KR20110037740A - Battery measurement method of lithium primary cell and apparatus thereof - Google Patents

Abstract

PURPOSE: A battery measuring method of a lithium primary battery and a device thereof are provided to effectively generate an alarm signal according to the power amount of the lithium primary battery. CONSTITUTION: An input unit(310) receives a measured voltage value and information about the amount of using currents of a lithium primary battery which supplies power to a device. If the measured voltage value of the lithium primary battery is smaller than a reference voltage value, a calculating unit(330) increases a counter, and calculates the ratio of the amount of using currents to the current capacity of the lithium primary battery. A controller(340) generates an alarm signal corresponding to the ratio of the amount of using currents to the current capacity of the lithium primary battery. An alarm generating unit(350) transmits a generated alarm signal to the outside.

Description

BATTERY MEASUREMENT METHOD OF LITHIUM PRIMARY CELL AND APPARATUS THEREOF

The present invention relates to a method for measuring a battery of a lithium primary battery and a device thereof. More particularly, by using a combination of voltage and current usage of a lithium primary battery, an alarm signal according to the amount of battery of the lithium primary battery can be effectively The present invention relates to a battery measuring method of a lithium primary battery that can be produced, and a device thereof.

Recently, with the development of IT technology, the usage of lithium batteries as an energy source is gradually increasing. Lithium battery (lithium battery) is a battery using a metal lithium as a negative electrode, mainly primary batteries, and compared to the manganese battery is higher in voltage and energy density, and is used as a power source such as a camera or an electronic clock. In particular, the lithium-Socl2 battery is a non-rechargeable primary battery having an electromotive force corresponding to about 3.0 to 3.7V higher than a general voltage and having a high energy density. Therefore, lithium-Socl2 batteries are mainly used for memory backup, remote meter reading, and RFID.

1 is a graph showing the voltage characteristics of a lithium primary cell battery. In Figure 1, the horizontal axis represents time and the vertical axis represents the measured voltage of the lithium primary battery. As shown in FIG. 1, even though the battery is exhausted to about 90% due to the characteristics of the lithium primary battery, the voltage of the lithium primary battery is almost constant, and the measured voltage of the lithium primary battery must be at least 90% exhausted. It can be seen that is rapidly reduced. As shown in the voltage curve graph of a lithium primary battery, a very rapid voltage change occurs when the battery is almost exhausted.

Therefore, since the amount of remaining battery of the lithium primary battery cannot be measured through the measurement voltage of the lithium primary battery according to the prior art, it is impossible to predict the actual usable battery capacity of the lithium primary battery, and to replace the lithium primary battery. It is difficult to judge the timing accurately. In particular, the lithium primary battery cannot be charged, and even if the lithium primary battery is discharged, it is difficult to predict the discharge in advance, so an accident may occur such that the operation of the IT system is stopped due to the discharge of the lithium primary battery. .

Accordingly, the technical problem to be achieved by the present invention is to provide a method and apparatus for measuring a battery of a lithium primary battery, which can predict the battery remaining amount of the lithium primary battery in advance and cope with it quickly.

The battery measuring method of a lithium primary battery according to an embodiment of the present invention for achieving the technical problem, by receiving the measured voltage value and the current usage for a certain period of time, the lithium primary battery for supplying power to the device, Comparing the measured voltage with a reference voltage, if the measured voltage of the lithium primary battery is less than the reference voltage, increasing a counter, calculating a ratio of the current usage to the current capacity of the lithium primary battery, Generating an alarm signal corresponding to the ratio of the current usage, and transmitting the generated alarm signal to the outside.

The generating of an alarm signal corresponding to the ratio of the current usage may include comparing the number of the counters with a reference value if the ratio of the current usage is less than a first threshold value, and if the number of the counters is greater than the reference value. Determining whether a voltage drop of the lithium primary battery has occurred and generating the alarm signal when a voltage drop occurs, and if the ratio of the current usage is greater than the first threshold and less than a second threshold, the lithium 1 Determining whether a voltage drop of the secondary battery has occurred and generating the alarm signal when the voltage drop occurs, and generating the alarm signal when the ratio of the current usage is greater than the second threshold value. .

