JP2002214310A - Secondary battery unit and residual capacity display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive structure and to precisely detect the residual capacity of a battery cell. SOLUTION: A memory element 13 is constituted so as to have a current value data storage part 31 for defining a plurality of current value data corresponding to various current values carried to the battery cell; a voltage data storage part 32 for defining a plurality of voltage data corresponding various voltages of the battery cell; and a residual capacity data storage part 33 for defining corresponding residual capacity data for each combination of the current value data with the voltage data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a secondary battery unit including a rechargeable battery cell such as a lithium polymer battery, and a remaining capacity display device suitable for displaying the remaining battery capacity of the secondary battery unit.

[0002]

2. Description of the Related Art For example, mobile phones, small video cameras,
For devices that use secondary batteries, such as digital cameras, portable audio devices, and portable personal computers,
For the purpose of displaying the state of charge or the time of replacement, it is required to measure the electric capacity of the secondary battery, that is, the remaining capacity. One method for measuring the remaining capacity of the secondary battery is to uniquely define the correlation between the battery voltage and the remaining capacity and to estimate the remaining capacity by detecting the voltage of the battery cell, There is known a method of calculating a remaining capacity by integrating a charge / discharge current.

[0003]

However, since the remaining capacity and the battery voltage do not always correspond one-to-one,
The above-described method of calculating the remaining capacity by detecting the voltage of the battery cell has a problem that it is difficult to accurately measure the remaining capacity of the battery cell. On the other hand, the method of calculating the remaining capacity by integrating the charge / discharge current of the secondary battery allows the remaining capacity of the battery cell to be calculated with high accuracy, but requires a large number of components and circuits as a current integration circuit. There is a problem that the cost required for measuring the capacity increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is a secondary battery unit and a remaining capacity display device which can be configured at low cost and can detect the remaining capacity of a battery cell with high accuracy. The purpose is to provide.

[0005]

Accordingly, a secondary battery unit according to the present invention is a secondary battery unit comprising a rechargeable battery cell and a memory element, wherein the memory element is a battery. A current value data storage unit that defines a plurality of current value data corresponding to various current values flowing through the cell,
A voltage data storage unit that defines a plurality of voltage data corresponding to various voltages of the battery cell; and a remaining capacity data corresponding to each combination of the plurality of current value data and the plurality of voltage data. And a remaining capacity data storage unit.

The memory element may have a temperature correction data storage unit for storing a plurality of temperature correction data corresponding to various temperatures at a predetermined position of the secondary battery unit (claim 2). Further, the memory element includes a temperature data storage unit that defines a plurality of temperature data corresponding to various temperatures at a predetermined position of the secondary battery unit, and the temperature correction data storage unit stores a plurality of temperature data for each of the plurality of temperature data. May be stored (claim 3).

Further, the memory element may have a deterioration correction data storage unit for storing a plurality of deterioration correction data corresponding to various deterioration states of the battery cell.
Further, the memory element includes a deterioration state data storage unit that defines a plurality of deterioration state data corresponding to various deterioration states of the battery cell, and the deterioration correction data storage unit is provided for each of the plurality of deterioration state data. The corresponding deterioration correction data may be stored (claim 5).

Further, the deterioration state of the battery cell may be represented by a voltage drop value in a discharge test of the battery cell. Further, the battery cell may be a lithium secondary battery. Further, the remaining capacity display device of the present invention is a remaining capacity display device for displaying the remaining capacity of the battery cell in the secondary battery unit on a display unit, wherein the current value measuring unit measures a current value flowing through the battery cell. And a voltage measuring unit that measures the voltage of the battery cell, a voltage measured by the voltage measuring unit, and a current value measured by the current value measuring unit. A remaining capacity data obtaining unit for obtaining the remaining capacity data to be processed, a calculating unit for calculating the remaining capacity of the battery cell based on the remaining capacity data obtained by the remaining capacity data obtaining unit, and a calculating unit for calculating the remaining capacity. A display control unit for displaying the remaining capacity of the battery cell on the display unit.

Further, the remaining capacity display device of the present invention is a remaining capacity display device for displaying the remaining capacity of the battery cell in the secondary battery unit on a display unit, wherein the current value for measuring a current value flowing through the battery cell is provided. A value measuring unit, a voltage measuring unit that measures the voltage of the battery cell, and the remaining capacity data storage based on the voltage measured by the voltage measuring unit and the current value measured by the current value measuring unit. A remaining capacity data obtaining unit for obtaining the corresponding remaining capacity data from the unit, a calculating unit for calculating the remaining capacity of the battery cell based on the remaining capacity data obtained by the remaining capacity data obtaining unit, and the calculating unit A display control unit for displaying the remaining capacity of the battery cell calculated by the display unit on the display unit, and the calculation unit uses the temperature correction data stored in the temperature correction data storage unit to display the remaining capacity of the battery cell. Calculate remaining capacity (Claim 9).

The memory element of the secondary battery unit includes a deterioration correction data storage unit for storing a plurality of deterioration correction data corresponding to various deterioration states of the battery cell.
The calculation unit may calculate the remaining capacity of the battery cell also using the deterioration correction data stored in the deterioration correction data storage unit. Further, the memory element of the secondary battery unit includes a deterioration state data storage unit that defines a plurality of deterioration state data corresponding to various deterioration states of the battery cell, and the deterioration correction data storage unit includes the plurality of deterioration correction data storage units. The deterioration correction data corresponding to each of the deterioration state data may be stored.

