 may be maintained off based on the information stored in the memory 440. As described above, by storing the blocking mode as operation information, it is possible to permanently prohibit reuse of the unit cell in the discharged state, and to prevent secondary safety accidents caused by the unit cell in the discharged state.

In one embodiment, the controller 400 may not perform the 0 to 3 modes when an overcurrent occurs. For example, the controller 400 continuously monitors the consumption current flowing in the circuit when the overcurrent occurs, and then may perform any one of the 0 to 3 modes when the consumption current is less than or equal to the reference current. For example, the reference current may be 5.5 A. As described above, the controller 400 continuously monitors the current consumption without performing the mode when the overcurrent occurs, thereby preventing damage to the circuit due to the overcurrent.

In one example, the unit cell may be a primary lithium battery.

As described above, although the present application has been described by way of limited embodiments and drawings, the present application is not limited thereto, and various modifications and variations may be possible.

100: circuit part
200: voltage difference measuring unit
200a: shunt resistance
300: switch unit
300a: field effect transistor
400: control unit
400a: active device
500: voltage supply
500a: capacitor
600: fuse

Claims (21)

A circuit unit electrically connecting the unit cell and the load to supply power to the load;
A voltage difference measurer including a resistor connected in series with the load and measuring a voltage difference across both ends of the resistor;
A switch unit arranged to operate on / off and to switch the circuit unit to the closed circuit when it is on, and to switch the closed circuit to the open circuit when it is off; And
Predict the remaining capacity of the unit cell based on the voltage difference measured by the voltage difference measurement unit, and compares the estimated remaining capacity of the unit cell with the reference capacity to determine whether the initial voltage delay phenomenon is resolved and whether the output voltage of the unit battery is monitored. Over-discharge blocking device comprising a control unit for determining. The over-discharge blocking device of claim 1, wherein the controller determines that the initial voltage delay of the unit battery is canceled when the predicted remaining capacity of the unit battery is equal to or greater than the reference capacity, and the output voltage of the unit battery is monitored. The method of claim 2,
The control unit is an over-discharge cut-off device for turning on or off the switch unit based on the output voltage of the monitored unit cell. The over-discharge blocking device of claim 1, wherein the controller includes a residual capacity estimator configured to calculate a residual capacity of the unit cell by calculating a voltage difference measured by the voltage difference measurer through an ADC comparator. The method of claim 3, wherein
The control unit includes a termination voltage monitoring unit for monitoring whether the output voltage of the unit cell has reached the termination voltage. The method of claim 5,
The control unit is configured to turn off the switch unit when the output voltage of the unit cell reaches the end voltage. The method of claim 1,
The control unit includes a time discharge unit for counting the operating time of the unit battery. The method of claim 1,
The control unit includes an over-discharge blocking device including a memory unit for storing the operation information including one or more of the remaining capacity, the discharge consumption capacity, the end voltage and the operating time of the unit cell. The method of claim 1,
An over-discharge breaking device including a fuse for cutting off the over-current when an over-current of the unit cell occurs. The method of claim 1,
The control unit is configured to turn off the switch unit for a predetermined time when an overcurrent occurs in the unit cell. The method of claim 1,
The unit cell is an over-discharge blocking device comprising a primary lithium unit cell. A circuit unit electrically connecting the unit cell and the load to supply power to the load;
A voltage difference measurer including a resistor connected in series with the load and measuring a voltage difference across both ends of the resistor;
A switch unit arranged to operate on / off, to switch the circuit unit to the closed circuit when it is on, and to switch the closed circuit to the open circuit when it is off; And
Mode 0, which initializes the over-discharge blocking device by storing the initial voltage value of the unit battery as a correction value, predicts the remaining capacity of the unit battery using current integration, and compares the estimated remaining capacity of the unit electron with the reference capacity. A first mode for determining whether to eliminate the voltage delay phenomenon, a second mode for monitoring the output voltage of the unit cell, determining the discharge state when the monitored output voltage reaches the end voltage, and a third mode for switching the closed circuit to the open circuit The over-discharge blocking device is provided to perform any one of the modes, and to store the operation information of the mode. The method of claim 12,
The control unit performs the zero discharge mode when the circuit unit is first connected to the unit cell. The method of claim 12,
The controller performs the second mode when the remaining capacity of the unit cell predicted in the first mode is 20% or less than the nominal capacity of the unit cell. The method of claim 12,
The controller for performing the second mode only in the normal discharge section of the unit cell. The method of claim 12, wherein the control device determines that the current consumption of the unit cell measured in any one of the first mode or the second mode is greater than the reference current, and determines that the over-current state, the switch unit for a predetermined time off Over-discharge disconnecting device. The method of claim 16,
The controller is configured to store the overcurrent state as operation information. The method of claim 12,
The controller is configured to store the discharge capacity of the unit battery, the operating time, the voltage, and the operation information including the corresponding mode at predetermined time intervals in the second mode. The method of claim 12,
And the control unit is configured to continuously monitor the output voltage of the unit battery a predetermined number of times along a predetermined time interval when the output voltage of the unit battery is monitored to be less than or equal to the end voltage in the second mode. The method of claim 19,
The control unit performs the third mode when the output voltage is less than the final voltage after continuously monitoring the output voltage of the unit cell. The method of claim 12,
The unit cell is an over-discharge blocking device comprising a primary lithium unit cell.

Images