When the measured voltage of the lithium primary battery is smaller than the previous measured voltage, it can be determined that the voltage drop of the lithium primary battery has occurred.

The method may further include converting the measured voltage value and the current usage amount into a digital form.

The calculating of the ratio of the current usage to the current capacity of the lithium primary battery may be calculated according to the following equation.

Total Current = Sleep Current Usage + Tx Current Usage + Rx Current Usage

Percentage of current usage [%] = (total current used / current capacity) * 100

Here, the sleep current usage is the current usage of the lithium primary battery when the device is in the sleep mode, the Tx current usage is the current usage of the lithium primary battery when the device is in the data transmission state, the Rx current usage is The current consumption of the lithium primary battery when the device is in a data reception state.

An apparatus for measuring a battery of a lithium primary battery according to another exemplary embodiment of the present invention may include an input unit configured to receive a measured voltage value of a lithium primary battery supplying power to a device and a current usage amount for a predetermined period of time. If the measured voltage is less than the reference voltage, the counter is incremented, the calculating unit for calculating the ratio of the current usage to the current capacity of the lithium primary battery, the control unit for generating an alarm signal corresponding to the ratio of the current usage, and the It includes an alarm alarm unit for transmitting the generated alarm signal to the outside.

The apparatus may further include an A / D converter configured to convert the measured voltage value and the current usage amount into a digital form.

The lithium primary battery is a lithium-Socl2 battery, and the secondary battery is composed of an electric double layer capacitor (EDLC) or a hybrid layer capacitor (HLC), and the lithium primary battery may be connected in parallel with the secondary device. .

The device is a device for a remote meter reading, the sleep mode and the active mode can be switched periodically.

As described above, according to the present invention, by using the remaining battery amount of the lithium primary battery in combination of the magnitude of the voltage and the amount of current, the remaining battery amount of the lithium primary battery can be confirmed more accurately, and the exhausted state is notified by an alarm. In order to know the amount of exhausted battery beforehand. In addition, by calculating the ratio of the current usage to the current capacity, and divided into three types of algorithms according to the calculation result, it is possible to take more effective and appropriate precautions according to the remaining battery capacity of the lithium primary battery.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

2 is a view for explaining a battery measuring system of a lithium primary battery according to an embodiment of the present invention.

As shown in FIG. 2, a battery measuring system of a lithium primary battery includes a lithium primary battery 100, a secondary battery 200, and a battery measuring apparatus 300. The lithium primary battery 100 is a lithium primary battery that is the target of battery measurement according to an embodiment of the present invention, and preferably represents a lithium-Socl2 battery used for remote meter reading.

The lithium primary battery 100 supplies power to the device 50, which is a main body of various operations, and may be included and installed in the device. In particular, the device 50 according to the embodiment of the present invention may have a remote meter reading function, and the active mode and the sleep mode are alternately converted in time series. In the active mode, the device 50 transmits the read data to a higher layer device through Zigbee communication.

The secondary battery 200 and the battery measuring device 300 are connected in parallel with the lithium primary battery 100. The secondary battery 200 has an auxiliary function of reducing a change in the amount of current with respect to the lithium primary battery 100, and is an electric double layer capacitor (EDLC) or a hybrid layer capacitor (HLC). Layer Capacitor). The electric double layer capacitor uses an electric double layer phenomenon in which electricity is stored on the contact surface when a direct current voltage is applied to the solid electrode and the electrolyte solution, and the hybrid layer capacitor uses a hybrid layer in which electricity is stored around the solid electrode.

FIG. 3 is a diagram illustrating an amount of current measured when a secondary battery is connected to a lithium primary battery, and FIG. 4 is a graph showing a current capacity according to each amount of current.

In general, the capacity of the battery is different according to the operation profile of the lithium primary battery 100, and current prediction is very difficult in the pulsed current use scheme in which the sleep mode and the active mode are switched. In order to keep the pulsed current usage constant, the capacity of the battery can be increased as much as possible by connecting the secondary battery 200 in parallel with the battery measuring apparatus 300, and the prediction of the usable current capacity becomes easy.