Further, the remaining capacity display device of the present invention is a remaining capacity display device for displaying the remaining capacity of the battery cell in the secondary battery unit on a display unit, wherein the current value for measuring the current value flowing through the battery cell is provided. A value measurement unit, a voltage measurement unit that measures the voltage of the battery cell, and the remaining capacity data storage based on the voltage measured by the voltage measurement unit and the current value measured by the current value measurement unit. A remaining capacity data obtaining unit for obtaining the corresponding remaining capacity data from the unit, a calculating unit for calculating the remaining capacity of the battery cell based on the remaining capacity data obtained by the remaining capacity data obtaining unit, and the calculating unit A display control unit for displaying the remaining capacity of the battery cell calculated by the display unit on the display unit, wherein the calculation unit uses the deterioration correction data stored in the deterioration correction data storage unit to store the remaining capacity of the battery cell. Calculate remaining capacity It is characterized in Rukoto (claim 1
0).

[0012] The deterioration state of the battery cell may be represented by a voltage drop value in a discharge test of the battery cell (claim 13), and the battery cell is a lithium secondary battery. (Claim 14).

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing a configuration of a secondary battery unit as one embodiment of the present invention. A secondary battery unit (hereinafter, sometimes referred to as a battery unit) 1 as one embodiment of the present invention is substantially similar in appearance to a secondary battery such as a so-called battery pack, and includes a mobile phone, a small video camera, It is used as a drive power source for power-consuming external devices (hereinafter, referred to as “power-consuming devices”) such as digital cameras, portable audio devices, and portable personal computers. As shown in FIG. 1, the battery unit 1 includes a rechargeable battery cell 11 and a circuit unit 12.

The battery cell 11 is constituted by a secondary battery such as a lithium polymer battery or a lithium ion battery. Examples of the lithium polymer battery and the lithium ion battery include those using a lithium transition metal composite oxide such as a lithium cobalt composite oxide as a positive electrode and using a carbon material such as graphite as a negative electrode. In addition,
This battery cell 11 does not have any arithmetic function.

The circuit section 12 includes an EEPROM (memory element) 13, a protection circuit 14, a fuse (FUSE) 15,
Thermistor (temperature measurement unit) 16, low-pass filter (L
PF) 17 and 18 and a resistor 19. The memory elements 13 constituting these circuit sections 12,
The protection circuit 14, the thermistor 16, the LPFs 17, 18 and the resistor 19 are provided on a printed circuit board.
Is provided in the middle of wiring between the printed circuit board and the battery cell 11.

The protection circuit 14 is for preventing overcharge and overdischarge of the battery cell 11, and the FUSE 15 is for protecting the circuit from overcurrent. Thermistor 1
Numeral 6 is for measuring the temperature at a predetermined position in the battery unit 1, and is arranged, for example, on the way connected to the terminal of the battery cell 11, and outputs the measurement result to the T terminal. ing. The thermistor 16 functions as a temperature measuring unit that measures the temperature of the battery unit 1 at a predetermined position.

The LPFs 17 and 18 are used to prevent malfunction due to noise and to prevent EMI (Electro Magnetic Interferenc).
e: Electromagnetic interference noise and ESD (Electro Static Discharg)
e: electrostatic discharge) is a filter circuit for protecting the EEPROM 13 from the like. The memory element 13 is, for example,
It is composed of a nonvolatile memory such as an EEPROM.
In this embodiment, EE is used as the memory element.
The case where a PROM is used will be described.

The EEPROM 13 is electrically separated from the battery cell 11 so as not to consume the power of the battery cell 11.
3 are configured as independent circuits. That is, in the battery unit 1, in addition to the output terminals (see “+ terminal” and “− terminal” in FIG. 1) of the battery cell 11 for supplying power to the power consuming device as described above,
D for reading / writing information from / to the EEPROM 13
An I / O terminal and a Vcc terminal for supplying drive power to the EEPROM 13 are separately provided. In the present invention, “electrically separated” does not deny that the ground (GND) is shared.

The EEPROM 13 is connected to a Vcc terminal. When the EEPROM 13 is connected to a power consuming device, a charger 2 (described later) and a remaining capacity display device 4 (described later), the power consuming device is connected to the EEPROM 13 via the Vcc terminal. Power is supplied from the battery charger 2 and the remaining capacity display device 4.
The EEPROM 13 and the thermistor 16 are respectively connected to a G terminal for signal ground. The S terminal (sense terminal) is a terminal for measuring the voltage of the battery cell 11 via the resistor 19, and is used to measure the voltage with the + terminal when connected to the charger 2 described later. Is being used. Note that the voltage of the battery cell 11 was measured by using S instead of the-terminal.
The reason for using the terminals is that it is difficult to accurately measure the voltage of the battery cell 11 because the internal resistance of the circuit is large between the + terminal and the − terminal.

Further, the EEPROM 13 includes an LPF 18
Is connected to the DI / O terminal via the
Various data are exchanged with the power consuming device, the charger 2 and the remaining capacity display device 4 via the terminals. The SK terminal is for supplying a clock from the power consuming device, the charger 2 and the remaining capacity display device 4 to the EEPROM 13.

As shown in FIG. 1, the EEPROM 13 has a current value data storage 31 and a voltage data storage 3
2, remaining capacity data storage unit 33, temperature data storage unit 34,
Temperature correction data storage unit 35, deterioration state data storage unit 36
And functions as a deterioration correction data storage unit 37. The current value data storage unit 31 stores the battery cell 11
A plurality of current value data corresponding to various current values flowing through the battery cell 11 are defined, and the voltage data storage unit 32 defines a plurality of voltage data corresponding to various voltages of the battery cell 11, The capacity data storage unit 33 defines corresponding remaining capacity data for each combination of a plurality of current value data and a plurality of voltage data.

The temperature data storage unit 34 defines a plurality of temperature data corresponding to various temperatures at a predetermined position in the battery unit 1 (the mounting position of the thermistor 16). Stores the temperature correction data corresponding to each of the plurality of temperature data. The deterioration state data storage unit 36 stores the battery cell 1
A plurality of deterioration state data corresponding to one of various deterioration states is defined, and the deterioration correction data storage unit 37 stores deterioration correction data corresponding to each of the plurality of deterioration state data.

FIG. 2 is a diagram partially showing an example of the data structure of the EEPROM in the secondary battery unit as one embodiment of the present invention. As shown in FIG.
At predetermined positions in the OM 13, current rate data (current value data), deterioration state data, deterioration correction data, temperature data, temperature correction data, voltage data, and remaining capacity data are stored, respectively.

When the measurement of the current rate is performed in a predetermined range, the current rate data is represented by n representing the range.
A current rate value (unit: 0.01 C) as current value data of a type (n is a natural number; n = 4 in the present embodiment) is defined as a table, and is defined as an actual measured value of the current rate of the battery cell 11. It is set in advance within a possible range. For example, when the measurement of the current rate is performed in the range of 0.2 to 2C, the value of ｛2
A data string of 0, 50, 100, 200 is recorded in advance as a representative value of various values that can be taken as a current rate (current value). Thereby, EEP
The ROM 13 functions as a current value data storage unit 31.

In the example shown in FIG. 2, the current rate data is registered as a 16-bit unsigned integer (hereinafter, such a data format is referred to as "A type"). The deterioration state data is specified by a discharge test result (details will be described later) performed when the battery cell 11 is charged by the charger 2. The deterioration state of the battery cell 11 is determined by devising a method for charging the battery cell 11.
Specifically, during charging, once a predetermined voltage (eg, a fully charged state) is reached, a predetermined time (eg, 1 second)
Discharge is performed, and a voltage value after a predetermined time has elapsed is measured to calculate a voltage drop value.

When the measurement of the IR drop value is performed in a predetermined range, the deterioration state data includes q types (q is a natural number; q = 4 in the present embodiment) of the IR drop value (unit: : MV) is defined as a table. Here, the IR drop indicates a voltage drop due to the internal resistance of the battery cell 11. The voltage drop (internal resistance) increases in accordance with the degree of deterioration of the battery cell 11, and defines q values between the minimum value and the maximum value of the battery voltage after the voltage drop.

For example, in the case of a battery cell 11 having a full charge voltage of 4.1 V (= 4100 mV), $ 3600, 37
A data string of 00, 3800, 3950 is recorded in advance as a representative value of various values that can be taken as a voltage drop value. Thereby, the EEPROM
13 functions as a deterioration state data storage unit 36. In the example shown in FIG. 2, the deterioration state data is registered as the A type.

The deterioration correction data is a ratio (0) of the irreversible battery deterioration capacity corresponding to the IR drop data string (four in this embodiment) of the table defining the deterioration state data.
(.About.100%) is defined as a table. The value stored in the deterioration correction data is a value when there is no correction based on temperature. As the deterioration correction data, for example, a data string such as {10, 50, 75, 100} is recorded, and the deterioration state data string is {3600, 3}.
In the case of 700, 3800, 3950 °, when the IR drop voltage is 3.6 V, it indicates that 10% of the initial capacity is the battery capacity after deterioration.

Similarly, when the IR drop voltage is 3.7 V, 50% of the initial capacity is 3.8 V, and when the IR drop voltage is 3.8 V, 75% of the initial capacity is the battery capacity after deterioration. When the IR drop voltage is 3.95 V, 100% of the initial capacity is the battery capacity after deterioration,
This indicates that the battery cell 11 has not deteriorated. This allows
The EEPROM 13 functions as a deterioration correction data storage unit 37. In the example shown in FIG. 2, the deterioration state data is registered as an 8-bit unsigned integer (hereinafter, such a data format is referred to as “B type”).

An IR drop value is measured when the battery cell 11 is charged by a charger 2 described later, and the measurement result is further stored in a predetermined position (not shown) of the EEPROM 13 by the charger 2. Is recorded. When the battery unit 1 is used by the power consuming device, the power consuming device uses the deterioration correction data stored in the deterioration correction data storage unit 33 based on the IR drop value written by the charger 2. Then, the correction calculation of the remaining capacity of the battery cell 11 is performed.

The temperature data is obtained in a predetermined temperature range.
The temperature of p types (p is a natural number; p = 16 in the present embodiment) representing this range is defined as a table. For example, the operating range of the battery cell 11 is 0 ° C. to 80 ° C.
In the case of, {0,1,2,4,6,8,10,15,
Data strings such as 20, 25, 30, 40, 50, 60, 70, and 80 ° are defined in advance as representative values of various values that can be detected as detected temperatures.

Thus, the EEPROM 13 functions as the temperature data storage unit 34. In addition,
These temperature values defined as temperature data are not limited to integers of 0 or more. In the example shown in FIG. 2, the temperature data is registered as type B.
The temperature correction data defines a reversible battery deterioration capacity ratio (0 to 100%) corresponding to a temperature data string (16 in the present embodiment) of a table defining temperature data. The value stored in the temperature correction data is a value when there is no deterioration due to the use of the battery cell 11.

As the temperature correction data, for example,
$ 5,10,20,40,50,60,70,80,9
0, 95, 100, 95, 90, 80, 60, 40} are recorded, and the temperature data sequence is {0, 1,
2,4,6,8,10,15,20,25,30,4
0, 50, 60, 70, 80 °, the battery cell 1
When the temperature of No. 1 is 0 ° C., it indicates that 5% of the initial capacity is the battery capacity after deterioration due to temperature.

Similarly, when the temperature of the battery cell 11 is 1 ° C., 10% of the initial capacity, and when the temperature of the battery cell 11 is 2 ° C., 20% of the initial capacity,. When the temperature of the battery cell 11 is 10 ° C., 70% of the initial capacity,
... (on the way, omitted) ..., the temperature of the battery cell 11 is 8
At 0 ° C., 40% of the initial capacity is the battery capacity after deterioration due to temperature. Thereby, EEP
The ROM 13 functions as a temperature correction data storage unit 35. In the example shown in FIG. 2, the temperature correction data is registered as a B type.