In FIG. 3, the actual amount of current used is indicated by a solid line, and the amount of measured current when the secondary battery is connected is indicated by a dotted line. As shown in FIG. 3, the pulsed current having a large change in the amount of current according to the sleep mode and the active mode is difficult to measure the average current consumption. However, when the secondary batteries 200 are connected in parallel, the size change of the measured current amount becomes very small as shown by the dotted line of FIG. 3, so that the current capacity according to the average current amount can be easily predicted as shown in FIG. 4.

Figure 4 shows the actual available current capacity of the lithium primary battery, the horizontal axis represents the time, the vertical axis represents the magnitude of the voltage. As shown in Figure 4 it can be seen that the size of the current capacity (Ah) available for one hour varies depending on the size of the current used, the available time is also different. Therefore, when the secondary battery is used, the average amount of current used can be measured, and thus the current capacity according to the amount of current used can be estimated.

As described above, since the secondary battery 200, which serves as an auxiliary function to the lithium primary battery 100, is connected in parallel to the lithium primary battery 100, the voltage suddenly drops even when the battery supplied to the device is almost exhausted. Dropping voltage drop phenomenon is difficult to occur.

The battery measuring apparatus 300 is connected in parallel with the secondary battery 200 with respect to the lithium primary battery 100, and through the battery measuring algorithm using the measured voltage value and the current amount of the lithium primary battery 100. The battery remaining amount of the primary battery 100 is measured and correspondingly an alarm alarm is generated.

5 is a view showing the configuration of a battery measuring device of a lithium primary battery according to an embodiment of the present invention. The battery measuring apparatus 300 includes an input unit 310, an A / D converter 320, a calculator 330, a controller 340, and an alarm alarm unit 350.

The input unit 310 receives an active mode conversion signal from a device powered by a lithium primary battery, and receives a measured voltage value and an amount of current of the lithium primary battery. The A / D converter 320 converts the measured voltage value and the current amount of the analog lithium primary battery into a digital form.

The calculating unit 330 increases the counter when the measured voltage of the lithium primary battery 100 is lower than the reference voltage, and calculates a ratio of the current consumption to the current capacity of the lithium primary battery 100. The controller 340 generates an alarm signal corresponding to the ratio of the current usage to the current capacity of the lithium primary battery 100, and the alarm alarm unit 350 transmits the generated alarm signal to the outside.

In particular, the control unit 340 calculates the ratio of the current usage to the current capacity of the lithium primary battery 100, divided by the case where the current usage ratio is 60% or less, 60% to 80%, 80% or more. Control alarm signal generation in response to each situation.

Hereinafter, a method of measuring the battery of the lithium primary battery 100 by the battery measuring apparatus 300 will be described with reference to FIG. 6. 6 is a flowchart illustrating a measuring method of a lithium primary battery battery according to an exemplary embodiment of the present invention.

First, a device that receives power from the lithium primary battery wakes up and receives a signal from the device that it has been converted from the sleep mode to the active mode (S610). Then, the current consumption and voltage value of the lithium primary battery is received from the device (S620), and the analog current consumption and voltage value are converted to digital (S630).

The battery measuring apparatus 300 compares the measured voltage of the lithium primary battery with a reference value (S640). The reference value may be 0.15V higher than the cut off voltage or 3.1V. That is, when the measured voltage of the lithium primary battery 100 is lower than the (Cut off Voltage + 0.15V) voltage or lower than the 3,1V voltage, the battery measuring device 300 is regarded as the first indication of discharge. do.

When the measured voltage of the lithium primary battery 100 is smaller than the reference value, the battery measuring apparatus 300 increases the counter (S645), and calculates a ratio of the current consumption to the current capacity of the lithium primary battery (S650). ).

The battery measuring apparatus 300 continuously records the operating days and the standby mode state of the device in order to calculate the amount of current used by the lithium primary battery. That is, the number of operating days from the first production date of the device is recorded, and the fluctuating data is always stored. It also records the time the device has been in sleep mode since the minimum production of the device.