The voltage data defines m kinds of voltage ranges (m is a natural number; m = 16 in this embodiment) representing the range when the voltage measurement is performed in a predetermined range. Therefore, for example, when the voltage range of the battery cell 11 is 2.7 V to 4.2 V, $ 2700, 280
0,2900,3000,3100,3200,330
0,3400,3500,3600,3700,380
Data strings such as 0, 3900, 4000, 4100, 4200 are defined in advance as representative values of various values that can be taken as voltage values. This allows
The EEPROM 13 functions as the voltage data storage unit 32. In the example shown in FIG.
The voltage data is registered as type A.

The remaining capacity data is a current rate data string (4 in this embodiment) of a table defining current rate data.
) And a voltage data string (16 in this embodiment) of a table defining voltage data,
The percentage of the remaining capacity of the battery cell 11 (0 to 100, respectively)
%). Thereby, the EEPROM
13 functions as a remaining capacity data storage unit 33. FIG. 3 is a diagram showing an example of remaining capacity data.
FIG. 6 shows a relationship between current value data, voltage data, and remaining capacity data as a matrix.

Although the remaining capacity data is not described in the matrix shown in FIG. 3, the remaining capacity is actually stored as a% value (0 to 100) in this matrix. The remaining capacity data is not limited to the% value, but may be stored as, for example, a ratio (0 to 1). These remaining capacities are values in a case where the apparent change in the remaining capacity due to the temperature and the deterioration due to the use of the battery cell 11 are not considered. Secondary batteries such as lithium polymer batteries and lithium ion batteries have the same material composition,
Since the electrical characteristics are different depending on the design specifications such as the electrode structure, the maximum charging capacity, and the generated voltage, the EEPROM 13 is used to accurately calculate the remaining capacity of each battery cell 11.
, It is desirable to store individual values corresponding to the characteristics of the battery cells 11. In the example shown in FIG. 2, the remaining capacity data is registered as a B type.

FIG. 4 is a block diagram showing a configuration of a charger of a secondary battery unit as one embodiment of the present invention.
An example of the circuit configuration is shown in a simplified manner. The charger 2 includes a charge control circuit 21, a constant current discharge circuit 22, an MPU 23, an A / D converter 24, and a power supply circuit 25, as shown in FIG.
And each terminal (“+ terminal”, “− terminal” and “CM” in FIG. 4).
Terminal ").

The charge control circuit 21 applies a predetermined voltage to the battery cells 11 of the battery unit 1. MPU2
Reference numeral 3 denotes an arithmetic element and a storage element such as a ROM and a RAM, and controls the charge control circuit 21. The EEPROM 13 of the battery unit 1 is communicably connected to the MPU 23 via a CM terminal. The CM terminal is a combination of the aforementioned DI / O terminal, S terminal, SK terminal, T terminal, G terminal, and Vcc terminal for convenience.

The A / D converter 24 detects the output voltage of the battery cell 11 and outputs a detection signal to the MPU 23. The A / D converter 24 is connected to the anode output side of the charge control circuit 21. The constant current discharge circuit 22 is for generating a constant current load, and is connected to the output side of the charge control circuit 21 in parallel with the charge control circuit 21. Further, power is supplied from a power supply circuit 25 to each element, circuit, and the like of the charger 2. The constant current discharge circuit 22
May have a plurality of constant current switching mechanisms in order to enable more accurate measurement.

Next, a process in which the charger charges the secondary battery unit as one embodiment of the present invention will be described with reference to FIG.
Will be described according to the flowchart (steps A10 to A90) shown in FIG. When the battery unit 1 is connected to the charger 2 and charging is started, the charger 2 first charges the battery cell 11 until a predetermined voltage (for example, 4.00 V) is reached (step A10). Then, the charger 2 temporarily stores the Ti
After setting mer = 0 (step A20), discharge is started using the constant current discharge circuit 22 or the constant resistance voltage circuit (not shown) (step A30).

Then, this discharge is performed for a predetermined time (for example, 1
Sec) (Step A40), the voltage value of the battery cell 11 is measured (Step A50), and the discharge is stopped (Step A60). The MPU 23 determines I based on the measurement result.
The R drop value is calculated, and the IR drop value is written to a predetermined position (not shown) of the battery unit 1 (step A70).

Thereafter, the charger 2 resumes charging (step A80) and performs charging until the battery cell 11 is fully charged (step A90). FIG. 6 is a block diagram showing a configuration of a remaining capacity display device as one embodiment of the present invention, and is a diagram showing a simplified example of the circuit configuration.
The remaining capacity display device 4 displays the remaining capacity of the battery cells 11 in the battery unit 1 on a remaining capacity display section (display section) 41. As shown in FIG. 6, the D / IO terminal, SK
The battery unit 1 is connected via a terminal, a T terminal, a G terminal, a + terminal, a − terminal and a Vcc terminal.

As shown in FIG. 6, the remaining capacity display device 4 includes a remaining capacity display section (display section) 41 and a microcomputer 42 (hereinafter, referred to as a microcomputer 42).
2 has functions of a remaining capacity data acquisition unit, a calculation unit, and a display control unit), an A / D converter 43, an A / D converter (current value measurement unit) 44, a differential amplifier, and an A / D converter (voltage A measuring unit 45, a voltage regulator 46, and a driving unit 47.

It is to be noted that the remaining capacity display device 4 is often used by being incorporated in the above-described power consuming equipment. Is displayed in various forms on a display (remaining capacity display section 41) or the like of the apparatus. The remaining capacity display unit 41 is communicably connected to the microcomputer 42 and displays information obtained by the microcomputer 42 and the remaining capacity of the battery cell 11. For example, display on a liquid crystal display, lighting of an LED, and the like are performed. Displays the remaining capacity of the battery cell 11.

The voltage regulator 46 is connected to the battery unit 1
The power supplied from the battery cell 11 is converted into a predetermined voltage.
The battery voltage of ４4 V is stabilized at 3.3 V and output. The A / D converter 44 is arranged on the input side of the voltage regulator 46, detects the output voltage of the battery cell 11, outputs a detection signal to the microcomputer 42, and measures the voltage of the battery cell 11. It is designed to function as. The power from the A / D converter 44 is supplied to the EEPROM 13 of the battery unit 1 via the Vcc terminal.

The differential amplifier and the A / D converter 45 are
It is arranged on the input side of the voltage regulator 46, detects the output current of the battery cell 11 from the potential difference between both ends of the resistor 48,
It outputs a detection signal to the microcomputer 42, and functions as a current value measuring unit that measures a current value flowing through the battery cell 11. Note that the resistance value of the resistor 48 for measuring the potential difference is set as small as possible in order to suppress a voltage drop. Therefore, the A / D converter 45 is provided with a differential amplifier for performing signal amplification.

The A / D converter 43 is connected to the battery unit 1
The temperature information (analog signal) measured by the thermistor 16 is converted into a digital signal and output to the microcomputer 42. The microcomputer 42 includes a storage element, an arithmetic element, a clock oscillating unit, and the like (not shown), and controls the entire circuit. Then, the EEPR of the battery unit 1
The OM 13 is communicably connected to the microcomputer 42 via a DI / O terminal.
The remaining capacity data, temperature correction data, and deterioration correction data stored in the remaining capacity data storage unit 31, the temperature correction data storage unit 32, and the deterioration correction data storage unit 33 are transmitted to the microcomputer 42. It has become.

The microcomputer 42 stores the current value (current value) measured by the A / D converter (current value measuring unit) 45 in the current value data storage 31 of the EEPROM 13 in the battery unit 1 based on the actually measured value of the current rate (current value). A current rate (current value data) corresponding to an actual measured value of the current value is selected from a plurality of current value data defined in advance.

Further, the microcomputer 42 reads the EEPROM 13 in the battery unit 1 based on the measured value of the voltage measured by the A / D converter (voltage measuring unit) 44.
The voltage data corresponding to the actually measured voltage value is selected from among a plurality of voltage data defined in advance in the voltage data storage unit 32. Furthermore, microcomputer 4
2 denotes an EEPROM 1 in the battery unit 1 based on a measurement result of the thermistor 16 in the battery unit 1.
The temperature data corresponding to the actually measured value is selected from a plurality of temperature data defined in advance in the third temperature data storage unit 34.

Further, the microcomputer 42 determines the EEPROM of the battery unit 1 based on the IR drop value stored in the EEPROM 13 of the battery unit 1.
The deterioration state data corresponding to the IR drop value is selected from a plurality of deterioration state data defined in the deterioration state data storage unit 36 of the OM 13 in advance.

As a method for the microcomputer 42 to select the current value data, the voltage data, the temperature data, and the deterioration state data, for example, the microcomputer 42 may select and obtain each value closest to the actually measured value. In addition, the current value data, the voltage data, the temperature data, and the deterioration state data are associated with each other in advance as representative values of each value in a predetermined range, and these representative values (current value Data, voltage data, temperature data, and deterioration state data) may be selected, and various modifications may be made without departing from the spirit of the present invention.

The microcomputer 42 calculates the voltage based on the voltage data obtained from the voltage measured by the A / D converter 44 and the current rate data obtained from the current rate measured by the A / D converter 45. The remaining capacity data corresponding to the combination of the value and the current rate is transmitted to the EEPR of the battery unit 1 via the DI / O terminal.
The data is obtained from the OM 13 (remaining capacity data storage unit 35), and functions as a remaining capacity data obtaining unit.

Further, the microcomputer 42 calculates the remaining capacity of the battery cell 11 based on the obtained remaining capacity data, and also functions as a calculation unit. Further, the microcomputer 42 calculates the calculated battery cell 11
It also functions as a display control unit for displaying the remaining capacity on the remaining amount display unit (display unit) 41. The microcomputer 42 outputs a clock for driving the EEPROM 13 of the battery unit 1 to the SK terminal.

The driving section 47 is for realizing various functions other than the display of the remaining capacity. For example, when the remaining capacity display device 4 is incorporated in a portable telephone, it serves as a telephone. A circuit or the like for realizing the above function corresponds to the driving unit 47. A method of displaying the remaining capacity of the battery cell in the secondary battery unit as one embodiment of the present invention using the remaining capacity display device 4 configured as described above is shown in the flowchart of FIG.
0 to B130).

When the battery unit 1 is connected to the remaining capacity display device 4, the microcomputer 42 measures the voltage of the battery cell 11 by the A / D converter 44 (step B1).
0). Then, the microcomputer 42 acquires voltage data (for example, 3700 mV) based on the actually measured value (for example, 3680 mV) of the voltage with reference to the voltage data storage unit 32 of the EEPROM 13 in the battery unit 1 (step B20).

The microcomputer 42 measures the current rate of the battery cell 11 using the A / D converter 45 (step B30). Then, the microcomputer 42 stores the current value data storage unit 3 of the EEPROM 13 in the battery unit 1.
1 with reference to the actual value of this current rate (for example, 45 C
/ 100) based on the current rate data (for example, 50C
/ 100) (step B40).

The microcomputer 42 refers to the remaining capacity data storage section 33 of the EEPROM 13 in the battery unit 1 and selects the voltage data (3700 mV) selected as described above.
And remaining capacity data (70%) corresponding to the combination of the current rate data and the current rate data (50C / 100) (step B50). Further, the microcomputer 42 acquires the temperature at a predetermined position of the battery cell 11 from the thermistor 16 of the battery unit 1 (step B60), and the EE in the battery unit 1
With reference to the temperature data storage unit 34 of the PROM 13, temperature data (for example, 10 ° C.) is obtained based on the actually measured value of the temperature of the battery cell 11 (for example, 12 ° C.) (Step B).
70).