The battery measuring apparatus 300 calculates the amount of current used for a certain period of time through the number of operating days, and calculates the ratio of the current consumption to the current capacity of the lithium primary battery as shown in Equation 1 below.

Sleep Current Consumption = Operating Days * Sleep Current * 24

Tx current usage = number of operating days * [Tx current * (actual Tx seconds / 3600)] * 24

Rx Current Consumption = Standby Mode * RX Current / 60 = Rx Current Consumption

Total Current = Sleep Current Usage + Tx Current Usage + Rx Current Usage

Percentage of current usage [%] = (total current used / current capacity) * 100

Here, the sleep current usage is the current usage of the lithium primary battery when the device is in sleep mode, the Tx current usage is the current usage of the lithium primary battery when the device is in the data transmission state, the Rx current usage is the device receives data In this state, the current consumption of the lithium primary battery is shown.

Each current usage amount is proportional to the product of the current amount and time, and the current usage ratio is calculated as the ratio of the current usage to the current capacity. That is, as described with reference to FIGS. 3 and 4, in a state in which the current capacity for the current amount has been previously obtained, the average current amount actually used for a predetermined period of time is measured to determine the ratio of the actual current amount to the available current capacity. You can get it.

If the ratio of the current consumption to the current capacity of the lithium primary battery is calculated to be 60% or less, the number of counters is compared (S660). If the number of counters is 3 or more, the voltage is determined through an offset table that records the magnitude of the previous voltage. It is determined whether the drop (S670).

Table 1 below shows an example of an offset table showing the result of measuring the magnitude of the voltage at regular intervals.

As shown in Table 1, the battery measuring apparatus 300 measures the amount of current and voltage value of the lithium primary battery 100 about once a day or two, and records the measured data in the offset table. Here, the battery measuring apparatus 300 may determine whether the voltage drops through the offset data, which is a voltage difference from the previous voltage.

If the measured voltage is smaller than the magnitude of the previously measured voltage, that is, when a voltage drop occurs, it is determined that the remaining battery level of the lithium primary battery 100 is almost exhausted and an alarm alarm is transmitted to the outside (S680). .

In step S650, if the ratio of the current usage to the current capacity of the lithium primary battery is 60% or more and 80% or less, it is determined that the situation is more urgent than the previous case, and the flow proceeds directly to S670 regardless of the count. Determine whether or not. Similarly, if the measured voltage is smaller than the magnitude of the previously measured voltage, it is determined that the remaining battery capacity of the lithium primary battery is exhausted and transmits an alarm alert to the outside (S680).

In step S650, if the ratio of the current usage to the current capacity of the lithium primary battery is 80% or more, it is determined that it is the most urgent situation and the remaining battery amount of the lithium primary battery 100 is exhausted regardless of whether the voltage drops. It is determined that it has been delivered to the alarm alarm to the outside (S680).

As described above, according to the exemplary embodiment of the present invention, the remaining battery amount of the lithium primary battery is combined with the magnitude of the voltage and the current usage, so that the remaining battery amount of the lithium primary battery can be measured more accurately, and the exhausted state is alarmed. Notify the user in advance that the battery level will be exhausted.

In addition, by calculating the ratio of the current consumption to the current capacity, and divided into three types of algorithms according to the calculation result, it is possible to take precautions on the battery remaining amount of the lithium primary battery more effectively and in detail.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a graph showing the voltage characteristics of a lithium primary cell battery.

2 is a view for explaining a battery measuring system of a lithium primary battery according to an embodiment of the present invention.

3 is a view for explaining an amount of current measured when a secondary battery is connected to a lithium primary battery.

4 is a graph showing the current capacity according to each current amount.

5 is a view showing the configuration of a battery measuring device of a lithium primary battery according to an embodiment of the present invention.

6 is a flowchart illustrating a measuring method of a lithium primary battery battery according to an exemplary embodiment of the present invention.