The microcomputer 42 controls the battery unit 1
Temperature correction data storage section 35 of EEPROM 13
, Temperature correction data (for example, 70%, that is, 0.7) is acquired (step B80). Further, the microcomputer 42 acquires the IR drop value recorded in the EEPROM 13 by the charger 2 (step B90), and refers to the deterioration state data storage section 36 of the EEPROM 13 in the battery unit 1 to refer to the IR drop value of the battery cell 11. The deterioration state data (for example, 3800 m
V) is obtained (step B100).

The microcomputer 42 controls the battery unit 1
Correction data storage unit 37 of the EEPROM 13
, Deterioration correction data (for example, 75%, that is, 0.75) is acquired (step B110). The microcomputer 42 uses the temperature correction data (0.7) obtained in step B80 and the deterioration correction data (0.75) obtained in step B110 for the remaining capacity data (70%) obtained in step B50. Then, correction (for example, 70% × 0.7 × 0.75 ≒ 40%) is performed (step B120), and the microcomputer 42 displays the remaining capacity data thus calculated on the remaining capacity display unit 41 (step B120). B130).

As described above, according to the secondary battery unit and the remaining capacity display device as one embodiment of the present invention, the EEPROM 13 in the battery unit 1 includes the current value data storage unit 31 and the voltage data storage unit 32. Therefore, instead of directly using the current values and voltages measured by the A / D converters 45 and 44, current rate data and voltage preset in the current value data storage 31 and voltage data storage 32 are used. The remaining capacity can be acquired based on the data, and the remaining capacity of the battery cell 11 can be quickly acquired.

Further, the provision of the remaining capacity data storage section 33 allows the remaining capacity data to be obtained based on the current rate data and the voltage data, thereby speeding up the display of the remaining capacity of the battery cell. Also, when acquiring the remaining capacity,
Since there is no need to perform calculations, the device configuration can be simplified and the manufacturing cost can be reduced. In particular, since the remaining capacity data is recorded as a table in the EEPROM 13, it is possible to use a small-capacity and inexpensive memory element such as an EEPROM as the memory element.

Even when the relationship between the current rate and the voltage is non-linear, the remaining capacity of the battery cell 11 can be accurately calculated by using the remaining capacity data corresponding to the combination of the current rate data and the voltage data. can do. In the present invention, the remaining capacity is obtained based on the relation table between the current rate and the voltage, which is considered to have the largest effect on the measured value, so that the remaining capacity of the battery cell 11 is easily increased. It can be measured with accuracy.

Further, in the present invention, it can be said that the remaining capacity data is corrected in advance by the current rate which is considered to be the largest factor of the error, and that the accuracy of the remaining capacity is high. be able to. Therefore, it is not always necessary to perform the correction based on the temperature or the deterioration state, and it is possible to entrust the user of the battery unit 1 (the remaining capacity display device 4) to determine whether to perform the correction based on the temperature or the deterioration state. It is possible to improve the degree of freedom of the user.

That is, in the above embodiment,
The remaining capacity data acquired from the remaining capacity data storage unit 33 is corrected based on the temperature and the deterioration state. However, the correction is not limited thereto. For example, only the correction based on the temperature or the correction based on the deterioration state is performed. Or
Without performing these corrections, the remaining capacity data storage 33
May be used directly.

Further, since a memory element (EEPROM or the like) for storing current value data, voltage data, remaining capacity data, etc. is inexpensive, a conventional secondary battery unit according to an embodiment of the present invention is not used. The manufacturing cost does not increase significantly as compared with the secondary battery unit. Further, in general, the correlation between the battery voltage and the remaining capacity changes depending on the current rate flowing at that time. In the present invention, the remaining capacity data is not only the battery voltage but also a plurality of current rate data. Therefore, the remaining capacity of the battery cell 11 can be measured more accurately.

Further, since the EEPROM 13 stores the temperature correction data defining a plurality of temperature correction data corresponding to various temperatures at predetermined positions of the battery unit 1, the remaining battery cells 11 which are affected by the temperature are stored. The capacity can be obtained, and the accuracy of the remaining capacity can be improved. Further, since the temperature data storage unit 34 and the temperature correction data storage unit 35 are provided, there is no need to perform arithmetic processing using the measured temperature directly, and the remaining capacity is corrected based on preset temperature data. In addition, a highly accurate remaining capacity can be quickly obtained, the load on the remaining capacity display device 4 can be reduced, and the device configuration can be simplified.

The EEPROM 13 stores the battery cells 11
Since a plurality of deterioration correction data corresponding to the various deterioration states are stored, by performing correction using the deterioration correction data, the remaining capacity of the battery cell 11 in consideration of the influence of the deterioration of the battery cell 11 is stored. The accuracy of the remaining capacity can be improved. Furthermore, since it has the deterioration state data storage unit 36 and the deterioration correction data storage unit 37, it is not necessary to perform an arithmetic process by directly using the measured deterioration state (voltage drop value). Since the remaining capacity is corrected based on the remaining capacity, it is possible to quickly obtain a high-precision remaining capacity, reduce the load on the remaining capacity display device, and simplify the device configuration. Can correct the remaining capacity of the battery unit 1 such as a remaining capacity display device or a power consuming device by a microprocessor on which the battery unit 1 is mounted, so that the structure of the battery unit 1 can be simplified. Can be

The present invention is not limited to the above-described embodiment, but can be implemented in various modifications without departing from the spirit of the present invention. For example, in the above-described embodiment, when the voltage measured by the A / D converter 44 or the current rate measured by the A / D converter 45 does not match the voltage data or the current rate data stored in the EEPROM 13 in advance. The remaining capacity data corresponding to the combination of the voltage data and the current rate data is forcibly approximated to these pre-registered voltage data and current rate data, but is not limited to this. is not.

For example, if the measured current rate is E
If the voltage data and the current rate data stored in the EPROM 13 do not match, linear correction may be performed on the remaining capacity data. For example, if the voltage data is $ 27
00, ..., 3600, 3700, ..., 420
If the measured value of the voltage is 3650 mV when defined as a data string of 0 °, 3600 mV
The intermediate value between the remaining capacity data at 3700 mV and the remaining capacity data at 3700 mV may be used as the remaining capacity data corresponding to this measured value.

That is, when the voltage measurement result by the A / D converter (voltage measurement unit) 44 is not stored in the EEPROM 13 (voltage data storage unit 32),
When the measurement result of the current rate (current value) by the D converter (current value measurement unit) 45 is not stored in the EEPROM 13 (current value data storage unit 31), the microcomputer (remaining capacity data acquisition unit) 42 The remaining capacity data corresponding to the measurement result may be obtained by performing linear correction using the registered voltage data, current value data, and remaining capacity data corresponding to these.

As described above, the method for detecting the state of deterioration of the battery cell 11 is as follows.
However, the present invention is not limited to the method using the IR drop value defined by the above voltage. For example, the deterioration state of the battery cell 11 may be detected based on a difference in discharge time when the battery cell is discharged to a constant voltage. Further, in the battery unit 1 of the present invention in each of the above-described embodiments, the writing of the IR drop value to the EEPROM 13 and the calculation of the remaining capacity are not limited to the charger and the power consuming device, and the battery unit 1 can be connected. Any device may be used as long as it is a suitable device.

In the above-described embodiment, the current value data storage unit 3 is stored in the EEPROM 13 of the battery unit 1.
1, voltage data storage unit 32, remaining capacity data storage unit 33,
Temperature data storage unit 34, temperature correction data storage unit 35, deterioration state data storage unit 36, and deterioration correction data storage unit 3
7 is provided, but the present invention is not limited to this, and all or at least a part thereof may be provided on the remaining capacity display device 4 side.

Further, in the above-described embodiment, the current value measuring section (A / D converter 4
5) and a voltage measuring unit (A / D converter 44), but are not limited thereto.
These may be configured to be included in the battery unit 1. In addition, if each embodiment of this invention is disclosed, it can be manufactured by those skilled in the art.

[0075]

As described above, according to the secondary battery unit and the remaining capacity display device of the present invention, the following effects and advantages are obtained. (1) A memory element in the secondary battery unit stores a current value data storage unit that defines a plurality of current value data corresponding to various current values flowing through the battery cell, and a plurality of voltages corresponding to various voltages of the battery cell. Since it has a voltage data storage unit that defines data, instead of directly using the measured current value and voltage, the remaining capacity can be obtained based on preset current value data and voltage data. Can be quickly obtained (claims 1, 8, 9, 10).

(2) Since each combination of a plurality of current value data and a plurality of voltage data has a remaining capacity data storage unit for defining corresponding remaining capacity data,
The remaining capacity data can be obtained based on the current value data and the voltage data, and the display of the remaining capacity of the battery cell can be speeded up. Furthermore, since there is no need to perform calculations when acquiring the remaining capacity, the configuration of the apparatus can be simplified and the manufacturing cost can be reduced (claims 1, 8, 9, and 10). .

(3) Since the memory element has a temperature correction data storage section for storing a plurality of temperature correction data corresponding to various temperatures at predetermined positions of the secondary battery unit,
The remaining capacity of the battery cell can be obtained in consideration of the influence of the temperature, and the accuracy of the remaining capacity can be improved (claims 2 and 9). (4) A temperature data storage unit that defines a plurality of temperature data corresponding to various temperatures at a predetermined position of the battery cell, and a temperature correction data storage unit that stores temperature correction data corresponding to each of the plurality of temperature data. Therefore, it is not necessary to perform arithmetic processing using the measured temperature directly, and the remaining capacity is corrected based on the preset temperature data, so that a highly accurate remaining capacity can be quickly obtained, and ,
The load on the remaining capacity display device can be reduced, and the device configuration can be simplified (claims 3 and 9).

(5) Since there is provided a deterioration correction data storage unit for storing a plurality of deterioration correction data corresponding to various deterioration states of the battery cell, it is necessary to obtain the remaining capacity of the battery cell in consideration of the influence of the deterioration of the battery cell. And the accuracy of the remaining capacity can be improved (claims 4, 10, 11, and 12). (6) A deterioration state data storage unit that defines a plurality of deterioration state data corresponding to various deterioration states of the battery cell, and a deterioration correction data storage unit that stores deterioration correction data corresponding to each of the plurality of deterioration state data. Therefore, there is no need to perform an arithmetic process by directly using the measured deterioration state (voltage drop value), and the remaining capacity is corrected based on the preset deterioration state data. In addition, the load on the remaining capacity display device can be reduced, and the device configuration can be simplified (claims 4, 6, 10, 11, and 1).
2, Claim 13).

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a secondary battery unit as one embodiment of the present invention.

FIG. 2 is a diagram partially showing an example of a data configuration of an EEPROM in a secondary battery unit as one embodiment of the present invention.

FIG. 3 is a diagram illustrating an example of remaining capacity data.

FIG. 4 is a block diagram showing a configuration of a charger of the secondary battery unit 1 as one embodiment of the present invention.

FIG. 5 is a flowchart illustrating a process in which a charger charges a secondary battery unit as one embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of a remaining capacity display device as one embodiment of the present invention.