Claims (12)

Receiving the measured voltage value of the lithium primary battery powering the device and the current usage for a predetermined period, and comparing the measured voltage with a reference voltage, Increasing the counter when the measured voltage of the lithium primary battery is less than the reference voltage, and calculating a ratio of the current usage to the current capacity of the lithium primary battery; Generating an alarm signal corresponding to the ratio of the current usage, and The battery measuring method of the lithium primary battery comprising the step of transmitting the generated alarm signal to the outside. The method of claim 1, Generating an alarm signal corresponding to the ratio of the current usage, If the ratio of the current usage is less than the first threshold value, the number of the counter is compared with the reference value, and if the number of the counter is larger than the reference value, it is determined whether the voltage drop of the lithium primary battery has occurred and the voltage drop is Generating the alarm signal when it occurs; If the ratio of the current usage is greater than the first threshold and less than the second threshold, determining whether a voltage drop of the lithium primary battery has occurred and generating the alarm signal when the voltage drop has occurred; and And generating the alarm signal when the ratio of the current usage amount is greater than the second threshold value. The method of claim 2, And determining that a voltage drop of the lithium primary battery occurs when the measured voltage of the lithium primary battery is smaller than a previous measurement voltage. The method of claim 1, The method of measuring a battery of a lithium primary battery further comprising the step of converting the measured voltage value and the current usage in a digital form. The method of claim 1, Calculating a ratio of the current usage to the current capacity of the lithium primary battery, Battery measurement method of the lithium primary battery calculated according to the following equation: Total Current = Sleep Current Usage + Tx Current Usage + Rx Current Usage Percentage of current usage [%] = (total current used / current capacity) * 100 Here, the sleep current usage is the current usage of the lithium primary battery when the device is in the sleep mode, the Tx current usage is the current usage of the lithium primary battery when the device is in the data transmission state, the Rx current usage is The current consumption of the lithium primary battery when the device is in a data reception state. An input unit for receiving a measured voltage value of a lithium primary battery supplying power to a device and a current usage for a predetermined period of time; An operation unit for increasing a counter when the measured voltage of the lithium primary battery is smaller than a reference voltage and calculating a ratio of the current usage to the current capacity of the lithium primary battery; A controller configured to generate an alarm signal corresponding to the ratio of the current usage amount, and Battery measuring apparatus of a lithium primary battery comprising an alarm alarm unit for transmitting the generated alarm signal to the outside. The method of claim 6, The control unit, If the ratio of the current usage is less than the first threshold value, the number of the counter is compared with the reference value, and if the number of the counter is larger than the reference value, it is determined whether the voltage drop of the lithium primary battery has occurred, Generate the alarm signal in case of occurrence, When the ratio of the current usage is greater than the first threshold value and less than the second threshold value, it is determined whether the voltage drop of the lithium primary battery has occurred, and generates the alarm signal when the voltage drop occurs. The battery measuring device of the lithium primary battery to generate the alarm signal when the ratio of the current usage is greater than the second threshold. The method of claim 7, wherein The control unit, The battery measuring device of the lithium primary battery to determine that the voltage drop of the lithium primary battery occurs when the measured voltage of the lithium primary battery is less than the previous measurement voltage. The method of claim 6, The battery measuring device of the lithium primary battery further comprises an A / D conversion unit for converting the measured voltage value and the current usage in a digital form. The method of claim 6, The calculation unit, Battery measuring apparatus of the lithium primary battery for calculating the ratio of the current consumption to the current capacity of the lithium primary battery according to the following equation: Total Current = Sleep Current Usage + Tx Current Usage + Rx Current Usage Percentage of current usage [%] = (total current used / current capacity) * 100 Here, the sleep current usage is the current usage of the lithium primary battery when the device is in the sleep mode, the Tx current usage is the current usage of the lithium primary battery when the device is in the data transmission state, the Rx current usage is The current consumption of the lithium primary battery when the device is in a data reception state. The method of claim 6, The lithium primary battery is a lithium-Socl2 battery, and the secondary battery is composed of an electric double layer capacitor (EDLC) or a hybrid layer capacitor (HLC), and lithium connected in parallel with the secondary device with respect to the lithium primary battery. Battery measuring device of primary cell. The method of claim 11, The device is a device for a remote meter reading, the battery measuring device of the lithium primary battery is periodically switched between the sleep mode and the active mode.

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