FIG. 7 is a flowchart illustrating a method of displaying the remaining capacity of a battery cell in a secondary battery unit as one embodiment of the present invention by a remaining capacity display device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Secondary battery unit 2 Charger 4 Remaining capacity display device 11 Battery cell 12 Circuit part 13 EEPROM (memory element) 14 Protection circuit 15 FUSE 16 Thermistor (temperature measuring part) 17, 18 LPF 19 Resistance 21 Charge control circuit 22 Constant current Discharge circuit 23 MPU 24 A / D converter 25 Power supply circuit 31 Current value data storage unit 32 Voltage data storage unit 33 Remaining capacity data storage unit 34 Temperature data storage unit 35 Temperature correction data storage unit 36 Deterioration state data storage unit 37 Degradation correction Data storage unit 41 Remaining amount display unit 42 Microcomputer (remaining capacity data acquisition unit, calculation unit, display control unit) 43 A / D converter 44 A / D converter (voltage measurement unit) 45 A / D converter (current value measurement unit) 46 Voltage regulator 47 Driver 48 Resistance

Continued on the front page F term (reference) 2G016 CA04 CB12 CB21 CB31 CC01 CC04 CC05 CC06 CC07 CC13 CC16 CC23 CC27 CC28 CD18 CF06 5G003 BA01 DA04 EA05 GC05 5H030 AA04 AA06 AA10 AS11 FF22 FF41 FF42 FF44 FF51

Claims (14)

[Claims] 1. A secondary battery unit comprising a chargeable battery cell and a memory element, wherein the memory element stores a plurality of current value data corresponding to various current values flowing through the battery cell. A current value data storage unit to define, a voltage data storage unit to define a plurality of voltage data corresponding to various voltages of the battery cell, and for each combination of the plurality of current value data and the plurality of voltage data, And a remaining capacity data storage unit for defining corresponding remaining capacity data. 2. The memory device according to claim 1, wherein said memory element has a temperature correction data storage unit for storing a plurality of temperature correction data corresponding to various temperatures at predetermined positions of said secondary battery unit. Secondary battery unit. 3. The memory device further comprises: a temperature data storage unit for defining a plurality of temperature data corresponding to various temperatures at a predetermined position of the secondary battery unit; The secondary battery unit according to claim 2, wherein the temperature correction data corresponding to each of the temperature data is stored. 4. The memory device according to claim 1, wherein the memory element includes a deterioration correction data storage unit that stores a plurality of deterioration correction data corresponding to various deterioration states of the battery cell.
The secondary battery unit according to claim 3. 5. The memory device further includes a deterioration state data storage unit that defines a plurality of deterioration state data corresponding to various deterioration states of the battery cell, wherein the deterioration correction data storage unit includes the plurality of deterioration states. 5. The secondary battery unit according to claim 4, wherein the deterioration correction data corresponding to each data is stored. 6. The secondary battery unit according to claim 4, wherein the deterioration state of the battery cell is represented by a voltage drop value in a discharge test of the battery cell. 7. The secondary battery unit according to claim 1, wherein the battery cell is a lithium secondary battery. 8. A remaining capacity display device for displaying the remaining capacity of the battery cell in the secondary battery unit according to any one of claims 1 to 7 on a display unit, wherein the remaining battery cell flows to the battery cell. A current value measuring unit for measuring a current value, a voltage measuring unit for measuring the voltage of the battery cell, a voltage measured by the voltage measuring unit, and a current value measured by the current value measuring unit. A remaining capacity data acquisition unit for acquiring the corresponding remaining capacity data from the remaining capacity data storage unit; and an operation for calculating the remaining capacity of the battery cell based on the remaining capacity data acquired by the remaining capacity data acquisition unit And a display control unit for displaying the remaining capacity of the battery cell calculated by the arithmetic unit on the display unit. 9. A remaining capacity display device for displaying the remaining capacity of the battery cell in the secondary battery unit according to claim 2 on a display unit, wherein a current value flowing through the battery cell is measured. A current value measurement unit, a voltage measurement unit that measures the voltage of the battery cell, a voltage measured by the voltage measurement unit, and the remaining capacity data based on a current value measured by the current value measurement unit. A remaining capacity data acquisition unit that acquires the corresponding remaining capacity data from a storage unit; an operation unit that computes the remaining capacity of the battery cell based on the remaining capacity data acquired by the remaining capacity data acquisition unit; A display control unit for displaying the remaining capacity of the battery cell calculated by the unit on the display unit, wherein the calculation unit uses the temperature correction data stored in the temperature correction data storage unit to display the battery cell. Calculate the remaining capacity of A remaining capacity display device, characterized in that: 10. A remaining capacity display device for displaying a remaining capacity of a battery cell in a secondary battery unit according to claim 4 or 5 on a display unit, wherein a current for measuring a current value flowing through the battery cell is provided. A value measurement unit; a voltage measurement unit that measures the voltage of the battery cell; a voltage measurement unit that stores the remaining capacity data based on the voltage measured by the voltage measurement unit and a current value measured by the current value measurement unit. A remaining capacity data acquisition unit that acquires the corresponding remaining capacity data from the unit; a computing unit that computes the remaining capacity of the battery cell based on the remaining capacity data acquired by the remaining capacity data acquisition unit; A display control unit for displaying the remaining capacity of the battery cell calculated by the display unit on the display unit, wherein the calculation unit uses the deterioration correction data stored in the deterioration correction data storage unit to display the remaining capacity of the battery cell. Calculate remaining capacity A remaining capacity display device, characterized in that: 11. The memory element of the secondary battery unit includes a deterioration correction data storage unit that stores a plurality of deterioration correction data corresponding to various deterioration states of the battery cell, and the arithmetic unit performs the deterioration correction. The remaining capacity display device according to claim 9, wherein the remaining capacity of the battery cell is calculated using the deterioration correction data stored in the data storage unit. 12. The memory element of the secondary battery unit includes a deterioration state data storage unit that defines a plurality of deterioration state data corresponding to various deterioration states of the battery cell, and the deterioration correction data storage unit The remaining capacity display device according to claim 11, wherein deterioration correction data corresponding to each of the plurality of deterioration state data is stored. 13. The remaining capacity display according to claim 10, wherein the state of deterioration of the battery cell is represented by a voltage drop value in a discharge test of the battery cell. apparatus. 14. The remaining capacity display device according to claim 8, wherein the battery cell is a lithium secondary battery.